Substrate stage and magnetron sputtering apparatus provided with same

Abstract

The present invention provides a substrate stage (ST) capable of having both a function of heating a rectangular substrate to a predetermined temperature with good in-plane uniformity and a function of setting a predetermined temperature gradient between a central portion and an outer peripheral portion of the substrate. The rack main body (6) provided with the substrate is provided with a heater (7) for heating the substrate through heat conduction. The upper surface of the gantry body is divided into a central region (Cz) surrounding the center and a peripheral region (Sz) surrounding the central region. The peripheral region has a first peripheral region (Sz1) located on both sides of the central region in the Y-axis direction and a second peripheral region (Sz2) located on both sides of the first peripheral region in the X-axis direction. The central area, the first peripheral area and the second peripheral area are all provided with heaters, when the heaters work to heat the substrate, the heating amount of the first peripheral area is lower than that of the central area, and the heating amount of the second peripheral area is lower than that of the first peripheral area.

Description

Technical Field

[0001] The present invention relates to a substrate stage and a magnetron sputtering apparatus having the substrate stage, the substrate stage comprising: a stage body having a substrate with a rectangular outline disposed on its upper surface; and a heater disposed on the stage body to heat the substrate by heat conduction. Background Technology

[0002] In the manufacturing process of flat panel displays, there is a film deposition process to form various thin films on the surface of a rectangular glass substrate (hereinafter referred to as "substrate"). In the film deposition process, for example, a magnetron sputtering apparatus is sometimes used, in which multiple magnet units are arranged side by side with spacing in one direction on the side of a single target facing away from the sputtering surface. The size of the substrate to be deposited increases generation by generation (e.g., 2300mm x 2700mm for the G8.7 generation), while its thickness is also thin (e.g., 0.5mm). Sometimes a substrate stage is set in the vacuum chamber of the magnetron sputtering apparatus for depositing films on such substrates, and a stage body with a heater mounted on its upper surface is provided. The substrate can then be heated to a specified temperature range (e.g., a temperature range of 50°C to 200°C) by contact heat conduction from the stage body (e.g., see Patent Documents 1 and 2). For the heater, for example, a sheathed heater is used, in which a heating element such as a nichrome wire that heats up by means of electricity is installed inside a metal tube.

[0003] The heat output of the sheath heater depends on the power supplied by the power source (heater output). Therefore, it is known that a product, when the sheath heater is built into the main body of the test bench, divides the power supply circuit (system) into multiple parts, allowing adjustment of the heater output of each power supply circuit. Furthermore, by adjusting the heater output of each power supply circuit, even large-area substrates can be heated with good in-plane uniformity. However, research has found that even if the substrate is preheated to a specified temperature with good in-plane uniformity, depending on the type of target corresponding to the thin film to be formed, while the uniformity of the film thickness distribution after film formation does not change, the in-plane uniformity of the film (film resistivity, film stress, etc.) may actually decrease.

[0004] Through in-depth research, the inventors discovered that, especially when forming thin films such as tungsten or molybdenum films—high-melting-point metals suitable for electrode films—the film quality tends to deteriorate at the outer periphery of the substrate, resulting in impaired in-plane uniformity. This is presumably due to the following reason: A frame-shaped anode plate with ground potential is typically positioned around the target. Therefore, it is speculated that when a plasma atmosphere forms in the film-forming space between the target and the substrate, depending on the position of the magnet unit, the plasma may extend to the vicinity of the anode plate. The plasma-induced heat input at the outer periphery of the substrate (especially at both ends in the X-axis direction) will locally increase, leading to a relatively high substrate temperature and causing localized changes in the crystal structure.

[0005] Existing technical documents Patent documents [Patent Document 1] Japanese Patent Publication No. 2023-69659 [Patent Document 2] Japanese Patent Publication No. 2023-183724 Summary of the Invention The technical problem that the invention aims to solve In view of the above, the technical problem to be solved by the present invention is to provide a substrate stage and a magnetron sputtering apparatus having the substrate stage, wherein the substrate stage is capable of heating a large area substrate with a rectangular outline to a specified temperature with good in-plane uniformity, and of setting a specified temperature gradient between the central part and the outer periphery of the substrate.

[0006] means of solving technical problems To solve the above problems, the substrate stand of the present invention comprises: a stand body having a substrate with a rectangular outline disposed on its upper surface; and a heater mounted on the stand body to heat the substrate by heat conduction. The feature is that: the upper surface of the stand body is divided into a central region surrounding a center and a peripheral region surrounding the central region, with the X-axis and Y-axis directions being orthogonal to each other within the upper surface of the stand body. The peripheral region comprises: a first peripheral region located on both sides of the central region along the Y-axis direction, with its amplitude extending across both sides of the substrate disposed on the upper surface of the stand body along the X-axis direction; and a second peripheral region located on both sides of the central region along the X-axis direction, with its amplitude extending across both sides of the substrate disposed on the upper surface of the stand body along the Y-axis direction. Heaters are disposed in the divided central region, first peripheral region, and second peripheral region, and when each heater operates to heat the substrate, the heat generated in the first peripheral region is lower than the heat generated in the central region, and the heat generated in the second peripheral region is lower than the heat generated in the first peripheral region.

[0007] Furthermore, to solve the aforementioned technical problems, the magnetron sputtering apparatus of the present invention includes the aforementioned substrate stage located in a vacuum chamber. The magnetron sputtering apparatus is characterized by comprising: a target, which is disposed facing the substrate disposed on the main body of the stage; and an anode plate of ground potential disposed around the target; the target is composed of a single target material larger than the outline of the substrate, and a plurality of magnet units are arranged side by side with spacing along the X-axis on the side of the target opposite to the sputtering surface; and a driving device for synchronously reciprocating each magnet unit along the X-axis; and adjusting the heat generation of the first peripheral region, the second peripheral region, and the subdivided region based on the heat input to the substrate caused by plasma during the film deposition process, with the heat generation of the central region as a reference.

[0008] Using the above method, when the substrate is uniformly heated, the heat output of the central region of the platform body facing the central region of the substrate (i.e., the heater output density (W / cm²) corresponding to the area of ​​the central region) is determined according to the current heating temperature (e.g., 150°C). Furthermore, the heat output of the first peripheral region is set within, for example, 30% to 50% of that of the central region, and the heat output of the second peripheral region is set within, for example, 80% to 99% of that of the first peripheral region, according to the heating temperature. Thus, even large-area substrates can be heated with good uniformity across their entire surface (e.g., within a range of 150°C ± 5°C). Therefore, it can be used to preheat the substrate to a specified temperature when forming, for example, an aluminum film or a titanium film on the substrate surface.

[0009] On the other hand, if a predetermined temperature gradient (e.g., Δ100°C) is set for the substrate taking into account the localized heat input caused by plasma, then, based on the heating temperature of the central region, the heat generation of the first peripheral region is set to 30% to 50% of the heat generation of the central region, and the heat generation of the second peripheral region is set to less than 10% of the heat generation of the first peripheral region. This allows a temperature difference region to be formed at the outer periphery of the substrate, particularly at both ends in the X-axis direction, where the temperature decreases towards the substrate end, enabling heating of the substrate with a predetermined temperature gradient. Therefore, when forming, for example, a tungsten film or a molybdenum film on the substrate surface, the substrate can be heated with a predetermined temperature gradient taking into account the localized heat input caused by plasma. Here, the division of the central region of the substrate platform and the first and second peripheral regions surrounding this central region (the areas of the central region, the first peripheral region, and the second peripheral region) is determined experimentally in advance. For example, when forming a high-melting-point metal film on the substrate while uniformly heating its entire surface, a film degradation region occurring at the outer periphery of the substrate is identified. Correspondingly, the areas of the first peripheral area and the second peripheral area (distance from the outer periphery of the main body of the platform in the X-axis direction and the distance in the Y-axis direction) are respectively set, and the area enclosed by them is defined as the central area.

[0010] Thus, the present invention employs a structure that divides the substrate into a central region and a first peripheral region and a second peripheral region surrounding the central region, thereby varying the heat generation in each region. Therefore, it can simultaneously achieve the functions of uniformly heating a large-area rectangular substrate to a predetermined temperature based on the target type, and establishing a predetermined temperature gradient between the central portion and the outer periphery of the substrate. Furthermore, various types of thin films can be formed with good film thickness uniformity and film quality uniformity (i.e., good in-plane uniformity of film quality when forming tungsten or molybdenum films) using a single magnetron sputtering device. In other words, film formation can be performed by adjusting the in-plane temperature distribution of the substrate based on the heat input to the substrate caused by plasma during the film formation process.

[0011] In this invention, the following structure can also be adopted: the central region further comprises multiple subdivided regions on both sides in the X-axis direction. When other heaters located in each subdivided region also operate to heat the substrate, the heat generation of the subdivided regions will be lower than that of the central region. By changing the heat generation of the main body of the platform between the main region of the central region and the second peripheral region outside the subdivided regions in this way, the film quality can be further adjusted according to the heat input to the substrate caused by plasma during the film formation process, thereby further improving the in-plane uniformity. The area of ​​the subdivided regions can also be determined in advance through experiments. Attached Figure Description

[0012] Figure 1 This is a cross-sectional schematic diagram of a magnetron sputtering apparatus equipped with the substrate stage of this embodiment.

[0013] Figure 2 It is along Figure 1 Sectional view of line II-II in the middle.

[0014] Figure 3 This diagram illustrates the state of the substrate when it is heated. Detailed Implementation

[0015] Referring to the accompanying drawings, embodiments of the substrate stage ST and the magnetron sputtering apparatus SM equipped with the substrate stage ST of the present invention will be described below using a product in a magnetron sputtering apparatus that deposits a film on one side of a glass substrate (hereinafter referred to as "substrate Sg") of a specified size having a rectangular outline by sputtering in a downward deposition manner. Hereinafter, the X-axis and Y-axis directions, which are orthogonal to each other on the upper surface of the stage body (mentioned later), will be defined as the X-axis direction and Y-axis direction, and the stage body will move up and down along the Z-axis direction, which is orthogonal to the X-axis and Y-axis directions. The terminology indicating direction is based on the arrangement posture of the magnetron sputtering apparatus shown. Figure 1 Based on.

[0016] Reference Figure 1 The magnetron sputtering apparatus SM of this embodiment includes a vacuum chamber 1. An exhaust port 11 is provided on the side wall of the vacuum chamber 1. The exhaust port 11 is connected to a vacuum pump 13, such as a rotary pump or a cryogenic pump, via an exhaust pipe 12, thereby exhausting the vacuum in the vacuum chamber 1 to a specified pressure. A gas inlet 14 is also provided on the side wall of the vacuum chamber 1 for introducing sputtering gas composed of rare gases such as argon (and sometimes reactive gases such as oxygen). The gas inlet 14 is connected to a gas source outside the figure via a gas inlet pipe 16 equipped with a mass flow controller 15, allowing the sputtering gas with controlled flow to be introduced into the film formation space 1a between the target and the substrate. Furthermore, the cathode unit Uc is detachably mounted on the upper wall of the vacuum chamber 1.

[0017] The cathode unit Uc includes: a single target 2, the outline of which corresponds to the substrate Sg, and the area of ​​which is slightly larger than that of the substrate Sg; and a plurality of (six in this embodiment) magnet units 3, which are arranged above the target 2 (located outside the vacuum chamber 1, on the side of the target 2 facing away from the sputtering surface 21), and are arranged side by side at equal intervals in the X-axis direction. The target 2 is selected according to the composition of the thin film to be formed on the surface of the substrate Sg, and is manufactured in a generally rectangular cuboid shape when viewed from above using known methods. The magnetron sputtering apparatus SM of this embodiment can form thin films such as aluminum films, titanium films, tungsten films, and molybdenum films simply by replacing the target 2. The back plate 22 is bonded to the upper surface of the target 2, and the coolant can circulate in the back plate 22 to cool the target 2 during sputtering. Then, the target 2 spacer insulating plate 23 is mounted on the upper part of the vacuum chamber 1 with its sputtering surface 21 facing the inside of the vacuum chamber 1 and facing the substrate Sg. The target 2 is connected to the output terminal 24a of the sputtering power supply 24 through the back plate 22, and a DC power supply with a negative potential or a pulsed DC power supply can be applied to the target 2. Furthermore, a frame-shaped ground potential shielding plate 4 is installed in the vacuum chamber 1, which is mainly used to prevent coating on the part of the back plate 22 extending outward from the outer edge of the target 2. During sputtering, the shielding plate 4 acts as an anode.

[0018] Each magnet unit 3 has the same shape and a support plate (yoke) 31 made of magnetic material with its long side in the Y-axis direction, which is approximately parallel to the unused sputtering surface 21 of the target 2. On the lower surface of the support plate 31, central magnets 32 are arranged in a straight line at their center, and peripheral magnets 33 are arranged along the outer periphery of the support plate 31 with spacing around the central magnets 32. The magnet units 3 are arranged side by side such that the central magnets 32 of each magnet unit 3 are spaced apart in the X-axis direction with an orientation consistent with the Y-axis direction, and the distance between the sputtering surface 21 and the magnet units 3 is at a predetermined interval. The volume of the central magnet 32 ​​when converted to the same magnetization intensity is designed to be equal to the sum of the volumes of each peripheral magnet 33 when converted to the same magnetization intensity. A closed-loop leakage magnetic field (not shown) balanced with the film deposition space 1a is activated, such that a line passing through a position where the vertical component of the magnetic field is zero extends along the extension direction of the central magnet 32 ​​and closes into a racetrack shape. Each magnet unit 3 is connected to the drive shaft 51 of a drive device 5 such as a motor or cylinder, and they reciprocate together with a predetermined stroke value. Furthermore, the substrate stage ST of this embodiment is arranged inside the vacuum chamber 1, facing the target 2.

[0019] The substrate stand ST has a metal stand body 6, and the substrates Sg are arranged on the upper surface of the stand body 6 with their opposite edges aligned with the X-axis and Y-axis directions, respectively. A drive shaft 61, which penetrates the lower wall of the vacuum chamber 1 and protrudes into the vacuum chamber 1 while maintaining airtightness, is connected to the lower surface of the stand body 6. Furthermore, the stand body 6 can be moved up and down by the drive shaft 61 via a drive source 62 such as a cylinder or linear motor located outside the vacuum chamber 1. Thus, the stand body 6 can be positioned at a substrate junction point away from the target 2 where substrates Sg are joined, and at a substrate processing point near the target 2 where film deposition is performed (…). Figure 1 The platform body 6 is formed with multiple through holes 63 extending vertically. The diameter of each through hole 63 and the distance between each through hole 63 are appropriately set considering the substrate size and the configuration of the heater 7 mentioned later. Support rods 64 are inserted into each through hole 63 with gaps. Each support rod 64 is made of a metal rod with high mechanical strength and has: a large diameter portion 64a that is spaced out and housed in the through hole 63 at the substrate processing position; and a small diameter portion 64b that extends continuously downward from the large diameter portion 64a. Furthermore, a cap 64c made of a different material is mounted on the upper end of each support rod 64. The cap 64c is, for example, a molded body made of a resin molding material such as polyimide. Although not specifically illustrated, an upwardly extending mounting hole is formed on the lower surface of the cap 64c, and the cap 64c is installed by inserting it from above into another small diameter portion formed on the upper end of each support rod 64.

[0020] Guide members 65 are vertically mounted on the frame body 6, surrounding the lower edge of each through hole 63. Each guide member 65 has a cylindrical member 65b of a predetermined length, made of a metal with high mechanical strength, and has a through hole 65a through which the small-diameter portion 64b of each support rod 64 passes. The upper surface of the cylindrical member 65b is provided with an upwardly extending cylindrical protrusion 65c surrounding the upper edge of the through hole 65a, which is fitted into the through hole 63 from below. Thus, when the frame body 6 moves upward relative to each support rod 64, the lower surface of the large-diameter portion 64a of each support rod 64 abuts against the upper surface of the protrusion 65c, thereby locking each support rod 64 (restricting downward movement of each support rod 64) and preventing each support rod 64 from falling out of the through hole 63. Furthermore, the length of the large-diameter portion 64a of each support rod 64 is appropriately set considering the amount of protrusion of each support rod 64 from the platform body 6 at the substrate junction and the thickness of the platform body 6. Also, the diameters of the large-diameter portion 64a and the small-diameter portion 64b are set considering the diameters of the through hole 63 and the through hole 65a. In addition, a pair of upper and lower guide rollers 66 are provided on the cylindrical member 65b to guide the relative vertical movement of each support rod 64 (its small-diameter portion 64b).

[0021] A support plate 67 is provided on the inner surface of the lower wall of the vacuum chamber 1, and a limiting platform 68 is provided on the upper surface of the support plate 67. The limiting platform 68 is abutted against by the lower end face of each support rod 64 and restricts the downward movement of each support rod 64. The limiting platform 68 also functions as a stop member. Alternatively, the support plate 67 may be omitted, and the limiting platform 68 may be directly provided on the inner surface of the lower wall of the vacuum chamber 1. Furthermore, spacer members (not shown) may be detachably provided on the upper or lower surface of the limiting platform 68 to appropriately change the amount of protrusion of each support rod 64 from the main body 6 at the substrate junction. In addition, a heater 7 is assembled on the main body 6 to control the substrate Sg at a specified temperature during the sputtering film deposition process. Although not specifically illustrated and described in detail, the heater 7 is composed of a known sheathed heater in which a heating element such as a nickel-chromium wire that heats up by means of electricity is assembled inside a metal tube, and is powered by a known power source.

[0022] Also refer to Figure 2 The upper surface of the platform body 6 is divided into a central region Cz (a rectangle with its longer side in the X-axis direction) surrounding a center and a peripheral region Sz surrounding the central region Cz. The central region Cz is further divided into a main region Cz1 and two sub-regions Cz2, which are located on both sides of the main region Cz1 in the X-axis direction and have a smaller area than the main region Cz1. On the other hand, the peripheral region Sz has: a first peripheral region Sz1 (a rectangle with its longer side in the X-axis direction) located on both sides of the central region Cz in the Y-axis direction; and a second peripheral region Sz2 (a rectangle with its longer side in the Y-axis direction) located on both sides of the central region Cz in the X-axis direction. In this embodiment, the second peripheral regions Sz2 extend to both ends of the platform body 6 in the Y-axis direction, and the first peripheral region Sz1 is located between the two ends of the second peripheral region Sz2 in the Y-axis direction, such that the four corners of the platform body 6 are substantially part of the second peripheral region Sz2, but this is not a limitation. Furthermore, with the substrate Sg positioned on the main body 6, the length of the first peripheral region Sz1 in the Y-axis direction is set such that its amplitude spans both sides of the substrate Sg extending along the X-axis direction, and the length of the second peripheral region Sz2 in the X-axis direction is set such that its amplitude spans both sides of the substrate Sg extending along the Y-axis direction. Furthermore, the areas of the central region Cz and the peripheral regions Sz (distance from the outer edge of the substrate Sg) are experimentally determined in advance based on the size of the substrate Sg, the temperature range during heating of the substrate Sg, and the temperature gradient to be applied. Typically, the main region Cz1, which is less susceptible to plasma influence during film deposition, is a large area. On the other hand, the areas of the first peripheral region Sz1 and the second peripheral region Sz2, which are susceptible to depressions and plasma influence during film deposition, are both smaller than the main region Cz1. Furthermore, the area of ​​the sub-region Cz2 is also smaller than the main region Cz1.

[0023] The following heaters are installed: a first heater 7a, a sheath heater 7 used to heat the main region Cz1 of the central region Cz; a second heater 7b, a sheath heater 7 used to heat the first peripheral region Sz1; a third heater 7c, a sheath heater 7 used to heat the second peripheral region Sz2; and a fourth heater 7d, a sheath heater 7 used to heat the sub-region Cz2 of the central region Cz. The type (material, etc.) and length of the first heaters 7a to the fourth heaters 7d are appropriately set according to the area of ​​the central region Cz and the peripheral region Sz, the heating temperature range (e.g., 50℃ to 200℃), and the applied temperature gradient (e.g., 50℃ to 100℃), and configured with a prescribed wiring pattern. Alternatively, the sheath heaters can be arranged relatively densely at both ends of the second peripheral region Sz2 in the Y-axis direction to efficiently heat the four corners of the platform body 6. When heating the substrate Sg, the output density (W / cm²) of the first heaters 7a to the fourth heaters 7d is adjusted. 2 The heat generation of the first peripheral region Sz1 is lower than that of the main region Cz1 of the central region Cz, and the heat generation of the second peripheral region Sz2 is lower than that of the first peripheral region Sz1. Furthermore, the heat generation of the sub-region Cz2 of the central region Cz is lower than that of the main region Cz1.

[0024] For example, based on the heating temperature of the substrate Sg (e.g., 150°C), and using the output density (W / cm²) of the first heater 7a as a reference, the output density of the second heater 7b is set to 1.1 to 1.75 times that of the first heater 7a, and the output density (W / cm²) of the third heater 7c is set to 1.1 to 2.0 times that of the first heater 7a. Furthermore, the output density (W / cm²) of the fourth heater 7d is set to 1.1 to 1.5 times that of the first heater 7a. On the other hand, in cases such as applying a predetermined temperature gradient, the output density (W / cm²) of the second heater 7b is set to at least 1.5 to 2.5 times that of the first heater 7a, based on the output density of the first heater 7a. In this case, the output density (W / cm²) of the third heater 7c is appropriately set according to the area of ​​the second peripheral region Sz2, and depending on the situation, the output density may be set to zero. The output density (W / cm²) of the fourth heater 7d is set to 2.0 to 4.5 times that of the first heater 7a. The film formation process on the substrate Sg will be described in detail below.

[0025] When forming a film on substrate Sg, with the substrate stand ST's main body 6 in the substrate junction position, the first heater 7a to the fourth heater 7d are energized by a power supply. Although not illustrated, at the substrate junction position, the lower surface of the small-diameter portion 64b of each support rod 64 abuts against the upper surface of the limiting stage 68, and each support rod 64 protrudes from the main body 6 by a predetermined amount. It is also possible that the large-diameter portion 64a of each support rod 64 protruding from the main body 6 may increase due to deflection caused by the weight of substrate Sg. Then, substrate Sg is transported by a transport robot through the substrate delivery outlet 17 (see reference) opened on the side wall of vacuum chamber 1. Figure 1 The substrate is temporarily received in the vacuum chamber 1, with the substrate supported by the upper surface of the support rod 64. After the substrate delivery outlet 17 is closed, the transfer robot is moved back, and when the vacuum chamber 1 is evacuated to the specified pressure, the main body 6 of the platform is moved upward relative to the support rod 64.

[0026] As the main body 6 of the platform moves upward, the small-diameter portion 64b of each support rod 64 is guided by a pair of upper and lower guide rollers 66 and moves downward relative to the main body 6 of the platform. When the lower surface of the large-diameter portion 64a of the support rod 64 abuts against the upper surface of the protrusion portion 65c and locks each support rod 64, the downward movement of each support rod 64 is restricted, and each support rod 64 is prevented from falling out of each through hole 63. In this state, the lower surface of the small-diameter portion 64b of each support rod 64 is away from the upper surface of the limiting platform 68, and the large-diameter portion 64a of each support rod 64, including the cover 64c, is completely submerged in the through hole 63 at the substrate processing position (see reference). Figure 1 At this point, the substrate Sg is positioned in contact with the upper surface of the stage body 6. In this state, the substrate Sg is heated to a specified temperature through contact heat conduction from the stage body 6.

[0027] When the substrate Sg is heated to a specified temperature (e.g., 150°C) with good uniformity throughout its entire surface, for example, the heat generation of the first peripheral region Sz1 is set to 30% to 50% of the heat generation of the main region Cz1 of the central region Cz, and the heat generation of the second peripheral region Sz2 is set to 80% to 99% of the heat generation of the first peripheral region Sz1. Furthermore, the heat generation of the sub-region Cz2 of the central region Cz is set to 10% to 30% of the heat generation of the main region Cz1. This confirms that even if the substrate Sg is a large-area substrate of G8.7 generation, it can be heated with good in-plane uniformity (e.g., within the range of 150°C ± 5°C). Therefore, it can be used to preheat the substrate Sg to a specified temperature when forming thin films such as aluminum or titanium films on the surface of the substrate Sg.

[0028] On the other hand, when heating is performed with a predetermined temperature gradient applied between the central portion and the outer periphery of the substrate Sg (especially at both ends in the X-axis direction), the heat generation of the first peripheral region Sz1 is set to a range of 30% to 50% of the heat generation of the main region Cz1 of the central region Cz, based on the heating temperature of the main region Cz1 of the central region Cz. Furthermore, the heat generation of the second peripheral region Sz2 is set to less than 10% of the heat generation of the first peripheral region Sz1 (it can be set to zero depending on the situation). In addition, the heat generation of the sub-region Cz2 of the central region Cz is set to a range of 60% to 80% of the heat generation of the main region Cz1 of the central region Cz. As a result, a temperature difference region in which the temperature decreases towards the edge of the substrate can be formed at the outer periphery of the substrate Sg, especially at both ends in the X-axis direction, confirming that the substrate Sg can be heated to a state where a predetermined temperature gradient is applied (for example, the temperature of the central portion of the substrate Sg is 200°C, and the temperature difference between the central portion and the two ends in the X-axis direction is, for example, 100°C). Therefore, it can be used, for example, to form a tungsten or molybdenum film (i.e., a film whose crystal structure is easily affected by the substrate temperature during film formation) on the surface of a substrate Sg, taking into account the local heat input caused by plasma, and to heat the substrate Sg under a specified temperature gradient. Furthermore, after the substrate Sg is heated to the specified temperature, each target 2 is sputtered in a vacuum chamber 1 under a vacuum atmosphere, thereby forming a film on the upper surface of the substrate Sg. After film formation, the stage body 6 is moved downwards from the substrate processing position to the substrate junction position.

[0029] By adopting the above-described embodiments, it is possible to simultaneously heat a large-area substrate Sg with a rectangular profile to a specified temperature with good in-plane uniformity according to the target type, and to set a predetermined temperature gradient between the central region and the outer periphery of the substrate Sg. A variety of thin films with good film uniformity can be formed by a single magnetron sputtering system SM (that is, even when forming tungsten films or molybdenum films, the film can be formed with good in-plane uniformity).

[0030] To confirm the effectiveness of the present invention, the following experiments were conducted using the aforementioned magnetron sputtering apparatus SM. A G8.7 generation glass substrate was used as the substrate Sg, positioned on the upper surface of the stage body 6, and heated in a vacuum chamber 1 under a vacuum atmosphere. In the first experiment, based on the heat generation of the main region Cz1 of the central region Cz, the heat generation of the first peripheral region Sz1 was set to 40% of that of the main region Cz1, the heat generation of the second peripheral region Sz2 was set to 80% of that of the first peripheral region Sz1, and the heat generation of the sub-region Cz2 of the central region Cz was set to 20% of that of the main region Cz1. The center temperature of the substrate was heated to 150°C. Thus, although not illustrated, it can be confirmed that the temperature at both ends of the substrate Sg in the X-axis direction is lower, but the substrate surface is heated approximately uniformly within a range of ±5°C.

[0031] In the second experiment, using the heat generation of the main region Cz1 of the central region Cz as a benchmark, the heat generation of the first peripheral region Sz1 was set to 40% of that of the main region Cz1, the heat generation of the second peripheral region Sz2 was set to 0% of that of the first peripheral region Sz1, and the heat generation of the sub-region Cz2 of the central region Cz was set to 70% of that of the main region Cz1. Then, the central portion Sg1 of the substrate Sg was heated to 200°C, and the results were as follows. Figure 3 As shown, the central portion Sg1 of the substrate Sg, corresponding to the central region Cz of the main body 6, is heated to approximately 200°C, while the portions Sg2 at both ends of the substrate Sg in the Y-axis direction, corresponding to the first peripheral region Sz1, are heated to approximately 180°C. Furthermore, in the portions Sg3-Sg5 on both sides of the substrate Sg in the X-axis direction, corresponding to the second peripheral region Sz2, the temperature decreases towards the substrate ends in the X-axis direction, with portion Sg5 being heated to 100°C higher than the central portion Sg1. This confirms that portions Sg3 to Sg5 on both sides of the X-axis direction form a temperature difference zone, allowing a predetermined temperature gradient to be applied.

[0032] In the third experiment, a 250 nm thick molybdenum film was formed on the glass substrate heated in the second experiment, and the in-plane distribution of the film resistivity (Ω / □) was measured. As sputtering conditions, a molybdenum target of specified purity was used, the TS distance between the target 2 and the substrate Sg was set to 110 mm, and argon gas was introduced at 120 sccm to maintain the pressure in the vacuum chamber 1 at 0.2 Pa. Furthermore, a 200 kW DC power was applied to the target 2 from the sputtering power source 24, and sputtering was performed on the target 2. As a comparative experiment, the substrate was uniformly heated to 200°C over its entire surface, and a 250 nm thick molybdenum film was formed under the same conditions as above. It was observed that the in-plane distribution of the film thickness in the comparative experiment was approximately ±9%, and the in-plane distribution of the film resistivity was approximately ±17%. It was found that the resistivity was highest at the central part Sg1 of the substrate Sg, while the film resistivity was low at both ends of the substrate along the X-axis. In contrast, in the molybdenum film of the third experiment, as in the comparative experiment, the in-plane distribution of the film thickness was approximately ±9%, and the difference in the thin film resistance values ​​between the central part Sg1 of the substrate Sg and the two ends of the substrate Sg in the X-axis direction decreased, and it was confirmed that the in-plane distribution of the thin film resistance value was approximately ±10%.

[0033] The embodiments of the present invention have been described above, but various modifications can be made without departing from the inventive concept. In the above embodiments, the substrate stage ST and the magnetron sputtering apparatus SM equipped with the substrate stage ST were described as examples of film formation by downward deposition, but the invention is not limited to this and can be widely applied to apparatuses employing so-called upward deposition or side deposition methods. Furthermore, in the above embodiments, the film quality was described using the thin-film resistivity value as an example, but the substrate stage of the present invention can also be used to apply a predetermined temperature gradient to the substrate, for example, to control the stress of the thin film. In addition, in the above embodiments, a sheathed heater was used as an example of heater 7, but the invention is not limited to this; other known heating devices can be used, as long as the heat generation of the central region Cz and the peripheral region Sz can be set to predetermined values.

[0034] Explanation of reference numerals in the attached figures SM. Magnetron sputtering apparatus, ST. Substrate stand, Sg. Substrate (glass substrate), 1. Vacuum chamber, 2. Target, 3. Magnet unit, 4. Shielding plate (anode plate), 5. Drive unit, 6. Stand body, 7. Heater, 7a. First heater (component of heater), 7b. Second heater (component of heater), 7c. Third heater (component of heater), 7d. Fourth heater (component of other heaters), Cz. Central region, Sz1. First peripheral region (peripheral region), Sz2. Second peripheral region (peripheral region).

Claims

1. A substrate stand, comprising: a stand body having a substrate with a rectangular outline disposed on its upper surface; and a heater mounted on the stand body to heat the substrate via heat conduction, characterized in that: Using the X-axis and Y-axis directions orthogonal to each other within the upper surface of the test bench as the X-axis and Y-axis directions respectively, the upper surface of the test bench is divided into a central region surrounding the center and a peripheral region surrounding the central region. The peripheral region has: a first peripheral region located on both sides of the central region along the Y-axis, with its width extending across both sides of the substrate provided on the upper surface of the test bench along the X-axis; and a second peripheral region located on both sides of the central region along the X-axis, with its width extending across both sides of the substrate provided on the upper surface of the test bench along the Y-axis. Heaters are provided in the divided central area, first peripheral area and second peripheral area. When each heater is working to heat the substrate, the heat generation in the first peripheral area is lower than that in the central area, and the heat generation in the second peripheral area is lower than that in the first peripheral area.

2. The substrate stand according to claim 1, characterized in that: The central region also has subdivided regions on both sides in the X-axis direction. When other heaters in each subdivided region also work to heat the substrate, the heat generated in the subdivided regions will be lower than that in the central region.

3. A magnetron sputtering apparatus comprising a substrate stage according to claim 1 or claim 2 located within a vacuum chamber, characterized in that: include: The target is configured facing the substrate disposed on the main body of the platform; and an anode plate with ground potential disposed around the target; the target is composed of a single target material larger than the outline of the substrate, and a plurality of magnet units are arranged side by side with spacing along the X-axis on the side of the target opposite to the sputtering surface; it also includes a driving device for causing each magnet unit to reciprocate synchronously along the X-axis. Based on the heat input to the substrate caused by plasma during the film formation process, the heat generation of the first peripheral region, the second peripheral region, and the subdivided region is adjusted according to the heat generation of the central region.

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