Single-sided anodizing of the diffuser

Abstract

An exemplary diffuser for a substrate processing chamber may include a diffuser body characterized by a first surface at an inlet side of the diffuser body and a second surface at an outlet side of the diffuser body. The diffuser body may define a plurality of apertures through a thickness of the diffuser body. The first surface may be non-anodized. The second surface may be anodized.

Description

[Technical Field]

[0001] The present technology relates to components and apparatus for glass and semiconductor substrate manufacturing. More particularly, the present technology relates to processing chamber distribution components and other substrate processing equipment. [Background technology]

[0002] Integrated circuits are made possible by processes that create intricately patterned layers of material on substrate surfaces. Creating patterned materials on a substrate requires controlled methods for material formation and removal. Chamber components often deliver process gases to the substrate to deposit films or remove materials. To promote symmetry and uniformity, many chamber components may include regular patterns of features, such as apertures, to deliver material in a manner that can improve uniformity. However, this can limit the ability to tailor recipes for on-wafer adjustments.

[0003] Therefore, there is a need for improved systems and methods that can be used to produce high quality devices and structures. These and other needs are addressed by the present technology. Summary of the Invention

[0004] An exemplary diffuser for a substrate processing chamber may include a diffuser body characterized by a first surface on an inlet side of the diffuser body and a second surface on an outlet side of the diffuser body. The diffuser body may define a plurality of apertures through a thickness of the diffuser body. The first surface may be non-anodized. The second surface may be anodized.

[0005] In some embodiments, each of the plurality of apertures may include an upper region and a lower region. The upper region and the lower region may be separated by a choke region. The choke region may be anodized. The choke region may not be anodized. The lower region may be anodized. The lower region may include a generally conical shape. The diffuser may include a side surface extending between the first surface and the second surface and joining the first surface and the second surface. The side surface may not be anodized.

[0006] Some embodiments of the present technology may include a method for anodizing one surface of a diffuser. The method may include coating a first surface of the diffuser with a polymeric material and leaving a second surface of the diffuser exposed. The first surface may be opposite the second surface. The diffuser may define a plurality of apertures through a thickness of the diffuser. The method may include applying heat to the diffuser. The method may include exposing the diffuser to a chemical bath. The method may include applying a voltage to the chemical bath to anodize the second surface of the diffuser. The method may include removing the polymeric material from the first surface.

[0007] In some embodiments, the method may include applying heat to the diffuser and then flowing a pressurized material through the apertures. Flowing the pressurized material may include one or both of bead blasting and CO2 blasting. Each of the plurality of apertures may include an upper region and a lower region. The upper region and the lower region may be separated by a choke region. Flowing the pressurized material may remove any polymer material present in the choke region of each of the plurality of apertures. Coating the first surface may include using a directional coating process to apply a polymer material onto the first surface at an angle relative to a length of each of the plurality of apertures and within a portion of each of the plurality of apertures. Removing the polymer material may include applying heat to the polymer material to soften the polymer material. Removing the polymer material may include peeling the polymer material from the diffuser. Removing the polymer material may include exposing the diffuser to a solvent. Applying a voltage to the chemical bath may include increasing the voltage from a starting voltage to a target voltage. Applying a voltage to the chemical bath may include maintaining the voltage at a target voltage for a predetermined period of time. Applying a voltage to the chemical bath may include increasing the voltage from the target voltage to an additional target voltage. Applying a voltage to the chemical bath may include maintaining the voltage at the additional target voltage for an additional predetermined period of time. The diffuser may include a side extending between and joining the first and second surfaces. The method may include coating the side with a polymeric material.

[0008] Some embodiments of the present technology may include a method of processing a substrate. The method may include flowing a precursor into a processing chamber. The processing chamber may include a diffuser and a substrate support on which the substrate is disposed. A processing region of the processing chamber may be at least partially defined between the diffuser and the substrate support. The diffuser may be characterized by a first surface and a second surface facing the substrate support and opposite the first surface. The diffuser may define a plurality of apertures through a thickness of the diffuser. The first surface may be non-anodized. The second surface may be anodized. The method may include generating a plasma of the precursor in the processing region of the processing chamber. The method may include depositing a material on the substrate.

[0009] In some embodiments, each of the plurality of apertures may include an upper region and a lower region. The upper and lower regions may be separated by a choke region. The choke region may not be anodized. The lower region may include a generally conical shape.

[0010] Such techniques can provide numerous benefits over conventional systems and techniques. For example, embodiments of the present techniques can reduce the impurity content of films and improve the threshold voltage of wafers. In addition, components can maintain desired process-to-process stability. These and other embodiments, along with many of their benefits and features, are described in more detail in conjunction with the following description and accompanying drawings.

[0011] A further understanding of the nature and advantages of the disclosed technology may be realized by reference to the remaining portions of the specification and the drawings. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 illustrates a top view of an exemplary processing system in accordance with some embodiments of the present technique. [Figure 2]1 is a schematic cross-sectional view of an exemplary plasma system in accordance with some embodiments of the present technique; [Figure 3] 1 is a schematic partial cross-sectional view of an exemplary diffuser in accordance with some embodiments of the present technology; [Figure 4] 10A-10C illustrate operations of an exemplary method for anodizing one surface of a diffuser in accordance with some embodiments of the present technology. [Figure 5A] 1 is a schematic partial cross-sectional view of an exemplary diffuser being anodized in accordance with some embodiments of the present technique; [Figure 5B] 1 is a schematic partial cross-sectional view of an exemplary diffuser being anodized in accordance with some embodiments of the present technique; [Figure 5C] 1 is a schematic partial cross-sectional view of an exemplary diffuser being anodized in accordance with some embodiments of the present technique; [Figure 5D] 1 is a schematic partial cross-sectional view of an exemplary diffuser being anodized in accordance with some embodiments of the present technique; [Figure 5E] 1 is a schematic partial cross-sectional view of an exemplary diffuser being anodized in accordance with some embodiments of the present technique; [Figure 6] 10A-10C illustrate operations of an exemplary method for anodizing a diffuser in accordance with some embodiments of the present technique. [Figure 7] 1A-1D illustrate exemplary method operations for substrate processing in accordance with some embodiments of the present technique. DETAILED DESCRIPTION OF THE INVENTION

[0013] Some figures are included as schematic diagrams. It should be understood that the figures are for illustrative purposes and should not be considered to scale unless specifically indicated to scale. Furthermore, the figures are provided as schematic diagrams to aid understanding and may not include all aspects or information compared to realistic representations and may include exaggerated details for illustrative purposes.

[0014] In the accompanying figures, similar components and / or functions may be labeled with the same reference label. Furthermore, various components of the same type may be distinguished by a letter following the reference label that distinguishes between the similar components. If only the first reference label is used herein, the description may apply to any one of the similar components having the same first reference label, regardless of the letter.

[0015] Plasma-enhanced deposition processes can energize one or more constituent precursors to promote film formation on a substrate. Any number of material films can be created to develop substrate structures, including conductive and dielectric films, as well as films that facilitate material transfer and removal. For example, hard mask films can be formed to facilitate substrate patterning while protecting and otherwise preserving underlying materials. In many processing chambers, multiple precursors can be mixed in a gas panel and delivered to the processing region of the chamber where the substrate may be placed. The precursors can be distributed across one or more components within the chamber, thereby creating a radial or lateral distribution of delivery that enhances formation or removal at the substrate surface.

[0016] As device feature sizes decrease, tolerances across the substrate surface can decrease, and differences in material properties across the film can affect device realization and uniformity. Many chambers contain characteristic process signatures that can create non-uniformities across the substrate. Temperature differences, uniformity of flow patterns, and other aspects of processing can affect the film on the substrate, potentially resulting in differences in film uniformity across the substrate of the material being created or removed. For example, one or more devices may be included within the processing chamber to deliver and distribute precursors into the processing chamber. A shield plate may be included in the chamber to provide a choke to the precursor flow, thereby increasing the residence time of the precursor at the shield plate and improving lateral or transverse distribution. A face plate or diffuser may further improve delivery uniformity within the processing region, thereby improving deposition or etching.

[0017] Some conventional diffusers have bare (non-anodized) surfaces, but such diffusers can exhibit poor run-to-run stability in terms of deposition rate and thickness uniformity during deposition processes. To address this instability, some diffusers may be anodized, thereby improving run-to-run stability in terms of deposition rate and thickness uniformity due to dielectric effects resulting from the anodization of the diffuser. However, during the anodization of the diffuser, nano-sized pores are created in the oxide film, which allows the oxide to grow thicker than would be possible under passivation conditions. The pores at the bottom of the diffuser may be covered by the seasoning and deposition films and may have no effect on the wafer. However, the pores at the top of the diffuser may remain exposed and may trap some process gases, which may later be released during subsequent deposition operations. These released gases may dope undesirable materials onto the wafer, which may adversely affect the wafer's threshold voltage and / or cause other defects.

[0018] The present technology overcomes these challenges by utilizing a diffuser in which only the bottom surface is anodized, leaving the top surface unanodized. While such a diffuser may eliminate exposed pores on the top surface, these pores trap gases that, if not eliminated, can later be released and form undesirable dopants on the film. As a result, the anodized top surface may improve run-to-run stability of deposition rate and thickness uniformity during the deposition process while maintaining wafer threshold voltage within specifications. Additionally, some embodiments of the present technology may utilize anodization techniques that increase pore size and reduce the number of pores present on the anodized diffuser surface to help reduce or eliminate any trapped gases that can later form undesirable dopants on the film and affect threshold voltage. Thus, the present technology may produce improved film deposition characteristics from wafer to wafer.

[0019] While the remainder of the disclosure routinely identifies a particular deposition process utilizing the disclosed technology, it will be readily understood that the systems and methods are equally applicable to other deposition and cleaning chambers and processes that may occur within the described chambers. Accordingly, the present technology should not be considered limited to use with only these particular deposition processes or chambers. This disclosure describes one possible system and chamber that may include lid stack components according to embodiments of the present technology, before describing additional modifications and adjustments to this system according to embodiments of the present technology.

[0020] FIG. 1 illustrates a top view of one embodiment of a deposition, etch, bake, and cure chamber processing system 100 in accordance with embodiments of the present technology. In the figure, a pair of front-opening unified pods 102 deliver substrates of various sizes that are received by a robotic arm 104 and placed in a low-pressure holding area 106 located in tandem sections 109a-109c before being placed in one of the substrate processing chambers 108a-108f. A second robotic arm 110 can be used to transfer substrate wafers from the holding area 106 to the substrate processing chambers 108a-108f and vice versa. Each substrate processing chamber 108a-108f can be equipped to perform many substrate processing steps, including the formation of stacks of semiconductor materials as described herein, in addition to plasma-enhanced chemical vapor deposition, atomic layer deposition, physical vapor deposition, etch, pre-cleaning, degassing, alignment, and other substrate processes including annealing, ashing, and the like.

[0021] The substrate processing chambers 108a-108f may include one or more system components for depositing, annealing, curing, and / or etching a dielectric or other film on a substrate. In one configuration, two pairs of processing chambers, e.g., 108c-108d and 108e-108f, may be used to deposit a dielectric material on a substrate, and a third pair of processing chambers, e.g., 108a-108b, may be used to etch the deposited dielectric. In another configuration, all three pairs of chambers, e.g., 108a-108f, may be configured to deposit a stack of alternating dielectric films on a substrate. Any one or more of the described processes may be performed in chambers separate from the fabrication system shown in different embodiments. It will be understood that additional configurations of deposition, etching, annealing, and curing chambers for dielectric films are contemplated by system 100.

[0022] 2 shows a schematic cross-sectional view of an exemplary plasma system 200 according to some embodiments of the present technique. The plasma system 200 may illustrate a pair of processing chambers 108, which may be mated to one or more tandem sections 109 and may include faceplates or other components or assemblies according to embodiments of the present technique, as described further below. The plasma system 200 may generally include a chamber body 202 having a sidewall 212, a bottom wall 216, and an interior sidewall 201 that defines a pair of processing regions 220A and 220B. Each of the processing regions 220A-220B may be similarly configured and may include identical components.

[0023] For example, processing region 220B (components of which may be included in processing region 220A) may include a pedestal 228 disposed within the processing region through a passageway 222 formed in the bottom wall 216 of the plasma system 200. The pedestal 228 may provide a heater adapted to support a substrate 229 on an exposed surface of the pedestal, such as a body portion. The pedestal 228 may include a heating element 232, such as a resistive heating element, that may heat and control the substrate temperature to a desired processing temperature. The pedestal 228 may be heated by a remote heating element, such as a lamp assembly, or any other heating device.

[0024] The body of the pedestal 228 may be coupled to the stem 226 by a flange 233. The stem 226 may electrically couple the pedestal 228 to a power outlet or power box 203. The power box 203 may include a driver system that controls the elevation and movement of the pedestal 228 within the processing region 220B. The stem 226 may also include a power interface for supplying power to the pedestal 228. The power box 203 may also include an interface for power and temperature indicators, such as a thermocouple interface. The stem 226 may include a base assembly 238 adapted to removably couple with the power box 203. A circumferential ring 235 is shown on the power box 203. In some embodiments, the circumferential ring 235 may be a shoulder adapted as a mechanical stop or land configured to provide a mechanical interface between the base assembly 238 and the upper surface of the power box 203.

[0025] A rod 230 may be included through a passage 224 formed in the bottom wall 216 of the processing region 220B and may be utilized to position substrate lift pins 261 disposed through the body of the pedestal 228. The substrate lift pins 261 may selectively space the substrate 229 from the pedestal to facilitate exchange of the substrate 229 with a robot utilized to transfer the substrate 229 to or from the processing region 220B through the substrate transfer port 260.

[0026] The chamber lid 204 may be coupled to the top of the chamber body 202. The lid 204 may house one or more precursor delivery systems 208 coupled thereto. The precursor delivery system 208 may include a precursor inlet passage 240 that may supply reactant and cleaning precursors to the processing region 220B through a gas supply assembly 218. The gas supply assembly 218 may include a gas box 248 having a shield plate 244 disposed intermediate a face plate 246. A radio frequency ("RF") source 265 may be coupled to the gas supply assembly 218 and may provide power to the gas supply assembly 218 to facilitate generation of a plasma region between the face plate 246 of the gas supply assembly 218 and a pedestal 228, which may be the processing region of the chamber. In some embodiments, the RF source may be coupled to other portions of the chamber body 202, such as the pedestal 228, to facilitate generation of the plasma. A dielectric isolator 258 may be disposed between the lid 204 and the gas supply assembly 218 to prevent conduction of RF power to the lid 204. A shadow ring 206 may be disposed around the pedestal 228 in engagement with the pedestal 228.

[0027] Optional cooling channels 247 may be formed within the gas box 248 of the gas distribution system 208 to cool the gas box 248 during processing. A heat transfer fluid, such as water, ethylene glycol, or gas, may be circulated through the cooling channels 247 to maintain the gas box 248 at a predetermined temperature. A liner assembly 227 may be positioned within the processing region 220B in close proximity to the sidewalls 201, 212 of the chamber body 202 to prevent exposure of the sidewalls 201, 212 to the processing environment within the processing region 220B. The liner assembly 227 may include a circumferential pumping cavity 225 that may be coupled to a pumping system 264 configured to evacuate gases and byproducts from the processing region 220B and control the pressure within the processing region 220B. A plurality of exhaust ports 231 may be formed on the liner assembly 227. The exhaust ports 231 may be configured to allow gas flow from the processing region 220B to the circumferential pumping cavity 225 in a manner that facilitates processing within the system 200.

[0028] FIG. 3 shows a schematic partial cross-sectional view of an exemplary faceplate or diffuser 300 according to some embodiments of the present technology. FIG. 3 may show additional details regarding components within system 200, such as for faceplate 246. It is understood that diffuser 300 may include any feature or aspect of system 200 described above in some embodiments. Diffuser 300 may be used to perform substrate processing operations, including deposition of hard mask materials as described above, as well as other deposition, removal, and cleaning operations. For example, in some embodiments, diffuser 300 may be used to deposit materials on one or more surfaces of a substrate, such as a glass substrate and / or a semiconductor substrate, such as a substrate used in a display device. Diffuser 300 may depict a partial view of a diffuser that may be incorporated into a substrate processing system, or may otherwise illustrate a view through the center of a diffuser that may be of any size and include any number of apertures. While many apertures are shown extending laterally or radially outward, it should be understood that the drawing is included solely for purposes of illustrating the embodiments and should not be considered to scale. For example, exemplary face plates may be characterized by a number of apertures along their diameter of about 20 or more apertures, about 25 or more apertures, about 30 or more apertures, about 35 or more apertures, about 40 or more apertures, about 45 or more apertures, about 50 or more apertures, or more, as further described below.

[0029] As shown, the diffuser 300 may be included in any number of processing chambers, including the system 200 described above. The diffuser 300 may be included as part of a gas inlet assembly, such as with a gas box and a shielding plate. For example, the gas box may define or provide access into the processing chamber. A substrate support may be included in the chamber and configured to support a substrate for processing. A shielding plate may be included in the chamber between the gas box and the substrate support. The shielding plate may include or define a number of apertures therethrough. In some embodiments, the shielding plate may be characterized by an increased central conductance. For example, in some embodiments, a subset of apertures proximate or extending around a central region of the shielding plate may be characterized by a larger aperture diameter than apertures radially outward from the central region. This may, in some embodiments, increase the central flow conductance. The component may include any of the features described above with respect to similar components, as well as various other modifications also encompassed by the present technology.

[0030] The diffuser 300 may be positioned within the chamber between the shield plate and the substrate support, as described above. The diffuser 300 may be characterized by a body having a first surface 305 and a second surface 310 that may be opposite the first surface. In some embodiments, the first surface 305 may be on the inlet side of the diffuser 300 and may face the shield plate, gas box, or gas inlet into the processing chamber. The second surface 310 may be on the outlet side of the diffuser 300 and may be positioned to face the substrate support or substrate within the processing region of the processing chamber. For example, in some embodiments, the second surface 310 of the diffuser 300 and the substrate support may at least partially define the processing region within the chamber. The diffuser 300 may be characterized by a central axis 315 that may extend vertically through the midpoint of the face plate and may be coaxial with a central axis through the processing chamber.

[0031] The diffuser 300 may define a plurality of apertures 320 defined through the faceplate, extending from the first surface through the second surface. Each aperture 320 may provide a fluid path through the faceplate, and the apertures may provide fluid access to the processing region of the chamber. Depending on the size of the diffuser and the size of the apertures, the diffuser 300 may define any number of apertures through the plate, such as about 1,000 or more apertures, about 2,000 or more apertures, about 3,000 or more apertures, about 4,000 or more apertures, about 5,000 or more apertures, about 6,000 or more apertures, or more. As described above, the apertures may be included in a set of rings extending outward from the central axis, and may include any number of rings as described above. The rings may be characterized by any number of shapes, including circular or elliptical, as well as any other geometric pattern, such as rectangular, hexagonal, or any other geometric pattern that may include apertures distributed among multiple radially outward rings. The apertures may be uniformly or staggered and may be spaced about 10 mm or less center-to-center. The apertures may also be spaced about 9 mm or less, about 8 mm or less, about 7 mm or less, about 6 mm or less, about 5 mm or less, about 4 mm or less, about 3 mm or less, or less apart.

[0032] The rings may be characterized by any geometric shape as described above, and in some embodiments, the apertures may be characterized by a scaling function of the apertures per ring. For example, in some embodiments, the first aperture may extend through the center of the diffuser, such as along the central axis as shown. The first ring of apertures may include any number of apertures, such as about 4 to about 10 apertures, which may extend around the central aperture and may be evenly spaced around a geometric shape extending through the center of each aperture. Additional rings of any number of apertures may extend radially outward from the first ring and may include a number of apertures, which may be a function of the number of apertures in the first ring. For example, the number of apertures in each successive ring may be characterized by the number of apertures in each corresponding ring according to the formula XR, where X is the base number of apertures and R is the corresponding ring number. The base number of apertures may be the number of apertures in the first ring, or in some embodiments, may be some other number, as further described below when the first ring has an increased number of apertures. For example, for an exemplary diffuser having five apertures distributed around the first ring, if five is the base number of apertures, the second ring may be characterized by 10 apertures (5) x (2), the third ring may be characterized by 15 apertures (5) x (3), and the twentieth ring may be characterized by 100 apertures (5) x (20). This may continue for any number of rings of apertures, as described above, such as up to, greater than, or about 50 rings. In some embodiments, each aperture of a plurality of apertures across a diffuser may be characterized by an aperture profile, which may be the same or different in embodiments of the present technology.

[0033] Apertures 320 may include any profile or any number of sections with different profiles, such as those shown. For example, in some embodiments, apertures 320 may be approximately cylindrical. In other embodiments, some or all of apertures 320 may have more complex profiles. For example, in one non-limiting example as shown, each aperture 320 may include an upper region 322 and a lower region 324. Upper region 322 and lower region 324 may be separated by a choke region 326, which may have a smaller diameter (or average diameter) than upper region 322 and lower region 324. Upper region 322 may extend from first surface 305 of diffuser 300 or may extend partially through diffuser 300. In some embodiments, upper region 322 may extend at least about halfway through, or 75% of, the thickness of the diffuser between first surface 305 and second surface 310. Upper region 322 may be characterized by a substantially cylindrical profile, as shown. By substantially, we mean that the profile may be characterized by a cylindrical profile, but may take into account machining tolerances and part variations, as well as a certain margin of error. Upper region 322 may transition to an optional choke region 326, which may act as a choke for diffuser 300 and increase flow distribution or uniformity. As shown, choke region 326 may include a taper and / or step transitioning from the diameter of upper region 322 to the narrower diameter of choke region 326. The diameter of choke region 326 may be smaller than the diameter of upper region 322. For example, the diameter of upper region 322 may be more than 1.5 times, more than 1.75 times, more than 2.0 times, more than 2.25 times, more than 2.5 times, or more than the diameter of choke region 326. Choke region 326 then widens into lower region 324. The lower region 324 may extend from partially through the diffuser to the second surface 310. The lower region 324 may extend through less than half the thickness of the diffuser 300, or may extend less than half or about halfway through the diffuser 300, for example.Lower region 324, in some embodiments, may be characterized by a tapered profile from second surface 310 and, if it includes choke region 326, may extend to include a cylindrical and / or conical portion intersecting choke region 326. Lower region 324, in some embodiments, may be characterized by a generally conical profile or a countersunk profile, among other tapered profiles. In some embodiments, the generally conical profile may include a single tapered / conical profile, while in other embodiments, the generally conical profile may include two or more regions with different degrees of taper, as shown. The maximum diameter of lower region 324 (e.g., at second surface 310) may be greater than the diameters of both upper region 322 and choke region 326. For example, the maximum diameter of lower region 324 may be more than 1.1 times, more than 1.2 times, more than 1.3 times, more than 1.4 times, more than 1.5 times, more than 1.75 times, more than 2.0 times, more than 2.25 times, more than 2.5 times, or more than the diameter of upper region 326. The maximum diameter of lower region 324 may be more than 3.5 times, more than 4.0 times, more than 4.5 times, more than 5.0 times, more than 5.25 times, or more than the diameter of choke region 326.

[0034] The conical profile of the lower region 324 of the aperture 320 may help increase the ion flux due to the pronounced hollow cathode effect of the conical section. This increased ion flux directly translates to improved deposition rates at the edge of the substrate located below the diffuser. Increased deposition at the edge of the substrate results in an overall increase in deposition uniformity and a flatter thickness profile across the substrate.

[0035] A portion of the diffuser 300 may be anodized. For example, the second surface 310 of the diffuser 300 may be anodized, while the first surface 305 (and at least the upper region 322 of each aperture 320) is not anodized. This allows the diffuser to have the benefits of a bare, anodized diffuser without any drawbacks. In particular, the anodized second surface 310 may improve run-to-run stability of deposition rate and thickness uniformity during the deposition process and eliminate nanopore formation on the first surface 305, which can adversely affect the wafer threshold voltage. In some embodiments, the lower region 324 and / or choke region 326 of each aperture 320 may be anodized along with the second surface 310; in other embodiments, the lower region 324 and / or choke region 326 of each aperture 320 may not be anodized. In embodiments in which choke regions 326 are anodized, the anodization process may be carefully controlled to ensure uniform anodization within each aperture 320 and to keep the diameter of each choke region 326 uniform and of a desired size that maintains proper and uniform flow conductance through diffuser 300. Diffuser 300 may include a side surface 312 that extends between and joins first surface 305 and second surface 310. In some embodiments, side surface 312 may be anodized, while in other embodiments, side surface 312 may not be anodized.

[0036] FIG. 4 illustrates operations of an exemplary method 400 for anodizing one surface of a diffuser according to some embodiments of the present technology. The method may produce a diffuser having a single anodized surface similar to diffuser 300 described above. Method 400 may include many optional operations that may or may not be specifically associated with some embodiments of methods according to the present technology. Method 400 may include optional operations prior to the start of method 400, or the method may include additional operations. For example, method 400 may include operations performed in a different order than illustrated. Method 400 is described in connection with FIGS. 5A-5E, which illustrate diffuser 500 (which may be similar to diffuser 300 and may be used in any processing chamber, such as processing chamber 200) being anodized according to method 400.

[0037] In some embodiments, method 400 may include, at operation 405, coating first surface 505 of diffuser 500 with polymer material 530, leaving second surface 510 of diffuser 500 exposed. A portion of each aperture 520 defined by diffuser 500 may be coated along with first surface 510. For example, an upper region 522 of each aperture 520 may be coated with polymer material 530. First surface 505 may be similar to first surface 305 and may be the top surface of diffuser 500, and second surface 510 may be similar to second surface 310 and may be the bottom surface of diffuser 500. In some embodiments, side surface 512 may be coated with polymer material 530. Polymer material 530, in some embodiments, may include a thermoplastic material (such as, but not limited to, high-density polyethylene, polyurethane, polyethylene terephthalate, etc.), which may protect the coated surface of diffuser 500 from being anodized. In some embodiments, such as that shown in FIG. 5A , coating the first surface 505 may include a directional coating application process, such as, but not limited to, 3D printing and / or spraying of a polymer material 530 onto the first surface 505 and into the upper region 522 of each aperture 520. It may be desirable to prevent the polymer material 530 from entering a choke region 526 of the aperture 520. In some embodiments, to help prevent this, one or more applicator nozzles 580 used to apply the polymer material 530 may be angled with respect to the longitudinal axis of each aperture 520 so that the polymer material emitted from the nozzle 580 is not directed toward the choke region 526. For example, the nozzle 580 may be angled so that the edge of the emitted polymer material is directed toward a lower corner and / or edge of the upper region 522. This angle may depend on the aspect ratio of the upper region 522 of the aperture 520. Nozzle 580 may be translated along one or more directions and / or rotated in one or more paths through diffuser 500 to evenly coat the desired surface of diffuser 500 .In some embodiments, the diffuser 500 may be inverted during the coating process so that the first surface 505 faces downward. Such an orientation can help prevent the polymer material 530 from flowing into the choke region 526 of each aperture 520 due to the effects of gravity. Additionally or alternatively, air (or other fluid) may be forced into the lower region 524 and choke region 526 of each aperture 520 during the coating operation. For example, the second surface 510 of the diffuser 500 may be capped or otherwise sealed, and a fluid source providing the fluid may create a positive pressure environment near the second surface 510. The positive pressure may create an airflow through the apertures 520, and particularly through the choke region 526, that is strong enough to prevent the polymer material 530 from penetrating through the choke region 526 without preventing the spray from reaching the base of the upper region 522 of the aperture 520.

[0038] As shown in FIG. 5B, coating first surface 505 may prevent polymer material 530 from reaching the base of upper region 522 completely. For example, airflow through choke region 526 and / or the angle of spray from nozzle 580 may leave some or all of the base of upper region 522 of each aperture 520 uncoated. In operation 410, heat may be applied to diffuser 500, thereby softening polymer material 530 sufficiently to flow and cover the base of upper region 522. Heat may be applied up to the softening temperature of polymer material 530. In some embodiments, the softening temperature may be between or about 100° C. and 150° C., although it will be appreciated that such temperature may depend on the polymer material used. In some instances, some of polymer material 530 may flow into choke region 526, as shown in FIG. 5C, which may lead to non-uniformity in choke region 522 during anodization. To eliminate this problem, the method may include applying heat to the diffuser and then flowing a pressurized material through the apertures. For example, bead blasting, CO blasting, sand blasting, and / or other techniques for delivering a pressurized material may be used to remove polymer material 530 from choke region 526, if present, as shown in FIG. 5D. The pressurized material may be delivered from second surface 510 of diffuser 500 to prevent the pressurized material from removing material within upper region 522 and / or first surface 505.

[0039] In operation 415, the partially coated diffuser 500 may be exposed to a chemical bath 590. For example, the diffuser 500 may be submerged in an electrolyte with the second surface 510 facing the cathode 585, as shown in FIG. 5E. In operation 420, a voltage may be applied to the chemical bath to anodize the exposed second surface 510 while leaving the coated first surface 505 unanodized. In some embodiments, the voltage may be ramped from a starting voltage (which may be zero) to a target voltage. The voltage may be maintained at the target voltage for a predetermined period of time. The target voltage may, in some embodiments, be a final voltage. By using a single target voltage step, the pore size may be increased and the pore density may be decreased in any anodized surface, thereby reducing the amount of gas that may be trapped by the pores during the deposition operation and subsequently released. Additionally, fewer pore branches are produced compared to a multi-step voltage delivery process. This may help improve the consistency of threshold voltages in wafers produced using the diffuser. In other embodiments, the target voltage may be an intermediate voltage. In such embodiments, the voltage may be increased from the target voltage to an additional, higher target voltage and maintained for an additional predetermined period of time. Such steps may be repeated any number of times to complete the anodization process. For example, in some embodiments, three target voltages may be used, but in various embodiments, the process may include one or more target voltages, two or more target voltages, three or more target voltages, four or more target voltages, five or more target voltages, ten or more target voltages, or more.

[0040] Once the second surface 510 has been anodized, the polymer material 530 may be removed from any coated surfaces in operation 425. Removing the polymer material 530 may include applying heat to the polymer material 530 to soften it. Once softened, the polymer material 530 may be peeled and / or otherwise manually removed from the surface of the diffuser 500. In some embodiments, some residue of the polymer material 530 may remain. In such cases, the diffuser 500 may be exposed to a solvent such as acetone to remove the residue. The resulting diffuser 500 may be anodized on the surfaces not coated with the polymer material 530, while the coated surfaces may remain unanodized. Such a diffuser 500 may provide the benefits of a bare and anodized diffuser without any of the drawbacks. In particular, the anodized second surface 510 may improve run-to-run stability of deposition rate and thickness uniformity during the deposition process and eliminate nanopore formation in the first surface 505, which can adversely affect the threshold voltage of the wafer.

[0041] 6 illustrates operations of an exemplary method 600 for anodizing a diffuser according to some embodiments of the present technology. The method may create a diffuser with a single anodized surface similar to diffuser 300 described above, or may create a fully anodized diffuser. Method 600 may include multiple optional operations that may or may not be specifically associated with some embodiments of methods according to the present technology. Method 600 may include optional operations before the start of method 600, or the method may include additional operations. For example, method 600 may include operations that are performed in a different order than illustrated.

[0042] Method 600 may include exposing a diffuser (which may or may not include any polymeric material coating on any surface) to a chemical bath in operation 605. In operation 610, a voltage may be applied to the chemical bath to anodize the exposed (uncoated) surface of the diffuser. The voltage may be ramped from a starting voltage (which may be zero) to a final target voltage in a single step. The voltage may be maintained at the final target voltage for a predetermined period of time. By using a single target voltage step, pore size may be increased and pore density may be reduced in any anodized surface, thereby reducing the amount of gas that may be trapped by the pores during the deposition operation and subsequently released. Additionally, fewer pore branches are produced compared to multi-step voltage delivery processes, which may help improve threshold voltage consistency in wafers produced using the diffuser.

[0043] 7 illustrates operations of an exemplary method 700 of substrate processing in accordance with some embodiments of the present technique. The method may be performed in various processing chambers, including the processing system 200 described above, which may include a diffuser in accordance with embodiments of the present technique, such as diffuser 300 or 500. Method 700 may include several optional operations that may or may not be specifically associated with some embodiments of methods in accordance with the present technique.

[0044] Method 700 may include a processing method, which may include an operation to form a hard mask film or other deposition operation. The method may include optional operations before the start of method 700, or the method may include additional operations. For example, method 700 may include operations performed in a different order than shown. In some embodiments, method 700 may include flowing one or more precursors into a processing chamber in operation 705. For example, the precursors may be flowed into a chamber such as that included in system 200, and the precursors may be flowed through one or more of a gas box, a shield, or a diffuser before delivering the precursors into the processing region of the chamber.

[0045] In some embodiments, the diffuser may be characterized by a first surface and a second surface and may define a number of apertures through the thickness of the diffuser. Any of the other diffuser characteristics described above, including any aspect of diffuser 300 or 500, may also be included, such as the second surface being anodized and the first surface remaining unanodized. In some embodiments, each aperture may include an upper region and a lower region, which may be separated by a choke region. The upper region may be unanodized, the lower region may be anodized, and the choke region may be unanodized or anodized. In some embodiments, the lower region may have a generally conical profile. In operation 710, a plasma may be generated in the precursor within the processing region, such as by providing RF power to the diffuser to generate the plasma. The material formed in the plasma may be deposited on a substrate, such as a glass and / or semiconductor substrate, in operation 715. In some embodiments, depending on the thickness of the deposited material, the deposited material may be characterized by a thickness at the edge of the substrate that is approximately the same as the thickness in the central region of the substrate. For example, the deposited material may be characterized by a thickness that is close to the edge of the substrate, with a target uniformity of less than 500 Å.

[0046] In the foregoing description, for purposes of explanation, numerous details have been set forth in order to provide an understanding of various embodiments of the present technology. However, it will be apparent to those skilled in the art that particular embodiments may be practiced without some of these details or with additional details.

[0047] While several embodiments have been disclosed, those skilled in the art will recognize that various modifications, alternative constructions, and equivalents may be used without departing from the spirit of the embodiments. Moreover, in order to avoid unnecessarily obscuring the present technology, many well-known processes and elements have not been described. Therefore, the above description should not be construed as limiting the scope of the present technology.

[0048] Where a range of values ​​is provided, unless the context clearly dictates otherwise, it is understood that each intervening value between the upper and lower limits of that range, to the smallest fraction of the unit of the lower limit, is also specifically disclosed. Any narrower range between a stated value or an unstated intervening value in a stated range and any other stated or intervening value in the stated range is included. The upper and lower limits of these smaller ranges may be independently included or excluded, and each range in which either, neither, or both of the limits are included in the smaller ranges is also encompassed within the technology, subject to any specifically excluded limits in the stated range. When a stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included.

[0049] As used in this specification and the appended claims, the singular forms "a," "an," and "the" include the plural forms unless the context clearly indicates otherwise. Thus, for example, a reference to a "heater" includes a plurality of such heaters, a reference to a "protrusion" includes one or more protrusions and equivalents thereof known to those skilled in the art, and so forth.

[0050] Additionally, the terms "comprise(s)", "comprising", "contain(s)", "containing", "include(s)", and "including" as used in this specification and the following claims are intended to specify the presence of stated features, integers, components or steps, but do not exclude the presence or addition of one or more other features, integers, components, steps, acts, or groups.

Claims

1. a diffuser body characterized by a first surface at an inlet side of the diffuser body and a second surface at an outlet side of the diffuser body; the diffuser body defining a plurality of apertures through a thickness of the diffuser body; each of the plurality of apertures having an upper region and a lower region; the upper region and the lower region are separated by a choke region; the first surface and the upper region are not anodized; the second surface and the lower region are anodized; A diffuser for a substrate processing chamber.

2. the choke region is anodized; 10. The diffuser for a substrate processing chamber of claim 1.

3. the choke region is not anodized; 10. The diffuser for a substrate processing chamber of claim 1.

4. the lower region having a generally conical shape; 10. The diffuser for a substrate processing chamber of claim 1.

5. the diffuser body includes a side extending between the first surface and the second surface and joining the first surface and the second surface; the side surface is not anodized; 10. The diffuser for a substrate processing chamber of claim 1.

6. coating a first surface of a diffuser with a polymeric material and leaving a second surface of said diffuser exposed; the first surface is opposite the second surface; the diffuser defining a plurality of apertures through a thickness of the diffuser; coating a first surface of a diffuser with a polymeric material, leaving a second surface of said diffuser exposed; applying heat to the diffuser; exposing the diffuser to a chemical bath; applying a voltage to the chemical bath to anodize the second surface of the diffuser; removing the polymeric material from the first surface; 10. A method for anodizing one surface of a diffuser, comprising:

7. applying heat to the diffuser and then flowing pressurized material through the apertures.

7. The method of anodizing one surface of a diffuser of claim 6, further comprising:

8. The flowing of the pressurized material includes bead blasting and CO ２ blasting, including either or both A method for anodizing one surface of a diffuser according to claim 7.

9. each of the plurality of apertures having an upper region and a lower region; the upper region and the lower region are separated by a choke region; flowing the pressurized material removes polymer material present in the choke region of each of the plurality of apertures. A method for anodizing one surface of a diffuser according to claim 7.

10. coating the first surface includes applying the polymeric material onto the first surface and within a portion of each of the plurality of apertures at an angle relative to a length of each of the plurality of apertures using a directional coating process. A method for anodizing one surface of a diffuser according to claim 6.

11. removing the polymeric material applying heat to the polymeric material to soften the polymeric material; and peeling the polymeric material from the diffuser. A method for anodizing one surface of a diffuser according to claim 6.

12. removing the polymeric material further comprises exposing the diffuser to a solvent; 12. A method for anodizing one surface of a diffuser according to claim 11.

13. applying a voltage to the chemical bath; increasing the voltage from a starting voltage to a target voltage; and maintaining the voltage at the target voltage for a predetermined period of time. A method for anodizing one surface of a diffuser according to claim 6.

14. applying a voltage to the chemical bath; increasing the voltage from the target voltage to an additional target voltage; and maintaining the voltage at the additional target voltage for an additional predetermined period of time.

14. A method for anodizing one surface of a diffuser according to claim 13.

15. the diffuser extending between the first surface and the second surface and including a side joining the first surface and the second surface; the method further comprising coating the side surface with the polymeric material. A method for anodizing one surface of a diffuser according to claim 6.

16. flowing a precursor into a processing chamber; The processing chamber comprises the diffuser of claim 1 and a substrate support on which a substrate is disposed; A method of processing a substrate, wherein a processing volume of the processing chamber is defined at least in part between the diffuser and the substrate support.

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