Improved thread profile for semiconductor processing chamber components

Abstract

Embodiments of components for use in a substrate processing chamber are provided herein. In some embodiments, a component for use in a substrate processing chamber includes a body having an opening extending partially through the body from a top surface of the body, wherein the opening includes a threaded portion for fastening the body to a second processing chamber component, wherein the threaded portion includes a plurality of threads defining a plurality of circular peaks and a plurality of circular roots, and wherein a depth of the threaded portion is a radial distance between a circular peak of the plurality of circular peaks and an adjacent root of the plurality of circular roots, the depth of the threaded portion decreasing from a first depth to a second depth at a last thread of the plurality of threads.

Description

Technical Field

[0001] The embodiments disclosed herein are generally related to substrate processing equipment. Background Technology

[0002] Fasteners are widely used to couple two components together in substrate processing equipment. Fasteners typically have external threads on their outer surface that mate with the internal threads of any component to be coupled. However, some components with conventional internal thread profiles may break when conventional fasteners engage with internal threads.

[0003] Therefore, the inventors provide embodiments of components with improved thread profiles to facilitate fastening with other components. Summary of the Invention

[0004] This document provides embodiments of a component for use in a substrate processing chamber. In some embodiments, a component for use in a substrate processing chamber includes: a body having an opening extending partially through the body from a top surface of the body, wherein the opening includes a threaded portion for fastening the body to a second processing chamber component, wherein the threaded portion includes a plurality of threads defining a plurality of circular peaks and a plurality of circular roots, and wherein the depth of the threaded portion is the radial distance between a circular peak among the plurality of circular peaks and an adjacent root among the plurality of circular roots, the depth of the threaded portion decreasing from a first depth to a second depth at the last thread among the plurality of threads.

[0005] In some embodiments, an electrode for a substrate processing chamber includes: a body made of a silicon-based material having an opening extending partially through the body from a top surface of the body, wherein the opening includes a threaded portion having a plurality of threads in a helical pattern and having an internal thread clearance, the plurality of threads defining a plurality of circular peaks and a plurality of circular roots, the internal thread clearance being disposed between the threaded portion and a lower surface of the opening, and wherein the depth of the threaded portion is the radial distance between a circular peak among the plurality of circular peaks and an adjacent root among the plurality of circular roots, the depth of the threaded portion decreasing from a first depth to a substantially zero depth along the last thread among the plurality of threads.

[0006] In some embodiments, a nozzle assembly for use in a substrate processing chamber includes: a gas distribution plate; an electrode having an opening partially extending through the electrode, wherein the opening includes a threaded portion having a plurality of threads in a helical pattern, the plurality of threads defining a plurality of circular peaks and a plurality of circular roots, and wherein the depth of the threaded portion is a radial distance between a circular peak among the plurality of circular peaks and an adjacent root among the plurality of circular roots, the depth of the threaded portion decreasing from a first depth to a second depth along the last thread among the plurality of threads; and a fastener disposed through the gas distribution plate and disposed in the opening to secure the electrode to the gas distribution plate.

[0007] Other and further embodiments of this disclosure are described below. Attached Figure Description

[0008] The embodiments of this disclosure have been briefly summarized above and are discussed in more detail below, which can be understood by referring to the exemplary embodiments of this disclosure depicted in the accompanying drawings. However, the accompanying drawings depict only typical embodiments of this disclosure, and since this disclosure allows for other equivalent embodiments, the accompanying drawings should not be considered as limiting the scope.

[0009] Figure 1 A processing chamber is depicted according to some embodiments of the present disclosure.

[0010] Figure 2 A cross-sectional side view of a component according to some embodiments of the present disclosure is depicted.

[0011] Figure 3 A side view depicting a threaded insert according to some embodiments of the present disclosure.

[0012] Figure 4 A top equidistant cross-sectional view depicting a plurality of components fastened together according to some embodiments of the present disclosure.

[0013] For ease of understanding, the same reference numerals are used to represent the same components in the figures where possible. For clarity, the figures are not drawn to scale and may be simplified. Components and features in one embodiment may be advantageously incorporated into other embodiments without further description. Detailed Implementation

[0014] This document provides embodiments of components used in a substrate processing chamber. The component can be any suitable part of the substrate processing chamber coupled to another component. In some embodiments, the component is part of a nozzle assembly, chamber liner, etc. The component typically includes one or more openings with internal threads for coupling to another component via one or more fasteners. The inventors have observed that internal threads with sharp features can cause component breakage. The internal threads of the components disclosed herein include rounded features to advantageously reduce or prevent component breakage when one or more fasteners are torqued through the internal threads.

[0015] Figure 1 A processing chamber 100 according to some embodiments of the present disclosure is depicted. In some embodiments, the processing chamber 100 is an etching processing chamber. However, other types of processing chambers configured for different processes may also be used with embodiments of the components described herein or modified for use with embodiments of the components described herein.

[0016] Processing chamber 100 is a vacuum chamber suitably adapted to maintain sub-atmospheric pressure within internal space 120 during substrate processing. Processing chamber 100 includes a chamber body 106 having sidewalls and a bottom wall. Chamber body 106 is covered by a cover 104, and chamber body 106 and cover 104 together define an internal volume 120. Chamber body 106 and cover 104 may be made of a metal (such as aluminum). Chamber body 106 may be grounded via coupling to ground 115.

[0017] A substrate support 124 is disposed within an internal space 120 to support and hold a substrate 122 (such as a semiconductor wafer) or other electrostatically holdable substrates. The substrate support 124 typically includes a base 128 and a hollow support shaft 112 for supporting the base 128. The base 128 may include an electrostatic chuck (not shown). The hollow support shaft 112 provides conduits to supply the base 128 with, for example, backside gas, process gas, fluid, coolant, power, etc.

[0018] The substrate support 124 is coupled to an RF source (e.g., an RF bias power supply 117 or an RF plasma power supply 170). In some embodiments, the RF bias power supply 117 is coupled to the base 128 via one or more RF matching networks (not shown). In some embodiments, the substrate support 124 may alternatively include AC or DC bias power.

[0019] The processing chamber 100 is also coupled to and in fluid communication with a gas supply 118, which supplies one or more processing gases to the processing chamber 100 for processing the substrate 122 disposed therein. A nozzle assembly 132 is disposed in an internal volume 120 opposite to a substrate support 124. In some embodiments, the nozzle assembly 132 is coupled to a cover 104. The nozzle assembly 132 and the substrate support 124 partially define a processing volume 144 therebetween. The nozzle assembly 132 includes a plurality of openings 110 for dispensing one or more processing gases from the gas supply 118 into the processing volume 144.

[0020] Nozzle assembly 132 typically includes a gas distribution plate 142 coupled to electrode 136. In some embodiments, a plurality of openings 110 extend through gas distribution plate 142 and electrode 136. In some embodiments, electrode 136 is disposed in an internal volume 120 opposite to substrate support 124. Electrode 136 is coupled to one or more power sources (e.g., RF plasma power source 170) to ignite one or more process gases. In some embodiments, electrode 136 comprises a silicon-based material, such as monocrystalline silicon, polycrystalline silicon, silicon carbide, etc., or a material substantially composed of monocrystalline silicon, polycrystalline silicon, silicon carbide, etc.

[0021] In some embodiments, a liner 146 is disposed within the interior space 120 around at least one of the substrate support 124 and the nozzle assembly 132 to confine plasma therein. The liner 146 also protects the sidewalls of the chamber body 106 from unwanted deposition. The liner 146 includes an opening 155 corresponding to a slit valve 160 of the chamber body 106 for moving the substrate 122 into the processing chamber in a first direction 172 and out of the processing chamber 100 in a second direction 174. In some embodiments, the liner 146 includes an upper portion coupled to a lower portion. The processing chamber 100 is coupled to and in fluid communication with a vacuum system 114, which includes a throttle valve and a vacuum pump for venting the processing chamber 100. The pressure inside the processing chamber 100 can be regulated by adjusting the throttle valve and / or the vacuum pump.

[0022] In operation, for example, plasma may be generated in processing volume 144 to perform one or more processes. Power from a plasma power source (such as RF plasma power source 170) may be coupled to the processing gas via one or more electrodes (e.g., electrode 136) near or within internal volume 120 to ignite the processing gas and generate plasma. Bias power may also be supplied from a bias power source (e.g., RF bias power supply 117) to one or more electrodes 154 within electrostatic chuck 150 to attract ions from the plasma to substrate 122.

[0023] Figure 2 A cross-sectional side view of a component 200 according to some embodiments of the present disclosure is depicted. In some embodiments, the component 200 is located in a substrate processing chamber (e.g., Figure 1 Any suitable component used in the processing chamber 100. For example, component 200 could be electrode 136, gas distribution plate 142, gasket 146, etc.

[0024] Component 200 includes a body 202 having an opening 206 extending partially through the body 202 from its top surface 204. The opening 206 includes a threaded portion 212 for fastening the body 202 to a second processing chamber component. Figure 4 (As shown in the diagram). For example, if the component is electrode 136, the second processing chamber component may be a gas distribution plate 142. The threaded portion 212 includes a plurality of threads 214 in a helical pattern. The plurality of threads 214 have a plurality of rounded crests 220 and a plurality of rounded roots 224. In some embodiments, the plurality of rounded crests have a radius of about 0.01 to about 0.025 inches. Therefore, compared to conventional threads, the plurality of threads 214 have reduced edges or no sharp edges.

[0025] The plurality of threads 214 may include a last thread 214A, an initial thread 214B, and a center thread 214C. In some embodiments, the last thread 214A includes the last span of the plurality of threads 214 extending approximately 360 degrees relative to the central axis of the opening 206. In some embodiments, the initial thread 214B includes the initial span of the plurality of threads 214 extending approximately 360 degrees relative to the central axis of the opening 206. The center thread 214C extends continuously from the initial thread 214B to the last thread 214A. In some embodiments, the major diameter of the center thread 214C is approximately 0.25 inches to approximately 0.50 inches. In some embodiments, the minor diameter of the center thread 214C is approximately 0.20 inches to approximately 0.40 inches.

[0026] The depth of the threaded portion is the radial distance between adjacent circular peaks in the plurality of circular peaks 220 and adjacent roots in the plurality of circular roots 224. The depth of the center thread 214C is a first depth D. In some embodiments, the first depth D is substantially constant along the path of the center thread 214C. In some embodiments, the first depth is about 0.01 inches to about 0.04 inches. The depth of the final thread 214A is a second depth. In some embodiments, the second depth decreases along the path of the final thread 214A to provide a smoother transition between the plurality of threads 214 and the sidewalls of the opening 206. In some embodiments, the second depth decreases along the path of the final thread 214A from the first depth D to a substantially zero depth D'. The depth of the initial thread 214B is a third depth. In some embodiments, the third depth increases along the path of the initial thread 214B to the first depth. In some embodiments, the third depth increases from a substantially zero depth D' to the first depth D to provide a smooth transition from the sidewalls of the opening 206 and the plurality of threads 214.

[0027] The pitch of the threaded portion 212 is the axial distance between equivalent points on adjacent threads of the plurality of threads 214. In some embodiments, the center pitch P of the center thread 214C is about 0.04 inches to about 0.070 inches. In some embodiments, the plurality of threads 214 have a pitch angle of about 45 degrees to about 75 degrees.

[0028] In some embodiments, opening 206 includes an internal thread relief 208 disposed between the final thread 214A and the lower surface 210 of opening 206. In some embodiments, the internal thread relief 208 has a substantially constant diameter. In some embodiments, the diameter of the internal thread relief 208 is the same as the minor diameter of the center thread 214C. In some embodiments, the length 240 of the internal thread relief 208 is about 5% to about 25% of the length 230 of opening 206. In some embodiments, opening 206 includes a countersink 218 adjacent to the top surface 204 of body 202. In some embodiments, body 202 is made of a silicon-based material (e.g., monocrystalline silicon, polycrystalline silicon, silicon carbide, etc., or a material substantially composed of monocrystalline silicon, polycrystalline silicon, silicon carbide, etc.).

[0029] Figure 3A side view of a threaded insert 300 according to some embodiments of the present disclosure is depicted. In some embodiments, the threaded insert 300 may be disposed in an opening 206 to reduce stress on the body 202 of the component 200 when a fastener is twisted therein. The threaded insert 300 has a circular threaded portion 302 formed on its outer surface 304, corresponding to the threaded portion 212 of the body 202. The circular threaded portion 302 defines a plurality of circular peaks 320 and a plurality of circular roots 324. In some embodiments, the plurality of circular peaks have a radius of about 0.007 to about 0.02 inches. In some embodiments, the circular threaded portion 302 has the same pitch angle as the center thread 214C of the component 200.

[0030] The threaded insert 300 may be made of any suitable material. For example, the threaded insert 300 may be made of plastic. In some embodiments, the lower portion 310 of the threaded insert includes an internal thread relief 314. In some embodiments, the length of the internal thread relief 314 is similar to the length 240 of the internal thread relief 208 of the opening 206. In some embodiments, the threaded insert 300 includes a chamfered upper edge 318.

[0031] Figure 4 Top equidistant cross-sectional views depicting a plurality of components fastened together according to some embodiments of the present disclosure. In some embodiments, component 200 is coupled to a second component 402, such as... Figure 4 As shown. Fastener 408 may extend through the second component 402 and into the opening 206 to couple the second component 402 to component 200.

[0032] In some embodiments, the circular threaded portion 302 of the threaded insert 300 engages with the threaded portion 212 of the body 202. In some embodiments, the upper surface of the threaded insert 300 includes one or more tool openings 404 for facilitating a tool to twist the threaded insert 300 into an opening 206. In some embodiments, the one or more tool openings 404 include two diametrically opposed openings. When twisted or tightened, the threaded insert 300 advantageously protects the component 200 from breakage by absorbing stress from the fastener 408. If the fastener 408 is overtightened, the threaded insert 300 may break, while the protected component 200 is protected from breakage.

[0033] In some embodiments, the threaded insert 300 includes a central opening 406 having an internal thread 412. In some embodiments, the internal thread 412 engages with the external thread 418 of the fastener 408 to couple the second component 402 to the component 200. In some embodiments, a helical metal insert 414 is retained within the central opening 406 of the threaded insert 300. The helical metal insert 414 includes an internal thread 416 that engages with the external thread 418 of the fastener 408. The helical metal insert 414 may advantageously provide a more robust engagement interface for the fastener 408 than the internal thread 412 of the threaded insert 300.

[0034] While the foregoing describes embodiments of this disclosure, other and further embodiments of this disclosure may be designed without departing from the basic scope of this disclosure.

Claims

1. A component for use in a substrate processing chamber, comprising: A body having an opening extending partially through the body from its top surface, wherein the opening includes a threaded portion for fastening the body to a second processing chamber component, wherein the threaded portion includes a plurality of threads defining a plurality of circular peaks and a plurality of circular roots, and wherein the depth of the threaded portion is the radial distance between a circular peak among the plurality of circular peaks and an adjacent root among the plurality of circular roots, the depth of the threaded portion decreasing from a first depth to a second depth at the last thread among the plurality of threads; The opening includes an internal thread relief disposed between the last thread of the threaded portion and the lower surface of the opening, and the internal thread relief has a substantially constant diameter.

2. The component of claim 1, wherein the body is made of a silicon-based material.

3. The component of claim 1, wherein the second depth decreases from the first depth to a substantially zero depth along the last thread of the plurality of threads.

4. The component of claim 1, wherein the depth of the threaded portion increases from substantially zero to the first depth along the path of the initial thread of the plurality of threads.

5. The component of claim 1, wherein the length of the internal thread cut is 5% to 25% of the length of the opening.

6. The component of claim 1, wherein the plurality of threads have a pitch angle of 45 to 75 degrees.

7. The component of claim 1, wherein the first depth is 0.01 inches to 0.04 inches.

8. The component of any one of claims 1 to 7, wherein the component is an electrode for a substrate processing chamber, and wherein the plurality of threads are helical threads.

9. The component as claimed in any one of claims 1 to 7, wherein the threaded portion has a large diameter of 0.25 inches to 0.50 inches.

10. The component as claimed in any one of claims 1 to 7, wherein the depth of the threaded portion increases from substantially zero to the first depth along the path of the initial thread of the plurality of threads.

11. The component as claimed in any one of claims 1 to 7, wherein the component is coupled to the second component via a fastener.

12. A component for use in a substrate processing chamber, comprising: A body having an opening extending partially through the body from its top surface, wherein the opening includes a threaded portion for fastening the body to a second processing chamber component, wherein the threaded portion includes a plurality of threads defining a plurality of circular peaks and a plurality of circular roots, and wherein the depth of the threaded portion is the radial distance between a circular peak among the plurality of circular peaks and an adjacent root among the plurality of circular roots, the depth of the threaded portion decreasing from a first depth to a second depth at the last thread among the plurality of threads; as well as A threaded insert, wherein the threaded insert is disposed in the opening and has a circular threaded portion formed on the outer surface of the threaded insert corresponding to the threaded portion of the body, wherein the circular threaded portion engages with the threaded portion of the body, and wherein the lower portion of the threaded insert includes an internal thread relief.

13. The component of claim 12, wherein the threaded insert is made of plastic.

14. A nozzle assembly for use in a processing chamber, comprising: Gas distribution plate; A component comprising a body having an opening extending partially through the body from a top surface of the body, wherein the opening includes a threaded portion for fastening the body to a second processing chamber component, wherein the threaded portion includes a plurality of threads defining a plurality of circular peaks and a plurality of circular roots, and wherein the depth of the threaded portion is the radial distance between a circular peak among the plurality of circular peaks and an adjacent root among the plurality of circular roots, the depth of the threaded portion decreasing from a first depth to a second depth at the last thread among the plurality of threads, wherein the component is an electrode for a substrate processing chamber; as well as Fasteners, the fasteners being disposed through the gas distribution plate and in the opening, for securing the electrode to the gas distribution plate, wherein at least one of the following is satisfied: The opening includes an internal thread relief, which is disposed between the last thread of the threaded portion and the lower surface of the opening, and wherein the internal thread relief has a substantially constant diameter, or The device further includes a threaded insert disposed in the opening and having a circular threaded portion formed on the outer surface of the threaded insert corresponding to the threaded portion of the electrode, wherein the circular threaded portion engages with the threaded portion of the electrode, and wherein the lower portion of the threaded insert includes an internal thread notch, or The length of the internal thread cut is 5% to 25% of the length of the opening.

15. The nozzle assembly of claim 14, further comprising the threaded insert disposed in the opening and wherein the threaded insert includes a central opening that engages with the fastener.

16. The nozzle assembly of claim 15, further comprising a helical metal insert held within the central opening of the threaded insert, wherein the helical metal insert includes an internal thread that engages with the external thread of the fastener.

17. The nozzle assembly of claim 15, wherein the threaded insert is made of plastic.

18. The nozzle assembly of claim 17, wherein the electrode is made of a silicon-based material.

Images