Threaded Nozzle Insert

Abstract

A threaded nozzle insert for use in a showerhead or gas distributor of a semiconductor processing tool is disclosed, comprising: a head having a first face surface and a second face surface parallel to the first face surface; a shank extending from the second face surface, a first subportion of the shank being threaded along its length and having a diameter smaller than a maximum dimension of the second face surface; and gas distribution holes extending through the head and the shank along a direction perpendicular to the second face surface.

Description

[Background technology]

[0001] Related Applications A PCT Request Form is being filed contemporaneously herewith as part of this application. Each application to which this application claims benefit or priority as identified in the contemporaneously filed PCT Request Form is incorporated herein by reference in its entirety for all purposes.

[0002] Semiconductor processing tools often include a showerhead or other gas distributor designed to receive one or more process gases through one or more corresponding inlets and then distribute the process gas(es) across a wafer to be processed through multiple gas distribution ports distributed across the underside of the showerhead (or other gas distributor). Disclosed herein are improvements to such showerhead or gas distributor systems. Summary of the Invention

[0003] The details of one or more embodiments of the subject matter described herein are set forth in the accompanying drawings and the description below. Other features, aspects, and advantages will become apparent from the description, drawings, and claims.

[0004] In some embodiments, a device may be provided that includes a head and a shank. The head may have a first face, a second face parallel to the first face and having substantially the same size and shape as the first face, and at least two side surfaces disposed between the first and second face. The shank may extend from the second face, and a first subportion of the shank may be threaded along its length and have a diameter smaller than the maximum dimension of the second face. Gas distribution holes may extend through the head and the shank in a direction perpendicular to the second face.

[0005] In some embodiments, the gas distribution holes may have a first diameter at at least one location between the first face surface and the second face surface and a second diameter greater than the first diameter where the gas distribution holes exit the stem.

[0006] In some embodiments, the first diameter can be between 0.005 inches and 0.03 inches (0.127 and 0.762 mm).

[0007] In some embodiments, the second diameter can be between 0.02 inches and 0.14 inches (0.508 and 3.556 mm).

[0008] In some embodiments, the first sub-portion of the shank may be threaded with 10-32 threads.

[0009] In some embodiments, a second sub-portion of the shank located between the first sub-portion of the shank and the second face surface may have a diameter of 0.15 inches (3.81 mm) or less.

[0010] In some embodiments, the transition between the shaft and the head may have a radius of 0.05 inches (1.27 mm) or less.

[0011] In some embodiments, the distance between the first face surface and the second face surface may be between 0.03 inches (0.0762 mm) and 0.2 inches (5.08 mm).

[0012] In some embodiments, the shank may extend from the second face surface by 0.2 inches (5.08 mm) to 0.3 inches (7.62 mm).

[0013] In some embodiments, there may be at least six sides defining a generally hexagonal shape.

[0014] In some embodiments, the second face surface may meet the six side surfaces at chamfered edges.

[0015] In some embodiments, the first face surface may meet six sides with rounded edges.

[0016] In some embodiments, the device may further comprise six curved sides, each curved side sandwiched between two of the six sides, and each curved side being concentric and of the same radius as the other curved sides.

[0017] In some embodiments, the head and shank may be formed from an aluminum alloy or ceramic.

[0018] In some embodiments, the head and shank may be formed from 6061-T6 aluminum alloy.

[0019] In addition to the embodiments described above, other embodiments apparent from the following discussion and drawings should be understood to be within the scope of the present disclosure. [Brief explanation of the drawings]

[0020] In the following description, reference will be made to the following drawings, which are not intended to be limiting in scope but are provided solely to facilitate the following description:

[0021] [Figure 1] 1 is an isometric view of an example of a threaded nozzle insert for a showerhead of a semiconductor processing tool.

[0022] [Figure 2] FIG. 2 is a front view of the example threaded nozzle insert of FIG. 1.

[0023] [Figure 3] FIG. 2 is a rear view of the example threaded nozzle insert of FIG. 1.

[0024] [Figure 4] FIG. 2 is a right side view of the example threaded nozzle insert of FIG. 1.

[0025] [Figure 5] FIG. 2 is a left side view of the example threaded nozzle insert of FIG. 1.

[0026] [Figure 6] Top view of the example threaded nozzle insert from Figure 1.

[0027] [Figure 7] FIG. 2 is a bottom view of the example threaded nozzle insert of FIG. 1.

[0028] [Figure 8] 7 is a cross-sectional view of the example threaded nozzle insert of FIG. 1 taken along the section line shown in FIG. 6.

[0029] [Figure 9] Detail of the circled area in Figure 8.

[0030] [Figure 10A] FIG. 10 is an isometric view showing an alternative threaded nozzle insert design. [Figure 10B] FIG. 10 is a cross-sectional view showing an alternative threaded nozzle insert design.

[0031] [Figure 11A] FIG. 10 is an isometric view showing another alternative threaded nozzle insert design. [Figure 11B] FIG. 10 is a cross-sectional view showing another alternative threaded nozzle insert design.

[0032] The above-described drawings are provided to facilitate understanding of the concepts discussed in this disclosure and are intended to illustrate some embodiments within the scope of this disclosure, but are not intended to be limiting; embodiments consistent with this disclosure that are not shown in the drawings are also considered to be within the scope of this disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0033] Semiconductor processing tools are often configured to distribute one or more process gases across a semiconductor wafer during one or more stages of a semiconductor processing operation. Such gas distribution is often achieved using a showerhead or gas distributor (hereinafter, the term "showerhead" will be understood to refer to showerheads and other gas distributors that may be utilized to distribute process gases within a semiconductor processing chamber). Such showerheads may have multiple gas distribution ports distributed along their underside.

[0034] In many such showerheads, the gas distribution ports are holes machined directly into the underside of the showerhead, thereby providing the showerhead with a flat or smooth underside with multiple openings extending through it.

[0035] However, other types of showerheads can be designed with removable nozzle inserts that thread into the showerhead's threaded holes. In such embodiments, the showerhead itself can have at least some gas distribution ports that terminate in larger threaded holes that are not sized to provide the desired gas delivery profile. Prior to use, such showerheads can have multiple threaded nozzle inserts threaded into such threaded holes. The use of threaded nozzle inserts can increase the manufacturing costs of such showerheads because multiple machining steps are required for each threaded hole, compared to the one or two drilling operations for gas distribution port nozzles that are machined directly into the showerhead. Additional expense is involved because the inserts themselves must be machined and then inserted. However, the use of threaded nozzle inserts also offers several important benefits. For example, such threaded nozzle inserts are removable and therefore easily replaceable, for example, if the nozzles become partially clogged due to deposition by-product accumulation or expand due to exposure to etchants. Additionally, showerheads with gas distribution port holes drilled directly into the showerhead run the risk that one or more such gas distribution holes may be too large (e.g., out of tolerance). When threaded nozzle inserts are used, any out-of-tolerance threaded nozzle inserts can be easily replaced with new threaded nozzle inserts. Such an approach avoids the potential need to discard an entire showerhead component due to out-of-tolerance.

[0036] Threaded nozzle inserts have been used in semiconductor processing systems in the past, but typically in the context of providing nozzles with exit holes that are significantly offset from the underside of a showerhead. For example, such threaded nozzle inserts may protrude from the underside of the showerhead by, for example, more than 0.5 inches (12.7 mm) (e.g., 0.75 inches (19.05 mm)) to provide a separation distance between the underside of the showerhead and the plane of the nozzle's exit holes. The present threaded nozzle inserts, in contrast, may be relatively low profile, protruding from the underside of the showerhead by only a small amount (e.g., between 0.03 inches (0.762 mm) and 0.2 inches (5.08 mm)). This allows the threaded nozzle insert to interact with a wrench or other tool that may be used to tighten or loosen the threaded connection of the threaded nozzle insert while protruding only a minimal amount into the space below the showerhead.

[0037] Figures 1-9 show various views of an example threaded nozzle insert. Figure 1 is an isometric view of an example threaded nozzle insert for a showerhead of a semiconductor processing tool. Figures 2-5 provide front, back, right side, and left side views of the threaded nozzle insert of Figure 1, while Figures 6 and 7 show top and bottom views, respectively, of the threaded nozzle insert of Figure 1. Figure 8 shows a cross-sectional view of the threaded nozzle insert of Figure 1 along the section line shown in Figure 6, and Figure 9 shows a detailed view of the circled area in Figure 8.

[0038] As described above, the threaded nozzle insert 100 is shown in FIGS. 1-9. The threaded nozzle insert 100 may have a head portion 102 and a stem portion 104. The head portion 102 may have a first face surface 106 designed to face a semiconductor wafer when the threaded nozzle insert 100 is inserted into a showerhead and used to supply process gases to the semiconductor wafer. The threaded nozzle insert 100 may further have a second face surface 108 that is parallel to the first face surface 106 and has substantially the same size and shape as the first face surface 106. Thus, the first face surface 106 and the second face surface 108 may actually be end caps of a prismatic solid (such as a substantially hexagonal prismatic solid). As mentioned above, the thickness of the head portion 102 (e.g., the distance between the first face surface 106 and the second face surface 108) may be relatively thin (e.g., less than 0.2 inches (5.08 mm)). In some such cases, this distance may be between 0.03 inches (0.762 mm) and 0.2 inches (5.08 mm).

[0039] The threaded nozzle insert 100 may further include a plurality of side surfaces 110 disposed between the first face surface 106 and the second face surface 108 (e.g., generally spanning the first face surface 106 and the second face surface 108). In some embodiments, there may be six side surfaces 110 defining a generally hexagonal shape, although other embodiments may have other numbers of side surfaces 110 (e.g., four, five, seven, or eight or more side surfaces 110). The side surfaces 110 may, for example, define the sides of a regular polygon, and in some embodiments, may include at least two side surfaces 110 that are parallel to one another. In some embodiments, the side surfaces 110 may be essentially planar (i.e., flat). In some embodiments, the threaded nozzle insert 100 may further include a plurality of curved side surfaces 112. Each curved side surface 112 may, for example, be circumferentially sandwiched between a different pair of adjacent side surfaces 110. In some such embodiments, the curved side surfaces 112 may have an arched shape that is essentially concentric and of the same radius. In some embodiments, the set of opposing side surfaces 110 may be spaced apart by a distance such as about 0.3 inches (7.62 mm) or 0.4 inches (10.16 mm). The side surfaces 110 of the head portion 102 may, in some cases, meet the first face surface 106 and / or the second face surface 108 at a chamfered and / or rounded edge. For example, the side surfaces 110 of the head portion 102 may meet the first face surface 106 at a rounded edge 128 and meet the second face surface 108 at a chamfered edge 126. Such rounded transitions may act to prevent or reduce the potential generation of particulate contaminants that could cause defects on the wafer.

[0040] The shank 104 may extend outward from the second face surface 108, away from the first face surface 106. The shank 104 may have a first sub-portion 114 threaded along its length to allow the threaded nozzle insert to be threaded into a threaded hole in a faceplate of a showerhead. The thread 130 may be, for example, a 10-32 UNF thread. In some embodiments, the shank 104 may also include a second sub-portion 116. The second sub-portion 116 may be sandwiched between the first sub-portion 114 and the second face surface 108 and may not have threads along its length. In some such embodiments, for example, in those embodiments in which the thread 130 is a 10-32 UNF thread, the second sub-portion 116 may be sized to have a diameter of 0.15 inches (3.81 mm) or less.

[0041] In some embodiments, the stem 104 may extend away from the second face surface 108 by a distance between 0.2 inches (5.08 mm) and 0.3 inches (7.62 mm), for example, about 0.25 inches (6.35 mm).

[0042] Regardless of the particular embodiment, the threaded nozzle insert 100 may further include gas distribution holes 118 extending through the threaded nozzle insert 100 (i.e., through the head 102 and the shank 104) along a direction perpendicular to the second face surface 108. The gas distribution holes 118 may be, for example, round holes having a first diameter 120, which may be the smallest diameter of the gas distribution holes 118 in the region between the first face surface 106 and the second face surface 108. In some cases, the portion of the gas distribution holes 118 having the first diameter 120 may transition to a larger second diameter 122 at a location within the threaded nozzle insert 100. For example, the gas distribution holes 118 may assume the second diameter 122 where they exit the shank 104. In some embodiments, the first diameter can be between 0.005 inches (0.127 mm) and 0.03 inches (0.762 mm), and the second diameter, if present, can be between about 0.02 inches (0.508 mm) and 0.14 inches (3.556 mm). Such a transition can be via, for example, a conical interface between two different sized portions of the gas distribution holes 118. In some embodiments, the gas distribution holes 118 can have chamfered edges where they exit the first face surface 106.

[0043] In some embodiments, the threaded nozzle insert 100 may have a radiused or rounded transition 124 where the shank 104 meets the second face surface 108. In some such embodiments, the transition 124 may be rounded with a radius of 0.05 inches (1.27 mm) or less.

[0044] The second surface 108 may be sized large enough to contact and press against the flat underside of the showerhead into which the threaded nozzle insert is threaded, thereby effectively sealing the threaded interface between the threaded nozzle insert and the showerhead to prevent potential exposure to process gases that may generate particulates when interacting with sharp edges (e.g., sharp edges of threads, etc.).

[0045] The threaded nozzle inserts discussed herein may be machined from any suitable material (e.g., a material that is chemically compatible with the process gases flowed therethrough and that can withstand the process conditions (e.g., temperatures) expected to be reached during semiconductor processing operations). For example, the threaded nozzle insert may be formed from a material such as an aluminum alloy (e.g., 6061-T6 aluminum alloy). In some other examples, the threaded nozzle insert may be formed from a ceramic (e.g., aluminum oxide).

[0046] Threaded nozzle inserts (such as those discussed herein) reduce particulate contamination, particularly when used in showerheads for some semiconductor processes. For example, when substituted for substantially longer nozzle inserts (e.g., inserts on the order of 0.5 inches (12.7 mm) in length), particulate contamination on processed wafers for a given total deposition volume has been observed to be reduced by as much as 98% compared to using longer nozzle inserts to provide a similar total deposition volume.

[0047] It is understood that threaded nozzle inserts (such as threaded nozzle insert 100) may be provided in a variety of formats. Threaded nozzle insert 100 features a hexagonal head that allows it to be twisted into place using a box wrench. However, such a configuration results in the head of the threaded nozzle insert protruding from the first side of the showerhead, as can be seen in Figure #LL. While the amount of such protrusion is relatively small, it may still be preferable to use a threaded nozzle insert that may be flush with the first side of the showerhead, or at least have a lower profile than threaded nozzle insert 100.

[0048] 10A and 10B are isometric and cross-sectional views, respectively, illustrating one example of such a threaded nozzle insert. As can be seen, the threaded nozzle insert 1000 does not have a hexagonal head, but instead has a circular head. The threaded hole in the showerhead into which the threaded nozzle insert 1000 screws may have a counterbore shape (as shown by the dashed lines in FIG. 10B ) that allows the threaded nozzle insert 1000 to screw into the showerhead so that the top surface of the head is flush or nearly flush with the first side of the showerhead. The threaded nozzle insert 1000 further includes a pair of spaced-apart spanner drive holes located on the top surface of the head on either side of the gas distribution port extending through the threaded nozzle insert 1000. Such spanner drive holes allow for the use of a spanner screwdriver or spanner driver, for example, to twist the threaded nozzle insert 1000 into place during installation (or to remove such inserts from the showerhead).

[0049] 11A and 11B are isometric and cross-sectional views, respectively, similarly illustrating another example of such a threaded nozzle insert. Threaded nozzle insert 1100 is similar to threaded nozzle insert 1000, except that instead of the spanner drive hole used in threaded nozzle insert 1000, threaded nozzle insert 1100 has a central hexagonal recess sized to accept a hex driver or Allen key, thereby allowing threaded nozzle insert 1100 to be twisted during installation. Threaded nozzle insert 1100, like threaded nozzle insert 1000, may be installed flush with a first side of the showerhead, allowing for a smoother / flatter underside of the showerhead.

[0050] Semiconductor processing tools may be controlled with a controller that can be programmed to control various processes or parameters, such as process gas supply, 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 supply settings, position and motion settings, and wafer movement into and out of the chamber. In the context of a controller used with the threaded nozzle insert disclosed herein, such a controller may control various valves that can be actuated to flow process gases through the threaded nozzle insert (e.g., via a showerhead in which the threaded nozzle insert is mounted).

[0051] Generally, a controller may 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. Integrated circuits may include chips in the form of firmware that store program instructions, digital signal processors (DSPs), chips defined as application-specific integrated circuits (ASICs), and / or one or more microprocessors or microcontrollers that execute program instructions (e.g., software). Program instructions may be communicated to the controller in the form of various individual settings (or program files) that define operational parameters for performing specific processes on or for semiconductor wafers or instructions for the system. The operational parameters, in some examples, may be part of a recipe defined by a process engineer to accomplish one or more process steps during processing of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or dies of a wafer.

[0052] In some embodiments, the controller may be part of or connected to a computer that is integrated with, connected to, or otherwise networked with the system, or a combination thereof. For example, the controller may be in the “cloud” or may be all or part of a fab host computer system that can enable remote access for wafer processing. In the context of a controller used with a semiconductor processing system, the computer may enable remote access to the system to monitor the current progress of a manufacturing operation, examine the history of past manufacturing operations, or examine trends or performance indicators from multiple manufacturing operations, to change parameters of a current process, set processing steps according to a current process, or initiate a new process. In some examples, a remote computer (e.g., a server) may provide process recipes to the system over a network (which may include a local network or the Internet). The remote computer may include a user interface that enables entry or programming of parameters and / or settings, which are communicated to the system from the remote computer. In some examples, the controller receives instructions in the form of data, where the instructions specify parameters for each of the processing steps to be performed during one or more operations. It should be understood that the parameters may be specific to the type of process being performed as well as the type of tool the controller is configured to interface with or control. Thus, as described above, the controller may be distributed, such as by having one or more separate controllers that are networked and operate toward a common purpose (such as the process and control described herein). One example of a distributed controller for such purposes is one or more integrated circuits on the chamber that communicate with one or more remotely located integrated circuits (e.g., located at the platform level or remotely as part of a remote computer) that cooperate to control the process in the chamber.

[0053] Without limitation, examples of threaded nozzle inserts according to the present disclosure may be installed in or be a part of semiconductor processing tools including plasma etch chambers or modules, deposition chambers or modules, spin rinse chambers or modules, metal plating chambers or modules, cleaning chambers or modules, bevel 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 utilized in the fabrication and / or manufacturing of semiconductor wafers.

[0054] As described above, depending on the processing step or steps being performed by the tool, the controller may communicate with one or more of other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, nearby tools, tools located throughout the factory, a main computer, another controller, or tools used in material transport to carry containers of wafers to or from tool locations and / or load ports within a semiconductor fabrication factory.

[0055] The use of ordinal numbers (e.g., (a), (b), (c), or (1), (2), (3), etc.) in this disclosure and claims should not be understood to imply any particular order or sequence unless such order or sequence is explicitly indicated. For example, where there are three steps labeled (i), (ii), and (iii), these steps may be performed in any order (or simultaneously, if not otherwise appropriate) unless otherwise indicated. For example, if step (ii) involves manipulation of an element produced in step (i), then step (ii) may be considered to be performed at some time after step (i). Similarly, if step (i) involves manipulation of an element produced in step (ii), then it should be understood that the opposite is true. It should be understood that the use of the ordinal marker "first" herein (e.g., "first item") should not be read as suggesting, implicitly or inherently, that a "second" thing (e.g., "second item") is necessarily present.

[0056] It should be understood that, when used herein, phrases such as "for each <item> of one or more <items>," "for each <item> of one or more <items>," and the like, include both single-item groups and multiple-item groups; i.e., the phrase "for each" is used in the sense used in programming languages ​​to refer to each item in any collection of items. For example, if the collection of items referred to is a single item, then "each" refers only to that single item and does not imply that there must be at least two of those items (even though dictionary definitions of "each" often define the term to refer to "every one of two or more"). Similarly, the terms "set" or "subset" should not, in and of themselves, be considered to necessarily include multiple items; it is understood that a set or subset may include only one member or multiple members (unless the context suggests otherwise).

[0057] As used herein, the term "between," when used in conjunction with a range of values, should be understood to include the first and last values ​​in the range, unless otherwise specified. For example, between 1 and 5 should be understood to include 1, 2, 3, 4, and 5, not just 2, 3, and 4.

[0058] It is understood that the examples and embodiments described herein are for illustrative purposes only, and that various modifications or alterations will occur to those skilled in the art in light thereof. Various details have been omitted for simplicity, and various design changes may be implemented. Therefore, the above examples are to be considered as illustrative and not limiting, and the disclosure is not limited to the details set forth herein, but may be modified within the scope of the disclosure.

[0059] While the above disclosure focuses on one or more particular embodiments, it should be understood that the disclosure is not limited to only the above-described examples, but is also applicable to similar modifications and mechanisms, and such similar modifications and mechanisms are also considered to be within the scope of the present disclosure.

Claims

1. 1. An apparatus comprising: a head portion having a first face surface and a second face surface parallel to the first face surface and having an outer periphery substantially the same size and shape as an outer periphery of the first face surface; a shaft portion extending from the second face surface, a first sub-portion of the shank that is threaded along its length and has a diameter that is smaller than a maximum dimension of the second face surface; a shaft portion, wherein gas distribution holes extend through the head portion and the shaft portion along a direction perpendicular to the second face surface; An apparatus comprising:

2. 10. The apparatus of claim 1, wherein the gas distribution holes have a first diameter at at least one location between the first face surface and the second face surface and a second diameter greater than the first diameter where the gas distribution holes exit the shank.

3. 3. The device of claim 2, wherein the first diameter is between 0.005 inches (0.127 mm) and 0.03 inches (0.762 mm).

4. 4. The device of claim 3, wherein the second diameter is between 0.02 inches (0.508 mm) and 0.14 inches (3.556 mm).

5. 5. The device of claim 4, wherein the first sub-portion of the shank is threaded with 10-32 threads.

6. 6. The device of claim 5, wherein a second sub-portion of the shank located between the first sub-portion of the shank and the second face surface has a diameter of 0.15 inches (3.81 mm) or less.

7. 6. The device of claim 5, wherein the transition between the shaft and the head has a radius of 0.05 inches (1.27 mm) or less.

8. 8. The apparatus of claim 7, wherein the distance between the first face surface and the second face surface is between 0.03 inches (0.762 mm) and 0.2 inches (5.08 mm).

9. 9. The device of claim 8, wherein the shank extends from the second face surface by 0.2 inches (5.08 mm) to 0.3 inches (7.62 mm).

10. 10. The device according to claim 1, wherein the head further comprises at least two side surfaces disposed between the first face surface and the second face surface.

11. 11. The device of claim 10, wherein the periphery of the first face surface and the second face surface is generally hexagonal in shape and has at least six sides, each side extending between straight sides of the periphery of the first face surface and the second face surface.

12. 12. The apparatus of claim 11, wherein the second face surface meets the six side surfaces at chamfered edges.

13. 13. The device of claim 12, wherein the first face surface meets the six side surfaces at rounded edges.

14. 12. The device of claim 11, further comprising six curved sides, each curved side sandwiched between two of the six sides, each curved side being concentric and of the same radius as the other curved sides.

15. 10. The device of any one of claims 1 to 9, wherein the head and stem are formed from an aluminum alloy or ceramic.

16. 16. The device of claim 15, wherein the head and the shank are formed from 6061-T6 aluminum alloy.

17. 10. The apparatus of claim 1, wherein the first face of the head includes two spanner drive holes extending into the head and positioned such that the gas distribution hole is located between the two spanner drive holes.

18. 18. The apparatus of claim 17, wherein the wrench drive holes are larger than the gas distribution holes and do not intersect with the gas distribution holes.

19. 10. The device of claim 1, wherein the first face surface of the head includes a hexagonal recess extending into the head.

20. 20. The apparatus of claim 19, wherein the hexagonal recess is centered about the gas distribution hole, and one end of the gas distribution hole terminates at a base of the hexagonal recess.

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