Sprinkler with air gap isolation plenum and overhead isolation gas distributor

Abstract

A showerhead for independently delivering different, mutually reactive process gases to a wafer processing space is provided. The showerhead includes a first gas distributor having a plurality of plenum structures separated from each other by gaps, and a second gas distributor positioned above the first gas distributor. An isolation gas from the second gas distributor can be made to flow downward onto the first gas distributor and through the gaps between the plenum structures of the first gas distributor, thereby establishing an isolation gas curtain that prevents process gases released from each plenum structure from parasitically depositing on the plenum structures providing other gases.

Description

[0001] Incorporated by Reference

[0002] The PCT application form is filed concurrently with this specification as a part of this application. Each application from which this application claims the benefit of priority as identified in the concurrently filed PCT application form is incorporated herein by reference in its entirety and for all purposes. Background Art

[0003] Many semiconductor processing operations are performed in sealed semiconductor processing chambers in which semiconductor wafers or other substrates are supported on a wafer support or pedestal beneath a gas distributor, often referred to as a "showerhead." Discussed herein are novel showerhead designs for use in semiconductor processing equipment, particularly in semiconductor processing equipment in which there may be sequential flows of multiple different types of semiconductor processing gases, such as is the case in atomic layer deposition (ALD) and other processes. Summary of the invention

[0004] The details of one or more implementations of the subject matter described in this specification are set forth in the accompanying drawings and the description that follows. Other features, aspects, and advantages will become apparent from the description, drawings, and claims.

[0005] In some implementations, a device may be provided that includes a first gas distributor and a second gas distributor. The first gas distributor may include: a plurality of plenum structures and a plurality of groups of gas distribution ports, each group of gas distribution ports being connected to a corresponding plenum structure, and each plenum structure including a corresponding plenum volume. The plurality of groups of gas distribution ports may include a first group of first gas distribution ports and a second group of second gas distribution ports, and the plurality of plenum structures may include a first plenum structure including a first plenum volume and a second plenum structure including a second plenum volume. The first gas distribution port may be connected to the first plenum structure and configured to direct gas flowing from the first plenum volume through the first gas distribution port along a first average direction, and the second gas distribution port may be connected to the second plenum structure and configured to direct gas flowing from the second plenum volume through the second gas distribution port along a second average direction, the second average direction having a component aligned with the first average direction. When viewed along the first average direction, the first plenum structure may be spaced apart from the second plenum structure by at least a first gap. The second gas distributor may include an isolation gas plenum volume and a plurality of isolation gas ports in fluid communication with the isolation gas plenum volume, and the second gas distributor may be positioned such that the isolation gas ports are between the isolation gas plenum volume and the first gas distributor. The isolation gas ports may be configured to cause gas flowing from the isolation gas plenum volume through the isolation gas ports to flow toward the first gas distributor and through the first gap.

[0006] In some further implementations, the first gap may be at least 2 mm. In some further implementations, the first gap may be between 2 mm and 40 mm.

[0007] In some further implementations, the first plenum structure may include a first spiral tube, and the second plenum structure may include a second spiral tube. The first spiral tube and the second spiral tube may be located in the same plane, may have substantially similar pitches, and may be arranged in a radial array relative to each other.

[0008] In some further implementations, the first air-filled chamber structure and the second air-filled chamber structure can each be processed from a plate of solid material, and the edges of the first air-filled chamber structure and the second air-filled chamber structure can be rounded with a radius of at least 1 mm.

[0009] In some further implementations, the apparatus may further include a plurality of structural supports, each structural support connecting two or more of the plenum structures together.

[0010] In some further implementations, the plenum structures may be arranged in an equally spaced radial array about a common central axis.

[0011] In some further implementations, each plenum structure may include one or more tubular structures extending along the corresponding one or more paths. In some further such implementations, each tubular structure may have an outer cross-section at the cross-sectional position in a plane perpendicular to the corresponding one or more paths, and such outer cross-section may be one or more of a circular cross-section, an oblong cross-section, an elliptical cross-section, and a teardrop cross-section. In some further or alternative implementations, the first gap may vary along the one or more paths.

[0012] In some further implementations, the gas distribution ports connected to each plenum volume may be arranged along the corresponding one or more paths.

[0013] In some further implementations, each plenum volume in the first gas distributor can be fluidly connected to a corresponding gas inlet through a corresponding fluid channel, and the corresponding gas inlet is positioned so that the second gas distributor is interposed between the corresponding gas inlet and the first gas distributor. In some further such implementations, the first gas distributor and the second gas distributor can be configured to move relative to each other along the first average direction.

[0014] In some further implementations, each plenum structure may include a corresponding gas inlet, and the gas distribution ports arranged along each path may be spaced apart from each other at a distance that decreases with increasing flow path distance from the corresponding gas inlet.

[0015] In some further implementations, each plenum structure may include a corresponding gas inlet, and the size of the gas distribution ports arranged along each path may generally increase with increasing flow path distance from the corresponding gas inlet.

[0016] In some further implementations, the second gas distributor may have a back plate, a peripheral side wall and a panel that define the volume of the isolation gas inflation chamber; the peripheral side wall may be between the back plate and the panel, and the isolation gas port may be provided by a plurality of holes passing through the panel and distributed throughout the panel.

[0017] In some further implementations, the apparatus may further include: a semiconductor processing chamber; and a wafer support positioned within the semiconductor processing chamber; in such implementations, both the first gas distributor and the second gas distributor may be centered above the wafer support.

[0018] In some further implementations, the apparatus may further include: an isolation gas source configured to provide an isolation gas to the isolation gas plenum volume; a first process gas source configured to provide a first process gas to the first plenum volume; and a second process gas source configured to provide a second process gas to the second plenum volume. In such implementations, the first process gas and the second process gas may be different, and the isolation gas may be non-reactive to both the first process gas and the second process gas.

[0019] In some implementations, a method of using an apparatus such as the above apparatus can be provided. In such a method, one or more process gases can flow from the first gas distributor. During such process gas flows, a barrier gas can simultaneously flow through the second gas distributor. During some such process gas flows, the first process gas can flow out of the first plenum volume, and the second process gas can flow out of the second plenum volume, and the first process gas and the second process gas can be reactive with each other.

[0020] In some further implementations, details of one or more implementations of the subject matter described in this specification are described in the accompanying drawings and the following description. Other features, aspects, and advantages will become apparent from the description, drawings, and claims. It should be noted that the relative sizes of the following drawings may not be drawn to scale. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Various implementations disclosed herein are illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings in which like reference numerals refer to similar elements.

[0022] Figure 1 is a top partial view of an exemplary first gas distributor according to the present disclosure.

[0023] Figure 2 is a side cross-sectional view of an exemplary first gas distributor and a second gas distributor according to the present disclosure.

[0024] Figure 3 is a side cross-sectional view of an exemplary first gas distributor and a second gas distributor according to the present disclosure.

[0025] Figure 4 FIG. 4 is a top partial view of another exemplary first gas distributor according to the present disclosure.

[0026] Figure 5 For Figure 4 An isometric view of an exemplary first gas distributor similar to the first gas distributor shown.

[0027] Figure 6 For Figure 5 An isometric view of another exemplary unitary first gas distributor that is similar to the first gas distributor shown but is of unitary construction.

[0028] Figure 7 for Figure 6 An isometric partial cross-sectional view of an exemplary monomeric first gas distributor.

[0029] Figure 8 is a top partial view of another exemplary first gas distributor according to the present disclosure.

[0030] Fig. 9 is a side view of an exemplary gas distribution system incorporating concepts discussed in the present disclosure.

[0031] Fig.10 for Fig. 9 Bottom view of an exemplary gas distribution system.

[0032] Fig.11 for Fig. 9 A perspective, partially cut-away view of an exemplary gas distribution system.

[0033] Fig.12 for Fig. 9 A side view of an exemplary gas distribution system of FIG. 1 with the second gas distributor in a raised state.

[0034] Fig.13 for Fig. 9 A side view of an exemplary gas distribution system of FIG. 1 with the second gas distributor in a lowered state.

[0035] Fig.14 For installation in semiconductor processing chambers Fig. 9 Side view of an exemplary gas distribution system.

[0036] The drawings depict only one example of the concepts discussed herein, and it can be readily appreciated that the concepts discussed herein can be implemented in numerous alternative implementations, all of which are considered to be within the scope of the present disclosure. DETAILED DESCRIPTION

[0037] Importantly, the concepts discussed herein are not limited to any single aspect or implementation discussed herein, nor are they limited to any combination and / or permutation of such aspects and / or implementations. Furthermore, each of the aspects of the present invention and / or its implementations may be employed alone or in combination with one or more of the other aspects and / or their implementations. For the sake of brevity, many of these permutations and combinations will not be discussed and / or described separately herein.

[0038] The inventors of the present invention have conceived a novel showerhead design for use in semiconductor processing operations involving the alternating application of two or more different types of precursors or other semiconductor processing gases. For example, in atomic layer deposition (ALD), a semiconductor wafer may be dosed using repeated cycles of two separately applied precursors (e.g., precursor A and precursor B). As precursor A flows through the wafer, a layer of precursor A may adsorb on the semiconductor wafer. Precursor A is then flushed from the processing chamber using a non-reactive purge gas (leaving adsorbed precursor A), after which precursor B is flowed through the semiconductor wafer, whereupon precursor B reacts with precursor A in a self-limiting manner to form a monomolecular thick layer of material. Unreacted precursor B is then purged from the chamber using a non-reactive purge gas, and the process is repeated as needed to deposit the desired material thickness layer by layer.

[0039] Since the precursors used in the ALD operation react with each other immediately after mixing, they are usually kept physically and generally temporarily separated from each other in the showerhead / processing chamber. For example, an ALD showerhead may have two sets of gas distribution ports distributed on the panel, and each set of gas distribution ports is fluidly connected to different internal plenum volumes of the showerhead, each of which is supplied with a different precursor gas. However, the inventors of the present invention have determined that such a conventional showerhead arrangement is susceptible to undesirable reactions between the two precursors on the surface of the panel facing the wafer. More specifically, it was found that a portion of the precursor gas leaving such a panel tends to flow back or slightly form eddies in the area around each gas distribution port, causing the precursor to be adsorbed on the panel itself in addition to the semiconductor wafer. As a result, the panel will experience undesirable deposition, which will accumulate over time and repeated wafer processing operations, and will adversely affect the performance of the showerhead, and may cause damage or contamination to the wafer processed using the showerhead. In order to address this accumulation problem, it is necessary to perform a cleaning operation or other treatment required to restore the showerhead to its original dimensional state. Such an operation carries undesirable costs both in terms of the cost of performing such an operation and in terms of the production downtime experienced while the showerhead is cleaned. In addition, the films deposited in some ALD operations may be resistant to cleaning using atomic fluorine (which is a cleaning gas commonly used to remove undesirable deposited materials from semiconductor manufacturing equipment), or other cleaning techniques (such as dry etching, which is common), which means that the component to be cleaned must be removed and replaced or subjected to mechanical cleaning operations (such as grinding, machining, etc.) before reinstallation.

[0040] It should be noted that the above examples have been discussed with respect to atomic layer deposition, but the principles and concepts discussed herein are generally applicable to any semiconductor processing operation or tool involving two or more gases or reactants that are kept isolated from each other until flowing through a semiconductor wafer, for example, atomic layer etching (ALE), plasma enhanced chemical vapor deposition (PECVD), chemical vapor deposition (CVD), plasma enhanced atomic layer deposition (PEALD), etc.

[0041] To address such issues, the inventors of the present invention have conceived a novel showerhead design comprising a first gas distributor in which each precursor is routed through a separate plenum structure that is substantially in-plane with the other plenum structures in the first gas distributor, but separated from each adjacent plenum structure by a gap (e.g., an air gap) (it should be understood that "air gap" in this sense means a gap that is not occupied by solid material, rather than a gap that has actual "air" therein - most semiconductor processing operations are performed in a vacuum or low pressure environment, and such environments are generally kept as free of atmospheric air as possible). Such a showerhead additionally comprises a second gas distributor having an isolation gas plenum structure having a plurality of isolation gas ports positioned above the first gas distributor to flow isolation gas through the first gas distributor and through the air gaps between the plenum structures in the first gas distributor. When this operation is performed, a substantially continuous curtain of isolation gas is generated that flows between the various precursor gases released from the various plenum structures in the first gas distributor. This isolation gas curtain is used to prevent the precursors released from the plenum structure in the first gas distributor from reaching the surfaces of other plenum structures in the first gas distributor, thereby avoiding possible mixing of various precursors on the surface of the first gas distributor.

[0042] In addition, in some implementations, the vertical distance between the first gas distributor and the second gas distributor can be adjusted so that the flow of the isolation gas has sufficient time to develop into a laminar flow when it reaches the gas distribution port of the inflatable chamber structure in the first gas distributor, thereby reducing the possibility of eddy currents or backflows near the surface of the inflatable chamber structure (and thereby reducing the risk of precursor adsorption on the surface of the inflatable chamber structure).

[0043] It should be understood that isolation gas is used herein to refer to a gas that is non-reactive with the various precursors that may flow through the plenum structure of the showerhead. Such isolation gases may include, for example, argon, nitrogen, and ammonia.

[0044] These concepts are discussed in more detail below with reference to several exemplary implementations.

[0045] Figure 1 FIG. 1 is a top partial view of an exemplary first gas distributor according to the present disclosure. Figure 1 1, the first gas distributor 102 is shown as having a first plenum structure 106 defining a first plenum volume 116 fluidly connected to a plurality of first gas distribution ports 126 that allow a first process gas to flow through the first plenum volume 116 in a first average direction (e.g., downwardly into the first process gas in this example). Figure 1The first gas distributor 102 also includes a second plenum structure 108, which defines a second plenum volume 118 fluidly connected to a plurality of second gas distribution ports 128, the plurality of second gas distribution ports 128 allowing a second process gas to flow out of the second plenum structure 108 in a second average direction having a component aligned with the first average direction; in many such implementations, the first average direction and the second average direction may be substantially the same. In this example, both the first plenum structure 106 and the second plenum structure 108 are spiral-shaped, for example, each consisting of a tube that is bent or curled into a spiral. As shown, the first plenum structure 106 can be supplied with a first process gas through a first gas inlet 162, and the second plenum structure 108 can be supplied with a second process gas through a second gas inlet 164. For structural purposes, the plenum structures of the first gas distributor 102 can be connected to each other by one or more structural supports 160, which can be brazed, welded, or otherwise attached to the plenum structures. The structural supports can be kept relatively thin (e.g., on the order of several millimeters) to avoid significantly hindering or interfering with the flow of the isolation gas from the second gas distributor through the first gas distributor.

[0046] Figure 1 The first and second plenum structures 106, 108 shown in FIG. 1 are arranged in a radial array around a common center point. Thus, the first and second plenum structures 106, 108 are separated from each other by a first gap 140 that extends between the first and second plenum structures 106, 108 to substantially the entire length of either of the first and second plenum structures 106, 108. Figure 1In some implementations, the first gap 140 is maintained constant along the entire length of the first plenum structure 106 and the second plenum structure 108, but in other implementations, the first gap 140 may be variable, for example, expanding or narrowing in size as the distance from the center of the first gas distributor increases. The first gap 140 may, for example, have one or more of the following values: between 2 mm and 40 mm in some implementations, between 4 mm and 36 mm in some implementations, between 6 mm and 32 mm in some implementations, between 8 mm and 28 mm in some implementations, between 10 mm and 24 mm in some implementations, between 12 mm and 20 mm in some implementations, and between 14 mm and 16 mm in some implementations. Such a first gap range may be applicable to any of the implementations discussed herein.

[0047] The gas distribution ports shown distributed along the length of each tube are equally spaced from each other in this example. In some implementations, the gas distribution ports can be configured in different ways, such as having gradually increasing or decreasing spacing, or gradually increasing or decreasing diameters as the flow path distance between the gas inlet of the gas plenum structure and the gas distribution port increases, to adjust the flow rate of the gas from each individual gas distribution port, and thus adjust the uniformity of gas distribution across the surface of the semiconductor wafer.

[0048] The first plenum structure 106 and the second plenum structure 108 may have various cross-sectional shapes. In some implementations, the first plenum structure 106 and the second plenum structure 108 may have a hollow square or squarish (square with rounded corners) shape, such as cross-section 136A. In other implementations, the first plenum structure 106 and the second plenum structure 108 may have a circular cross-section such as cross-section 136B or an elliptical cross-section 136C. In other implementations, the first plenum structure 106 and the second plenum structure 108 may have a lachrymiform, or tear-drop shaped cross-section 136D (in some implementations, they may have opposite cross-sections, with the larger diameter portion configured upward and the smaller diameter portion configured downward; the gas distribution port in this example would be located in the smaller diameter portion configured downward).

[0049] Figure 2 FIG. 1 is a side cross-sectional view of an exemplary first gas distributor and a second gas distributor according to the present disclosure. Figure 2 In the device, set Figure 1The apparatus also includes a first gas distributor 202 similar to the first gas distributor of the present invention; the apparatus also includes a second gas distributor 204 positioned above the first gas distributor 202. The first gas distributor 202 includes a first plenum structure 206 and a second plenum structure 208. The first plenum structure 206 defines a first plenum volume 216 and has a plurality of first gas distribution ports 226 connected thereto, the plurality of first gas distribution ports 226 being in fluid communication with the first plenum volume 216. Similarly, the second plenum structure 208 defines a second plenum volume 218 and has a plurality of second gas distribution ports 228 connected thereto, the plurality of second gas distribution ports 228 being in fluid communication with the second plenum volume 218. The first gas distribution ports 226 and the second gas distribution ports 228 are generally configured to cause gas to flow along a first average direction 238 (e.g., downward).

[0050] like Figure 2 As shown, the second gas distributor 204 may include a face plate 276, a peripheral side wall 274, and a back plate 268 that define (in major part) an isolation gas structure 214 that includes an isolation gas plenum volume 224. The back plate 268 may include an isolation gas inlet 270 through which isolation gas may flow into the isolation gas plenum volume 224 and then flow out through a plurality of isolation gas ports 234.

[0051] from Figure 2 2, the first plenum structure 206 is separated from the second plenum structure 208 by a first gap 240, and the outlet planes of the first gas distribution port 226 and the second gas distribution port 228 are offset from the outlet plane of the isolation gas port 234 by a second gap 242. The isolation gas (dashed arrow) can flow through the isolation gas plenum volume 224, out through the isolation gas port 234, and through the first gas distributor 202. Due to the circular cross-sectional shape of the first and second plenum structures 206 and 208, the isolation gas can flow around them without much (if any) turbulence or backflow, thereby reducing the chance of process gas flowing from the first gas distributor 202 being deposited on their surfaces. In some implementations, the second gap 242 can have a value in the range of 6 mm to 30 mm, but other implementations can have other second gap values ​​if desired. Such values ​​are also applicable to other implementations discussed herein.

[0052] Figure 3is a side cross-sectional view of an exemplary first gas distributor and a second gas distributor according to the present disclosure. The first gas distributor 302 is similar to the first gas distributor 202, and the discussion of the first gas distributor 202 provided above is also applicable to the first gas distributor 302. The second gas distributor 304 has a different design from the second gas distributor 204 and is substantially similar to the first gas distributor 302. However, the second gas distributor can have a single plenum volume 324 (rather than two separate plenum volumes), which is defined by the isolation gas plenum structure 314. For example, the isolation gas plenum structure 314 can be substantially the same in appearance as the double-helix first plenum structure 106 and the second plenum structure 108, except that the two plenum structures are fluidly connected at the center, or can be fluidly separated from each other but fed with the same isolation gas from two separate inlets. The isolation gas can flow out through the isolation gas port 334 and flow onto / through the first gas distributor 302.

[0053] It should be understood that while the foregoing examples use a spiral plenum structure for the first gas distributor, any of a variety of plenum structures may be utilized to implement the concepts discussed herein. However, the various plenum structures used must a) be configured to substantially distribute the gas over the wafer surface and b) substantially have a gap maintained between them and any adjacent plenum structures (for providing a different type of process gas) when viewed along a first average direction (e.g., along a vertical direction).

[0054] Figure 4 FIG. 4 is a top partial view of another exemplary first gas distributor according to the present disclosure. Figure 4 The first gas distributor 402 has two arcuate, comb-shaped plenum structures: a first plenum structure 406 and a second plenum structure 408, each of which includes an arcuate channel that distributes gas from a first gas inlet 462 and a second gas inlet 464 to "finger" channels, respectively, which are staggered with each other and include a first gas distribution port 426 and a second gas distribution port 428, respectively. The arcuate channels and finger channels of the first plenum structure 406 provide a first plenum volume 416, while the arcuate channels and finger channels of the second plenum structure 408 provide a second plenum volume 418. It can be seen that a first gap 440 is maintained between the first plenum structure 406 and the second plenum structure 408, however the first gap 440 varies in size at many locations (e.g., near the tip of each "fingers").

[0055] Figure 5 For Figure 4 An isometric view of an exemplary first gas distributor similar to the first gas distributor shown. Figure 5In the embodiment, like the first gas distributor 402, the first gas distributor 502 includes a first plenum structure 506 and a second plenum structure 508, each of which supplies gas via a corresponding first gas inlet 562 and a second gas inlet 564. Figure 5 Implementations of this type may be achieved, for example, by machining each plenum structure separately (e.g., into an upper half and a lower half to allow machining of the internal plenum volume; the two halves may then be brazed or otherwise processed to join them together as a single piece of each plenum structure). Such a structure would be stiffer and more stable due to the potentially thicker wall thickness and shorter cantilever length. In some implementations, such plenum structures may be additively manufactured (e.g., using direct laser metal sintering or a similar process) to manufacture each plenum structure as a single, monolithic component. Clearly, the gas distributors discussed herein may be made by any of a variety of different machining or manufacturing processes.

[0056] Figure 6 For Figure 5 An isometric view of another exemplary unitary first gas distributor that is similar to the first gas distributor shown but is of unitary construction. Figure 7 for Figure 6 An isometric partial cross-sectional view of an exemplary monomer first gas distributor. Figure 6 and 7 In, with Figure 5 The only difference is that the first gas distributor 502' includes a plurality of structural supports 560 that bridge between the two plenum structures to form a single, connected first gas distributor 502'. It should be understood that even though the first gas distributor 502 is a single connected component, the first plenum structure 506 and the second plenum structure 508 are still separated along their entire length by the first gap 540. The structural supports 560 should be understood as not being considered as part of either plenum structure (even if connected thereto), but rather as a link or connecting structure that bridges between the two plenum structures.

[0057] Figure 8 FIG. 4 is a top partial view of another exemplary first gas distributor according to the present disclosure. Figure 8 The first gas distributor 802 shown in FIG. Figure 1482. The first gas distributor 802 is substantially the same as that shown in , but includes two additional plenum structures. Thus, the first gas distributor 802 includes a first plenum structure 806, a second plenum structure 808, a third plenum structure 810, and a fourth plenum structure 812, which respectively define a first plenum volume 816, a second plenum volume 818, a third plenum volume 820, and a fourth plenum volume 822. Each plenum volume is provided with process gas via a corresponding gas inlet and distributes the process gas onto the semiconductor wafer (whose approximate footprint is indicated by the dashed boundary 482) via a plurality of gas distribution ports. Thus, for example, the first gas-filled chamber volume 816 is provided with a first process gas via a first gas inlet 862 and then the first process gas is distributed via a first gas distribution port 826, the second gas-filled chamber volume 818 is provided with a second process gas via a second gas inlet 864 and then the second process gas is distributed via a second gas distribution port 828, the third gas-filled chamber volume 820 is provided with a third process gas via a third gas inlet 866 and then the third process gas is distributed via a third gas distribution port 830, and the fourth gas-filled chamber volume 822 is provided with a fourth process gas via a fourth gas inlet 868 and then the fourth process gas is distributed via a fourth gas distribution port 832.

[0058] In the first gas distributor 802, each plenum structure is supported relative to each other by a structural support 860, which can be welded, brazed, or otherwise connected to each plenum structure, thereby providing rigidity and support to the combined first gas distributor 802 while rarely, if ever, interfering with the downward flow of isolation gas from a second gas distributor (not shown), which is positioned above the first gas distributor 802. Isolation gas from the second gas distributor can flow between the plenum structures through the first gaps 840 present between each adjacent pair of plenum structures, thereby providing a continuous curtain of isolation gas between each plenum structure. These isolation gas curtains can generally "wall off" each plenum structure from gas flowing from adjacent plenum structures, thereby preventing such gases from mixing and forming undesirable deposition products on the underside of the plenum structures. The barrier gas flow may also be used to reduce or prevent backflow of process gases from the plenum structures, thereby preventing or mitigating adsorption of these process gases on the underside of the plenum structures in the first place.

[0059] Fig. 9 is a side view of an exemplary gas distribution system incorporating concepts discussed in the present disclosure. Fig.10 for Fig. 9 Bottom view of an exemplary gas distribution system. Fig.11 for Fig. 9 A perspective, partially cut-away view of an exemplary gas distribution system.

[0060] like Fig. 9 As can be seen in FIG. 1 , an apparatus 900 is provided that includes a first gas distributor 902 and a second gas distributor 904. The first gas distributor 902 includes a first plenum structure 906 that is provided with a first process gas via a tube, wherein the tube has a first riser section 952 and a first radial section 956 that are fluidly connected to a first gas inlet 962. Similarly, the first gas distributor 902 includes a second plenum structure 908 that is provided with a second process gas via a tube, wherein the tube has a second riser section 954 and a second radial section 958 that are fluidly connected to a second gas inlet 964. The process gas flowing into the first plenum structure 906 and the second plenum structure 908 can flow out of these respective plenum structures through corresponding first gas distribution ports 926 and second gas distribution ports 928, respectively. When viewed along a first average direction 938 (e.g., downward), the first plenum structure 906 and the second plenum structure 908 can be spaced apart from each other by a first gap 940. The first average direction 938 may be defined, for example, by an average flow direction of gas exiting the first gas distributor, or more generally may be defined as being substantially vertical.

[0061] The first plenum structure 906 and the second plenum structure 908 may be selectively supported relative to each other by structural supports 960, which may be, for example, thin (e.g., 0.1" ± 0.05") metal strips that are welded or brazed to the plenum structures. In spiral-type plenum structures such as those depicted, these structural supports 960 may provide additional rigidity that may counteract sagging and bending in the toroidal structure (because the toroid is effectively a cantilever beam having a length equal to the length of the spiral, it may experience significant flexing unless intermediate supports such as structural supports 960 are provided).

[0062] The second plenum structure 908 may be, for example, a showerhead having a faceplate with a plurality of isolation gas ports 934. The second plenum structure may be supported by support columns 996, which also serve as conduits for conducting isolation gas from the isolation gas inlet 970 to the isolation gas plenum inside the second gas distributor 904 so that the isolation gas may then flow out through the isolation gas ports 934.

[0063] In the illustrated implementation, the support column 996 is a separate component from the collar 992, and the support column 996 provides a flow path to connect the first gas inlet 962 and the second gas inlet 964 with the corresponding first radial segment 956 and the second radial segment 958. This allows the second gas distributor 904 to be vertically raised or lowered relative to the first gas distributor 902, thereby increasing or decreasing the second gap 942 that exists between the outlet planes of the first gas distribution port 926 and the second gas distribution port 928 and the outlet plane of the isolation gas port 934. A seal 994 may be provided to enable a gas-tight sliding interface between the support column 996 and the collar 992 to be formed.

[0064] Fig.12 for Fig. 9 A side view of an exemplary gas distribution system of FIG. 1 with the second gas distributor in a raised state. Fig.13 for Fig. 9 A side view of an exemplary gas distribution system of FIG. 1, wherein the second gas distributor is in a lowered state. As discussed above, Figure 9-11 In some implementations, the second gap 942 may be adjusted to lower or raise the second gas distributor 904 relative to the first gas distributor 902. In other implementations, the first gas distributor 902 may be movable and the second gas distributor 904 may be fixed to provide such adjustment, or both the first gas distributor 902 and the second gas distributor 904 may be vertically movable. In some other implementations, the second gap 942 may not be adjustable, for example, the second gap 942 may be fixed in size.

[0065] Thus, for example, the second gap 942 may be formed by Fig.12 The second gap 942 shown as being close to the maximum is adjusted to Fig.13 A near-minimum second gap 942' is shown (wherein the maximum and minimum values ​​are estimated based on the depicted configuration: other implementations may have other maximum and minimum values).

[0066] The apparatus discussed in this application may be part of a larger apparatus or system, such as a semiconductor processing chamber. In some implementations, several examples of apparatus implementations discussed herein may be used in a larger apparatus or system, such as a semiconductor processing tool having multiple such semiconductor processing chambers, each having its own first and second gas distributors as described herein.

[0067] Fig.14 For installation in semiconductor processing chambers Fig. 9 A side view of an exemplary gas distribution system. Fig.149, a collar 992 is installed in a semiconductor processing chamber 978 that enables the first gas distributor 902 and the second gas distributor 904 to be suspended within the semiconductor processing chamber 978 above a wafer support or pedestal 980 that can be used to support a semiconductor wafer or other substrate 982 below the first gas distributor 902. When fully installed, the first gas inlet 962 can be fluidly connected to a first process gas source 986, the second gas inlet 964 can be fluidly connected to a second process gas source 988, and the isolation gas inlet 970 can be fluidly connected to the isolation gas source 984. The flow path from each gas source to its corresponding inlet can be controlled by one or more valves so that the flow of gas into each plenum can be individually controlled.

[0068] In some implementations, a controller may be included, which may be part of the above examples. In addition to the first gas distributor and the second gas distributor discussed herein, such a system may also include a semiconductor processing device, which includes one or more processing tools, one or more chambers, one or more platforms for processing, and / or specific processing components (wafer bases, gas flow systems, etc.). These systems can be integrated with electronic devices for controlling their operation before, during, and after the processing of semiconductor wafers or substrates. The electronic device may be referred to as a "controller", which can control various components or sub-components of one or more systems. Depending on the processing requirements and / or the type of system, the controller can be programmed to control any process disclosed herein, including the delivery of process gases, temperature settings (e.g., heating and / or cooling), pressure settings, vacuum settings, power settings, radio frequency (RF) generator settings, RF matching circuit settings, frequency settings, flow rate settings, fluid delivery settings, position and operation settings, wafer transfer in and out of tools and other transfer tools and / or load locks connected to or connected to a specific system through an interface.

[0069] In general, a controller can be defined as an electronic device having various integrated circuits, logic, memory, and / or software that receive instructions, issue instructions, control operations, enable cleaning operations, enable endpoint measurements, etc. The integrated circuit can include a chip in the form of firmware that stores program instructions, a digital signal processor (DSP), a chip defined as an application specific integrated circuit (ASIC), and / or one or more microprocessors, or a microcontroller that executes program instructions (e.g., software). The program instructions can be instructions sent to the controller in the form of various individual settings (or program files) that define operating parameters for performing a specific process on or for a semiconductor wafer or system. In some embodiments, the operating parameters can be part of a recipe defined by a process engineer to complete one or more processing steps during the manufacture of one or more (kinds of) layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or dies of a wafer.

[0070] For example, in some implementations, the controller can be configured to operate a computer-operable valve (e.g., Fig.14906 and 908) to control the flow of gases from the various gas sources described above. For example, the controller may cause the isolation gas from the isolation gas source 984 to begin flowing through the isolation gas plenum volume for a predetermined time before causing the first process gas from the first process gas source 986 or the second process gas from the second process gas source 988 to begin flowing through its corresponding plenum volume, thereby establishing a stable flow in the form of an isolation gas curtain flowing through the first gap between the first plenum structure 906 and the second plenum structure 908. After achieving such a stable flow, the controller may control the valves controlling the flow of the first process gas and the second process gas so that the first process gas and the second process gas are alternately delivered to their corresponding plenum volumes. For example, the controller may cause the valve controlling the flow of the first process gas to enter an open state for a predetermined time (e.g., a few hundredths of a second to possibly several seconds) while causing a similar valve controlling the flow of the second process gas to enter a closed state during the same period of time. The controller may then cause the valve controlling the flow of the first process gas to enter a closed state, thereby stopping the flow of the first process gas into the corresponding plenum volume. In some implementations, the controller may then maintain both the valves controlling the first process gas and the second process gas in a closed state for another predetermined period of time to allow the isolation gas to isolate any resident first process gas space above the wafer. The controller may then cause the valve controlling the flow of the second process gas to enter an open state for a second period of time while causing the valve controlling the flow of the first process gas to enter or maintain a closed state. After the second process gas has been delivered for the second period of time, in some implementations, the controller may then cause both the valves controlling the first process gas and the second process gas to enter a closed state while maintaining the isolation gas valve open, thereby purging any resident second process gas space above the wafer. This cycle may be repeated multiple times until the semiconductor processing operation is completed.

[0071] In some implementations, the controller may be part of or coupled to a computer that is integrated with the system, coupled to the system, otherwise networked to the system, or a combination thereof. For example, the controller may be in the "cloud" or all or part of a wafer fab host system that may allow remote access to wafer processing. The computer may enable remote access to the system to monitor the current progress of a manufacturing operation, check the history of past manufacturing operations, check trends or performance criteria for multiple manufacturing operations, change parameters of a current process, set processing steps to follow the current process, or start a new process. In some examples, a remote computer (e.g., a server) may provide a process recipe to the system via a network (which may include a local network or the Internet). The remote computer may include a user interface that enables input or programming of parameters and / or settings, which are then sent from the remote computer to the system. In some examples, the controller receives instructions in the form of data that specify parameters for each processing step to be performed during one or more operations. It should be understood that the parameters may be specific to the type of process to be performed and the type of tool that the controller is configured to interface with or control. Thus, as described above, the controller may be distributed, for example, by including one or more discrete controllers networked together and working toward a common purpose (e.g., the process and control described herein). An example of a distributed controller for such a purpose is one or more integrated circuits on a chamber communicating with one or more integrated circuits remotely (e.g., at a platform level or as part of a remote computer), which combine to control the process on the chamber.

[0072] Example systems may include, but are not limited to, plasma etch chambers or modules, deposition chambers or modules, spin rinse chambers or modules, metal plating chambers or modules, cleaning chambers or modules, chamfer edge etch chambers or modules, physical vapor deposition (PVD) chambers or modules, chemical vapor deposition (CVD) chambers or modules, atomic layer deposition (ALD) chambers or modules, atomic layer etch (ALE) chambers or modules, ion implantation chambers or modules, track chambers or modules, and any other semiconductor processing system that may be associated with or used in the manufacture and / or preparation of semiconductor wafers.

[0073] As described above, depending on one or more processing steps to be performed by the tool, the controller can communicate with one or more other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, neighboring tools, tools located throughout the factory, a host computer, another controller, or tools used in material transport to transport wafer containers to and from tool locations and / or load ports in a semiconductor manufacturing facility.

[0074] It should be understood that, unless further defined, the term "group" refers to one or more items in a group, which does not require the presence of multiple items unless there is further language suggesting that multiple items exist. For example, "two or more items in a group" will be understood as having at least two items therein. Relatively, "one or more items in a group" will be understood as having only one item therein. Similarly, it should be understood that the term "each" can be used herein to refer to each member of a group, even if the group contains only one member. The term "each" can also be used in the same manner with an implicit group, such as when the term "group" is not used but other languages ​​imply the presence of a group. For example, "each item in one or more items" should be understood to be equivalent to "each item in one or more items in a group".

[0075] It should be understood that although the above disclosure focuses on one or more specific exemplary implementations, it is not limited to the examples discussed, but can also be applied to similar variations and mechanisms, and such similar variations and mechanisms are also considered to fall within the scope of the present disclosure.

Claims

1. An apparatus for semiconductor processing, the apparatus comprising: A gas distribution system comprising: an isolation gas distributor including an isolation gas plenum volume and a plurality of isolation gas ports in fluid communication with the isolation gas plenum volume, the isolation gas ports being configured such that when isolation gas flows through the isolation gas plenum volume and out of the isolation gas ports, the isolation gas flows in a first average direction; and A process gas distributor, which includes a plurality of process gas plenum structures, each process gas plenum structure including a corresponding process gas plenum volume fluidly connected to a corresponding plurality of gas distribution ports and having at least a portion separated from at least a portion of other process gas plenum structures by a corresponding gap when viewed along the first average direction, wherein the process gas distributor is positioned so that when the isolation gas flows from the isolation gas port of the isolation gas distributor along the first average direction, the isolation gas flows through the process gas distributor.

2. The apparatus of claim 1, wherein each gap is at least 2 mm.

3. The apparatus of claim 1, wherein each gap is between 2 mm and 40 mm.

4. The device according to claim 1, wherein: Each process gas plenum structure has a spiral shape when viewed along the first average direction.

5. The apparatus of claim 1, wherein: The plurality of process gas plenum structures include a first plenum structure and a second plenum structure, The first plenum structure comprises a first spiral tube, and the second plenum structure comprises a second spiral tube, The first helical tube and the second helical tube are located in the same plane, and The first helical tube and the second helical tube have substantially similar pitches and are arranged in a radial array relative to each other.

6. The apparatus of claim 1, wherein: The plurality of process gas plenum structures include a first plenum structure and a second plenum structure, and The first air-filled chamber structure and the second air-filled chamber structure are each processed from a plate of solid material, and the edges of the first air-filled chamber structure and the second air-filled chamber structure are rounded with a radius of at least 1 mm.

7. The apparatus of claim 1 further comprising a plurality of structural supports, each structural support connecting two or more of the process gas plenum structures together.

8. The device according to claim 7, wherein: Each process gas plenum structure is completely disconnected from the other process gas plenum structures except for one or more of the structural supports bridging between adjacent portions of two or more of the process gas plenum structures.

9. The apparatus of claim 1 wherein the process gas plenum structures are arranged in an equally spaced radial array about a common central axis.

10. The apparatus of claim 1, wherein each plenum volume in the process gas distributor is fluidly connected to a corresponding gas inlet via a corresponding fluid channel, the corresponding gas inlet being positioned such that the isolation gas distributor is interposed between the corresponding gas inlet and the process gas distributor.

11. The apparatus of claim 10, wherein the process gas distributor and the isolation gas distributor are configured to move relative to each other along the first average direction.

12. The apparatus of claim 1, wherein each plenum structure comprises one or more tubular structures extending along corresponding one or more paths.

13. An apparatus according to claim 12, wherein each tubular structure has an outer cross-section at an outer cross-section position in a plane perpendicular to the corresponding one or more paths, and the outer cross-section is selected from a group consisting of: a circular cross-section, an oblong cross-section, an elliptical cross-section, and a teardrop-shaped cross-section.

14. The apparatus of claim 12, wherein each gap varies along the corresponding one or more paths.

15. The apparatus according to claim 12, wherein: Each gap between adjacent tubular structures of the process gas plenum structure varies along a path along which the adjacent tubular structures extend.

16. The apparatus of claim 12, wherein the gas distribution ports fluidly connected to each process gas plenum volume are arranged along the corresponding one or more paths.

17. The apparatus of claim 16, wherein: Each plenum structure includes a corresponding gas inlet, and The gas distribution ports arranged along each path are spaced apart from each other at a distance that decreases with increasing flow path distance from the corresponding gas inlet.

18. The apparatus of claim 16, wherein: Each plenum structure includes a corresponding gas inlet, and The gas distribution ports arranged along each path generally increase in size with increasing flow path distance from the corresponding gas inlet.

19. The apparatus of claim 1, wherein: The isolation gas distributor has a back plate, a peripheral side wall and a face plate defining the volume of the isolation gas plenum, The peripheral side wall is between the back plate and the face plate, and The isolated gas ports are provided by a plurality of holes passing through and distributed throughout the panel.

20. The apparatus of claim 1, further comprising: Semiconductor processing chambers; and A wafer support is positioned within the semiconductor processing chamber, wherein: The process gas distributor and the isolation gas distributor are positioned within the semiconductor processing chamber and centered above the wafer support.

21. The apparatus of claim 20, further comprising: an isolation gas source configured to provide the isolation gas to the isolation gas plenum volume; a first process gas source configured to provide a first process gas to a first one of the respective process gas plenum volumes; and a second process gas source configured to provide a second process gas to a second one of the respective process gas plenum volumes, wherein: The first process gas and the second process gas are different, and The barrier gas is non-reactive to the first process gas and the second process gas.

22. The apparatus of claim 20, further comprising one or more additional gas distribution systems.

23. The apparatus of claim 1, wherein: The process gas distributor is positioned such that when the isolation gas flows from the isolation gas port of the isolation gas distributor along the first average direction, at least some of the isolation gas passes through the process gas distributor by flowing through each corresponding gap between at least the portions of the process gas plenum structure.

24. The apparatus of claim 1, wherein: When viewed along the first average direction, there are two comb-shaped process gas filling chamber structures, each comb-shaped process gas filling chamber structure having finger channels extending from the distribution channel, wherein the finger channels of one of the two comb-shaped process gas filling chamber structures are staggered between the finger channels of the other of the two comb-shaped process gas filling chamber structures.

25. The apparatus of claim 1, wherein: Each process gas plenum structure has an outer cross-section at the one or more locations of one or more of its gas distribution ports, the outer cross-section being selected from the group consisting of a circular cross-section, an oblong cross-section, an elliptical cross-section, and a teardrop-shaped cross-section.

26. A method for semiconductor processing, the method comprising: One or more process gases are caused to flow from a first gas distributor, the first gas distributor comprising: A plurality of plenum structures and a plurality of groups of gas distribution ports, each group of gas distribution ports being connected to a corresponding plenum structure, and each plenum structure comprising a corresponding plenum volume, wherein: The plurality of groups of gas distribution ports include a first group of first gas distribution ports and a second group of second gas distribution ports, the plurality of plenum structures comprising a first plenum structure comprising a first plenum volume and a second plenum structure comprising a second plenum volume, The first gas distribution port is connected to the first plenum structure and is configured to direct process gas flowing from the first plenum volume through the first gas distribution port along a first average direction, The second gas distribution port is connected to the second plenum structure and is configured to direct process gas flowing from the second plenum volume through the second gas distribution port along the first average direction, and The first plenum structure and the second plenum structure are spaced apart from each other by at least a first gap when viewed along the first average direction; and causing isolation gas to flow from a second gas distributor as process gas flows from the first gas distributor, the second gas distributor comprising an isolation gas plenum volume and a plurality of isolation gas ports in fluid communication with the isolation gas plenum volume, wherein: positioning the second gas distributor such that the isolation gas port is between the isolation gas plenum volume and the first gas distributor, and The isolation gas port is configured to flow isolation gas flowing from the isolation gas plenum volume through the isolation gas port toward the first gas distributor and through the first gap.

27. The method of claim 26, wherein: causing a first process gas to flow out of the first plenum volume through the first gas distribution port while causing a second process gas to flow out of the second plenum volume through the second gas distribution port, and The first process gas is reactive to the second process gas.

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