Sputtering device

Abstract

This sputtering device includes: a chamber; a substrate-holding part which is provided in the chamber and holds a substrate; a target-holding part which holds a target so as to face the substrate in the chamber; a position control part which controls the relative positional relationship between the substrate-holding part and the target-holding part in a first direction to a first position where the substrate and the target do not face each other and a second position where the substrate and the target face each other; and a shield which is located between the substrate and the target at the first position. The sputtering device generates plasma for the target at the first position.

Description

Sputtering Equipment

[0001] An embodiment of the present invention relates to a sputtering apparatus.

[0002] Display devices using liquid crystal or organic light-emitting diodes (OLEDs) have already been commercialized for small and medium-sized display devices such as smartphones. In particular, OLED display devices using OLEDs, which are self-emissive elements, have advantages over liquid crystal display devices, such as high contrast and no need for backlighting. However, because OLEDs are made of organic compounds, it is difficult to ensure high reliability of OLED display devices due to degradation of the organic compounds.

[0003] In recent years, development of so-called micro LED or mini LED displays, in which tiny LED chips are mounted within the pixels of a circuit board, has been progressing as next-generation display devices. LEDs are self-emitting elements similar to OLEDs; however, unlike OLEDs, LEDs are composed of stable inorganic compounds containing gallium (Ga) or indium (In). Therefore, compared to OLED display devices, micro LED display devices are more likely to ensure high reliability. Furthermore, LED chips have high luminous efficiency and can achieve high brightness. Therefore, micro LED or mini LED display devices are expected to be next-generation display devices with high reliability, high brightness, and high contrast.

[0004] Gallium nitride films used in micro LEDs and the like are generally formed on sapphire substrates using metal organic chemical vapor deposition (MOCVD) or hydride vapor phase epitaxy (HVPE) at high temperatures of 800° C. to 1000° C. However, in recent years, methods for forming gallium nitride films by sputtering, which allows film formation at relatively low temperatures, have been developed (see, for example, Patent Document 1).

[0005] JP 2012-119569 A

[0006] If the gallium nitride layer that constitutes the micro-LED could be deposited at low temperatures, it would be possible to form the micro-LED directly on a glass substrate. However, gallium nitride layers deposited using conventional sputtering equipment have problems with the crystallinity of the gallium nitride layer, making it difficult to achieve sufficient performance in micro-LEDs using the gallium nitride layer.

[0007] In view of the above problems, one object of one embodiment of the present invention is to provide a new sputtering apparatus.

[0008] A sputtering apparatus according to one embodiment of the present invention comprises a chamber, a substrate holder provided within the chamber for holding a substrate, a target holder for holding a target within the chamber so as to face the substrate, a position control unit for controlling the relative positional relationship between the substrate holder and the target holder in a first direction to a first position where the substrate and the target do not face each other, and a second position where the substrate and the target face each other, and a shield located between the substrate and the target at the first position, and generates plasma on the target at the first position.

[0009] A sputtering apparatus according to one embodiment of the present invention comprises a chamber, a substrate holder provided within the chamber for holding a substrate, a target holder for holding a target within the chamber so as to face the substrate, a magnet, and a position control unit for controlling the relative positional relationship between the substrate holder and the target holder in a first direction between a first position where the substrate and the target do not face each other and a second position where the substrate and the target face each other, wherein the target is configured to be located between the substrate and the magnet at the second position, and the orientation of the magnet is controlled so that, when a direction extending from an arbitrary point on the magnet to a surface of the substrate at the second position is defined as a third direction, the angle between the direction of plasma generated at the target and the third direction, with the magnet as the reference, at the first position is larger than the angle between the direction of plasma and the third direction, with the magnet as the reference at the second position.

[0010] A sputtering apparatus according to one embodiment of the present invention comprises a chamber, a substrate holding section provided within the chamber for holding a substrate, a target holding section for holding a target so as to face the substrate within the chamber, and a position control section for controlling the relative positional relationship between the substrate holding section and the target holding section in a first direction to a first position where the substrate and the target do not face each other, and a second position where the substrate and the target face each other, wherein at the second position, the substrate holding section is located in a third direction of the target holding section, and plasma is generated at the target in a state where the position of the substrate at the first position has been moved in the third direction from the position of the substrate at the second position.

[0011] FIG. 1 is a top view showing an overview of a sputtering apparatus according to an embodiment of the present invention. FIG. 2 is a top view showing an overview of a sputtering apparatus according to an embodiment of the present invention. FIG. 3 is a top view showing an overview of a sputtering apparatus according to an embodiment of the present invention. FIG. 4 is a top view showing an overview of a sputtering apparatus according to an embodiment of the present invention. FIG. 5 is a top view showing an overview of a sputtering apparatus according to an embodiment of the present invention. FIG. 6 is a top view showing an overview of a sputtering apparatus according to an embodiment of the present invention. FIG. 7 is a top view showing an overview of a sputtering apparatus according to an embodiment of the present invention. FIG. 8 is a top view showing an overview of a sputtering apparatus according to an embodiment of the present invention. FIG. 9 is a top view showing an overview of a sputtering apparatus according to an embodiment of the present invention.

[0012] Each embodiment of the present invention will be described below with reference to the drawings. The following disclosure is merely an example. Configurations that a person skilled in the art can easily arrive at by appropriately modifying the configuration of the embodiment while maintaining the gist of the invention are naturally included within the scope of the present invention. For clarity of explanation, the width, thickness, shape, etc. of each part in the drawings may be shown schematically compared to the actual form. However, the illustrated shapes are merely examples and do not limit the interpretation of the present invention. In this specification and each drawing, elements similar to those described above with reference to the previous drawings may be given the same reference numerals, and detailed descriptions may be omitted as appropriate.

[0013] In each embodiment of the present invention, the direction from the first member to the second member is referred to as "up" or "upper." Conversely, the direction from the second member to the first member is referred to as "down" or "downward." For convenience of explanation, the terms "up" and "downward" are used in the description. However, for example, the vertical relationship between the first member and the second member may be reversed from that illustrated. In the following description, for example, the expression "second member above the first member" merely describes the vertical relationship between the first member and the second member as described above, and other members may be disposed between the first member and the second member. "Above" or "below" refers to the stacking order in a structure in which multiple layers are stacked. When referring to a second member above a first member, the first member and the second member may not overlap in a planar view. On the other hand, when referring to a second member vertically above a first member, the first member and the second member may overlap in a planar view.

[0014] In this specification, unless otherwise specified, expressions such as "α includes A, B, or C," "α includes any of A, B, and C," and "α includes one selected from the group consisting of A, B, and C" do not exclude cases where α includes multiple combinations of A to C. Furthermore, these expressions do not exclude cases where α includes other elements.

[0015] The following embodiments can be combined with each other unless a technical contradiction occurs.

[0016] 1. First Embodiment A sputtering apparatus 10 according to one embodiment of the present invention and a sputtering method using the sputtering apparatus 10 will be described with reference to FIGS.

[0017] [1-1. Configuration of Sputtering Apparatus] FIG. 1 is a top view showing an overview of a sputtering apparatus according to one embodiment of the present invention. As shown in FIG. 1, the sputtering apparatus 10 includes a chamber 100, a target unit 200, a substrate holding unit 300, a shield 400, a control unit 600, a position control unit 610, a movement mechanism 620, and a holding mechanism 630. FIG. 1 shows only a portion of the chamber 100. The chamber 100 forms a closed space. The target unit 200, the substrate holding unit 300, the shield 400, the position control unit 610, the movement mechanism 620, and the holding mechanism 630 are provided within the chamber 100. Although not shown, the chamber 100 is provided with an exhaust port and a process gas supply port. The pressure inside the chamber 100 can be reduced via the exhaust port. Gases such as argon and nitrogen required for sputtering can be supplied into the chamber 100 via the process gas supply port.

[0018] A substrate 310, which is an object to be film-formed, is held by the substrate holding unit 300. In the example of FIG. 1 , the substrate 310 is held by the substrate holding unit 300 so that its main surface (film-forming surface) extends in the X-axis and Z-axis directions. In other words, the substrate 310 is held by the substrate holding unit 300 in a vertical position. The X-axis direction may be referred to as the "first direction." The positive Y-axis direction (the direction in which the arrow points) may be referred to as the "second direction." The positive Y-axis direction may be referred to as the Y-axis direction. The negative Y-axis direction (the direction opposite to the direction in which the arrow points) may be referred to as the "third direction." In the present embodiment, as described above, a configuration in which the substrate 310 is arranged so that its main surface extends in the X-axis and Z-axis directions has been exemplified, but this configuration is not limiting. The target unit 200 and the substrate 310 may be arranged so that the main surface extends in the X-axis and Y-axis directions.

[0019] The shield 400 is provided on the target unit 200 side of the substrate holding unit 300. In other words, the shield 400 is provided on the underside of the substrate holding unit 300. The shield 400 protrudes from the underside of the substrate holding unit 300 in the direction in which the target unit 200 is provided. In other words, the shield 400 protrudes from the substrate holding unit 300 in the Y-axis direction (second direction). In the Y-axis direction (second direction), a distance d1 from the underside (first surface) of the substrate holding unit 300 to the tip of the shield 400 is smaller than a distance d2 from the underside (first surface) of the substrate holding unit 300 to the target unit 200. Depending on the magnitude relationship between the distances d1 and d2, interference between the target unit 200 moving in the X-axis direction and the shield 400 can be avoided.

[0020] The surface unevenness of the shield 400 is greater than the surface unevenness of the substrate holding unit 300. If an adhesion prevention plate is provided on the shield 400, the surface unevenness of the adhesion prevention plate is greater than the surface unevenness of the substrate holding unit 300. With the above configuration, it is possible to prevent a film sputtered from the target unit 200 and attached to the shield 400 or the like from peeling off from the shield 400 or the like. As a result, it is possible to reduce particles (dust) in the film formed on the substrate 310.

[0021] The target unit 200 is disposed opposite the substrate holding unit 300. In other words, at a position during film formation (a second position described below), the target unit 200 is located in the Y-axis direction (second direction) of the substrate 310. The target unit 200 includes a target 210, a backing plate 220, a central magnet 240, a peripheral magnet 250, and a yoke 260. These components are shaped such that their elongated sides extend in the Z-axis direction. Although details are omitted, the target 210 is a flat target that extends in the Z-axis direction.

[0022] The backing plate 220 and the holding mechanism 630 may be referred to as a “target holding unit.” In this case, the target holding unit may be said to be provided in the chamber 100 and to hold the target 210.

[0023] The target 210 is made of a material having the same composition as the thin film to be formed on the deposition surface of the substrate 310, or containing elements contained in the thin film. For example, when a gallium nitride (GaN) thin film is formed on the deposition surface, the target 210 is made of GaN or gallium (Ga). In the target unit 200, the side facing the substrate holding unit 300 is referred to as the front side, and the side opposite the front side is referred to as the back side. The target 210 is fixed to the front side of the backing plate 220 by, for example, indium or the like.

[0024] A yoke 260 is fixed on the holding mechanism 630. The central magnet 240 and the peripheral magnets 250 are fixed to the front surface of the yoke 260. When the central magnet 240 and the peripheral magnets 250 are not particularly distinguished from each other, they may be simply referred to as "magnets." The central magnet 240 has a polarity opposite to that of the peripheral magnets 250. That is, these magnets form a magnetic field on the front side of the target 210 from the central magnet 240 toward the peripheral magnets 250 (or vice versa). These magnets confine electrons in the plasma, forming a highly concentrated plasma region on the front side of the target 210. In this plasma region, a process gas is ionized. For example, argon is used as the process gas. The ionized argon is accelerated toward the target 210 in a sheath region formed between the plasma region and the target 210. The accelerated argon ions collide with the target 210, sputtering the target material.

[0025] In addition to the above-mentioned GaN and Ga, materials such as aluminum, aluminum nitride, indium, indium nitride, or mixed crystals thereof may be used as the target 210. Materials obtained by doping impurities (dopants) into the above-mentioned materials may also be used as the target 210. For example, materials obtained by doping magnesium or silicon into gallium nitride may also be used. Gallium nitride containing magnesium as a dopant functions as a P-type semiconductor. Gallium nitride containing silicon as a dopant functions as an N-type semiconductor.

[0026] The holding mechanism 630 is connected to the moving mechanism 620. The moving mechanism 620 controls the positions of the holding mechanism 630 and the target unit 200 in the X-axis direction. A rail mechanism, for example, is used as the moving mechanism 620. However, other mechanisms may be used as the moving mechanism 620. The moving mechanism 620 is controlled by a position control unit 610. The position control unit 610 detects the positions in the X-axis direction of the holding mechanism 630 and the target unit 200 moved by the moving mechanism 620. A rotary encoder, for example, is used as the position control unit 610.

[0027] The position control unit 610 is connected to the control unit 600. The position control unit 610 controls the moving mechanism 620 based on a control signal from the control unit 600, thereby determining the positions of the holding mechanism 630 and the target unit 200 in the X-axis direction. Furthermore, the control unit 600 obtains current position information of the holding mechanism 630 and the target unit 200 in the X-axis direction from the position control unit 610.

[0028] In this embodiment, the position of the substrate holding unit 300 is fixed in the X-axis direction, and the position of the target unit 200 moves. The movement of the target unit 200 in the X-axis direction may be a swing (reciprocating or repeating in the positive and negative directions on the X-axis) or a unidirectional passage (in the positive and negative directions on the X-axis). However, the position of the target unit 200 may be fixed in the X-axis direction, and the position of the substrate holding unit 300 may move, or both the target unit 200 and the substrate holding unit 300 may move as described above. In other words, the position control unit 610 controls the relative positional relationship between the substrate holding unit 300 and the target unit 200 in the X-axis direction. The X-axis direction may be referred to as the "first direction."

[0029] The position of the target unit 200 shown in FIG. 1 is a position where no film is formed on the substrate 310. This position may be referred to as the "first position." At the first position, the substrate 310 and the target 210 do not face each other. On the other hand, when film formation is performed on the substrate 310, the position control unit 610 moves the target 210 to a position where the substrate 310 and the target 210 face each other. This position may be referred to as the "second position." At the second position, the substrate 310 and the target 210 face each other.

[0030] As shown in FIG. 1 , when the positional relationship between the target 210 and the substrate 310 is in the first position, the shield 400 is sandwiched between the target 210 and the substrate 310. The shield 400 may shield the region sandwiched between the target 210 and the substrate 310. A high-concentration plasma region generated around the target 210 is formed in a direction perpendicular to the surface of the target 210. Therefore, most sputtering particles fly in the perpendicular direction, but some sputtering particles fly in a direction oblique to the perpendicular direction (i.e., in FIG. 1 , the direction in which the substrate 310 is provided relative to the target 210). However, with the above configuration, sputtering particles flying from the surface of the target 210 in the direction of the substrate 310 are blocked by the shield 400 and do not reach the target 210.

[0031] [1-2. Sputtering Method] When sputtering is performed using the sputtering apparatus 10, the substrate 310 is held by the substrate holder 300, a process gas is introduced into the chamber 100, power is supplied to the electrodes (anode and cathode), and a plasma region is formed, thereby performing sputtering. In this case, when generating plasma by supplying power, plasma can be generated stably by using only argon gas as the process gas, or by using a gas with a higher argon ratio than that used during film formation. The above conditions are referred to as "argon-rich conditions." On the other hand, the conditions used during film formation, i.e., the conditions under which a layer of the film quality required to form a semiconductor device is formed, are referred to as "normal conditions."

[0032] For example, when forming a GaN layer on the substrate 310, argon and nitrogen are used as process gases. However, forming a GaN layer using the above-mentioned argon-rich conditions fails to produce a highly crystalline GaN layer. Therefore, if plasma is generated using argon-rich conditions at a position where sputtering particles reach the substrate 310, a portion of the formed GaN layer will contain GaN layers with low crystallinity. Therefore, as described above, plasma is first generated using argon-rich conditions when the positional relationship between the target 210 and the substrate 310 is in the first position. Then, while maintaining the plasma generation state, the process gas is changed to the normal condition, and the movement mechanism 620 is moved in the positive direction of the X-axis, controlling the positional relationship to the second position. This allows a highly crystalline GaN layer to be formed over the entire substrate 310. In other words, the shield 400 prevents sputtering particles sputtered by the plasma generated under argon-rich conditions from being deposited on the substrate 310. When a GaN layer is grown under argon-rich conditions, the GaN layer contains insufficient nitrogen, resulting in a GaN layer with low crystallinity in which gallium oxide (GaOx) is partially formed. On the other hand, when a GaN layer is grown under normal conditions, the GaN layer contains sufficient nitrogen, resulting in a Ga to N ratio close to 1:1 and a GaN layer with high crystallinity.

[0033] In other words, the ratio of argon gas to nitrogen gas in the chamber 100 when plasma is generated on the target 210 at the first position is greater than the ratio of argon gas to nitrogen gas in the chamber 100 when plasma is generated on the target 210 at the second position. However, the conditions for generating plasma may be the same at both the first and second positions. For example, plasma may be generated under normal conditions at the first position.

[0034] As described above, while a film is being formed on the substrate 310, the moving mechanism 620 moves in the positive direction of the X-axis to the position shown in FIG. 2. The position of the moving mechanism 620 shown in FIG. 2 corresponds to the position obtained by inverting the position (first position) of the moving mechanism 620 shown in FIG. 1 on the X-axis. In other words, the position shown in FIG. 2 also corresponds to the first position. When the film formation method is a one-way passage, the plasma is extinguished after the moving mechanism 620 reaches the position shown in FIG. 2, and film formation ends. On the other hand, when the film formation method is an oscillation method, the moving mechanism 620 returns from the position shown in FIG. 2 to the position shown in FIG. 1 while plasma is generated. With this configuration, layers of similar film quality can be formed near the end of the substrate 310 in the negative direction and near the end of the substrate 310 in the positive direction in the X-axis direction.

[0035] Although this embodiment illustrates the case of forming a GaN layer, the configuration to which this embodiment can be applied is not limited to the formation of a GaN layer. This embodiment may also be applied when forming a layer containing other nitrides or compounds. Alternatively, this embodiment may be applied to the formation of a metal layer that is not a compound. When sputtering a metal layer, only argon is used as the process gas, and a metal target is used as the target 210. In this case, a natural oxide film often forms on the target surface. To prevent this natural oxide film from forming on the substrate 310, a metal layer with few impurities can be obtained by generating plasma at the first position as described above and then moving to the second position.

[0036] As described above, the sputtering apparatus 10 according to this embodiment can prevent particles sputtered during plasma generation from forming a film on the substrate 310, thereby forming a high-quality layer on the substrate 310. For example, when forming a GaN layer on the substrate 310, a GaN layer with high crystallinity can be obtained.

[0037] [1-3. First Modification of Sputtering Apparatus] A modification of this embodiment will be described with reference to Fig. 3. Fig. 3 is a top view showing an outline of a sputtering apparatus according to one embodiment of the present invention.

[0038] The sputtering apparatus 10 shown in FIG. 3 is similar to the sputtering apparatus 10 shown in FIG. 1 , but the position of the shield 400 is different. As shown in FIG. 3 , the shield 400 is provided on the substrate holding unit 300 side of the backing plate 220. In other words, the shield 400 is provided on the front surface of the backing plate 220. The shield 400 protrudes from the front surface of the backing plate 220 in the direction in which the substrate holding unit 300 is provided. The vertical distance d1 from the front surface of the backing plate 220 to the tip of the shield 400 is smaller than the vertical distance d2 from the front surface of the backing plate 220 to the underside of the substrate holding unit 300. Depending on the magnitude relationship between the distances d1 and d2, interference between the moving target unit 200 and the shield 400 can be avoided.

[0039] In this embodiment, since the substrate holding part 300 is provided below the substrate 310, the distance d2 is the distance from the front surface of the backing plate 220 to the bottom surface of the substrate holding part 300. However, if the substrate 310 is provided below the substrate holding part 300, the distance d2 is the distance from the front surface of the backing plate 220 to the bottom surface of the substrate 310.

[0040] 3 illustrates a configuration in which the shield 400 is provided on the backing plate 220, but the configuration is not limited to this. For example, the shield 400 may be provided on another member of the target unit 200. Alternatively, the shield 400 may be provided on the holding mechanism 630 or the like. In other words, the shield 400 may be provided on the target holding unit. In this embodiment, the backing plate 220 and the holding mechanism 630 are listed as examples of the target holding unit, but other members having the function of holding a target are also included in the target holding unit. It can be said that the shield 400 protrudes from the target holding unit in the negative direction of the Y axis (third direction).

[0041] The front surface of backing plate 220 and the upper surface of holding mechanism 630 may be referred to as the "second surface of the target holding unit." In this case, it can be said that the distance from the second surface of the target holding unit to the tip of shield 400 in the third direction is shorter than the distance from the second surface to substrate 310 or substrate holding unit 300 at the second position. In Modification 1, plasma is also generated using argon-rich conditions at the first position shown in FIG.

[0042] [1-4. Modification 2 of the Sputtering Apparatus] A modification of this embodiment will be described with reference to Figures 4 and 5. Figures 4 and 5 are top views showing an outline of a sputtering apparatus according to one embodiment of the present invention.

[0043] The sputtering apparatus 10 shown in Fig. 4 is similar to the sputtering apparatus 10 shown in Fig. 3, but differs from the sputtering apparatus 10 in that a second shield 410 is provided in addition to a first shield 400. As shown in Fig. 4, the sputtering apparatus 10 is provided with a first shield 400 and a second shield 410. The configuration of the first shield 400 is the same as the configuration of the shield 400 in Fig. 3, and therefore a description thereof will be omitted.

[0044] The second shield 410 is provided on the substrate holding part 300. The substrate holding part 300 is provided with a through-hole 320 that penetrates from the top surface to the bottom surface of the substrate holding part 300 in the Y-axis direction. The second shield 410 is provided so as to be able to slide up and down (second direction and third direction) inside the through-hole 320. The sliding movement of the second shield 410 in the up and down direction is controlled by, for example, the control part 600.

[0045] While FIG. 4 illustrates a configuration in which the first shield 400 is provided on the backing plate 220, the present invention is not limited to this configuration. For example, the first shield 400 may be provided on another component of the target unit 200. Alternatively, the first shield 400 may be provided on the holding mechanism 630 or the like. The backing plate 220 and the holding mechanism 630 may be collectively referred to as the "target holding unit." In this case, the target holding unit can be said to be provided in the chamber 100 and to hold the target 210. The first shield 400 can be said to protrude from the target holding unit in the negative direction of the Y axis (third direction). On the other hand, the second shield 410 can be said to protrude from the substrate holding unit 300 in the Y axis direction (second direction).

[0046] As shown in Fig. 4, when the second shield 410 has moved in the Y-axis direction, the lower end (end in the Y-axis direction) of the second shield 410 is located lower (in the Y-axis direction) than the upper end (end in the negative Y-axis direction) of the first shield 400. In other words, when viewed in the X-axis direction, the first shield 400 and the second shield 410 partially overlap each other. In the second modification, plasma is also generated using argon-rich conditions at the first position shown in Fig. 4.

[0047] As described above, while maintaining the plasma generation state, the process gas is changed to the normal condition, and the target unit 200 is moved from the first position to the second position. In this case, to avoid interference between the first shield 400 and the second shield 410, the second shield 410 slides upward as shown in Fig. 5. In the state shown in Fig. 5, the lower end of the second shield 410 is positioned above the upper end of the first shield 400.

[0048] In the second modification, a configuration in which the second shield 410 provided on the substrate holding part 300 slides up and down is exemplified, but the present invention is not limited to this configuration. For example, the first shield 400 provided on the backing plate 220 or the like may slide up and down.

[0049] [1-5. Modification 3 of the Sputtering Apparatus] A modification of this embodiment will be described with reference to Fig. 6. Fig. 6 is a top view showing an outline of a sputtering apparatus according to one embodiment of the present invention.

[0050] The sputtering apparatus 10 shown in FIG. 6 is similar to the sputtering apparatus 10 shown in FIG. 1 , but the position of the shield 400 is different. As shown in FIG. 6 , the shield 400 is provided so as to cover at least a portion of the side surface 301 of the substrate holding unit 300. Specifically, the shield 400 is inclined with respect to the Y-axis direction. The shield 400 is plate-shaped, and the target 210 is provided in a direction perpendicular to the surface of the shield 400. The shield 400 prevents sputtering particles sputtered from the target 210 from adhering to the lower surface 302 and side surface 301 of the substrate holding unit 300. The other configurations shown in FIG. 6 are the same as those shown in FIG. 1 , and therefore, description thereof will be omitted.

[0051] 6 illustrates an example in which the shield 400 is plate-shaped, but the present invention is not limited to this configuration. For example, the shield 400 may be bent along the lower surface 302 and side surface 301 of the substrate holding unit 300. In this case, the portion of the shield 400 that is provided along the lower surface 302 of the substrate holding unit 300 may be provided over the entire substrate holding unit 300, except for the portion where the substrate 310 is exposed. In the third modification, plasma is generated using argon-rich conditions at the first position shown in FIG.

[0052] The sputtering apparatus 10 according to the above-described modified example can also achieve the same effects as those of this embodiment.

[0053] 7 and 8, a sputtering apparatus 10A according to one embodiment of the present invention and a sputtering method using the sputtering apparatus 10A will be described. The configuration of the sputtering apparatus 10A shown in FIG. 7 is similar to the configuration of the sputtering apparatus 10 shown in FIG. 1, but differs from the sputtering apparatus 10 in that a member corresponding to the shield 400 in FIG. 1 is not provided. In the following description, a description of the same configuration as the sputtering apparatus 10 shown in FIG. 1 will be omitted, and differences from the sputtering apparatus 10 will be mainly described. In the following description, when describing a configuration similar to that of the first embodiment, reference will be made to FIGS. 1 and 2, and the alphabet "A" will be added after the reference numerals shown in these figures.

[0054] [2-1. Configuration of the Sputtering Apparatus] FIG. 7 is a top view showing an overview of a sputtering apparatus according to one embodiment of the present invention. As shown in FIG. 7, the sputtering apparatus 10A includes a chamber 100A, a substrate holder 300A provided within the chamber 100A and configured to hold a substrate 310A, a target 210A facing the substrate 310A within the chamber 100A, a magnet (a central magnet 240A or a peripheral magnet 250A), and a position controller 610A. The position controller 610A controls the relative positional relationship between the substrate holder 300A and the target 210A in the X-axis direction (first direction) between a first position where the substrate 310A and the target 210A do not face each other, and a second position where the substrate 310A and the target 210A face each other. At the second position, the target 210A is sandwiched between the substrate 310A and the magnet.

[0055] Neither the substrate holding unit 300A nor the backing plate 220A is provided with a member equivalent to the shield 400 shown in FIG. 1. On the other hand, in the sputtering apparatus 10A, a holding mechanism 630A is connected to a moving mechanism 620A via a connecting unit 640A. The holding mechanism 630A is rotatable about the connecting unit 640A. In other words, the target 210A is rotatable about the connecting unit 640A. The rotation direction of the holding mechanism 630A is controlled by a control unit 600A.

[0056] [2-2. Sputtering Method] When a sputtering process is performed using the sputtering apparatus 10A, as shown in FIG. 8, the perpendicular to the surface of the target 210A at the first position faces away from the substrate 310A. In this case, the magnet is also tilted in the same direction as the target 210A. Therefore, the direction in which plasma is generated relative to the target 210A is also tilted in the same direction. As shown in FIG. 7, when the perpendicular to the surface of the target 210A faces the negative direction of the Y axis (third direction), plasma is generated in the third direction relative to the magnet. On the other hand, as shown in FIG. 8, when the perpendicular to the surface of the target 210A is tilted at an angle θ with respect to the third direction, plasma is generated in a direction D tilted at an angle θ with respect to the third direction with respect to the magnet. θ is formed.

[0057] As shown in FIG. 8, the plasma flows in the direction D θ When the target 210A is formed in the direction D, the sputtering particles sputtered on the surface of the target 210A are θ 8 to the target 210A. Therefore, the sputtered particles hardly adhere to the substrate 310A. With the plasma generated, the orientation of the target 210A is controlled from the state shown in FIG. 8 to the state shown in FIG. 7, and the position of the target 210A is moved to the second position, thereby forming a film on the substrate 310A.

[0058] At the second position, which is the position during film formation, the direction in which a line extending from any point on the magnet (central magnet 240A or peripheral magnet 250A) perpendicular to the surface of substrate 310A extends is the third direction (negative direction of the Y axis). The orientation of the magnet is controlled so that the angle (angle θ) between the direction of plasma generated at target 210A and the third direction, with the magnet as a reference, at the first position is larger than the angle between the direction of plasma with the magnet as a reference at the second position and the third direction.

[0059] As described above, the sputtering apparatus 10A according to this embodiment can prevent particles sputtered during plasma generation from forming a film on the substrate 310A, thereby forming a high-quality layer on the substrate 310A. For example, when forming a GaN layer on the substrate 310A, a GaN layer with high crystallinity can be obtained.

[0060] 3. Third Embodiment A sputtering apparatus 10B according to one embodiment of the present invention and a sputtering method using the sputtering apparatus 10B will be described with reference to FIG. 9. The configuration of the sputtering apparatus 10B shown in FIG. 9 is similar to that of the sputtering apparatus 10A shown in FIG. 7, but the configuration of the movement mechanism 620B is different from that of the movement mechanism 620A. In the following description, the description of the configuration similar to that of the sputtering apparatus 10A shown in FIG. 7 will be omitted, and differences from the sputtering apparatus 10A will be mainly described. In the following description, when describing the configuration similar to that of the second embodiment, reference will be made to FIGS. 7 and 8, and the alphabet "B" will be added instead of the alphabet "A" suffixed to the reference numerals shown in these figures.

[0061] [3-1. Configuration of the Sputtering Apparatus] FIG. 9 is a top view showing an overview of a sputtering apparatus according to one embodiment of the present invention. As shown in FIG. 9, the sputtering apparatus 10B includes a chamber 100B, a substrate holding unit 300B provided within the chamber 100B for holding a substrate 310B, a target 210B facing the substrate 310B within the chamber 100B, and a position control unit 610B. The position control unit 610B controls the relative positional relationship between the substrate holding unit 300B and the target 210B in the X-axis direction (first direction) between a first position where the substrate 310B and the target 210B do not face each other, and a second position where the substrate 310B and the target 210B face each other. At the second position, the substrate 310B is positioned in the negative direction of the Y-axis (third direction) of the target 210B.

[0062] Neither the substrate holder 300B nor the backing plate 220B has a component corresponding to the shield 400 shown in FIG. 1 . Meanwhile, in the sputtering apparatus 10B, the configuration of the moving mechanism 620B differs from the configuration of the moving mechanism 620A shown in FIG. 7 . Specifically, the moving mechanism 620B is divided into a first region 621B and a second region 622B. In the first region 621B, the moving mechanism 620B extends in the X-axis direction so as to maintain a constant distance between the substrate 310B and the target 210B. In the second region 622B, the moving mechanism 620B extends in the third direction. The first region 621B corresponds to the first position described above, and the second region 622B corresponds to the second position described above. In other words, the moving mechanism 620B is bent in the third direction between the first region 621B and the second region 622B so that the position of the target 210B moves in the third direction at the first position. The holding mechanism 630B is connected to the moving mechanism 620B via a connecting portion 640B. The holding mechanism 630B may or may not be rotatable around the connecting portion 640B.

[0063] [3-2. Sputtering Method] When sputtering is performed using sputtering apparatus 10B, plasma is generated in a state where target 210B is moved in a third direction at a first position (first region 621B) as shown in Fig. 9. With plasma generated, target 210B is moved to a second position (second region 622B), whereby a film is formed on substrate 310B. On the other hand, when target 210B is moved in the third direction as shown in Fig. 9, sputtering particles sputtered on the surface of target 210B hardly adhere to substrate 310B.

[0064] In other words, the sputtering apparatus 10B generates plasma for the target 210B while the position of the substrate 310B at the first position (first region 621B) is moved in the third direction from the position of the substrate 310B at the second position (second region 622B).

[0065] As in FIG. 8, the orientation of the target 210B may be tilted at the first position in FIG.

[0066] As described above, the sputtering apparatus 10B according to this embodiment can prevent particles sputtered during plasma generation from forming a film on the substrate 310B, thereby forming a high-quality layer on the substrate 310B. For example, when forming a GaN layer on the substrate 310B, a GaN layer with high crystallinity can be obtained.

[0067] 4. Fourth Embodiment A sputtering apparatus 10C according to one embodiment of the present invention and a sputtering method using the sputtering apparatus 10C will be described with reference to FIG. 10. The configuration of the sputtering apparatus 10C shown in FIG. 10 is similar to that of the sputtering apparatus 10 shown in FIG. 1, but differs from the sputtering apparatus 10 in that a member corresponding to the shield 400 in FIG. 1 is provided in a holding mechanism 630C. In the following description, a description of the same configuration as the sputtering apparatus 10 shown in FIG. 1 will be omitted, and differences from the sputtering apparatus 10 will be mainly described. In the following description, when describing a configuration similar to that of the first embodiment, reference will be made to FIGS. 1 and 2, and the letter "C" will be added after the reference numerals shown in these figures.

[0068] [4-1. Configuration of the Sputtering Apparatus] FIG. 10 is a top view showing an overview of a sputtering apparatus according to one embodiment of the present invention. As shown in FIG. 10, the sputtering apparatus 10C has a holding mechanism 630C provided with a movable shield 430C. The shield 430C includes a support 431C and a shielding portion 432C. The support 431C is rotatably connected to the holding mechanism 630C at a connection portion 433C. The shielding portion 432C is rotatably connected to the support 431C at a connection portion 434C. The shielding portion 432C has a shape that is bent in the Y-axis direction (second direction) near the end of the surface of the target 210C. The shielding portion 432C covers the target 210C when the target 210C is viewed in the Y-axis direction.

[0069] The shield 430C covers the surface of the target 210C at the first position, and moves to a position at the second position where it does not overlap with the target 210C when the target 210C is viewed in the Y-axis direction (second direction). Therefore, the shield 430C is not limited to the configuration shown in FIG. 10 and can be realized in other modes.

[0070] [4-2. Sputtering Method] When a sputtering process is performed using the sputtering apparatus 10C, plasma is generated in the state shown in Fig. 10. With the plasma generated, the support 431C and the shielding portion 432C rotate around the connecting portions 433C and 434C, as shown in Fig. 11, so that the surface of the target 210C is exposed from the shield 430C. In this state, the target 210C moves to the second position, whereby a film is formed on the substrate 310C.

[0071] In the present embodiment, the configuration has been exemplified in which the support 431C and the shielding portion 432C rotate about the connecting portions 433C and 434C to switch between a state in which the shielding portion 432C covers the surface of the target 210C and a state in which it does not cover the surface of the target 210C, but the present invention is not limited to this configuration. For example, the above-described switching may be performed by sliding the shielding portion 432C in the X-axis direction.

[0072] As described above, the sputtering apparatus 10C according to this embodiment can prevent particles sputtered during plasma generation from forming a film on the substrate 310C, thereby forming a high-quality layer on the substrate 310C. For example, when forming a GaN layer on the substrate 310C, a GaN layer with high crystallinity can be obtained.

[0073] 12 and 13, a sputtering apparatus 10D according to one embodiment of the present invention and a sputtering method using the sputtering apparatus 10D will be described. The configuration of the sputtering apparatus 10D shown in FIG. 12 is similar to the configuration of the sputtering apparatus 10 shown in FIG. 1, but differs from the sputtering apparatus 10 in that a member corresponding to the shield 400 in FIG. 1 is not provided and the target has a cylindrical shape. In the following description, a description of the same configuration as the sputtering apparatus 10 shown in FIG. 1 will be omitted, and differences from the sputtering apparatus 10 will be mainly described.

[0074] 5-1. Configuration of the Sputtering Apparatus] Fig. 12 is a top view showing an overview of a sputtering apparatus according to one embodiment of the present invention. As shown in Fig. 12, a sputtering apparatus 10D is provided with a target unit 500D instead of the target unit 200 of Fig. 1. The target unit 500D includes a support member 510D, a fixing member 511D, a yoke 512D, a central magnet 513D, a peripheral magnet 514D, a backing tube 515D, a target 516D, and a shield 517D. These components are shaped such that their longitudinal axis is in the Z-axis direction.

[0075] The support member 510D is rotatably fixed to the chamber 100D. The fixed member 511D is connected to the support member 510D and extends from the support member 510D toward the backing tube 515D. A yoke 512D is fixed to the end of the fixed member 511D. The central magnet 513D and peripheral magnets 514D are fixed to the yoke 512D and extend from the yoke 512D toward the backing tube 515D. The ends of the central magnet 513D and peripheral magnet 514D on the backing tube 515D side have a curved shape that follows the inner wall of the backing tube 515D.

[0076] The central magnet 513D and the peripheral magnets 514D have a linear shape extending in the Z-axis direction. The central magnet 513D and the peripheral magnets 514D rotate along the inner wall of the backing tube 515D around the support member 510D. The support member 510D is fixed to a fixing member 511D and rotates together with the central magnet 513D and the peripheral magnets 514D. However, the support member 510D may be fixed without rotating relative to the chamber 100D. In this case, the fixing member 511D is rotatably connected to the support member 510D.

[0077] The target 516D is fixed to the backing tube 515D. The backing tube 515D and the target 516D have a cylindrical shape centered on an axis extending in the Z-axis direction, and rotate around the support member 510D. The target 516D rotates independently of the central magnet 513D and the peripheral magnets 514D. When there is no particular distinction between the central magnet 513D and the peripheral magnets 514D, they may be simply referred to as "magnets."

[0078] The central magnet 513D has a polarity opposite to that of the peripheral magnets 514D. That is, these magnets form a magnetic field outside the target 516D that flows from the central magnet 513D toward the peripheral magnets 514D (or vice versa). This magnetic field confines electrons in the plasma, forming a highly concentrated plasma region in the region corresponding to the area between the central magnet 513D and the peripheral magnets 514D. In the plasma region, argon introduced as a process gas is ionized. The ionized argon is accelerated toward the target 516D in a sheath region formed between the plasma region and the target 516D. The accelerated argon ions collide with the target 516D, sputtering the target material.

[0079] The shield 517D has an opening and is shaped to cover the target 516D in areas other than the opening. The shield 517D is rotatable around the support member 510D. In other words, the rotation of the shield 517D regulates the direction of sputtering particles flying off the target 516D.

[0080] 13 , when a sputtering process is performed using the sputtering apparatus 10D, plasma is generated in the first position with the opening of the shield 517D and the magnets (central magnet 513D and peripheral magnet 514D) facing away from the substrate 310D. In this state, the target 516D rotates around the support member 510D, thereby cleaning the surface of the target 516D (pre-sputtering). In this state, because the opening and magnets of the shield 517D face away from the substrate 310D, almost no sputtering particles adhere to the substrate 310D.

[0081] When the pre-sputtering is completed, the shield 517D and the magnet are controlled to the orientation shown in FIG. 12, and in this state are moved to the second position, whereby film deposition is performed on the substrate 310D.

[0082] As described above, the sputtering apparatus 10D according to this embodiment can prevent particles sputtered during plasma generation from forming a film on the substrate 310D, thereby forming a high-quality layer on the substrate 310D. For example, when forming a GaN layer on the substrate 310D, a GaN layer with high crystallinity can be obtained.

[0083] The above-described embodiments of the present invention can be combined as appropriate as long as they are not mutually inconsistent. A product in which a person skilled in the art appropriately adds or deletes components or modifies designs, or adds or omits steps or modifies conditions, based on each embodiment, is also included within the scope of the present invention as long as it includes the gist of the present invention.

[0084] Even if there are other effects and advantages different from those brought about by the aspects of each of the above-mentioned embodiments, those that are clear from the description in this specification or that can be easily predicted by a person skilled in the art are naturally understood to be brought about by the present invention.

[0085] 10: Sputtering apparatus, 100: Chamber, 200: Target section, 210: Target, 220: Backing plate, 240: Central magnet, 250: Peripheral magnet, 260: Yoke, 300: Substrate holder, 301: Side, 302: Underside, 310: Substrate, 320: Through hole, 400, 410, 430C: Shield, 431C: Support, 432C: Shielding section, 433C, 434C: Connection section, 500D: Target section, 510D: Support member, 511D: Fixing member, 512D: Yoke, 513D: Central magnet, 514D: Peripheral magnet, 515D: Backing tube, 516D: Target, 517D: Shield, 600: Control section, 610: Position control section, 620: moving mechanism, 621B: first region, 622B: second region, 630: holding mechanism, 640A: connecting portion

Claims

1. A sputtering apparatus comprising: a chamber; a substrate holder provided within the chamber for holding a substrate; a target holder for holding a target within the chamber so as to face the substrate; a position control unit for controlling the relative positional relationship between the substrate holder and the target holder in a first direction to a first position where the substrate and the target do not face each other, and a second position where the substrate and the target face each other; and a shield located between the substrate and the target at the first position, wherein plasma is generated on the target at the first position.

2. The sputtering apparatus according to claim 1, wherein the target held by the target holder contains gallium, gallium nitride, aluminum, aluminum nitride, indium, indium nitride, or a mixed crystal thereof.

3. A sputtering apparatus as described in claim 2, wherein the ratio of argon gas to nitrogen gas in the chamber when plasma is generated on the target at the first position is greater than the ratio of argon gas to nitrogen gas in the chamber when plasma is generated on the target at the second position.

4. A sputtering apparatus as described in any one of claims 1 to 3, wherein, in the second position, the target holding portion is positioned in a second direction of the substrate, the shield protrudes from the substrate holding portion in the second direction, and in the second direction, the distance from a first surface of the substrate holding portion to the tip of the shield is shorter than the distance from the first surface to the target.

5. The sputtering apparatus according to claim 4, wherein said shield covers at least a portion of the side surface of said substrate holder.

6. A sputtering apparatus as described in any one of claims 1 to 3, wherein, at the second position, the target holding portion is located in a second direction of the substrate holding portion, the shield protrudes from the target holding portion in a third direction opposite to the second direction, and the distance from the second surface of the target holding portion to the tip of the shield in the third direction is shorter than the distance from the second surface to the substrate or the substrate holding portion at the second position.

7. A sputtering apparatus as described in claim 6, wherein, in the second position, the target holding portion is located in a second direction of the substrate holding portion, the shield includes a first shield and a second shield, the first shield protrudes from the target holding portion in a third direction opposite to the second direction, and the second shield protrudes from the substrate holding portion in the second direction and is slidable in the second direction.

8. A sputtering apparatus as described in claim 7, wherein, at the second position, the target holding portion is positioned in a second direction of the substrate; at the first position, the shield is controlled to cover the surface of the target and has a shape that is bent in the second direction near the edge of the surface of the target; and at the second position, the shield moves to a position that does not overlap with the target when viewed in the second direction.

9. A sputtering apparatus comprising: a chamber; a substrate holder provided within the chamber for holding a substrate; a target holder for holding a target within the chamber so as to face the substrate; a magnet; and a position control unit for controlling the relative positional relationship between the substrate holder and the target holder in a first direction between a first position where the substrate and the target do not face each other and a second position where the substrate and the target face each other, wherein the target is configured to be located between the substrate and the magnet at the second position, and wherein, if a direction extending from an arbitrary point on the magnet and perpendicular to the surface of the substrate at the second position is defined as a third direction, the orientation of the magnet is controlled so that, at the first position, the angle between the direction of plasma generated at the target and the third direction, with the magnet as the reference, is larger than the angle between the direction of plasma and the third direction, with the magnet as the reference at the second position.

10. The sputtering apparatus according to claim 9, further comprising a shield, wherein the target holder is configured to hold a cylindrical target, the shield has an opening and covers an area other than the opening, and in the first position, the target is rotated around an axis at the center of the cylinder while the orientation of the magnet is controlled.

11. A sputtering apparatus comprising: a chamber; a substrate holding section provided within the chamber for holding a substrate; a target holding section for holding a target within the chamber so as to face the substrate; and a position control section for controlling the relative positional relationship between the substrate holding section and the target holding section in a first direction to a first position where the substrate and the target do not face each other, and a second position where the substrate and the target face each other, wherein at the second position the substrate holding section is located in a third direction of the target holding section, and wherein a position of the substrate at the first position is moved in the third direction from a position of the substrate at the second position, and a plasma is generated at the target.

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