Ion assisted deposition for rare-earth oxide based coatings

Embodiments of the present invention generally relate to chamber lids and chamber nozzles having a thin, plasma resistant protective layer.

background

In the semiconductor industry, devices are manufactured by many manufacturing processes that create structures of ever-decreasing size. Some manufacturing processes (eg, plasma etching and plasma cleaning processes) expose the substrate to a high speed stream of plasma to etch or clean the substrate. The plasma can be very erosive and can erode the processing chamber and other surfaces exposed to the plasma.

The lid and nozzle are two important etching chamber components in conductor and dielectric etching. Usually the lid and nozzle are made of bulk ceramics. However, with the continuous decline of device nodes, stringent defect requirements are dictated. Some of these new applications use high operating temperatures (eg, above about 300 ° C). When used in such high temperature applications, many bulk ceramics may crack due to thermal impact. Also, plasma resistant bulk ceramics are generally very expensive.

Al₂O₃Is Al₂O₃Due to its high thermal conductivity and bending strength, it can be used for lids and nozzles. However, under fluorochemistry, exposed Al₂O₃Form AlF particles as well as Al metal contamination on the treated wafer. Recent efforts have been to coat the plasma facing surfaces of the lid and nozzle with a thick protective coating. Thick film coatings (eg, plasma spray coatings) are being studied to reduce metal contamination on wafers. However, in some examples, the vacuum seal of the plasma spray coating is a concern because the plasma spray coating does not maintain a vacuum due to the inherent pores and cracks. Also, plasma spray coatings have long lead times and are typically preceded by special surface treatments that ultimately increase costs. Also, regenerating (refurbishing) the coating can be a challenge due to surface preparation and cost.

A thin film coating technique known as physical deposition (PVD) is being investigated for coating lids and nozzles. However, the PVD coating process is very slow (affecting the final cost of coating), so a coating thick enough to meet the life requirements of the component (especially for non-consumable parts such as lids and nozzles). It may not be generated. Also, PVD coatings typically have high residual stresses that reduce component life due to coating cracking and peeling in some cases.

The present invention is shown in the figures of the accompanying drawings as an example, not as a limitation, with similar reference numerals indicating similar elements. It should be noted that different references to "one" or "one" embodiment in this disclosure are not necessarily references to the same embodiment, and such references mean at least one.<figref num="1">A cross-sectional view of an embodiment of a processing chamber is shown.</figref><figref num="2A">We show a deposition mechanism applicable to various deposition techniques using high energy particles such as ion-assisted deposition (IAD).</figref><figref num="2B">The schematic diagram of the IAD deposition apparatus is shown.</figref><figref num="3">~</figref><figref num="4">A cross-sectional side view of an article (eg, a lid and / or a nozzle) covered with one or more thin film protective layers is shown.</figref><figref num="5A">A perspective view of a chamber lid having a plasma resistant layer of rare earth oxide according to an embodiment is shown.</figref><figref num="5B">A cross-sectional side view of a chamber lid having a plasma resistant layer of rare earth oxide according to an embodiment is shown.</figref><figref num="5C">A perspective view of a chamber nozzle having a plasma resistant layer of rare earth oxide according to an embodiment is shown.</figref><figref num="6">An embodiment of the process for forming one or more protective layers on a lid or nozzle is shown.</figref><figref num="7">Dielectric-etched CF, including the erosion rates of a plurality of different IAD coatings produced according to the embodiments described herein.₄Shows the erosion rate of various materials exposed to chemicals.</figref><figref num="8">~</figref><figref num="9">CH for the thin film protective layer formed according to the embodiment of the present invention, respectively.₄-Cl₂And CHF₃-NF₃-Cl₂Shows the erosion rate under chemical substances.</figref><figref num="10">~</figref><figref num="11">CH4-Cl2 and CHF for the thin film protective layer formed according to the embodiment of the present invention, respectively.₃-NF₃-Cl₂Shows the roughness profile under the chemicals of.</figref><figref num="12">CF with low bias₄-CHF₃Shows the erosion rate of various materials exposed to trench chemistry.</figref>

Detailed description of embodiments

Embodiments of the invention provide articles for etching reactors (eg, lids and / or nozzles) having a thin film protective layer on one or more plasma facing surfaces of the article. The protective layer can have a thickness of up to about 300 μm and can provide plasma corrosion resistance to protect the article. The protective layer can be formed on the article using ion-assisted vapor deposition (IAD) (eg, using the electron beam IAD (EB-IAD)). The thin protective layer is Y₃Al₅O₁₂, Y₄Al₂O₉, Er₂O₃, Gd₂O₃, Er₃Al₅O₁₂, Gd₃Al₅O₁₂, Y₄Al₂O₉And Y₂O₃-ZrO₂It can be a ceramic compound containing a solid solution of the above, or another rare earth oxide. The improved corrosion resistance provided by the thin protective layer can improve the useful life of the article while reducing maintenance and manufacturing costs. Also, the IAD coating can be applied thick enough to provide a longer life for the lid and / or nozzle and can have a good airtight seal to maintain vacuum. The IAD coating is applied and can later be regenerated at low cost.

FIG. 1 is a cross-sectional view of a semiconductor processing chamber 100 having one or more chamber components coated with a thin film protective layer according to an embodiment of the present invention. The processing chamber 100 can be used for processes that provide a corrosive plasma environment inside. For example, the processing chamber 100 can be a chamber for a plasma etching reactor (also known as a plasma etching apparatus), a plasma washer, and the like. Examples of chamber components that can include a thin protective layer are substrate support assembly 148, electrostatic chuck (ESC) 150, ring (eg process kit ring or single ring), chamber wall, base, gas distribution plate, shower. Includes head, liner, liner kit, shield, plasma screen, flow equalizer, cooling base, chamber view port, chamber lid 104, nozzle and more. In one particular embodiment, the protective layer is applied on the chamber lid 104 and / or the chamber nozzle 132.

The thin film protective layer described in more detail below is a rare earth oxide layer deposited by ion-assisted deposition (IAD). The thin protective layer is Y₂O₃And Y₂O₃System ceramics, Y₃Al₅O₁₂(YAG), Y₄Al₂O₉(YAM), Er₂O₃And Er₂O₃System ceramics, Gd₂O₃And Gd₂O₃System ceramics, Er₃Al₅O₁₂(EAG), Gd₃Al₅O₁₂(GAG), Nd₂O₃And Nd₂O₃System ceramics, YAlO₃(YAP), Er₄Al₂O₉(EAM), ErAlO₃(EAP), Gd₄Al₂O₉(GdAM), GdAlO₃(GdAP), Nd₃Al₅O₁₂(NdAG), Nd₄Al₂O₉(NdAM), NdAlO₃(NdAP) and / or Y₄Al₂O₉And Y₂O₃-ZrO₂It can contain a ceramic compound containing a solid solution of the above. Thin protective layer is YF₃, Er-Y composition (eg 80% by weight Er, and 20% by weight Y), Er-Al-Y composition (eg 70% by weight Er, 10% by weight Al, and 20% by weight Y) %), Er-Y-Zr-based compositions (eg, 70% by weight Er, 20% by weight Y, and 10% by weight Zr), or Er-Al compositions (eg, 80% by weight Er), and Al can also contain 20% by weight).

The thin film protective layer can also be based on a solid solution formed by any of the above ceramics. Y₄Al₂O₉And Y₂O₃-ZrO₂With reference to a ceramic compound containing a solid solution of, in one embodiment, the ceramic compound is Y in a 62.93 molar ratio (mol%).₂O₃And 23.23 mol% ZrO₂And 13.94 mol% Al₂O₃including. In another embodiment, the ceramic compound is Y in the range of 50-75 mol%.₂O₃And ZrO in the range of 10-30 mol%₂And Al in the range of 10-30 mol%₂O₃Can be included. In another embodiment, the ceramic compound is Y in the range of 40-100 mol%.₂O₃And ZrO in the range of 0-60 mol%₂And Al in the range of 0-10 mol%₂O₃Can be included. In another embodiment, the ceramic compound is Y in the range of 40-60 mol%.₂O₃And ZrO in the range of 30-50 mol%₂And Al in the range of 10 to 20 mol%₂O₃Can be included. In another embodiment, the ceramic compound is Y in the range of 40-50 mol%.₂O₃And ZrO in the range of 20-40 mol%₂And Al in the range of 20-40 mol%₂O₃Can be included. In another embodiment, the ceramic compound is Y in the range of 70-90 mol%.₂O₃And ZrO in the range of 0-20 mol%₂And Al in the range of 10 to 20 mol%₂O₃Can be included. In another embodiment, the ceramic compound is Y in the range of 60-80 mol%.₂O₃And ZrO in the range of 0-10 mol%₂And Al in the range of 20-40 mol%₂O₃Can be included. In another embodiment, the ceramic compound is Y in the range of 40-60 mol%.₂O₃And ZrO in the range of 0-20 mol%₂And Al in the range of 30-40 mol%₂O₃Can be included. In other embodiments, other allocations can also be used for ceramic compounds.

In one embodiment, Y₂O₃, ZrO₂, Er₂O₃, Gd₂O₃, And SiO₂Alternative ceramic compounds containing the combination of are used for the protective layer. In one embodiment, the alternative ceramic compound is Y in the range of 40-45 mol%.₂O₃And ZrO in the range of 0-10 mol%₂And Er in the range of 35-40 mol%₂O₃And Gd in the range of 5-10 mol%₂O₃And SiO in the range of 5 to 15 mol%₂Can be included. In the first embodiment, the alternative ceramic compound is 40 mol% Y₂O₃, 5 mol% ZrO₂, 35 mol% Er₂O₃, 5 mol% Gd₂O₃, And 15 mol% SiO₂including. In the second embodiment, the alternative ceramic compound is 45 mol% Y₂O₃, 5 mol% ZrO₂, 35 mol% Er₂O₃, 10 mol% Gd₂O₃, And 5 mol% SiO₂including. In the third embodiment, the alternative ceramic compound is 40 mol% Y₂O₃, 5 mol% ZrO₂, 40 mol% Er₂O₃, 7 mol% Gd₂O₃, And 8 mol% SiO₂including.

Each of the above thin film protective layers is made of a trace amount of other material (for example, ZrO).₂, Al₂O₃, SiO₂, B₂O₃, Er₂O₃, Nd₂O₃, Nb₂O₅, CeO₂, Sm₂O₃, Yb₂O₃, Or other oxides).

The thin film protective layer can be an IAD coating applied on different ceramics including oxide-based ceramics, nitride-based ceramics, and carbide-based ceramics. An example of oxide-based ceramics is SiO₂(Quarter), Al₂O₃, Y₂O₃And so on. Examples of carbide-based ceramics include SiC, SiC-SiC and the like. Examples of nitride-based ceramics include AlN, SiN, and the like. The IAD coating target material can be a calcined powder, a preformed mass (eg, formed by a green press, hot press, etc.), a sintered body (eg, having a density of 50-100%), or (eg, a density of 50-100%). , Ceramics, metal, or metal alloy).

As shown, the lid 130 and the nozzle 132 each have the thin film protective layers 133, 134 according to one embodiment. However, it should be understood that any of the other chamber components (eg, those listed above) can also include a thin film protective layer.

In one embodiment, the processing chamber 100 includes a chamber body 102 and a lid 130 that surround an internal volume 106. The lid 130 has a hole in its center and the nozzle 132 can be inserted into the hole. The chamber body 102 can be made from aluminum, stainless steel, or other suitable material. The chamber body 102 generally includes a side wall 108 and a bottom 110. Any of the lid 130, the nozzle 132, the side wall 108, and / or the bottom 110 can include a thin film protective layer.

The outer liner 116 can be placed adjacent to the side wall 108 to protect the chamber body 102. The outer liner 116 can be manufactured and / or coated with a thin film protective layer. In one embodiment, the outer liner 116 is made from aluminum oxide.

The exhaust port 126 can be formed within the chamber body 102 and the internal volume 106 can be coupled to the pump system 128. The pump system 128 can include one or more pumps and throttle valves that are used to evacuate and regulate the pressure of the internal volume 106 of the processing chamber 100.

The lid 130 can be supported on the side wall 108 of the chamber body 102. The lid 130 can be opened to allow access to the internal volume 106 of the processing chamber 100 and can provide a seal to the processing chamber 100 upon closing. The gas panel 158 is coupled to the processing chamber 100, which allows the processing gas and / or cleaning gas to be provided to the internal volume 106 through the nozzle 132. The lid 130 is made of ceramics (eg, Al).₂O₃, Y₂O₃, YAG, SiO₂, AlN, SiN, SiC, SiC-SiC, or Y₄Al₂O₉And Y₂O₃-ZrO₂It can be a ceramic compound containing a solid solution of. The nozzle 132 can also be ceramics (eg, any of these ceramics listed for the lid). The lid 130 and / or the nozzle 132 can be coated with the thin film protective layers 133 and 134, respectively.

Examples of treatment gases that can be used to process substrates within the processing chamber 100 are halogen-containing gases (eg, among other things, C).₂F₆,SCIENCE FICTION₆, SiCl₄, HBr, NF₃, CF₄, CHF₃, CH₂F₃, F, NF₃, Cl₂, CCl₄, BCl₃, And SiF₄) And other gases (eg O₂, Or N₂O) is included. An example of a carrier gas is N₂, He, Ar, and other gases that are inert to the processing gas (eg, non-reactive gases). The substrate support assembly 148 is located within the internal volume 106 of the processing chamber 100 under the lid 130. The board support assembly 148 holds the board 144 during processing. Ring 146 (eg, a single ring) can cover a portion of the electrostatic chuck 150 and protect the covered portion during processing from exposure to plasma. The ring 146 can, in one embodiment, be silicon or quartz.

The inner liner 118 may be coated on the periphery of the substrate support assembly 148. The inner liner 118 can be a halogen-containing gas resist material (eg, as described with reference to the outer liner 116). In one embodiment, the inner liner 118 can be manufactured from the same material as the outer liner 116. Further, the inner liner 118 can be coated with a thin film protective layer.

In one embodiment, the substrate support assembly 148 includes a mounting plate 162 that supports the pedestal 152 and an electrostatic chuck 150. The electrostatic chuck 150 further includes a thermally conductive base 164 and an electrostatic pack 166 bonded to the thermally conductive base by an adhesive 138 (which in one embodiment may be a silicone adhesive). The mounting plate 162 is coupled to the bottom 110 of the chamber body 102 and includes a passage for routing utilities (eg, fluids, power lines, sensor leads, etc.) to the thermoconductive base 164 and the electrostatic pack 166.

The thermally conductive base 164 and / or the electrostatic pack 166 includes one or more optional embedded heating elements 176, embedded thermal insulators 174, and / or conduits 168, 170, thereby the supporting assembly 148. The lateral temperature profile can be controlled. The conduits 168, 170 can be fluid coupled to a fluid source 172 that circulates the temperature controlled fluid through the conduits 168, 170. The embedded thermal insulator 174 can, in one embodiment, be placed between the conduits 168, 170. The heater 176 is adjusted by the heater power supply 178. The conduits 168,170 and the heater 176 are utilized to control the temperature of the thermally conductive base 164, whereby the electrostatic pack 166 and the substrate to be processed (eg, wafer) can be heated and / or cooled. The temperature of the electrostatic pack 166 and the heat conductive base 164 can be monitored using a plurality of temperature sensors 190, 192 that can be monitored using the controller 195.

The electrostatic pack 166 can further include a plurality of gas passages (eg, grooves, mess, and other surface structures that can be formed within the top surface of the pack 166). The gas passage can be fluid coupled to a source of heat transfer (or backside) gas (eg, He) through a hole drilled in the pack 166. During operation, the backside gas is supplied into the gas passage at a controlled pressure, which can improve heat transfer between the electrostatic pack 166 and the substrate 144.

The electrostatic pack 166 includes at least one clamping electrode 180 controlled by a chucking power supply 182. Electrodes 180 (or other electrodes located within pack 166 or base 164) are routed through matching circuit 188 to maintain plasma formed from the processing gas and / or other gas within the processing chamber 1001 It can be further coupled to the above RF power supplies 184 and 186. Power supplies 184, 186 can generally generate RF signals with frequencies from about 50 kHz to about 3 GHz and powers up to about 10,000 watts.

Figure 2A shows a deposition mechanism applicable to various deposition techniques utilizing high energy particles such as ion-assisted deposition (IAD). Typical IAD methods are deposition processes incorporating ionic impacts (eg, activating reactive deposition (ARE)) and sputtering in the presence of ionic impacts, as described herein. ) Is included, thereby forming a plasma resistant coating. One particular type of IAD performed in the embodiment is the electron beam IAD (EB-IAD). Both IAD methods are reactive gas species (eg, O)₂, N₂, Halogen, etc.). Such reactive species can burn surface organic contaminants before and / or during deposition. Also, the IAD deposition process for ceramics target deposition as opposed to metal target deposition is O in the embodiment.₂It can be controlled by the partial pressure of ions. For example, Y₂O₃The coating is done by the evaporation of the Y metal and the outflow of oxygen ions, which allows the formation of oxides of the yttrium material on the surface of the component. Alternatively, the ceramics target can be used without oxygen or with low oxygen.

As shown, the thin film protective layer 215 is formed on the article 210 or on a plurality of articles 210A, 210B by the accumulation of the deposited material 202 in the presence of high energy particles 203 such as ions. The deposit material 202 can include atoms, ions, radicals and the like. The high energy particles 203 can collide with and compress the thin film protective layer 215 when the thin film protective layer 215 is formed.

In one embodiment, EB IAD is utilized to form the thin film protective layer 215. FIG. 2B shows a schematic diagram of the IAD depositor. As shown, the material source 250 provides the flux of the deposited material 202, while the high energy particle source 255 provides the flux of the high energy particles 203, both of which through the IAD process, article 210, Collide with 210A and 210B. The high energy particle source 255 can be an oxygen or other ion source. The high energy particle source 255 is also derived from other types of high energy particles (eg, inert radicals, neutron atoms) from the source of the particle (eg, from a plasma, reactive gas, or material source that provides a deposit material). , And nano-sized particles).

The material source (eg, target body) 250 used to provide the deposited material 202 can be bulk sintered ceramics corresponding to the same ceramics constituting the thin film protective layer 215. For example, the material source is bulk sintered ceramic composite, or bulk sintered YAG, Er.₂O₃, Gd₂O₃, Er₃Al₅O₁₂, Or Gd₃Al₅O₁₂, Or other ceramics described above. Other target materials (eg, powder, baked powder, preformed (eg, formed by green press or hot press), or machined material (eg, molten material) can also be used. All of the different types of material source 250 are melted into the molten material source during deposition. However, different types of starting material take different amounts of time to melt. The molten material and / or machined product The preformed material melts slower than the molten material, the roasted powder melts slower than the preformed material, and the standard powder melts slower than the roasted powder.

The IAD can utilize one or more plasmas or beams (eg, electron beams) to provide materials and high energy ion sources. Reactive species can also be supplied during the deposition of plasma resistant coatings. In one embodiment, the high energy particle 203 comprises at least one of a non-reactive species (eg, Ar) or a reactive species (eg, O). In a further embodiment, reactive species (eg, CO) and halogens (Cl, F, Br, etc.) are also introduced during the formation of the plasma resistant coating, thereby the deposit material most weakly bound to the thin film protective layer 215. Can be further increased in the tendency to selectively remove.

The IAD process allows the high energy particle 203 to be controlled by the high energy ion (or other particle) source 255 independently of other deposition parameters. Depending on the energy (eg, velocity), the density and angle of incidence of the high energy ion flux, the composition, structure, crystal orientation and particle size of the thin film protective layer can be manipulated.

Additional adjustable parameters are the temperature of the article during deposition, as well as the duration of deposition. In one embodiment, the IAD deposition chamber (and the chamber lid or nozzle therein) is heated to a starting temperature of 160 ° C. or higher prior to deposition. In one embodiment, the starting temperature is 160 ° C to 500 ° C. In one embodiment, the starting temperature is 200 ° C to 270 ° C. The chamber temperature and lid or nozzle temperature can then be maintained at the starting temperature during deposition. In one embodiment, the IAD chamber comprises a heating lamp for heating. In an alternative embodiment, the IAD chamber and lid or nozzle are not heated. If the chamber is not heated, it naturally rises to about 160 ° C as a result of the IAD process. Higher temperatures during deposition can increase the density of the protective layer, but can also increase the mechanical stress of the protective layer. Active cooling can be added to the chamber to maintain a low temperature during coating. In one embodiment, the low temperature can be maintained at any temperature below 160 ° C and up to a minimum of 0 ° C.

Additional parameters that can be adjusted are working distance 270 and incident angle 272. The working distance 270 is the distance between the material source 250 and the articles 210A, 210B. In one embodiment, the working distance is 0.2-2.0 meters, and in one particular embodiment, the working distance is 1.0 meters. Decreasing the working distance increases the deposition rate and increases the effectiveness of ionic energy. However, reducing the working distance below a certain point can reduce the uniformity of the protective layer. The angle of incidence is the angle at which the deposited material 202 collides with articles 210A and 210B. In one embodiment, the angle of incidence is 10-90 degrees, and in one particular embodiment, the angle of incidence is about 30 degrees.

The IAD coating can be applied over a wide range of surface conditions with roughness from about 0.5 microinch (μin) to about 180 μin. However, a smoother surface facilitates coating with a uniform coating. The coating thickness can be up to about 300 microns (μm). At the time of manufacture, the thickness of the coating on the component is intentionally at the bottom of the coating layer stack with a rare earth oxide-based colorant (eg, Nd).₂O₃, Sm₂O₃, Er₂O₃Etc.) can be added. The thickness can also be accurately measured using polarization analysis.

The IAD coating can be amorphous or crystalline, depending on the rare earth oxide composite material used to make the coating. For example, EAG and YAG are amorphous coatings, while Er₂O₃And Y₄Al₂O₉And Y₂O₃-ZrO₂Ceramic compounds containing the solid solution of are typically crystalline. Amorphous coatings are more compatible (conformal) and reduce lattice mismatch-induced epitaxial cracks, while crystalline coatings are more corrosion resistant.

The coating structure can be a two-layer or multi-layer structure. In a two-layer structure, an amorphous layer can be deposited as a buffer layer to minimize epitaxial cracks, followed by a crystalline layer that can be corrosion resistant at the top. In a multi-layer design, the layer material can be used to create a smooth thermal gradient from the substrate to the top layer.

Co-deposition of multiple targets using multiple electron beam (e-beam) guns can be achieved to create thicker coatings as well as layered structures. For example, two targets with the same material type can be used at the same time. Each target can be hit by a different electron beam gun. This can increase the deposition rate and the thickness of the protective layer. In another embodiment, the two targets can be different ceramic materials. The first electron beam gun can collide with the first target to deposit the first protective layer, and the second electron beam gun then has a different material composition than the first protective layer. It can collide with a second target to form a second protective layer with it.

Post-coating heat treatment can be used to achieve improved coating properties. For example, it can be used to alter an amorphous coating into a crystalline coating with higher corrosion resistance. Another embodiment is for improving the bonding strength of the coating to the substrate by forming a reaction zone or transition layer.

In one embodiment, multiple lids and / or nozzles are processed in parallel within the IAD chamber. For example, in one embodiment, up to five lids and / or nozzles can be processed in parallel. Each lid or nozzle can be supported by a different fixture. Alternatively, a single fixture may be configured to hold multiple lids and / or nozzles. The fixture can move the lid and / or nozzle supported during deposition.

In one embodiment, the fixture for holding the lid and / or nozzle is a metal component (eg, cold rolled steel) or ceramics (eg, Al).₂O₃, Y₂O₃) Etc. can be designed. Fixtures can be used to support lids and / or nozzles above or below material sources and electron beam guns. Fixtures can have a chucking function for safer and easier handling and for chucking the lid and / or nozzle during coating. In addition, the fixture can have the function of changing or aligning the lid and the nozzle. In one embodiment, the fixture can be rearranged and / or rotated around one or more axes to orient the supported lid or nozzle towards the raw material. Fixtures can also be rearranged to change working distance and / or angle of incidence before and / or during deposition. Fixtures can have cooling or heating channels to control the temperature of the lid and nozzle during coating. Since IAD is a straightforward process, the ability to reposition and rotate the lid or nozzle may allow maximum coating coverage of 3D surfaces (eg holes).

3 to 4 show cross-sectional side views of articles (eg, lids and / or nozzles) covered with one or more thin film protective layers. Al₂O₃Has high bending strength and high thermal conductivity, so the lid for the plasma etching reactor used in the conductor etching process is Al.₂O₃It can be a sintered ceramic such as. However, Al exposed to fluorochemistry₂O₃Form AlF particles as well as aluminum metal contamination on the wafer. Other materials can also be used for lids and / or nozzles.

Referring to FIG. 3, body 305 of article 300 includes a thin film stack 306 having a first thin film protective layer 308 and a second thin film protective layer 310. Alternatively, the article 300 can include only a single thin film protective layer 308 on the body 305. In one embodiment, the thin film protective layers 308, 310 have a thickness of up to about 300 μm. In a further embodiment, the thin film protective layer has a thickness of about 20 microns or less, and in one particular embodiment, it has a thickness between about 0.5 micron and about 7 micron. In one embodiment, the overall thickness of the thin film protective layer stack is 300 μm or less.

The thin film protective layers 308 and 310 are vaporized ceramic layers that can be formed on the main body 305 of the article 300 using an electron beam ion assisted vapor deposition (EB-IAD) process. EB-IAD deposited thin film protective layers 308, 310 can have relatively low film stress (eg, compared to film stress by plasma spraying or sputtering). Due to the relatively low membrane stress, the underside of the body 305 can be made very flat with respect to the body having a diameter of 12 inches so that it has a curvature of less than about 50 microns over the entire body. The IAD-deposited thin film protective layers 308, 310 can further have a porosity of less than 1%, and in some embodiments less than about 0.1%. This low porosity may allow the lid to provide an effective vacuum seal during processing. Therefore, the IAD-deposited protective layer is a dense structure that can have performance advantages for chamber lid or nozzle applications. In addition, the IAD-deposited protective layer can have a low crack density and high adhesion to the body 305. Also, the IAD-deposited protective layers 308, 310 can be deposited without first roughening the top surface of the body 305 or performing a surface preparation step that consumes other times.

An example of ceramics that can be used to form the thin protective layer 208 is Y₃Al₅O₁₂, Y₄Al₂O₉, Er₂O₃, Gd₂O₃, Er₃Al₅O₁₂, Gd₃Al₅O₁₂, Y₄Al₂O₉And Y₂O₃-ZrO₂Solid solution (Y₂O₃-ZrO₂Includes either ceramic compounds, including (solid solution), or other previously identified ceramic materials. Other Er and / or Gd based plasma resistant rare earth oxides can also be used to form the thin film protective layers 308, 310. In one embodiment, the same ceramic material is not used for two adjacent thin film protective layers. However, in another embodiment, the adjacent layers may be made of the same ceramics.

Lids and nozzles with an IAD thin film protective layer can be used in applications where a wide range of temperatures are applied. For example, lids and nozzles with an IAD thin film protective layer can be used in processes with temperatures from 0 ° C to 1000 ° C. The lid and nozzle can be used at high temperatures (eg, at or above 300 ° C) without cracks due to thermal shock.<tables num="1"><img file="JP6929397B2_D0001.tif" /></tables>

Table 1 shows 92% Al₂O₃(Alumina) relative to substrate and 92% Al₂O₃The material properties for various IAD thin film protective layers that coat the substrate are shown. In the table, "C" represents a crystal structure and "A" represents an amorphous structure. As shown, the alumina substrate has an insulation breakdown voltage of 363 volts / mil (V / mil). In contrast, Y₄Al₂O₉And Y₂O₃-ZrO₂A 5 micron (μm) coating of IAD-deposited ceramic compounds containing a solid solution of has an insulation breakdown voltage of 427 V (much greater than the normalized value of 363 volt / mil for alumina). The 5 μm coating of IAD-deposited YAG has an insulation breakdown voltage of 1223 V. IAD Accumulated Er₂O₃The 5 μm coating has an insulation breakdown voltage of 527 V. A 5 μm coating of IAD-deposited EAG has an insulation breakdown voltage of 900 V. IAD deposited Y₂O₃The 5 μm coating has an insulation breakdown voltage of 1032 V. The 5 μm coating of IAD-deposited YZ20 has an insulation breakdown voltage of 423 V. IAD deposited YF₃The 5 μm coating has an insulation breakdown voltage of 522 V.

The volume resistance of alumina is about 0.01 × 10 at room temperature.¹⁶(0.01E16) Ω cm. The volume resistance of the ceramic compound thin film protective layer is about 4.1E 16Ω · cm at room temperature, and the volume resistance of the YAG thin film protective layer is about 11.3E 16Ω · cm at room temperature.

The dielectric constant of alumina is about 9.2, the dielectric constant of the ceramic compound thin film is about 9.83, the dielectric constant of the YAG thin film is about 9.76, and Er.₂O₃The dielectric constant of the thin film is about 9.67, and the dielectric constant of the EAG thin film is about 9.54. The loss positive contact of alumina is about 5E-4, the loss positive contact of the ceramic compound thin film is about 4E-4, and the loss positive contact of the YAG thin film is about 4E-4, Er.₂O₃The loss tangent of the thin film is about 4E-4, and the loss tangent of the EAG thin film is about 4E-4. The thermal conductivity of alumina is about 18 W / m · K, the thermal conductivity of the ceramic compound thin film is about 19.9 W / m · K, and the thermal conductivity of the YAG thin film is about 20.1 W / m · K. And Er₂O₃The thermal conductivity of the thin film is about 19.4 W / m · K, and the thermal conductivity of the EAG thin film is about 19.2 W / m · K.

The alumina substrate can have an initial roughness of about 8 to 16 microinch in one embodiment, and the initial roughness can be substantially unchanged in all of the thin film protective layers. The protective layer can be polished to less than 8 microinch after deposition to reduce surface roughness. In one embodiment, the protective layer is polished to a surface roughness of 6-8 microinch.

The adhesive strength of the thin film protective layer to the alumina substrate can exceed 28 megapascals (MPa) for the ceramic compound thin film and 32 MPa for the YAG thin film. Adhesive strength can be determined by measuring the amount of force used to separate the thin film protective layer from the substrate. Helmicity measures the sealing ability that can be achieved with a thin protective layer. Approximately 1E-6 cubic centimeters per second (cm) using alumina as shown³He leak rate of / s) can be achieved, He leakage rate of about 1.2E-9 can be achieved using ceramic compounds, He leakage rate of about 4.4E-10 can be achieved using YAG, Er₂O₃Can achieve a He leakage rate of about 5.5E-9 using the YF₃Can achieve a He leakage rate of about 2.6E-9, YZ20 can be used to achieve a He leakage rate of about 1.6E-7, and EAG can be used to achieve a He leakage rate of about 9.5E-10. Can be achieved. Lower He leakage rates indicate improved sealing. Each of the thin film protective layers of the examples is a typical Al₂O₃Has a lower He leakage rate.

Y₃Al₅O₁₂, Y₄Al₂O₉, Er₂O₃, Gd₂O₃, Er₃Al₅O₁₂, Gd₃Al₅O₁₂, And Y₄Al₂O₉And Y₂O₃-ZrO₂Each of the ceramic compounds, including the solid solution of, has a high hardness that can withstand wear during plasma treatment. As shown, alumina has a Vickers hardness (5 kgf) of about 12.14 gigapascal (GPa), ceramic compounds have a hardness of about 7.825 GPa, and YAG has a hardness of about 8.5 GPa. Have and Er₂O₃Has a hardness of about 5.509 GPa, YZ20 has a hardness of about 5.98 GPa, YF₃Has a hardness of about 3.411 GPa and EAG has a hardness of about 9.057 GPa. The measured wear rate of alumina is about 0.2 nanometer (nm / RF time) per high frequency time, the wear rate of ceramic compounds is about 0.14 nm / RF time, Er.₂O₃The wear rate of EAG is about 0.113 nm / RF time and the wear rate of EAG is about 0.176 nm / RF time.

In addition, Y₃Al₅O₁₂, Y₄Al₂O₉, Er₂O₃, Gd₂O₃, Er₃Al₅O₁₂, Gd₃Al₅O₁₂It should be noted that, in some embodiments, the ceramic compounds can be modified such that the properties and characteristics of the materials identified above can vary by up to 30%. Therefore, the values described for these material properties should be understood as achievable values in the examples. The ceramic thin film protective layer described herein should not be construed as limited to the values provided.

FIG. 4 shows a cross-sectional side view of another embodiment of the article 400 in which the thin film protective layer stack 406 is deposited on the body 405 of the article 400. Article 400 is similar to Article 400, except that the thin film protective layer stack 406 has four thin film protective layers 408, 410, 415, 418.

The thin film protective layer stack (eg, illustrated) can have any number of thin film protective layers. The thin film protective layers in the stack can all have the same thickness, or they can have varying thicknesses. Each of the thin protective layers can have a thickness of less than about 20 microns in some embodiments. In one embodiment, the first layer 408 can have a thickness of 10 microns and the second layer 410 can have a thickness of 10 microns. In another embodiment, the first layer 408 can be a YAG layer with a thickness of 5 microns and the second layer 410 can be a compound ceramics layer with a thickness of 5 microns. The third layer 415 can be a YAG layer having a thickness of 5 microns, and the fourth layer 418 can be a compound ceramics layer having a thickness of 5 microns.

The choice of the number of ceramic layers used and the composition of the ceramic layers may be based on the desired application and / or the type of article to be coated. The EAG and YAG thin film protective layers formed by IAD typically have an amorphous structure. In contrast, IAD-deposited compound ceramics and Er₂O₃The layer typically has a crystalline or nanocrystalline structure. Crystal and nanocrystalline ceramic layers can generally have higher corrosion resistance than amorphous ceramic layers. However, in some cases, thin film ceramic layers with crystalline or nanocrystalline structures will occasionally experience vertical cracks (cracks running approximately perpendicular to the coated surface, approximately in the film thickness direction). there is a possibility. Such vertical cracks can result from lattice mismatches and can be a point of attack for plasma chemistry. Each time the article is heated and cooled, the thermal expansion coefficient mismatch between the thin film protective layer and the substrate covering it can cause stress on the thin film protective layer. Such stress can be concentrated in vertical cracks. This can cause the thin film protective layer to eventually peel off and separate from the substrate that covers it. In contrast, in the absence of vertical cracks, the stress is distributed almost evenly over the entire thin film. Therefore, in one embodiment, the first layer 408 in the thin film protective layer stack 406 is amorphous ceramics (eg YAG or EAG) and the second layer 410 in the thin film protective layer stack 406 is crystalline or nanocrystalline ceramics. (For example, ceramic compounds or Er₂O₃). In such an embodiment, the second layer 410 can provide higher plasma resistance than the first layer 408. By forming the second layer 410 on the first layer 408 rather than directly on the body 405, the first layer 408 acts as a buffer, thereby minimizing the lattice mismatch of subsequent layers. In this way, the life of the second layer 410 can be increased.

In another embodiment, the body, Y₃Al₅O₁₂(YAG), Y₄Al₂O₉, Er₂O₃, Gd₂O₃, Er₃Al₅O₁₂, Gd₃Al₅O₁₂, Y₄Al₂O₉And Y₂O₃-ZrO₂Each of the ceramic compounds, including the solid solution of, and the other ceramics can have different thermal expansion coefficients. The greater the thermal expansion coefficient mismatch between two adjacent materials, the more likely one of those materials will eventually crack, peel off, or otherwise lose its bond with the other material. Become bigger. Protective layer stacks 306, 406 can be formed to minimize thermal expansion coefficient inconsistencies between adjacent layers (or between layers and bodies 305, 405). For example, the body 405 can be alumina, the EAG can have a thermal expansion coefficient closest to the thermal expansion coefficient of alumina, followed by the thermal expansion coefficient of YAG, followed by the thermal expansion coefficient of compound ceramics. Continue. Therefore, in one embodiment, the first layer 408 can be EAG, the second layer 410 can be YAG, and the third layer 415 can be compound ceramics.

In another embodiment, the layers in the protective layer stack 406 can be alternating layers of two different ceramics. For example, the first layer 408 and the third layer 415 can be YAG, and the second layer 410 and the fourth layer 418 can be compound ceramics. Such alternating layers have the same advantages as those described above when one material used in the alternating layers is amorphous and the other material used in the alternating layers is crystalline or nanocrystal. Can be provided.

In some embodiments, one or more layers in the thin film protective layer stacks 306, 406 are transition layers formed using heat treatment. When the main bodies 305 and 405 are ceramic bodies, high temperature heat treatment can be performed in order to promote mutual diffusion between the thin film protective layer and the main body. The heat treatment may also be performed to promote mutual diffusion between adjacent thin film protective layers or between a thick protective layer and the thin film protective layer. In particular, the transition layer can be a non-porous layer. The transition layer can serve as a diffusion bond between the two ceramics and can provide improved adhesion between adjacent ceramics. This can help prevent the protective layer from cracking, peeling or peeling off during plasma treatment.

The heat treatment can be a heat treatment at a maximum of about 1400 to 1600 ° C. for a maximum of about 24 hours (for example, 3 to 6 hours in one embodiment). This can form a mutual diffusion layer between the first thin film protective layer and one or more of adjacent ceramic bodies or the second thin film protective layer. Ceramic body is Al₂O₃And the protective layer is compound ceramics Y₄Al₂O₉And solid solution Y_2-xZr_xO₃(Y₂O₃-ZrO₂If composed of solid solution), Y₃Al₅O₁₂(YAG) An interface layer is formed. Similarly, heat treatment Ers the transition layer of EAG.₂O₃And Al₂O₃Form between. Heat treatment also Y the transition layer of YAG₂O₃And Al₂O₃Form between. Heat treatment also Gd GAG₂O₃And Al₂O₃Form between. Al₂O₃The heat treatment of Itria Stabilized Zirconia (YSZ) above is Y₄Al₂O₉(YAM) and solid solution Y_2-xZr_xO₃It is possible to form a transition layer of the compound ceramics of. Other transition layers may be formed between other adjacent ceramics.

In one embodiment, the colorant is added during the deposition of the first protective layers 308, 408. Thus, if the second protective layers 310, 410 are worn out, the operator can have a visual cue when it is time to regenerate or replace the lid or nozzle.

FIG. 5A shows a perspective view of a chamber lid 505 having a plasma resistant layer 510 of a thin film rare earth oxide according to an embodiment. FIG. 5B shows a cross-sectional side view of the chamber lid 505 having the plasma resistant layer 510 of the thin film rare earth oxide according to the embodiment. The chamber lid 505 includes a hole 520 that can be in the center of the lid or elsewhere in the lid. The lid 505 can also have a lip 515 that contacts the wall of the chamber while the lid is closed. In one embodiment, the protective layer 510 does not cover the lip 515. A hard or soft mask covering the lip 515 during deposition may be used to ensure that the protective layer does not cover the lip 515. The mask can then be removed after deposition. Alternatively, the protective layer 510 can coat the entire surface of the lid. Therefore, the protective layer 510 can be placed on the side wall of the chamber during the process. Also, in some embodiments, the outer wall of the lid 505 may be coated with a plasma resistant layer 555.

As shown in FIG. 5B, the protective layer 510 can have a side wall 530 that coats the interior of the hole 520. The side wall 530 of the protective layer 510 can be thicker near the surface of the lid 505 and can be gradually thinner as it gets deeper into the hole 520. In such an embodiment, the side wall portion 530 does not have to coat the entire side wall portion of the hole 520.

FIG. 5C shows a perspective view of a chamber nozzle 550 having a plasma resistant layer 555 of rare earth oxide according to one embodiment. As shown, the rare earth oxide plasma resistant layer 555 can coat the ends and side walls of the chamber nozzle 550. The chamber nozzle 550 can be inserted into the lid 505. In one embodiment, the nozzle 550 comprises a lip 565 resting on a lid 505. The lip 565 does not have to be coated with the plasma resistant layer 555. Alternatively, the lip 565 may be coated with a plasma resistant layer 555.

FIG. 6 shows an embodiment of the process 600 for forming a thin film protective layer on the chamber lid or the body of the chamber nozzle. In block 605 of process 600, a chamber lid or nozzle is provided. The lid or nozzle can have a bulk sintered ceramic body. The bulk sintered ceramic body is Al₂O₃, Y₂O₃, SiO₂, Or Y₄Al₂O₉And Y₂O₃-ZrO₂It can be a ceramic compound containing a solid solution of.

At block 620, an ion-assisted deposition (IAD) process is performed, which deposits a rare earth oxide protective layer on at least one surface of the lid or nozzle. In one embodiment, an electron beam ion assisted deposition process (EB-IAD) is performed. The IAD process can be performed by melting the deposited material and causing ions to collide with the material.

The thin protective layer is Y₃Al₅O₁₂, Y₄Al₂O₉, Er₂O₃, Gd₂O₃, Er₃Al₅O₁₂, Gd₃Al₅O₁₂Or, Y₄Al₂O₉And Y₂O₃-ZrO₂It can be a ceramic compound with a solid solution of the above, or other rare earth oxides described herein. The deposition rate of the thin film protective layer, in one embodiment, can be about 0.02 to 20 angstroms per second (A / s) and can be varied by adjusting the deposition parameters. In one embodiment, a deposition rate of 0.25 to 1 A / s is initially used to achieve a coating that fits and adheres well on the substrate. A deposition rate of 2-10 A / s is then used to deposit the rest of the thin film protective layer, which allows a thicker coating to be achieved in a shorter period of time. The thin protective layers can be very compatible, can be uniform in thickness, and can have good adhesion to the body / substrate on which they are deposited.

In one embodiment, the material comprises a colorant that gives the deposited protective layer a particular color. An example of a colorant that can be used is Nd₂O₃, Sm₂O₃And Er₂O₃including. Other colorants can also be used.

At block 625, a decision is made as to whether to deposit an additional thin film protective layer. If an additional thin film protective layer is deposited, the process continues to block 630. In block 630, another thin film protective layer is formed on the first thin film protective layer. The other thin film protective layer may be made of ceramics different from the ceramics of the first thin film protective layer. Alternatively, the other thin film protective layer may be composed of the same ceramics or a plurality of ceramics used to form the first protective layer.

In one embodiment, the other thin protective layer does not contain a colorant. Therefore, subsequent protective layers may have a different color than the bottom protective layer, even if they are composed of approximately the same ceramic material. This causes the lid or nozzle to change color when the protective layer stack is eroded to the bottom protective layer. The color change can inform the operator that it is time to replace the lid or nozzle of the processing chamber.

After the subsequent protective layer has been deposited, the method returns to block 625. If no additional thin film protective layer is applied at block 625, the process proceeds to block 635. At block 635, the surface of the protective layer is polished. The surface can be polished using chemical mechanical polishing (CMP) or other polishing methods. In one embodiment, the surface of the top protective layer is polished to a surface roughness of 8 microinch or less. In another embodiment, the surface of the top protective layer is polished to a surface of 6 microinch or less.

Process 600 can be performed on new lids and nozzles, or on used lids and nozzles to regenerate used lids and nozzles. In one embodiment, used lids and nozzles are polished prior to performing process 600. For example, the previous protective layer can be removed by polishing before performing process 600.

The IAD process allows high energy particles to be controlled by a high energy ion (or other particle) source independently of other deposition parameters. Depending on the energy (eg, velocity), the density and angle of incidence of the high energy ion flux, the composition, structure, crystal orientation and particle size of the thin film protective layer can be manipulated. Additional adjustable parameters are the temperature of the article during deposition, as well as the duration of deposition. Ion energy can be roughly classified into low energy ion assist and high energy ion assist. The low energy ion assist can include a voltage of about 230V and a current of about 5A. High energy ion assist can include a voltage of about 270V and a current of about 7A. The low and high energies for ion assist are not limited to the values mentioned herein. High and low level designations may further depend on the type of ions used to perform the IAD process and / or the geometry of the chamber used. Ions are fired at a higher rate with high energy ion assist than with low energy ion assist. The temperature of the substrate (article) during deposition is roughly divided into low temperature (about 120 to 150 ° C in one embodiment, which is a typical room temperature) and high temperature (about 270 ° C in one embodiment). be able to. Due to the high temperature IAD deposition process, the lid or nozzle may be heated before and during deposition.<tables num="2A"><img file="JP6929397B2_D0002.tif" /></tables><tables num="2B"><img file="JP6929397B2_D0003.tif" /></tables>

Tables 2A-2B show the thin film protective layers of multiple examples formed using IADs with various deposition parameters. Experimental results identify an optimized coating process based on a multifactorial experimental planning method (DOE) that changes ion-assisted energy, deposition rate, and temperature to obtain compatible dense microstructures. .. The coating is characterized in terms of material properties (microstructure and / or crystalline phase) and mechanical properties (hardness and adhesion), as well as crack density and vacuum sealability. Optimization of the IAD coating process can produce IAD coatings with high density thin films (up to ~ 300 microns thick) with low residual stress. Most parameters optimized, can be used for most of the rare earth oxide-based coating material.

Y₄Al₂O₉And Y₂O₃-ZrO₂Six different examples are shown for a thin film protective layer formed from a ceramics compound with a solid solution of. The compound ceramic thin film protective layer of the first embodiment has a thickness of 5 microns, a low energy ion assist and sintered plug target, a deposition temperature of 270 ° C, and a deposition rate of 2 angstroms per second (A / s). Formed using IAD by. X-ray diffraction showed that the compound ceramic thin film protective layer of the first example had a crystal structure. The compound ceramic thin film protective layer of the first example also had a hardness of 4.11 GPa, and visual inspection showed good compatibility with the underlying substrate, as well as some vertical cracks and some spikes. ..

The compound ceramics thin film protective layer of the second embodiment has a thickness of 6 microns, a low energy ion assist and sintered plug target, a deposition temperature of 270 ° C, and 1 A / s for the first 2 microns. It was formed using an IAD with a deposition rate of 2 A / s for the deposition rate followed by 4 microns. X-ray diffraction showed that the compound ceramics thin film protective layer of the second example had a nanocrystal structure (partially crystalline and partially amorphous inside). When used as a seal, the compound ceramics thin film protective layer of the second embodiment is at least 5E-6 cubic centimeters per second (cm).³The vacuum up to / s) could be maintained. Visual inspection of the compound ceramics thin film protective layer of the second example showed good compatibility and less vertical cracks than the compound ceramics thin film protective layer of the first example.

The compound ceramics thin film protective layer of the third embodiment has a thickness of 5 microns and uses IAD with low energy ion assist and sintered plug target, deposition temperature of 270 ° C, and deposition rate of 1 A / s. Been formed. X-ray diffraction showed that the compound ceramic thin film protective layer of the third example had a nanocrystal structure. When used as a seal, the compound ceramics thin film protective layer of the third embodiment has a minimum of 6.3E-6 cm.³I was able to maintain a vacuum up to / s. Visual inspection of the compound ceramics thin film protective layer of the third example showed good compatibility and less vertical cracks than the compound ceramics thin film protective layer of the first example.

The compound ceramics thin film protective layer of the fourth embodiment has a thickness of 5 microns, a high energy ion assist and sintered plug target, a deposition temperature of 270 ° C, and 1 A / s for the first micron. It was formed using IAD with a deposition rate of 2 A / s for the subsequent 4 microns. X-ray diffraction showed that the compound ceramic thin film protective layer of the third example had a substantially amorphous structure. When used as a seal, the compound ceramics thin film protective layer of the third embodiment has a minimum of 1.2E-9 cm.³I was able to maintain a vacuum up to / s. Visual inspection of the compound ceramics thin film protective layer of Example 4 showed good compatibility, a smooth surface, and very few vertical cracks. The compound ceramic thin film protective layer of the fourth embodiment has a hardness of 7.825 GPa.

The compound thin film protective layer of the fifth example had the same parameters as the compound thin film protective layer of the fourth example, but the deposition temperature was formed using a room temperature (about 120 to 150 ° C) and a roasted powder target. The compound thin film protective layer of the fifth example showed the same characteristics as the compound thin film protective layer of the fourth example.

The compound ceramics thin film protective layer of the sixth embodiment has a thickness of 5 microns, a high energy ion assist and calcined powder target, a deposition temperature of 270 ° C, and 1 A / s for the first micron. It was formed using IAD with a deposition rate of 4 A / s for the subsequent 4 microns. X-ray diffraction showed that the compound ceramic thin film protective layer of the third example had a substantially amorphous structure. When used as a seal, the compound ceramics thin film protective layer of the third embodiment has a minimum of 1.2E-9 cm.³I was able to maintain a vacuum up to / s. The compound ceramic thin film protective layer of the fourth example has a hardness of 7.812 GPa.

The YAG thin film protective layer of the first embodiment has a thickness of 5 microns and uses IAD with low energy ion assist and molten mass target, deposition temperature of 270 ° C, and deposition rate of 2.5 A / s. Was formed. X-ray diffraction showed that the first YAG ceramic thin film protective layer had an amorphous structure. The 1st YAG Ceramics Thin Protective Layer also had a hardness of 5.7 GPa and visual inspection showed good compatibility, minimal cracking and a smooth surface.

The YAG thin film protective layer of the second embodiment has a thickness of 5 microns, a high energy ion assisted and molten mass target, a deposition temperature of 270 ° C, and 1 A / s for the first 1 micron. It was formed using IAD with a deposition rate of 2 A / s for the subsequent 4 microns. X-ray diffraction showed that the second YAG thin film protective layer had an amorphous structure. The second YAG thin film protective layer also had a hardness of 8.5 GPa and visual inspection showed good compatibility, reduced cracks compared to the first YAG thin film, and a smooth surface.

The thin film protective layer stack of one example with alternating layers of compound ceramics and YAG has a thickness of 5 microns and has a low energy ion assist, an IAD of 270 ° C deposition temperature, and an IAD of 2 A / s deposition rate. Formed using. X-ray diffraction showed that the alternating layers were amorphous (relative to the YAG layer) and crystalline or nanocrystals (relative to the compound ceramics layer). Visual inspection showed a reduction in vertical cracks in the compound ceramics layer.

Er of the first embodiment₂O₃The thin film protective layer had a thickness of 5 microns and was formed using low energy ion assist and a sintered mass target, an IAD with a deposition temperature of 270 ° C, and an IAD with a deposition rate of 2 A / s. X-ray diffraction is the 1st Er₂O₃It was shown that the ceramic thin film protective layer has a crystal structure. Visual inspection showed good compatibility and vertical cracks.

Er of the second embodiment₂O₃The thin protective layer has a thickness of 5 microns, a high energy ion assisted and sintered mass target, a deposition temperature of 270 ° C, and a deposition rate of 1 A / s for the first 1 micron, followed by. It was formed using IAD with a deposition rate of 2 A / s for 4 microns. X-ray diffraction is the second Er₂O₃It was shown that the ceramic thin film protective layer has a crystal structure. Visual inspection shows good compatibility and 1st Er₂O₃It showed smaller vertical cracks than the ceramic thin film protective layer.

The EAG thin film protective layer of the first embodiment has a thickness of 7.5 microns, a high energy ion assist and calcined powder target, a deposition temperature of 270 ° C, and an deposition of 1 A / s for the first micron. Formed using IAD with a rate, followed by a deposition rate of 2 A / s for the micron. X-ray diffraction showed that the first EAG ceramics thin film protective layer had an amorphous structure and the layer had a hardness of 8.485 GPa. Visual inspection showed good compatibility and minimal cracking.

The EAG thin film protective layer of the second example has a thickness of 7.5 microns, high energy ion assist, deposition temperature of 120-150 ° C, and deposition rate of 1 A / s for the first 1 micron, followed by It was formed using IAD with a deposition rate of 2 A / s relative to the micron. X-ray diffraction showed that the second EAG ceramic thin film protective layer had an amorphous structure and the layer had a hardness of 9.057 GPa. Visual inspection showed good compatibility and fewer cracks compared to the 1st EAG Ceramics Thin Protective Layer.

The EAG thin film protective layer of the third embodiment has a thickness of 5 microns and has a high energy ion assist and calcined powder target, and a deposition rate of 1 A / s for the first 1 micron, for subsequent microns. It was formed using IAD with a deposition rate of 2 A / s. X-ray diffraction showed that the third EAG ceramic thin film protective layer had an amorphous structure.

Y of one embodiment₂O₃The thin protective layer has a thickness of 5 microns, with high energy ion assist and melted mass targets, a temperature of 270 ° C, and a deposition rate of 1 A / s for the first 1 micron, followed by micron. In contrast, it was formed using IAD with a deposition rate of 2 A / s. X-ray diffraction showed that the third EAG ceramic thin film protective layer had a crystalline structure.

The YZ20 thin film protective layer of one example has a thickness of 5 microns, a high energy ion assist and powder target, a temperature of 120-150 ° C, and a deposition rate of 1 A / s for the first 1 micron. It was formed using IAD with a deposition rate of 2 A / s for subsequent microns. X-ray diffraction showed that the YZ20 thin film protective layer had a crystalline structure. When used as a seal, the YZ20 thin film protective layer should be at least 1.6E-7 cm³I was able to maintain a vacuum up to / s. The YZ20 thin film protective layer had a hardness of 5.98 GPa.

YF of one example₃The thin protective layer has a thickness of 5 microns, high energy ion assist, a temperature of 120-150 ° C, and a deposition rate of 1 A / s for the first 1 micron, 2 A / s for subsequent microns. It was formed using IAD with the deposition rate of s. X-ray diffraction is YF₃It was shown that the thin film protective layer has an amorphous structure. YF when used as a seal₃Thin protective layer is at least 2.6E-9cm³I was able to maintain a vacuum up to / s. YF₃The thin film protective layer had a hardness of 3.411 GPa.<tables num="3"><img file="JP6929397B2_D0004.tif" /></tables>

Table 3 shows the optimized IAD processing parameters for coating the chamber lid or nozzle according to one embodiment. Table 3 further shows the range of processing parameters that can be used in some embodiments to deposit the thin film protective layer. In other embodiments, a wider range of some of the processed values can be used. In one embodiment, the IAD process has a voltage of 150 to 270 volts (V), a current of 5 to 7 amps (A), a temperature of 100 to 270 ° C, and a deposition rate of 0.01 to 20 angstroms per second (A / s). , 0-90 degrees incident angle, and 10-300 inches (in.) Working distance. In another embodiment, the IAD process has a voltage of 50 to 500 V, a current of 1 to 50 A, a temperature of 20 to 500 ° C, a deposition rate of 0.01 to 20 A / s, a working distance of 10 to 300 inches, and 10. Performed with an incident angle of ~ 90 degrees.

The deposition rate of the coating can be controlled by adjusting the amount of heat applied by the electron beam. Ion-assisted energy can be used to densify the coating and to accelerate the deposition of material on the surface of the lid or nozzle. The ion assist energy can be changed by adjusting the voltage and / or current of the ion source. Currents and voltages can be adjusted to manipulate the stress of the coating to achieve high and low coating densities and to affect the degree of crystallinity of the coating. The ion assist energy can be changed from 50 to 500V and 1 to 50A. The deposition rate can be varied from 0.01 to 20 A / s.

In one embodiment, Y₄Al₂O₉And Y₂O₃-ZrO₂The high ion assist energy used in ceramic compounds containing solid solutions of Y forms an amorphous protective layer.₄Al₂O₉And Y₂O₃-ZrO₂The low ion-assisted energy used in ceramic compounds, including solid solutions of the above, forms a crystalline protective layer. Ion-assisted energy can also be used to change the chemical theory of protective layers. For example, a metal target can be used and the metal material is transformed into a metal oxide during deposition by incorporating oxygen ions on the surface of the lid or nozzle. Also, by using an oxygen gun, the level of any metal oxide coating can be varied and optimized to achieve the desired coating properties. For example, most rare earth oxides lose oxygen inside the vacuum chamber. Oxygen deficiency in the oxide coating material can be compensated for by allowing more oxygen to flow out inside the chamber.

The coating temperature can be controlled by using a heater (eg, a heating lamp) and by controlling the deposition rate. High deposition rates typically increase the temperature of the lid or nozzle. The deposition temperature can be changed to control film stress, crystallinity, and the like. The temperature can be changed from 20 ° C to 500 ° C.

The working distance can be adjusted to change the uniformity, density and deposition rate. The working distance can be varied from 10 to 300 inches. The deposition angle can be changed by the position of the electron beam gun or electron beam furnace, or by changing the position of the lid or nozzle in connection with the electron beam gun or electron beam furnace. By optimizing the deposition angle, a uniform coating can be achieved in a three-dimensional geometry. The deposition angle can be varied from 0 to 90 degrees, and in one embodiment from 10 to 90 degrees.

In one embodiment, the IAD process is performed using a voltage of about 188V in combination with other processing parameters that have any of the relevant processing parameter ranges. In one embodiment, the IAD process is performed using a current of about 7A in combination with other processing parameters that have any of the relevant processing parameter ranges. In one embodiment, the IAD process is performed using a temperature of about 150 ° C. in combination with other processing parameters that have any of the relevant processing parameter ranges. In one embodiment, the IAD process is performed using a deposition rate of 1 A / s in combination with other processing parameters that have any of the relevant processing parameter ranges. In a further embodiment, a deposition rate of 2 A / s is used until the deposited thin film reaches a thickness of 1 μm, after which a deposition rate of 1 A / s is used. In another embodiment, a deposition rate of 0.25 to 1 A / s is used first, thereby achieving a coating that fits well on the substrate and adheres well. A deposition rate of 2-10 A / s is then used to deposit the rest of the thin film protective layer, which allows a thicker coating to be achieved in a shorter amount of time.

In one embodiment, the IAD process is performed using an incident angle of approximately 30 degrees in combination with other processing parameters that have any of the relevant processing parameter ranges. In one embodiment, the IAD process is performed using a working distance of approximately 50 inches in combination with other processing parameters that have any of the relevant processing parameter ranges.

FIG. 7 is a dielectric etched CF containing the erosion rates of several different IAD coatings produced according to the embodiments described herein.₄Shows the erosion rate of various materials exposed to chemistry. As shown, the erosion rate of 92% alumina is about 1.38 micron per high frequency time (μm / Rf time) and the erosion rate of 99.8% alumina is about 1.21 μm / Rf time, IAD deposited. The erosion rate of YAG is about 0.28 μm / Rf hours, the erosion rate of IAD-deposited EAG is about 0.24 μm / Rf hours, and the IAD-deposited Y₂O₃The erosion rate of is about 0.18 μm / Rf time and IAD deposited Er₂O₃The erosion rate of is about 0.18 μm / Rf hours, and the erosion rate of IAD-deposited compound ceramics is about 0.18 μm / Rf hours. The high frequency time is one hour of processing.

FIGS. 8 to 9 show the erosion rate of the thin film protective layer formed according to the embodiment of the present invention. Figure 8 shows CH₄/ Cl₂The erosion rate of the thin film protective layer when exposed to plasma chemistry is shown. As shown, the IAD-deposited thin film protective layer is Al₂O₃Shows much improved corrosion resistance compared to. For example, alumina with a purity of 92% showed an erosion rate of about 18 nanometers (nm / RF time) per high frequency time, and alumina with a purity of 99.8% showed an erosion rate of about 56 nm / RF time. .. In contrast, the IAD-deposited compound ceramics thin film protective layer showed an erosion rate of about 3 nm / RF hours, and the IAD-deposited YAG thin film protective layer showed an erosion rate of about 1 nm / RF hours.

Figure 9 shows H₂/ NF₃The erosion rate of the thin film protective layer when exposed to plasma chemistry is shown. As shown, the IAD-deposited thin film protective layer is Al₂O₃Shows much improved corrosion resistance compared to. For example, alumina with a purity of 92% showed an erosion rate of about 190 nm / RF hours, and alumina with a purity of 99.8% showed an erosion rate of about 165 nm / RF hours. In contrast, the IAD-deposited YAG thin film protective layer exhibited an erosion rate of approximately 52 nm / RF hours. Similarly, the compound ceramics thin film protective layer deposited using IAD with low energy ions showed an erosion rate of about 45 nm / RF time, and the compound ceramics thin film protective layer deposited using IAD with high energy ions. Showed an erosion rate of about 35 nm / RF time. EAG thin film protective layers deposited using IAD at high deposition temperatures (eg, about 270 ° C) show erosion rates at about 95 nm / RF hours and low deposition temperatures (eg, about 120-150 ° C). The EAG thin film protective layer deposited using IAD in showed an erosion rate of about 70 nm / RF time. Er deposited using IAD with high energy ions₂O₃The thin protective layer showed an erosion rate of about 35 nm / RF time.

FIGS. 10-11 show the roughness profile for the thin film protective layer formed according to the embodiment of the present invention. Figure 10 shows CH for 100 RF hours₄/ Cl₂The surface roughness profile of the thin film protective layer in Fig. 8 before and after exposure to plasma chemistry is shown. As shown, the IAD-deposited thin film protective layer is CH for 100 RF hours.₄/ Cl₂Shows minimal change in surface roughness after exposure to plasma chemistry.

Figure 11 shows H for 35 RF hours.₂/ NF₃The surface roughness profile of the thin film protective layer shown in FIG. 9 before and after exposure to plasma chemistry is shown. As shown, the IAD-deposited thin film protective layer is H for 35 RF hours.₂/ NF₃Shows minimal change in surface roughness after exposure to plasma chemistry.

FIG. 12 is a low bias CF that includes the erosion rates of multiple different IAD coatings produced according to the embodiments described herein.₄-CHF₃Shows the erosion rate of various materials exposed to trench chemistry. As shown, the erosion rate of 92% alumina is about 0.26 micron every high frequency time (μm / Rf time), the erosion rate of IAD-deposited EAG is about 0.18 μm / Rf time, of the IAD-deposited YAG. The erosion rate is about 0.15 μm / Rf time, the erosion rate of plasma-deposited compound ceramics is about 0.09 μm / Rf time, and IAD-deposited Y₂O₃The erosion rate of IAD-deposited ceramic compounds is about 0.07 μm / Rf hours, and the erosion rate of bulk Y is about 0.07 μm / Rf hours.₂O₃The erosion rate of the bulk ceramic compound is about 0.07 μm / Rf time, the erosion rate of the bulk ceramic compound is about 0.065 μm / Rf time, and the IAD-deposited Er.₂O₃The erosion rate of is about 0.05 μm / Rf time. These materials are CF with high bias₄-CHF₃Similar etching results occur when etched using trench chemistry. For example, the etching rate of 92% alumina at high bias is about 1.38 μm / Rf hours, the erosion rate of IAD-deposited EAG is about 0.27 μm / Rf hours, and the erosion rate of IAD-deposited YAG is about 0.27 μm / Rf hours. , Approximately 0.27 μm / Rf hours, and the erosion rate of plasma-deposited compound ceramics is approximately 0.35 μm / Rf hours, IAD-deposited Y₂O₃The erosion rate of the IAD-deposited ceramic compound is about 0.19 μm / Rf time, and the erosion rate of the bulk Y is about 0.19 μm / Rf time.₂O₃The erosion rate of bulk ceramic compounds is about 0.4 μm / Rf hours, and the erosion rate of bulk ceramic compounds is about 0.4 μm / Rf hours, and IAD-deposited Er.₂O₃The erosion rate of is about 0.18 μm / Rf time.<tables num="4"><img file="JP6929397B2_D0005.tif" /></tables>

The lids and nozzles coated with the IAD-deposited thin film protective layer formed according to embodiments of the present invention have the result of metal contamination that meets the indicated specifications shown in Table 4. The table identifies metal pollutants, detection limits, specification limits, first test results, and second test results. The detection limit is the minimum detectable level of contamination. The specification limit is the number of atoms (atoms / cm) per square centimeter found on a tested substrate (eg, wafer).²). As shown, within two different metal contamination tests, the levels of aluminum and yttrium contamination are 100 atoms / cm.²Less than, and levels of nickel, iron, chromium, copper, titanium, and calcium contamination are 10 atoms / cm²Was less than. For each of the tests, Y₄Al₂O₉And Y₂O₃-ZrO₂Covers and nozzles containing a thin protective layer of ceramic compound containing a solid solution of were used during the test process. Levels of metal contamination were measured after each test process. Similar contamination results can be achieved using other IAD-deposited thin film protective layers formed according to the embodiments described herein.

Y₄Al₂O₉And Y₂O₃-ZrO₂After 100 RF hours of treatment with a lid and nozzle with a thin protective layer of ceramics compound containing a solid solution of, the overall particle contamination on the treated 300 mm wafer is about 50 particles over 65 nm in size. It was tested that there were about 40 particles over 90 nm in size and about 20 particles over 165 nm in size. The measured particle contamination is the total number of particles above a predetermined size on a 300 mm wafer. After 50 RF hours of treatment, overall particle contamination was tested with about 40 particles over 65 nm in size, about 30 particles over 90 nm in size, and about 18 particles over 165 nm in size. Was done.

The above description describes a number of specific details, such as examples of specific systems, components, methods, etc., in order to provide a good understanding of some embodiments of the present invention. However, it will be apparent to those skilled in the art that at least some embodiments of the present invention can be practiced without these specific details. In other examples, well-known components or methods are not described in detail or are presented in simple block diagram format so as not to unnecessarily obscure the invention. Therefore, the specific details described are merely examples. It is understood that certain implementations may differ from these exemplary details but are still within the scope of the present invention.

References to "one embodiment" or "one embodiment" throughout this specification shall include in at least one embodiment a particular configuration, structure, or property described in connection with that embodiment. Means. Therefore, the appearance of the phrase "in one embodiment" or "in one embodiment" in various places throughout the specification does not necessarily refer to the same embodiment. Also, the term "or" is intended to mean an inclusive "or" rather than an exclusive "or". As used herein, the term "about" or "approximately" is intended to mean that the nominal values presented are accurate within ± 30%.

The operations of the method within this specification are illustrated and described in a particular order, but the particular operation may be performed in the reverse order, or the particular operation may be performed at least in part at the same time as the other operations. The order of operations of each method can be changed as such. In another embodiment, the commands or sub-operations of different operations can be intermittent and / or alternating methods.

It should be understood that the above description is exemplary and intended to be non-limiting. By reading and understanding the above description, many other embodiments will become apparent to those skilled in the art. Therefore, the scope of the present invention should be determined with reference to the appended claims, along with the full range of equivalents to which such claims qualify.