Patent Application
20190131113
Embodiments disclosed herein relate, in general, to protective coatings for semiconductor process chamber components, and in particular to corrosion and/or erosion resistant ceramic material coatings for semiconductor process chamber components.
In the semiconductor industry, devices are fabricated by a number of manufacturing processes producing structures of an ever-decreasing size. Some manufacturing processes such as plasma etch and plasma clean processes expose a substrate to a high-speed stream of plasma to etch or clean the substrate. The plasma may be highly corrosive, and may corrode processing chambers and other surfaces that are exposed to the plasma. This corrosion may generate particles, which frequently contaminate the substrate that is being processed, contributing to device defects. Additionally, the corrosion may cause metal atoms from chamber components to contaminate processed substrates (e.g., processed wafers).
As device geometries shrink, susceptibility to defects and particle contamination increases, and particle contaminant specifications become more stringent. To minimize defects and particle contamination introduced by chamber components during chamber processing, chamber components and chamber component coatings that are resistant to chamber processing conditions and are less likely to generate particles with the potential of contaminating a processed substrate are being developed.
In an example embodiment, a semiconductor process chamber component may comprise an article and a protective ceramic material coating. The protective ceramic material coating may comprise at least one phase material. The at least one phase material may comprise Y2O3 at a concentration of about 10 molar % to about 65 molar % and SiO2 at a concentration of about 35 molar % to about 90 molar %.
In an example embodiment, a method for coating an article may comprise creating a mixture of ceramic powders to form a protective ceramic material coating. The mixture of ceramic powders may comprise Y2O3 at a concentration of about 10 molar % to about 65 molar % and SiO2 at a concentration of about 35 molar % to about 90 molar %. The method may further comprise coating an article with a protective ceramic material coating.
In an example embodiment, a semiconductor process chamber component coating may comprise at least one phase material. The at least one phase material may comprise Y2O3 at a concentration of about 10 molar % to about 65 molar % and SiO2 at a concentration of about 35 molar % to about 90 molar %.
The present invention is illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings in which like references indicate similar elements. It should be noted that different references to “an” or “one” embodiment in this disclosure are not necessarily to the same embodiment, and such references mean at least one.
Embodiments disclosed herein are directed to protective ceramic material coatings, semiconductor process chamber components coated with a protective ceramic material coating, and processes of coating articles, e.g. semiconductor process chamber components, with a protective ceramic material coating. The protective ceramic material coating may have at least one phase material and an overall composition that includes Y2O3 at a concentration of about 10 molar % to about 65 molar %, about 20 molar % to about 60 molar %, about 25 molar % to about 55 molar %, or about 40 molar % to about 50 molar % and SiO2 at a concentration of about 35 molar % to about 90 molar %, about 40 molar % to about 80 molar %, about 45 molar % to about 75 molar %, or about 50 molar % to about 60 molar %. The protective ceramic material coating may be deposited by various techniques, including but not limited to, ion assisted deposition (IAD) (e.g., using electron beam IAD (EB-IAD) or ion beam sputtering IAD (IBS-IAD)), physical vapor deposition (PVD), chemical vapor deposition (CVD), atomic layer deposition (ALD), plasma spray, etc . . . . Use of chamber components coated with the protective ceramic material coating described herein may reduce yttrium metal contamination on processed wafers and also minimize particle generation, and enhance erosion and/or corrosion resistance of coated chamber components.
When the terms “about” and “approximate” are used herein, this is intended to mean that the nominal value presented is precise within ±10%.
When the phrase “at least one phase material” is used herein, it refers to a material that includes at least one state of matter but could also include a plurality of phases (i.e. state of matters) or a mixture of phases (i.e. state of matters) at the same time. For instance, a single phase may refer to a solid solution, whereas a plurality of phases may refer to a mixture of two or more solid phases.
In one embodiment, the processing chamber 100 includes a chamber body 102 and a showerhead 130 that enclose an interior volume 106. The showerhead 130 may or may not include a gas distribution plate. For example, the showerhead may be a multi-piece showerhead that includes a showerhead base and a showerhead gas distribution plate bonded to the showerhead base. Alternatively, the showerhead 130 may be replaced by a lid and a nozzle in some embodiments, or by multiple pie shaped showerhead compartments and plasma generation units in other embodiments. The chamber body 102 may be fabricated from aluminum, stainless steel or other suitable material. The chamber body 102 generally includes sidewalls 108 and a bottom 110.
An outer liner 116 may be disposed adjacent the sidewalls 108 to protect the chamber body 102. The outer liner 116 may be a halogen-containing gas resistant material such as Al2O3 or Y2O3. The outer liner 116 may also be coated with a protective ceramic material coating, in accordance with an embodiment.
An exhaust port 126 may be defined in the chamber body 102, and may couple the interior volume 106 to a pump system 128. The pump system 128 may include one or more pumps and throttle valves utilized to evacuate and regulate the pressure of the interior volume 106 of the processing chamber 100.
The showerhead 130 may be supported on the sidewalls 108 of the chamber body 102 and/or on a top portion of the chamber body. The showerhead 130 (or lid) may be opened to allow access to the interior volume 106 of the processing chamber 100, and may provide a seal for the processing chamber 100 while closed. A gas panel 158 may be coupled to the processing chamber 100 to provide process and/or cleaning gases to the interior volume 106 through the showerhead 130 or lid and nozzle. Showerhead 130 may be used for processing chambers used for dielectric etch (etching of dielectric materials). The showerhead 130 includes multiple gas delivery holes 132 throughout the showerhead 130. The showerhead 130 may be aluminum, anodized aluminum, an aluminum alloy (e.g., Al 6061), or an anodized aluminum alloy. In some embodiments, the showerhead includes a gas distribution plate (GDP) bonded to the showerhead. The GDP may be, for example, Si or SiC. The GDP may additionally include multiple holes that line up with the holes in the showerhead.
Examples of processing gases that may be used to process substrates in the processing chamber 100 include halogen-containing gases, such as C2F6, SF6, SiCl4, HBr, NF3, CF4, CHF3, CH2F3, F, Cl2, CCl4, BCl3 and SiF4, among others, and other gases such as O2, or N2O. Examples of carrier gases include N2, He, Ar, and other gases inert to process gases (e.g., non-reactive gases).
A substrate support assembly 148 is disposed in the interior volume 106 of the processing chamber 100 below the showerhead 130. The substrate support assembly 148 holds a substrate 144 (e.g., a wafer) during processing. The substrate support assembly 148 may include an electrostatic chuck that secures the substrate 144 during processing, a metal cooling plate bonded to the electrostatic chuck, and/or one or more additional components. An inner liner (not shown) may cover a periphery of the substrate support assembly 148. The inner liner may be a halogen-containing gas resistant material such as Al2O3 or Y2O3. The inner liner may also be coated with a protective ceramic material coating, in accordance with an embodiment.
Any of the showerhead 130 (or lid and/or nozzle), sidewalls 108, bottom 110, substrate support assembly 148, outer liner 116, inner liner (not shown), or other chamber component may include a protective coating, in accordance with embodiments. For example, as shown showerhead 130 includes a protective coating 152. In some embodiments, the protective coating 152 may be a protective ceramic material coating. In some embodiments, the protective ceramic material coating may comprise at least one phase material of Y2O3 and SiO2. The protective ceramic material coating is described in more detail with reference to
Exemplary articles may be selected from the group consisting of an electrostatic chuck, a nozzle, a gas distribution plate, a shower head, an electrostatic chuck component, a chamber wall, a liner, a liner kit, a gas line, a chamber lid, a nozzle, a single ring and a processing kit ring.
The protective ceramic material coating may comprise yttria (Y2O3), silica (SiO2), or a combination thereof, such as a solid solution of yttria and silica or a multiphase mixture. In certain embodiments, the protective ceramic material coating may be predominantly yttria and a portion of the protective ceramic material coating may be substituted with silica so as to minimize the potential of yttrium metal contaminants getting deposited on substrates during processing.
In one embodiment, the protective ceramic material coating may comprise at least one phase material of yttria and silica. In certain embodiments, the protective ceramic material coating may consist of or consist essentially of at least one phase material of yttria and silica. In certain embodiments, the concentration of Y2O3 and of SiO2 adds up to 100 molar %. In other embodiments, the at least one phase material may comprise additional constituents other than Y2O3 and SiO2. In one embodiment, the protective ceramic material coating may consist of only Y2O3 and SiO2 (in the form of one or more phases).
In one embodiment, the at least one phase material may comprise Y2O3 at a concentration of about 10 molar % to about 65 molar % and SiO2 at a concentration of about 35 molar % to about 90 molar % to. In one embodiment, the at least one phase material may comprise Y2O3 at a concentration of about 20 molar % to about 60 molar % and SiO2 at a concentration of about 40 molar % to about 80 molar %. In one embodiment, the at least one phase material may comprise Y2O3 at a concentration of about 25 molar % to about 55 molar % and SiO2 at a concentration of about 45 molar % to about 75 molar %. In one embodiment, the at least one phase material may comprise Y2O3 at a concentration of about 40 molar % to about 50 molar % and SiO2 at a concentration of about 50 molar % to about 60 molar %.
In one embodiment, the at least one phase material may comprise a composition selected from the group consisting of: a) Y2O3 at a concentration of about 65 molar % and SiO2 at a concentration of about 35 molar %, b) Y2O3 at a concentration of about 60 molar % and SiO2 at a concentration of about 40 molar %, c) Y2O3 at a concentration of about 55 molar % and SiO2 at a concentration of about 45 molar %, d) Y2O3 at a concentration of about 50 molar % and SiO2 at a concentration of about 50 molar %, e) Y2O3 at a concentration of about 45 molar % and SiO2 at a concentration of about 55 molar %, f) Y2O3 at a concentration of about 40 molar % and SiO2 at a concentration of about 60 molar %, g) Y2O3 at a concentration of about 35 molar % and SiO2 at a concentration of about 65 molar %, h) Y2O3 at a concentration of about 30 molar % and SiO2 at a concentration of about 70 molar %, i) Y2O3 at a concentration of about 25 molar % and SiO2 at a concentration of about 75 molar %, j) Y2O3 at a concentration of about 20 molar % and SiO2 at a concentration of about 80 molar %, k) Y2O3 at a concentration of about 15 molar % and SiO2 at a concentration of about 85 molar %, and l) Y2O3 at a concentration of about 10 molar % and SiO2 at a concentration of about 90 molar %.
Any of the aforementioned protective coatings may include trace amounts of other materials such as ZrO2, Al2O3, SiO2, B2O3, Er2O3, Nd2O3, Nb2O5, CeO2, Sm2O3, Yb2O3, or other oxides.
In one embodiment, EB-IAD is utilized to form the protective ceramic material coat 208. In one embodiment, IBS-IAD is utilized to form the protective ceramic material coat 208. In one embodiment, CVD is utilized to form the protective ceramic material coat 208. In one embodiment, PVD is utilized to form the protective ceramic material coat 208. In one embodiment, plasma spray is utilized to form the protective ceramic material coat 208. In one embodiment, ALD is utilized to form the protective ceramic material coat 208.
In one embodiment, the selected ceramic powders comprise Y2O3, SiO2, or a combination thereof. In one embodiment, the selected ceramic powders may consist of or consist essentially of yttria and silica. In certain embodiments, the concentration of Y2O3 and of SiO2 powders adds up to 100 molar %. In other embodiments, the selected ceramic powders may comprise additional constituents other than Y2O3 and SiO2.
In one embodiment, the ceramic powders include Y2O3 at a concentration of about 10 molar % to about 65 molar % and SiO2 at a concentration of about 35 molar % to about 90 molar % to. In one embodiment, the selected ceramic powders include Y2O3 at a concentration of about 20 molar % to about 60 molar % and SiO2 at a concentration of about 40 molar % to about 80 molar %. In one embodiment, the selected ceramic powders include Y2O3 at a concentration of about 25 molar % to about 55 molar % and SiO2 at a concentration of about 45 molar % to about 75 molar %. In one embodiment, the selected ceramic powders include Y2O3 at a concentration of about 40 molar % to about 50 molar % and SiO2 at a concentration of about 50 molar % to about 60 molar %.
In one embodiment, the selected ceramic powders include a composition selected from the group consisting of: a) Y2O3 at a concentration of about 65 molar % and SiO2 at a concentration of about 35 molar %, b) Y2O3 at a concentration of about 60 molar % and SiO2 at a concentration of about 40 molar %, c) Y2O3 at a concentration of about 55 molar % and SiO2 at a concentration of about 45 molar %, d) Y2O3 at a concentration of about 50 molar % and SiO2 at a concentration of about 50 molar %, e) Y2O3 at a concentration of about 45 molar % and SiO2 at a concentration of about 55 molar %, f) Y2O3 at a concentration of about 40 molar % and SiO2 at a concentration of about 60 molar %, g) Y2O3 at a concentration of about 35 molar % and SiO2 at a concentration of about 65 molar %, h) Y2O3 at a concentration of about 30 molar % and SiO2 at a concentration of about 70 molar %, i) Y2O3 at a concentration of about 25 molar % and SiO2 at a concentration of about 75 molar %, j) Y2O3 at a concentration of about 20 molar % and SiO2 at a concentration of about 80 molar %, k) Y2O3 at a concentration of about 15 molar % and SiO2 at a concentration of about 85 molar %, and l) Y2O3 at a concentration of about 10 molar % and SiO2 at a concentration of about 90 molar %.
At block 320, the selected ceramic powders are mixed. In some embodiment, the selected powders may be mixed with other components, including but not limited to, water, a binder, or a deflocculant to form a slurry.
At block 330, a deposition technique is selected for coating the article with the protective ceramic material coating. The deposition technique may be selected, without limitations, from the group consisting of IAD, CVD, PVD, ALD, and plasma spray.
At block 340, the ceramic powders mixture may be deposited on an article, such as a semiconductor process chamber component, using the deposition technique selected at block 330.
The article coated may be a semiconductor process chamber component selected, without limitations, from the group consisting of an electrostatic chuck, a lid, a nozzle, a gas distribution plate, a shower head, an electrostatic chuck component, a chamber wall, a liner, a liner kit, a chamber lid, a single ring, a processing kit ring, a gas line, and combinations thereof.
The protective ceramic material coating may be coated over different ceramic articles including oxide based ceramics, nitride based ceramics and carbide based ceramics. Examples of oxide based ceramics include SiO2 (quartz), Al2O3, Y2O3, and so on. Examples of carbide based ceramics include SiC, Si—SiC, and so on. Examples of nitride based ceramics include AN, SiN, and so on. The protective ceramic material coating may also be applied over a plasma sprayed protective layer. The plasma sprayed protective layer may be Y3Al5O12, Y2O3, Y4Al2O9, Er2O3, Gd2O3, Er3Al5O12, Gd3Al5O12, a ceramic compound comprising Y4Al2O9 and a solid-solution of Y2O3—ZrO2, or another ceramic.
In some embodiments, the method of coating an article with a protective ceramic material coating may further comprise forming one or more features in the protective ceramic material coating, in accordance with block 350. Forming one or more features may include grinding and/or polishing the protective ceramic material coating, drilling holes in the protective ceramic material coating, cutting and/or shaping the protective ceramic material coating, roughening the protective ceramic material coating (e.g., by bead blasting), forming mesas on the protective ceramic material coating, and so forth. In one embodiment, the one or more features may comprise at least one of holes, channels, or mesas.
As shown, the protective coat 415 is formed on an article 410 or on multiple articles 410A, 410B (shown in
With IAD processes, energetic particles 403 may be controlled by the energetic particle source 455 (e.g., energetic ion source) independently of other deposition parameters. The energy (e.g., velocity), density, working distance and incident angle of the energetic particle flux may be adjusted to control a composition, structure, crystalline orientation and grain size of the protective coat. Additional parameters that may also be adjusted are the article's temperature during deposition as well as the duration of the deposition. In certain embodiments, the deposition temperature (i.e., the temperature in the deposition chamber and the article therein) ranges from about 160° C. to about 500° C. or from about 200° C. to about 270° C. In certain embodiments, the working distance 470 between the material source 450 and the article 410A, 410B range from about 0.2 to about 2.0 meters or from about 0.2 to about 1.0 meters. In certain embodiments, the protective coating may have a non-uniformity of up to about 5-10%. In certain embodiments, the incident angle (i.e. the angle at which the deposition material from the material source strike the article) ranges from about 10-90 degrees or may be about 30 degrees.
IAD coatings can be applied over a wide range of surface conditions with roughness from about 0.5 micro-inches (On) to about 180 μin. However, smoother surface facilitates uniform coating coverage. The coating thickness can be up to about 1000 micrometers (μm). IAD coatings can be amorphous or crystalline depending on the material used to create the coating. Amorphous coatings are more conformal and reduce lattice mismatch induced epitaxial cracks whereas crystalline coatings are more erosion resistant.
Coating architecture can be a bi-layer or a multi-layer structure. In a bilayer architecture, an amorphous layer can be deposited as a buffer layer to minimize epitaxial cracks followed by a crystalline layer on the top which might be erosion resistant. In a multi-layer design, layer materials may be used to cause a smooth thermal gradient from the substrate to the top layer. Although possible variations in coating architecture are described herein with respect to IAD, it should be understood that such variations may also be accomplished if and/or when the protective coating is deposited by other techniques discussed herein (such as CVD, PVD other than IAD, ALD, and plasma spray) as well as by other techniques understood as equivalent to the techniques enumerated herein by one of ordinary skill in the art.
Co-deposition of multiple materials using multiple electron beam (e-beam) guns can be achieved to create thicker coatings as well as layered architectures. For example, two material sources having the same material type may be used at the same time. This may increase a deposition rate and a thickness of the protective coat. In another example, two material sources may be different ceramic materials or different metallic materials. A first electron beam gun may bombard a first material source to deposit a first protective coat, and a second electron beam gun may subsequently bombard the second material source to form a second protective coat having a different material composition than the first protective coat. Alternatively, the two electron beam guns may bombard the two material sources simultaneously to create a complex ceramic compound. Accordingly, two different metallic targets may be used rather than a single metal alloy to form a complex ceramic compound. Although co-deposition is described herein with respect to IAD, it should be understood that such co-deposition may also be accomplished if and/or when the protective coating is deposited by other techniques discussed herein (such as CVD, PVD other than IAD, ALD, and plasma spray) as well as by other techniques understood as equivalent to the techniques enumerated herein by one of ordinary skill in the art.
Post coating heat treatment can be used to achieve improved coating properties. For example, it can be used to convert an amorphous coating to a crystalline coating with higher erosion resistance. Although post coating heat treatment is described herein with respect to IAD, it should be understood that such post coating heat treatment may also be accomplished if and/or when the protective coating is deposited by other techniques discussed herein (such as CVD, PVD other than IAD, ALD, and plasma spray) as well as by other techniques understood as equivalent to the techniques enumerated herein by one of ordinary skill in the art.
The IAD apparatus depicted in
In some embodiments, the protective coating may be deposited on a surface of an article via CVD. An exemplary CVD system is illustrated in
CVD reactor 510 heats article 530 to a deposition temperature using heater 540. In some embodiments, the heater may heat the CVD reactor's wall (also known as “hot-wall reactor”) and the reactor's wall may transfer heat to the article. In other embodiments, the article alone may be heated while maintaining the CVD reactor's wall cold (also known as “cold-wall reactor”). It is to be understood that the CVD system configuration should not be construed as limiting. A variety of equipment could be utilized for a CVD system and the equipment is chosen to obtain optimum processing conditions that may give a coating with uniform thickness, surface morphology, structure, and composition.
The various CVD techniques include the following phases: (1) generate active gaseous reactant species (also known as “precursors”) from the starting material; (2) transport the precursors into the reaction chamber (also referred to as “reactor”); (3) absorb the precursors onto the heated article; (4) participate in a chemical reaction between the precursor and the article at the gas-solid interface to form a deposit and a gaseous by-product; and (5) remove the gaseous by-product and unreacted gaseous precursors from the reaction chamber.
Suitable CVD precursors may be stable at room temperature, may have low vaporization temperature, can generate vapor that is stable at low temperature, have suitable deposition rate (low deposition rate for thin film coatings and high deposition rate for thick film coatings), relatively low toxicity, be cost effective, and relatively pure. For some CVD reactions, such as thermal decomposition reaction (also known as “pyrolysis”) or a disproportionation reaction, a chemical precursor alone may suffice to complete the deposition. For other CVD reactions, other agents (listed in Table 1 below) in addition to a chemical precursor may be utilized to complete the deposition.
CVD has many advantages including its capability to deposit highly dense and pure coatings and its ability to produce uniform films with good reproducibility and adhesion at reasonably high deposition rates. Layers deposited using CVD in embodiments may have a porosity of below 1%, and a porosity of below 0.1% (e.g., around 0%). Therefore, it can be used to uniformly coat complex shaped components and deposit conformal films with good conformal coverage (e.g., with substantially uniform thickness). CVD may also be utilized to deposit a film made of a plurality of components, for example, by feeding a plurality of chemical precursors at a predetermined ratio into a mixing chamber and then supplying the mixture to the CVD reactor system.
The CVD reactor 510 may be used to form a protective coat that is resistant to erosion and/or corrosion in embodiments. Protective coat 525 and/or 545 may comprise a ceramic material such as Y2O3, SiO2, or any combination thereof including but not limited to a Y2O3 and SiO2 solid solution or multiphase mixture. The protective coat may comprise a bilayer or a multilayer architecture, various layers may have similar or different thicknesses, and the layers may independently be crystalline or amorphous. The materials forming the protective coat may be co-deposited. In some embodiments, the protective coat may be subject to post coating heat treatment. In some embodiments, the protective coat may be subject to post coating processing to form one or more features therein.
In some embodiments, the protective coating may be deposited on a surface of an article via a PVD technique (other than the IAD technique discussed earlier). PVD processes may be used to deposit thin films with thicknesses ranging from a few nanometers to several micrometers. The various PVD processes share three fundamental features in common: (1) evaporating the material from a solid source with the assistance of high temperature or gaseous plasma; (2) transporting the vaporized material in vacuum to the article's surface; and (3) condensing the vaporized material onto the article to generate a thin film layer. An illustrative PVD reactor is depicted in
The PVD reactor chamber 600 may be used to form a protective ceramic material coat in embodiments. Protective coat 625 and/or 645 may comprise a ceramic material such as Y2O3, SiO2, or any combination thereof including but not limited to a Y2O3 and SiO2 solid solution or multiphase mixture. The protective coat may comprise a bilayer or a multilayer architecture, various layers may have similar or different thicknesses, and the layers may independently be crystalline or amorphous. The materials forming the protective coat may be co-deposited. In some embodiments, the protective coat may be subject to post coating heat treatment. In some embodiments, the protective coat may be subject to post coating processing to form one or more features therein.
As the plasma gas is ionized and heated by the arc 706, the gas expands and is accelerated through a shaped nozzle 720, creating a high velocity plasma stream.
Powder 708 is injected into the plasma spray or torch (e.g., by a powder propellant gas) where the intense temperature melts the powder and propels the material as a stream of molten particles 714 towards the article 710. Upon impacting the article 710, the molten powder flattens, rapidly solidifies, and forms a coating 712, which adheres to the article 710. Coating 712 may be a protective ceramic material coating according to an embodiment. The parameters that affect the thickness, density, and roughness of the coating 712 include type of powder, powder size distribution, powder feed rate, plasma gas composition, plasma gas flow rate, energy input, torch offset distance, substrate cooling, etc.
Plasma spray apparatus 700 may be used to form a protective ceramic material coat in embodiments. Protective coat 712 may comprise a ceramic material such as Y2O3, SiO2, or any combination thereof including but not limited to a Y2O3 and SiO2 solid solution or multiphase mixture. The protective coat may comprise a bilayer or a multilayer architecture, various layers may have similar or different thicknesses, and the layers may independently be crystalline or amorphous. The materials forming the protective coat may be co-deposited. In some embodiments, the protective coat may be subject to post coating heat treatment. In some embodiments, the protective coat may be subject to post coating processing to form one or more features therein.
In
Film layer 815 may be a uniform, continuous and conformal. The film layer 815 may also have a very low porosity of less than 1% in embodiments, less than 0.1% in some embodiments, or approximately 0% in further embodiments. Subsequently, article 810 having surface 805 and film layer 815 may be introduced to a second precursor 870 that reacts with layer 815 to partially form a second film layer 820 by forming a second adsorption layer 818. Subsequently, article 810 may be introduced to another reactant 875 that reacts with adsorption layer 818 leading to a second half reaction to fully form the layer 820. The article 810 may alternately be exposed to the second precursor 870 and second reactant 875 up to m number of times to achieve a target thickness for the layer 820. m may be an integer from 1 to 100, for example. The second film layer 820 may be uniform, continuous and conformal. The second film layer 820 may also have a very low porosity of less than 1% in some embodiments, less than 0.1% in some embodiments, or approximately 0% in further embodiments.
In a similar manner, article 810 may continue to be introduced sequentially to the same or to other precursors and reactants until a final protective ceramic material coating according to an embodiment is formed.
In one embodiment, the final protective ceramic material coating may comprise a bilayer or a multilayer architecture of yttria and silica. In one embodiment, the final protective ceramic material coating may have alternating layers of yttria and silica. In one embodiment, the alternating layers of yttria and silica may have the same or different thickness. The layers may independently be crystalline or amorphous.
In certain embodiments, the ALD deposition may comprise exposing article, e.g., article 810, to multiple precursors, e.g. a yttrium-containing precursor and a silicon-containing precursor, and co-depositing the different precursors simultaneously. The ratio of the yttrium-containing precursor and the silicon-containing precursor may be selected to achieve a desired coating composition. Subsequently, article 810 may be exposed to a reactant such as an oxygen-containing reactant to form a final protective ceramic material coating comprising a plurality of oxides (e.g., yttria and silica).
In certain embodiments, the bilayer, multilayer, and/or co-deposited layer forming the final protective ceramic material coating may be annealed and/or interdiffused, for instance, through post-coating heat treatment. In embodiments the annealing process causes the Si and Y to interdiffuse between the alternating SiO2 and Y2O3 layers and form a uniform coating of a Y2O3—SiO2 solid solution or a multiphase mixture. In some embodiments, a post deposition annealing process is not performed and instead already deposited SiO2 and Y2O3 layers interdiffuse during deposition of subsequent layers. In some embodiments, the protective coat may be subject to post coating processing to form one or more features therein.
The surface reactions (e.g., half-reactions) described above, such as the reaction between the article's surface and the precursor(s) or the reaction between the precursor(s) and the reactant(s), are done sequentially. Prior to introduction of a new precursor(s) and/or a new reactant(s), the chamber in which the ALD process takes place may be purged with an inert carrier gas (such as nitrogen or air) to remove any unreacted precursors and/or reactants and/or surface-precursor reaction byproducts.
ALD processes may be conducted at various temperatures. The optimal temperature range for a particular ALD process is referred to as the “ALD temperature window.” Temperatures below the ALD temperature window may result in poor growth rates and non-ALD type deposition. Temperatures above the ALD temperature window may result in thermal decomposition of the article or rapid desorption of the precursor. The ALD temperature window may range from about 200° C. to about 400° C. In some embodiments, the ALD temperature window is between about 150° C. to about 350° C.
The ALD process allows for conformal film layers having uniform film thickness on articles and surfaces having complex geometric shapes, holes with large aspect ratios, and three-dimensional structures. Sufficient exposure time of the precursors to the surface enables the precursors to disperse and fully react with the surface in its entirety, including all of its three-dimensional complex features. The exposure time utilized to obtain conformal ALD in high aspect ratio structures is proportionate to the square of the aspect ratio and can be predicted using modeling techniques.
The final protective ceramic material coatings deposited by the ALD process discussed above may comprise a ceramic material such as Y2O3, SiO2, or any combination thereof including but not limited to a Y2O3 and SiO2 solid solution or a multiphase mixture.
Article 410 in
With the IAD, CVD, PVD, ALD, and plasma spray techniques, protective ceramic material coatings comprising Y2O3, SiO2, or any combination thereof including but not limited to a Y2O3 and SiO2 solid solution or a multiphase mixture, can be formed. The protective ceramic material coatings disclosed herein provide good erosion and/or corrosion resistance to the coated article. Additionally, there is a reduced likelihood of yttrium metal contamination on substrates that may get processed in chambers comprising chamber components coated with the protective ceramic material coatings disclosed herein. The beneficial properties of the protective ceramic material coatings disclosed herein may be independent from the deposition techniques in certain embodiments. In certain embodiments, the beneficial properties observed in a protective coating deposited by CVD, PVD other than IAD, ALD, and/or plasma spray may be comparable or superior to those observed in a protective coating that is deposited by IAD.
Exemplary yttrium-containing precursors that may be utilized with the CVD and ALD coating deposition techniques include, but are not limited to, tris(N,N-bis(trimethylsilyl)amide)yttrium (III), yttrium (III)butoxide, tris(cyclopentadienyl)yttrium(III), and Y(thd)3 (thd=2,2,6,6-tetramethyl-3,5-heptanedionato).
Exemplary silicon-containing precursors that may be utilized with the ALD and CVD coating deposition techniques include, but are not limited to, 2, 4, 6, 8-tetramethylcyclotetrasiloxane, dimethoxydimethylsilane, disilane, methylsilane, octamethylcyclotetrasiloxane, silane, tris(isopropoxy)silanol, tris(tert-butoxy)silanol, and tris (tert-pentoxy) silanol.
Exemplary oxygen-containing reactants that may be utilized with the various coating deposition techniques identified herein and their equivalent include, but are not limited to, ozone, water vapor, and oxygen radicals.
The preceding description sets forth numerous specific details such as examples of specific systems, components, methods, and so forth, in order to provide a good understanding of several embodiments of the present invention. It will be apparent to one skilled in the art, however, that at least some embodiments of the present invention may be practiced without these specific details. In other instances, well-known components or methods are not described in detail or are presented in simple block diagram format in order to avoid unnecessarily obscuring the present invention. Thus, the specific details set forth are merely exemplary. Particular embodiments may vary from these exemplary details and still be contemplated to be within the scope of the present invention.
Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, the appearances of the phrase “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment. In addition, the term “or” is intended to mean an inclusive “or” rather than an exclusive “or.”
Reference throughout this specification to numerical ranges should not be construed as limiting and should be understood as encompassing the outer limits of the range as well as each number and/or narrower range within the enumerated numerical range.
Although the operations of the methods herein are shown and described in a particular order, the order of the operations of each method may be altered so that certain operations may be performed in an inverse order or so that certain operation may be performed, at least in part, concurrently with other operations. In another embodiment, instructions or sub-operations of distinct operations may be in an intermittent and/or alternating manner.
It is to be understood that the above description is intended to be illustrative, and not restrictive. Many other embodiments will be apparent to those of skill in the art upon reading and understanding the above description. The scope of the invention should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.
This application claims priority to U.S. Provisional Patent Application No. 62/580,583, filed Nov. 2, 2017, which is herein incorporated by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 62580583 | Nov 2017 | US |
