JP5361119B2 - Reduction of electrostatic charge by roughening the susceptor - Google Patents

Abstract

A substrate support and method for fabricating the same are provided. In one embodiment of the invention, a substrate support includes an electrically conductive body having a substrate support surface that is covered by an electrically insulative coating. At least a portion of the coating centered on the substrate support surface has a surface finish of between about 200 to about 2000 micro-inches. In another embodiment, a substrate support includes an anodized aluminum body having a surface finish on the portion of the body adapted to support a substrate thereon of between about 200 to about 2000 micro-inches. In one embodiment, a substrate support assembly includes an electrically conductive body having a substrate support surface, a substrate support structure that is adapted to support the conductive body and the conductive body is covered by an electrically insulative coating.

Description

Disclosure background

Field of Invention
[0001] Embodiments of the present invention generally provide a substrate support for use in semiconductor processing and a method for manufacturing the same.

Background art description

  [0002] Liquid crystal displays and flat panels are commonly used in active matrix displays such as computers, television monitors, personal digital assistants (PDAs) and mobile phones. In general, a flat panel includes two glass plates that sandwich a single layer of liquid crystal material. At least one of the glass plates is coupled to a power source and includes at least one conductive film disposed thereon. The power supplied from the power source to the conductive film changes the orientation of the crystal material, creating patterns such as text and graphics that can be seen on the display. One manufacturing process frequently used to produce flat panels is plasma enhanced chemical vapor deposition (PECVD).

  [0003] Plasma enhanced chemical vapor deposition is commonly employed to deposit thin films on substrates such as flat panels and semiconductor wafers. Plasma chemical vapor deposition is generally accomplished by introducing a precursor gas into a vacuum chamber containing a substrate. The precursor gas is usually directed through a distribution plate placed near the top of the chamber. The chamber precursor gas is energized (eg, excited) into the plasma by applying RF power to the chamber from one or more RF sources coupled to the chamber. The excited gas reacts to form a layer of material on the surface of the substrate positioned on the temperature controlled substrate support. In applications where the substrate receives a layer of low temperature polysilicon, the substrate support may be heated above 400 degrees Celsius. Volatile by-products generated during the reaction are delivered from the chamber through an exhaust system.

  [0004] In general, large area substrates utilized in flat panel manufacturing are large, often exceeding 550 mm x 650 mm, and assuming a surface area of 4 square meters or more. Correspondingly, the substrate support used to process large area substrates is proportionally large to accommodate the large surface area of the substrate. Typically, a substrate support intended for high temperature use is cast to encapsulate one or more heating elements and thermocouples in an aluminum body. Depending on the size of the substrate support, one or more stiffening members are typically placed within the substrate support to reduce the rigidity and high operating temperature of the substrate support (ie, 350 degrees Celsius to minimize the hydrogen content of some membranes). To improve performance at over 500 degrees Celsius). The aluminum substrate support is then anodized to provide a protective coating.

  [0005] Although the substrate support configured in this manner exhibited good processing performance, small local variations in thickness were observed that could be harmful to next-generation devices formed on large area substrates This often appears as a spot with a smaller film thickness. The variation is the glass thickness and flatness associated with a smooth substrate support surface, typically about 50 microinches, by creating a local capacitance variation at a fixed location across the glass substrate, eg deposition variation, eg deposition It appears that local plasma inhomogeneities can be created that result in small film thickness spots. Substrate support aging and modified plasma conditioning have been shown to reduce thin spot formation, especially when performed in conjunction with an extended chamber vacuum purge prior to transferring the substrate to the chamber for processing. However, the resulting time and material consumption required for the method and this unfavorable impact on cost and throughput make it desirable to obtain a more effective solution.

  [0006] As the substrate size increases from about 370 mm x 470 mm to about 1200 mm x 1040 mm, or even 1800 mm x 2200 mm, other new defect modes become a significant problem in the manufacture of flat panel display devices. As next-generation substrates continue to increase in size, the importance of defect reduction becomes more and more important due to substantial investment by flat panel manufacturers on each substrate. Furthermore, with the continuous development of critical dimensional reduction of devices that require more precise tolerances for film uniformity, film thickness variation reduction and / or elimination can be achieved for next-generation devices formed on large area substrates. It is an important factor for economic generation.

  [0007] In addition, the effectiveness of the substrate manufacturing process is often measured by two related important factors: device yield and cost of ownership (CoO). These factors are important because they directly affect the cost of producing electronic devices and thus the competitiveness of device manufacturers in the market. CoO affected by a number of factors is greatly affected by the initial cost of processing hardware and the replacement cost of consumable hardware. In efforts to reduce CoO, electronic device manufacturers often spend a lot of time trying to optimize processing hardware and wear costs to achieve maximum margins without impacting particle and process yield performance. Another important factor in CoO calculation is system reliability and system availability. These factors are very important to the profitability and / or usefulness of the cluster tool because the longer the system is unable to process the substrate, the more memory is lost by the user due to the loss of opportunity to process the substrate with the cluster tool. Is important to. Therefore, cluster tool users and manufacturers spend a lot of time trying to develop reliable processes, reliable hardware and reliable systems with high availability.

  [0008] One defect that appears to be a problem with PECVD-type processes for large area substrates is a defect known in the industry as an electrostatic discharge (ESD) metal line arc problem. As the substrate size increases, the induced current induced in the longer and larger ESD metal lines during plasma deposition appears to be so large that damage from the plasma-induced arc to the substrate is a major recurrence issue. Gate metal lines in flat panel display applications connected to ESD discharge lines are typically about 5-10 micrometers (μm) wide and may be about 1 meter or 2 meters, whereas In semiconductor applications of this type, the gate metal lines are up to several tens of millimeters in length and approximately 90 nanometers in size, so this problem is generally less common in smaller semiconductor device manufacturing applications (eg, 150-300 mm circular silicon substrates). ) Does not occur. The width of the ESD line of the flat panel display substrate is usually larger than 1 mm and may be about 1 to 2 meters long. Thus, ESD metal lines in flat panel display applications are intended to act as antennas that can collect large amounts of charge during plasma processing that causes arc damage to the substrate. Accordingly, there is a greater need to reduce the possibility of arcing due to interaction with the plasma by increasing the resistance of the discharge path to ground. The thickness of a flat panel substrate that is significantly larger than a semiconductor substrate (eg, 0.7 mm) has not changed significantly from a large or small size flat panel display type substrate.

  [0009] Another defect that has arisen in processing 1200 mm × 1040 mm or larger substrates is an increase in the number of particles found on the backside of the substrate after performing a plasma process on the substrate, such as a PECVD process. The larger the glass substrate size, the greater the ability to trap electrostatic charges during plasma processing, thereby allowing particles found in the processing chamber to be attracted to the substrate surface where they are held by the trapped charge. Seem.

  [0010] The arc and electrostatic charge problems appear to be different for flat panel display applications and semiconductor applications due to the size and characteristics of different substrate materials. The electrostatic charge generated by the triboelectric process, or the process of bringing two materials into contact with each other and then separating them from each other, is affected by a number of factors, two of which are surface contacts between the two components. The quantity and the motion function of the two materials. The difference between flat panel and semiconductor applications is the difference in properties of the substrate material (s) (eg, glass versus silicon (or aluminum)) used in each of these applications, which is known as an operating function Related to material properties. In general, the operating function describes the material's ability to hold on free electrons (electrons that orbit the outermost shell of the material). In general, a material with a higher operating function (eg, silicon) is placed in contact with a given material and then separated from the material (eg, glass) with a lower operating function. ) Is less likely to give up electrons. (See the reference “Triboelectric Generation: Getting Charged” in EE-Evaluation Engineering written by Ryne C. Allen in November 2000.) Thus, the problem of electrostatic charge generation is a problem with materials that the treated substrate contacts. The charge amount and charge polarity generated by the flat panel display substrate versus the semiconductor substrate is not the same.

  [0011] The second triboelectric factor, the amount of contact between paths, is that the greater the contact between the components, the more charge that will be transferred between the contact component and possibly the arc. I mean. The amount of surface roughness of the two components directly affects the amount of contact between the two paths. Therefore, some prior art applications, such as US Pat. No. 6,063,203, filed June 2, 1998, roughened the surface of the susceptor (substrate support) to 1-8 micrometers Ra. The reference requires a final step of polishing the roughened susceptor surface that reduces roughness and increases contact between the two substrate components. Reduced roughness, ie increased contact between the two substrate components, increases trapping charge sufficient to form arcs and attract particles by increasing triboelectric charge transfer between the substrate and substrate support. Increase the possibility of generating. An alternative theory is that the step of polishing the roughened surface as described in the prior art roughens the substrate support surface, such as improved electrical contact between the two paths (ie, the susceptor surface and the glass substrate). This is a point that is considered to remove a part of the advantage received by the conversion. Improved electrical contact is created by the sharp tip of the roughened surface, which is believed to reduce charge build-up between the two paths during plasma processing, and by greater contact stress at high points, thereby increasing the substrate surface. It seems to reduce the potential for arcing and particle attraction.

  [0012] Accordingly, there is a need for an improved substrate support that solves all of these problems that arise above.

Summary of the Invention

  [0013] A substrate support and method of manufacturing the same are provided. In one embodiment of the present invention, the substrate support includes a conductive body having a substrate support surface, an insulating coating disposed on the body, and a surface finish of about 200 to about 2000 micro inches. And at least a portion of the coating disposed in the center of the surface.

  [0014] In one embodiment, the substrate support includes a body having a substrate support surface, a substrate support structure having one or more supports adapted to structurally support the body during processing, and It is adapted to support large area substrates with an insulating coating disposed on the substrate support surface that has been treated after deposition on a surface finish of 200 to about 2000 microinches.

  [0015] In another embodiment, the substrate support provides an aluminum body suitable for supporting a large area substrate on the substrate support surface, and an anode having a surface roughness of about 330 to about 2000 microinches. Forming a curable coating on the substrate support surface.

  [0016] In yet another embodiment, the substrate support is adapted to support a large area substrate comprising a conductive body having a substrate support surface, wherein the substrate support surface is bare aluminum. It has a surface finish of about 140 to about 2000 microinches.

  [0017] In yet another embodiment, the substrate support has a substrate support surface treated with a surface finish of about 140 to about 1000 microinches and structurally supports the aluminum body during processing. And is adapted to support a large area substrate comprising a substrate support structure having one or more supports adapted to.

  [0018] A more specific description of the invention, briefly summarized above, may be made by reference to the embodiments illustrated in the accompanying drawings. However, the attached drawings illustrate only typical embodiments of the invention, and therefore the invention should not be construed as limiting the scope thereof as it may recognize equally effective embodiments. Should be noted.

  [0031] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the drawings.

Detailed description

[0032] The present invention generally provides large area substrate supports and methods of manufacturing the same. The present invention relates to a plasma enhanced chemical vapor deposition system for processing large area substrates, such as a plasma enhanced chemical vapor deposition (PECVD) system available from AKT, a division of Applied Materials, Inc. of Santa Clara, California. Reference will be made to a case example below. In one embodiment, the processing chamber is adapted to process large area substrates having a surface area of at least about 2000 cm ² . In another embodiment, the processing chamber is adapted to process a substrate having a surface area of at least about 6,716 cm ² (eg, 730 mm × 920 mm). However, the present invention is practical in other system configurations such as physical vapor deposition systems, ion implantation systems, etching systems, other chemical vapor deposition systems, and other systems where it is desirable to process a substrate on a substrate support. It should be understood that it has sex.

  FIG. 1 is a cross-sectional view of one embodiment of a plasma enhanced chemical vapor deposition system 100. System 100 generally includes a chamber 102 coupled to a gas source 104. The chamber 102 has a wall 106 that defines a process volume 112, a bottom 108, and a lid assembly 110. Process volume 112 is typically accessed through a port (not shown) in wall 106 that facilitates movement of large area glass substrate 140 relative to chamber 102. Wall 106 and bottom 108 are typically manufactured from unitary blocks of aluminum or other materials compatible with processing. The lid assembly 110 includes a pump plenum 114 that couples the process volume 112 to an exhaust port (not shown) coupled to various pump components (not shown).

  [0034] The lid assembly 110 is supported by the wall 106 and can be removed to service the chamber 102. The lid assembly 110 is generally constructed from aluminum. A distribution plate 118 is coupled to the inside 120 of the lid assembly 110. Distribution plate 118 is typically manufactured from aluminum. The central section includes a perforated area where the process and other gases supplied from the gas source 104 are routed to the process volume 112. The perforated area of distribution plate 118 is configured to provide a uniform distribution of gas passing through chamber 102 through distribution plate 118.

  [0035] The substrate support assembly 138 is centrally located within the chamber 102. The substrate support assembly 138 supports the large area glass substrate 140 (hereinafter “substrate 140”) during processing.

Coating susceptor design
[0036] In one embodiment, the substrate support assembly 138 generally includes a conductive body 124 that is covered by an insulating coating 180 over at least a portion of the body 124 that supports the substrate 140. Insulative coating 180 has a surface finish of about 200 to about 2000 microinches and is believed to improve deposition uniformity without expensive aging or plasma treatment of substrate support assembly 138. The surface finish is characterized by average surface roughness (Ra) or arithmetic average (AA). Insulative coating 180 may also cover other parts of body 124. A rougher surface can counteract the effects of glass substrate thickness variations, provide more uniform capacitance across the substrate, increase plasma and deposition uniformity, and substantially reduce the formation of thin spots in the deposited film. Seems to be eliminated.

  [0037] Also, a small contact between the substrate and the insulative coating 180 reduces the charge transfer provided by the small contact surface area, or an increase in roughness improves the electrical contact that reduces the charge difference between the two parts. As such, the possibility of ESD metal line arc and particle attraction to the substrate surface is reduced.

  [0038] The conductive body 124 is fabricated from metal or other equivalent conductive material. Insulative coating 180 may be a dielectric metal such as oxide, silicon nitride, silicon dioxide, aluminum dioxide, tantalum pentoxide, silicon carbide, polyimide, among others, flame spray, plasma spray, high energy coating, It may be applied by a variety of deposition or coating processes including but not limited to chemical vapor deposition, spraying, adhesion films, sputtering and encapsulation.

  In one embodiment, the substrate support assembly 138 includes an aluminum conductive body 124 that encapsulates at least one embedded heating element 132 and a thermocouple 190. At least one first reinforcing member 116 is generally embedded in the body 124 proximate the heating element 132. The second reinforcing member 166 may be disposed in the main body 124 on the side surface of the heating element 132 that faces the first reinforcing member 116. The reinforcing members 116 and 166 may be constructed from metal, ceramic or other rigid material. In one embodiment, the reinforcing members 116 and 166 are comprised of aluminum oxide fibers. Alternatively, the reinforcing members 116 and 166 may be composed of aluminum oxide fiber, silicon carbide fiber, silicon oxide fiber or similar material associated with aluminum oxide particles. Reinforcing members 116 and 166 may include a loose material or may be a prefabricated shape such as a plate. Alternatively, the reinforcing members 116 and 166 may have other shapes and forms. Generally, the reinforcing members 116 and 166 have a porosity that immerses the members 116, 166 in aluminum during the casting process described below.

  [0040] A heating element 132, such as an electrode, disposed on the substrate support assembly 138 is coupled to the power source 130 to heat the substrate support assembly 138 and the substrate 140 positioned thereon in a controllable manner to a predetermined temperature. To do. Typically, the heating element 132 maintains the substrate 140 at a uniform temperature of about 150 to at least about 460 degrees Celsius.

  [0041] In general, the substrate support assembly 138 has a lower side 126 and an upper side 134 that supports the substrate. The lower side 126 has a stem cover 144 coupled thereto. The stem cover 144 is typically an aluminum ring coupled to a substrate support assembly 138 that provides a mounting surface for attachment of the stem 142.

  [0042] Generally, the stem 142 extends from the stem cover 144 and causes the substrate support assembly 138 to be lifted (not shown) to move the substrate support assembly 138 between a high position (as shown) and a low position. Combine. Bellows 146 facilitates movement of support assembly 138 while providing a vacuum seal between process volume 112 and the atmosphere outside chamber 102. The stem 142 additionally provides a conduit for electrical and thermocouple leads between the substrate support assembly 138 and other components of the system 100.

  [0043] RF power supplied by the power source 122 to the distribution panel 118 (or other electrodes positioned in or near the chamber lid assembly) is placed in the process volume 112 between the substrate support assembly 138 and the distribution plate 118. The substrate support assembly 138 is generally grounded so as to excite the generated gas. The RF power from the power source 122 is generally selected according to the size of the substrate to drive the chemical vapor deposition process.

  [0044] The substrate support assembly 138 additionally supports the circumscribing shadow frame 148. In general, the shadow frame 148 prevents deposition on the edges of the substrate 140 and substrate support assembly 138 so that the substrate does not adhere to the support assembly 138.

  [0045] The substrate support assembly 138 has a plurality of holes 128 disposed therethrough for receiving a plurality of lift pins 150. The lift pins 150 are usually made of ceramic or anodized aluminum. In general, the lift pins 150 are substantially flush with or from the upper side 134 of the substrate support assembly 138 when the lift pins 150 are in a normal position (ie, retracted relative to the support assembly 138). It has a first end 160 that is slightly retracted. The first end 160 is generally flared to prevent the lift pin 150 from falling out of the hole 128. In addition, the lift pin 150 has a second end 164 that extends beyond the lower side 126 of the support assembly 138. The lift pins 150 may be activated relative to the substrate support assembly 138 by the lift plate 154 so as to protrude from the upper side 134, thereby allowing the substrate to be spaced from the support assembly 138.

  [0046] The lift plate 154 is disposed proximate to the lower side 126 of the support surface. The lift plate 154 is connected to the actuator by a collar 156 that circumscribes a portion of the stem 142. Bellows 146 includes an upper portion 168 and a lower portion 170 that move stem 142 and collar 156 independently while maintaining separation of process volume 112 from the environment outside chamber 102. In general, the lift plate 154 is activated to extend the lift pins 150 from the upper side 134 as the substrate support assembly 138 and the lift plate 154 move toward each other.

  [0047] FIGS. 2 and 2A are partial cross-sectional views of another embodiment of a substrate support assembly 138, which is hereinafter labeled with a support assembly 200 to avoid confusion. The support assembly 200 may include aluminum and includes a body 202 that is substantially covered by an anodized coating 210. The body 202 may be composed of one or more coupling members and a single cast body having heating elements 132 embedded therein. Examples of substrate support assemblies that can be adapted to enjoy the benefits of the present invention include US patent application Ser. No. 10 / 308,385 filed Dec. 2, 2002, and filed Aug. 1, 2001. No. 09 / 921,104, both of which are incorporated herein by reference in their entirety.

  [0048] The body 202 generally includes a substrate support surface 204 and an opposing mounting surface 206. The mounting surface 206 is coupled to a stem 142 (seen in FIG. 1). The anodized coating 210 covers at least the substrate support surface 204 of the body 202 and provides a separation layer between the substrate 140 and the substrate support surface 204.

  [0049] Referring to FIG. 2A, the coating 210 includes an outer surface 212 and an inner surface 214. The inner surface 214 is generally disposed directly on the body 202. In one embodiment, the anodized coating has a thickness of about 0.3 mil (7.6 micrometers) to about 2.16 mil (54.9 micrometers). Anodized coatings with thicknesses outside this range may fail during temperature cycling or may not significantly reduce spotting of large area films of SiN, αSi and n + α-Si formed by PECVD deposition.

  [0050] Referring to FIGS. 2 and 2A, a portion 218 of the outer surface 212 positioned on the substrate support surface 204 has a configuration configured to support the substrate 140 thereon. A portion 218 of the outer surface 212 has a specific roughness coating surface finish 216 that promotes a uniform thickness of the film deposited on the substrate 140. The coating surface finish 216 has a roughness of about 200 to about 2000 microinches. The coating surface finish 216 advantageously results in improved film thickness uniformity and substantially eliminates local thickness non-uniformity (thin deposition spots) without actually adjusting (eg, aging) the substrate support. Is known to be eliminated. The elimination of substrate support adjustment saves both the time and material normally consumed in the plasma aging process, eliminating the vacuum purge between cycles, which results in improved system throughput. In one embodiment, the coating surface finish 216 has a roughness of about 330 microinches.

  [0051] The coating surface finish 216 of the anodized coating 210 may additionally / or (to obtain a particular surface finish 208) by treating at least a portion 220 of the external substrate support surface 204 underlying the substrate 140. And / or) by at least treating the anodized coating 210 that supports the substrate 140. The surface finish 208 of the substrate support surface 204 is formed in a number of ways, including bead blasting, grinding blasting, grinding, embossing, sanding, texturing, etching, or other methods to provide specific surface roughness. May be. In one embodiment, the surface finish 208 of the substrate support surface 204 of the body 202 is about 200 to about 2000 microinches. In another embodiment, the surface finish 208 is about 330 microinches.

  [0052] Optionally, the strip 224 of the substrate support surface 204 adjacent the portion 220 positioned from below the substrate 140 may be left untreated to minimize manufacturing costs. This results in a strip 222 of anodized coating 210 above the untreated strip 224 that may have a different finish than the finish 216, but when the strip 222 exceeds the substrate 140, the surface finish of the strip 222. Does not affect the uniformity of film deposition. In one embodiment, the strip 222 of the anodized coating 210 has a smoother surface finish than the portion 218 of the anodized coating 210 that it is adjacent to.

  [0053] FIG. 3 depicts one embodiment of a method 300 of manufacturing the support assembly 138. The method begins at step 302 by preparing the substrate support surface 204 of the body 202. Since the preparatory step 302 generally involves actuating or otherwise treating the substrate support surface 204, the surface finish 208 is about 200 to about 2000 microinches. The surface finish 208 is characterized by an average surface roughness (Ra) and an arithmetic average (AA). In one embodiment, the preparation step 302 includes bead blasting, grinding blasting, grinding, embossing, sanding, texturing, etching, or other methods for providing a specific surface roughness of, for example, about 330 microinches. May be included. It is common to use milling, lathe cutting, knurling, frame cutting, or other similar metal removal techniques to achieve a surface roughness greater than 500 microinches to about 2000 microinches.

[0054] In one embodiment of step 302, the substrate support surface 204 is made of, for example, aluminum (Al), alumina (Al ₂ O ₃ ) to achieve a desired roughness in the range of about 200 to about 2000 microinches. A flame, arc or plasma sprayed with materials such as titanium (Ti) or stainless steel. In one aspect, the substrate support surface 204 is coated with an arc sprayed aluminum material to achieve a roughness of about 200 to about 2000 micro inches.

  [0055] In one embodiment, the substrate support surface 204 is bead blasted to a predetermined surface finish. The bead blasting may include impacting the garnet, ceramic or glass beads against the body 202.

  [0056] In another embodiment, the beads are aluminum oxide having an average diameter of about 125 to about 375 microns. The beads are provided through a nozzle having an exit velocity sufficient to produce a surface finish 208 of about 200 to about 2000 microinches.

  [0057] After completion of the preparation step 302, the body is anodized at step 304. Anodization step 304 generally includes applying an anodization layer having a thickness of about 0.3 to about 2.16 mils. The resulting coating surface finish 216 on the outer surface 210 of the anodized coating 212 is about 200 to about 2000 microinches, preferably about 300 to about 1000 microinches, more preferably about 330 to about 500 microinches. .

  [0058] FIG. 4 depicts another embodiment of a method 400 of manufacturing the support assembly 138. The method begins at step 402 by anodizing the body 202. At step 404, at least a portion 218 of the outer surface 212 of the anodized coating 210 is treated to provide a roughened coating surface finish 216. Alternatively, other parts of the outer surface 212 may be treated.

  [0059] The treatment step 404 may include bead blasting, grinding blasting, grinding, milling, embossing, sanding, texturing, etching, or other methods for providing a specific surface roughness. In one embodiment, treatment step 404 results in a surface finish of about 200 to about 2000 microinches, preferably about 300 to about 1000 microinches, more preferably about 330 to about 500 microinches.

  [0060] FIG. 5 depicts a partial cross-sectional view of another embodiment of a support assembly 500 configured to increase uniform deposition thickness. Support assembly 500 includes an aluminum support body 502 substantially encapsulated by an anodized coating 506. The heating element 504 is coupled to the support body 502 to control the temperature of the substrate 140 positioned on the upper surface of the support assembly 500. The heating element 504 may be a resistance heater or other temperature control device coupled to or disposed relative to the body 502. Alternatively, the lower portion 512 of the body 502 may not be anodized to provide direct contact between the heating element 504 and the body 502. In some cases, an intermediate layer (not shown) of thermally conductive material may be disposed between the heating element 504 and the lower portion 512 of the body 502.

  [0061] The upper portion 508 of the anodized coating 506 that supports the substrate 140 has a surface finish 510 configured to enhance uniform deposition of the film on the substrate 140. In one embodiment, the surface finish 510 has a roughness of about 200 to about 2000 microinches, preferably about 300 to about 1000 microinches, more preferably about 330 to about 500 microinches. The surface finish 510 may be created by a number of methods including those described above.

  [0062] FIG. 6 depicts another embodiment of a heater assembly 600. FIG. The heater assembly 600 includes an aluminum body 602 on which an anodized coating 606 is at least partially formed. A heating element 604, a conduit through which a temperature controlled fluid is circulated, is positioned relative to the bottom surface of the body 602 to facilitate temperature control of the substrate 140. In some cases, a thermally conductive plate 614 may be disposed between the heating element 604 and the body 602 to increase temperature uniformity between the heating element 604 and the body 602. In one embodiment, the thermally conductive plate 614 is a copper plate.

  [0063] The clamp plate 608 is coupled to the body 602 by a plurality of fasteners 610 (one of which is shown in FIG. 6) that thread-connects within thread holes 612 formed in the body 602. The clamp plate 608 can enhance heat transfer by sandwiching the heating element 604 with the main body 602.

  [0064] The portion 620 of the anodized coating 606 that supports the substrate 140 has a surface finish 622 configured to enhance uniform deposition of the film on the substrate 140. The surface finish 622 may be created in the same manner as described above.

  [0065] Accordingly, a support assembly is provided that enhances uniform deposition of films disposed on large area substrates. Time aging of the support assembly and its relatedness by at least a portion of the anodized coating covering the aluminum body of the support assembly supporting the substrate being textured to a predetermined surface roughness that enhances deposition uniformity Cost can be substantially eliminated.

Uncoated susceptor
[0066] FIGS. 7 and 7A are partial cross-sectional views of another embodiment of a substrate support assembly 138 that is uncoated and hereafter classified as a substrate support assembly 700 to avoid confusion. . Support assembly 700 includes a bare or uncoated body 702. The body 702 may be composed of one or more coupling members, or a unitary casting body having a heating element 132 embedded therein. In one embodiment, the body 702 is made from a metal such as, for example, aluminum (Al), titanium (Ti), or stainless steel.

  [0067] The body 702 generally includes a substrate support surface 704 and an opposing mounting surface 706. Mounting surface 760 is coupled to stem 142 (seen in FIG. 1).

  [0068] Referring to FIGS. 7 and 7A, the substrate support surface 704 has a configuration configured to support the substrate 140 thereon. The substrate contact portion 720 of the substrate support surface 704 has a specific roughness surface finish 714 that promotes a uniform thickness of the film deposited on the substrate 140. The surface finish 714 has a roughness of about 80 to about 2000 microinches. It has been found that the surface finish 714 advantageously provides improved film thickness uniformity and, in fact, substantially eliminates local thickness non-uniformities (thin deposition spots). In one embodiment, surface finish 714 has a roughness greater than about 140 microinches. In another embodiment, surface finish 714 has a roughness greater than about 340 microinches. In one aspect, to reduce the cost of forming the substrate support assembly 700, the substrate contact portion 720, the side edges 734, and the area 722 outside the opposing mounting surface 706 are roughened or partially roughened. It is desirable to leave the state as it is.

  [0069] FIG. 8 depicts one embodiment of a method 800 of manufacturing the support assembly 138. The method begins at step 802 by providing a support surface 704 for the body 702. Since the preparation step 802 generally involves actuating or otherwise treating the support surface 704, the surface finish 714 is about 140 to about 2000 microinches, preferably about 300 to about 1000 microinches, more preferred. More preferably from about 330 to about 500 microinches. The finish 714 is characterized by an average surface roughness (Ra) or an arithmetic average (AA). In one embodiment, the preparation step 802 includes bead blasting, grinding blasting, grinding, embossing, sanding, texturing, etching, or other methods for providing a specific surface roughness of, for example, about 330 microinches. You may go out. It is common to use milling, lathe cutting, knurling, frame cutting, or other similar metal removal techniques to achieve a surface roughness greater than 500 microinches to about 2000 microinches.

  [0070] In one embodiment, an optional surface coating step 804 is used to form a rough surface on which the substrate is supported. The surface coating step 804 is a conventional frame, arc, or plasma spray such as aluminum (Al), titanium (Ti) or stainless steel to achieve the desired roughness in the range of about 140 to about 2000 microinches. It may be performed on the support surface 704 by the use of metal. In one aspect, the support surface 704 of the body 702 made from aluminum is coated with an arc spray aluminum material to achieve a roughness greater than about 140 microinches.

[0071] In another embodiment of optional step 804, the ceramic or metal oxide coating is supported by use of a conventional flame, arc or plasma spray process to achieve a surface roughness of about 80-2000 microinches. Deposited on the surface 704. For example, aluminum oxide (Al ₂ O ₃ ) may be deposited on the support surface 704 to achieve a surface roughness of about 140 to about 2000 microinches.

Substrate support structure
[0072] The various aspects of the present invention discussed above generally improve substrate process results on large area substrates by improving various properties and characteristics (eg, elements 138, 200, 700) of the substrate support assembly. Various embodiments that can be discussed are discussed. In order to achieve the desired and repeatable process results on large area substrates, it is generally necessary to ensure that the contact between the substrate and the substrate support is relatively uniform and repeatable. In order to ensure that the contact is relatively uniform and repeatable, the substrate support surface generally needs to be formed and left in the desired and repeatable shape. Referring to FIGS. 9 and 10, the structure support (eg, element 910) is provided to the substrate support 902 by the size of the substrate structure 910 and the temperatures typically achieved during processing (eg, typically between 150 ° C. and 460 ° C.). Thus, it may often be required to prevent deflection due to gravity and softening of the material from which the substrate support 902 is formed. This problem usually arises when using a substrate support 902 made from aluminum due to the nature of the aluminum material at these temperatures. An exemplary design of the support structure essential to the substrate support 902 adapted to resist deflection during high temperature processing is further described in commonly assigned US Pat. No. 6,554,907, This is incorporated herein by reference in its entirety as long as it does not conflict with the claimed invention. An exemplary design of an essential support structure for a substrate support 902 adapted to resist deflection during high temperature processing is described in commonly assigned US patent application Ser. No. 11 filed Jun. 2, 2005. No./143,506 [AMAT 9182], which claims the benefits of US Provisional Patent Application No. 60 / 587,173, filed July 12, 2004, and claims The entire contents of which are hereby incorporated by reference as long as they are consistent with the invention described.

  [0073] FIG. 9 illustrates an exploded isometric view of a substrate support structure 910 that may be used in place of the substrate support assembly 138 shown in FIG. FIG. 10 illustrates a side view of a fully assembled oriented substrate support structure 910 having a substrate 140 positioned on a substrate support surface 904. The substrate support structure 910 of FIGS. 9 and 10 generally includes a base structure 914 below the substrate support 902. In one aspect, the substrate support 902 is supported by a base structure 914 that is connected and supported by a shaft 142 at a connection point 901. In one embodiment, the base structure 914 provides continuous support to the substrate support 902 to ensure that the substrate support surface 904 remains in the desired predetermined shape before, during and after various processes. It is adapted to guarantee. The substrate support 902 described in connection with the support structure 910 can generally be formed by any of the processes described above (eg, described in connection with elements 202, 502, 602, 702).

[0074] The base structure 914 generally contains an elongated base support plate 915 and a plurality of horizontal support plates 917 adapted to support the substrate support 902. In the configuration shown in FIG. 9, the horizontal support is arranged in an orientation that is substantially perpendicular to the base support plate 915. In one aspect, the plates 915, 917 are preferably made from a material that is strong and rigid enough to support and hold the weight of the substrate support 902 under processing temperature and pressure conditions. For example, the plates 915, 917 are made of a ceramic material such as alumina (Al ₂ O ₃ ) or a refractory metal such as 300 series stainless steel.

  [0075] Although the drawing of FIG. 9 shows the substrate support structure 910 disassembled for illustrative purposes, it is understood that the substrate support 902 is stationary immediately above the support plates 915, 917. It is assumed that the substrate support 902 and the support plates 915, 917 do not move relative to each other during processing. Also, referring to FIG. 9, one base support plate 915 and four individual horizontal support plates 917 are shown, whereas any number of support plates 915, 917 may be used. Should be understood.

  [0076] In one embodiment, the base structure 914 may be formed in a non-planar shape to provide a non-planar profile to the substrate support 902 and the supported substrate 140 (see FIG. 10). In this embodiment, the base structure 914 supports an elongated base support plate 915, a plurality of horizontal support plates 917 disposed substantially perpendicular to the base support plate 915, a substrate support 902, and a desired non- It may contain a plurality of shims 918 of varying thickness placed on a horizontal support plate 917 to achieve a planar profile. Preferably, the shim 918 has a thickness of about 0.4 mm to about 3.5 mm. In this embodiment, the shim 918 is positioned at the end of the horizontal support plate 917, but the shim 918 may be disposed at other portions of the horizontal support plate 917. The shape of the support plate 917 and / or the use of shims 918 can be achieved by pre-forming the substrate support 902 that converts the desired planar orientation relative to the substrate during processing because the heated substrate follows the planar orientation of the substrate support 902 during processing. It is assumed to be acceptable.

  [0077] Although several preferred embodiments have been shown and described in detail which incorporate the teachings of the present invention, those of ordinary skill in the art will readily devise numerous other various embodiments that still incorporate these teachings. can do.

1 depicts a schematic cross-sectional view of one embodiment of a processing chamber having a substrate support assembly of the present invention. FIG. 6 is a partial cross-sectional view of another embodiment of a substrate support assembly. FIG. 6 is a partial cross-sectional view of another embodiment of a substrate support assembly. 5 is a flowchart of an embodiment of a method for manufacturing a substrate support assembly. 6 is a flowchart of another embodiment of a method for manufacturing a substrate support assembly. FIG. 6 is a partial cross-sectional view of another embodiment of a substrate support assembly. FIG. 6 is a partial cross-sectional view of another embodiment of a substrate support assembly. FIG. 6 is a partial cross-sectional view of another embodiment of a substrate support assembly. FIG. 6 is a partial cross-sectional view of another embodiment of a substrate support assembly. 5 is a flowchart of an embodiment of a method for manufacturing a substrate support assembly. 2 is an exploded isometric view of a substrate support assembly in one embodiment. FIG. FIG. 10 is a side view of the substrate support assembly of FIG. 9.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... System, 102 ... Chamber, 104 ... Gas source, 106 ... Wall, 108 ... Bottom, 110 ... Lid assembly, 112 ... Process volume, 114 ... Pump plenum, 116 ... Reinforcement member, 118 ... Distribution plate, 120 ... Inside, 122 ... Power source, 124 ... Body, 126 ... Lower side, 128 ... Hall, 130 ... Power source, 132 ... Heating element, 134 ... Upper side, 138 ... Substrate support assembly, 140 ... Substrate, 142 ... Stem, 144 ... Stem cover, 146 ... Bellows, 148 ... Shadow frame, 150 ... Lift pin, 154 ... Lift plate, 156 ... Collar, 160 ... First end, 164 ... Second end, 166 ... Reinforcing member, 168 ... Upper part, 170 ... Lower part 180 ... Insulating coating, 190 ... Thermocouple, 200 ... Support assembly 202 ... Body 204 ... Substrate support surface 206 ... Opposite mounting surface 208 ... Surface finish 210 ... Anodized coating 212 ... Outer surface 214 ... Inner surface 216 ... Coated surface finish 218 ... Portion 220 ... Part, 222 ... strip, 224 ... strip, 300 ... method, 302 ... step, 304 ... step, 400 ... method, 402 ... step, 404 ... step, 500 ... support assembly, 502 ... aluminum support body, 504 ... heating element, 506 ... anodized coating, 508 ... upper part, 510 ... surface finish, 512 ... lower part, 600 ... heater assembly, 602 ... aluminum body, 604 ... heating element, 606 ... anodized coating, 608 ... clamp plate, 610 ... Fasteners, 612 ... Red hole, 614 ... thermally conductive plate, 620 ... part, 622 ... surface finish, 700 ... support assembly, 702 ... main body, 704 ... substrate support surface, 706 ... mounting surface, 714 ... surface finish, 720 substrate contact part , 722 ... Area, 734 ... Side edge, 800 ... Method, 802 ... Step, 804 ... Step, 901 ... Connection point, 902 ... Substrate support, 904 ... Substrate support surface, 910 ... Substrate support structure, 914 ... Base structure 915 ... Base support plate, 917 ... Horizontal support plate, 918 ... Shim.

Claims (24)

A substrate support adapted to support a large area substrate,
A conductive body having a substrate support surface;
An insulating coating disposed on the body;
At least a portion of the coating disposed in the middle of the substrate support surface, the average surface roughness (Ra) having a surface finish of 330-2000 microinches;
With a substrate support.   The substrate support of claim 1, wherein the conductive body is at least partially fabricated from an aluminum body and the coating is an anodized layer.   The substrate support according to claim 2, wherein the anodized coating has a thickness of 0.3-2.16 mils.   The substrate support of claim 1, wherein the substrate support surface has a surface finish with an average surface roughness of 330 to 500 microinches.   The substrate support of claim 4, wherein the substrate support surface is bead blasted. The coating disposed on the substrate support surface further comprises:
The substrate support of claim 1, comprising a strip circumscribing the portion of the coating in the center of the substrate support surface and having a surface finish having an average surface roughness of less than 200 microinches. The substrate support surface further includes
A central region having a surface finish with an average surface roughness of 330 to 500 microinches;
A peripheral region circumscribing the central region and having a surface finish with an average surface roughness of less than 300 microinches;
The substrate support according to claim 1, comprising: The substrate support of claim 1, wherein a surface area of the substrate support surface is at least 2,000 cm ² . A substrate support adapted to support a large area substrate,
A body having a substrate support surface;
A substrate support structure having one or more supports adapted to structurally support the body during processing;
An insulating coating disposed on the substrate support surface, wherein after the deposition, the insulating coating is treated with a surface finish having an average surface roughness (Ra) of 330-2000 microinches;
With a substrate support.   The substrate support of claim 9, wherein the body is aluminum and the coating is an anodized layer.   The substrate support surface is treated by at least one of bead blasting, grinding blasting, grinding, embossing, sanding, texturing, etching, milling, lathe cutting, knurling or frame cutting. Board support as described.   The substrate support of claim 9, wherein the substrate support surface is blasted with an aluminum oxide medium having an average diameter of 125 to 375 microns. Providing a conductive body having a substrate support surface adapted to support a large area substrate;
Coating the substrate support surface, wherein the coating is an anodized coating performed on the conductive body containing aluminum, the coating having an average surface roughness (Ra) of 330 to 1000 microinches; A substrate support manufactured by a process comprising: The step of providing a conductive body assembly further comprises:
Providing a substrate support structure having one or more supports;
Positioning the conductive body on the one or more supports;
The substrate support of claim 13, comprising:   The substrate support of claim 13, further comprising treating the substrate support surface prior to coating to provide a surface finish on the body with an average surface roughness of 300 to 2000 microinches. The step of treating the substrate support surface further comprises at least one selected from the group consisting of bead blasting, grinding blasting, grinding, embossing, sanding, texturing, etching, milling, lathe cutting, knurling and frame cutting. The substrate support of claim 15 , comprising performing one procedure. The step of treating the substrate support surface further comprises:
Comprising the steps of bead blasting the substrate support surface, comprising the step of bead blasting includes the colliding beads having an average diameter of 125 to 375 microns on the substrate support surface to claim 15 Board support as described.   The substrate support of claim 13, further comprising encapsulating a heating element in the conductive body, wherein the conductive body contains aluminum.   The substrate support of claim 13, further comprising coupling a heating element to the conductive body opposite the substrate support surface. Treating an aluminum substrate support surface adapted to support a large area substrate to obtain a surface finish having an average surface roughness (Ra) of 300-2000 microinches;
Anodizing the substrate support surface to a thickness of 0.3-2.16 mils, wherein the surface finish of the anodized coating disposed on at least the central portion of the substrate support surface is an average Having a surface finish with a surface roughness of 330-2000 microinches;
Substrate support manufactured by a process comprising: A substrate support adapted to support a large area substrate,
A conductive body having a substrate support surface, wherein the substrate support surface is bare aluminum and is achieved using milling, lathe cutting, knurling, frame cutting, or other similar metal removal techniques. A substrate support comprising a conductive body having a surface finish with an average surface roughness (Ra) of 500 to 2000 microinches. A substrate support adapted to support a large area substrate,
A bare aluminum body having a substrate support surface treated with a surface finish having an average surface roughness (Ra) of 330-500 microinches;
A substrate support structure having one or more supports adapted to structurally support the aluminum body during processing;
With a substrate support. The substrate support surface is bead blasted, grinding blasting, grinding, embossing, sanding, texturing, etching, milling, lathe cutting, is treated by a process selected from the knurled and frame cutting, according to claim 22 Board support. 23. The substrate support of claim 22 , wherein the substrate support surface is blasted with an aluminum oxide medium having an average diameter of 125 to 375 microns.

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