Deposition device

TECHNICAL FIELD

0001The present invention relates to a deposition device that forms a thin film on a workpiece, such as a semiconductor wafer, using a source gas.

BACKGROUND ART

0002Recently, due to a miniaturization of a semiconductor integrated circuit apparatus, a diameter of copper (Cu) via plug formed in an interlayer insulation film has been reduced from 65 nm to 45 nm. Further, it is expected that a diameter of a via plug will be further reduced to 32 nm or 22 nm in near future.

0003As the miniaturization is progressed in the semiconductor integrated circuit apparatus, the conventional CVD method has a difficulty in depositing a barrier metal film or Cu seed layer on a fine via hole or wiring groove in terms of a step coverage. Therefore, a deposition technique using MOCVD method or ALD method through which an excellent step coverage can be achieved draws attention. Since the interlayer insulation film (low-k film) consisting of low dielectric materials widely used recently tends to be damaged by heat, it is considered that a film deposition by MOCVD method or ALD method is carried out at a low temperature at which low-k film is not damaged.

0004In the meantime, since a metal compound in which metal atoms are bonded with an organic group is generally used as a raw material in the MOCVD method or ALD method, impurities are likely to remain in a formed film. Therefore, even though the formed film seems to have an excellent step coverage at first glance, the quality of the film is unstable. For example, in a case where the Cu-plated seed layer is formed on Ta barrier metal film by the MOCVD method, an aggregation can be easily generated in the seed layer so that it is difficult to stably deposit a seed layer that covers the Ta barrier metal film with a uniform film thickness. When an electroplating is performed for the Cu layer using the seed layer that generated the aggregation as an electrode, potential defects are included in the Cu layer which fills the wiring groove or via hole to cause problems, such as for example, an increase in electrical resistance as well as a degradation of either electro-migration resistance or stress migration tolerance.

0005Accordingly, there has been proposed a method in which a barrier metal film or seed layer is directly formed on the interlayer insulation layer by MOCVD method using metal carbonyl raw material (e.g., Patent Documents 1 and 2). The metal carbonyl raw material can be easily pyrolyzed at a relatively low temperature to form a metal film and CO gas serving as ligand of the metal carbonyl raw material is exhausted outside a deposition reaction system without remaining in the formed film, so that a high-quality barrier metal film or seed layer having very few impurities can be formed. With the above-described method, it is possible to form W film using, for example, W(CO)₆, as the barrier metal film, or Ru film using, for example, Ru₃(CO)₁₂, as the seed layer.

0006In this case, since the metal carbonyl raw material has a characteristic that decomposes very easily at a relatively low temperature, CO gas having a decomposition suppressing function is utilized as a carrier gas. A source gas consisting of the metal carbonyl raw material is supplied from a shower head installed at a ceiling part of a processing container to be deposited by, for example, CVD method, on a semiconductor wafer mounted on a mounting platform to be heated.

0007However, when depositing a film by supplying the metal carbonyl source gas using the shower head, a film thickness of the central portion of the semiconductor wafer which is the workpiece increases and the film thickness gradually decreases as it goes to the periphery of the semiconductor wafer.

0008Therefore, as a deposition device capable of avoiding the problems described above, a deposition device has been proposed in which a baffle plate is installed at a ceiling part of a processing container instead of a shower head, an annular internal partition wall is installed to surround a processing space within a processing container, and the source gas is supplied toward the area further outside than the outer peripheral end of the semiconductor wafer mounted on a mounting platform from a gas discharge port installed at the peripheral edges of the baffle part (Patent Document 3). In the deposition device, most of the source gas supplied to the processing space downwardly from the gas discharge port installed at the peripheral edges of the baffle part flows downwardly and a portion of the source gas is diffused to flow toward a central portion of the processing space, so that a thin film is formed on a surface of the semiconductor wafer which is the workpiece. In the meantime, a gas contained in the processing space is exhausted toward downward from an annular gas outlet formed between a lower end of an inner partition wall and the mounting platform.

CITATION LIST

0009Patent Document <ul id="ul0001" list-style="none"><li id="ul0001-0001" num="0010">[Patent Document 1] Japanese Patent Application Laid-Open No. 2002-60944</li><li id="ul0001-0002" num="0011">[Patent Document 2] Japanese Patent Application Laid-Open No. 2004-346401</li><li id="ul0001-0003" num="0012">[Patent Document 3] Japanese Patent Application Laid-Open No. 2009-239104</li></ul>

SUMMARY OF INVENTION

0013Since supplying a source gas to a central portion of the semiconductor wafer which is the workpiece is suppressed by installing the baffle plate described above, the increase of the film thickness of the central portion of the semiconductor wafer is avoided, so that a high in-plane uniformity of the film thickness can be maintained. However, since most of the gas discharged from the gas discharge port of the peripheral edge of the baffle plate is exhausted from the gas outlet and thus an amount of the source gas contributing to the film deposition becomes small, it is not possible to achieve a sufficiently high deposition rate.

0014The organometallic compound, such as Ru₃(CO)₁₂, is an expensive raw material and is thus required to be recovered and reused. However, in the apparatus as described in Patent Document 3, since the mounting platform is set to a high temperature, the source gas is decomposed at the peripheral edge of the mounting platform to cause an unnecessary film to be deposited thereon, making it difficult to recover the raw material.

0015Therefore, an object of the present invention is to provide a deposition device capable of achieving a good in-plane uniformity of the film thickness as well as a high deposition rate. In addition, the present invention intends to provide a deposition device capable of effectively recovering the raw material.

0016A first aspect of the present invention provides a deposition device for forming a thin film on a surface of a workpiece using a source gas consisting of an organometallic compound, the deposition device including: a processing container which is vacuum-exhaustible in which the workpiece is accommodated; a mounting platform accommodated in the processing container configured to mount a workpiece W and installed with a heater for heating the workpiece; a gas introduction mechanism disposed above the mounting platform to be opposed thereto and configured to introduce the source gas toward the area further outside than the outer peripheral end of the workpiece on the mounting platform; an internal partition wall which surrounds a processing space S above the mounting platform to form a boundary for the processing space and installed such that the lower end portion of the internal partition wall comes close to the mounting platform to form a gas outlet between the lower end portion of the internal partition wall and the peripheral edges of the mounting platform; and an orifice forming member installed on the lower end of the internal partition wall to extend radially inward toward the mounting platform to form an orifice communicating with the gas outlet between the internal partition wall and the peripheral edge of the mounting platform.

0017A second aspect of the present invention provides a deposition device for forming a thin film on a surface of a workpiece using a source gas consisting of an organometallic compound, the deposition device including: a processing container which is vacuum-exhaustible in which the workpiece is accommodated; a mounting platform accommodated in the processing container configured to mount a workpiece W and installed with a heater for heating the workpiece; a gas introduction mechanism disposed above the mounting platform to be opposed thereto and configured to introduce the source gas toward the area further outside than the outer peripheral end of the workpiece on the mounting platform; an internal partition wall which surrounds a processing space S above the mounting platform to form a boundary for the processing space and installed such that the lower end portion of the internal partition wall comes close to the mounting platform to form a gas outlet between the lower end portion of the internal partition wall and the peripheral edges of the mounting platform; and an orifice forming member intervened to form an upper gap and a lower gap in the gas outlet, the inner peripheral end is disposed to extend radially inward toward the mounting platform, and the upper gap forms an orifice.

0018A third aspect of the present invention provides a deposition device for forming a thin film on a surface of a workpiece using a source gas consisting of an organometallic compound, the deposition device including: a processing container which is vacuum-exhaustible in which the workpiece is accommodated; a mounting platform accommodated in the processing container configured to mount a workpiece W and installed with a heater for heating the workpiece; a gas introduction mechanism disposed above the mounting platform to be opposed thereto and configured to introduce the source gas toward the area further outside than the outer peripheral end of the workpiece on the mounting platform; an internal partition wall which surrounds a processing space S above the mounting platform to form a boundary for the processing space and installed such that the lower end portion of the internal partition wall comes close to the mounting platform to form a gas outlet between the lower end portion of the internal partition wall and the peripheral edges of the mounting platform; an orifice forming member intervened to form an upper gap and a lower gap in the gas outlet, the inner peripheral end is disposed to extend radially inward toward the mounting platform, and the upper gap being form an orifice; a purge gas supply mechanism configured to supply a purge gas to the lower gap; and a cover member installed to cover the outer part of the peripheral edge of the mounting platform, and the internal partition wall, the orifice forming member and the cover member are maintained at a temperature lower than the decomposition temperature of the source gas and equal to or higher than a solidification temperature or a liquefaction temperature, and the peripheral edge of the mounting platform is maintained at a temperature at which the source gas is decomposed.

0019A fourth aspect of the present invention provides a deposition device for forming a thin film on a surface of a workpiece using a source gas consisting of an organometallic compound, the deposition device including: a processing container which is vacuum-exhaustible in which the workpiece is accommodated; a mounting platform accommodated in the processing container configured to mount a workpiece W and installed with a heater for heating the workpiece; a gas introduction mechanism disposed above the mounting platform to be opposed thereto and configured to introduce the source gas toward the area further outside than the outer peripheral end of the workpiece on the mounting platform; an internal partition wall which surrounds a processing space S above the mounting platform to form a boundary for the processing space and installed such that the lower end portion of the internal partition wall comes close to the mounting platform to form a gas outlet between the lower end portion of the internal partition wall and the peripheral edges of the mounting platform; and a orifice forming member installed on the lower end of the internal partition wall to extend radially inward toward the mounting platform to form an orifice communicating with the gas outlet between the internal partition wall and the peripheral edge of the mounting platform, and maintained at a temperature lower than the decomposition temperature of the source gas and higher than the solidification temperature or liquefaction temperature thereof, and the mounting platform includes a mounting platform main body having the heater for heating the workpiece, a peripheral ring member installed to be apart from the workpiece in the periphery of the mounting platform main body and of which temperature is adjusted by being partially contacted with the mounting platform main body, and a cover ring member installed to be apart from the workpiece in the periphery of the mounting platform body, and installed on the peripheral ring member.

BRIEF DESCRIPTION OF DRAWINGS

0020<figref idref="DRAWINGS">FIG. 1</figref> is a schematic configuration view illustrating a deposition device, according to a first embodiment of the present invention.

0021<figref idref="DRAWINGS">FIG. 2</figref> is a plan view illustrating an example of a baffle plate used in the deposition device of <figref idref="DRAWINGS">FIG. 1</figref>.

0022<figref idref="DRAWINGS">FIG. 3</figref> is an enlarged cross-sectional view illustrating a mounting platform used in the deposition device of <figref idref="DRAWINGS">FIG. 1</figref>.

0023<figref idref="DRAWINGS">FIG. 4</figref> is a partially enlarged cross-sectional view illustrating a portion of the mounting platform used in the deposition device of <figref idref="DRAWINGS">FIG. 1</figref>.

0024<figref idref="DRAWINGS">FIG. 5</figref> is a view illustrating a state where the mounting platform is lowered down in the deposition device of <figref idref="DRAWINGS">FIG. 1</figref>.

0025<figref idref="DRAWINGS">FIG. 6A</figref> is a diagram illustrating flow of a source gas within a processing container of the deposition device, according to the first embodiment of the present invention.

0026<figref idref="DRAWINGS">FIG. 6B</figref> is an enlarged diagram illustrating the surrounding regions of an orifice illustrated in <figref idref="DRAWINGS">FIG. 6A</figref> and a flow of a source gas flowing in the surrounding regions.

0027<figref idref="DRAWINGS">FIG. 7</figref> is a diagram illustrating a flow of a source gas within a processing container in the deposition device, according to the related art.

0028<figref idref="DRAWINGS">FIG. 8</figref> is a partially enlarged cross-sectional view illustrating a portion of a mounting platform in a deposition device, according to a second embodiment of the present invention.

0029<figref idref="DRAWINGS">FIG. 9</figref> is a side view illustrating the portion of the mounting platform in the deposition device, according to the second embodiment of the present invention.

0030<figref idref="DRAWINGS">FIG. 10</figref> is a diagram illustrating a flow of a source gas within the processing container of the deposition device, according to the second embodiment of the present invention.

0031<figref idref="DRAWINGS">FIG. 11</figref> is a graph illustrating a relationship between the deposition rates and the in-plane uniformities in the deposition devices, according to the first and second embodiments of the present invention and the related art.

0032<figref idref="DRAWINGS">FIG. 12</figref> is a partially enlarged cross-sectional view illustrating a portion of a mounting platform in a deposition device, according to a third embodiment of the present invention.

0033<figref idref="DRAWINGS">FIG. 13</figref> is a diagram illustrating temperatures of a semiconductor wafer W and each constituents, and flow of the source gas within the processing container of the deposition device, according to the third embodiment of the present invention.

0034<figref idref="DRAWINGS">FIG. 14</figref> is a graph illustrating a relationship between the deposition rate and in-plane uniformity in the deposition devices, according to the first and second embodiments of the present invention and the related art.

0035<figref idref="DRAWINGS">FIG. 15</figref> is a graph illustrating a relationship between a temperature of a shield ring and in-plane uniformity of film thickness.

0036<figref idref="DRAWINGS">FIG. 16</figref> is a graph illustrating a relationship between flow rate of the purge gas, film thickness and in-plane uniformity of film thickness in the deposition device, according to the third embodiment of the present invention.

0037<figref idref="DRAWINGS">FIG. 17</figref> is a graph illustrating a relationship between a recovery rate of raw material and in-plane uniformity of film thickness in a case where the temperature of the cover ring varies.

0038<figref idref="DRAWINGS">FIG. 18</figref> is a graph illustrating results of adhesion of the source gas confirmed with respect to the deposition device of the Paten Document 3 and the deposition device, according to the third embodiment and two intermediate level deposition devices of the deposition devices.

0039<figref idref="DRAWINGS">FIG. 19</figref> is a partially enlarged cross-sectional view illustrating a portion of the mounting platform in a deposition device, according to a fourth embodiment of the present invention.

DETAILED DESCRIPTION

0040Hereinafter, an exemplary embodiment of a deposition device of the present invention will be described in detail with reference to the accompanying drawings.

Deposition Device According to First Embodiment

0041<figref idref="DRAWINGS">FIG. 1</figref> is a schematic configuration view illustrating a deposition device according to a first embodiment of the present invention. <figref idref="DRAWINGS">FIG. 2</figref> is a plan view illustrating an example of a baffle plate used in the deposition device of <figref idref="DRAWINGS">FIG. 1</figref>. <figref idref="DRAWINGS">FIG. 3</figref> is an enlarged cross-sectional view illustrating a mounting platform used in the deposition device of <figref idref="DRAWINGS">FIG. 1</figref>. <figref idref="DRAWINGS">FIG. 4</figref> is a partially enlarged cross-sectional view illustrating a portion of the mounting platform used in the deposition device of <figref idref="DRAWINGS">FIG. 1</figref>. <figref idref="DRAWINGS">FIG. 5</figref> is a view illustrating a state where the mounting platform is lowered down. Herein, a case will be exemplified where a film formed with Ru metal film is deposited using Ru₃(CO)₁₂, which is organometallic compound carbonyl system, as a raw material of organometallic compound and using carbon monoxide (CO) as a carrier gas.

0042As illustrated in <figref idref="DRAWINGS">FIG. 1</figref>, a deposition device <b>20</b> according to the first embodiment includes a columnar container-shaped processing container <b>22</b> made of, for example, an aluminium alloy. Processing container <b>22</b> is constituted with an upper chamber having a larger diameter and a lower chamber having a smaller diameter, and an inner space of the lower chamber serves as an exhaust space <b>24</b>. An exhaust port <b>26</b> is formed at a lower side wall partitioning exhaust space <b>24</b> serving as the lower chamber, and an exhaust system <b>11</b> is connected with exhaust port <b>26</b>. A mounting platform <b>28</b> on which a workpiece which is a semiconductor wafer W is mounted and held, is installed in the upper chamber of processing container <b>22</b>. A gas inlet <b>78</b> which introduces gas necessary for processing into the processing container is formed at a central portion of a ceiling part of the processing container <b>22</b>. A gas supply system <b>14</b> which supplies, for example, a source gas is connected with gas inlet <b>78</b>. A gas introduction mechanism <b>80</b> is communicated with gas inlet <b>78</b> to be installed at an upper portion of processing container <b>22</b>.

0043Exhaust system <b>11</b> has a configuration in which a turbo molecular pump <b>11</b>A and dry pump <b>11</b>B are connected in series, and nitrogen gas is supplied to turbo molecular pump <b>11</b>A through a valve <b>11</b><i>b</i>. Variable conductance valve <b>11</b><i>a </i>is installed between processing container <b>22</b> and turbo molecular pump <b>11</b>A to maintain the entire pressure inside the processing container <b>22</b> uniformly. An exhaust path <b>11</b>C which bypasses turbo molecular pump <b>11</b>A is installed to rough processing container <b>22</b> using dry pump <b>11</b>B and a valve <b>11</b><i>c </i>is installed at exhaust path <b>11</b>C, and a valve <b>11</b><i>d </i>is installed at downstream of turbo molecular pump <b>11</b>A. A trap mechanism (not illustrated) to remove remnants contained in an exhaust gas is installed at an upstream of dry pump <b>11</b>B. A heater for heating the exhaust gas, such as for example, a tape heater is installed at the exhaust path spanning to the trap mechanism of exhaust system <b>11</b> to maintain a non-reacted source gas contained in the exhaust gas at a temperature lower than the decomposition temperature of raw material and equal to or higher than the solidification temperature or liquefaction temperature, and the non-reacted source gas is recovered through the trap mechanism.

0044Gas supply system <b>14</b> includes a bubbler <b>14</b>A vaporizing the raw material and a gas introduction line <b>14</b>B guides the raw material to processing container <b>22</b>. Ru carbonyl compound such as Ru₃(CO)₁₂is maintained at inside bubbler <b>14</b>A as the raw material, and CO gas serving as a carrier gas is supplied from a bubbling gas line <b>14</b><i>a </i>in which a mass flow controller (MFC) <b>14</b><i>b </i>is intervened to be bubbled, so that the vaporized Ru₃(CO)₁₂gas can be introduced into processing container <b>22</b> through gas introduction line <b>14</b>B as the source gas. CO gas as a carrier gas can be flown from a line <b>14</b><i>d </i>in which mass flow controller (MFC) <b>14</b><i>c </i>is intervened, and the source gas is transported toward processing container <b>22</b> in gas introduction line <b>14</b>B by the carrier gas. A line <b>14</b><i>f </i>which supplies an inert gas such as Ar and in which valves <b>14</b><i>g</i>, <b>14</b><i>h </i>and MFC <b>14</b><i>e </i>are intervened is installed in gas supply system <b>14</b>A, and the inert gas may be added to Ru₃(CO)₁₂gas supplied from processing container <b>22</b> through gas introduction line <b>14</b>B as needed.

0045Mounting platform <b>28</b> is molded, for example, in a circular plate shape in its entirety and the diameter of mounting platform <b>28</b> is larger than that of semiconductor wafer W which is mounted on the upper surface of mounting platform <b>28</b>. Mounting platform <b>28</b> is attached and fixed to an upper end portion of a post <b>30</b> which is made of, for example, metal and erected from the bottom side of processing container <b>22</b>. Post <b>30</b> passes through the bottom forming the boundaries of exhaust space <b>24</b> to be extended downward and allows mounting the platform <b>28</b> to be lifted or lowered down entirely in a vertical direction by an actuator (not illustrated) to stop at a location. A bellows <b>32</b> made of metal to be extendable and contractible is installed at a penetrating part of post <b>30</b>, so that mounting platform <b>28</b> may be lifted or lowered down while maintaining airtightness.

0046A heater <b>34</b>, for example, a tungsten wire heater or a carbon wire heater as a heating unit for the workpiece is buried within mounting platform <b>28</b>, and semiconductor wafer W is heated by heater <b>34</b>. A refrigerant passage <b>36</b> through which refrigerant that cools the lower portion or side portion of mounting platform <b>28</b> to adjust a temperature thereof flows is installed below heater <b>34</b>. Details of mounting platform <b>28</b> will be described below.

0047A plurality of, for example, three pin insertion holes <b>37</b> are installed at the periphery of mounting platform <b>28</b> and each pin insertion hole <b>37</b> is formed to allow lifter pins <b>38</b> to be inserted into and passed through. An elevation arm <b>40</b> supports the lower end portion of each of lifter pins <b>38</b> and can be lifted or lowered down by an elevation rod <b>44</b> which penetrates the bottom of the container air-tightly in cooperation with bellows <b>42</b>. Lifter pins <b>38</b> protruded above mounting platform <b>28</b> to push wafer W upward or downward while mounting platform <b>28</b> is being lowered down to a mounting position of wafer W.

0048At a position where wafer W is lowered down, an opening <b>46</b> through which wafer W is carried in and out by a transfer arm (not illustrated) is formed and a gate valve <b>48</b> to open and close opening <b>46</b> is installed, at a side wall of the processing chamber corresponding to a horizontal level of the upper surface of mounting platform <b>28</b>.

0049The heaters <b>49</b>A and <b>49</b>B are installed at the side wall or the ceiling part of processing container <b>22</b> and the source gas is prevented from being solidified or liquefied by maintaining the side wall and the ceiling part at a predetermined temperature.

0050Mounting platform <b>28</b> as illustrated in <figref idref="DRAWINGS">FIGS. 3 and 4</figref> is primarily constituted with a mounting platform main body <b>50</b> having mounted semiconductor wafer W thereon, a base <b>52</b> supporting mounting platform main body <b>50</b> while surrounding a side surface and bottom surface of mounting platform main body <b>50</b>. Heater <b>34</b> is installed within mounting platform main body <b>50</b> and refrigerant path <b>36</b> is installed within base <b>52</b>. Base <b>52</b> is adapted to allow the refrigerant to flow in refrigerant passage <b>36</b> to maintain the mounting platform main body in a range of temperature lower than that of the decomposition temperature of the source gas and equal to or higher than the solidification temperature or liquefaction temperature. Pin insertion hole <b>37</b> or lifter pin <b>38</b> is omitted in <figref idref="DRAWINGS">FIG. 3</figref>.

0051Mounting platform main body <b>50</b> is made entirely of a ceramic material or metal and formed in a circular plate shape. Heater <b>34</b> is buried with being electrically insulated and approximately throughout the surface inside mounting platform main body <b>50</b>, so that the temperature of semiconductor wafer W directly mounted on and contacted with the upper surface of mounting platform main body <b>50</b> is controlled by heating semiconductor wafer W to a desired temperature.

0052As materials constituting mounting platform main body <b>50</b>, ceramic materials, such as, Aluminium nitride (AlN), Aluminium oxide (Al₂O₃), and Silicon carbide (SiC), and metal, such as, aluminium and aluminium alloy may be utilized. The diameter of mounting platform main body <b>50</b> is set to slightly smaller than that of semiconductor wafer W. For example, when a diameter of semiconductor wafer W is 300 mm, the diameter of mounting platform main body <b>50</b> is set to approximately 295 mm. A step portion <b>54</b> of which cross section is cut out in a right-angle shape is formed in a ring shape along the circumferential direction of mounting platform main body <b>50</b> in the peripheral edge thereof.

0053Base <b>52</b> is made entirely of metal. Base <b>52</b> is constituted with a base part <b>56</b> made of metal in a circular-plate shape in which refrigerant passage <b>36</b> is installed approximately throughout the entire inside surface thereof, and an edge ring <b>58</b> made of metal in a ring shape and installed to surround the circumferential surface of mounting platform main body <b>50</b> at the peripheral edge of base part <b>56</b>. For example, cooling water, Fluorinert and Galden (registered trademarks) serving as refrigerant are allowed to flow in refrigerant passage <b>36</b> through a pipe (not illustrated).

0054A ring-shaped thermal conduction relaxation member <b>60</b> made of metal having a low thermal conductivity is intervened between base part <b>56</b> and edge ring <b>58</b>. Specifically, base part <b>52</b> and edge ring <b>58</b> are made of aluminium and aluminium alloy, and ring-shaped thermal conduction relaxation member <b>60</b> is made of stainless steel having a lower thermal conductivity than that of aluminium or aluminium alloy. Ring-shaped thermal conduction relaxation member <b>60</b> may be installed as needed, otherwise omitted. Base part <b>56</b> and edge ring <b>58</b> may be made of stainless steel, in spite of having a lower thermal conductivity, instead of aluminium or aluminium alloy. Edge ring <b>58</b>, ring-shaped thermal conduction relaxation member <b>60</b> and base part <b>56</b> are integrally connected with each other to be detachable (decomposable) by a plurality of bolts <b>62</b> from above.

0055A thermal insulation material <b>64</b> has been intervened between the upper surface of base part <b>56</b> and the bottom (lower surface) of mounting platform main body <b>50</b> to thermally isolate base part <b>56</b> and mounting platform main body <b>50</b> from each other. The thermal insulation material <b>64</b> may be made of ceramic materials or stainless steel having a low conductivity as well as an excellent heat resistance.

0056Edge ring <b>58</b> includes a ring-shaped flange part <b>66</b> extending outwardly in a radial direction of semiconductor wafer W by a predetermined length while maintaining the same level as a horizontal level of a surface on which semiconductor wafer W is mounted. A projecting portion <b>66</b><i>a </i>protruding upwardly is formed circumferentially at the peripheral edge of flange part <b>66</b>.

0057A protrusion <b>68</b> protruding toward mounting platform main body <b>50</b> is formed in a ring shape along the circumferential direction of edge ring <b>58</b> at the upper portion of the inner peripheral side of edge ring <b>58</b>, and protrusion <b>68</b> extends to the middle of step portion <b>54</b> of mounting platform main body <b>50</b>. Protrusion <b>68</b> is provided with a fixing screw <b>70</b> penetrating downwardly and fixing screw <b>70</b> is screwed downwardly to press the neighboring components of mounting platform main body <b>50</b> to fix protrusion <b>68</b>. Therefore, the inner circumferential surface of edge ring <b>58</b> and the outer circumferential surface of mounting platform main body <b>50</b> are not directly contacted with each other, a space part <b>72</b> for thermally insulating is formed between edge ring <b>58</b> and the outer circumferential surface of mounting platform main body <b>50</b>. Fixing screws <b>70</b> are provided, for example, a total of six units, and increase the thermal insulation between edge ring <b>58</b> and mounting platform main body <b>50</b>.

0058A ring-shaped shield ring <b>74</b> is detachably installed between a side surface of step portion <b>54</b> of mounting platform main body <b>50</b> and the inner circumferential surface of protrusion <b>68</b> of edge ring <b>58</b> in a loosely fitted state. Ring-shaped shield ring <b>74</b> is made of metal such as aluminium and aluminium alloy, and has the functions of preventing of film deposition on the sidewalls of mounting platform main body <b>50</b>, securing the in-plane temperature uniformity of semiconductor wafer W, preventing the film deposition on the rear surface of semiconductor wafer W, and a thermal insulation between edge ring <b>58</b> and mounting platform main body <b>50</b>.

0059A ring-shaped cover ring <b>76</b> for preventing a film from being adhered to the bevel part corresponding to a cross-section of semiconductor wafer W is installed at the upper surface of the edge ring <b>58</b>. Cover ring <b>76</b> is made of ceramic material, such as for example, alumina or aluminium nitride. Similar to base <b>52</b>, a temperature of cover ring <b>76</b> is also maintained to be lower than the decomposition temperature of the source gas and equal to or higher than the solidification temperature or liquefaction temperature during the film deposition.

0060A gas introduction mechanism <b>80</b> is communicated with a gas inlet <b>78</b> installed at the central portion of the ceiling part of processing container <b>22</b>, and installed to oppose mounting platform <b>28</b>. Therefore, the source gas is discharged and ejected toward an area further outside than the outer peripheral end of semiconductor wafer W on mounting platform <b>28</b> from above in the vertical direction of mounting platform <b>28</b>. Therefore, gas introduction mechanism <b>80</b> supplies the source gas to the exterior portion of semiconductor wafer W mounted on mounting platform <b>28</b> in a direction where the source gas is avoided from being supplied.

0061Specifically, gas introduction mechanism <b>80</b> includes a baffle plate <b>82</b> having a diameter larger than that of semiconductor wafer W, and baffle plate <b>82</b> is supported to be spaced apart by an appropriate distance by the a circular type ring-shaped support member <b>84</b> extending downwardly from inner surface of the ceiling part of processing container <b>22</b>. Therefore, baffle plate <b>82</b> is attached to be opposed to semiconductor wafer W on mounting platform <b>28</b>.

0062Peripheral edge of the baffle plate <b>82</b> as illustrated in <figref idref="DRAWINGS">FIG. 2</figref> is provided with a plurality of gas discharge ports <b>86</b> formed in an arc shape along the circumferential direction of baffle plate <b>82</b>. The plurality of gas exhaust ports <b>86</b> are formed at above the area further outside than the peripheral end of semiconductor wafer W on mounting platform <b>28</b> in the vertical direction thereof. A portion between the ceiling part of processing container <b>22</b> and baffle plate <b>82</b> is formed as a diffusion chamber <b>88</b> in which the source gas is diffused, and the source gas diffused outwardly from the diffusion chamber <b>88</b> is discharged or injected toward processing space S formed below from the plurality of gas discharge ports <b>86</b>.

0063As described above, since a place right under gas discharge ports <b>86</b> corresponds to the area further outside than the peripheral end of semiconductor wafer W, the source gas is discharged toward the outer area of semiconductor wafer W, so that the source gas is not allowed to directly flow on the upper surface of semiconductor wafer W.

0064A plurality of gas injection ports having a smaller inner diameter may be formed along the circumferential direction instead of the arc shaped gas discharge ports <b>86</b>.

0065Support member <b>84</b> or baffle plate <b>82</b> is made of a metal material, such as for example, aluminium or aluminium alloy, having an excellent thermal conductivity.

0066A ring-shaped internal partition wall <b>90</b> extends downwardly from support member <b>84</b> to be installed at the lower part thereof. Internal partition wall <b>90</b> is integrally formed with support member <b>84</b> to be in continuous therewith, and made of the same material as the support member <b>84</b>. Internal partition wall <b>90</b> is installed to surround processing space S above mounting platform <b>28</b> and the lower end portion of internal partition wall <b>90</b> is provided closely to mounting platform <b>28</b>. A gas outlet <b>92</b> for exhausting is formed in a circular shape along the circumferential direction of mounting platform <b>28</b> between the lower end portion of internal partition wall <b>90</b> and the peripheral edge of mounting platform <b>28</b>. An atmosphere inside processing space S is uniformly exhausted from the outer peripheral side of wafer W.

0067Internal partition wall <b>90</b> is positioned above cover ring <b>76</b> and flange part <b>66</b> positioned at the peripheral edge of mounting platform <b>28</b>, gas outlet <b>92</b> is formed between the top surface of cover ring <b>76</b> (including the top surface of flange part <b>66</b>) and the lower end surface of internal partitioning wall <b>90</b>. A protrusion <b>94</b> formed in a ring shape is formed at a position corresponding to projecting portion <b>66</b><i>a </i>of flange part <b>66</b> along the circumferential direction of internal partitioning wall <b>90</b> in the lower end portion thereof to further narrow the flow width of outer peripheral side <b>92</b>. The width L<b>1</b> of gas outlet <b>92</b> in the vertical direction is set in a range of 2 mm to 19.5 mm, for example, set to about 5 mm (see <figref idref="DRAWINGS">FIG. 4</figref>).

0068An orifice forming member <b>96</b> is installed at the lower end portion of internal partitioning wall <b>90</b>. Specifically, orifice forming member <b>96</b> is installed at the lower end portion of internal partitioning wall <b>90</b> to be extended more inwardly toward the radial direction of mounting platform <b>28</b> than internal partitioning wall <b>90</b>, and is formed in a ring shape along the circumferential direction of mounting platform <b>28</b>. An orifice <b>98</b> communicating with gas outlet <b>92</b> is formed between the bottom surface of orifice forming member <b>96</b> and the peripheral edge of mounting platform <b>28</b>. Therefore, orifice <b>98</b> is formed to be partitioned between the bottom surface of orifice forming member <b>96</b> and the top surface of cover ring <b>76</b> disposed at the peripheral edge of mounting platform <b>28</b>, and formed in a ring shape along the circumferential direction of mounting platform <b>28</b>.

0069The material of orifice forming member <b>96</b> is made of the material as in internal partitioning wall <b>90</b>, such as for example, aluminium or aluminium alloy, having an excellent thermal conductivity, and herein, orifice forming member <b>96</b> and internal partitioning wall <b>90</b> are integrally formed with each other. As described above, orifice forming member <b>96</b> is installed to extend in the central direction of processing container <b>22</b> to make a portion of the source gas flown down from above to flow toward the central direction of processing container <b>22</b>. In addition, an area of the flow path of an atmosphere exhausted by orifice <b>98</b> is made narrower to appropriately lengthen a staying time of the source gas in processing space S.

0070In this case, the inner peripheral end of orifice forming member <b>96</b> is set to a position located between a place above the outer peripheral end of semiconductor wafer W mounted on mounting platform <b>28</b> and a position more spaced apart than the place by 10 mm outwardly in a radial direction of mounting platform <b>28</b>. Specifically, in <figref idref="DRAWINGS">FIG. 4</figref>, a distance L<b>2</b> (a distance when viewed from the vertical direction) in the horizontal direction between the outer peripheral end of semiconductor wafer W and the inner peripheral end of orifice forming member <b>96</b> is set to be in a range between 0 (zero) mm to 10 mm. When the inner peripheral end of orifice forming member <b>96</b> is lengthened to be located over wafer W, the in-plane uniformity of the film thickness is undesirably reduced. Further, if the length L<b>2</b> becomes larger than 10 mm, the installation effect of orifice <b>98</b> is reduced so that the deposition rate is decreased. The width of orifice <b>98</b> in the vertical direction L<b>3</b> (see <figref idref="DRAWINGS">FIG. 4</figref>) is set to be in a range of 2 mm to 19.5 mm, for example, 5 mm, which is the same as the width L<b>1</b> of gas outlet <b>92</b>.

0071The diameter D (see <figref idref="DRAWINGS">FIG. 1</figref>) of the central portion of baffle plate <b>82</b> which does not form gas discharge port <b>86</b> of baffle plate <b>82</b> has a magnitude equal to or higher than that of wafer W. For example, when a wafer W having a diameter of 300 mm is subjected to the deposition processing, the diameter D of 300 mm or more is required. The distance G between baffle plate <b>82</b> and wafer W is set to be in a range of, for example, 25 mm to 67 mm.

0072Mounting platform <b>28</b> is disposed on a location as illustrated in <figref idref="DRAWINGS">FIG. 4</figref> when being subjected to the deposition processing, but lowered down as illustrated in <figref idref="DRAWINGS">FIG. 5</figref> when being subjected to other processings, such as for example, carrying in and out of semiconductor wafer W.

0073The control of overall operations of the deposition device, such as for example, starting and stopping of gas supply, and the control of process temperature, process pressure, and temperature of the refrigerant flowing in refrigerant passage <b>36</b>, may be performed by a device control unit <b>100</b> constituted by, for example, a computer.

0074A computer-readable program necessary for controlling the deposition processing in deposition device <b>20</b> is stored in a storage medium <b>102</b>, and a flexible disk, Compact Disk (CD), CD-ROM, a hard disk, a flash memory or DVD may be used as storage medium <b>102</b>.

0075Next, the deposition processing performed by deposition device <b>20</b> having a configuration as described above will be described with reference to <figref idref="DRAWINGS">FIGS. 6A and 6B</figref>. <figref idref="DRAWINGS">FIGS. 6A and 6B</figref> are diagrams illustrating the flow of a source gas within processing container <b>22</b>, <figref idref="DRAWINGS">FIG. 6B</figref> is an enlarged diagram illustrating the surrounding portions of the orifice in <figref idref="DRAWINGS">FIG. 6A</figref>.

0076First, semiconductor wafer W is transported into processing container <b>22</b> to be mounted on mounting platform <b>28</b> in deposition device <b>20</b>. The inside of processing container <b>22</b> is maintained at a predetermined pressure by being subjected to a vacuum treatment in accordance with a continuous driving of exhaust system <b>11</b>. Semiconductor wafer W supported at mounting platform <b>28</b> is maintained at a predetermined temperature by heater <b>34</b>.

0077The side wall of processing container <b>22</b>, the ceiling part, support member <b>84</b>, internal partition wall <b>90</b> and orifice forming member <b>96</b> are also maintained at a predetermined temperature by heaters <b>49</b>A and <b>49</b>B, respectively. The predetermined temperature is in a range lower than the decomposition temperature of raw material and equal to or higher than the solidification temperature or liquefaction temperature, and these elements are heated to, for example, about 80° C., respectively.

0078The source gas (Ru₃(CO)₁₂) is supplied by gas supply system <b>14</b> together with CO gas serving as a carrier gas under the temperature condition as described above, and the source gas and the carrier gas are introduced into diffusion chamber <b>88</b> from the gas inlet <b>78</b>.

0079The source gas introduced is diffused toward the periphery of diffusion chamber <b>88</b> due to the presence of baffle plate <b>82</b> and discharged toward downward from each of gas discharge ports <b>86</b> installed at the periphery of baffle plate <b>82</b> to flow-down into processing space S as indicated by the arrows <b>110</b> (see <figref idref="DRAWINGS">FIG. 6</figref>). The direction of the flowing-down is toward an area outer side of outer peripheral end of wafer W corresponding to the peripheral end of mounting platform <b>28</b>. A portion of the source gas is diffused toward the central portion of processing space S in the middle of the flowing-down process as indicated by the arrow <b>112</b> (see <figref idref="DRAWINGS">FIG. 6A</figref>) and stays therein.

0080Simultaneously, most of the source gas having been flowed-down comes in contact with orifice forming member <b>96</b> installed to be extended toward the central portion of processing space S at the lower end of internal partition wall <b>90</b>, and deflects toward the central portion of processing space S. A portion of the source gas having been deflected stays in processing space S, while most of the source gas flows inside orifice <b>98</b> in which flow path area is made narrower and passes through gas outlet <b>92</b> to flow into a space formed at below mounting platform <b>28</b> in processing container <b>22</b> as indicated by the arrow <b>115</b>. The atmosphere within processing container <b>22</b> passes through exhaust port <b>26</b> to be exhausted outside processing container <b>22</b>. The source gas supplied to semiconductor wafer W in processing space S is thermally decomposed on semiconductor wafer W to form a Ru film by CVD. The reaction of the film deposition at the time of forming the Ru film is represented by the following chemical formula, and carbon monoxide (CO) which is the same gas species as the carrier gas is generated by the reaction.

0000<br />Ru₃(CO)₁₂<img file="US2013000558A1_D0001.tif" />Ru₃(co)₁₂↑

0000<br />Ru₃(CO)₁₂↑<img file="US2013000558A1_D0002.tif" />Ru₃(CO)_12-X↑+XCO↑

0000<br />Ru₃(CO)_12-X↑+Q→3Ru+(12-X)CO↑

0000<br />Ru₃(CO)₁₂↑+Q→3Ru+12CO↑

0081In the chemical formula, the symbol “<img file="US2013000558A1_D0003.tif" />” represents that the reaction is reversible, “↑” represents that the compound is in a gaseous state, the compound to which the arrow “↑” is not given represents that it is in a solid state, and the “Q” represents a state in which a heat is being applied during the reaction.

0082As described above, since orifice <b>98</b> of which flow path area is appropriately made narrower is installed, the source gas is stayed within processing space S for a suitable time, and further, the amount of source gas residing in the central portion of processing space S does not become excessive, and the atmosphere in processing space S is discharged through orifice <b>98</b> and gas outlet <b>92</b>. That is, a concentration of the source gas residing in the central portion of processing space S always maintained to be lower than that resides in the periphery thereof, and the source gas contained in processing space S is allowed to be stayed appropriately while maintaining such concentration conditions as described above.

0083That is, in a configuration of the Patent Document 3 in which a gas outlet <b>192</b> is simply installed between internal partition wall <b>90</b> and mounting platform <b>28</b> without installing the orifice as illustrated in <figref idref="DRAWINGS">FIG. 7</figref>, the source gas flowed-down from gas discharge port <b>86</b> as indicated by the arrow <b>110</b> is discharged from gas outlet <b>192</b> as it is as indicated by the arrow <b>114</b><i>a</i>. Therefore, an amount of the source gas contributing to the film deposition becomes small so that the deposition rate tends to be low. However, in the first embodiment, since the staying time of the source gas within processing space S can be extended appropriately due to the presence of the orifice <b>98</b> in which flow rate area is appropriately made narrower, it is possible to increase the deposition rate of the Ru film without damaging the in-plane uniformity of film thickness. Therefore, in the embodiment, it is possible to deposit Ru film at a higher film deposition rate than the related art while maintaining the high in-plane uniformity of film thickness.

0084In this case, the process conditions are as follows: the process pressure is in a range of 0.001 Torr to 1 Torr, for example, 0.1 Torr; wafer W temperature is equal to or higher than the decomposition temperature of the source gas, for example, in a range of 150° C. to 250° C., for example, about 190° C. The flow rate of the source gas is 1 sccm to 2 sccm and the flow rate of CO gas as the carrier gas is 100 sccm. The temperatures of orifice forming member <b>96</b>, internal partition wall <b>90</b> and cover ring <b>76</b> at the peripheral edge of mounting platform <b>28</b> are set to be lower than the decomposition temperature of raw material and equal to or higher than the solidification temperature or liquefaction temperature, for example, 80° C. Therefore, an unnecessary film is not deposited on the surfaces of those constitutional members.

0085As described above, the first aspect of the present invention provides a deposition device for forming a thin film on semiconductor wafer W which is a workpiece, using a source gas including an organometallic compound, the deposition device including: processing container <b>22</b> which is exhaustible and in which semiconductor wafer W which is a workpiece is accommodated; mounting platform <b>28</b> having mounted semiconductor wafer W thereon and installed with heater <b>34</b> for heating semiconductor wafer W; gas introduction mechanism <b>80</b> disposed above mounting platform <b>28</b> to be opposed thereto and configured to introduce the source gas toward the area further outside than the outer peripheral end of semiconductor wafer W on mounting platform <b>28</b>; internal partition wall <b>90</b> which surrounds processing space S above mounting platform <b>28</b> to form a boundary for processing space S and installed such that the lower end portion of the internal partition wall comes close to mounting platform <b>28</b> to form gas outlet <b>92</b> between the lower end portion of the internal partition wall and the peripheral edges of mounting platform <b>28</b>; and orifice forming member <b>96</b> installed on the lower end of internal partition wall <b>96</b> to extend radially inward toward mounting platform <b>28</b> to form orifice <b>98</b> communicating with gas outlet <b>92</b> between the internal partition wall and the peripheral edge of mounting platform <b>28</b>. Therefore, it is possible to increase the deposition rate while maintaining a high in-plane uniformity of the film thickness.

Deposition Device According to Second Embodiment

0086A deposition device according to a second embodiment of the present disclosure will be described. <figref idref="DRAWINGS">FIG. 8</figref> is a partially enlarged cross-sectional view illustrating a portion of the deposition device according to the second embodiment of the present invention, and <figref idref="DRAWINGS">FIG. 9</figref> is a side view illustrating the portion of the mounting platform in the deposition device of the <figref idref="DRAWINGS">FIG. 8</figref>. In addition, the portions not illustrated in <figref idref="DRAWINGS">FIGS. 8 and 9</figref> have the same configuration as that of the first embodiment. <figref idref="DRAWINGS">FIG. 8</figref> corresponds to <figref idref="DRAWINGS">FIG. 4</figref> in the first embodiment, and the same reference numerals are given to the same constitutional elements as those illustrated in <figref idref="DRAWINGS">FIG. 4</figref>, and description thereof will be omitted.

0087In the above-described first embodiment, orifice forming member <b>96</b> is formed to be integral with internal partition wall <b>90</b>. However, in the second embodiment, an orifice forming member <b>116</b> formed to be thinner than orifice forming member <b>96</b> of the first embodiment, and molded in a thin plate-type circular ring shape in which the width in the radial direction is set to be larger than that of the first embodiment is provided. The thickness of the orifice forming member <b>116</b> having a thin plate-type circular ring shape is set to smaller than a width L<b>1</b> of gas outlet <b>92</b>. Orifice forming member <b>116</b> is installed to be inserted into gas outlet <b>92</b> between internal partition wall <b>90</b> and mounting platform <b>28</b>, and an upper gap <b>92</b>A and a lower gap <b>92</b>B are formed at above and below orifice forming member <b>116</b>, respectively. Upper gap <b>92</b>A is adapted to serve as an orifice <b>118</b> which is formed in a ring shape along the circumferential direction of mounting platform <b>28</b> as in orifice forming member <b>98</b> in the first embodiment.

0088Similar to the first embodiment, an inner peripheral end of orifice forming member <b>116</b> is installed to be extended inwardly toward mounting platform <b>28</b>. The outer peripheral end of orifice forming member <b>116</b> is supported in a state of being suspended by a plurality of support arms <b>120</b> disposed to be spaced apart at a predetermined interval along the circumferential direction of internal partition wall <b>90</b> at the lower end portion thereof (see <figref idref="DRAWINGS">FIG. 9</figref>).

0089A total of, for example, about 6 (six) support arms <b>120</b> are simply installed having almost no effect on the exhausting of gas. Support arms <b>120</b> are also made of material such as aluminium or aluminium alloy, having an excellent thermal transmitivity similar to orifice forming member <b>116</b>, and set to a temperature, for example, about 80° C., lower than the decomposition temperature of the source gas and equal to or higher than the solidification temperature or liquefaction in the first embodiment so that a thin film is not adhered on the surface of support arms <b>120</b>. Protrusion <b>94</b> installed at gas outlet <b>92</b> in the first embodiment is not installed in the second embodiment.

0090Both the width L<b>1</b>A of upper gap <b>92</b>A and width L<b>1</b>B of lower gap <b>92</b>A in vertical direction are about 1 mm to 5 mm, respectively. The distance L<b>2</b> (a distance when viewed from the vertical direction) between the inner peripheral end of orifice forming member <b>116</b> and outer peripheral end of wafer W in the horizontal direction is set to be in a range of 0 mm to 10 mm as in the first embodiment. The reason of such a setting for the distance L<b>2</b> is the same as in the first embodiment.

0091Herein, cover ring <b>76</b> installed on edge ring <b>58</b> is divided into an inner side ring <b>76</b>A and outer side ring <b>76</b>B, and a minute gap is formed between both side rings <b>76</b>A and <b>76</b>B. A purge gas supply mechanism <b>126</b> is installed to supply a gas, serving as a purge gas which is the same kind as that of the carrier gas, to lower gap <b>92</b>B through a gap <b>122</b>. Specifically, purge gas supply mechanism <b>126</b> has a gas groove <b>124</b> formed in a ring shape along the circumferential direction of edge ring <b>58</b> at edge ring <b>58</b> corresponding to gap <b>122</b>. Gas groove <b>124</b> is connected to a gas flow path <b>128</b> formed to pass through post <b>30</b> and mounting platform <b>28</b>. Specifically, gas flow path <b>128</b> is adapted to extend into post <b>30</b> vertically, into base part <b>56</b> of base <b>52</b> in mounting platform <b>28</b> horizontally, and into edge ring <b>58</b> vertically to reach gas groove <b>124</b>. A flow rate controller <b>13</b>, such as mass flow controller or an opening and closing valve <b>132</b>, is intervened in gas flow path <b>128</b>, and adapted to supply CO gas as the purge gas while controlling CO gas flow rate as needed.

0092<figref idref="DRAWINGS">FIG. 10</figref> is a diagram illustrating the flow of a source gas within a processing container in the deposition device of the second embodiment, and corresponds to <figref idref="DRAWINGS">FIGS. 6A and 6B</figref> in the first embodiment. In the second embodiment, a portion of the source gas having been flowed-down from gas discharge port <b>86</b> (see <figref idref="DRAWINGS">FIG. 1</figref>) of baffle plate <b>82</b> in the vertical direction as indicated by the arrow <b>110</b> is diffused toward the central portion of mounting platform <b>28</b> to stay in the processing container as indicated by the arrow <b>122</b> as in the first embodiment. A flow path area of a portion of the source gas having been flowed-down further in the vertical direction is made narrower at the orifice <b>118</b> corresponding to upper gap <b>92</b>A of gas outlet <b>92</b> to be discharged as indicated by the arrow <b>140</b>.

0093Further, the other portion of the source gas being flowed-down comes in contact with an upper surface of the peripheral edge inside orifice forming member <b>116</b> and thus temporarily flows towards the central portion of mounting platform <b>28</b> and then returns therefrom to be flown-out through orifice <b>118</b>. By doing this, the source gas contained in processing space S temporarily stays therein and simultaneously flows in orifice <b>118</b> whose flow path area is made narrower to be flown-out toward below mounting platform <b>28</b> as indicated by the arrow <b>144</b>.

0094As described above, since orifice <b>98</b> of which flow path area is appropriately made narrower is installed, the source gas stays within processing space S for a suitable time, and further, the amount of source gas residing in the central portion of processing space S does not become excessive, and the atmosphere in processing space S is discharged through orifice <b>118</b> and gas outlet <b>92</b>. That is, the concentration of the source gas residing in the central portion of processing space S always maintained to be lower than that residing in the periphery thereof, and the source gas contained in processing space S is allowed to be stayed appropriately while maintaining such concentration conditions as described above. As a result, as in the first embodiment, it is possible to deposit Ru film at a high deposition rate while maintaining a high in-plane uniformity of the film thickness.

0095In the second embodiment, when a film deposition is conducted as described above, the purge gas of which flow rate is controlled is supplied into flow path <b>128</b> of purge gas supply mechanism <b>126</b>. The purge gas is flowed into lower gap <b>92</b>B installed below orifice forming member <b>116</b> from gas groove <b>124</b> formed in a ring shape. A portion of the purge gas flowed into lower gap <b>92</b>B is sucked-in to be flown toward outward as indicated by the arrow <b>146</b>. The remaining purge gas flows toward processing space S as indicated by the arrow <b>148</b>, but in this case, interferes with the flow of the source gas intending to flow into lower gap <b>92</b>B to be collided therewith, so that it is possible to prevent the source gas from being flown into lower gap <b>92</b>B.

0096Therefore, it is possible to prevent an unnecessary film from being deposited on a surface of the peripheral edge of mounting platform <b>28</b>, specifically, the surfaces of cover ring <b>76</b> and edge ring <b>58</b>. In addition, since CO gas which is the same kind as the carrier gas is utilized as the purge gas and the CO gas acts to suppress the decomposition of the source gas, it is possible to further improve the prevention of the unnecessary film deposition. In this case, when the larger amount of CO gas is flown into processing space S than lower gap <b>92</b>B to reach the peripheral edge of semiconductor wafer W, the film deposition at the top surface of the peripheral edge of semiconductor wafer W is deteriorated, and thus, it is undesirable. Therefore, it is preferable that the flow rate of the CO gas is set to be very small and the flow rate of the purge gas as indicated by the arrow <b>148</b> is preferably set to an order of an amount not being allowed to escape toward processing space S.

0097As described above, the second aspect of the present invention provides a deposition device for forming a thin film on a semiconductor wafer W which is a workpiece using a source gas including an organometallic compound, the deposition device including: processing container <b>22</b> which is vacuum exhaustible in which semiconductor wafer W which is a workpiece is accommodated; mounting platform <b>28</b> having mounted semiconductor wafer W thereon and installed with heater <b>34</b> for heating semiconductor wafer W; gas introduction mechanism <b>80</b> disposed above mounting platform <b>28</b> to be opposed thereto and configured to introduce the source gas toward the area further outside than the outer peripheral end of semiconductor wafer W on mounting platform <b>28</b>; internal partition wall <b>90</b> configured to surround processing space S above mounting platform <b>28</b> to form a boundary for processing space S and installed such that the lower end portion of the internal partition wall comes close to mounting platform <b>28</b> to form gas outlet <b>92</b> between the lower end portion of the internal partition wall and the peripheral edges of mounting platform <b>28</b>; and orifice forming member <b>116</b> intervened to form upper gap <b>92</b>A and a lower gap <b>92</b>B in gas outlet <b>92</b>, the inner peripheral end is disposed to extend radially inward toward mounting platform <b>28</b>, and upper gap <b>92</b>A forms orifice <b>98</b>. Therefore, it is possible to increase the deposition rate while maintaining a high in-plane uniformity of the film thickness. Furthermore, since the purge gas is allowed to flow in lower gap <b>92</b>B, it is possible to suppress the deposition of the film on the peripheral edge of mounting platform <b>28</b>. As a result, a higher deposition rate can be achieved than the first embodiment.

Evaluation of Experiment of First Embodiment and Second Embodiment

0098The results obtained by conducting the evaluation of experiment for the deposition devices of the first and second embodiments will be described. Further, for comparison purposes, an experiment was conducted for a conventional deposition device having no orifice (see <figref idref="DRAWINGS">FIG. 7</figref>).

0099In the conventional deposition device, the width of gas outlet <b>192</b> (see <figref idref="DRAWINGS">FIG. 7</figref>) of the lower end of internal partition wall <b>90</b> in the vertical direction was set to 2 mm. In the deposition device of the first embodiment, both the width L<b>1</b> of gas outlet <b>92</b> and the width L<b>3</b> of orifice <b>98</b> in the vertical direction were set to 2 mm, and the distance L<b>2</b> was set to 10 mm (see <figref idref="DRAWINGS">FIG. 4</figref>). Further, in the deposition device of the second embodiment, the width L<b>1</b>A of orifice <b>118</b> (upper gap <b>92</b>A) in the vertical direction was set to 3 mm, the width L<b>1</b>B of lower gap <b>92</b>B was set to 2 mm, and the distance L<b>2</b> was set to 8 mm (see <figref idref="DRAWINGS">FIG. 8</figref>). In addition, the flow rate of the CO gas of the purge gas supply mechanism <b>126</b> was set to 100 sccm. All other process conditions are set to be the same to deposit Ru film.

0100The results under the above-described conditions are represented in <figref idref="DRAWINGS">FIG. 11</figref>. <figref idref="DRAWINGS">FIG. 11</figref> is a graph illustrating a relationship between the deposition rate and in-plane uniformity in the deposition devices according to the first and second embodiments of the present invention and the related art. As illustrated in <figref idref="DRAWINGS">FIG. 11</figref>, the deposition rate of the related art was 1.93 nm/min, while those of the first embodiment and second embodiment are 2.17 nm/min and 2.66 nm/min, respectively. Accordingly, it was confirmed that higher deposition rates than that obtained in the related art can be obtained in the first and second embodiments. Specifically, it was confirmed that the deposition rates can be significantly improved by the deposition device in the second embodiment.

0101The in-plane uniformity according to the related art was about 6%. In contrast, it was confirmed that although the uniformities of the thicknesses in the first and second embodiments was decreased, both of the uniformities of the thicknesses were within an allowable range, which is a limit value of 10% or less.

Deposition Device According to Third Embodiment

0102Next, a deposition device according to a third embodiment of the present invention will be described. <figref idref="DRAWINGS">FIG. 12</figref> is a partially enlarged cross-sectional view illustrating a portion of the deposition device according to a third embodiment of the present invention. In addition, the portions not illustrated in <figref idref="DRAWINGS">FIG. 12</figref> have the same configuration as that of the first embodiment. The configuration illustrated in <figref idref="DRAWINGS">FIG. 12</figref> corresponds to that illustrated in <figref idref="DRAWINGS">FIG. 8</figref> of the second embodiment, and the same reference numerals are given to the same constitutional elements as those illustrated in <figref idref="DRAWINGS">FIG. 8</figref>, and description thereof will be omitted.

0103In the second embodiment, edge ring <b>58</b> and shield ring <b>74</b> of mounting platform <b>28</b> are installed to be thermally isolated from mounting platform main body <b>50</b>, and the temperatures of edge ring <b>58</b> and shield ring <b>74</b> are maintained at a temperature of, for example, 80° C., lower than the decomposition temperature of the source gas and equal to or higher than the solidification temperature or liquefaction temperature and the purge gas is allowed to flow in lower gap <b>92</b>B to prevent the deposition of an unnecessary film on edge ring <b>58</b>, cover ring <b>76</b> and shield ring <b>74</b> of the peripheral edge of mounting platform <b>28</b>. However, in this configuration, since the temperature of the peripheral edge of the mounting platform <b>28</b> is lower than a film deposition temperature, and also, the purge gas having a temperature lower than the film deposition temperature reaches the peripheral edge of semiconductor wafer W, an in-plane uniformity of the thickness obtained according to the second embodiment has a limitation.

0104Therefore, the third embodiment is configured such that the film deposition on the peripheral edge of mounting platform <b>28</b> can be prevented, and the in-plane uniformity of the thickness can be further improved as well.

0105In the third embodiment, a peripheral ring member is constituted by a shield ring <b>74</b>′ and an edge ring <b>58</b>′. Specifically, instead of shield ring <b>74</b> of the second embodiment, shield ring <b>74</b>′ having a wider width and being partially contacted to mounting platform main body <b>50</b> heated to a deposition temperature is installed, and instead of edge ring <b>58</b> of the second embodiment, edge ring <b>58</b>′ being partially contacted to mounting platform main body <b>50</b> is installed.

0106Shield ring <b>74</b>′ is installed so that a minute gap is formed between the inner peripheral surface thereof and the outer peripheral surface of mounting platform main body <b>50</b>. Further, a contacting protrusion <b>74</b><i>a </i>is installed at a portion of mounting platform main body <b>50</b> side of the bottom surface of shield ring <b>74</b>′ to be protruded downward and the bottom surface of contacting protrusion <b>74</b><i>a </i>is formed as a contacting portion <b>74</b><i>b </i>contacting the top surface of step portion <b>54</b> of mounting platform main body <b>50</b>. By doing this, shield ring <b>74</b>′ is heated due to a heat transfer from mounting platform main body <b>50</b>. Shield ring <b>74</b>′ is made of metal, such as for example, aluminium or aluminium alloy and is temperature-adjusted to become (e.g., lower than 10° C.) nearly equal to or slightly lower than that of semiconductor wafer W according to the above-mentioned configuration. The temperature of shield ring <b>74</b>′ is adjusted by adjusting a contact area of contacting portion <b>74</b><i>b </i>of contacting protrusion <b>74</b><i>a. </i>

0107A step portion <b>68</b>′ is formed at an inner upper portion of edge ring <b>58</b>′. A minute gap is formed between an inner peripheral surface of step portion <b>68</b>′ and the outer peripheral surface of shield ring <b>74</b>. The bottom surface of step portion <b>68</b>′ contacts the top surface of step portion <b>54</b> of mounting platform main body <b>50</b> and is formed as a contacting portion <b>68</b><i>a</i>. Edge ring <b>58</b>′ is made of metal, such as for example, aluminium or aluminium alloy and is temperature-adjusted to become nearly equal to or slightly lower than that of semiconductor wafer W according to the above-mentioned configuration (e.g., lower than 10° C.). The temperature of edge ring <b>58</b>′ is adjusted by adjusting a contact area of contacting portion <b>68</b><i>a </i>of step portion <b>68</b>′. Edge ring <b>58</b>′, thermal conduction relaxation member <b>60</b> and base member <b>56</b> are coupled to each other by a plurality of bolts (not illustrated). A gap may be formed between edge ring <b>58</b>′ and base member <b>56</b> instead of installing thermal conduction relaxation member <b>60</b>, and both the gap and thermal conduction relaxation member <b>60</b> may be installed.

0108In addition, shield ring <b>74</b>′ and edge ring <b>58</b>′, instead of being directly contacted to mounting platform main body <b>50</b> using contacting portion <b>74</b><i>b </i>and contacting portion <b>68</b><i>a</i>, may be partially contacted to mounting platform main body <b>50</b> through an intervening metal material having an excellent thermal transmitivity, such as for example, a spacer member having a low thermal heat resistance made of, for example, aluminium or copper. The temperatures of shield ring <b>74</b>′ and edge ring <b>58</b>′ may become a predetermined temperature lower than that of mounting platform main body <b>50</b> in any way which allowing shield ring <b>74</b>′ and edge ring <b>58</b>′ to be partially contacted to mounting platform main body <b>50</b> having a highest temperature.

0109As a result, the temperatures of shield ring <b>74</b>′ and edge ring <b>58</b>′ become lower than that of mounting platform main body <b>50</b>. However, when the Ru film is formed with Ru₃(CO)₁₂as a source gas, mounting platform main body <b>50</b> is heated to a temperature of about 215° C., semiconductor wafer W is heated to a temperature of about 190° C., and shield ring <b>74</b>′ and edge ring <b>58</b>′ are heated to a temperature of about 180° C. to about 190° C.

0110In the third embodiment, a cover member <b>164</b> including a material, such as aluminium having a high thermal transitivity, is installed to cover the outer peripheral side (a side opposing processing chamber <b>22</b>) of edge ring <b>58</b>′. Cover member <b>164</b> is installed so that a lower end portion thereof is pressed between thermal conduction relaxation member <b>60</b> and base member <b>56</b>, and an upper end portion thereof is attached to edge ring <b>58</b>′ by allowing an intervening thermal insulation material <b>166</b> to be intervened. Cover member <b>164</b> is maintained at a temperature, for example, about 80° C., which is close to that of base member <b>56</b>, lower than the decomposition temperature of the source gas and equal to or higher than the solidification temperature or liquefaction temperature.

0111In the third embodiment, a purge gas supply mechanism <b>126</b>′ capable of supplying a much higher temperature purge gas is installed instead of purge gas supply mechanism <b>126</b> of the second embodiment. Purge gas supply mechanism <b>126</b>′ includes a gas flow path <b>182</b> including a flow path (not illustrated) of post <b>30</b>, a flow path <b>172</b> between mounting platform main body <b>50</b> and thermal insulation material <b>64</b>, a flow path <b>174</b> connected to flow path <b>172</b> to vertically extend in step portion <b>54</b> of mounting platform main body <b>50</b>, a flow path <b>176</b> between shield ring <b>74</b>′ and step portion <b>54</b>, a flow path <b>178</b> between shield ring <b>74</b>′ and edge ring <b>58</b>′, and a flow path <b>180</b> between edge ring <b>58</b>′ and inner peripheral ring <b>76</b>A of cover ring <b>76</b>. Flow path <b>180</b> is connected to the gap between inner peripheral ring <b>76</b>A and outer peripheral ring <b>76</b>B. Therefore, the purge gas flows in flow path <b>182</b> is heated by mounting platform main body <b>50</b>, shield ring <b>74</b>′ and edge ring <b>58</b>′, and supplied to gap <b>92</b>B at a temperature equal to or slightly lower than that of semiconductor wafer W, for example, about 170° C.

0112In addition to forming a gap serving as a gas flow path by dividing cover ring <b>76</b> into inner peripheral ring <b>76</b>A and outer peripheral ring <b>76</b>B, a temperature gradient is formed by, for example, making those rings with different materials. Cover ring <b>76</b> may be divided into 3 (three) parts or more. Inner peripheral ring <b>76</b>A and outer peripheral ring <b>76</b>B may be made of ceramics, such as for example, alumina or aluminium nitride, and metal, such as for example, aluminium or aluminium alloy, and may also be made of either the same material or different materials. For example, inner peripheral ring <b>76</b>A and outer peripheral ring <b>76</b>B may be made of ceramics and aluminium, respectively. Since cover ring <b>76</b> is formed over shield ring <b>74</b>′ and edge ring <b>58</b>′ serving as the peripheral ring, the temperature of cover ring <b>76</b> is slightly lower than those of shield ring <b>74</b>′ and edge ring <b>58</b>′, and is lower than that of semiconductor wafer W by 20° C. to 30° C., for example, about 170° C. That is, the surface temperature of the peripheral edge of mounting platform <b>28</b> is maintained at a temperature near that of semiconductor wafer W, that is, equal to or lower than that of semiconductor wafer W which is the workpiece. The decomposition temperature of Ru₃(CO)₁₂is 130° C. or more, and cover ring <b>76</b> is heated to a temperature equal to or higher than the decomposition temperature of the source gas.

0113In the third embodiment, as illustrated in <figref idref="DRAWINGS">FIG. 13</figref>, since orifice <b>118</b> of which flow path area is appropriately made narrower is installed as in the second embodiment, the source gas flows as illustrated in <figref idref="DRAWINGS">FIG. 10</figref> and stays within processing space S for a suitable time, and further, the amount of source gas residing in the central portion of processing space S does not become excessive, and the atmosphere in processing space S is discharged through orifice <b>118</b> of gas outlet <b>92</b>. That is, the concentration of the source gas residing in the central portion of processing space S always maintained to be lower than that residing in the periphery thereof, and the source gas contained in processing space S is allowed to stay appropriately while maintaining such concentration conditions as described above. As a result, it is possible to deposit Ru film at a high deposition rate while maintaining a high in-plane uniformity of the film thickness.

0114Furthermore, shield ring <b>74</b>′ and edge ring <b>58</b>′ constituting the peripheral ring of the peripheral edge of mounting platform <b>28</b> is set to a temperature (180° C. to 190° C.) equal to or slightly lower than the temperature (190° C.) of semiconductor wafer W and also the temperature of the purge gas being flown is maintained at a temperature near that of semiconductor wafer W. Therefore, the temperature of the peripheral edge of semiconductor wafer W on mounting platform <b>28</b> is maintained at a relatively high, so that it is possible to make in-plane uniformity of the film thickness to be higher than that in the second embodiment.

0115In the related art, the source gas passes through the peripheral edge of the mounting platform to be discharged, and further the peripheral edge of the mounting platform is heated to a temperature (e.g., 215° C.) equal to that of the central portion on which semiconductor wafer W is mounted, so that the source gas is decomposed at the peripheral edge of the mounting platform to cause a large amount of films to be deposited thereon. However, in the third embodiment, the end portions of edge ring <b>58</b>′ and shield ring <b>76</b> are covered by orifice forming member <b>116</b> being maintained at a temperature, for example, about 80° C., lower than the decomposition temperature of the source gas. Further, shield ring <b>74</b>′ and edge ring <b>58</b>′ of mounting platform <b>28</b> are formed to be partially contacted with mounting platform main body <b>50</b> to allow the temperatures of the edge of shield ring <b>74</b>′ and edge ring <b>58</b>′ to be a temperature (180° C. to 190° C.) which is lower than that of the mounting platform main body <b>50</b> and equal to or slightly lower than that of semiconductor wafer W. Therefore, the temperature of cover ring <b>76</b> located above semiconductor wafer W can be reduced further (e.g., 170° C.). As a result, it is possible to suppress the deposition of the film on the peripheral edge of mounting platform <b>28</b>.

0116Furthermore, since a purge gas flows from a gap <b>122</b> between inner peripheral ring <b>76</b>A and outer peripheral ring <b>76</b>B to a gap <b>92</b>B between orifice forming member <b>116</b> and the surfaces of shield ring <b>74</b>, cover ring <b>76</b> and edge ring <b>58</b> corresponding to the peripheral edge of mounting platform <b>28</b>, an unnecessary deposition of the film on those surfaces can be further suppressed. In this case, since the temperature of the purge gas is about 170° C., even when the flow rate is somewhat increased, the variation of the film thickness can be maintained at a low degree. Accordingly, it is possible to effectively prevent the unnecessary deposition of film by increasing the flow rate of the purge gas.

0117In addition, since the outer peripheral side of edge ring <b>58</b>′ is covered by over member <b>164</b> maintained at a temperature of, for example, about 80° C., which is lower than that of the source gas, the deposition of film on the covered outer peripheral side is also suppressed.

0118As described above, in the third embodiment, in addition to further improve the in-plane uniformity of the film thickness, an unnecessary deposition of film on the peripheral edge of mounting platform <b>28</b> can be suppressed. Further, since the unnecessary adhesion of film on the peripheral edge of mounting platform <b>28</b> can be suppressed, it is possible to discharge the source gas that does not contribute to the reaction on semiconductor wafer W at a high ratio in a non-reacted state. Therefore, it is possible to recover the expensive source gas of Ru₃(CO)₁₂in a high recovery rate.

0119In case of depositing the Ru film, the temperature of semiconductor wafer W is preferably 150° C. to 250° C., and the temperature of orifice forming member <b>116</b> and cover member <b>164</b> is preferably has a temperature of 50° C. to 120° C. at which the raw material is not decomposed, solidified and liquefied. Also the temperature of cover ring <b>76</b> is preferably lower than that of semiconductor wafer W by 20° C. to 30° C.

Evaluation of Experiment of Third Embodiment

Relationship Between the Semiconductor Wafer Temperature and the Deposition Rate

0120In the third embodiment, results obtained from the investigation of the relationship between the temperature of the wafer and the deposition rate when Ru₃(CO)₁₂is actually used as the raw material will be described. <figref idref="DRAWINGS">FIG. 14</figref> is a graph illustrating a relationship between the temperature of the wafer and the deposition rate when Ru₃(CO)₁₂is used as the raw material. Herein, CO gas is used as the carrier gas and the flow rate of the CO gas is set to 100 sccm. As illustrated in <figref idref="DRAWINGS">FIG. 14</figref>, the film is not deposited when the wafer temperature is lower than 140° C., and the film deposition starts when the wafer temperature is about 140° C. The deposition rate increases rapidly with increasing the temperature. It may be understood that the wafer temperature of 175° C. or more is required for obtaining the deposition rate of 1 nm/min or more, and the wafer temperature of 190° C. or more is required for obtaining the deposition rate of 2 nm/min or more.

Relationship Between Temperature of Shield Ring as a Peripheral Component of Main Body of Mounting Platform and in-Plane Uniformity of Film Thickness

0121Next, the results obtained from the investigation of the relationship between the temperature of the shield ring of a peripheral component of the mounting platform main body and the in-plane uniformity of the film thickness will be described. <figref idref="DRAWINGS">FIG. 15</figref> is a graph illustrating a relationship between the temperature of the shield ring <b>74</b>′ as a peripheral component and the in-plane uniformity of the film thickness. Herein, CO gas is used as the carrier gas, the flow rate of the CO gas is set to 100 sccm and the temperature of wafer is set to 190° C. As illustrated in <figref idref="DRAWINGS">FIG. 15</figref>, it may be understood that the in-plane uniformity of the film thickness deposited on the surface of the wafer tends to be bad when the temperature of the shield ring <b>74</b>′ is low, but the in-plane uniformity of the film thickness is improved with increasing the temperature of the shield ring. When the temperature of the shield ring is about 180° C., the in-plane uniformity of the film thickness is improved up to about 6%, and after that, even when the temperature of the shield ring is increased further, the in-plane uniformity of the film thickness is nearly saturated to be maintained at about 6%. Accordingly, it may be understood that shield ring <b>74</b>′ nearest to mounting platform main body <b>50</b> is preferably set to 180° C. or more.

Relationship Between Flow Rate of Purge Gas and in-Plane Uniformity of Film Thickness

0122Next, the resultant film thickness and the in-plane uniformity of film thickness (1σ [%]) of the Ru film obtained when depositing a film while varying the flow rate of the purge gas using the deposition device of the third embodiment will be described with reference to <figref idref="DRAWINGS">FIG. 16</figref>. As illustrated in <figref idref="DRAWINGS">FIG. 16</figref>, it may be understood even when increasing the flow rate of the purge gas up to 100 sccm, the film thickness and the in-plane uniformity of the film thickness of the Ru film is not affected by the flow rate of the purge gas, so that it is possible to enhance the effect of preventing the unnecessary deposition of film.

Relationship Between Recovery Rate of Raw Material and in-Plane Uniformity of Film Thickness in a Case where the Temperature of the Peripheral Components is Controlled

0123Next, the results obtained from the investigation of the relationship between the recovery rate of raw material and the in-plane uniformity of film thickness in a case where the temperature of cover ring <b>76</b> as the peripheral component is varied will be described. <figref idref="DRAWINGS">FIG. 17</figref> is a graph illustrating a relationship between a recovery rate of raw material and the in-plane uniformity of film thickness in a case where the temperature of cover ring <b>76</b> as a peripheral component of the mounting platform main body is varied. The wafer temperature was set to 190° C. in each experiment. The temperature of cover ring <b>76</b> is set to 170° C. in the experiment <b>1</b> which corresponds to the deposition method of the third embodiment, set to 190° C. which is the same temperature as the wafer temperature in experiment <b>2</b>, and set to 80° C. in experiment <b>3</b>. The respective temperatures of orifice forming member <b>116</b>, internal partition wall <b>90</b> and cover member <b>164</b> are set to 80° C. in each of experiments <b>1</b>, <b>2</b> and <b>3</b>.

0124In the graph shown in <figref idref="DRAWINGS">FIG. 17</figref>, the left longitudinal axis and the right longitudinal axis represent the recovery rate of the raw material and in-plane uniformity of the film thickness, respectively. In experiment <b>1</b> corresponding to the deposition device of the third embodiment, the graph shows that the recovery rate of the raw material reaches up to 60% and the in-plane uniformity of the film thickness is about 6%, and thus, both values represent the good results. In contrast, in experiment <b>2</b> where the temperature of cover ring <b>76</b> is set to 190° C. which is the same as the temperature of the wafer, the in-plane uniformity of the film thickness is equivalent to that obtained in experiment <b>1</b>, but, the recovery rate of the raw material has become a smaller value. In experiment <b>3</b> where the temperature of cover ring <b>76</b> is set to 80° C., it has been confirmed that the recovery rate of the raw material is almost the same as that in experiment <b>1</b>, but the in-plane uniformity of the film thickness is deteriorated.

0125Recovery rate of the raw material under various conditions

0126Next, the recovery rate of raw material in the deposition device under various conditions was investigated. <figref idref="DRAWINGS">FIG. 18</figref> is a graph illustrating the results obtained from confirmation of adhesion of the source gas with respect to the deposition device of Patent Document 3 and the deposition device according to the third embodiment, and two deposition devices corresponding to an intermediate level of the deposition devices of Patent Document 3 and the deposition device of the third embodiment. Herein, it is assumed that the temperatures of shield ring <b>74</b>′ and edge ring <b>58</b>′ of the mounting platform is to be increased to about 180° C. to about 190° C., the temperature of cover ring <b>76</b> is to be increased to 170° C. in advance, and the reference numeral A denotes the deposition device of Patent Document 3 in which orifice forming member <b>116</b> and cover member <b>164</b> are not installed and the purge gas is absent, the reference numeral B denotes the deposition device embodiment in which orifice forming member <b>116</b> is installed, the purge gas is absent and cover member <b>164</b> is not installed, the reference numeral C denotes the deposition device embodiment in which orifice forming member <b>116</b> is installed, the purge gas is present and cover member <b>164</b> is not installed, and the reference numeral D denotes the deposition device of the third embodiment.

0127As illustrated in <figref idref="DRAWINGS">FIG. 18</figref>, the following matters have been confirmed. In the deposition device of Patent Document 3, most of the source gas which did not contribute to the deposition of film on semiconductor wafer W was consumed for depositing the film on cover ring <b>76</b>, so that the non-reacted source gas can be hardly recovered. In contrast, in the deposition device B in which orifice forming member <b>116</b> was installed, the amount of the source gas consumed for depositing of film on cover ring <b>76</b> was significantly reduced to increase the amount of the non-reacted source gas up to 30.7%. In the meantime, in the deposition device C in which the purge gas was introduced, the amount of the source gas consumed for depositing on shield ring <b>74</b>′ is reduced to increase the amount of the non-reacted source gas up to 32.0%. Further, in the deposition device of the third embodiment in which cover member <b>164</b> was installed, the deposition of the film on a rear surface of edge ring <b>58</b>′ was significantly reduced to increase the amount of the non-reacted source gas up to 65.8%.

0128As described above, according to the third embodiment, a high deposition rate and a further improved in-plane uniformity of the film thickness can be obtained and the deposition of the unnecessary film on the peripheral edge of mounting platform <b>28</b> can be suppressed to be smaller as well, so that the non-reacted source gas can be effectively recovered.

0129Further, in the first and the second embodiments, the temperature of the peripheral edge of mounting platform <b>28</b> is maintained at 80° C. at which a deposition reaction does not occur, so that it is possible to suppress the deposition of the unnecessary film and improve the recovery rate of the source gas.

Deposition Device According to Fourth Embodiment

0130Next, the deposition device according to a fourth embodiment of the present invention will be described. <figref idref="DRAWINGS">FIG. 19</figref> is a partially enlarged cross-sectional view illustrating a portion of the deposition device according to the fourth embodiment of the present invention. The fourth embodiment is configured with a combination of the first embodiment and the third embodiment, and the same reference numerals are given to the same elements and the description thereof will be simplified.

0131In the fourth embodiment, orifice forming member <b>96</b> made of the same material as the material of internal partition wall <b>90</b> is integrally formed with internal partition wall <b>90</b> at the lower end portion of orifice forming member <b>96</b> as in the first embodiment, and orifice <b>98</b> is formed between below orifice forming member <b>96</b> and the top surface of cover ring member <b>76</b> and forms gas outlet <b>92</b>. Further, in the third embodiment, cover ring <b>76</b> is divided into inner peripheral ring <b>76</b>A and outer peripheral ring <b>76</b>B. However, in this embodiment, cover ring <b>76</b> is formed integrally as in the first embodiment, and the purge gas supply mechanism supplying the purge gas is not installed. Shield ring <b>74</b>′ and edge ring <b>58</b>′ are configured to be the same as those of the third embodiment, and the temperature settings are the same as those of the third embodiment.

0132Also in the fourth embodiment, as in the first embodiment, a portion of the source gas flowing-down toward an area outer side of outer peripheral end of wafer W corresponding to the periphery of mounting platform <b>28</b> travels and diffuses toward the central portion of processing space S in the middle of the flowing-down to stay there. Simultaneously, most of the source gas having been flowed-down comes in contact with orifice forming member <b>96</b> installed to be extended toward the central portion of processing space S at the lower end of internal partition wall <b>90</b>, and deflects toward the central portion of processing space S. A portion of the source gas having been deflected stays in processing space S, while most of the source gas flows into orifice <b>98</b> of which the flow path area is made narrower and passes through gas outlet <b>92</b> to flow into a space formed at below mounting platform <b>28</b> in processing container <b>22</b> as indicated by the arrow <b>115</b>. Further, as in the third embodiment, since the temperature of cover ring <b>76</b> is set to be slightly lower than the wafer temperature, the deposition of the film thereon is suppressed. Also, the deposition of the film on the outside of edge ring <b>58</b>′ is prevented by cover member <b>164</b> having a temperature of about 80° C. which is lower than the decomposition temperature of the source gas. Therefore, it is possible to increase the recovery rate of the raw material used for deposition by increasing the ratio of the source gas discharged with a non-reacted state.

0133Various modifications of the present invention may be made without being limited to the embodiments described above. For instance, in the embodiments described above, description is made regarding formation of the Ru film using, for example, Ru₃(CO)₁₂as an organometallic compound. However, the present invention may use one of materials among W(CO)₆, Ni(CO)₄, Mo(CO)₆, Co₂(CO)₈, Rh₄(CO)₁₂, Re₂(CO)₁₀, Cr(CO)₆, Os₃(CO)₁₂, Ta(CO)₅, tetrakisethylmethylaminotitanium (TEMAT), TAIMATA, Cu(EDMDD)₂, TaCl₅, Trimethylaluminium(TMA), tert-butylimido tris(diethylamido)tantalum (TBTDET), PentaEthoxyTantalum (PET), Tetramethylsilane (TMS), tetrakisethoxyhafnium (TEH), Cp₂Mn[=Mn(C₅H₅)₂], (MeCp)₂Mn[=Mn(CH₃C₅H₄)₂], (EtCp)₂Mn[=Mn(C₂H₅C₅H₄)₂], (i-PrCp)₂Mn[=Mn(C₃H₇C₅H₄)2], MeCpMn(CO)₃[=CH₃C₅H₄)Mn(CO)₃], (t-BuCp)₂Mn[=Mn(C₄H₉C₅H₄)₂], CH₃Mn(CO)₅, Mn(DPM)₃[=Mn(C₁₁H₁₉O₂)₃], Mn(DMPD)(EtCp)[=Mn(C₇H₁₁C₂H₅C₅H₄)], Mn(acac)₂[=Mn(C₅H₇O₂)₂], Mn(DPM)₂[=Mn(C₁₁H₁₉O₂)₂], Mn(acac)₃[=Mn(C₅H₇O₂)₃], without being limited to the Ru₃(CO)₁₂.

0134In the above-described description, a semiconductor wafer is exemplified as a workpiece, but the semiconductor wafer includes GaAs, SiC and GaN compound semiconductor substrates in addition to Si semiconductor substrate. Further, the present invention may be applied to, for example, a glass substrate or a ceramic substrate used in a liquid crystal display apparatus, in addition to the semiconductor wafer.