Film forming apparatus and film forming method

Abstract

The present invention improves the performance of a film forming apparatus. As a means for achieving this, a film forming apparatus is used for performing, in separate steps, film forming on each of a front surface and a rear surface of an object on which to form a film and which is held by a sample holder, the film forming apparatus comprising a film forming chamber and a rotation mechanism RM. In a state in which a cup has been placed on the sample holder, first film forming is performed in the film formation chamber. Next, after each of the cup and the sample holder has been inverted by the rotation mechanism RM, second film forming is performed in the film forming chamber in a state in which the cup has been placed on the sample holder.

Description

Film Forming Apparatus and Film Forming Method

[0001] The present invention relates to a film forming apparatus and a film forming method.

[0002] For one surface and the other surface of a laser bar constituting a semiconductor laser, it is necessary to form films with different reflection characteristics in separate film forming steps. For example, Patent Document 1 (Japanese Unexamined Patent Application Publication No. 2024-024595) describes a technique for forming a film on a substrate using plasma.

[0003] Japanese Unexamined Patent Application Publication No. 2024-024595

[0004] When forming films on both surfaces of a laser bar, it is necessary to invert a sample holder that holds the laser bar between two film forming steps. However, if the inversion of the sample holder is done manually, the time and cost required for manufacturing the laser bar increase. The problem of the present application is to improve the performance of the film forming apparatus.

[0005] Other problems and novel features will become apparent from the description of this specification and the attached drawings.

[0006] Among the embodiments disclosed in the present application, the outline of typical ones will be briefly described as follows.

[0007] One embodiment of a film deposition apparatus is a film deposition apparatus that holds a film deposition object in a sample holder and has a first surface and a second surface opposite to the first surface, and performs a first film deposition on the second surface with the first surface protected by a cup, and a second film deposition on the first surface with the second surface protected by the cup, and comprises a film deposition chamber, a rotation mechanism that can rotate while holding the sample holder and the cup, and a gripping mechanism. Here, the sample holder has a first main surface and a second main surface opposite to the first main surface, and an opening that penetrates between the first main surface and the second main surface, the film deposition object is held in the opening of the sample holder, and the cup has a third main surface and a fourth main surface opposite to the third main surface. Furthermore, with the cup placed on the sample holder so that the first main surface and the fourth main surface face each other, the first film deposition is performed in the film deposition chamber. The rotating mechanism rotates the cup so that the third main surface and the fourth main surface face opposite directions, and rotates the sample holder so that the first main surface and the second main surface face opposite directions. The gripping mechanism moves the cup to a standby position before the rotating mechanism rotates the sample holder, and with the cup placed on the sample holder so that the second main surface and the third main surface face each other, the second film deposition is performed in the film deposition chamber.

[0008] One embodiment of the film deposition method involves a film deposition target object held in a sample holder, having a first surface and a second surface opposite the first surface, in which the first surface is protected by a cup while a film is deposited on the second surface for the first time, and the second surface is protected by the cup while a film is deposited on the first surface for the second time. The film deposition method comprises the steps of: (a) performing the first film deposition with the cup placed on the sample holder such that the first main surface of the sample holder and the fourth main surface of the cup face each other; (b) moving the cup to a standby position after step (a); (c) rotating the cup using a rotation mechanism after step (b) such that the fourth main surface and the third main surface opposite to the fourth main surface face each other, and rotating the sample holder such that the first main surface and the second main surface opposite to the first main surface face each other; and (d) performing the second film deposition with the cup placed on the sample holder such that the second main surface and the third main surface face each other after step (c). The sample holder has an opening that penetrates between the first main surface and the second main surface, and the object to be deposited is held within the opening of the sample holder.

[0009] According to one embodiment disclosed herein, the performance of the film deposition apparatus can be improved.

[0010] This is a perspective view showing a film deposition apparatus according to an embodiment. This is a perspective view showing a rotating mechanism according to an embodiment. This is a perspective view showing a sample holder and cup according to an embodiment. This is a perspective view showing a sample holder and cup according to an embodiment. This shows a side view of the bottom and side view of the cup according to an embodiment. This shows a side view of the sample holder and cup according to an embodiment, with parts of each cut off along line A-A in Figure 6. This is a side view of the sample holder and cup, with parts of each cut off along line B-B in Figure 6. This is an enlarged side view showing a cut-off of a part near the convex part of the cup according to an embodiment. This is a schematic diagram showing the operation of the film deposition apparatus according to an embodiment. This is a schematic diagram showing the operation of the film deposition apparatus following Figure 10. This is a schematic diagram showing the operation of the film deposition apparatus following Figure 11. This is a schematic diagram showing the operation of the film deposition apparatus following Figure 12. This is a schematic diagram showing the operation of the film deposition apparatus following Figure 13. This is a schematic diagram showing the operation of the film deposition apparatus following Figure 14. This is a schematic diagram showing the operation of the film deposition apparatus following Figure 15. This is a schematic diagram showing the operation of the film deposition apparatus, following Figure 16. This is a schematic diagram showing the operation of the film deposition apparatus, following Figure 17. This is a schematic diagram showing the operation of the film deposition apparatus, following Figure 18. This is a schematic diagram showing the operation of the film deposition apparatus, following Figure 19. This is a schematic diagram showing the operation of the film deposition apparatus, following Figure 20. This is a schematic diagram showing the operation of the film deposition apparatus, following Figure 21. This is a schematic diagram showing the operation of the film deposition apparatus, following Figure 22. This is a schematic diagram showing the operation of the film deposition apparatus, following Figure 23. This is a schematic diagram showing the operation of the film deposition apparatus, following Figure 24. This is a schematic diagram showing the operation of the film deposition apparatus, following Figure 25. This is a schematic diagram showing the operation of the film deposition apparatus, following Figure 26. This is a schematic diagram showing the operation of the film deposition apparatus, following Figure 27. This is a schematic diagram showing the operation of the film deposition apparatus, following Figure 28. This is a schematic diagram showing the operation of the film deposition apparatus, following Figure 29. This is a schematic diagram showing the operation of the film deposition apparatus, following Figure 30. This is a schematic diagram showing the operation of the film deposition apparatus, following Figure 31. This is a schematic diagram showing the operation of the film deposition apparatus, following Figure 32. Figure 33 is a schematic diagram showing the operation of the film deposition apparatus.

[0011] The embodiments will be described in detail below with reference to the drawings. In all the drawings used to describe the embodiments, the same reference numerals are used for members having the same function, and repeated descriptions of them will be omitted. In addition, in the following embodiments, descriptions of the same or similar parts will not be repeated unless it is particularly necessary.

[0012] In this application, "planar shape" refers to the shape of an object as seen from a planar perspective. Furthermore, "planar view" refers to viewing an object in the vertical direction.

[0013] (Embodiment) <Structure of the film deposition apparatus> The following describes a film deposition apparatus that deposits a film on both sides of an object by inverting the object within a vacuum chamber.

[0014] The film deposition apparatus of this embodiment is, for example, an apparatus for depositing films on a semiconductor laser (laser element, laser diode). The semiconductor laser consists of a semiconductor substrate (laser bar) comprising a p-type cladding layer on the upper surface, an n-type cladding layer on the lower surface, and an active layer between these layers. By passing an electric current between the upper and lower surfaces, it emits laser light with uniform properties such as wavelength and phase. When an electric current is passed through the semiconductor laser, the light generated in the semiconductor substrate is reflected by an HR coating (high reflection coating) covering one side of the semiconductor substrate and transmitted through an AR coating (anti-reflective coating) covering the other side before being emitted. Thus, since the HR (High Reflection) coating and the AR (Anti Reflection) coating are films with different reflection characteristics, they need to be deposited in separate processes. Hereinafter, the semiconductor substrate will be referred to as a laser bar. The semiconductor substrate constituting the laser bar is made of, for example, GaN or AlGaN.

[0015] Figure 1 is a perspective view showing the overall configuration of the film deposition apparatus 1 of this embodiment. As shown in Figure 1, the film deposition apparatus 1 comprises a process module PM, a process chamber (film deposition chamber) PR, and a load lock LL. The process module PM contains the control unit of the film deposition apparatus 1. The process module PM is connected to the process chamber PR and the load lock LL and controls the operation of the process chamber PR and the load lock LL. The process chamber PR is equipped with a chamber for performing, for example, ECR (Electron Cyclotron Resonance) plasma film deposition on the laser bar, which is the film to be deposited. The process chamber PR also includes a disc-shaped holding device for storing multiple disc-shaped sample holders on which the laser bar is fixed. The load lock LL is a device having a mechanism for transporting sample holders between the process chamber PR and the load lock LL, and a mechanism for rotating the sample holders. The load lock LL also includes a disc-shaped holding device for storing multiple sample holders. The main feature of this embodiment is the structure for rotating the sample holders in the load lock LL.

[0016] The load lock LL comprises a load lock chamber LR, a rotating mechanism RM positioned above the load lock chamber LR, and a gripping mechanism GM positioned above the rotating mechanism RM. The load lock chamber LR and the process chamber PR are connected to each other, allowing for the transport of sample holders between them while maintaining a vacuum inside. The chambers constituting the rotating mechanism RM and the load lock chamber LR are connected to each other, allowing for the transport of sample holders between them while maintaining a vacuum inside. The rotating mechanism RM and the load lock chamber LR are mechanisms (transportation units) capable of automatically transporting objects within a vacuumed environment.

[0017] Here, the direction in which the load lock chamber LR and the process chamber PR are connected is defined as the "front-to-back direction," and the direction in which the load lock chamber LR, the rotating mechanism RM, and the gripping mechanism GM overlap is defined as the "up-down direction." Furthermore, the direction perpendicular to both the front-to-back and up-and-down directions is defined as the "left-to-right direction." In addition, regarding the front-to-back direction, the direction of the process chamber PR relative to the load lock chamber LR is defined as the "front," and the direction of the load lock chamber LR relative to the process chamber PR is defined as the "rear." Regarding the up-and-down direction, the side where the load lock chamber LR is located is defined as "downward," and the side where the gripping mechanism GM is located is defined as "upward."

[0018] Figure 2 is a perspective view showing the rotating mechanism RM. As shown in Figure 2, the rotating mechanism RM comprises a container (chamber) 8 whose interior can be evacuated, a lid 9 provided on the container 8, a rotating part RP inside the container 8, and arms AM1 and AM2 inside the container 8. The lid 9 has a window 10 for observing the inside of the container 8. The lid 9 is provided on the left side of the container. A hole 7 is provided on the bottom surface inside the container 8, which leads to the inside of the load lock chamber LR. In Figure 2, a stage ST rises up into the container 8 from inside the load lock chamber LR, and a sample holder SH is placed on the stage ST. In other words, there is a hole in the bottom surface inside the container 8, and this hole connects the inside of the container 8 to the inside of the load lock chamber LR. A cup (anti-rotation material) CP is placed on the sample holder. The sample holder SH and the cup CP have a disc shape with approximately the same diameter. The rotating part RP is provided so as to be rotatable around an axis that extends in the left-right direction. A portion of the rotating part RP forms the right side of the inner wall of the container 8. A pair of support columns P1, which support arms AM1 and AM2 respectively, are fixed to the rotating part RP, and arms AM1 and AM2 and support columns P1 are rotatable together with the rotating part RP.

[0019] Figure 3 is a perspective view showing the sample holder SH and the cup CP on the sample holder SH spaced apart from each other. Figure 4 is a perspective view showing the cup CP placed on the sample holder SH. Figures 3 and 4 are perspective views of the sample holder SH and cup CP from opposite sides (e.g., top and bottom). Figure 5 shows the bottom and side views of the cup CP side by side. Figure 6 shows the bottom and side views of the structure with the cup CP placed on the sample holder SH side by side.

[0020] As shown in Figures 3 to 6, the planar shape of the sample holder SH is circular, and the planar shape of the cup CP is approximately circular. The sample holder SH has a circular main surface SF1 and a circular main surface SF2 opposite to the main surface SF1 in the vertical direction. The cup CP has a roughly circular main surface SF3 and a circular main surface SF4 opposite to the main surface SF3 in the vertical direction. In a plan view, each of the left and right ends of the cup CP is provided with a linear notch H1 extending in the front-to-back direction.

[0021] In a plan view, the sample holder SH, which is roughly disc-shaped, has an opening OP1 in the center that penetrates vertically between the main surfaces SF1 and SF2 of the sample holder SH. The planar shape of the opening OP1 is, for example, rectangular. When performing a series of processes to deposit a film on the laser bar LB, two spacers SP1 are placed inside the opening OP1, and multiple laser bars LB and spacers SP2 are alternately placed between these spacers SP1. For example, in the front-to-back direction, between one end and the other end of the opening OP1, spacers SP1, multiple laser bars LB and spacers SP2 arranged alternately, and spacers SP1 are arranged in order. In other words, multiple laser bars LB are held (placed) inside the opening OP1.

[0022] In the front-to-back direction, the width of spacer SP1 is greater than that of both the laser bar LB and spacer SP2. In the left-to-right direction, the widths of spacers SP1 and SP2 are approximately equal to the width of, for example, the opening OP1, while the width of the laser bar LB is likely to be smaller than the width of the opening OP1. This is because it is difficult to prepare a laser bar LB with a width that matches the width of the opening OP1. As a result, a gap is created between the end of the laser bar LB and the end of the opening OP1 in the left-to-right direction.

[0023] The laser bars LB arranged within the opening OP1 are, for example, formed by cleaving a single semiconductor substrate, and the cleavage surfaces of adjacent laser bars LB in the front-to-back direction are oriented in the up-and-down direction.

[0024] The circular main surface SF1 of the sample holder SH has two circular protrusions C1 and C2 that project upward, spaced radially apart from each other. In a plan view, the circular protrusion C2 is positioned inside the circular protrusion C1, and the opening OP1 is located inside the circular protrusion C2. The circular protrusions C1 and C2 are also provided on the circular main surface SF2 of the sample holder SH, and they project downward from the sample holder SH. The circular protrusions C1 formed on the main surface SF1 (upper surface) and the main surface SF2 (lower surface) of the sample holder SH overlap each other in a plan view. Similarly, the circular protrusions C2 formed on the main surface SF1 and the main surface SF2 of the sample holder SH overlap each other in a plan view.

[0025] In a plan view, a protrusion PP is provided in the center of the roughly disc-shaped cup CP, which is slidable along the vertical direction (axial direction). A circular protrusion C3 projecting upward is provided on the roughly circular main surface SF3 of the cup CP. Similarly, a circular protrusion C3 projecting downward is provided on the roughly circular main surface SF4 of the cup CP. The circular protrusions C3 formed on the main surface SF3 side and the main surface SF4 side of the cup CP overlap each other in a plan view. Here, a part of the annular structure constituting the circular protrusion C3 is interrupted at two locations that sandwich the protrusion PP in the front-rear direction. However, the circular protrusion C3 may have a continuously formed annular structure in a plan view.

[0026] Figure 7 is a side view showing a portion of the sample holder SH and cup CP cut away along line A-A in Figure 6. Figure 8 is a side view showing a portion of the sample holder SH and cup CP cut away along line B-B in Figure 6. The protruding portion PP comprises a trapezoidal portion T1 that protrudes upward from the main surface SF3 of the sample holder SH and a trapezoidal portion T2 that protrudes downward from the main surface SF4 of the sample holder SH. The trapezoidal portions T1 and T2 are connected to each other by two support columns PL. Here, a portion of the surface of each of the trapezoidal portions T1 and T2 is covered by a thin metal plate (cover material, anti-friction plate) CV that is detachable from the trapezoidal portions T1 and T2. The protruding portion PP is composed of the trapezoidal portion T1, the trapezoidal portion T2, and the two support columns PL. The two support columns PL are arranged side by side in the left-right direction. The support column PL is movable vertically within a through hole that penetrates the cup CP vertically. Here, vertical movement refers to directions perpendicular to the main surfaces SF3 and SF4 of the cup CP, respectively. The protrusion PP moves (slides) toward either the main surface SF3 side or the main surface SF4 side of the cup CP according to gravity.

[0027] Figure 9 is an enlarged side view showing a section of the cup CP near the convex PP, with a break in place. Figure 9 is an enlarged side view showing a section of Figure 7. As shown in Figure 9, the trapezoidal portion T1 has a cross-sectional structure in which its width in the front-to-back direction increases as it moves away from the main surface SF3 of the cup CP. Similarly, the trapezoidal portion T2 has a cross-sectional structure in which its width in the front-to-back direction increases as it moves away from the main surface SF4 of the cup CP. In other words, the upper base of the trapezoid is located on the cup CP side, and the lower base is located outside the upper base in the vertical direction relative to the cup CP.

[0028] Of the surfaces of the trapezoidal portion T1, the surface located at the bottom of the trapezoid and furthest from the main surface SF3 is parallel to the main surface SF3 and its entire surface is covered by plate CV. Similarly, of the surfaces of the trapezoidal portion T2, the surface located at the bottom of the trapezoid and furthest from the main surface SF4 is parallel to the main surface SF4 and its entire surface is covered by plate CV. The surface of the trapezoidal portion T1 or T2 that is entirely covered by plate CV is the surface that faces the upper surfaces of each of the multiple laser bars via plate CV when the cup CP is placed on the sample holder SH. The surface of the trapezoidal portion T1 or T2 that is entirely covered by plate CV overlaps with the opening OP1 in a plan view when the cup CP is placed on the sample holder SH, and for example, in a plan view, it has an area equivalent to that of the opening OP1.

[0029] The front-to-back ends of the plate CV covering the trapezoidal portion T1 are bent at an acute angle toward the main surface SF3 so as to sandwich the ends of the trapezoidal portion T1, following the shape of the trapezoidal portion T1. As a result, the plate CV is locked (held) to the trapezoidal portion T1. The front-to-back ends of the plate CV covering the trapezoidal portion T2 are bent at an acute angle toward the main surface SF4 so as to sandwich the ends of the trapezoidal portion T2, following the shape of the trapezoidal portion T2. ​​As a result, the plate CV is locked (held) to the trapezoidal portion T2.

[0030] The sample holder SH is responsible for holding the laser bar LB, which is the object to be deposited. Multiple laser bar LBs are held within the opening OP1, sandwiched between a pair of spacers SP1 along with multiple spacers SP2. Plasma deposition is performed on the laser bar LBs in the process chamber PR (see Figure 1). In this plasma deposition, plasma is generated in the process chamber PR, and ions excited by the plasma are collided with a target placed in the process chamber PR. Sputtered particles ejected from the target are deposited on the surface of the laser bar LBs to form the film.

[0031] Here, films with different properties are formed on one side of the laser bar LB and on the opposite side of that side by different film deposition processes. The cup CP plays the role of covering one main surface of the sample holder SH in order to protect (cover) the opposite side of the laser bar LB when a film is deposited on one side of the laser bar LB. As shown in Figure 8, when the main surface SF1 of the sample holder SH is covered with the cup CP, the circular protrusion C3 protruding from the main surface SF4 of the cup CP facing the main surface SF1 fits between the circular protrusions C1 and C2 protruding on the main surface SF1. This prevents sputtered particles that have wrapped around to the main surface SF1 side of the sample holder SH from adhering to the surface of the laser bar LB on the main surface SF1 side during the film deposition process on the main surface SF2 side.

[0032] However, as explained using Figure 3, a gap may occur between the end of the laser bar LB and the end of the opening OP1 in the left-right direction. In this case, during the process of forming a film on the lower surface of the laser bar LB on the main surface SF2 side, sputtered particles may wrap around from this gap and adhere to the upper surface of the laser bar LB on the main surface SF1 side. To prevent sputtered particles from unintentionally adhering to the upper surface of the laser bar LB in this manner, in this embodiment, the upper surface of the laser bar LB is protected by the convex portion PP and the plate CV. In the film formation process on the lower surface of the laser bar LB, the sample holder SH is set up so that the main surfaces SF1 and SF2 are aligned with the horizontal plane. At this time, the convex portion PP is pulled downward by gravity, that is, towards the laser bar LB, and the plate CV covering the trapezoidal portion T2 comes into contact with the multiple laser bar LBs so as to cover the upper surface of each of the multiple laser bar LBs. By performing the film formation process in this state, it is possible to form a film on the lower surface of the laser bar LB while protecting the upper surface of the laser bar LB.

[0033] To perform film deposition on both sides of the laser bar LB, after the first deposition process is performed on one side of the laser bar LB, the sample holder SH is inverted and the second deposition process is performed. At this time, the main surface SF2 of the sample holder SH, which was exposed from the cup CP during the first deposition process, is covered by the cup CP during the second deposition process. Furthermore, in this embodiment, the sample holder SH is covered by a main surface SF3 of the cup CP, which is different from the main surface SF4 of the cup CP that covered the sample holder SH during the first deposition process, during the second deposition process. In other words, both the sample holder SH and the cup CP are rotated between the first and second deposition processes.

[0034] The following describes how the first film deposition process, the rotation of the sample holder SH, the rotation of the cup CP, and the second film deposition process are performed within a vacuum-sealed film deposition apparatus 1 without exposing the sample holder SH to the atmosphere.

[0035] <Rotation Mechanism> The structure of arms AM1 and AM2, used for rotating the sample holder SH and the cup CP in the rotation mechanism RM, and arm AM3, used for retracting the cup CP, will be explained using Figures 10 to 14. The rotation mechanism RM has a mechanism that allows rotation while holding either the sample holder SH or the cup CP using arms AM1 and AM2.

[0036] Figures 10 and 12 are perspective views showing arms AM1 and AM2. Figure 11 is a side view showing arms AM1 and AM2. As shown in Figures 10 and 11, arms AM1 and AM2 have similar structures. Therefore, the structure of arm AM1 will be described in detail here, while the explanation of the structure of arm AM2 will be simplified.

[0037] Within the rotating mechanism RM, a pair of arms AM1 are provided. Each arm AM1 extends in an L-shape in a plan view. Each of the pair of arms AM1 has two disc-shaped holding parts R1 at its tip for holding a sample holder SH or a cup CP. The two holding parts R1 of one arm AM1 and the two holding parts R1 of the other arm AM1 are spaced apart in a plan view, straddling the space where the sample holder SH or cup CP is placed. Of the tips of the L-shaped arms AM1, the tip opposite to the tip with the two holding parts R1 is supported by a sliding part SL1 that can slide in the left-right direction. Here, a cylindrical component (e.g., a bolt) provided on the sliding part SL1 penetrates the tip of the arm AM1 in the vertical direction. The sliding part SL1 is rotatable together with the rotating part RP about an axis that extends in the left-right direction.

[0038] The L-shaped arm AM1 is supported by a support column P1 between a tip end equipped with two holding parts R1 and a tip end supported by a sliding part SL1. The arm AM1 is rotatable about the central axis of the cylindrical support column P1. As shown in Figure 12, when the sliding part SL1 slides to the left, each of the pair of arms AM1 rotates about the central axis (fulcrum F1) of the cylindrical support column P1. As a result, the holding parts R1 at the tips of each arm AM1 move away from each other. In other words, the arm AM1 opens. When the sliding part SL1 slides to the right, the holding parts R1 at the tips of each arm AM1 move towards each other. In other words, the arm AM1 closes. In the closed state, the arm AM1 can hold a sample holder SH or a cup CP with its four holding parts R1.

[0039] Arms AM2 are provided in pairs, similar to arms AM1. Each arm AM2 has an L-shaped planar shape, and its tip is equipped with two disc-shaped holding parts R2. The other tip of each arm AM2 is supported by a sliding part SL2 that rotates together with a pivot part RP around a central axis in the left-right direction. Arms AM2 are rotatable around the central axis of the support column P1 as a pivot point F1, similar to arms AM1. As shown in Figure 12, when the sliding part SL2 slides to the left, each of the pair of arms AM2 rotates around the central axis (pivot point F1) of the cylindrical support column P1. As a result, the holding parts R2 at the tips of each arm AM2 move away from each other. In other words, arms AM2 open. When the sliding part SL2 slides to the right, the holding parts R2 at the tips of each arm AM2 move towards each other. In other words, arms AM2 close. When closed, the arm AM2 can hold the sample holder SH or cup CP using its four holding parts R2.

[0040] As shown in Figure 11, sliding parts SL1 and SL2 have similar structures. In Figure 12, both sliding parts SL1 and SL2 are shown extended to the left, but sliding parts SL1 and SL2 can operate independently of each other. In other words, the opening and closing operations of arms AM1 and AM2 can be controlled independently.

[0041] Figures 13 and 14 are perspective views showing the holding mechanism, arm AM3. The rotating mechanism RM is not shown in Figures 13 and 14. As shown in Figure 13, arm AM3 is a holding mechanism provided at the lower end of the gripping mechanism GM and is used to hold the cup CP. A pair of arms AM3 are provided inside the rotating mechanism RM. Arms AM3 are positioned in the upper part (near the ceiling) of the container 8 of the rotating mechanism RM. When viewed from the front and rear, the side shape of each of the pair of arms AM3 is L-shaped. A holding portion R3 extending in the front and rear direction is provided at the lower tip of each of the pair of arms AM3. Of the tips of the L-shaped arms AM3, the tip opposite to the tip where the holding portion R3 is provided is supported by a sliding portion SL3 that can slide in the vertical direction. Of the L-shaped arm AM3, the portion between the tip where the holding portion R3 is provided and the tip supported by the sliding portion SL3 is fixed so as to be rotatable about an axis extending in the front-rear direction to a support portion SP which is movable up and down by the gripping mechanism GM. The support portion SP, arm AM3, and sliding portion SL3 are all movable up and down by the gripping mechanism GM.

[0042] As shown in Figure 14, when the sliding part SL3 slides downward, each of the pair of arms AM3 rotates around the central axis (fulcrum F2). As a result, the holding parts R3 at the ends of each of the pair of arms AM3 move away from each other. In other words, the arms AM3 open. When the sliding part SL3 slides upward, the holding parts R3 at the ends of each of the pair of arms AM3 move towards each other. In other words, the arms AM3 close.

[0043] <Film forming apparatus operation>In the film forming process, first, as shown in FIGS. 3 and 4, a cup CP is placed on a sample holder SH having a plurality of laser bars LB arranged at the central portion, and the sample holder SH is placed in the process chamber PR shown in FIG. 1. As a process of placing the sample holder SH in the process chamber PR, for example, the following process may be performed. First, the sample holder SH is automatically or manually placed in the load lock chamber LR. At this time, a disk-shaped holding device capable of placing a plurality of sample holders SH is provided in the load lock chamber LR, and a plurality of sample holders SH may be placed on the holding device. Next, the interiors of the load lock chamber LR, the rotation mechanism RM, and the process chamber PR are evacuated. Next, a robot arm provided in the load lock chamber LR transports a predetermined sample holder SH in the load lock chamber LR into the process chamber PR. A disk-shaped holding device capable of placing a plurality of sample holders SH may be provided in the process chamber PR. Here, it is assumed that the sample holder SH has its first main surface (main surface SF1 shown in FIG. 7) facing upward and its second main surface (main surface SF2 shown in FIG. 7) facing downward. Further, it is assumed that the cup CP covering the sample holder SH has its third main surface (main surface SF3 shown in FIG. 7) facing upward and its fourth main surface (main surface SF4 shown in FIG. 7) facing downward.

[0044] Next, in the process chamber PR, first film formation (plasma film formation) is performed on the bottom surface on the second main surface side of the laser bar LB disposed on one sample holder SH. At this time, the first main surface side of the sample holder SH is covered with the cup CP, and the surface of the laser bar LB on the first main surface side is covered with a plate CV as shown in FIG. 9, so that film formation does not occur. Next, using the robot arm, the sample holder SH having the laser bar LB formed with a film on the second main surface side is transported from the process chamber PR into the load lock chamber LR, and then placed on a stage ST (see FIGS. 2 and 15) capable of moving up and down. Next, as shown in FIG. 15, the stage ST is moved to the upper standby position A1.

[0045] Figures 15 to 34 are schematic diagrams showing the operation of the film deposition apparatus and illustrating the structure within the rotating mechanism RM. The central circle in Figures 15 to 34 represents the region within the container 8 that constitutes the rotating mechanism RM where the rotating part equipped with arms AM1 and AM2 rotates. At the center of this region is the rotation position B1, which is the region where the sample holder SH or cup CP is rotated. Above rotation position B1 is a standby position A2 where the sample holder SH or cup CP is grasped and held in standby (retracted). Standby position A1 is located directly below rotation position B1, and standby position A2 is located directly above rotation position B1.

[0046] At rotation position B1, arms AM1 and AM2, as described in Figures 10 to 12, are positioned in a closed state. Figures 15 to 34 show the holding part R1, which is provided at the tip of arm AM1 to hold the sample holder SH or cup CP, and the holding part R2, which is provided at the tip of arm AM2 to hold the sample holder SH or cup CP. At standby position A2, arm AM3, as described in Figures 13 and 14, is positioned in a closed state. In Figures 15 to 34, hatching is applied to the holding part R1 and the trapezoidal portion T2. ​​In Figures 15 to 33, hatching is applied to a part of the laser bar LB on the side that was not coated in the first coating process described above. The operation of rotating (reversing) the sample holder SH and cup CP will be described below using Figures 15 to 34.

[0047] As shown in Fig. 15, after placing the sample holder SH and the cup CP on the stage ST at the standby position A1, as shown in Fig. 16, open each of the arms AM1 and AM2. Next, as shown in Fig. 17, by moving the stage ST upward, the cup CP on the sample holder SH is moved to the rotational position B1. Here, it may be confirmed that the cup CP is present at the rotational position B1 using a sensor (e.g., a photoelectric sensor). Next, as shown in Fig. 18, close each of the arms AM1 and AM2. As a result, the holding portion R2 is disposed under a part of the peripheral edge of the cup CP, and the holding portion R1 is disposed above a part of the peripheral edge of the cup CP. Thereafter, lower the stage ST on which the sample holder SH is placed to the standby position A1. By lowering the stage ST, a part of the peripheral edge of the cup CP is held by the holding portion R2 (arm AM2).

[0048] Next, as shown in Fig. 19, by rotating the arms AM1 and AM2 by 180°, the cup CP is rotated by 180°. That is, the cup CP is rotated so that the third main surface and the fourth main surface of the cup CP face in opposite directions. As a result, the third main surface of the cup CP faces downward, and the fourth main surface faces upward. By this rotation, the cup CP is held by the holding portion R1 (arm AM1). Note that due to this rotation, the trapezoidal portion T1 located below the cup CP is pulled by gravity and moves downward. That is, the entire convex portion PP moves downward.

[0049] Next, as shown in Figure 20, after opening arm AM2, arm AM3 is opened. Then, as shown in Figure 21, arm AM3 is moved to the lower rotation position B1 and closed, so that arm AM3 holds the cup CP. Here, the two ends of arm AM3 are gripping both sides of the cup CP. The ends of the cup CP that are gripping the cup CP are, for example, the notches H1 shown in Figure 3. Alternatively, for example, the two ends of arm AM3 may be inserted under a part of the peripheral edge of the cup CP that is separated from the holding part R2, thereby holding (placing) the cup CP on the two ends of arm AM3. Here, a sensor may be used to confirm that arm AM3 is holding the cup CP. Next, as shown in Figure 22, arm AM3 is moved upward to move the cup CP to the standby position A2. Here, a sensor may be used to confirm that the cup CP is in the standby position A2. Next, arm AM2 is closed.

[0050] Next, as shown in Figure 23, rotate arms AM1 and AM2 by 180°. At this time, rotate arms AM1 and AM2 in the opposite direction to the rotation direction of arms AM1 and AM2 as explained using Figure 19. This allows the sample holder SH and cup CP to be rotated even if the rotatable angle of arms AM1 and AM2 is 180°. Next, as shown in Figure 24, open arms AM1 and AM2 respectively. Next, move the stage ST upward to move the sample holder SH to rotation position B1. Here, a sensor (e.g., a photoelectric sensor) may be used to confirm that the sample holder SH is at rotation position B1.

[0051] Next, as shown in Figure 25, arms AM1 and AM2 are closed. This positions the holding part R2 below a portion of the periphery of the sample holder SH, and the holding part R1 above a portion of the periphery of the sample holder SH. Then, the stage ST is lowered to the standby position A1. Lowering the stage ST causes a portion of the periphery of the sample holder SH to be held by the holding part R2 (arm AM2). Next, as shown in Figure 26, arms AM1 and AM2 are rotated 180°, thereby rotating the sample holder SH 180°. In other words, the sample holder SH is rotated so that its first main surface and second main surface are facing opposite directions. As a result, the first main surface of the sample holder SH faces downwards, and the second main surface faces upwards. This rotation holds the sample holder SH by the holding part R1 (arm AM1), and the surface of the laser bar LB deposited in the first deposition process faces upward. At this time, arms AM1 and AM2 are rotated in the same direction as the rotation direction of arms AM1 and AM2 as explained using Figure 19. This allows the sample holder SH and cup CP to be rotated even if the rotatable angle of arms AM1 and AM2 is 180°.

[0052] Next, as shown in Figure 27, after opening arm AM1, the stage ST is moved upward. Specifically, the stage ST is raised to a position on the rotation position B1 side where it can hold the sample holder SH. Next, as shown in Figure 28, after opening arm AM2, the stage ST is moved downward. This moves the stage ST and sample holder SH to the standby position A1. Next, as shown in Figure 29, arms AM1 and AM2 are closed. After that, arms AM1 and AM2 are rotated 180°. At this time, arms AM1 and AM2 are rotated in the same direction as the rotation direction of arms AM1 and AM2 as explained using Figure 23.

[0053] Next, as shown in Figure 30, after opening arm AM1, arm AM3 is moved downward. This moves cup CP to rotation position B1. Next, as shown in Figure 31, arm AM3 is moved upward. This moves arm AM3 to standby position A2. Next, as shown in Figure 32, after closing arm AM1, stage ST and sample holder SH on stage ST are moved upward. Specifically, stage ST and sample holder SH are raised to a position where cup CP can be held on sample holder SH.

[0054] Next, as shown in Figure 33, after opening arm AM2, the stage ST is moved downward. This moves the stage ST, the sample holder SH and cup CP on the stage ST, to the standby position A1. Next, as shown in Figure 34, arms AM1 and AM2 are closed.

[0055] Subsequently, although not shown in the diagram, the sample holder SH and cup CP, which have been lowered into the load lock chamber LR by the stage ST, are transported into the process chamber PR by a robot arm located within the load lock chamber LR. At this point, due to the rotational movement described using Figures 15 to 34, the sample holder SH has its second main surface facing upwards and its first main surface facing downwards. The cup CP, which is placed over the second main surface of the sample holder SH, has its fourth main surface facing upwards and its third main surface facing downwards.

[0056] Next, in the process chamber PR, a second film deposition (plasma deposition) is performed on the bottom surface of the first main surface of the laser bar LB placed in the sample holder SH. At this time, the second main surface of the sample holder SH is covered by the cup CP, and the surface of the laser bar LB on the second main surface side is covered by the plate CV, so no film is deposited there.

[0057] Next, after increasing the pressure inside the deposition apparatus 1 to atmospheric pressure, the sample holder SH and cup CP, for which the second deposition has been completed, are removed from the deposition apparatus 1. This completes the deposition process in this embodiment. Subsequently, the two plates CV that were locked to the protrusions PP of the cup CP are replaced with new ones before the cup CP is used again in the deposition process. Here, a vacuum state is maintained inside the deposition apparatus 1 from the time the sample holder SH and cup CP are placed in the deposition apparatus 1 before the first deposition process until the sample holder SH and cup CP are removed from the deposition apparatus 1 after the second deposition process. The series of operations, including the first deposition process, the rotation operation described using Figures 15 to 34, and the second deposition process, are performed automatically, for example, by a control unit provided in the process module PM.

[0058] <Effects of the Embodiment> When forming a film on a laser bar, films with different properties are formed on the first surface of the laser bar and on the second surface opposite to the first surface. However, it is necessary to prevent foreign matter such as sputtered particles from adhering to the second surface during the film formation process on the first surface. Therefore, the first surface is protected by a cup while the film is formed on the first surface, and then the first surface is protected by the cup while the film is formed on the second surface. At this time, after the first film formation process, it is conceivable to remove the sample holder and cup from the film formation apparatus, manually invert the sample holder, place the cup back on the sample holder, and then put the sample holder and cup back into the film formation apparatus to perform the second film formation process.

[0059] In this case, manual inversion is required between the first and second film deposition processes. Furthermore, before the second deposition process, the sample holder and cup must be removed from the deposition apparatus. This requires returning the vacuum created during the first deposition process to atmospheric pressure, returning the inverted sample holder and cup to the apparatus, and then vacuuming the apparatus again. Therefore, removing and inverting the sample holder and cup during the two deposition processes increases the time and cost required for laser bar manufacturing.

[0060] Furthermore, when a cleaved laser bar comes into contact with oxygen, the cleavage surface oxidizes, leading to a decrease in the laser bar's performance. When oxidation occurs, multiple energy levels are generated on the cleavage surface of the semiconductor substrate constituting the laser bar. These energy levels on the cleavage surface induce absorption and non-emissive recombination of laser light during laser oscillation, resulting in a localized temperature increase. This temperature increase causes a decrease in the output power of the semiconductor laser. Therefore, it is desirable to minimize the time (opportunity) for the laser bar to be exposed to oxygen after cleaving the semiconductor substrate.

[0061] As described above, if manual reversal is performed between the first and second film deposition processes, the sample holder and cup must be removed from the deposition apparatus before the second deposition process. At that time, the laser bar is exposed to oxygen in the atmosphere, increasing the likelihood of oxidation occurring on the surface of the laser bar.

[0062] Therefore, in this embodiment, as explained with reference to Figures 1 to 34, the film deposition apparatus 1 is equipped with a rotating mechanism RM and a gripping mechanism GM, and the sample holder SH and cup CP are automatically inverted within the film deposition apparatus 1 between the first and second film deposition processes. Here, the cup CP is first rotated (see Figures 17 to 19), then the cup CP is moved to the standby position A2 (see Figures 20 to 22), and in that state, the sample holder SH is rotated (see Figures 24 to 28).

[0063] According to the film deposition apparatus of this embodiment, there is no need to manually rotate the sample holder SH and cup CP before the second film deposition process. Furthermore, since the sample holder SH and cup CP are rotated automatically within the film deposition apparatus 1, there is no need to vacuum the inside of the film deposition apparatus 1 again before the second film deposition process. In other words, a vacuum state is maintained inside the film deposition apparatus 1, including the process chamber PR and the rotating mechanism RM, while the first film deposition process, the rotation of cup CP and sample holder SH by the rotating mechanism RM, and the second film deposition process are performed in sequence. In other words, a vacuum state is maintained around the laser bar LB. Therefore, the laser bar LB can be deposited in a short time, improving work efficiency. That is, the performance of the film deposition apparatus 1 can be improved.

[0064] Furthermore, contamination of the laser bar LB by exposure to the atmosphere is prevented, thus preventing the occurrence of film deposition defects. In other words, an improvement in the film quality of the film formed in the second deposition process can be expected. In addition, since the opportunity (time) for the surface of the film to be deposited on the laser bar LB to be exposed to oxygen before deposition is reduced, a decrease in the performance of the laser bar LB can be prevented.

[0065] Furthermore, in this embodiment, not only the convex PP (trapezoidal portions T1, T2) shown in Figure 9, but also a plate CV is used to protect the surface of the laser bar LB, which is not the target of film deposition. This prevents foreign matter from adhering to the surface of the laser bar LB, which is not the target of film deposition, compared to when a plate CV is not used. Thus, a decrease in the performance of the laser bar LB can be prevented.

[0066] Furthermore, in this process, the plate CV used to protect the surface of the laser bar LB in the first deposition process is not used again to protect the surface of the laser bar LB in the second deposition process. In other words, after the first deposition process, by inverting the plate CV as explained using Figures 17 to 19, a new plate CV that was not used to protect the surface of the laser bar LB in the first deposition process is used to protect the surface of the laser bar LB in the second deposition process. Therefore, compared to the case where the same plate CV is used in both the first and second deposition processes, it is possible to prevent foreign matter from adhering to the film formed in the first deposition process. Thus, a decrease in the performance of the laser bar LB can be prevented.

[0067] Although the present invention has been specifically described above based on embodiments, it goes without saying that the present invention is not limited to the above embodiments and can be modified in various ways without departing from its essence.

[0068] 1. Film deposition apparatus 7. Hole 8. Container 9. Lid 10. Window A1, A2 Standby position AM1, AM2, AM3 Arm B1 Rotation position C1, C2, C3 Circular protrusion CP Cup CV Plate F1, F2 Pivot GM Gripping mechanism H1 Notch LB Laser bar LL Load lock LR Load lock chamber OP1 Opening P1, PL Support column PM Process module PP Protrusion PR Process chamber R1, R2, R3 Holding part RM Rotation mechanism RP Rotating part SF1, SF2, SF3, SF4 Main surface SH Sample holder SL1, SL2, SL3 Sliding part SP Support part SP1, SP2 Spacer ST Stage T1, T2 trapezoidal section

Claims

1. A film deposition apparatus for a film-depositing object held in a sample holder and having a first surface and a second surface opposite to the first surface, wherein the first surface is protected by a cup while a film deposition is performed on the second surface, and the second surface is protected by the cup while a film deposition is performed on the first surface, comprising: a film deposition chamber; a rotating mechanism that can rotate while holding the sample holder and the cup; and a gripping mechanism, wherein the sample holder has a first main surface and a second main surface opposite to the first main surface, and an opening that penetrates between the first main surface and the second main surface, the film-depositing object is held in the opening of the sample holder, and the cup has a third main surface and a fourth main surface opposite to the third main surface, and the first film deposition is performed in the film deposition chamber with the cup placed on the sample holder so that the first main surface and the fourth main surface face each other. A film deposition apparatus comprising: a rotating mechanism that rotates the cup so that the third main surface and the fourth main surface are facing opposite directions, and the sample holder so that the first main surface and the second main surface are facing opposite directions; a gripping mechanism that moves the cup to a standby position before the rotating mechanism rotates the sample holder; and a second film deposition procedure performed in the film deposition chamber with the cup placed on the sample holder so that the second main surface and the third main surface face opposite each other.

2. A film deposition apparatus according to claim 1, wherein a vacuum state is maintained inside the film deposition chamber and the rotating mechanism while the first film deposition, the rotation of the cup and the sample holder by the rotating mechanism, and the second film deposition are performed in order.

3. A film-forming apparatus according to claim 1, wherein the cup has a first protrusion projecting onto the fourth main surface and a second protrusion projecting onto the third main surface, a first plate covering the surface of the first protrusion protects the first surface of the object to be film-formed during the first film-forming, and a second plate covering the surface of the second protrusion protects the second surface of the object to be film-formed during the second film-forming.

4. A film deposition method for a film to be deposited on an object held in a sample holder and having a first surface and a second surface opposite to the first surface, wherein the first surface is protected by a cup and a film is deposited on the second surface for the first time, and the second surface is protected by the cup and a film is deposited on the first surface for the second time, comprising: (a) a step of performing the first film deposition with the cup placed on the sample holder such that the first main surface of the sample holder and the fourth main surface of the cup face each other; (b) a step of moving the cup to a standby position after step (a); (c) a step of rotating the cup using a rotation mechanism after step (b) such that the fourth main surface and the third main surface opposite to the fourth main surface face each other, and rotating the sample holder such that the first main surface and the second main surface opposite to the first main surface face each other; (d) After step (c), a step of performing the second film formation with the cup placed on the sample holder such that the second main surface and the third main surface face each other, wherein the sample holder has an opening that penetrates between the first main surface and the second main surface, and the object to be film-formed is held within the opening of the sample holder.

5. A film deposition method according to claim 4, wherein a vacuum state is maintained around the object to be deposited on while steps (a) to (d) are carried out in order.

6. A film-forming method according to claim 4, wherein the cup has a first protrusion projecting onto the fourth main surface and a second protrusion projecting onto the third main surface, a first plate covering the surface of the first protrusion protects the first surface of the object to be filmed during the first film-forming, and a second plate covering the surface of the second protrusion protects the second surface of the object to be filmed during the second film-forming.

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