Pyrochlore component for plasma processing chamber

Abstract

A component for use in a plasma processing chamber system is provided. The component body has a plasma facing surface. The plasma facing surface includes pyrochlore including at least one of zirconium and hafnium and at least one of lanthanum (La), samarium (Sm), yttrium (Y), erbium (Er), cerium (Ce), gadolinium (Gd), ytterbium (Yb), and neodymium (Nd).

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of priority to U.S. Application No. 63 / 408,571, filed on September 21, 2022, which is incorporated herein by reference for all purposes. Background Art

[0002] The background description provided here is for the purpose of generally presenting the context of the present disclosure. The information described in this background section and aspects of the specification that were not determined to be prior art at the time the application was filed are neither explicitly nor implicitly admitted to be prior art against the present disclosure.

[0003] The present disclosure generally relates to the manufacture of semiconductor devices. More specifically, the disclosure relates to plasma chamber components used in the manufacture of semiconductor devices.

[0004] During semiconductor wafer processing, plasma processing chambers are used to process semiconductor devices. Plasma processing chambers experience plasmas. These plasmas can degrade components. Coatings can be placed on plasma-facing surfaces of components of plasma processing chambers to protect those surfaces.

[0005] Some coatings can be applied using plasma spraying. One type of coating that can be used is aluminum oxide or alumina (Al 2 O 3 ). It has been found that aluminum oxide does not provide adequate etch resistance. Another type of coating that may be used is yttrium oxide or yttrium oxide (Y 2 O 3 ). It has been found that high purity yttria coatings are expensive to manufacture due to material costs and / or processing costs. Although yttria has better sputtering resistance than aluminum oxide, yttria is more susceptible to spontaneous fluorination or conversion than aluminum oxide. This fluorination reaction or conversion may be undesirable and result in harmful behavior. Summary of the invention

[0006] To achieve the above and in accordance with the purpose of this disclosure, a component for use in a plasma processing chamber system is provided. The component body has a surface facing the plasma. The surface facing the plasma includes pyrochlore, which includes at least one of zirconium and hafnium and at least one of lanthanum (La), samarium (Sm), yttrium (Y), erbium (Er), cerium (Ce), gadolinium (Gd), ytterbium (Yb) and neodymium (Nd).

[0007] In another specific example, a method of forming a component for use in a plasma processing chamber system is provided. The component body has a surface facing the plasma. The plasma-facing surface includes pyrochlore, the pyrochlore including at least one of zirconium (Zr) and hafnium (Hf) and at least one of lanthanum (La), samarium (Sm), yttrium (Y), erbium (Er), cerium (Ce), gadolinium (Gd), ytterbium (Yb), and neodymium (Nd).

[0008] These and other features of the present disclosure will be described in more detail in the following detailed description and in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The present disclosure is illustrated by way of example and not limitation in the accompanying figures and in which like reference numerals indicate similar elements and in which:

[0010] Figure 1 A high-level flowchart of the implementation scheme.

[0011] Figure 2A-2B is a schematic diagram of components processed according to an embodiment.

[0012] Figure 3 is a schematic diagram of a plasma processing chamber that may be used in embodiments.

[0013] In the accompanying drawings, similar reference numerals are sometimes used to designate similar structural elements. It should also be understood that the depictions in the drawings are schematic and not drawn to scale. DETAILED DESCRIPTION

[0014] The present invention will now 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 invention. However, it is apparent to those skilled in the art that the present invention can be implemented without some or all of these specific details. In other cases, known processing steps and / or structures are not described in detail to avoid making the present invention unnecessarily difficult to understand.

[0015] In the manufacture of semiconductor devices, a plasma processing chamber may be used. The plasma processing chamber may have various components that are exposed to the plasma during plasma processing. Such components may be aluminum to provide electrical and thermal properties useful for maintaining the plasma. Aluminum also allows for reductions in weight and cost. Other components may have a dielectric body. Such components may be made of alumina. Ceramic alumina can be used for items such as dielectric inductive power windows or gas injectors.

[0016] Such parts can be chemically etched by fluorine-containing plasmas, oxygen-containing plasmas, or chlorine-containing plasmas. In addition, the parts undergo chemical transformations or reactions that cause surface changes or bulk changes in the plasma-exposed areas of the parts. Erosion caused by sputtering can change the shape of the parts and destroy the uniformity of the plasma treatment, or can generate particles that become contaminants. A coating can be placed on the plasma-facing surface of the aluminum to provide protection against erosion.

[0017] Aluminum oxide is used as a protective coating. Aluminum oxide has some plasma etching resistance. More etch-resistant coatings will provide additional protection for such plasma chamber components. In some plasma processing chambers, coatings such as yttrium oxide and yttrium aluminum oxide are also used as coatings. Compared to aluminum oxide, yttrium oxide is more sputtering resistant. However, such yttrium oxide coatings do not meet the particle requirements of next-generation nodes. Instead, when exposed to a fluorine-containing plasma, the fluorine is absorbed into the yttrium oxide coating, causing the yttrium oxide coating to fluorinate, converting yttrium oxide (Y 2 O 3 ) is converted to yttrium fluoride (YF 3 ) or various forms of Y x O y F z Compounds, which may be stable or metastable. These compounds produce lattice and crystal defects with various inherent performance defects, resulting in particles that fall off from the yttrium oxide coating and become contaminants. These particles make it more difficult to meet the requirements of reducing contaminants. In addition, for example, due to the preferred fluorine conversion reaction of yttrium oxide, when exposed to a fluorine-containing plasma environment, some thermally sprayed yttrium oxide coatings may require an undesirably long period of time to reach a chemically stable state.

[0018] Various embodiments provide a component having a plasma-facing surface comprising pyrochlore. Pyrochlore is a material having the general formula A 2 B 2 O 7 A mineral wherein A and B are 3+ and 4+ metal cations, respectively. Pyrochlore materials are crystalline, but there is considerable variation in their crystal structure and stoichiometry. In some embodiments, there may be up to 10% excess A or B site cations. In some embodiments, the pyrochlore comprises at least one of zirconium (Zr) and hafnium (Hf) and at least one of lanthanum (La), samarium (Sm), yttrium (Y), erbium (Er), cerium (Ce), gadolinium (Gd), ytterbium (Yb) and neodymium (Nd). In some embodiments, the pyrochlore comprises at least one of zirconium and hafnium and at least one of La, Ce, and Gd. In some embodiments, the pyrochlore consists primarily of zirconium and La. In some embodiments, the pyrochlore is formed from a material that does not form volatile halides and is resistant to surface damage caused by ion bombardment.

[0019] For ease of understanding, Figure 1 A high level flow chart of the process used in the embodiments is provided. A component body is provided (step 104). Figure 2A 2 is a schematic cross-sectional view of a portion of a component body 204 of a component 200 in an embodiment. In this example, the component 200 is a ceramic alumina dielectric inductive power window. The component body 204 has a surface 208. In this embodiment, the surface 208 is a plasma-facing surface. The plasma-facing surface is the surface that will face the plasma when the component body 204 is used in a plasma processing chamber. In this embodiment, a layer 210 is formed on the plasma-facing surface. In some embodiments, one or more layers may be located on the plasma-facing surface. In other embodiments, no layer is located on the plasma-facing surface.

[0020] Next, the surface 208 and the layer 210 are coated with a pyrochlore coating 212. The pyrochlore coating 212 may be deposited on the surface by one or more of aerosol deposition (AD), atomic layer deposition (ALD), chemical vapor deposition (CVD), physical vapor deposition (PVD), and thermal spraying. In some embodiments, thermal spraying may be at least one of: suspended plasma spraying, vacuum plasma spraying, high velocity oxygen fuel spraying, and atmospheric plasma spraying. In some embodiments, the spray powder may be provided by forming a block of pyrochlore and grinding the block of pyrochlore into a powder. In some embodiments, the spray powder is formed from component powders of pyrochlore. For example, if the pyrochlore coating 212 is composed of a powder having the chemical formula La 2 Zr 2 O 7 The spray powder may include lanthanum oxide powder mixed with zirconium oxide (also known as zirconium dioxide) powder. In some embodiments, the pyrochlore coating 212 has a thickness of 100 nanometers to 300 micrometers. The surface of the pyrochlore coating 212 facing the plasma is the surface of the component 200 facing the plasma.

[0021] In some embodiments, the component body 204 comprises one or more of the following: a conductive metal or a ceramic. The conductive metal may comprise one or more of the following: aluminum or a refractory metal. In some embodiments, the refractory metal may comprise one or more of the following: stainless steel, titanium, or a nickel alloy. In some embodiments, the nickel alloy contains at least 50% Ni (by weight). In some embodiments, if the coating deposition process causes the component body 204 to be heated to a temperature of at least 200° C. for at least 10 hours, the component body 204 is referred to as a refractory metal. In some embodiments, the component body 204 comprises aluminum. The aluminum component body may be an aluminum alloy, such as aluminum 6061. Such an aluminum alloy is at least 95% pure aluminum (by weight). In some embodiments, the layer 210 may be one or more layers of anodized or other layers. In other embodiments, there is no layer, and the pyrochlore coating 212 is directly located on the surface 208. In some embodiments, the component body 204 comprises a ceramic dielectric material, such as aluminum oxide. In some embodiments, the coating can be produced using ceramic powders by a variety of methods known in the art. These methods include: thermal spraying (plasma, HYO F, detonation gun, etc.), electron beam physical vapor deposition (EBPVD), laser cladding, and plasma transferred arc. If the coating technology used is electron beam physical vapor deposition (EB-CVD), the ceramic target used can be a pyrochlore - for example: lanthanum oxide (powder or block).

[0022] In some embodiments, the pyrochlore coating is patterned. In some embodiments, the pattern is provided by masking the surface of the component body 204 prior to applying the coating.

[0023] In some embodiments, the bulk component body 204 comprises pyrochlore. In such embodiments, the layer 210 and the pyrochlore coating 212 are not required because the surface facing the plasma is the surface of the pyrochlore facing the plasma. In some embodiments, the bulk component body 204 is formed by a sintering process. In some embodiments, the component body 204 is formed by a spark plasma sintering process. In some embodiments, the ceramic powder can be provided by forming a bulk pyrochlore and forming the bulk pyrochlore into a powder. In some embodiments, the ceramic powder is formed from component powders of pyrochlore. For example: if the component body is formed of LZO, the ceramic powder may include a lanthanum oxide powder mixed with a zirconium oxide powder.

[0024] In some embodiments, the block component body 204 includes a plurality of ceramic layers laminated together to form a ceramic laminate, wherein at least one surface of the block component body is pyrochlore. In some embodiments, the ceramic laminate forming the component body 204 can be formed by a sintering process, such as a spark plasma sintering process. In one example, a first ceramic powder can be placed in a mold. The first ceramic powder can fill more than 90% of the mold. A layer of a second ceramic powder is placed on top of the first ceramic powder in the mold. The second ceramic powder can fill less than 10% of the mold. The second ceramic powder is a powder formed by pyrochlore. In some embodiments, the second ceramic powder can be provided by forming a block pyrochlore and forming the block pyrochlore into a powder. In some embodiments, the second ceramic powder is formed by a component powder of pyrochlore. For example: if the second ceramic powder is used to form LZO, the ceramic powder may include a lanthanum oxide powder mixed with a zirconium oxide powder. In some embodiments, the first ceramic powder does not form pyrochlore. For example, the first ceramic powder may be an aluminum oxide to form an aluminum oxide ceramic portion. In some embodiments, the formed component comprises a ceramic component body of the first ceramic powder and a protective pyrochlore layer located on the surface of the ceramic component body. In some embodiments, a transition region of the mixture of the first ceramic powder and the second ceramic powder is between the component body of the first ceramic powder and the pyrochlore layer. In some embodiments, when additional layers of different ceramic powders are provided, the ceramic component body may further comprise additional ceramic layers and transition layers.

[0025] The component body 204 is installed in a plasma processing chamber (step 108). In this example, the component body 204 is installed in the plasma processing chamber to serve as a dielectric inductive power window. The plasma processing chamber is used to process a substrate (step 112), wherein a plasma is generated in the chamber to process the substrate, such as to etch the substrate, and the pyrochlore surface is exposed to the plasma. The pyrochlore provides increased etch resistance to protect the surface 208 of the component body 204.

[0026] Figure 3An example of a plasma processing chamber system 300 that can be used in an embodiment is schematically depicted. The plasma processing chamber system 300 includes a plasma reactor 302 having a plasma processing confinement chamber 304 therein. A plasma power supply 306 tuned by a plasma matching network 308 supplies power to a variable voltage coupled plasma (TCP) coil 310 located near a dielectric inductive power window 312 to generate a plasma 314 in the plasma processing confinement chamber 304 by providing inductively coupled power. A pinnacle 372 extends from a chamber wall 376 of the plasma processing confinement chamber 304 to the dielectric inductive power window 312, thereby forming a pinnacle ring. The pinnacle 372 is angled with respect to the chamber wall 376 and the dielectric inductive power window 312, such that the inner angle between the pinnacle 372 and the chamber wall 376 and the inner angle between the pinnacle 372 and the dielectric inductive power window 312 are each greater than 90° and less than 180°. As shown, the spire 372 provides an angled ring near the top of the plasma processing confinement chamber 304. The spire 372 is more commonly referred to as a chamber liner. The TCP coil (upper power supply) 310 can be configured to produce a uniform diffusion profile in the plasma processing confinement chamber 304. For example, the TCP coil 310 can be configured to produce a ring-shaped power distribution in the plasma 314. The dielectric inductive power window 312 is provided to separate the TCP coil 310 from the plasma processing confinement chamber 304 while allowing energy to be transferred from the TCP coil 310 to the plasma processing confinement chamber 304. The wafer bias power supply 316, tuned by the bias matching network 318, provides power to the electrode 320 to set the bias on the substrate 366. The substrate 366 is supported by the electrode 320. The controller 324 controls the plasma power supply 306 and the wafer bias power supply 316.

[0027] The plasma power supply 306 and the wafer bias power supply 316 can be configured to operate at a specific RF frequency (e.g., 13.56 megahertz (MHz), 27 MHz, 2 MHz, 60 MHz, 400 kilohertz (kHz), 2.54 gigahertz (GHz), or a combination thereof). The plasma power supply 306 and the wafer bias power supply 316 can be appropriately resized to supply a range of powers to achieve the desired processing performance. For example, in one embodiment, the plasma power supply 306 can supply power in the range of 50 to 5000 watts, and the wafer bias power supply 316 can supply a bias in the range of 20 to 2000 volts (V). In addition, the TCP coil 310 and / or the electrode 320 can be composed of two or more sub-coils or sub-electrodes. These sub-coils and sub-electrodes can be powered by a single power supply or by multiple power supplies.

[0028] like Figure 3As shown, the plasma processing chamber system 300 also includes a gas source / gas supply mechanism 330. The gas source 330 is fluidly connected to the plasma processing confinement chamber 304 via a gas inlet such as a gas injector 340. The gas injector 340 can be located in any advantageous position in the plasma processing confinement chamber 304 and can inject gas in any form. However, the gas inlet is preferably configured to produce an "adjustable" gas injection profile. The adjustable gas injection profile allows independent adjustment of the corresponding gas flow rates flowing to multiple regions in the plasma processing confinement chamber 304. More preferably, the gas injector is mounted to the dielectric induction power window 312. The gas injector can be mounted on the power window, in the power window, or form a part of the power window. Processing gas and byproducts are removed from the plasma processing confinement chamber 304 via a pressure control valve 342 and a pump 344. The pressure control valve 342 and the pump 344 are also used to maintain a specific pressure in the plasma processing confinement chamber 304. The pressure control valve 342 can maintain a pressure of less than 1 Torr during processing. An edge ring 360 is disposed around the substrate 366. The gas source / gas supply mechanism 330 is controlled by the controller 324. The Kiyo series of products from Lam Research Corp. (Fremont, CA) may be used to implement embodiments.

[0029] In various embodiments, the component may be other parts of a plasma processing chamber, such as a confinement ring, an edge ring, an electrostatic chuck, a gas injector, a grounding ring, a chamber liner (e.g., turret 372), a door liner, a dielectric window, a chamber wall, or other components. Other types of other components of a plasma processing chamber may be used. For example: In an embodiment, a plasma confinement ring on a bevel etch chamber may be coated with a coating. In another example, a showerhead of a dielectric processing chamber may be coated with a coating. In some embodiments, the chamber may have a dome shape, wherein the coating coats the dome. In some embodiments, one or more (but not all) surfaces of the component body 204 are coated with a coating.

[0030] In some embodiments, after the coating is deposited, the coating is subjected to machining, grinding and / or polishing. In one example, the part may have a surface with a complex shape. Because the surface has a complex shape, the thickness of the coating may be uneven. Machining, grinding, and / or polishing can be used to provide a more uniform thickness. The uniform thickness can improve the uniformity of the treatment, control the stress of the coating to avoid mechanical coating failure, and ensure that the part can cooperate with adjacent parts. In one embodiment, a coating with a thickness of about 1500 microns is deposited. Machining and grinding reduce the thickness of the coating to a uniform thickness of less than 1000 microns. Polishing using very fine high hardness abrasives (abrasive) embedded in a polishing pad or slurry can be used to reduce the roughness of the coating so that the surface of the chamber facing the plasma has a uniform roughness. In some embodiments, the roughness is less than 5 microns Ra. Such roughness can be achieved by spraying or basic machining and / or grinding. In some embodiments, the roughness is less than 1.5 microns Ra. In some embodiments, the roughness is between 0.5 microns Ra and 1.5 microns Ra. In some embodiments, the roughness is between 0.005 microns Ra and 0.5 microns Ra.

[0031] Although the present disclosure has been described according to several preferred embodiments, there are changes, permutations, modifications and various alternative equivalents that fall within the scope of the present invention. It should also be noted that there are many alternatives to implement the method and apparatus of the present invention. Therefore, the following claims are intended to be interpreted as including all such changes, permutations and various alternative equivalents that fall within the true spirit and scope of the present invention. As used herein, the phrase "A, B or C" should be interpreted as representing the logic ("A or B or C") using a non-exclusive logic "OR", and should not be interpreted as representing "only" one of A or B or C. The various steps in the process may be selective and non-essential steps. Different embodiments may have one or more steps removed or the steps may be in different orders. In addition, various embodiments may provide different steps simultaneously rather than sequentially.

Claims

1. A component for use in a plasma processing chamber system, comprising a component body having a plasma-facing surface, wherein the plasma-facing surface comprises pyrochlore, the pyrochlore comprising: at least one of zirconium and hafnium; and At least one of lanthanum (La), samarium (Sm), yttrium (Y), erbium (Er), cerium (Ce), gadolinium (Gd), ytterbium (Yb), and neodymium (Nd).

2. The component of claim 1, wherein the pyrochlore comprises zirconium and La.

3. The component of claim 1, wherein the component body comprises the pyrochlore forming a block-shaped component body.

4. The component of claim 1, wherein the plasma-facing surface comprises a coating located on a surface of the component body. The component of claim 4 , wherein the component body comprises an electrically conductive metal.

6. The component of claim 5, wherein the conductive metal is a refractory metal.

7. The component of claim 4, wherein the component body comprises ceramic.

8. The component of claim 4, wherein the coating has a thickness in the range of 100 nanometers to 300 micrometers.

9. The component of claim 1, wherein the component forms at least one of a gas injector, a chamber liner, a chamber wall, and a dielectric window. 10 . The component according to claim 1 , wherein the component body comprises a ceramic laminate layer comprising a ceramic component body of a first ceramic powder and a pyrochlore layer on a surface of the component body.

11. The component of claim 10, wherein the ceramic component body of the first ceramic powder is not pyrochlore.

12. A method of forming a component for use in a plasma processing chamber system, the method comprising providing a component body having a plasma-facing surface, wherein the plasma-facing surface comprises pyrochlore, the pyrochlore comprising at least one of zirconium (Zr) and hafnium (Hf), and at least one of lanthanum (La), samarium (Sm), yttrium (Y), erbium (Er), cerium (Ce), gadolinium (Gd), ytterbium (Yb), and neodymium (Nd).

13. The method of claim 12, forming the component body comprising spark plasma sintering ceramic powder.

14. The method of claim 12, wherein forming the component body comprises: providing a block component body; and A pyrochlore coating is formed on the surface of the block body.

15. The method of claim 14, wherein forming the pyrochlore coating is performed by at least one of: atomic layer deposition, aerosol deposition, thermal spraying, PVD, and CVD.

16. The method of claim 12, wherein the pyrochlore comprises zirconium and La.

17. A product made by the method according to claim 12.

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