Substrate support apparatus

Abstract

A substrate support apparatus includes a rotary chuck and a plurality of positioning pins. The rotary chuck is used to support and rotate a substrate and has a support surface. The positioning pins are disposed at the periphery of the support surface and are used to limit horizontal displacement of the substrate. The support surface has a first annular region. The first annular region is divided into a plurality of pin regions and a plurality of non-pin regions. The plurality of pin regions and the plurality of non-pin regions are arranged alternately in the circumferential direction of the first annular region. Each pin region corresponds to one positioning pin. A plurality of Bernoulli holes are disposed in the first annular region and are configured in a non-uniform structure so as to be able to provide stronger gas flow in the pin regions than in the non-pin regions.

Description

Technical Field

[0001] The present invention relates to a substrate support device, and more specifically, to a substrate support device that supports a substrate using Bernoulli's principle, which prevents processing liquid from reaching the lower surface and edges of the substrate. Background Technology

[0002] Bernoulli chucks typically hold and support substrates without direct contact, especially during back-side substrate processing, minimizing chuck contamination. In back-side substrate processing, a processing solution is sprayed onto the back of the substrate to treat its surface, but it is not permitted to reach the front or edges. However, during the process, the processing solution can easily flow along the locating pins used to limit horizontal displacement of the substrate towards the front, resulting in what is known as "pin marks" on the front of the substrate near the locating pins.

[0003] US Patent 6328846B1 addresses and solves the aforementioned problems by disclosing that each locating pin is associated with an independent nozzle, through which gas is ejected from under the substrate towards the corresponding locating pin area. The nozzle is located around and at a distance from the Bernoulli nozzle, which supplies gas to form an air cushion to suspend the substrate. This allows the processing fluid to be blown away before reaching the vicinity of the locating pin. However, the independent control of the nozzle and Bernoulli nozzle for each locating pin leads to complexity in the Bernoulli chuck structure and operation. Summary of the Invention

[0004] This invention proposes a substrate support device to solve the "pin marks" problem mentioned in the background art. According to one embodiment of the invention, the proposed substrate support device includes a rotary chuck for supporting and rotating a substrate; a plurality of locating pins for limiting horizontal displacement of the substrate; and a plurality of Bernoulli holes for supplying gas to the substrate from below, forming an air cushion that floats the substrate and adhering to it using the Bernoulli effect. The rotary chuck has a support surface on which a first annular region is defined. The first annular region is divided into a plurality of pin regions and a plurality of non-pin regions. The pin regions and non-pin regions are alternately arranged along the circumference of the first annular region. Each pin region corresponds to one locating pin. The Bernoulli holes are located in the first annular region and are configured in a non-uniform structure to provide a stronger airflow in the pin regions than in the non-pin regions. Specifically, the diameter or density of the Bernoulli holes near the locating pins is larger than in other regions, so that the airflow distributed to the vicinity of the locating pins is greater than in other regions, thereby making the airflow near the locating pins stronger and preventing the processing liquid from flowing along the locating pins to the edges and lower surface of the substrate. To further prevent the lower surface of the substrate from being processed, an annular protrusion is provided around the periphery of the rotary chuck to form a groove above the support surface. The annular protrusion not only changes the flow direction of the processing liquid to prevent it from rebounding to any position on the substrate surface, but also creates a gap between the inner wall of the annular protrusion and the substrate edge held in the groove, thereby forming a stronger protective airflow. All of these factors help reduce the risk of processing liquid flowing to the lower surface of the substrate and causing contamination on the substrate. Attached Figure Description

[0005] To make the present invention more readily apparent to those skilled in the art, preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, wherein:

[0006] Figure 1 A cross-sectional view of a substrate support device according to an exemplary embodiment of the present invention is shown;

[0007] Figure 2 A top view of an exemplary rotary chuck is shown;

[0008] Figure 3 A top view of another exemplary rotary chuck is shown;

[0009] Figure 4 A top view of another exemplary rotary chuck is shown;

[0010] Figure 5 A top view of another exemplary rotary chuck is shown;

[0011] Figure 6 A top view of a rotating chuck of another substrate support device according to an exemplary embodiment of the present invention is shown;

[0012] Figure 7 A cross-sectional view of another substrate support device is shown;

[0013] Figure 8 Another cross-sectional view of another substrate support device is shown;

[0014] Figure 9 A cross-sectional view of the substrate support device with the substrate slightly moved upwards is shown; and

[0015] Figure 10 A cross-sectional view of yet another substrate support device according to an exemplary embodiment of the present invention is shown. Detailed Implementation

[0016] refer to Figure 1 This illustration shows a substrate support device according to an exemplary embodiment of the present invention. The substrate support device includes a rotary chuck 100 configured to support and rotate a substrate. The rotary chuck 100 has a support surface 110 for supporting a substrate 001. A plurality of positioning pins 130 are arranged around the periphery of the support surface 110 and abut against the edge of the substrate 001 to limit the horizontal displacement of the substrate 001. The support surface 110 is the top surface of the rotary chuck 100 and is surrounded by the plurality of positioning pins 130. The substrate 001 is positioned above the support surface 110 of the rotary chuck 100, and at least one nozzle 003 is used to spray various processing liquids, such as SC-1, SC-2, SPM, HF, DIW, etc., onto the surface of the substrate 001.

[0017] like Figure 1 and Figure 2 As shown, a first annular region 150 is formed on the support surface 110 of the rotary chuck 100. A plurality of Bernoulli holes 160 are disposed within the first annular region 150. Each Bernoulli hole 160 is inclined relative to the central axis of the rotary chuck 100, adapted to supply gas to the lower surface of the substrate 001 to form an air cushion and generate the Bernoulli effect. Therefore, the substrate 001 can be attracted and suspended above the support surface 110 of the rotary chuck 100 without contacting the support surface 110. The plurality of Bernoulli holes 160 form a ring, and an inert gas or nitrogen gas is supplied by a gas supply line.

[0018] Typically, a rotary chuck 100 is fixed to a rotating shaft, which is connected to a drive device. The drive device can drive the rotary chuck 100 and the rotating shaft to rotate synchronously. At least one gas supply line is provided for supplying gas to holes, such as Bernoulli holes 160, formed in the rotary chuck 100. These features are known to those skilled in the art and therefore will not be repeated in this invention or shown in the accompanying drawings.

[0019] See Figure 2Based on the distance from the locating pin 130, the first annular region 150 is divided into multiple pin regions 151 and multiple non-pin regions 152. Each pin region 151 corresponds to one locating pin 130. The Bernoulli holes 160 are divided into multiple first groups of Bernoulli holes 161 and multiple second groups of Bernoulli holes 162. Each first group of Bernoulli holes 161 corresponds to one pin region 151, and each second group of Bernoulli holes 162 corresponds to one non-pin region 152. The first group of Bernoulli holes 161 is closer to the locating pin 130 than the second group of Bernoulli holes 162. The pin regions 151 and non-pin regions 152 are arranged alternately and symmetrically in the circumferential direction of the first annular region 150. The central angle θ of each pin region 151 is 5° to 10°. Notably, each locating pin 130 is located on the line connecting the center of its corresponding pin region 151 and the center of the first annular region 150. In this invention, a plurality of Bernoulli orifices 160 located in the first annular region 150 are configured in a non-uniform structure, such that the gas flow rate supplied by the first set of Bernoulli orifices 161 located in the pin region 151 is greater than the gas flow rate supplied by the second set of Bernoulli orifices 162 located in the non-pin region 152.

[0020] In this invention, the non-uniform structure of the Bernoulli holes 160 within the first annular region 150 is mainly manifested in the variation of the diameter or density of the Bernoulli holes 160 in different regions (such as pin region 151 or non-pin region 152) along the circumferential direction of the first annular region 150. When the total gas supply to the non-uniformly structured Bernoulli holes 160 of this invention is equal to the total gas supply to the uniformly structured Bernoulli holes on a conventional rotary chuck, in this invention, by changing the diameter or density of the Bernoulli holes 160 adjacent to the locating pin 130, a stronger airflow can be generated near the locating pin 130. That is, without changing the gas supply, by distributing more gas flow to the vicinity of the locating pin 130, a stronger local gas resistance is applied near the locating pin 130. This can prevent the processing liquid from etching the edges and lower surface of the substrate 001 over the entire circumference of the substrate, especially near the locating pin 130. Some embodiments of rotary chucks with non-uniformly structured Bernoulli holes will be described in detail below.

[0021] See Figure 2 An exemplary rotary chuck 100 for supporting a substrate is shown. The rotary chuck 100 has non-uniform Bernoulli holes 160 formed in a first annular region 150, wherein the density of a first group of Bernoulli holes 161 located in the pin region 151 is greater than the density of a second group of Bernoulli holes 162 located in the non-pin region 152. For example... Figure 2As shown, the density of the first group of Bernoulli holes 161 located in the pin region 151 is the same, and the density of the second group of Bernoulli holes 162 located in the non-pin region 152 is also the same, but less than the density of the first group of Bernoulli holes 161 located in the pin region 151. Preferably, the density of each group of first group of Bernoulli holes 161 can also be designed to gradually increase as the distance between the Bernoulli hole 161 and the corresponding locating pin 130 decreases, and the density of the second group of Bernoulli holes 162 in the non-pin region 152 maintains a set value, which is not greater than the minimum density of the first group of Bernoulli holes 161 in the pin region 151.

[0022] See Figure 3 Another exemplary rotary chuck 200 for supporting a substrate is shown. The rotary chuck 200 has non-uniform Bernoulli holes 260 formed in a first annular region 250, wherein the diameter of the first set of Bernoulli holes 261 located in the pin region 251 is larger than the diameter of the second set of Bernoulli holes 262 located in the non-pin region 252. For example... Figure 3 As shown, the diameters of the first group of Bernoulli holes 261 located in the pin region 251 are the same, and the diameters of the second group of Bernoulli holes 262 located in the non-pin region 252 are also the same, but smaller than the diameter of the first group of Bernoulli holes 261 located in the pin region 251. Preferably, the diameter of the first group of Bernoulli holes 261 in each pin region 251 can also be designed to gradually increase as the distance between the Bernoulli hole 261 and the corresponding locating pin 130 decreases, while the diameter of the second group of Bernoulli holes 262 in the non-pin region 252 maintains a set value, which is not greater than the minimum diameter of the first group of Bernoulli holes 261 in the pin region 251.

[0023] See Figure 4 Another exemplary rotary chuck 300 for supporting a substrate is shown. The rotary chuck 300 has non-uniform Bernoulli holes 360 formed in a first annular region 350. The diameter of the Bernoulli holes 360 in the first annular region 350 increases as the distance between the Bernoulli holes 360 and the locating pins 330 decreases. Figure 4 As indicated by the middle arrow.

[0024] See Figure 5 Another exemplary rotary chuck 400 for supporting a substrate is shown. The rotary chuck 400 has non-uniform Bernoulli holes 460 formed in a first annular region 450, wherein the density of the Bernoulli holes 460 in the first annular region 450 increases as the distance between the Bernoulli holes 460 and the locating pins 430 decreases. Figure 5 As indicated by the middle arrow.

[0025] In summary, regardless of whether the diameter or density of the Bernoulli holes in the pin region is greater than that in the non-pin region, or whether the diameter or density of the Bernoulli holes gradually increases as the Bernoulli holes get closer to the corresponding locating pins, the purpose is to increase the gas flow rate allocated to the area near the locating pins, making it exceed the gas flow rate allocated to other areas. This applies more gas flow rate and gas resistance to the area near the locating pins, preventing the processing liquid from flowing from the upper surface of the substrate to the edge of the substrate, or even the lower surface of the substrate, thus avoiding the appearance of "pin marks" on the substrate.

[0026] The present invention also provides another exemplary substrate support device. For example... Figure 6 and Figure 7 As shown, the substrate support device includes a rotary chuck 500 with a support surface 510 for supporting the substrate 001, and a plurality of Bernoulli holes 551 disposed in a first annular region 550 defined on the support surface 510. Since the non-uniform structure of the Bernoulli holes in this embodiment is consistent with the aforementioned (e.g., the non-uniform structure of the Bernoulli holes on the rotary chucks (100, 200, 300, 400), it will not be described again here. Similarly, a plurality of locating pins 530 are arranged around the periphery of the support surface 510, which clamp the substrate 001 by moving radially inward or release the substrate 001 by moving radially outward. Each locating pin 530 is disposed in a corresponding locating groove 531 opened on the rotary chuck 500, and each is connected to a drive device 532, such as a motor or cylinder, which drives the locating pin 530 to move radially along the support surface 510.

[0027] See you again Figure 6 and Figure 7 In this embodiment, the substrate support device further includes an annular protrusion 570 protruding upward from the periphery of the support surface 510 and a plurality of lifting holes 561. These lifting holes 561 are disposed in a second annular region 560 on the support surface 510. The plurality of lifting holes 561 are evenly distributed within the second annular region 560. The second annular region 560 is concentrically distributed with the first annular region 550 and is located inside the first annular region 550. Gas supplied through the lifting holes 561 is used to lift the substrate 001 and adjust the height between the substrate 001 and the support surface 510.

[0028] The annular protrusion 570 is detachably fixed to the support surface 510 of the rotary chuck 500. By replacing the annular protrusion with one of suitable size, the substrate support device can accommodate substrates of different sizes, such as 200mm or 300mm. Of course, the annular protrusion 570 and the rotary chuck 500 can also be integrally molded, such as... Figure 7 As shown.

[0029] like Figure 8As shown, the top surface 571 of the annular protrusion 570 is higher than the support surface 510, forming a groove 580. The support surface 510 serves as the bottom surface of the groove 580. When the substrate 001 is held within the groove 580 of the rotary chuck 500, two gaps are formed between the substrate 001 and the rotary chuck 500. The first gap 591 is formed between the inner sidewall 572 of the annular protrusion 570 and the edge of the substrate 001, and the second gap 592 is formed between the support surface 510 and the lower surface of the substrate 001.

[0030] A cover 002 is typically provided around the rotating chuck 500 to prevent processing fluid from splashing into the environment. If an annular protrusion 570 is not provided around the periphery of the support surface 110, such as Figure 1 As shown, some of the processing liquid sputtered onto the cover 002 may directly sputter onto the support surface 110, and then bounce off the substrate 001 through the gap between the substrate 001 and the support surface 110 onto the lower surface of the substrate 001, which would contaminate the lower surface of the substrate 001. Therefore, one of the functions of the annular protrusion 570 is to change the flow path of the processing liquid sputtered onto the cover 002 to prevent the processing liquid from bouncing off onto the lower surface of the substrate 001. See also Figure 8 After the processing liquid splashes onto the cover 002, it first splashes back to the top surface 571 of the annular protrusion 570, and then bounces upward without contacting any surface of the substrate 001, thereby avoiding contamination of the substrate surfaces that do not need to be treated by the processing liquid.

[0031] See Figure 10 The diagram shows another exemplary annular protrusion 670 on the rotary chuck 600. The outer edge of the top surface 671 of the annular protrusion 670 is chamfered; in other words, the outer edge of the top surface 671 of the annular protrusion 670 has a radially outward inclined surface 672. After the processing fluid rebounds from the housing 002 and splashes onto the inclined surface 672, the processing fluid will bounce back onto the housing 002 again and then be discharged.

[0032] Please see Figures 7 to 9 The inner diameter of the annular protrusion 570 gradually increases from the lower part to the upper part of the groove 580. By adjusting the height between the substrate 001 and the support surface 510, the size of the first gap 591 can be changed. Specifically, the inner sidewall of the annular protrusion 570 is arc-shaped, such as a circular arc or an elliptical arc, which facilitates the guidance of the gas ejected from the Bernoulli hole 551 and the lifting hole 561 out of the first gap 591.

[0033] like Figure 9 As shown, when the substrate 001 is raised, the first gap 591 between the edge of the substrate 001 and the inner sidewall 572 of the annular protrusion 570 widens, which can increase the gas flow rate discharged from the first gap 591, thereby forming better gas protection in the entire circumferential direction of the substrate 001.

[0034] In one embodiment, the method for holding the substrate by the substrate support device is described below.

[0035] Step 1: The robotic arm picks up a substrate and places it above the rotating chuck, aligning the center of the substrate with the center of the support surface.

[0036] Step 2: Gas at a first pressure is supplied to the lifting hole to lift the substrate and hold it in a first position above the support surface, then the robot arm is removed. When the substrate is in the first position, the height between the lower surface of the substrate and the support surface is no greater than the height of the groove. The height of the first position can be adjusted by changing the first pressure.

[0037] Step 3: Before shutting off the gas supply to the lift orifice, supply gas at a second pressure to the Bernoulli orifice to form an air cushion below the substrate, causing the substrate to float on the air cushion. The second pressure is lower than the first pressure, thereby causing the substrate to move slightly downward after the gas switch.

[0038] Step 4: When the substrate is stably positioned in the predetermined position, drive the positioning pin to move radially inward and abut against the edge of the substrate to limit the horizontal displacement of the substrate.

[0039] After the above steps are completed, at least one nozzle moves above the substrate and sprays the treatment liquid onto the substrate surface. At the same time, during the process, the protective gas always surrounds the entire circumference of the substrate. Since the diameter or density of the Bernoulli holes near the locating pins is greater than that of the Bernoulli holes in other areas, a protective gas with stronger airflow will be obtained near the locating pins. This can effectively prevent the treatment liquid from flowing from the upper surface of the substrate to the edge or lower surface of the substrate.

[0040] The above description of the present invention is for illustrative purposes. The specific embodiments described are not exhaustive or limiting of the invention, and various modifications and variations can be readily apparent from the teachings of the invention. These modifications and variations are obvious to those skilled in the art and are therefore included within the scope of protection of the invention as defined in the claims.

Claims

1. A substrate support device, characterized in that, include: A rotary chuck is used to support and rotate a substrate. The rotary chuck has a support surface for supporting the substrate, and a first annular region is formed on the support surface. Multiple locating pins are arranged around the support surface of the rotary chuck to limit the horizontal displacement of the substrate. The first annular area is divided into multiple pin areas and multiple non-pin areas. These multiple pin areas and multiple non-pin areas are arranged alternately in the circumferential direction of the first annular area, and each pin area corresponds to a positioning pin. as well as Multiple Bernoulli holes are disposed in the first annular region for supplying gas toward the substrate and adhering to the substrate by utilizing the Bernoulli effect. The multiple Bernoulli holes are configured in a non-uniform structure within the first annular region to provide a stronger airflow in the pin region than in the non-pin region.

2. The substrate support device according to claim 1, characterized in that, The central angle θ of each pin area is 5° to 10°.

3. The substrate support device according to claim 1, characterized in that, The density or diameter of Bernoulli orifices in the pin region is greater than that in the non-pin region.

4. The substrate support device according to claim 3, characterized in that, The density or diameter of the Bernoulli holes in each pin region gradually increases as the distance between the Bernoulli holes and the corresponding locating pins decreases.

5. The substrate support device according to claim 1, characterized in that, The diameter or density of the Bernoulli holes formed in the first annular region gradually increases as the distance between the Bernoulli holes and the locating pin decreases.

6. The substrate support device according to claim 1, characterized in that, Further includes: One ring protrudes upwards from the outer periphery of the support surface of the rotating chuck; A groove, defined by an annular protrusion and the support surface of a rotating chuck, is used to accommodate a substrate; The second annular region is set on the support surface of the rotating chuck and is located inside the first annular region; Multiple lifting holes are provided in the second annular area and are evenly distributed in the second annular area to adjust the height between the support surfaces of the substrate and the rotary chuck.

7. The substrate support device according to claim 6, characterized in that, The inner diameter of the annular protrusion increases from the lower part of the groove to the upper part.

8. The substrate support device according to claim 7, characterized in that, The inner wall of the annular protrusion is curved.

9. The substrate support device according to claim 6, characterized in that, The annular protrusion and rotating chuck can be detachably installed and fixed or integrally molded.

10. The substrate support device according to claim 6, characterized in that, The outer edge of the annular convex top surface is chamfered.

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