Inorganic coating of plasma chamber components

Abstract

We provide components for use in plasma processing chambers. [Solution] The component body is made of a conductive material. A first ceramic coating made of a first ceramic material is present on the surface of the component body, and the first ceramic coating has a first side adjacent to the component body and a second side away from the component body, and the first ceramic material is a dielectric material. A second ceramic coating made of a second ceramic material is present on the second side of the first ceramic coating, and there is a gap between the first ceramic coating and the second ceramic coating, which is filled with at least one of a polymer material or a gas, and the second ceramic material is a dielectric material.

Description

Technical Field

[0001] <Cross - Reference to Related Applications> This application claims the benefit of priority of U.S. Patent Application No. 62 / 913,619, filed on October 10, 2019, which is hereby incorporated by reference in its entirety for all purposes.

[0002] This disclosure relates to the manufacture of semiconductor devices. More specifically, this disclosure relates to the coating of chamber surfaces used in the manufacture of semiconductor devices.

Background Art

[0003] The background description provided herein is for the purpose of generally presenting the content of the present disclosure. All descriptions in this background art section, and aspects that may exist in the described descriptions, whether explicitly or implicitly, are not admitted as prior art with respect to the present application.

[0004] When processing a semiconductor wafer, a plasma processing chamber is used to process the semiconductor device. A coating is used to protect the chamber surface.

[0005] In the formation of semiconductor devices, a substrate is processed using a plasma processing chamber. Some plasma processing chambers have components of an aluminum alloy, such as in a liner within the plasma processing chamber. Such components may be aluminum to provide electrical and thermal properties useful for maintaining the plasma. Aluminum also allows for weight and cost reduction. Such aluminum components may be corroded by the plasma used during plasma processing. A coating may be used to protect the aluminum components.

[0006] To protect against plasma corrosion, a ceramic coating is formed on the components of the plasma processing chamber. Such coatings are subjected to stress due to mismatches in thermal expansion coefficients and fluorination due to exposure to fluorine plasma, which can result in component failure or the generation of contaminants from the components. Generally, the thermal expansion coefficient (CTE) of aluminum ESC bodies is greater than that of ceramic protective coatings. The difference in CTE between the ESC body and the protective coating can cause cracking in the protective coating. [Overview of the Initiative]

[0007] To solve the aforementioned problems and in accordance with the purposes of this disclosure, a component for use in a plasma processing chamber is provided. The component body is made of a conductive material. A first ceramic coating made of a first ceramic material is provided on the surface of the component body, the first ceramic coating having a first side adjacent to the component body and a second side away from the component body, the first ceramic material being a dielectric material. A second ceramic coating made of a second ceramic material is provided on the second side of the first ceramic coating, with a gap between the first and second ceramic coatings, the gap being filled with at least one of a polymer material or a gas, the second ceramic material being a dielectric material.

[0008] In another embodiment, a method is provided for coating a component body for use in a plasma processing chamber. A first ceramic coating is formed on the surface of the component body, the first ceramic coating having a first side adjacent to the component body and a second side away from the component body, the component body being made of a conductive material and the first ceramic coating being made of a dielectric material. A polymer layer is formed on the second side of the first ceramic coating, the polymer layer having a first side adjacent to the second side of the first ceramic coating and a second side away from the first ceramic coating. A second ceramic coating is formed on the second side of the polymer layer, the second ceramic coating being made of a dielectric material.

[0009] In another embodiment, a method is provided for coating a component body for use in a plasma processing chamber. A ceramic coating is formed on the surface of the component body, the component body being made of a conductive material and the ceramic coating being made of a dielectric material. An ion exchange process forms a compression layer in the ceramic coating.

[0010] In another embodiment, a component for use in a plasma processing chamber is provided. The component body is made of a conductive material. A diamond-like carbon coating is present on the surface of the component. A ceramic coating is present on top of the diamond-like carbon coating.

[0011] In another embodiment, a method is provided for coating a component body for use in a plasma processing chamber. A diamond-like carbon coating is formed on the surface of the component body, which is made of a conductive material. A ceramic coating is deposited on top of the diamond-like carbon coating.

[0012] In another embodiment, a method is provided for coating a component body for use in a plasma processing chamber. The metal oxide coating is deposited on the component body by performing at least one of metal oxide chemical vapor deposition or plasma-excited vapor deposition at a temperature below 300°C.

[0013] These and other features of the Disclosure will be described in more detail below in conjunction with the detailed description of the Disclosure and the drawings below. [Brief explanation of the drawing]

[0014] The present disclosure is illustrated by the following accompanying drawings, which are provided for illustrative purposes only, not for limitation. Similar reference numerals in the drawings refer to similar elements.

[0015] [Figure 1] Figure 1 is a high-level flowchart of an embodiment.

[0016] [Figure 2A] Figure 2A is a schematic diagram of a substrate processed according to the embodiment shown in Figure 1. [Figure 2B] Figure 2B is a schematic diagram of a substrate processed according to the embodiment shown in Figure 1. [Figure 2C] Figure 2C is a schematic diagram of a substrate processed according to the embodiment shown in Figure 1. [Figure 2D] Figure 2D is a schematic diagram of a substrate processed according to the embodiment shown in Figure 1.

[0017] [Figure 3] Figure 3 is a schematic diagram of a plasma processing system that may be used in the embodiment.

[0018] [Figure 4] Figure 4 is a high-level flowchart of another embodiment.

[0019] [Figure 5A]FIG. 5A is a schematic view of a substrate processed according to the embodiment shown in FIG. 4. [Figure 5B] FIG. 5B is a schematic view of a substrate processed according to the embodiment shown in FIG. 4.

[0020] [Figure 6] FIG. 6 is a high-level flowchart of another embodiment.

[0021] [Figure 7A] FIG. 7A is a schematic view of a substrate processed according to the embodiment shown in FIG. 6. [Figure 7B] FIG. 7B is a schematic view of a substrate processed according to the embodiment shown in FIG. 6.

[0022] [Figure 8] FIG. 8 is a high-level flowchart of another embodiment.

[0023] [Figure 9] FIG. 9 is a schematic view of a substrate processed according to the embodiment shown in FIG. 8. DETAILED DESCRIPTION OF THE INVENTION

[0024] The present disclosure will be described in detail with reference to several preferred embodiments shown in the accompanying drawings. In the following description, many specific details are set forth in order to provide a thorough understanding of the present disclosure. However, it will be apparent to those skilled in the art that the present disclosure may be practiced without some or all of these specific details. In other instances, well-known process steps and / or structures have not been described in detail in order not to obscure the present disclosure unnecessarily.

[0025] In electrostatic chucks (ESCs) within a plasma processing chamber, corrosion of the ESC can be induced by the plasma conditions. A protective coating can be applied to the surface of the ESC. Typically, aluminum ESCs have a higher coefficient of thermal expansion (CTE) than ceramic protective coatings. This difference in CTE between the ESC and the protective coating can cause cracking in the coating.

[0026] Several embodiments are provided to provide an improved protective coating. To facilitate understanding of the embodiments, Figure 1 shows a high-level flowchart of the process used in an embodiment for coating a component body. The component body is installed (step 104). In this example, the component body is made of a conductive material, such as aluminum with an anodized surface. A first ceramic coating made of a ceramic material is applied to the surface of the component body (step 108). Figure 2A is a partial schematic cross-sectional view of the component body 204 having the first ceramic coating 208 on its surface. In this embodiment, the first ceramic coating 208 is deposited by thermal spray deposition. In other embodiments, the first ceramic coating may be deposited by plasma vapor deposition (PVD), chemical vapor deposition (CVD), or aerosol deposition. In this embodiment, the ceramic material is yttria. The component body 204 is on the first side of the first ceramic coating 208.

[0027] Thermal spraying is a general term used to describe various coating processes such as plasma spraying, arc spraying, flame / combustion spraying, and suspension spraying. All thermal spraying uses energy to heat a solid, bringing it to a molten or plasticized state. The molten or plasticized material is accelerated toward the substrate to coat its surface, and then cooled. These processes differ from vapor deposition processes, which use vaporized material instead of molten material. In this embodiment, the thickness of the ceramic coating is 25 to 500 microns. The first ceramic coating has a porosity in the range of 0.5% to 20%. In this specification and in the claims, the porosity is measured according to the standard test method ASTM E2109-01 (2014).

[0028] A polymer layer made of polymer material is deposited on the first ceramic coating 208. The polymer can be deposited by at least one of atomic layer deposition (ALD), chemical vapor deposition (CVD), plasma vapor deposition (PVD), plasma excited vapor deposition (PEVD), spin-on process, or other polymer deposition methods. Figure 2B is a partial schematic cross-sectional view of the component body 204 having the first ceramic coating 208 after the polymer layer 212 has been deposited. In this embodiment, the polymer layer 212 is formed from parylene. In this embodiment, the polymer layer 212 has a thickness of 25 to 500 microns.

[0029] A second ceramic coating made of a ceramic material is deposited on the polymer layer 212 (step 116). In this embodiment, the second ceramic coating is deposited by chemical vapor deposition (CVD). In other embodiments, the second ceramic coating may be deposited by plasma vapor deposition (PVD) or aerosol deposition. In this embodiment, the ceramic material is yttria. In this embodiment, the thickness of the second ceramic coating is 25 to 500 microns. The second ceramic coating has a porosity of less than 0.5%.

[0030] Figure 2C is a schematic cross-sectional view of a portion of the component body 204 after the deposition of the second ceramic coating 216 (step 116). In this example, the second ceramic coating 216 surrounds the polymer layer 212 and extends to the first ceramic coating 208.

[0031] The polymer layer 212 is removed (step 120). In this embodiment, a combustion gas containing oxygen is provided. The combustion gas is converted into a plasma. The plasma burns to remove the polymer layer 212, leaving a void. Figure 2D is a schematic cross-sectional view of a portion of the component body 204 with the void 220 remaining after the polymer layer 212 has been burned (step 120). In other embodiments, the polymer layer 212 is melted.

[0032] The component is mounted as part of the plasma processing chamber (step 124). In this embodiment, the component is an electrostatic chuck (ESC). Figure 3 is a schematic diagram of a plasma processing chamber 300 for plasma processing a substrate, in which the component may be installed in an embodiment. In one or more embodiments, the plasma processing chamber 300 includes a gas distribution plate 306 with a gas inlet and an ESC component 316 within a plasma processing chamber 304 enclosed by chamber walls 350. Within the plasma processing chamber 304, the substrate 307 is placed on the upper surface of the ESC component 316. The ESC component 316 may be supplied with bias from an ESC power supply 348. A gas source 310 is connected to the plasma processing chamber 304 via the gas distribution plate 306. An ESC temperature controller 351 is connected to the ESC component 316 to control the temperature of the ESC component 316. A radio frequency (RF) power supply 330 provides RF power to the ESC component 316 and the upper electrode. In this embodiment, the upper electrode is the gas distribution plate 306. In a preferred embodiment, power supplies of 400 kHz, 13.56 MHz, 1 MHz, 2 MHz, 60 MHz, and / or optionally 27 MHz constitute the RF power supply 330 and the ESC power supply 348. A controller 335 is controllably connected to the RF power supply 330, the ESC power supply 348, the exhaust pump 320, and the gas source 310. A high-flow liner 360 is a liner within the plasma processing chamber 304, having a groove 362 that confines gas from the gas source. The groove 362 maintains a controlled gas flow rate that allows gas to pass from the gas source 310 to the exhaust pump 320. An example of such a plasma processing chamber is the Flex® etching system from Lam Research Corporation (Fremont, CA). In various embodiments, the processing chamber may be a CCP (capacitance-coupled plasma) reactor or an ICP (inductively coupled plasma) reactor.

[0033] The plasma treatment chamber 304 plasma-treats the substrate 307 using the ESC component 316 (step 128). The plasma treatment may be etching, deposition, passivation, or one or more of other plasma treatments. The plasma treatment may be performed in combination with a non-plasma treatment. In such a treatment, the ESC component 316 may be exposed to a plasma containing halogens and / or oxygen.

[0034] Various components of the plasma processing chamber 304 utilize conductive metal substrates coated with dielectric materials such as aluminum oxide or yttrium oxide, deposited by thermal spraying or plasma atomization processes. Such components include ESC's pinnacle® and liner, as well as the gas distribution plate 306.

[0035] The absence of defects in the dielectric coating is crucial for maintaining both electrical standoff and chemical resistance. Thicker dielectric ceramic coatings are more prone to cracking. Thinner dielectric ceramic coatings do not provide sufficient insulation to prevent damage caused by the voltage used by the plasma processing chamber 304. Using two thin ceramic coatings, a first ceramic coating 208 and a second ceramic coating 216, reduces cracking compared to a thicker ceramic coating. Furthermore, the gap 220 provides higher dielectric strength between the first ceramic coating 208 and the second ceramic coating 216, increasing the standoff voltage and reducing electrical damage.

[0036] In other embodiments, after removing the polymer layer 212, the first ceramic coating 208 and the second ceramic coating 216 can be separated using walls, plugs, or pillars. In other embodiments, the gap 220 can be created by installing a support using other methods. For example, the ring may be placed on the first ceramic coating before the polymer layer fills the ring with polymer. The gap 220 may be filled with air to act as an air gap.

[0037] In other embodiments, the polymer layer 212 does not burn away. The polymer layer 212 has a higher dielectric strength than the first ceramic coating 208 and the second ceramic coating 216. However, the polymer layer 212 is rapidly corroded by the plasma. Therefore, the second ceramic coating 216 covers the polymer layer and protects it from the plasma. Such embodiments may provide improved standoff voltage and improved thermal insulation.

[0038] In various embodiments, the first ceramic coating 208 and the second ceramic coating 216 may be formed from alumina, yttria, zirconia, stabilized zirconia, yttrium-aluminum mixtures (such as yttrium aluminum garnet), or magnesium aluminum oxide (MgAl2O4) spinel. In other embodiments, the first ceramic coating 208 and the second ceramic coating 216 may be formed from rare earth materials such as erbium oxide, dysprosium oxide, cerium oxide, gadolinium oxide, and ytterbium oxide. In some embodiments, the first ceramic coating 208 is made of the same material as the second ceramic coating 216. When the first ceramic coating 208 and the second ceramic coating 216 are made of the same material, the first ceramic coating 208 and the second ceramic coating have the same CTE.

[0039] Figure 4 is a high-level flowchart of another embodiment. The component body is installed (step 404). The component body is made from a conductive material. The ceramic coating is deposited on the surface of the component body (step 408). Figure 5A is a schematic cross-sectional view of the component body 504 after the ceramic coating 508 has been deposited on the surface of the component body 504 (step 408). In this embodiment, the component body is aluminum with an anodized surface. In this example, the alumina ceramic coating is deposited using a thermal spraying process.

[0040] An ion exchange process forms a compression layer in the ceramic coating 508 (step 412). In this example, ion exchange is performed by applying a vacuum ion shock to the ceramic coating 508. The ion shock may be performed by biasing the ion plasma. The bias accelerates the ions and implants them into the ceramic coating 508. Figure 5B is a schematic cross-sectional view of the component body 504 after the compression layer 512 has been formed in the ceramic coating 508 (step 412). The ions take in more space, causing compression. The component is mounted as part of the plasma processing chamber 300 (step 416). The component is used in the plasma processing chamber 300 (step 420). It has been found that the ceramic coating 508 is hardened by the compression layer 512 and may be more resistant to cracks caused by stress during handling and temperature cycling. Therefore, the compression layer 512 helps prevent cracks caused by high temperatures.

[0041] In other embodiments, a tank may be used to perform ion exchange. A tank temperature above a certain temperature may be used to promote ion exchange. The ion exchange tank may be a molten salt tank at a temperature below the melting point of the ceramic coating 508. Alkali ions in the ceramic coating 508 may be exchanged for a larger volume of ions from a tank that induces compressive stress. In other embodiments, a diffusion step may be used to form the compression layer 512.

[0042] Figure 6 is a high-level flowchart of another embodiment. The component body is installed (step 604). In this embodiment, the component body is made of a conductive material such as aluminum. A diamond-like coating is formed on the surface of the component body (step 608). In one example of a process for depositing the diamond-like coating, a combination of heat and pressure is used, sp 2 The carbon atoms bonded by the bond are sufficiently compressed by sp 3 Carbon bonds are formed. In this embodiment, the diamond-like coating is an amorphous carbon material that exhibits some of the properties of diamond. The term diamond-like carbon is known in the art. Figure 7A is a schematic partial cross-sectional view of the component body 704 after the diamond-like carbon layer 708 has been deposited on the surface of the component body 704.

[0043] A ceramic coating is formed on the diamond-like carbon layer 708 (step 612). In this embodiment, the ceramic coating is formed by atomic layer deposition or chemical vapor deposition. Figure 7B is a schematic cross-sectional view of the component body 704 after the ceramic coating 712 has been formed on the diamond-like carbon layer 708. The component is mounted in the plasma processing chamber 300 (step 616). The component is used in the plasma processing chamber (step 624).

[0044] The diamond-like carbon layer 708 has high dielectric strength and high physical strength. However, the diamond-like carbon layer 708 is corroded by plasma containing oxygen or halogens. Therefore, a ceramic coating 712 is provided to protect the diamond-like carbon layer 708 from corrosion by plasma containing oxygen or halogens. The ceramic coating 712 may be thin. A more non-porous ceramic coating 712 is desirable. Ceramic coatings formed by atomic layer deposition or chemical vapor deposition have such properties. In this embodiment, the thickness of the second ceramic coating is 100 nanometers to 500 microns. The second ceramic coating has a porosity of less than 0.5%.

[0045] Figure 8 is a high-level flowchart of another embodiment. The component body is installed (step 804). In this example, the component body is aluminum. A metal oxide coating is deposited on the surface of the component body (step 808). In this example, the metal oxide coating is aluminum oxide (Al2O3). Instead of oxidizing the component body, the metal oxide is deposited by metal oxide chemical vapor deposition (MOCVD) or plasma-excited vapor deposition (PECVD) at low temperatures. In this embodiment, the metal oxide is formed at a temperature below 300°C. In other embodiments, the metal oxide is formed at a temperature below 200°C. In other embodiments, the metal oxide is formed at a temperature below 100°C. Figure 9 is a schematic cross-sectional view of the component body 904 having the metal oxide coating 908. The component is mounted in the plasma processing chamber 300 (step 812). The component is used in the plasma processing chamber 300 (step 816).

[0046] While this disclosure has been described in terms of several preferred embodiments, there are variations, substitutions, modifications, and various alternative equivalents that fall within the scope of this disclosure. It should also be noted that there are many alternative ways of carrying out the methods and apparatus of this disclosure. Therefore, the following appended claims are intended to be interpreted as including such variations, substitutions, and various alternative equivalents that fall within the true spirit and scope of this disclosure.

Claims

1. A component for use in a plasma processing chamber, A component body made of a conductive material, A first ceramic coating made of a first ceramic material on the surface of the component body, wherein the first ceramic material has a first side surface adjacent to the component body and a second side surface away from the component body, and the first ceramic material is a dielectric material, A second ceramic coating made of a second ceramic material on the second side surface of the first ceramic coating, wherein there is a gap between the first ceramic coating and the second ceramic coating, the gap is filled with at least one of a polymer material or a gas, and the second ceramic material is a dielectric material, and A component that includes the following features.

2. A component according to claim 1, A component wherein the first ceramic coating and the second ceramic coating include at least one of alumina, yttria, zirconia, stabilized zirconia, yttrium-aluminum mixture, erbium oxide, dysprosium oxide, cerium oxide, gadolinium oxide, magnesium aluminum spinel oxide, and ytterbium oxide.

3. A component according to claim 1, A component further comprising at least one support between the first ceramic coating and the second ceramic coating in order to maintain the gap between the first ceramic coating and the second ceramic coating.

4. A component according to claim 1, The component wherein the first ceramic material is the same as the second ceramic material.

5. A method for coating the main body of a component for use in a plasma processing chamber, The method involves forming a first ceramic coating on the surface of the component body, wherein the first ceramic coating has a first side surface adjacent to the component body and a second side surface separated from the component body, and the component body is made of a conductive material and the first ceramic coating is made of a dielectric material. A polymer layer having a first side adjacent to the second side of the first ceramic coating and a second side separated from the first ceramic coating is formed on the second side of the first ceramic coating, A second ceramic coating made of a dielectric material is formed on the second side surface of the polymer layer. Methods that include...

6. The method according to claim 5, A method further comprising removing the polymer layer after the formation of the second ceramic coating.

7. The method according to claim 5, A method wherein the first ceramic coating consists of a first ceramic material, the second ceramic coating consists of a second ceramic material, and the first ceramic material is the same as the second ceramic material.

8. A method for coating the main body of a component for use in a plasma processing chamber, A ceramic coating made of a dielectric material is formed on the surface of the component body made of a conductive material, The ion exchange process forms a compression layer in the ceramic coating. Methods that include...

9. The method according to claim 8, The method for forming the compression layer includes applying vacuum ion bombardment to the ceramic coating.

10. The method according to claim 8, The formation of the compression layer is a method comprising immersing the ceramic coating in a bath at a temperature sufficient to induce ion exchange, or a diffusion step of implanting ions into the ceramic coating.

11. A component manufactured by the method described in claim 8.

12. A component for use in a plasma processing chamber, A component body containing a conductive material, A diamond-like carbon coating is applied to the surface of the component body, A ceramic coating is applied on top of the diamond-like carbon coating. A component that includes the following features.

13. The component according to claim 12, A component wherein the ceramic coating is a dielectric coating formed by at least one of atomic layer deposition or chemical vapor deposition.

14. A method for coating the main body of a component for use in a plasma processing chamber, Forming a diamond-like carbon coating on the surface of the component body containing a conductive material, Depositing a ceramic coating on the aforementioned diamond-like carbon coating and Methods that include...

15. The method according to claim 14, A method for depositing the ceramic coating, comprising at least one of atomic layer deposition or chemical vapor deposition.

16. A method for coating the main body of a component for use in a plasma processing chamber, A method comprising depositing a metal oxide coating on the component body by performing at least one of metal oxide chemical vapor deposition or plasma-excited vapor deposition at a temperature of less than 300°C.

17. The method according to claim 16, A method wherein the component body contains aluminum and is electrically conductive.

18. A component manufactured by the method described in claim 16.

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