Diffusion bonding of pure metals

Abstract

The method includes applying a bonding layer of a first chemical composition to a first surface of a first metal body, the metal body being of a second chemical composition. The method further includes placing a second metal body of a second chemical composition against the first metal body such that the bonding layer is between the first surface of the first metal body and the second surface of the second metal body. The metal bodies are resistant to diffusion bonding. The bonding layer promotes diffusion bonding of the metal bodies. The method further includes heating the first metal body and the second metal body. The method further includes applying pressure to press the second metal body against the first metal body. The method further includes creating a diffusion bond between the metal bodies in response to heating and applying pressure for a period of time.

Description

Technical Field

[0001]

[0001] Embodiments of the present disclosure relate to forming an article using diffusion bonding. More specifically, embodiments of the present disclosure relate to forming an article from a pure metal body using diffusion bonding.

Background Art

[0002]

[0002] In a manufacturing and processing system (e.g., a processing chamber), the conditions proximate to a workpiece (e.g., a substrate, a semiconductor wafer, etc.) determine the result of the processing. The conditions are controlled by the components of the processing system. Depending on the application, it may be necessary to process a substrate in a harsh environment such as high temperature, a corrosive environment (e.g., a plasma environment, a fluorine gas environment), high voltage, etc. The process may be sensitive to the materials selected to make up the components of the processing apparatus. For example, aluminum may not be suitable for a high temperature environment. In some cases, a small amount of contaminants (e.g., alloying agents) contained in the material of the component may leach into the substrate, causing unexpected or unacceptable performance.

[0003]

[0003] In some cases, the components will have complex shape dimensions. Components with complex shape dimensions, especially complex internal shape dimensions, may be inconvenient, difficult, or impossible to machine. Diffusion bonding is one way to form components with complex internal shape dimensions. Diffusion bonding utilizes a concentration gradient (e.g., between two different metals) to facilitate the exchange of atoms between two metal bodies and join them into one solid object or article. Diffusion bonding is generally not suitable for joining two pure metal bodies composed of the same metal.

Summary of the Invention

[0004]

[0004] The following is a brief overview of the Disclosure to provide a basic understanding of some aspects of the Disclosure. This overview is not an exhaustive overview of the Disclosure. It is not intended to identify any key points or important elements of the Disclosure, nor to define any scope of any particular embodiment of the Disclosure or any scope of any claim. The sole purpose of this overview is to present some of the concepts of the Disclosure in a simplified form as a prelude to the more detailed explanations that follow.

[0005]

[0005] In one embodiment of the present disclosure, the disclosed method includes applying a bonding layer of a first chemical composition to a first surface of a first metal body. The metal body has a second chemical composition, which is different from the first chemical composition. The method further includes positioning a second metal body of a second chemical composition relative to the first metal body such that the bonding layer is between the first surface of the first metal body and the second surface of the second metal body. The first and second metal bodies are resistant to diffusion bonding. The bonding layer facilitates the diffusion bonding of the second metal body to the first metal body. The method further includes heating the first and second metal bodies. The method further includes applying pressure to press the second metal body against the first metal body. The method further includes generating a diffusion bond between the second metal body and the first metal body in response to heating and applying pressure for a certain period of time.

[0006]

[0006] In other aspects of the present disclosure, a chamber component for a processing chamber is disclosed. The chamber component comprises a first substantially pure metal body. The first metal body is composed of a first chemical composition. The chamber component further comprises a second substantially pure metal body. The second metal body is composed of a first chemical composition. The first chemical composition is resistant to diffusion bonding. The chamber component further comprises a diffusion bond between a first surface of the first metal body and a second surface of the second metal body, the diffusion bond comprising a spatial gradient between the first and second chemical compositions of the bonding layer, from the first metal body through the bonding layer to the second metal body.

[0007]

[0007] In other aspects of the present disclosure, a processing chamber is disclosed. The processing chamber includes a shower head. The shower head includes a first substantially pure metal body having a first chemical composition. The shower head includes a second substantially pure metal body having a first chemical composition. The first chemical composition is resistant to diffusion bonding. The shower head further includes a diffusion bond between a first surface of the first metal body and a second surface of the second metal body. The diffusion bond consists of a spatial gradient of the first and second chemical compositions of the bonding layer, the spatial gradient from the first metal body through the bonding layer to the second metal body.

[0008]

[0008] Embodiments of the present invention are shown in the accompanying drawings as examples, not as limitations, where similar reference numerals indicate similar elements. It should be noted that references to “an” or “one” embodiments in this disclosure do not necessarily refer to the same embodiment, but rather mean at least one. [Brief explanation of the drawing]

[0009] [Figure 1]

[0009] This is a cross-sectional view of a processing chamber having one or more chamber components that can be manufactured from substantially pure metal by diffusion bonding according to some embodiments. [Figure 2]

[0010] A diffusion bonding system is shown, including cross-sectional views of diffusion bonding chambers according to several embodiments. [Figure 3]

[0011] This document illustrates an exemplary architecture of a deposition system for carrying out aerosol deposition according to several embodiments. [Figure 4A-4B]

[0012] Several embodiments of a mechanism and apparatus for implementing a deposition technique using energy particles are shown. [Figure 5]

[0013] A schematic diagram of a plasma spray deposition apparatus used in several embodiments of thermal spray deposition techniques is shown. [Figure 6]

[0014] Schematic diagrams of electroplating systems for applying bonding layer coatings, according to several embodiments, are shown. [Figure 7]

[0015] This is a flowchart of a method for manufacturing a diffusion-bonded article composed of substantially pure metal according to several embodiments. [Figure 8A-8B]

[0016] A cross-sectional view of an exemplary article formed from a substantially pure metal body using diffusion bonding according to several embodiments is shown. [Modes for carrying out the invention]

[0010]

[0017] This specification describes an improved method for manufacturing components for processing chambers. In particular, an improved method for manufacturing pure metal components of processing chambers (such as those that can be used as components of semiconductor processing equipment) is disclosed by diffusion bonding. Components of the processing equipment may include internal structures such as channels and openings. The properties of the components (e.g., dimensions including internal dimensions) affect the conditions in which the product manufactured by the processing equipment is located. The conditions in which the workpiece is located determine the properties of the final product. For example, a processing chamber can be used to process substrates such as semiconductor wafers. The properties of the components of the processing chamber affect the processing conditions that the substrate is subjected to. The conditions in which the substrate is located determine the performance of the product (e.g., whether the final product exhibits the target characteristic values).

[0011]

[0018] In some embodiments, the target processing component (e.g., target shape dimensions) may be inconvenient or impossible to machine from solid raw materials, such as components with complex internal structures. Some conventional systems may compromise to achieve the feasibility of the configuration, such as designing components with machinable structures or using multiple pieces joined together by clamping, bonding, or other means.

[0012]

[0019] Some manufacturing processes are sensitive to contaminants. In such processes, the materials that make up the components can be selected to avoid materials that could contaminate the target product. For example, some materials can leak from the components being processed and adversely affect the performance of semiconductor wafers. Many bonding agents contain materials that can contaminate the manufacturing process, so multi-piece components bonded by these bonding agents can be affected by this sensitivity to contaminants.

[0013]

[0020] Diffusion bonding is a bonding technique that operates on the principle of solid diffusion. Under certain conditions, atoms on the surfaces of two solid metals mix together over time. Diffusion bonding can be performed by applying high pressure to two metal bodies in a high-temperature environment. Atoms from the two metal bodies are gradually exchanged until the interface between the two articles disappears and a single article is formed.

[0014]

[0021] Diffusion bonding occurs due to the overall (e.g., two dissimilar metals) or local (e.g., two different local environments) concentration of materials. Dissimilar metals are often good candidates for diffusion bonding. Alloys can also be bonded by diffusion bonding due to the fact that they contain multiple constituent materials. However, in some applications, the target components are to be made of pure metals free of contaminants. In such applications, the metal body is resistant to diffusion bonding, and diffusion bonding is not feasible.

[0015]

[0022] Aspects of this disclosure address at least some of the shortcomings of conventional methods. Disclosed herein are chamber components and techniques for producing chamber components of pure metals by diffusion bonding. Embodiments enable the production of metal bodies of a single pure metal composition and / or complex internal structures. These metal bodies are free of contaminants. In some embodiments, a thin layer of a second material is placed between the pure metal bodies, the second material being different from the material of the pure metal bodies. A diffusion bonding procedure is then performed. The concentration gradient between the pure material and the second material facilitates the exchange of atoms between the materials. Unlike articles brazed or otherwise bonded, diffusion-bonded articles do not have a distinct bonding layer. Instead, diffusion-bonded articles exhibit a concentration gradient from the pure metal to the region where the second material has diffused into the pure metal, creating a mixed material (e.g., an alloy) in the region between the two metal bodies, which can then return to the pure metal.

[0016]

[0023] In some aspects of the present disclosure, a method comprises forming a first substantially pure metal body. The first substantially pure metal body comprises a first chemical composition. The method further comprises forming a second substantially pure metal body comprising the first chemical composition. The method further comprises applying a bonding layer comprising a second chemical composition different from the first chemical composition to a first surface of the first metal body. The method further comprises arranging the metal bodies such that the bonding layer is between a first surface of the first metal body and a second surface of the second metal body. The method further comprises creating a diffusion bond between the first metal body and the second metal body by applying a certain pressure and temperature for a certain period of time to join the first metal body and the second metal body.

[0017]

[0024] In other aspects of this disclosure, chamber components for a processing chamber are disclosed. The chamber component comprises a first substantially pure metal body having a first chemical composition. The chamber component further comprises a second substantially pure metal body having the first chemical composition. The chamber component further comprises a diffusion bond between a first surface of the first metal body and a second surface of the second metal body. The diffusion bond comprises a spatial gradient of the first and second chemical compositions of the bonding layer, the spatial gradient from the first metal body through the bonding layer to the second metal body. The second chemical composition may be different from the first chemical composition. For example, the first chemical composition may be a pure metal and the second chemical composition may be an alloy of pure metals. The chemical composition of the chamber component comprises a spatial gradient from the first metal body through the bonding layer to the second metal body.

[0018]

[0025] In other aspects of this disclosure, a processing chamber is disclosed. The processing chamber includes a showerhead. The showerhead includes a first substantially pure metal body having a first chemical composition. The showerhead includes a second substantially pure metal body having a first chemical composition. The first chemical composition is resistant to diffusion bonding. The showerhead further includes a diffusion bond between a first surface of the first metal body and a second surface of the second metal body. The diffusion bond consists of a spatial gradient between the first and second chemical compositions, from the first metal body through the bonding layer to the second metal body.

[0019]

[0026] FIG. 1 is a cross-sectional view of a processing chamber 100 having one or more chamber components that can be manufactured from substantially pure metal by diffusion bonding according to some embodiments. The processing chamber 100 may include components having complex internal structures, such as showerheads (e.g., internal structures that cannot be machined from solid blocks). The processing chamber 100 can be used in processes that provide a plasma corrosion environment having plasma processing conditions. For example, the processing chamber 100 may be a chamber for a plasma etching apparatus or plasma etching reactor, a plasma cleaner, etc. The processing chamber 100 may be used in contamination-sensitive processes, such as semiconductor wafer processing. Examples of chamber components that can be part of the processing chamber 100 include a substrate support assembly 104, an electrostatic chuck (ESC), rings (e.g., a process kit ring or a single ring), chamber walls, a base, a gas distribution plate, a showerhead 106, nozzles, a lid, a liner, a liner kit, a shield, a plasma screen, a flow equalizer, a cooling base, a chamber viewport, a chamber lid, etc.

[0020]

[0027] In one embodiment, the processing chamber 100 includes a chamber body 108 surrounding an internal space 110 and a showerhead 106. The showerhead may include a showerhead base and a showerhead gas distribution plate. Alternatively, in some embodiments, the showerhead 106 can be replaced with a lid and nozzles. The chamber body 108 can be manufactured from aluminum, stainless steel, nickel, or other suitable materials. The chamber body 108 generally includes sidewalls 112 and a bottom 114. Any of the showerhead 106 (or lid and / or nozzles), sidewalls 112, and / or bottom 114 may include an arc and / or a plasma-resistant coating layer.

[0021]

[0028] The exhaust port 116 is defined in the chamber body 108 and connects the internal space 110 to the pump system 118. The pump system 118 may include one or more pumps and throttle valves utilized to evacuate the internal space 110 of the processing chamber 100 and regulate the pressure in the internal space 106.

[0022]

[0029] The showerhead 106 may be supported on the sidewall 112 of the chamber body 108. The showerhead 106 (or lid) may be open to allow access to the internal space 110 of the processing chamber 100 and may provide a seal for the processing chamber 100 in a closed state. A gas panel 120 may be connected to the processing chamber 100 to supply process gas and / or cleaning gas to the internal space 110 via the showerhead 106 or lid and nozzles. The showerhead 106 is used in a processing chamber for dielectric etching (etching of dielectric materials). The showerhead 106 includes a gas distribution plate (GDP) having a plurality of gas supply holes throughout the GDP. The showerhead 106 is an example of a component that can be manufactured using the diffusion bonding technology described in the present disclosure. The showerhead 106 may include a complex internal structure. The showerhead 106 may be composed of substantially pure metal. In some embodiments, "substantially pure" refers to a metal having a purity of at least 99.9%. In some embodiments, the materials used to manufacture components using diffusion bonding (such as the showerhead 106) may have a purity of at least 99.99%. In some embodiments, the materials used to manufacture components using diffusion bonding may have a purity of at least 99.999%. In some embodiments, the showerhead 106 may be composed of substantially pure metal.

[0023]

[0030] For processing chambers used in conductive etching (etching conductive materials), a lid may be used instead of a showerhead. The lid may include a central nozzle that fits into a central hole in the lid. The lid may be made of ceramic, such as Al2O3, Y2O3, YAG, or a ceramic compound containing a solid solution of Y4Al2O9 and Y2O3-ZrO2. The nozzle may also be made of ceramic, such as Y2O3, YAG, or a ceramic compound containing a solid solution of Y4Al2O9 and Y2O3-ZrO2. The lid, showerhead base, GDP, and / or nozzle may be coated with an arc layer and / or a plasma-resistant coating layer.

[0024]

[0031] Examples of process gases that may be used to process the substrate in the processing chamber 100 include halogen-containing gases (especially C2F6, SF6, SiCl4, HBr, NF3, CF4, CHF3, CH2F3, F, NF3, Cl2, CCl4, BCl3, SiF4, etc.) and other gases such as O2 or N2O. Examples of carrier gases include N2, He, Ar, and other gases that are inert to the process gas (e.g., non-reactive gases). A substrate support assembly 104 is located under the showerhead 106 or lid in the internal space 1110 of the processing chamber 100. The substrate support assembly 104 holds the substrate 102 during processing. A ring (e.g., a single ring) can cover a portion of the support assembly 104 (e.g., a susceptor 122) to protect the covered portion from exposure to the plasma during processing. In some embodiments, the ring is silicon or quartz. The substrate support assembly 104 may include a pedestal 124 and a susceptor 122.

[0025]

[0032] Figure 2 shows a diffusion bonding system, including a cross-sectional view of a diffusion bonding chamber 202 according to several embodiments. The diffusion bonding system 200 can be configured to perform diffusion bonding of two metal bodies composed of substantially pure metals, such as substantially pure (e.g., 99.9% purity or higher) nickel.

[0026]

[0033] The diffusion bonding system 200 includes a diffusion bonding chamber 202 having an interior 204 enclosed by walls and a bottom. In some embodiments, the interior 204 may be a sealed chamber capable of maintaining low or high pressure conditions or capable of processing articles in an inert gas environment and may be connected to a suitable gas flow source. In some embodiments, the diffusion bonding chamber 202 includes a furnace 206 which may enclose the diffusion bonding chamber 202, for example, in a cylindrical shape. The furnace 206 may be programmable and include one or more temperature sensors positioned within the hot-press chamber 202 to provide feedback used to maintain a target temperature. The gas flow system may also be programmable, and the diffusion bonding chamber 202 may include one or more pressure sensors. The furnace 206 can also be raised to a target temperature at a target rate. In some embodiments, the furnace 206 is operably coupled to a computing device. The computing device can execute one or more stored recipes (which may be predefined or operator-defined) that control conditions such as the furnace 206 and the gas flow system. The diffusion bonding chamber 202 can maintain a high temperature while performing diffusion bonding of the metal bodies 212A-B. In some embodiments, the temperature is between 50% and 90% of the absolute melting temperature of the material comprising the first and second metal bodies. In some embodiments, the temperature is between 60% and 80% of the absolute melting temperature of the material comprising the first and second metal bodies. In some embodiments, the temperature is about 70% of the absolute melting temperature of the material comprising the first and second metal bodies. In some embodiments, nickel can be diffusion bonded at temperatures between 1000°F and 2300°F, between 1400°F and 2000°F, about 1700°F, or any sub-range of these values. As used herein, "about" indicates a range around the indicated value, e.g., ±10% of that value.

[0027]

[0034] The diffusion bonding chamber 202 may include an opening 210. One or more metal bodies 212A-B, on which the bonding layer 214 is formed, can be inserted into the diffusion bonding chamber 202. The method for depositing the bonding layer 214 is described in more detail in Figures 3-6. Subsequently, a press 215 can be used to apply pressure and compress the metal bodies 212A-B together. The press 215 (also called a punch) applies pressure while the furnace 206 heats the metal bodies 212A-B and the bonding layer 214. Note that only one upper press 215 is shown. However, in some embodiments, a lower press that presses in the opposite direction to the upper press 215 may also be used. In some embodiments, pressure is applied to the metal bodies, reducing the overall thickness of the metal bodies by 0.1% to 5%. In some embodiments, pressure is applied to the metal bodies, reducing the overall thickness of the metal bodies by approximately 1%. Heat and pressure cause the bonding 214 and the pure metal bodies 212A-B to form a single diffusion bond, such as a component of the processing chamber. In some embodiments, the heat and pressure are maintained for several hours. In some embodiments, the heat and pressure are maintained for at least 5 hours. In some embodiments, the heat and pressure are maintained for at least 10 hours. In some embodiments, the heat and pressure are maintained for approximately 2e4 hours.

[0028]

[0035] In some embodiments, conventional techniques are unsuitable for manufacturing chamber components. In some conventional systems, components with complex internal structures can be manufactured using brazing techniques. Brazing involves placing a thin foil of a low-melting-point material between two metal bodies, heating the assembly to melt the foil, and joining the two metal bodies. Such techniques may not be applicable when the components are used in high-temperature applications, especially if the intended use of the components requires temperatures high enough to melt (or weaken) the joining material. In diffusion bonding systems such as system 200, the material used as the bonding layer 214 may be a material suitable for high-temperature environments. In some embodiments, the material used as the bonding layer 214 may have a higher melting temperature than the materials of the metal bodies 212A-B. Furthermore, brazing materials often contaminate the internal structure of the parts. Brazing materials often do not have high corrosion resistance.

[0029]

[0036] In some embodiments, the metal bodies 212A-B may be composed of substantially pure materials (e.g., the same substantially pure materials). In some embodiments, the metal bodies 212A-B may be composed of substantially pure nickel. The bonding layer 214 may be composed of metals, alloys, nonmetals, etc., to create a concentration gradient to promote diffusion and to eliminate interlayer interfaces of the diffusion-bonded article. In some embodiments, the bonding layer 214 may be composed of a material such that atoms of the material can substitute for atoms in the lattice containing the metal bodies 212A-B. For example, the metal bodies 212A and 212B may each be composed of pure nickel, and the material of the bonding layer 214 may be selected such that atoms can be exchanged between the materials of the metal bodies 212A-B and the material of the bonding layer 214. Atoms diffused from the bonding layer 214 can occupy lattice positions in the metal bodies 212A-B, for example, via substitutional diffusion bonding. Gold and copper are examples of materials that can substitute for nickel atoms in a nickel lattice. The material of the bonding layer 214 may be selected so that the material penetrates the lattice structure of the metal bodies 212A-B, for example, via interstitial diffusion bonding. For example, materials such as aluminum, boron, or titanium can diffuse bond with nickel by diffusing so that the bonding material penetrates the nickel atomic lattice, thereby eliminating the interlayer boundary. The material of the bonding layer 214 may be selected so as to facilitate diffusion by introducing a concentration gradient using an alloy. For example, the metal bodies 212A-B may be substantially composed of pure nickel, and the bonding layer 214 may be composed of a nickel alloy. In some embodiments, the bonding layer 214 may contain phosphorus. In some embodiments, the bonding layer 214 may be electroless nickel plating. The bonding layer 214 may be a thin layer of material. In some embodiments, the deposited bonding layer may be less than 10 μm, less than 5 μm, or less than 1 μm thick. Atoms in the bonding layer 214 may move (e.g., by diffusion) to the metal bodies 212A and 212B during the diffusion bonding process, and atoms in the metal bodies 212A and 212B may move to the bonding layer 214.The finished article may have no boundaries between layers, or more precisely, a concentration gradient of materials, from a substantially pure metal region of the first metal body to a region of mixed material, and back to a pure metal region of the second metal body.

[0030]

[0037] The bonding layer 214 can be applied to the surface of the metal bodies 212A and / or 212B using any method suitable for depositing a layer of material on a surface, including electroplating, vapor deposition (e.g., physical vapor deposition such as sputtering or evaporation, chemical vapor deposition such as atomic layer deposition, etc.), ion-assisted vapor deposition, plasma deposition, electroless plating, or other appropriate techniques. Figures 3–6 show some exemplary systems that may be used to deposit thin films on the surface of articles.

[0031]

[0038] An exemplary architecture of a deposition system 300 for carrying out aerosol deposition according to several embodiments is shown. The system 300 can be used to apply various coatings to components of a processing apparatus. The system 300 can be used to apply coatings of many types of materials, including polymer coatings (e.g., high dielectric strength coatings), ceramic coatings (e.g., plasma-resistant coatings), coatings containing multiple components (e.g., polymer phase and ceramic phase), or other types of coatings. The system 300 may be used to deposit precursor materials that react to form a coating on the surface of a metal body, for example, in aerosol-assisted chemical vapor deposition. The system 300 includes a deposition chamber 302. The deposition chamber may include a stage 304 for mounting the component to be coated 306 (e.g., a metal body 212 in Figure 2). The ambient pressure in the internal space 303 of the chamber 302 can be reduced via a vacuum system 308 coupled to the internal space 303 through an exhaust port 309 defined in the body of the chamber 302. The aerosol chamber 310 contains coating powder for coating the component 306, such as polymer powder, metal oxide powder, powder mixture, or reactants for forming a thin layer by chemical vapor deposition. In some embodiments, the material may be introduced in different ways, for example, by co-spraying a liquid with a carrier gas through a nozzle 314. The aerosol chamber 310 is coupled to a gas container 312. The coating material in the aerosol chamber 310 may be in the form of a fine powder, for example, having particles with a particle size of several micrometers to several hundred micrometers. The carrier gas flows from the gas container 312 through the aerosol chamber 310 into the internal space 303. The carrier gas pushes the coating powder through the nozzle 314, feeding the coating powder onto the component 306 to form a coating.

[0032]

[0039] Component 306 may be a component used for semiconductor manufacturing. Component 306 may be a component of an etching reactor, thermal reactor, semiconductor processing chamber, etc. Examples of possible components include a lid, substrate support, processing kit ring, chamber liner, nozzle, showerhead, wall, base, gas distribution plate, etc. Component 306 can be formed from materials such as aluminum, silicon, quartz, metal oxide, ceramic compound, polymer, or composite material.

[0033]

[0040] In some embodiments, the surface of component 306 may be polished to reduce the surface roughness of component 306. Reducing surface roughness can improve the thickness and uniformity of the coating. In some embodiments, the surface roughness is reduced to a level lower than the target thickness of the coating layer. In some embodiments, the surface of the metal body may be cleaned to remove, for example, a metal oxide layer, before applying the bonding layer. The metal oxide layer (or other surface contaminants) can be removed using any suitable technique, such as acid cleaning or sputtering. In some embodiments, not all areas of component 306 are coated. Areas of component 306 that are not bonded (e.g., areas not adjacent to the bond, such as channels or voids inside the finished product) can be masked, shielded, or removed from areas accessed by aerosol powder. In some embodiments, the coating material can be removed from uncoated areas after coating.

[0034]

[0041] The component 306 may be mounted on the stage 304 of the deposition chamber 302 during coating deposition. The stage 304 may be a movable stage (e.g., an electric stage) that can be moved by one, two, or three dimensions and / or rotated by one or more dimensions, so as to facilitate coating of the component 306 with the coating powder extruded from the nozzle 314. For example, the stage 304 can be moved to coat different parts or sides of the component 306. The nozzle 314 can be selectively directed at specific parts of the component 306 from various angles and directions.

[0035]

[0042] In some embodiments, the deposition chamber 302 may be evacuated using a depressurization system 308. Providing a depressurized environment in the internal space 303 can facilitate the application of the coating. For example, when the internal space 303 is under reduced pressure, the coating powder extruded from the nozzle 314 faces less resistance as it moves to the component 306. The coating powder may then collide with the component 306 more regularly and at a higher speed, which can promote adhesion to the component 306, accelerate coating formation, and reduce waste coating material.

[0036]

[0043] The gas container 312 contains a pressurized carrier gas. Available pressurized carrier gases include inert gases such as argon, nitrogen, and krypton. The pressurized carrier gas moves under pressure from the gas container 312 to the aerosol chamber 310. As the pressurized gas moves from the aerosol chamber 310 to the nozzle 314, the carrier gas pushes a portion of the coating powder from the aerosol chamber 310 towards the nozzle 314.

[0037]

[0044] In some embodiments, system 300 can be used to deposit a single material on one or more surfaces of a component 306. In some embodiments, system 300 can be used to deposit multiple materials on a component 306. In some embodiments, a polymer layer containing multiple polymers can be deposited on a component 306. In some embodiments, a ceramic layer containing multiple ceramic materials can be deposited on a component 306. In some embodiments, a material containing a polymer phase and a ceramic phase can be deposited on a component 306. In some embodiments, multiple coating precursors can be deposited. Multiple materials can be co-deposited by supplying a mixture of powder materials to an aerosol chamber 310. In an alternative embodiment, two or more aerosol chambers are coupled to a pressurized gas and nozzles 314, each able to supply material to the nozzles 314 separately. In an alternative embodiment, multiple nozzles can receive material from multiple aerosol chambers coupled to a pressurized carrier gas. In these embodiments, multiple materials can be deposited simultaneously. In some embodiments, different materials can be deposited sequentially. In some embodiments, a reaction is carried out to produce a material for coating. In some embodiments, the coated metal body may be cured (e.g., UV curing, oven curing, etc.) to facilitate a reaction that forms the target coating.

[0038]

[0045] When the carrier gas that pushes the suspension of coating powder enters the deposition chamber 302 from the nozzle 314, the coating powder is pushed toward the component 306. In some embodiments, the carrier gas is pressurized so that the coating powder is pushed toward the component 306 at a speed between 150 m / s and 500 m / s. In some embodiments, the particle size of the coating powder and the pressure of the carrier gas can be adjusted to match the target velocity distribution of the coating powder.

[0039]

[0046] In some embodiments, the nozzle 314 is formed to be wear-resistant. Due to the movement of coating powder passing through the nozzle 314 at high speed, the nozzle 314 can wear and deteriorate rapidly. The nozzle 314 can be formed in a shape and material that reduces wear.

[0040]

[0047] In some embodiments, upon impact with the component 306, the coating powder particles are broken and deformed by kinetic energy, creating a layer that adheres to the component 306. As the application of the coating powder continues, the particles bond with themselves to form a coating or film. The coating on the component 306 continues to grow through continuous collisions of the coating powder particles on the component 306. In some embodiments, the particles mechanically collide with each other and with the substrate at high speed under reduced pressure, breaking into smaller fragments rather than melting, forming a high-density layer. In some embodiments, the crystalline structure of the coating powder particles in the aerosol chamber 310 is maintained throughout the application to the component 306. In some embodiments, particle melting may occur when kinetic energy is converted into thermal energy. In some embodiments, aerosol deposition may be carried out at room temperature or between 15°C and 35°C. In some embodiments, the component 306 does not need to be heated, and the aerosol application process may not significantly increase the temperature of the component 306. Such applications can be used to coat assemblies that may be damaged in high-temperature environments. For example, a component formed by bonding multiple parts together with a bonding layer that melts at low temperatures can be damaged during the deposition process, which takes place at high temperatures. As a further example, a component formed from multiple parts of different materials with different thermal expansion properties can be damaged during deposition because the parts expand at different rates and to different sizes. Such components are less susceptible to damage from coating at ambient temperatures.

[0041]

[0048] In some embodiments, aerosol deposition may be carried out at high temperatures. In some embodiments, the component 306 may be heated before or during aerosol deposition. Such heating may facilitate the melting of the coating powder. In some embodiments, after deposition has occurred, the component 306 may be placed in an oven to heat the component and the coating material for a certain period of time. The temperature of the component 306 and the coating may rise, causing the coating to partially or completely melt. The coating may be allowed to flow over the surface of the component 306, for example, to allow the coating to reach new areas on the surface of the component 306 in order to improve the uniformity of the coating.

[0042]

[0049] In some embodiments, the coated components may be subjected to post-coating processes. For example, a ceramic coating may be polished or ground after application to component 306. The coated components may be subjected to other post-coating processes, such as heat treatment. In some embodiments, heat treatment forms a coating interface between the coating and the component. For example, applying an yttria (Y2O3) coating over an alumina (Al2O3) component can form a yttrium-aluminum-garnet (YAG) layer, which can aid adhesion and further protect the component. The barrier layer can reduce the occurrence of delamination, chipping, flaking, peeling, etc. Heat treatment may also change the chemical composition of the coating. For example, a yttria / alumina double coating may be converted to a YAG coating by heat treatment.

[0043]

[0050] Figures 4A and 4B show mechanisms and apparatus for carrying out deposition techniques using energy particles according to several embodiments. Figure 4A shows a deposition mechanism applicable to various deposition techniques using energy particles, such as ion-assisted deposition (IAD). Exemplary IAD methods include deposition processes incorporating ion collisions, such as evaporation in the presence of ion collisions (e.g., activated reaction deposition (ARE)) and sputtering, to form coatings as described herein. Any IAD method can be carried out in the presence of reactive gas species such as O2, N2, and halogens.

[0044]

[0051] As shown in the figure, a thin coating layer 415 is formed by the accumulation of a deposit material 402 in the presence of energy particles 403, such as ions. The deposit material 402 contains atoms, ions, radicals, or mixtures thereof. The energy particles 403 may collide and compress as the thin final coating layer 415 is formed.

[0045]

[0052] In one embodiment, IAD is used to form a thin coating layer 415, as already described elsewhere in this specification. Figure 4B is a schematic diagram of an IAD deposition apparatus. As shown, a material source 450 supplies a flux of deposition material 452 for deposition onto an article 460, while an energy particle source 455 supplies a flux of energy particles 453, both of which collide with the article 460 throughout the IAD process. The energy particle source 455 may be oxygen or other ion sources. The energy particle source 455 may also supply inert radicals, neutral atoms, and other types of energy particles such as nano-sized particles coming from a particle source (e.g., from plasma, a reactive gas, or a material source providing the deposition material). The IAD can utilize one or more plasmas or beams to supply the material and energy ion sources. Reactive species may also be supplied during the deposition of the coating.

[0046]

[0053] In the IAD process, energy particles 453 can be controlled by an energy ion (or other particle) source 455, independently of other deposition parameters. Depending on the energy (e.g., velocity), density, and incidence angle of the energy ion flux, the composition, structure, crystal orientation, and grain size of the thin protective layer can be manipulated. Additional adjustable parameters are the temperature of the article during deposition and the deposition duration. Ionic energy is broadly classified into low-energy ion-assisted and high-energy ion-assisted. In high-energy ion-assisted deposition, ions are projected at a higher velocity than in low-energy ion-assisted deposition. Generally, superior performance has been demonstrated with high-energy ion-assisted deposition. The substrate (article) temperature during deposition is broadly classified into low temperatures (about 120-150°C in some embodiments) and high temperatures (about 270°C in some embodiments).

[0047]

[0054] Figure 5 shows a schematic diagram of a plasma spray deposition apparatus 500 used in several embodiments of a thermal spray deposition technique. The plasma spray deposition apparatus 500 may include a casing 502 that houses a nozzle anode 506 and a cathode 504. The casing 502 allows a gas flow 508 to flow through the plasma spray apparatus 500 between the nozzle anode 506 and the cathode 504. An external power supply can be used to apply a potential between the nozzle anode 506 and the cathode 504. This potential generates an arc between the nozzle anode 506 and the cathode 504, igniting the gas flow 508 and generating plasma gas. The ignited plasma gas flow 508 generates a high-speed plasma plume 514 directed from the nozzle anode 506 towards the article 520.

[0048]

[0055] The plasma spraying apparatus 500 can be installed in a chamber or an atmospheric booth. In some embodiments, the gas stream 508 may be a gas or mixed gas, including but not limited to argon, nitrogen, hydrogen, helium, and combinations thereof. In some embodiments in which the spraying system is used to perform slurry plasma spraying, the plasma spraying apparatus 500 may include one or more fluid lines 512 for delivering slurry to the plasma plume 514. In some embodiments, a particle stream 516 is generated from the plasma plume 514 and pushed toward the article 520. Upon impact with the article 520, the particle stream forms a coating 518.

[0049]

[0056] Figure 6 shows a schematic diagram of an electroplating system for applying a bonding layer coating according to several embodiments. System 600 includes a cathode 602 and an anode 604 extending into a container 606. The container 606 contains a solution in contact with the cathode 602 and anode 604. This solution contains ions of a salt containing the material of the anode 604. For example, if the anode is composed of copper, the solution may be a solution of a soluble copper salt such as copper sulfate. In some embodiments, the anode material may resist electrochemical oxidation and instead produce byproducts in the solution.

[0050]

[0057] The DC power supply 610 draws electrons from the anode 604 and deposits them on the cathode 602. Positively charged metal ions in the solution 608 are attracted to the cathode. Metal atoms are deposited on the cathode 602 in a coating layer 612 from the solution 608. In this way, a coating layer 612 of material from the solution 608 is created on the surface of the cathode 602. In some embodiments, the material of the anode 604 replenishes the ions in the solution 608.

[0051]

[0058] In some embodiments, articles produced by diffusion bonding are made from multiple metal bodies composed of substantially pure metal (e.g., at least 99.9% pure metal). The metal bodies may be formed into specific shapes by machining or other means, for example, by machining the multiple metal bodies to be bonded to form channels or other complex geometric dimensions layer by layer. In some embodiments, the surfaces of the metal bodies (e.g., the surfaces to be bonded) are cleaned. Cleaning may include removing oxide layers from the surfaces of the metal bodies (e.g., removing oxide layers before applying the bonding layer). Areas not to be bonded (or areas not to be plated with the bonding layer material) may be masked. Common masking materials include tape, foil, lacquer, wax, etc. The metal bodies are then used as anodes in an electroplating system such as system 600 to generate thin layers of bonding material on the unmasked portions of the metal bodies. In systems where the anode material is different from the plating material (e.g., the anode material does not replenish metal ions in the solution), metal salts may be added to solution 608 as the electroplating progresses. Subsequently, the metal bodies to be joined can be assembled so that they have a joining material between them, placed in a diffusion bonding system (e.g., system 200 in Figure 2), and joined together to form a single article (e.g., a single component of a manufacturing system).

[0052]

[0059] In some embodiments, a bonding layer can be deposited using electroless plating. In some embodiments of the electroless plating process, a uniform layer of nickel-phosphorus alloy is deposited on the surface of a solid substrate. Unlike electroplating, electroless plating typically does not pass an electric current through the material to be plated. Depending on the application, electroplating may deposit a non-uniform layer of material due to non-uniform current density that can result from the shape of the cathode. Electroless plating may not be subject to such limitations.

[0053]

[0060] Electroless plating involves immersing the object to be plated in an ionic solution. The object may be machined, cleaned, masked, etc., before plating. The ionic solution contains a nickel cation source and a reducing agent. In some embodiments, the solution contains nickel sulfate and hypophosphate ions (e.g., sodium hypophosphate). A reaction occurs that produces solid nickel, elemental phosphorus, orthophosphate, protons, and molecular hydrogen. This reaction deposits a layer of nickel-phosphorus alloy on the surface of the object to be plated. Electroless plating can use nickel as a catalyst and is suitable for coating the surface of a pure nickel body with a nickel alloy, creating a concentration gradient and promoting atomic diffusion in the diffusion bonding process.

[0054]

[0061] This is a flowchart of Method 700 for producing diffusion-bonded articles composed of substantially pure metal according to several embodiments. In block 702, a first metal body and a second metal body are formed. The metal bodies can be formed from substantially pure metal. In some embodiments, the metal bodies are composed of pure nickel. In some embodiments, the first and second metal bodies are formed from a pure metal sheet. The composition of the first and second metal bodies is the same. Forming the metal bodies includes, for example, machining channels, voids, or other dimensional shapes to form one or more metal bodies.

[0055]

[0062] In block 704, a first surface of the first metal body is prepared for the application of a bonding layer. The bonding layer to be applied has a second composition different from the compositions of the first and second metal bodies. Its surface is bonded to the second metal body by diffusion bonding. Preparation of the first surface may include cleaning the surface. In some embodiments, contaminants are removed from the surface. Contaminants include organic materials, inorganic materials, metal oxides, etc. In some embodiments, contaminants are removed using solvents such as organic solvents, acids, and bases. In some embodiments, the surface is cleaned using sputtering or another method for removing material from a solid. Preparation of the first surface may include masking areas that are not to be bonded, for example, masking channels or other machined features, or masking sides or areas that are not in contact with the second metal body.

[0056]

[0063] In block 706, a bonding layer is applied to a first surface of a first metal body. The bonding layer contains a second chemical composition different from the first chemical composition. The bonding layer is applied to the first surface using any technique suitable for depositing a thin layer of material on the surface. The bonding layer can be applied by, for example, physical vapor deposition, chemical vapor deposition, electroplating, electroless plating, atomic layer deposition, molecular layer deposition, ion-assisted vapor deposition, etc. In some embodiments, the bonding layer may be less than 10 μm thick. In some embodiments, the bonding layer may be less than 1 μm thick. In some embodiments, the bonding layer may be less than 100 μm thick. In some embodiments, the bonding layer may be about 10 nm thick (e.g., ±10%).

[0057]

[0064] In block 708, the metal bodies (e.g., a first metal body and a second metal body) are arranged such that the bonding layer lies between the first surface of the first metal body and the second surface of the second metal body. In some embodiments, many metal bodies are joined together to produce a product. In some embodiments, many pure metal bodies may be laminated so that the coated bonding layer is scattered between the pure metal bodies. In some embodiments, the article may consist of alternating layers of pure metal bodies and bonding layers.

[0058]

[0065] In block 710, a diffusion-bonded article is produced by performing a diffusion bonding procedure on the metal bodies and bonding layers. Diffusion bonding is achieved by applying pressure and temperature to both metal bodies for a sufficient amount of time to bond the first metal body to the second metal body. The diffusion bonding system and technique are described in detail with reference to Figure 2.

[0059]

[0066] Figures 8A and 8B show cross-sectional views of exemplary articles 800A and 800B formed from substantially pure metal bodies using diffusion bonding according to several embodiments. Articles 800A and 800B may be any of a variety of components, including manufacturing components, chamber components, etc. In some embodiments, articles 800A and 800B are shower heads. The substantially pure metal body 802 is composed of a pure metal (e.g., the same metal with a purity of 99.9% or higher). In some embodiments, the metal body 802 is composed of nickel. Prior to diffusion bonding, one or more metal bodies 802 may have been molded, machined, cleaned, surface oxides removed, and / or otherwise prepared for diffusion bonding (e.g., the surface was polished to increase the diffusion area). Also, one or more metal bodies 802 may have a thin layer of material added to facilitate diffusion bonding by forming a concentration gradient between the pure metal body 802 and the bonding layer 804.

[0060]

[0067] The bonding layer 804 may be composed of several types of materials. The bonding layer 804 may be composed of atoms that can replace atoms in the metal lattice of the metal body 802. In some embodiments, materials such as gold and copper can replace nickel atoms in the lattice of the nickel metal body. In some embodiments, the bonding layer 804 may be composed of atoms that are interstitial within the lattice of the metal body 802. Materials such as aluminum, boron, or titanium may be interstitial within the lattice of nickel atoms. In some embodiments, the bonding layer 804 may be composed of an alloy of the material of the metal body 802. Nickel-phosphorus alloys, such as those produced by electroless nickel plating, can be used as the bonding layer 804 because they can produce a concentration gradient.

[0061]

[0068] Figure 8A is a representation of article 800A after the deposition of bonding layer 804, before the diffusion bonding process is performed. Article 800A as depicted contains separate layers, but once diffusion bonding is performed, atoms are exchanged between the layers (e.g., from metal body 802 to bonding layer 804, and from bonding layer 804 to metal body 802). The finished product may include stepwise changes in composition, rather than clear boundaries, such as composition or concentration gradients.

[0062]

[0069] Figure 8B is a representation of article 800B after the diffusion bonding process has been performed. Article 800B may not contain a clear interface between the metal bodies. Article 800B may contain a region 806 of essentially the same material as the metal body 802 (e.g., the same region of the article before diffusion bonding). Atoms of the metal body 802 and the bonding layer 804 may have exchanged, diffused, etc., so that a clear interface between the layers no longer exists. Instead, the bonding layer 804 can be replaced with a transition region 808. In the transition region 808, a spatial gradient of concentration exists. Near region 806, the transition region 808 may consist of a composition similar to that of the pure metal body 802. The composition of the portion of article 800B further from region 806 may be even more similar to the composition of the bonding layer 804, for example, an alloy of the materials of the metal body 802 and the bonding layer 804, or the concentration of the bonding layer 804 material may be higher than in the surrounding region.

[0063]

[0070] The foregoing description provides numerous specific details, such as examples of specific systems, components, and methods, to give a good understanding of some embodiments of the present invention. However, it will be apparent to those skilled in the art that at least some embodiments of the present invention can be carried out without these specific details. In other examples, well-known components or methods are not described in detail or are presented in simple block diagram form to avoid unnecessarily obscuring the invention. Thus, the specific details shown are merely illustrative. Certain embodiments, even if different from these exemplary details, are considered to be within the scope of this disclosure.

[0064]

[0071] Throughout this specification, any reference to “a particular embodiment” or “an embodiment” indicates that a specific feature, structure, or characteristic described in relation to that embodiment is included in at least one embodiment. Therefore, even if the phrases “in a particular embodiment” or “in a particular embodiment” appear in various places throughout this specification, they do not necessarily all refer to the same embodiment. In addition, the term “or” is intended to mean inclusive, rather than exclusive. Where the terms “about” or “approximately” are used herein, this is intended to mean that the presented nominal values ​​are accurate within ±10%.

[0065]

[0072] Although the steps of the methods described herein are illustrated and described in a specific order, the order of the steps of each method may be changed so that certain steps are performed in reverse order, or that certain steps are performed at least partially concurrently with other steps. In another embodiment, the instructions for separate steps or substeps may be intermittent and / or alternating.

[0066]

[0073] It should be understood that the above description is illustrative and not limiting. Many other embodiments will become apparent to those skilled in the art upon reading and understanding the above description. Therefore, the scope of the present invention shall be determined by reference to the accompanying claims and the entire scope of equivalents to which such claims are granted.

Claims

1. It is a method, The method involves applying a bonding layer having a thickness of 100 nm or less and containing a first chemical composition to a first surface of a first metal body having a second chemical composition, wherein the second chemical composition is different from the first chemical composition and is resistant to a target plasma environment, the second chemical composition is pure nickel with a purity of at least 99.99%, and the first chemical composition includes an alloy of nickel; The arrangement involves positioning the second metal body having the second chemical composition relative to the first metal body such that the bonding layer is between the first surface of the first metal body and the second surface of the second metal body, wherein the first and second metal bodies are resistant to diffusion bonding, and the bonding layer promotes diffusion bonding of the second metal body to the first metal body; Heating the first metal body and the second metal body to temperatures between 50% and 90% of the absolute melting temperature of the first chemical composition; Applying pressure to press the second metal body against the first metal body; A method comprising forming a showerhead for a substrate processing chamber configured to provide the target plasma environment for plasma processing by generating a diffusion junction between the second metal body and the first metal body in response to heating and applying pressure for a certain period of time, wherein generating the diffusion junction involves the migration of atoms from the bonding layer to the first metal body, the atoms that have migrated from the bonding layer to the first metal body either replace atoms in the lattice of the first metal body or penetrate into interstitial positions of the lattice of the first metal body, and the diffusion junction exhibits a concentration gradient from pure metal to a mixed material region and back to pure metal, and does not have a distinct bonding layer.

2. The method according to claim 1, wherein the purity of the first metal body and the purity of the second metal body are 99.99% or higher.

3. The method according to claim 1, wherein the thickness of the bonding layer is 10 nm or less.

4. Applying the aforementioned bonding layer Performing physical gas-phase deposition; Performing chemical vapor deposition; Performing electroplating; Perform electroless plating; Performing atomic layer deposition; or Perform ion-assisted deposition. The method according to claim 1, comprising at least one of the following.

5. The process further includes preparing the first surface of the first metal body before applying the bonding layer, and preparing the first surface is Removal of organic surface contaminants; Removal of inorganic surface contaminants; Polishing the first surface; or Removing the metal oxide layer from the first surface. The method according to claim 1, comprising one or more of the above.

6. The method according to claim 1, further comprising masking a region of the first metal body before applying the bonding layer, wherein the masked region is not adjacent to the diffusion bond.

7. The method according to claim 1, further comprising forming the first metal body before applying the bonding layer.

Images