Showerhead electrode for use in a plasma reaction chamber and showerhead electrode assembly

Shower head electrode and shower head electrode assembly for plasma reaction chamber

This creation is about showerhead electrodes used during plasma processing, especially about single crystal showerhead electrodes with improved gas distribution and temperature control.

The manufacture of integrated circuit chips generally starts with a thin-layer polishing sheet of a high-purity, single-crystal semiconductor material substrate (such as silicon or germanium) called "wafer", and each wafer will be formed on the wafer A series of physical and chemical processing steps for various circuit structures. During the manufacturing process, various techniques can be used to deposit various thin films on the wafer, such as thermal oxidation to produce silicon dioxide films; chemical vapor deposition to produce silicon, silicon dioxide, and silicon nitride films; And sputtering or other techniques used to produce other metal films.

After the film is deposited on the semiconductor wafer, a process called doping can be used to replace selected impurities into the semiconductor crystal lattice to produce unique semiconductor electrical properties. Afterwards, the doped silicon wafer can be uniformly coated with a thin layer of photosensitive or radiation-sensitive material called "photoresist". Then, a process called lithography can be used to transfer the tiny geometric patterns that define the electronic paths in the circuit onto the photoresist. During the photolithography process, the integrated circuit pattern can be drawn on a glass plate called a "mask", and then optically reduced, projected, and transferred to this photosensitive coating.

Afterwards, through a process called etching, the photoresist pattern that has undergone lithographic processing is transferred to the underlying crystalline surface of the semiconductor material. The vacuum processing chamber is generally used for etching and chemical vapor deposition (CVD, chemical vapor deposition) of materials on the substrate. It is performed by supplying etching or deposition gas to the vacuum chamber and applying a radio frequency (RF) field to the vacuum chamber. So far, the gas can be excited into a plasma state.

The reactive ion etching system typically consists of an etching chamber in which an upper electrode or anode and a lower electrode or cathode are arranged. The cathode is negatively biased with respect to the anode and the container wall. The wafer to be etched is covered by a suitable mask and placed directly on the cathode. Will e.g. CF₄, CHF3, CClF₃, HBr, Cl₂And SF₆Or a mixture of chemically reactive gases accompanied by O₂, N₂, He, or Ar are introduced into the etching chamber together and maintained at a pressure in the typical upper millitorr range. The upper electrode is a shower head electrode provided with a gas outlet, which allows the gas to evenly spread through the electrode to reach the chamber. The electric field established between the anode and the cathode can dissociate the reactive gas to form a plasma. The surface of the wafer is etched through the chemical interaction with the active ions and the momentum transfer of the ions that hit the surface of the wafer. The electric field generated by the electrode can attract ions to the cathode, causing the ions to strike the surface in a predominantly vertical direction, so that the process produces well-defined vertical etched sidewalls.

During the plasma processing of the semiconductor substrate, in order to achieve the desired plasma chemistry on the plasma exposed surface of the showerhead electrode, there is an urgent need for reliable and repeatable temperature control of the showerhead electrode. Co-owned US Published Patent Application Nos. 2009/0081878 and 2008/0308228 (the disclosures of which are hereby incorporated by reference) disclose temperature control modules for showerhead electrode assemblies.

The maintenance of the sprinkler electrode will become difficult due to the complicated installation and configuration. Co-license with the United States Non-Provisional Patent Application No. 12/216524 (filed on July 7, 2008), which discloses a single crystal shower head electrode, which is removably connected by a series of cam locks. Attached to the support plate. In the illustrated embodiment, the support plate has an annular convex portion for accommodating the cam lock, and the shower head electrode has an annular groove that engages with the convex portion on the support plate.

In some plasma processing, it is urgent to provide a gas outlet pattern that can more evenly distribute the processing gas in the chamber.

A clamped single crystal showerhead electrode is disclosed herein, which has improved gas distribution and temperature control.

This application claims the priority of U.S. Provisional Application No. 61/243,647 under 35 USC §119, and its title is "CLAMPED MONOLITHIC SHOWERHEAD ELECTRODE". The application was filed on September 18, 2009, and the entire content is hereby consolidated for provision. Reference.

According to one embodiment, a showerhead electrode for a plasma reaction chamber includes a central portion and a peripheral portion defined by the top and bottom surfaces of the showerhead electrode. The top surface includes a plane extending across the central portion and the peripheral portion, and the bottom surface is defined by a flat inner surface extending across the central portion and a stepped outer surface extending across the peripheral portion. The stepped outer surface includes at least one annular plane, the annular plane is used to define a thickened area of the showerhead electrode, and a plurality of surrounding partition cavities are located in the top surface of the peripheral portion, and the cavities are used for cams The lock is accommodated in it, and the cam lock is used to clamp the shower head electrode to a supporting plate. A plurality of gas outlets are located in the central part of the showerhead electrode, and the processing gas can pass through the gas outlet to be transported to the gap between the showerhead electrode and the lower electrode, and a wafer can be supported on the lower electrode. The gas outlets are arranged in a pattern with a central gas outlet and 13 gas outlet rows extending around. In the gas outlet row, the first row has 10 gas outlets and is about 0.5 inches away from the center of the shower head electrode, and the second row There are 18 gas outlets and the distance from the center is about 0.9 inches, the third row has 28 gas outlets and the distance from the center is about 1.4 inches, the fourth row has 38 gas outlets and the distance is about 1.8 inches from the center, and the fifth row has 46 gas outlets. And the distance from the center is about 2.3 inches, the sixth row has 56 gas outlets and the distance from the center is about 2.7 inches, the seventh row has 66 gas outlets and the distance from the center is about 3.2 inches, the eighth row has 74 gas outlets and the distance from the center is about 3.6 In the ninth row, there are 84 gas outlets and the distance from the center is about 4.1 inches, the tenth row has 94 gas outlets and the distance from the center is about 4.6 inches, and the eleventh row has 104 gas outlets and the distance from the center is about 5.1 inches. The second row has 110 gas outlets and is about 5.4 inches from the center, and the thirteenth row has 120 gas outlets and is about 5.7 inches from the center. A temperature sensor receiving hole in the top surface can be used to receive a temperature sensor.

The stepped outer surface may include a single step or a multi-step structure. This single step structure includes a single annular plane and inner and outer inclined surfaces. The inner inclined surface extends between the flat inner surface and the single annular plane, and the outer inclined surface lies between the single annular plane and the showerhead electrode. Extend between the outer edges.

This multi-step configuration comprising inner and outer annular plane and an inner, intermediate and outer tilting the swash surface. The inner inclined surface extends between the flat inner surface and the inner annular plane, the intermediate inclined surface extends between the inner annular plane and the outer annular plane, and the other inclined surface extends between the outer annular plane and the shower head Extend between the outer edges of the electrodes. The thickness of the multi-step showerhead electrode across the flat inner surface is smaller than the thickness of the multi-step showerhead electrode across the inner annular plane, and the thickness across the inner annular plane is smaller than the thickness across the outer annular plane.

FIG. 1 shows a partial cross-sectional view of an embodiment of a showerhead electrode assembly 100 of a plasma processing system for etching a substrate. As shown in FIG. 1, the showerhead electrode assembly 100 includes a showerhead electrode 110, a supporting plate 140, and a guard ring (or outer ring) 170. The showerhead electrode assembly 100 also includes a plasma surrounding beam ring assembly (or a wafer area pressure (WAP, wafer area pressure) assembly) 180 that surrounds the showerhead electrode 110 and the outer periphery of the support plate 140.

The assembly 100 also includes a thermal control plate 102 and an upper temperature control (top) plate 104 having a liquid flow channel therein and forming a temperature control wall of the chamber. The showerhead electrode 110 is preferably a circular plate, and may be coated with high-purity conductive materials (such as monocrystalline silicon, polycrystalline silicon, silicon carbide) or other suitable materials (such as aluminum or its alloys, electroplated aluminum, and yttrium oxide). Aluminum) manufactured. A temperature sensor 580 (FIG. 5) (such as a thermocouple, an optical fiber temperature sensor, or a resistance temperature detector) with an appropriate temperature range is set to directly contact the showerhead electrode 110. The support plate 140 is mechanically fixed to the shower head electrode 110 by the following mechanical fasteners. The protective ring 170 surrounds the support plate 140 and allows the cam lock member as described below to enter and exit. The temperature sensor 580 can output temperature data to the controller 581 for activating one or more heaters 582, which can adjust the temperature of the showerhead electrode.

The showerhead electrode assembly 100 shown in FIG. 1 can generally be used with an electrostatic chuck (not shown) combined with a flat bottom electrode. At a distance of about 1 to 2 cm below the showerhead electrode 110, the wafer is Supported on this lower electrode. An example of such a plasma processing system is a parallel plate reactor, such as the Exelan® dielectric etching system manufactured by Lam Research Corporation in Fremont, California, USA. Such a clamping device can provide temperature control of the wafer by supplying a backside helium (He) pressure for controlling the heat transfer rate between the wafer and the chuck.

The shower head electrode 110 is a consumable part and must be replaced regularly. In order to supply the processing gas to the gap between the wafer and the showerhead electrode 110, the showerhead electrode 110 may be provided with a gas outlet 106 having a size and distribution suitable for supplying the processing gas, which is excited by the electrode And a plasma is formed in the reaction zone under the shower head electrode 110.

The showerhead electrode assembly 100 also includes a plasma surrounding beam ring assembly (or wafer area pressure (WAP) assembly) 180, which surrounds the showerhead electrode 110 and the outer periphery of the support plate 140. The plasma enclosure assembly 180 is preferably composed of a plurality of spacer rings 190 or a stack thereof, which surrounds the outer periphery of the showerhead electrode 110 and the support plate 140. During the process, the plasma beam assembly 180 will cause a pressure difference in the reaction zone and increase the resistance between the wall of the reaction chamber and the plasma, thereby limiting the electrical flow between the showerhead electrode 110 and the lower electrode (not shown). Pulp.

During use, the confining ring 190 can confine the plasma to the chamber volume and control the plasma pressure in the reaction chamber. The plasma enclosure of the reaction chamber is a function of many factors, these factors include: the interval between the enclosure ring 190, the pressure of the reaction chamber and the plasma pressure outside the enclosure ring, the type and flow rate of the gas, and the RF power The level and frequency. If the interval between the confining rings 190 is very small, we can more easily achieve plasma confinement. Typically, the spacing required for the beam is 0.15 inches or less. However, the interval of the confining ring 190 also determines the pressure of the plasma, and we hope that while maintaining the plasma, the interval can be adjusted to achieve the pressure required for the best processing performance. The processing gas from the gas supply source can be supplied to the showerhead electrode 110 through one or more channels located in the upper temperature control plate 104. These channels can allow the processing gas to be supplied to a single area or multiple areas located above the wafer. area.

The showerhead electrode 110 is preferably a circular plate, which has a uniform thickness from the center (the left side of FIG. 1) to the thickened area, which is formed on the plasma exposed surface extending inward from the outer edge At least one step. The showerhead electrode 110 preferably has a larger diameter than the wafer to be processed, for example, 300 mm or more. In order to process 300 mm wafers, the diameter of the showerhead electrode 110 can range from about 15 inches to about 17 inches (as used herein, "about" refers to ±10%).

Monocrystalline silicon and polycrystalline silicon are preferred materials for the plasma exposed surface of the showerhead electrode 110. High-purity single crystal or polycrystalline silicon can minimize the substrate contamination during plasma processing, because it introduces only the smallest amount of unnecessary elements into the reaction chamber, and it wears smoothly during the plasma processing, thereby reducing the particle size least. Alternative materials containing composite materials that can be used for the plasma exposed surface of the showerhead electrode 110 may include, for example, aluminum (as used herein, "aluminum" refers to pure Al and its presence or electroless plating or other coatings). Surface alloy), polysilicon, yttrium oxide coated aluminum, SiC, SiN, and AlN.

The support plate 140 is preferably made of a material that is chemically compatible with the processing gas used for processing the semiconductor substrate in the plasma processing chamber; has a thermal expansion coefficient that closely matches the electrode material; and/or has electrical and thermal conductivity. Preferred materials that can be used to manufacture the support plate 140 include, but are not limited to, graphite, SiC, aluminum (Al), or other suitable materials.

The showerhead electrode 110 can be mechanically attached to the support plate 140 without any adhesive between the electrode and the support plate, that is, the electrode is attached to the support plate without using thermally conductive and elastic bonding materials.

The supporting plate 140 is preferably attached to the thermal control board 102 by a suitable mechanical fastener, and the fastener may be a threaded bolt, a screw, or the like. For example, a bolt (not shown) can be inserted into the hole of the thermal control plate 102 and screwed into the threaded opening of the support plate 140. The thermal control plate 102 includes a curved portion 184, and is preferably made of a processed metal material, such as aluminum or the like. The upper temperature control plate 104 is preferably made of aluminum. The plasma bundle assembly (or wafer area pressure (WAP) assembly) 180 is arranged outside the shower head electrode assembly 100. In the commonly owned US Patent No. 5,534,751, a suitable plasma confining assembly 180 including a plurality of vertically adjustable plasma confining rings 190 is described, the entire content of which is incorporated herein by reference.

The shower head electrode 110 can be obtained by, for example, the jointly owned PCT/US2009/001593 (which is claiming the priority of U.S. Application No. 61/036,862 (filed on March 14, 2008), and its disclosures are hereby incorporated into For reference) the cam lock mechanism described above is mechanically attached to the support plate 140. Referring to FIG. 2A, a perspective view of an exemplary cam lock electrode clamping device includes a part of the electrode 201 and a support plate 203. The electrode clamping device can quickly, neatly and accurately attach the consumable electrode 201 to the support plate in various tools related to the wafer manufacturing plant (such as the plasma etching chamber shown in FIG. 1).

The electrode clamping device includes a screw pile (locking pin) 205 installed in a socket 213. This stud can be surrounded by a disc spring stack 215 such as a stainless steel Belleville washer. Therefore, the pile 205 and the disc spring stack 215 can be press-fitted into the socket 213 or buckled into the socket 213 in other ways through the use of adhesives or mechanical fasteners. The screw pile 205 and the disc-shaped spring stack 215 are arranged in the socket 213 so that a limited amount of lateral movement can exist between the electrode 201 and the support plate 203. Limiting the amount of lateral movement can provide a close fit between the electrode 201 and the support plate 203, thus ensuring good thermal contact, while still providing some movement to deal with the difference in thermal expansion between the two parts. Below, additional details of the limited lateral movement feature will be discussed in more detail.

In a specific exemplary embodiment, the socket 213 is made of Torlon® bearing grade. Alternatively, the socket 213 can be made of other materials with certain mechanical properties such as good strength and impact resistance, and can also easily utilize creep resistance, dimensional stability, radiation resistance, and chemical resistance. sex. Various materials such as polyamide, polyimide, acetal, and ultra-high molecular weight polyethylene materials are applicable. Because the typical maximum temperature encountered in applications (such as etching chambers) is 230° C., high-temperature special plastics and other related materials are not required to form the socket 213. Generally speaking, the typical operating temperature is closer to 130°C.

The other part of the electrode clamping device is composed of a camshaft 207, and each end of the camshaft is surrounded by a pair of camshaft bearings 209. The camshaft 207 and the camshaft bearing assembly are installed in the support plate hole 211 machined into the support plate 203. In a typical application for an etching chamber designed for a 300 mm semiconductor wafer, more than 8 electrode clamping devices can be installed at intervals around the periphery of the electrode 201/support plate 203 combination.

The camshaft bearing 209 can be processed from various materials, including Torlon®, Vespel®, Celcon®, Delrin®, Teflon®, Arlon®, or, for example, fluoropolymers with low friction coefficient and low particle shedding, Acetal, polyamide, polyimide, polytetrafluoroethylene, and other materials such as polyetheretherketones (PEEK). The bolt 205 and the camshaft 207 can be made of stainless steel (such as 316, 316L, 17-7, etc.) or any other material that can provide good strength and corrosion resistance.

2B, the cross-sectional view of the electrode cam clamping device further illustrates how the cam clamping device operates by pulling the electrode 201 closer to the support plate 203. The screw pile 205/disc spring stack 215/bearing seat 213 assembly is installed in the electrode 201. As shown, this component can be screwed into the threaded cavity of the electrode 201 by the external thread on the socket 213. However, we can use adhesives or other types of mechanical fasteners to install this component.

In FIG. 3, the side view and assembly view 300 of the screw pile 205 with the enlarged head, the disc spring stack 215, and the socket 213 can provide additional details for the exemplary design of the cam lock electrode clamping device. In a specific exemplary embodiment, the bolt/disc spring assembly 301 is press-fitted into the socket 213. The socket 213 has external threads and a hexagonal top member, which allows the electrode 201 (see FIGS. 2A and 2B) to be easily inserted into the electrode 201 (see FIGS. 2A and 2B) with a small amount of torque (for example, about 20 inch-pounds in a specific exemplary embodiment). As mentioned above, the socket 213 can be processed from various plastics. The use of plastic can minimize particle generation and allow the socket 213 to be installed in the mating cavity on the electrode 201 in a gall-free manner.

The screw pile/bearing seat assembly 303 shows that the inner diameter of the upper part of the bearing 213 is greater than the outer diameter of the middle part of the screw pile 205. The difference in diameter between the two parts can allow limited lateral movement in the assembled electrode clamping device as described above. At the bottom of the bearing seat 213, the bolt/disc spring assembly 301 maintains firm contact with the bearing seat 213, and the diameter difference allows some lateral movement (see also FIG. 2B).

Referring to FIG. 4A, an exploded view 400 of the camshaft 207 and the camshaft bearing 209 also shows a keying pin 401. First, insert the end of the camshaft 207 with the keying pin 401 into the support plate hole 211 (see FIG. 2B). A pair of tiny matching holes (not shown) located at the distal end of the support plate hole 211 can provide proper alignment of the camshaft 207 in the support plate hole 211. The side view 420 of the camshaft 207 clearly shows the possible configuration of the hexagonal opening 403 on one end of the camshaft 207 and the keying pin 401 on the opposite end.

For example, continuing to refer to FIGS. 4A and 2B, we can assemble the electrode cam clamping device by inserting the camshaft 207 into the support plate hole 211. The keying pin 401 can be engaged with one of the pair of tiny matching holes to limit the rotation distance of the camshaft 207 in the support plate hole 211. The camshaft can first rotate in a counterclockwise direction through the use of the hexagonal opening 403 to allow the bolt 205 to enter the camshaft 207, and then rotate clockwise to fully engage and lock the bolt 205. The clamping force required to fix the electrode 201 to the support plate 203 can be supplied by compressing the disc spring stack 215 beyond its free stack height. The camshaft 207 has an inner eccentric cutout, which can be engaged with the enlarged head of the bolt 205. When the disc-shaped spring stack 215 is compressed, the clamping force can be transmitted from the individual springs in the disc-shaped spring stack 215 to the holder 213 and reach the support plate 203 through the electrode 201.

In an exemplary mode of operation, once the camshaft bearing is attached to the camshaft 207 and inserted into the support plate hole 211, the camshaft 207 can be rotated counterclockwise to its maximum rotation distance, so the bolt/bearing assembly 303 (Figure 3) It can be gently twisted into the electrode 201, and then the head of the screw pile 205 is inserted into the vertically extending hole under the horizontally extending support plate hole 211. The electrode 201 is fixed against the support plate 203, and the camshaft 207 is rotated clockwise until the keying pin falls into the second of the two tiny matching holes (not shown) or a sound is heard (details will be described below) )until. This exemplary mode of operation can be reversed to remove the electrode 201 from the support plate 203. However, in this cam lock device, features such as sound are not essential.

4B, the side view 420 of the camshaft 207 in FIG. 4A shows a cutting path edge (cutter path edge) 440 in a cross-sectional view taken along the AA line. By this cutting path edge, the head of the bolt 205 can be Is completely fixed. In a specific exemplary embodiment, two radii R are selected₁With R₂, So that the head of the screw pile 205 emits the above-mentioned unnecessary sound to indicate when the screw pile 205 is completely fixed.

FIG. 5 shows a showerhead electrode assembly 500 for a capacitively coupled plasma chamber, which includes the following features: (a) a non-engaged cam-locked showerhead electrode 502; (b) a support plate 506; and (c) a guard ring 508, which can provide a cam lock for fixing the electrode to the support plate 506 in and out.

The electrode assembly 500 includes a thermal control plate 510, which is bolted from the outside of the chamber to the temperature control top wall 512 of the chamber, and has an annular protrusion on the bottom surface, which is used to define and support the plate The gas filling part connected to the gas channel. The showerhead electrode 502 is detachably attached to the support plate 506 from the inside of the chamber by the cam lock mechanism 514 described above with reference to FIGS. 2-4.

In a preferred embodiment, the shower head electrode 502 of the electrode assembly 500 can be disassembled by the following methods: (a) Rotate the guard ring 508 to the first position, which is the four holes in the guard ring Align with the four cam locks 514 at the spaced positions in the outer part of the support plate 506; (b) insert a tool such as an allen wrench to pass through each hole of the protective ring 508, And turn each cam lock 514 to remove the vertically extending locking pin 562 of each cam lock 514; (c) Rotate the protection ring 508 by 90° to reach the second position, which is four of the protection rings 508 The hole is aligned with the other four cam locks 514; and (d) Insert a tool such as a hexagon wrench through each hole of the protective ring 508, and turn each cam lock 514 to remove each cam lock 514 The locking pin 562; thereby lowering the shower head electrode 502 and removing it from the plasma chamber.

FIG. 5 also shows a cross-sectional view of one of the cam lock devices, in which the rotatable cam lock 514 is located in the horizontally extending hole 560 outside the support plate 506. The cylindrical cam lock 514 can be rotated by a tool such as a hexagonal wrench to: (a) a locking position, in which the enlarged end of the locking pin 562 can be engaged with the cam surface of the cam lock 514, and the cam surface can be lifted The enlarged head of the locking pin; or (b) a removal position in which the locking pin 562 is not engaged with the cam lock 514. The support plate 506 includes vertically extending holes on its bottom surface, and the locking pin 562 can be inserted through these holes and engage with the cam lock 514.

The showerhead electrode 502 is preferably a single crystal silicon plate with high purity (less than 10 ppm impurities) and low resistivity (0.005 to 0.02 ohm-cm). The showerhead electrode assembly 500 includes: three alignment pins 524 engaged in the three alignment pin holes 521 on the top surface 522 of the showerhead electrode 502; one or more O-rings 558 and, for example, Q-washers (Q -Pads) 556 thermal washers, located between the shower head electrode 502 and the support plate 506. Each Q-washer 556 has a convex portion, and the convex portion can be engaged with the groove 520 of the top surface 522. The details of this gasket are disclosed in the jointly owned US application No. 12/421,845 (application dated April 10, 2009, the disclosure of which is hereby incorporated by reference). The plasma exposed surface 530 on the showerhead electrode 502 faces the substrate being processed in the chamber.

6A and 6C show the mounting surface of the showerhead electrode 502 and a partial cross-sectional view. The mounting surface has a flat surface 610 extending close to the outer edge and a narrow annular outer protrusion 620 recessed from the flat surface 610 and located at the outer edge of the showerhead electrode 502. The annular outer protrusion 620 can support the annular protrusion of the protection ring 508. The flat surface 610 has an outer diameter of about 16.75 inches. The annular outer protrusion 620 has an inner diameter of about 16.75 inches, an outer diameter of about 17 inches, a vertical surface 620a of about 0.076 inches long, and a horizontal surface 620b of about 0.124 inches. Eight cavities 550 with a depth of 0.325 inches and a diameter of 0.5 inches are arranged close to the edge of the mounting surface to accommodate the locking pin 562. The pockets 550 are equidistant from each other and are located on a radius of about 7.62 inches from the center.

The plane 610 includes: 3 alignment pin holes 521 with a diameter of 0.116 inches, which have a depth of about 0.2 inches and are located at a distance of about 7.93 inches from the center; and 7 grooves 520 with a diameter of 0.215 inches, which have a diameter of about 0.04 inches Depth, and used to accommodate the protrusions on the 3 Q-shims 556. The two grooves 520 are located at a distance of about 1.59 inches from the center and are offset from each other by 180° in azimuth. The other two grooves 520 are located at a distance of about 3.39 inches from the center and are offset from each other by 180° in azimuth. The other three grooves 520 are located at a distance of about 7.30 inches from the center and are offset from each other by 120° in azimuth.

The plane 610 further includes a hole 590 for accommodating the temperature sensor 580, and the hole 590 is located at a distance of about 4.83 inches from the center. In a preferred embodiment as shown in FIG. 6D, the hole 590 has a depth of at most 0.08 inches; the hole 590 includes a cylindrical side surface 590a located at the bottom of the hole 590 and having a diameter of at most 0.029 inches and a height of about 0.0035 inches, and The frusto-conical side surface 590b with a circular bottom of about 0.153 inches in diameter and an opening angle of about 90° extends between the cylindrical side surface and the mounting surface. The temperature sensor (thermocouple) extending through the openings in the top plate, the thermal control plate and the support plate may include a tip spring biased in the bottom 590a of the hole 590. The conical surface 590 b can align the tip of the sensor 580 with the center of the bottom of the hole 590.

The gas outlet 528 may extend from the mounting surface to the plasma exposure surface, and may be arranged in any suitable pattern. In the embodiment shown, 849 gas outlets 528 with a diameter of 0.017 inches can be arranged in a pattern of a central gas outlet and 13 circumferentially extending gas outlet rows. In this gas outlet row, the first row There are 10 gas outlets and the distance from the center of the electrode is about 0.5 inches, the second row has 18 gas outlets and the distance from the center is about 0.9 inches, the third row has 28 gas outlets and the distance is about 1.4 inches from the center, and the fourth row has 38 The gas outlet is about 1.8 inches from the center, the fifth row has 46 gas outlets and the distance is about 2.3 inches from the center, the sixth row has 56 gas outlets and the distance from the center is about 2.7 inches, the seventh row has 66 gas outlets and the distance from the center About 3.2 inches, the eighth row has 74 gas outlets and the distance from the center is about 3.6 inches, the ninth row has 84 gas outlets and the distance from the center is about 4.1 inches, and the tenth row has 94 gas outlets and the distance from the center is about 4.6 inches. The eleventh row has 104 gas outlets and the distance from the center is about 5.1 inches, the twelfth row has 110 gas outlets and the distance from the center is about 5.4 inches, and the thirteenth row has 120 gas outlets and the distance from the center is about 5.7 inches.

As shown in FIG. 6C, the single-step showerhead electrode 502 has a plasma exposed surface, which includes a circular inner surface 640 with a diameter of about 12 inches, and a ring-shaped outer surface with an inner diameter of about 12.55 inches and an outer diameter of about 16 inches. The surface 650, the inner inclined surface 645 extending between the circular inner surface 640 and the annular outer surface 650 at an angle of about 145° with respect to the surface 640, and the annular outer surface 650 and the cylindrical shape of the showerhead electrode 502 The outer inclined surface 635 extends between the peripheral surfaces 630 at an angle of about 155° with respect to the surface 650. The thickness between the annular outer surface 650 and the surface 610 is about 0.44 inches. The thickness between the circular inner surface 640 and the surface 610 is about 0.26 inches.

The multi-step showerhead electrode 502 is shown in FIG. 6E, where the plasma exposed surface includes a circular inner surface 640 with a diameter of about 12 inches, an inner ring surface with an inner diameter of about 12.2 inches and an outer diameter of about 13.2 inches. 660. An outer annular surface 670 having an inner diameter of about 13.4 inches and an outer diameter of about 16 inches, and an inner inclined surface extending between the circular inner surface 640 and the inner annular surface 660 at an angle of about 145° with respect to the surface 640 646. A middle inclined surface 667 extending between the inner annular surface 660 and the outer annular surface 670 at an angle of about 135° with respect to the surface 670, and the cylindrical peripheral surface 630 between the outer annular surface 670 and the showerhead electrode The outer inclined surface 637 extends at an angle of about 155° with respect to the surface 670 therebetween. The thickness between the outer annular surface 670 and the surface 610 is about 0.44 inches. The thickness between the inner annular surface 660 and the surface 610 is about 0.36 inches. The thickness between the circular inner surface 640 and the surface 610 is about 0.26 inches.

In yet another embodiment of the multi-step showerhead electrode 502, the cross section is shown in FIG. 6F. The plasma exposed surface includes a circular inner surface 640 with a diameter of about 12 inches and an inner diameter of about 12.4 inches. An inner annular surface 680 with an outer diameter of about 13.3 inches, an outer annular surface 690 with an inner diameter of about 13.4 inches and an outer diameter of about 16 inches, between the circular inner surface 640 and the inner annular surface 680 to be opposite to the surface 640, an inner inclined surface 648 extending at an angle of about 145°, an intermediate inclined surface 689 extending at an angle of about 135° with respect to the surface 690 between the inner annular surface 680 and the outer annular surface 690, and an outer annular surface An outer inclined surface 639 extending between the surface 690 and the cylindrical peripheral surface 630 of the showerhead electrode 502 at an angle of about 155° with respect to the surface 690. The thickness between the outer annular surface 690 and the surface 610 is about 0.44 inches. The thickness between the inner annular surface 680 and the surface 610 is about 0.40 inches. The thickness between the circular inner surface 640 and the surface 610 is about 0.26 inches.

FIG. 7 is a perspective view of the supporting plate 506. The supporting plate 506 includes a central gas channel aligned with the outlet 528 of the shower head electrode 502 and 13 gas channel rows 584. The top surface 586 of the support plate includes three ring-shaped areas 588a, 588b, and 588c, and these ring-shaped areas are in contact with the ring-shaped protrusions of the thermal control plate 510. The thermal control panel can be attached to the top wall of the plasma chamber by fasteners. These fasteners extending through the top wall and into the thermal control panel are similar to those of US Patent Publication No. 2005 /0133160, No. 2007/0068629, No. 2007/0187038, No. 2008/0087641, and No. 2008/0090417, the disclosures are hereby incorporated by reference. The threaded opening 599 is located in the outer periphery of the top surface 586 and the annular areas 588a, 588b, 588c to accommodate the fasteners extending through the openings in the top plate 512 and the thermal control plate 510, and the supporting plate 506 is fixed and used It is in contact with the thermal control board 510. For example, refer to the description of the fastener in Jointly Granted U.S. Patent Publication No. 2008/0087641, which can adapt to thermal cycling. The groove 592 on the top surface 586 can accommodate an O-ring, which can provide a gas seal between the support plate 506 and the thermal control plate 510. The alignment pin hole 594 on the top surface 586 can accommodate the alignment pin, which can be installed in the alignment pin hole of the thermal control board. The horizontally extending threaded opening 561 located between the holes 560 can accommodate a dielectric fastener, which can prevent the protection ring 508 from rotating and can plug the protection ring 508 after assembling the showerhead electrode 502 Manhole in the middle.

FIG. 8 is a perspective view of the showerhead electrode assembly 500 with the guard ring 508 removed. As described above, the protective ring 508 can be rotated to more than one assembly position and a locking position. In this assembly position, the cam lock 514 can be engaged. In this locking position, the dielectric fastener can be inserted into the opening 561. In order to keep the guard ring out of contact with the outer periphery of the support plate, the thermal expansion of the support plate can be allowed. The thermal control plate includes a flange 595 with openings 596 through which the driving device can support the plasma enclosure ring. The details of the installation device of the plasma confining ring assembly can be found in the joint grant of US Patent Publication Nos. 2006/0207502 and 2006/0283552, and the disclosures are hereby incorporated by reference.

The mounting surface 610 of the showerhead electrode will abut the opposite surface of the support plate 506 due to the clamping force exerted by the eight locking pins, which are fixed by the eight cam locks in the support plate. The protective ring 508 can cover the mounting hole on the support plate 506, and the access opening in the protective ring can be filled with a removable insert made of a plasma-resistant polymer material, such as Torlon®, Vespel®, Celcon® , Delrin®, Teflon®, Arlon®, or, for example, fluoropolymers, acetals, polyamides, polyimines, polytetrafluoroethylene, and polyether ether ketone (PEEK) with low friction coefficient and low particle detachment Other materials.

5, the electrical and thermal contact between the support plate 506 and the showerhead electrode 502 can be provided by a gasket such as Q-gasket 556, which is located on the outer periphery of the electrode and on the outer periphery of the electrode. One or more positions inside the outer Q-gasket. For example, Q-shims having diameters of approximately 3.2, 6.8, and 12 inches can be used. The co-owned US application No. 11/896,375 (application dated August 31, 2007) contains the details of the Q-gasket, and its disclosure is hereby incorporated by reference. In order to provide different processing gas mixtures and/or flow rates, more than one optional gas partition seals can be provided across the top surface of the electrode. For example, between the showerhead electrode 502 and the support plate 506, a single O-ring can be placed at a position between the inner and outer Q-gaskets to separate the inner gas distribution area from the outer gas distribution area . An O-ring 558 located between the showerhead electrode 502 and the support plate 506 and along the inner periphery of the outer Q-gasket can provide a gas and particle seal between the electrode and the support plate.

Although this creation has been described in detail with reference to its specific embodiments, those who are familiar with this technique can understand that various changes and modifications can be made without departing from the scope of the appended claims, and equivalents can be used instead.

<p>100Spray head electrode assembly</p><p>102Thermal control board</p><p>104Upper temperature control board</p><p>106Gas outlet</p><p>110Spray head electrode</p><p>140Support plate</p><p>170Protection Ring</p><p>180Plasma surrounding beam ring assembly</p><p>184Bending part</p><p>190Enclosure ring</p><p>201electrode</p><p>203Support plate</p><p>205Screw pile</p><p>207Camshaft</p><p>209Camshaft bearing</p><p>211Support plate hole</p><p>213Seat</p><p>215Disc spring stack</p><p>300Side view and assembly view</p><p>301Screw pile/disc spring assembly</p><p>303Screw pile/bearing assembly</p><p>400Exploded view</p><p>401Keying pin</p><p>403Hexagonal opening</p><p>420Side view</p><p>440Cutting path edge</p><p>500Spray head electrode assembly</p><p>502Spray head electrode</p><p>506Support plate</p><p>508Protection Ring</p><p>510Thermal control board</p><p>512Top plate</p><p>514Cam lock</p><p>520Groove</p><p>521Aligning pin hole</p><p>522Top surface</p><p>524Alignment pin</p><p>528Gas outlet</p><p>530Plasma exposed surface</p><p>550Cavity</p><p>556Q-Gasket</p><p>558O-ring</p><p>560Horizontal extension hole</p><p>561Open</p><p>562Locking pin</p><p>580Temperature sensor</p><p>581controller</p><p>582Heater</p><p>584Gas channel row</p><p>586Top surface</p><p>588aAnnular area</p><p>588bAnnular area</p><p>588cAnnular area</p><p>590Hole</p><p>590aCylindrical side surface</p><p>590bTruncated cone-shaped side surface</p><p>592Groove</p><p>594Aligning pin hole</p><p>595Flange</p><p>596Open</p><p>599Threaded opening</p><p>610Mounting surface</p><p>620Annular outer protrusion</p><p>620aVertical surface</p><p>620bHorizontal surface</p><p>630Cylindrical peripheral surface</p><p>635Outer inclined surface</p><p>637Outer inclined surface</p><p>639Outer inclined surface</p><p>640Circular inner surface</p><p>645Internally inclined surface</p><p>646Inner inclined surface</p><p>648Internally inclined surface</p><p>650Annular outer surface</p><p>660Inner ring surface</p><p>667Intermediate inclined surface</p><p>670Outer annular surface</p><p>680Inner ring surface</p><p>689Intermediate inclined surface</p><p>690Outer annular surface</p>

Figure 1 shows a partial cross-sectional view of the showerhead electrode assembly.

2A is a perspective view of an exemplary cam lock used to clamp the shower head electrode in the reactor shown in FIG. 1.

2B is a cross-sectional view of the exemplary cam lock electrode clamping device of FIG. 2A.

Fig. 3 shows a side view and assembly view of an exemplary locking pin used in the cam lock clamping device of Figs. 2A and 2B.

Fig. 4A shows a side view and assembly view of an exemplary camshaft used in the cam lock clamping device of Figs. 2A and 2B.

Fig. 4B shows a cross-sectional view of an exemplary cutting path edge of a part of the camshaft of Fig. 4A.

Figure 5 shows a showerhead electrode assembly with a showerhead electrode, a support plate, a thermal control board, a guard ring, and a top plate.

Fig. 6A is a top view of the shower head electrode.

6B is a cross-sectional view of a showerhead electrode according to an embodiment of the showerhead electrode.

Fig. 6C is an enlarged view of part C of Fig. 6B.

Figure 6D is a partial cross-sectional view of the showerhead electrode passing through the groove for accommodating the temperature sensor.

Fig. 6E is a partial cross-sectional view of another embodiment of the showerhead electrode.

Fig. 6F is a partial cross-sectional view of yet another embodiment of the showerhead electrode.

FIG. 7 is a perspective view of the support plate shown in FIG. 5, in which the gas channel pattern and the alignment pin hole pattern shown are not accurate.

FIG. 8 is a perspective view of the showerhead electrode assembly without a protective ring, in which the gas channel pattern shown is not accurate.