Substrate lift pins and substrate supports and processing chambers incorporating the same

Abstract

Embodiments of substrate lift pins for use in a processing chamber are provided herein. In some embodiments, a substrate lift pin includes an elongated tube having a top end and a bottom end, a magnetic insert disposed in the elongated tube proximate the bottom end, and a potting material disposed within the elongated tube and securing the magnetic insert within the elongated tube. A cap having a support surface configured to support a substrate can be disposed on the top end of the elongated tube. A rod can be disposed within the elongated tube above the magnetic insert.

Description

Technical Field

[0001] The embodiments of this disclosure generally relate to substrate processing equipment, and more particularly to a lifting rod for manipulating a substrate within a substrate processing chamber. Background Technology

[0002] In the processing of substrates such as semiconductor substrates or wafers, the substrate is typically held on a support surface of a substrate support within a processing chamber during processing. The processing chamber may include substrate lifting rods that pass through the substrate support to selectively raise or lower the substrate from or onto the support surface. In some substrate supports, the substrate lifting rod passes entirely through the substrate support and is at least partially moved (e.g., raised and lowered) relative to the substrate support surface by contacting the bottom surface of the substrate lifting rod with a structural member disposed below the substrate lifting rod. The inventors have observed that certain substrate lifting rod designs tend to fail prematurely—believed to be due to problems in manufacturing the structural members used to raise and lower the substrate lifting rod—leading to production stoppages and increased parts replacement costs.

[0003] Therefore, the inventors hereby provide an improved embodiment of a substrate lifting rod and substrate support, as well as a processing chamber comprising the same. Summary of the Invention

[0004] This document provides embodiments of a substrate lifting rod used in a processing chamber. In some embodiments, a substrate lifting rod includes: an elongated tube having a top end and a bottom end; a magnetic insert disposed within the elongated tube near the bottom end; and a potting material disposed within the elongated tube and securing the magnetic insert within the elongated tube. A cap having a support surface configured to support a substrate may be disposed at the top end of the elongated tube. A rod may be disposed within the elongated tube, above the magnetic insert. Any one or more of the elongated tube, cap, and / or rod may be made of a ceramic material, such as alumina. The potting material may be a ceramic-based potting material.

[0005] In some embodiments, a substrate support includes: a support plate having an upper surface and a plurality of through holes extending through the support plate; and a plurality of substrate lifting rods, each substrate lifting rod movably disposed in a corresponding through hole of the plurality of through holes. Each substrate lifting rod may include: an elongated tube having a top end and a bottom end; a magnetic insert disposed in the elongated tube near the bottom end; and a potting material disposed within the elongated tube and securing the magnetic insert within the elongated tube. Each substrate lifting rod may be further configured according to any embodiment disclosed herein.

[0006] In some embodiments, a processing chamber includes: a chamber body defining an internal space therein; a substrate support disposed in the internal space, the substrate support including a support plate having an upper surface and a plurality of through holes extending through the support plate; and a plurality of substrate lifting rods, each substrate lifting rod movably disposed in a corresponding through hole among the plurality of through holes. Each substrate lifting rod may include: an elongated tube having a top end and a bottom end; a magnetic insert disposed in the elongated tube near the bottom end; and a potting material disposed within the elongated tube and securing the magnetic insert within the elongated tube. Each substrate lifting rod may be further configured according to any embodiment disclosed herein.

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

[0008] The embodiments of this disclosure, which have been briefly summarized above and discussed in more detail below, can be understood by referring to the illustrative embodiments shown in the accompanying drawings. However, the drawings only illustrate typical embodiments of this disclosure and should not be considered as limiting, as other embodiments with equivalent effects are permissible.

[0009] Figure 1 A schematic side view of a substrate lifting rod is depicted according to at least some embodiments of this disclosure.

[0010] Figure 2 A schematic side view of a substrate lifting rod is depicted according to at least some embodiments of this disclosure.

[0011] Figure 3 According to at least some embodiments of this disclosure, a schematic cross-sectional side view of a processing chamber having a substrate support and a substrate lifting rod is depicted.

[0012] For ease of understanding, the same reference numerals are used as much as possible to represent the same elements in the figures. These figures are not drawn to scale and may be simplified for clarity. Elements and features of one embodiment may be advantageously incorporated into other embodiments without further explanation. Detailed Implementation

[0013] This document provides embodiments of a substrate lifting rod, a substrate support including such a lifting rod, and a processing chamber. Compared to conventional lifting rods, the substrate lifting rod provided herein generally has fewer defects, a longer service life, and a lower cost.

[0014] Figure 1A schematic side view of a substrate lifting rod 100 is depicted according to at least some embodiments of this disclosure. The substrate lifting rod 100 includes an elongated tube 102 having a top end and a bottom end. In some embodiments, the elongated tube 102 may be formed of a ceramic material, such as alumina (e.g., Al2O3). In some embodiments, the elongated tube 102 may be an extruded tube, such as an extruded ceramic material that has been extruded and fired. The inventors have found that when a solid material is drilled to form a tube, the center of the drill hole may be off-center (e.g., the hole may be axially offset and / or skewed relative to a central axis), resulting in uneven stress on the tube wall during further manufacturing and production use, which may lead to lifting rod breakage. Furthermore, the inventors have observed that the drilling process may cause cracks in the tube sidewall material, leading to lifting rod breakage. The inventors have observed that forming the elongated tube 102 into an extruded tube is advantageous in providing at least one of a more centrally located central opening and / or fewer or no cracks in the sidewalls.

[0015] A magnetic insert 104 is disposed within an elongated tube, near the bottom end of the elongated tube 102. The magnetic insert 104 can be made of any processing-compatible magnetic material, such as Invar. ® It is made of materials such as nickel-plated steel and martensitic stainless steel. During operation, the magnetic insert 104 operates to temporarily couple the substrate lifting rod 100 to the substrate lifting rod position control element, for example, as described below... Figure 3 The second lifting mechanism 326 is described.

[0016] The magnetic insert 104 is typically a cylinder or rod, but other cross-sectional shapes are also possible, with a diameter or cross-sectional dimension smaller than the inner diameter of the elongated tube 102 (e.g., a small gap, such as about 0.05-0.5 mm, or about 0.1 mm, is left between the magnetic insert 104 and the inner sidewall of the elongated tube 102). Providing a gap between the magnetic insert 104 and the elongated tube 102 facilitates the insertion of the magnetic insert 104 into the elongated tube 102 while reducing the risk of breakage of the elongated tube 102. Furthermore, the gap between the magnetic insert 104 and the elongated tube 102 advantageously facilitates the retention of the magnetic insert 104 within the elongated tube 102 when the gap is filled with potting material, as discussed below.

[0017] The magnetic insert 104 can typically be of any length not exceeding the length of the elongated tube 102. In some embodiments, the length of the magnetic insert 104 is not greater than half the length of the elongated tube 102, or in some embodiments, not greater than one-quarter the length of the elongated tube 102. Providing a shorter magnetic insert 104 advantageously reduces the cost of the substrate lifting rod 100 and further prevents any undesired interaction with the processing performed on the substrate.

[0018] A potting material 106 is disposed within an elongated tube 102 and secures the magnetic insert 104 within the elongated tube 102 (e.g., by filling the gap between the magnetic insert 104 and the elongated tube 102, securing it from above and / or from the side). The inventors have observed that merely pressing the magnetic insert into the elongated tube can sometimes cause the magnetic insert to partially or completely slip out of the elongated tube. The potting material 106 advantageously enhances the retention force of the magnetic insert 104 within the elongated tube 102. In some embodiments, the potting material 106 substantially fills the entire interior area of ​​the elongated tube 102, except for the space occupied by the magnetic insert 104. The magnetic insert 104 can be completely embedded within the elongated tube 102 by the potting material 106, or the bottom surface of the magnetic insert 104 can be exposed at the bottom of the elongated tube 102.

[0019] The potting material can be any processing-compatible potting material, which acts as both a filler and a binder to bond the magnetic insert 104 to the elongated tube 102. In some embodiments, the potting material 106 can be a ceramic potting material, such as an alumina-based potting material, a zirconia-based potting material, etc. Examples of suitable potting materials include Durapot, available from Cotronics Corp. in Brooklyn, New York. ™ 801 and RESBOND ™ 908.

[0020] In some implementations, and such as Figure 2 The substrate lifting rod 200, which is otherwise identical to the substrate lifting rod 100, may include a rod 202 disposed within the elongated tube 102 above the magnetic insert 104. The rod 202 is typically cylindrical, but other cross-sectional shapes are possible. The diameter or cross-sectional dimension of the rod 202 is smaller than the inner diameter of the elongated tube 102 (e.g., leaving a small gap between the rod 202 and the inner sidewall of the elongated tube 102). The rod 202 may typically be any length not exceeding the length of the elongated tube 102 not occupied by the magnetic insert 104 (e.g., the length of the magnetic insert 104 and the rod 202 together may be the same as or shorter than the length of the elongated tube 102). In some embodiments, the length of the magnetic insert 104 and the rod 202 together is the same as the length of the elongated tube 102. The rod 202 may be formed from any of the materials described above for the elongated tube 102. The rod 202 is typically held within the elongated tube 102 by a potting material 106. In some embodiments, the potting material 106 substantially fills the entire interior area of ​​the elongated tube, except for the space occupied by the magnetic insert 104 and the rod 202.

[0021] Providing a rod 202 inside the elongated tube 102 helps reduce the volume of potting material 106 required to fill the interior of the elongated tube 102, thereby mitigating any potential shrinkage issues of the potting material 106. Furthermore, securing the rod 202 to the elongated tube 102 enhances the strength of the substrate lifting rod 100 and reduces or prevents the propagation of any cracks that may occur in the elongated tube 102, thus increasing the service life of the substrate lifting rod 100.

[0022] A cover 108 having a support surface configured to support a substrate may be disposed on the top end of the elongated tube 102. The cover 108 typically includes a first surface opposite the elongated tube 102 and is configured to support the substrate during use. In some embodiments, the cover 108 is bonded to the elongated tube 102. The cover 108 may be formed of any material described above with respect to the elongated tube 102.

[0023] Figure 3 According to at least some embodiments of this disclosure, a schematic cross-sectional side view of a processing chamber having a substrate support and a substrate lifting rod is depicted. The processing chamber 300 can be configured to perform processing on a substrate (e.g., a semiconductor wafer). Suitable processes include etching, deposition, treatment, metering, etc. In some embodiments, the processing chamber 300 is typically a vacuum chamber, suitable for maintaining subatmospheric pressure within the internal space 320 during substrate processing. The processing chamber 300 includes a chamber body 302 having a base plate 304, a cover 306, and sidewalls 308 extending from the base plate 304 to the cover 306. The chamber body 302 is made of a suitable material, such as aluminum. The processing chamber 300 may also include one or more sheaths surrounding various chamber components to prevent undesirable reactions between these components and the ionized processing material. The chamber body 302 can be grounded via a grounding coupler.

[0024] In some embodiments, the nozzle 322 is disposed within the internal volume 320, near the cover 306 and opposite to the substrate support 310 for supporting the substrate 312. The nozzle 322 is coupled to and in fluid communication with a process gas supplier 324, which allows one or more process gases to be supplied into the internal volume 320 for processing the substrate 312. The internal volume 320 may include a processing space located in the upper half of the internal volume 320 and generally between the substrate support 310 and the nozzle 322.

[0025] A substrate support 310 is disposed within an internal volume 320 to support and hold a substrate 312, such as a semiconductor wafer, or other substrate that can be held. The substrate support 310 may typically include a base 314 coupled to a hollow shaft 316. The substrate support 310 may be configured in various ways to support and hold the substrate 312, for example, by including an electrostatic chuck. Other components, such as edge rings, may be provided on the substrate support 310.

[0026] Hollow shaft 316 provides conduits for supplying base 314 with, for example, backside gas, process gas, fluid, coolant, electricity, etc. In some embodiments, hollow shaft 316 is coupled to lifting mechanism 318, such as an actuator or motor, which provides vertical movement of base 314 between an upper processing position and a lower conveying position. Bellows assembly 338 is disposed around hollow shaft 316 and coupled between base 314 and the bottom surface of processing chamber 300 to provide a resilient seal that allows vertical movement of base 314 while preventing vacuum loss within processing chamber 300.

[0027] In some embodiments, the hollow shaft 316 facilitates coupling of a back-side gas supply, a clamping power supply, and an RF power supply (e.g., an RF plasma power supply and a bias power supply) to the base 314. The back-side gas supply 141 is disposed outside the chamber body 302 and supplies heat transfer gas to the base 314. In some embodiments, the RF plasma power supply 170 and the bias power supply 117 are coupled to the base 314 via corresponding RF matching networks. In some embodiments, the substrate support 310 may alternatively include an AC, DC, or RF bias power supply. In some embodiments, the AC, DC, or RF bias power supply may be pulsed.

[0028] Multiple substrate lifting rods 328 (e.g., substrate lifting rods 100 or 200 described above) are provided to lower or raise the substrate 312 onto or remove it from the base 314 as needed. The multiple substrate lifting rods 328 extend through the substrate support 310. A platform 330 is connected to a shaft 332 coupled to a second lifting mechanism 326 for raising and lowering the platform 330 and by contacting the multiple substrate lifting rods 328. The platform 330 may include multiple magnets whose positions correspond to the positions of the multiple substrate lifting rods 328. The magnets attract the substrate lifting rods 328 (e.g., via the magnetic insert 104 described above) to facilitate uniform positioning of the multiple substrate lifting rods 328 by controlling the position of the platform 330 via the second lifting mechanism 326. A bellows assembly 334 is coupled between the second lifting mechanism 326 and the base plate 304 to provide a resilient seal, thereby maintaining a chamber vacuum during vertical movement provided by the second lifting mechanism 326. In some embodiments, such as Figure 3 As shown, the second lifting mechanism 326 is located on the outside of the hollow shaft 316.

[0029] Processing chamber 300 is coupled to and in fluid communication with a vacuum system (e.g., including a throttle valve and a vacuum pump, not shown) for venting processing chamber 300. The pressure inside processing chamber 300 can be adjusted by regulating the throttle valve and / or the vacuum pump. Processing chamber 300 includes a slit valve 336 having a substrate transfer opening that can be selectively opened or closed to facilitate the transfer of substrate 312 in and out of internal volume 320. In some embodiments, a transfer robot (not shown) having one or more transfer blades is configured to transfer substrate 312.

[0030] Although the foregoing describes the implementation of this disclosure, other and further implementations of this disclosure can be designed without departing from the basic scope of this disclosure.

Claims

1. A substrate lifting rod, the substrate lifting rod comprising: A long, narrow tube having a top end and a bottom end; A magnetic insert, the magnetic insert being disposed within the elongated tube near the bottom end; and A potting material is disposed inside the elongated tube and the magnetic insert is secured inside the elongated tube.

2. The substrate lifting rod of claim 1, further comprising a cover disposed at the top end of the elongated tube, wherein the cover includes a support surface configured to support a substrate thereon.

3. The substrate lifting rod as claimed in claim 1, wherein the substrate lifting rod further comprises a rod disposed within the elongated tube and located above the magnetic insert.

4. The substrate lifting rod as claimed in claim 3, wherein the rod is made of ceramic material.

5. The substrate lifting rod as claimed in any one of claims 1 to 4, wherein it is at least one of the following: The elongated tube is made of ceramic material; or The potting material is a ceramic-based potting material.

6. The substrate lifting rod according to any one of claims 1 to 4, wherein the elongated tube is made of aluminum oxide.

7. The substrate lifting rod according to any one of claims 1 to 4, wherein the elongated tube is an extruded tube.

8. The substrate lifting rod of claim 1, further comprising a cover disposed on the top end of the elongated tube, wherein the cover includes a support surface configured to support a substrate thereon, wherein both the elongated tube and the cover are made of a ceramic material, and wherein the potting material is a ceramic-based potting material.

9. The substrate lifting rod of claim 8, wherein the substrate lifting rod further comprises a rod disposed within the elongated tube and above the magnetic insert.

10. A substrate support member, the substrate support member comprising: A support plate having an upper surface and a plurality of through holes extending through the support plate; and A plurality of substrate lifting rods, each substrate lifting rod being movably disposed in a corresponding through hole of the plurality of through holes, wherein at least one substrate lifting rod is as described in claim 1.

11. The substrate support of claim 10, wherein the substrate support further comprises at least one of the following: A cap, disposed on the top end of the elongated tube, wherein the cap includes a support surface configured to support a substrate thereon; or A rod, which is disposed inside the elongated tube and located above the magnetic insert.

12. The substrate support as claimed in claim 10, wherein at least one of the following is included: The slender tube is made of ceramic material; or The potting material is a ceramic-based potting material.

13. The substrate support of claim 10, further comprising a cap disposed on the top end of the elongated tube, wherein the cap includes a support surface configured to support a substrate thereon, wherein both the elongated tube and the cap are made of a ceramic material, and wherein the potting material is a ceramic-based potting material.

14. The substrate support of claim 13, further comprising a rod disposed within the elongated tube above the magnetic insert.

15. A processing chamber, the processing chamber comprising: A chamber body, within which an internal volume is defined; A substrate support member disposed within the internal volume, the substrate support member being as described in any one of claims 10 to 14.

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