Film deposition apparatus

Abstract

To provide a film deposition apparatus capable of suppressing the expansion / contraction of a deposition-preventive plate due to thermal expansion.SOLUTION: A film deposition apparatus 1 has: a chamber 20 of which inside can be evacuated; a table that is arranged in the chamber 20 and holds a plurality of works 10; a film deposition part 40 that has a plasma generator P1 for making gas introduced to the chamber 20 into plasma, and deposits a film on the work 10 held on the table; a deposition preventive plate 410 that is arranged ina a manner to surround a treatment space 41 in which the film deposition on the work 10 is performed by the film deposition part 40, and prevents adhesion of a film deposition material to the inside of the chamber 20; a cooling block 420 that has a contact surface 421 coming into direct contact with the deposition preventive plate 410, and cools the deposition preventive plate 410; and a flow channel 422 which is arranged in the cooling block 420 and through which a cooling medium flows.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a film forming apparatus. [Background technology]

[0002] There is a film forming apparatus that deposits a film material by sputtering and nitrides the deposited film material while circulating and transporting a workpiece on a rotating table in a vacuum chamber (see Patent Document 1). In such a film forming apparatus, a film forming processing section that forms a film and a film processing section that performs nitriding are provided in one chamber. In the film forming processing section, the workpiece is passed through a position facing a target made of the film material, so that particles of the film material emitted from the target are attached to the workpiece. In the film forming processing section, a processing space in which a film is formed on the workpiece is formed by an adhesion prevention plate that surrounds an area including the target. This adhesion prevention plate plays the role of a shield that prevents particles of the film material emitted from the target from adhering to the inner surface of the chamber and diffusing into the chamber. In addition, there is also a film forming apparatus that forms a film by sputtering while heating the workpiece (see Patent Document 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 7144219 [Patent Document 2] Patent No. 6611666 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the above-mentioned film forming processing apparatus, the adhesion prevention plate provided in the film forming processing unit expands and contracts due to thermal expansion. When this expansion and contraction occurs, the film forming material attached to the adhesion prevention plate peels off and falls onto the rotating table. If the fallen film forming material remains on the rotating table, it becomes a source of contamination of the workpiece, causing product defects of the workpiece.

[0005] Such expansion and contraction of the adhesion prevention plate due to thermal expansion is likely to occur when the film formation process is completed, the device is stopped, and the temperature inside the chamber is lowered to room temperature, such as when performing maintenance. During the film formation process, the temperature is controlled to be constant by a heating unit installed in the turntable, but the temperature inside the chamber may fluctuate, and the film formation material may fall due to slight expansion and contraction of the adhesion prevention plate. For this reason, it is necessary to suppress the expansion and contraction of the adhesion prevention plate due to thermal expansion.

[0006] The present invention has been proposed to solve the above-mentioned problems, and has an object to provide a film forming apparatus capable of suppressing expansion and contraction of an adhesion prevention plate due to thermal expansion. [Means for solving the problem]

[0007] In order to achieve the above-mentioned object, the film forming apparatus of this embodiment comprises a chamber capable of creating a vacuum inside, a table provided within the chamber and supporting a workpiece, a film forming unit having a plasma generator that converts a gas introduced into the chamber into plasma and forms a film on the workpiece supported on the table, an adhesion prevention plate that is arranged to surround a processing space in which a film is formed on the workpiece by the film forming unit and prevents adhesion of film forming material to the inside of the chamber, a cooling block provided within the chamber and having a contact surface that directly contacts the adhesion prevention plate and cools the adhesion prevention plate by contacting the contact surface, and a flow path provided in the cooling block through which a cooling medium flows. Effect of the Invention

[0008] According to an embodiment of the present invention, it is possible to suppress expansion and contraction of the adhesion prevention plate due to thermal expansion, reduce peeling of the film forming material adhered to the adhesion prevention plate, and suppress adhesion of the peeled film forming material to the workpiece, thereby reducing the occurrence of product defects. [Brief description of the drawings]

[0009] [Figure 1] 1 is a partially perspective plan view showing a schematic configuration of a film forming apparatus according to an embodiment; [Diagram 2] 2 is a cross-sectional view taken along the line AB in FIG. 1, showing in detail the internal configuration of the film forming apparatus as viewed from the side. [Diagram 3] 2 is a cross-sectional view taken along the line AC in FIG. 1, showing in detail the internal configuration of the film forming apparatus as viewed from the side. [Figure 4] 1A is a top perspective view showing a workpiece to be film-formed, and an absorbing member and a tray on which the workpiece is placed, and FIG. [Diagram 5] 1A is a plan view showing an adhesion prevention plate and a cooling block, FIG. 1B is a side view seen from the α side of FIG. 1A, and FIG. 1C is a side view seen from the β side of FIG. [Figure 6] 1A is an exploded perspective view of the adhesion prevention plate and the cooling block as viewed from the top side, FIG. 1B is a perspective view thereof, and FIG. [Figure 7] 4 is a flowchart of a process performed by a film forming apparatus according to an embodiment. [Figure 8] 1A is a cross-sectional view showing an example of a layer structure of an LED, and FIG. 1B is an enlarged cross-sectional view of a buffer layer. [Figure 9] 11 is a vertical cross-sectional view (a cross-sectional view taken along the line EE in FIG. 10) showing a modified example of a film forming apparatus that does not use circulating transport. [Figure 10] 10 is a cross-sectional view of the film forming apparatus of FIG. 9 taken along the arrow DD. [Figure 11] FIG. 10 is a perspective view of a cooling block applied to FIG. 9. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] An embodiment of a film forming apparatus will be described with reference to the drawings. Note that the drawings are merely schematic illustrations of each member and each component, and do not accurately depict the dimensions, intervals, and the like. [overview] A film forming apparatus 1 shown in FIGS. 1 to 3 is an apparatus for forming a GaN (Gallium Nitride) film or an AlN (Aluminum Nitride) film on a workpiece 10, which is an object to be formed with a film, by sputtering.

[0011] The workpiece 10 on which the film is formed is, for example, a silicon (Si) wafer, a silicon carbide (SiC) wafer, a sapphire substrate, or a glass substrate. As shown in FIG. 4(A), the workpiece 10 in this embodiment is a circular plate. As described below, the workpiece 10 is placed on a tray 11 and transported. The tray 11 is a plate held by a rotating table 31. The workpiece 10 is placed on the tray 11 via an absorbing member 12, as shown in FIGS. 4(A) and (B).

[0012] 1, the film forming apparatus 1 includes a chamber 20, a transport section 30, a film forming section 40, an adhesion prevention plate 410, a cooling block 420, a film processing section 50, a surface processing section 60, a transfer section 70, and a control device 90. These will be described in detail below.

[0013] The film forming apparatus 1 is placed in a chamber 20, the inside of which can be evacuated, and while the workpiece 10 is being transported by a transport unit 30, various processes are performed by a film forming unit 40 which performs a film forming process on the workpiece 10, a film processing unit 50 which performs a chemical reaction process on the film formed by the film forming unit 40, and a surface processing unit 60 which processes the surface of the workpiece 10 before film formation or after film formation. The film forming apparatus 1 also has a transport unit 70 for carrying the workpiece 10 in and out of the chamber 20. Each of these units is controlled by a control device 90.

[0014] [Chamber] As shown in Fig. 2, the chamber 20 is a container capable of evacuating the inside. The chamber 20 has a cylindrical shape and is surrounded by a disk-shaped top surface 20a, a disk-shaped bottom surface 20b, and an annular side surface 20c. The top surface 20a is provided so as to be openable and closable for maintenance and the like. A cylindrical space is provided inside the chamber 20. A rotary table 31 for transporting the workpiece 10, which will be described later, is disposed in this cylindrical space.

[0015] The chamber 20 is provided with an exhaust port 21. The exhaust port 21 is connected to an exhaust unit 23. The exhaust unit 23 has piping, a pump, a valve, and the like (not shown). By exhausting air by the exhaust unit 23 through the exhaust port 21, the inside of the chamber 20 can be depressurized and made into a vacuum. The exhaust unit 23 is set to a vacuum level of, for example, 10° C. in order to keep the oxygen concentration low. -4 Evacuate until the pressure reaches 1 Pa.

[0016] 1, the chamber 20 is provided with a loading / unloading port 24 for loading and unloading the workpiece 10. The loading / unloading port 24 is provided at one location on the side of the chamber 20, and a transfer unit 70, which will be described later, is connected to this position.

[0017] [Transport section] 1 to 3, the transport section 30 has a rotary table 31, a motor 32, a heat insulating section 33, a heating section 34, a rotary connection section 35, and a heat shielding section 36. The transport section 30 is provided in the chamber 20, holds a plurality of workpieces 10, and circulates and transports the workpieces 10 along a transport path L which is a circumferential trajectory. The transport section 30 also heats the workpieces 10 with the heating section 34.

[0018] (Rotary table) The rotating table 31 is a table provided in the chamber 20 and supports the workpiece 10. The rotating table 31 is a disk-shaped member arranged in the chamber 20, and is expanded so as not to come into contact with the inside of the side surface 20c. The rotating table 31 circulates and transports the workpiece 10 along the transport path L. The rotating table 31 is supported by inserting a cylindrical rotating shaft 311 coaxial with the rotating table 31 into an insertion hole 31a provided in the center of the rotating table 31 via a fastening member 31b. The inside of the rotating shaft 311 is a hollow atmospheric pressure space, and a circular plate 311b is fixed so as to cover the central hole 311a, which is an open end. The rotating shaft 311 also protrudes to the outside through a through hole 20d provided in the bottom surface 20b of the chamber 20, and is rotatably supported by a fastening member 20e fastened to the bottom surface 20b so as to be airtight.

[0019] In the present embodiment, the film forming apparatus 1 is installed so that the rotation axis 311 of the turntable 31 is in the vertical direction, and the direction parallel to the rotation axis 311 is the up-down direction. In the following description, movement in the direction parallel to the rotation axis 311 is referred to as up-down movement or lifting and lowering. However, the installation direction of the film forming apparatus 1 is not limited to this.

[0020] (Motor) The motor 32 is disposed outside the chamber 20 and is a drive source that rotates the rotary shaft 311 via a coupling member (not shown) to continuously rotate the rotary table 31 at a predetermined rotation speed. The rotary table 31 rotates at a speed of, for example, 1 to 150 rpm.

[0021] The workpiece 10 is placed on a tray 11 and transported by a rotating table 31. The tray 11 is a plate held by the rotating table 31. As shown in Figs. 4(A) and (B), the tray 11 in this embodiment is, for example, a horizontally elongated hexagonal quartz plate. In the center of the tray 11, an absorbing member 12 for holding the workpiece 10 is fitted into a hole 11a. A step for supporting the absorbing member 12 is provided on the inner edge of the hole 11a. The workpiece 10 is placed on the tray 11 via the absorbing member 12.

[0022] As shown in Fig. 4(B), positioning holes 11b are formed on the bottom surface of the tray 11. Two positioning holes 11b are formed, one on each side near the central hole 11a. Note that cases where the workpiece 10 is held, transferred, conveyed, carried in, or carried out include cases where the workpiece 10 is held, transferred, conveyed, carried in, or carried out via other members such as the tray 11 or the absorbing member 12.

[0023] The absorbing member 12 is a member that is heated by receiving electromagnetic waves from the heating unit 34, suppresses heat dissipation from the workpiece 10 heated by the heating unit 34, and suppresses a decrease in temperature of the workpiece 10. The absorbing member 12 in this embodiment is a circular plate having a circular recess on its upper surface for placing the workpiece 10. The absorbing member 12 is fitted into the hole 11a of the tray 11 so that its upper and lower surfaces are exposed.

[0024] The absorbing member 12 is made of a material that absorbs electromagnetic waves of the wavelength emitted by the heating unit 34. The absorbing member 12 is a plate-shaped member. Materials with low thermal conductivity and excellent heat resistance, such as silicon carbide (SiC), carbon graphite, and glassy carbon, can be used as the absorbing member 12. A heat-resistant hard member with a black surface may be used as the absorbing member 12. The color does not need to be limited to black. In other words, the absorbing member 12 may be a member that is partially or entirely coated with paint that absorbs electromagnetic waves of the wavelength emitted by the heating unit 34, or a member that is partially made of a material that absorbs electromagnetic waves of the wavelength emitted by the heating unit 34. If the workpiece 10 can be heated to a desired temperature by the heating unit 34 alone, the absorbing member 12 is not essential.

[0025] As shown in Fig. 1, the turntable 31 is provided with a film-forming area FA where a plurality of workpieces 10 are formed. As shown by the two-dot chain line in Fig. 1, the film-forming area FA is an area other than the rotation axis 311 of the turntable 31 in a plan view, and is an annular area facing the film-forming unit 40 and the film processing unit 50. In the film-forming area FA, holding areas HA where the individual workpieces 10 are held are provided at equal intervals in the circumferential direction.

[0026] As shown in Figs. 1 to 3, the holding area HA is formed with a holding hole 31c having an inner edge with a step into which the outer edge of the tray 11 fits. Although not shown, a pair of positioning pins are provided on the bottom surface of the holding hole 31c in a plan view, sandwiching a heating unit 34 described later. The tray 11 is positioned by fitting the pair of positioning pins into the positioning holes 11b, and is placed in the holding hole 31c. In this way, the tray 11 with the workpieces 10 mounted thereon is held in the holding area HA.

[0027] 1, six holding areas HA are arranged at intervals of 60° on the rotating table 31. In other words, the film forming apparatus 1 can simultaneously form films on a plurality of workpieces 10 held in a plurality of holding areas HA, and therefore has very high productivity.

[0028] (Insulation section) As shown in Figs. 2 and 3, the heat insulating section 33 is a plate made of a heat insulating material and is fixed to the holding area HA. ​​In this embodiment, the heat insulating section 33 is fitted into the bottom surface of the holding hole 31c. For example, ceramics is used as the heat insulating section 33. The heat insulating section 33 has the same shape as the heating section 34 and is at least the same size as the heating section 34. In other words, the heat insulating section 33 only needs to be larger than or equal to the heating section 34 so that the entire heating section 34 overlapping the heat insulating section 33 fits within the outer edge of the heat insulating section 33 in a plan view.

[0029] (heating part) The heating unit 34 is a heater that generates heat by passing electricity through it. The heater may generate heat by resistance heating, electromagnetic induction heating, or an LED light source. The heating unit 34 is a circular plate and is supported on the heat insulating unit 33. As a result, the heating unit 34 is disposed between the turntable 31 and the workpiece 10 in the holding area HA, and the heat insulating unit 33 is disposed between the heating unit 34 and the turntable 31. The heating unit 34 may have a size at least large enough to accommodate the workpiece 10 on the absorbing member 12 or the workpiece 10 on the tray 11. For this reason, the heating unit 34 does not necessarily have to be large enough to include the tray 11. The heat insulating unit 33 and the heating unit 34 as described above are each disposed within the holding area HA.

[0030] When the workpiece 10 is placed on the holding area HA of the turntable 31, the upper surface of the heating part 34 is arranged to correspond to the lower side of the absorbing member 12. That is, as shown in Fig. 2, the heat insulating part 33, the heating part 34, the absorbing member 12, and the workpiece 10 are arranged in this order from the bottom of the turntable 31 so as to overlap each other.

[0031] The heat insulating section 33, which has the same shape as the heating section 34 and is at least as large as the heating section 34, can prevent the heat generated from the heating section 34 from escaping to the turntable 31, which can cause damage (deformation, etc.) to the turntable 31. It can also prevent heat from radiating from below the turntable 31. The heating section 34 heats the workpiece 10 via the absorbing member 12 of the tray 11. However, the absorbing member 12 may be omitted and the heating section 34 may be configured to come into contact with the workpiece 10. In other words, the heating section 34 may come into contact with the workpiece 10 to directly heat it, or may heat it indirectly via another member.

[0032] (Rotary connection) The rotary connection part 35 is a connector for electrically connecting the heating part 34, which is circulated and transported along a circular trajectory together with the workpiece 10, to a power source. The rotary connection part 35 in this embodiment is a slip ring having a rotating electrode part 351 and a stationary electrode part 352. Note that a rotary connector can also be used as the rotary connection part 35.

[0033] More specifically, the rotating electrode unit 351 has a plurality of conductive ring electrodes 351a arranged coaxially on the rotating shaft 311 outside the chamber 20. Each ring electrode 351a is connected to the heating unit 34 by a cable 351b (positive electrode wire, negative electrode wire). The cable 351b from each ring electrode 351a passes through a hole provided in the rotating shaft 311, passes through the inside of the rotating shaft 311 and the center of the plate 311b, and reaches the heating unit 34. As a result, each ring electrode 351a and the cable 351b rotate together with the rotating shaft 311.

[0034] The stationary electrode unit 352 is a component in which a plurality of conductive brush electrodes 352a are fixed at positions in contact with the respective ring electrodes 351a, independently of the rotating shaft 311. The brush electrodes 352a are connected to the control device 90 via cables 352b, and power is supplied to and controlled by the control device 90. In other words, power is applied or stopped to the ring electrode 351a via the brush electrodes 352a, and the temperature of the heating unit 34 is increased or decreased.

[0035] A part of the brush electrode 352a is pressed against the outer periphery of the ring electrode 351a, forming a sliding contact point. This makes the rotating electrode part 351 and the stationary electrode part 352 conductive, and even if the rotating electrode part 351 rotates together with the rotating shaft 311, the ring electrode 351a is always maintained in contact with the brush electrode 352a, so that power can be transmitted to the heating part 34.

[0036] The reason why the rotating connection part 35, which is a slip ring, is provided outside the chamber 20 is to prevent vacuum discharge at the sliding contact point between the brush electrode 352a and the ring electrode 351a. Although simplified in Fig. 2, a pair of cables 351b, 352b connected to the ring electrode 351a and the brush electrode 352a is provided for each heating part 34, and the temperature of each heating part 34 can be controlled individually.

[0037] (Heat shielding section) The heat shield 36 is disposed along the film formation area FA, at a distance from the turntable 31, on the opposite side of the turntable 31 from the film formation area FA (including the processing space 59 and the processing space 64) facing each processing unit. In other words, the heat shield 36 is disposed so as to cover the lower surface of the turntable 31 at a distance. The heat shield 36 has a plurality of heat shield plates 36a. The heat shield plates 36a are horizontal ring-shaped flat metal plates. The heat shield plates 36a are disposed in a stack at intervals vertically, and are supported and fixed to the bottom surface 20b of the chamber 20 by support legs 36b.

[0038] In this way, by arranging a plurality of heat shields 36a in a stacked manner from a position close to the rotary table 31 to a position away from the rotary table 31, the radiant heat from the heating unit 34 can be gradually reduced in a vacuum, and the heat radiation to the bottom surface 20b of the chamber 20 can be suppressed. By suppressing the heat radiation from the bottom surface 20b of the chamber 20, damage caused by heat to the inner wall surface of the bottom surface 20b of the chamber 20, the bearing of the rotating shaft 311, etc. can be prevented. By preventing the outflow of heat, there is also a heat retention effect, and the workpiece 10 can be maintained at a high temperature. Furthermore, the desired temperature can be maintained with less power. In addition to the heat shields 36a, a reflector can be provided to prevent the light emitted from the heating unit 34 from hitting the bottom surface 20b of the chamber 20. In order to obtain a similar light reflection effect, the surface of the heat shields 36a can be gold-plated.

[0039] [Film forming section] The film forming unit 40 generates plasma and exposes a target 42 made of a film forming material to the plasma. In this manner, the film forming unit 40 deposits particles (hereinafter referred to as sputter particles) constituting the target 42, which are knocked out by colliding ions contained in the plasma with the target 42, on the workpiece 10 to form a film. The film forming unit 40 has a plasma generator P1 that converts a sputter gas G1 introduced between the target 42 made of a film forming material and the rotating table 31 into plasma.

[0040] As shown in FIGS. 2 and 3, the plasma generator P1 is composed of a sputtering source composed of a target 42, a backing plate 43, and an electrode 44, a power supply unit 46, and a sputtering gas introduction unit 49.

[0041] The target 42 is a plate-like member made of a film-forming material that is deposited on the workpiece 10 to form a film. The target 42 is provided at a distance on the transport path L of the workpiece 10 placed on the turntable 31. The surface of the target 42 is held on the top surface 20a of the chamber 20 so as to face the workpiece 10 placed on the turntable 31. For example, three targets 42 are provided. The three targets 42 are provided at positions aligned on the vertices of a triangle in a plan view.

[0042] The backing plate 43 is a support member that holds the targets 42. This backing plate 43 holds each target 42 individually. The electrode 44 is a conductive member for applying power to each target 42 individually from outside the chamber 20, and is electrically connected to the targets 42. The power applied to each target 42 can be changed individually. In addition, the sputtering source is appropriately equipped with a magnet, a cooling mechanism, etc. as necessary.

[0043] The power supply unit 46 is, for example, a DC power supply that applies a high voltage, and is electrically connected to the electrode 44. The power supply unit 46 applies power to the target 42 through the electrode 44. The rotary table 31 has the same potential as the grounded chamber 20, and a potential difference is generated by applying a high voltage to the target 42 side.

[0044] 2 and 3, the sputtering gas introduction part 49 introduces the sputtering gas G1 into the chamber 20. The sputtering gas introduction part 49 has a supply source of the sputtering gas G1 such as a cylinder (not shown), a pipe 48, and a gas introduction port 47. The pipe 48 is connected to the supply source of the sputtering gas G1, airtightly penetrates the chamber 20, and extends into the interior of the chamber 20, with its end opening as the gas introduction port 47. The sputtering gas introduction part 49 of this embodiment introduces the sputtering gas G1 into the processing space 41 so that the pressure in the processing space 41 is, for example, 0.3 Pa or more and 1.0 Pa or less.

[0045] The gas inlet 47 opens between the turntable 31 and the target 42, and introduces a sputtering gas G1 for film formation into a processing space 41 formed between the turntable 31 and the target 42. A rare gas can be used as the sputtering gas G1, and argon (Ar) gas or the like is preferable. The sputtering gas G1 can be, for example, argon (Ar) gas alone.

[0046] In this film forming section 40, when sputtering gas G1 is introduced from sputtering gas inlet 49 and power supply 46 applies a high voltage to target 42 through electrode 44, sputtering gas G1 introduced into processing space 41 formed between turntable 31 and target 42 turns into plasma, generating active species such as ions. The ions in the plasma collide with target 42 and knock out sputter particles.

[0047] The workpiece 10 passes through this processing space 41 while being circulated and transported by the turntable 31. The sputtered particles are deposited on the workpiece 10 as the workpiece 10 passes through the processing space 41, and a film made of the sputtered particles is formed on the workpiece 10. The workpiece 10 is circulated and transported by the turntable 31, and is subjected to a film forming process by repeatedly passing through this processing space 41. The thickness of the film deposited each time it passes through the film forming section 40 depends on the processing rate of the film processing section 50, but can be, for example, a thin film at the 1 to 2 atom level (5 nm or less). By circulating and transporting the workpiece 10 multiple times, the thickness of the film increases, and a film of a predetermined thickness is formed on the workpiece 10.

[0048] The multiple film forming units 40 selectively deposit the film forming materials to form a film consisting of multiple layers of the film forming materials. In particular, in this embodiment, sputtering sources corresponding to different types of film forming materials are included, and a film consisting of multiple layers of the film forming materials is formed by selectively depositing the film forming materials. Including sputtering sources corresponding to different types of film forming materials includes cases in which the film forming materials of all the film forming units 40 are different, and cases in which the film forming materials are common to the multiple film forming units 40 but different from the others. Selectively depositing film forming materials one by one means that while a film forming unit 40 of any one type of film forming material forms a film, the film forming units 40 of the other film forming materials do not form a film.

[0049] 1, two film forming units 40 are arranged, and the film forming material constituting the target 42 of one of the film forming units 40 is a material containing Ga and GaN, and the target 42 serves as a supply source of sputtered particles containing Ga atoms to be deposited on the workpiece 10. The target 42 contains GaN and incomplete GaN lacking nitrogen, that is, Ga atoms lacking bonds with N (nitrogen).

[0050] The film forming material constituting the target 42 of the other film forming unit 40 is a material containing Al, and the target 42 serves as a supply source of sputtering particles containing Al atoms to be deposited on the workpiece 10. Note that as long as the sputtering target 42 is capable of supplying sputtering particles containing Ga atoms and sputtering particles containing Al atoms, it is permissible for the target 42 to contain elements other than Ga, Al, and N (nitrogen).

[0051] In order to distinguish between the two film formation units 40, the film formation unit 40 having a target 42 made of a material containing Ga and GaN is referred to as film formation unit 40A (GaN film formation unit), and the film formation unit 40 having a target 42 made of a material containing Al is referred to as film formation unit 40B (Al film formation unit).

[0052] [Anti-adhesion plate] The adhesion prevention plate 410 is disposed so as to surround the processing space 41 in which the film is formed on the workpiece 10 by the film forming unit 40, and prevents the deposition material from adhering to the inside of the chamber 20. As shown in Figs. 5(A) to 5(C), the adhesion prevention plate 410 has a body part 411, an extension part 412, a heat transfer part 413, and a shielding part 414. The body part 411 is a cylindrical member that surrounds the processing space 41 including the target 42. The extension part 412 is a plate body whose area is extended in a direction parallel to the rotation plane (surface of the turntable 31) of the turntable 31 at the outer edge of one end (upper end) of the body part 411 (see Figs. 2 and 3). The outer shape of the extension part 412 is a sector whose width increases from the rotation center of the turntable 31 toward the outer periphery. At least the arc part of the sector of the extension part 412 is shaped to fit the inner wall of the chamber 20.

[0053] The lower end of the adhesion prevention plate 410 faces the mounting surface of the turntable 31 on which the workpiece 10 is placed, with a gap therebetween through which the workpiece 10 placed on the turntable 31 passes. The adhesion prevention plate 410 separates a processing space 41 in which the workpiece 10 is processed by the film forming unit 40. That is, the film forming unit 40 has a processing space 41 smaller than the chamber 20. The adhesion prevention plate 410 suppresses the sputtering gas G1 and film forming material used in the film forming unit 40 from diffusing into the chamber 20. In the film forming unit 40, it is only necessary to adjust the pressure in the processing space 41, which is partitioned to be smaller than the chamber 20, and therefore pressure adjustment can be easily performed, and plasma discharge can be stabilized.

[0054] 2 and 3, the protection plate 410 is not in contact with the top surface 20a, so that a gap is formed between the top of the protection plate 410 and the top surface 20a to prevent collision when the top surface 20a is opened or closed. However, since an extension part 412 is provided on the top of the protection plate 410, the narrow space formed between the top of the protection plate 410 and the inner wall of the top surface 20a of the chamber 20 is expanded in the horizontal direction, so that the film forming material is unlikely to leak out of the processing space 41. Furthermore, a partition such as a partition wall may be provided near the side surface of the protection plate 410 to reduce leakage of the sputtering gas G1 and the film forming material.

[0055] The heat transfer section 413 is a plate body in which the outer edge of the other end (lower end) of the body section 411 is expanded in a direction parallel to the rotation plane (surface of the turntable 31) of the turntable 31. That is, the heat transfer section 413 whose area is expanded outward is provided at the bottom of the adhesion prevention plate 410. The outer shape of the heat transfer section 413 is a sector whose width increases from the rotation center of the turntable 31 toward the outer periphery (see FIGS. 6(A) to (C)). At least the arc portion of the sector of the heat transfer section 413 is shaped to fit along the inner wall of the chamber 20.

[0056] 2 and 3, the heat transfer section 413 is not in contact with the turntable 31, and therefore a gap is formed between the lower part of the adhesion-prevention plate 410 and the turntable 31 to allow rotation of the turntable 31. However, since the heat transfer section 413 that extends outward is provided at the lower part of the adhesion-prevention plate 410, the narrow space formed between the lower part of the adhesion-prevention plate 410 and the surface of the turntable 31 is expanded in the horizontal direction, and the film forming material is unlikely to leak out of the processing space 41.

[0057] 1 and 5(A), the shielding portion 414 is a plate that narrows the opening 411a at the lower end of the body portion 411 to a predetermined range. The shielding portion 414 has a width the same as the width of the work 10 (maximum length in the short side direction) in a plan view, and protrudes inward from the lower end of the body portion 411 so as to form an arc-shaped opening 411a along the conveying path L.

[0058] The adhesion prevention plate 410 is detachably provided in the chamber 20. More specifically, as shown in FIG. 2 and FIG. 3, the bottom of the adhesion prevention plate 410, which is located outside the outer periphery of the rotary table 31, is supported by a cooling block 420, which will be described later. As shown in FIG. 1, the inner periphery of the adhesion prevention plate 410 is attached to a ring 415 arranged above the center of the rotary table 31 via a fixing plate 415a by a fastening member such as a bolt. The ring 415 is fixed in the chamber 20 by a plurality of support parts 416. That is, one end of each support part 416 is fixed to the ring 415, and the other end extends radially toward the side surface 20c of the chamber 20 and is fixed to the inner wall surface of the side surface 20c, thereby supporting the ring 415 in the chamber 20. Note that in FIG. 2 and FIG. 3, the support parts 416 are indicated by dashed lines.

[0059] [Cooling block] As shown in FIG. 2 and FIG. 3, the cooling block 420 is provided in the chamber 20 (see FIG. 2 and FIG. 3), and is a block-shaped member for cooling the adhesion prevention plate 410. As shown in FIG. 5 and FIG. 6, the cooling block 420 is a solid rectangular metal. For example, aluminum having good thermal conductivity can be used as the material of the cooling block 420. As shown in FIG. 1 to FIG. 3, the cooling block 420 is disposed in the space between the outer periphery of the turntable 31 and the inner wall of the side surface 20c of the chamber 20. A plurality of cooling blocks 420 are disposed. The cooling blocks 420 of this embodiment are disposed so as to be aligned along the space between the outer periphery of the turntable 31 and the inner wall of the side surface 20c of the chamber 20. In this embodiment, two cooling blocks 420 are aligned for one adhesion prevention plate 410. Also, as shown in FIG. 1, each cooling block 420 is fan-shaped in a plan view. More specifically, the cooling block 420 on the inner wall side of the side surface 20c of the chamber 20 has an arc shape that follows the inner wall of the side surface 20c. Also, the cooling block 420 on the turntable 31 side has an arc shape that follows the outer diameter of the turntable 31. That is, each cooling block 420 has two arc-shaped side surfaces.

[0060] The cooling block 420 has a contact surface 421 and a flow path 422. The contact surface 421 is in direct contact with the adhesion prevention plate 410. The cooling block 420 cools the adhesion prevention plate 410 by contacting the contact surface 421. That is, the cooling block 420 releases heat from the adhesion prevention plate 410 to the outside of the chamber 20. The contact point of the contact surface 421 is the bottom of the adhesion prevention plate 410. More specifically, the contact surface 421 is the upper surface of the cooling block 420, and is fixed by a fastener such as a bolt so as to contact the heat transfer part 413 of the adhesion prevention plate 410. Note that the fastening is not limited to the fastening by a fastener, and the heat transfer part 413 of the adhesion prevention plate 410 may simply be in contact with the contact surface 421. The bottom surface of the cooling block 420 is supported by the bottom surface 20b of the chamber 20.

[0061] The flow path 422 is a flow path through which the cooling medium flows. As shown in FIG. 5(B), the flow path 422 is provided near the contact surface 421, has a passage parallel to the contact surface 421, and both ends of the passage communicate with an inlet 422a and an outlet 422b provided at the bottom of the cooling block 420. As shown in FIG. 2 and FIG. 3, one of the inlets 422a of the two cooling blocks 420 is connected to a cooling device 423 that supplies a cooled cooling medium through a joint 422c and a pipe 422d provided outside the chamber 20, while maintaining the inside of the chamber 20 airtight with a sealing member such as an O-ring. The joint 422c and the cooling block 420 are integrally formed. A sealing member is provided around the joint 422c on the bottom surface of the cooling block 420, and the cooling block 420 and the bottom surface 20b of the chamber 20 are in contact with each other through the sealing member. A through hole 22 is provided in the bottom surface 20b of the chamber 20, and a joint 422c is inserted into the through hole 22, a part of which is exposed to the outside of the chamber 20, and a pipe 422d is connected to the part. As a result, the joint between the joint 422c and the pipe 422d is on the atmospheric side. The cooling device 423 of this embodiment uses water as a cooling medium. As the cooling device 423, for example, a chiller device that cools with a cooler while circulating a cooling medium such as cooling water can be used.

[0062] 6, adjacent outlets 422b and inlets 422a of two cooling blocks 420 are connected to each other via joints 422c and piping 422d provided outside the chamber 20 so that the cooling medium can flow between them while the inside of the chamber 20 is kept airtight by a sealing member such as an O-ring. That is, the cooling medium discharged from the flow path 422 of one cooling block 420 flows into the other cooling block 420. Furthermore, the other outlet 422b of the two cooling blocks 420 is connected to a cooling device 423 via joints 422c and piping 422d provided outside the chamber 20 while the inside of the chamber 20 is kept airtight by a sealing member such as an O-ring.

[0063] As a result, the cooling medium passes through the cooling block 420, and absorbs heat from the adhesion prevention plate 410, is cooled by the cooling device 423, and returns to the cooling block 420, where it again absorbs heat from the adhesion prevention plate 410. In this manner, the cooling medium circulates through the cooling block 420, enabling continuous cooling. The pipe 422d is provided outside the chamber 20 via the joint 422c, and is therefore not exposed to the heat inside the chamber 20.

[0064] [Membrane processing section] The film processing unit 50 generates an inductively coupled plasma in a processing space 59 to which a process gas G2 is introduced, and generates a compound film by chemically reacting chemical species in the plasma with a film deposited on the workpiece 10 by the film forming unit 40. As shown in Fig. 1, the film processing unit 50 is disposed in a section other than the section in which the film forming unit 40 is disposed in the chamber 20. In other words, the film processing unit 50 has a processing space 59 that is smaller than the chamber 20 and is isolated from the processing space 41.

[0065] The process gas G2 introduced contains, for example, oxygen or nitrogen. The process gas G2 may contain an inert gas such as argon gas, in addition to oxygen gas or nitrogen gas. The process gas G2 in this embodiment is a gas containing nitrogen. The film processing unit 50 in this embodiment is a nitriding processing unit that generates an inductively coupled plasma in a processing space 59 into which the process gas G2 containing nitrogen gas is introduced, and generates a nitride film by chemically reacting nitrogen atoms in the plasma with the film deposited on the workpiece 10 by the film forming unit 40.

[0066] As shown in FIG. 2, the film processing section 50 has a plasma generator P2 that is composed of a cylindrical body 51, a window member 52, an antenna 53, an RF power source 54, a matching box 55, and a process gas introduction section 58.

[0067] 1 and 2, the cylindrical body 51 has a cylindrical shape and has openings on both ends. The cylindrical body 51 is fitted into the top surface 20a of the chamber 20 so that one opening faces away from the turntable 31 and protrudes into the internal space of the chamber 20. The cylindrical body 51 is made of the same material as the turntable 31.

[0068] A window member 52 is provided inside the cylinder of the cylindrical body 51 so as to close the opening of the cylindrical body 51. A space surrounded by the upper surface of the turntable 31, the inside of the opening at the end of the cylindrical body 51 protruding close to the turntable 31, and the window member 52 becomes a processing space 59 in the film processing section 50. A process gas G2 containing nitrogen gas is introduced into the processing space 59 and turned into plasma. The workpiece 10, which is circulated and transported by the turntable 31, passes repeatedly through this processing space 59, thereby performing a nitriding process.

[0069] At this time, since the processing space 59 is separated from the space of the chamber 20 by the cylindrical body 51, the process gas G2 is prevented from diffusing into the chamber 20. Since it is only necessary to adjust the pressure in the processing space 59 thus separated, the pressure can be easily adjusted and the plasma discharge can be stabilized.

[0070] The window member 52 is a flat plate made of a dielectric material such as quartz having a shape similar to the horizontal cross section of the cylindrical body 51. The window member 52 is provided to close the opening of the cylindrical body 51, and serves as a partition between a processing space 59 into which the process gas G2 containing nitrogen gas in the chamber 20 is introduced and the inside of the cylindrical body 51. The window member 52 may be made of a dielectric material such as alumina, or a semiconductor material such as silicon.

[0071] The antenna 53 is a conductor wound into a coil shape, and is disposed in the internal space of the cylindrical body 51 isolated from the processing space 59 in the chamber 20 by the window member 52, and generates an electric field by passing an alternating current through it. It is preferable that the antenna 53 is disposed near the window member 52 so that the electric field generated by the antenna 53 is efficiently introduced into the processing space 59 through the window member 52. An RF power supply 54 that applies a high frequency voltage is connected to the antenna 53. A matching box 55, which is a matching circuit, is connected in series to the output side of the RF power supply 54. The matching box 55 stabilizes the plasma discharge by matching the impedance on the input side and the output side.

[0072] 2, the process gas introduction part 58 introduces the process gas G2 into the processing space 59. The process gas introduction part 58 has a supply source of the process gas G2 such as a cylinder (not shown), a pipe 57, and a gas introduction port 56. The pipe 57 is connected to the supply source of the process gas G2, penetrates the chamber 20 while airtightly sealing it, and extends into the interior of the chamber 20, with its end opening as the gas introduction port 56.

[0073] The gas inlet 56 opens into a processing space 59 between the window member 52 and the rotary table 31, and introduces a process gas G2.

[0074] In the film processing section 50, a high-frequency voltage is applied to the antenna 53 from the RF power supply 54. This causes a high-frequency current to flow through the antenna 53, generating an electric field due to electromagnetic induction. The electric field is generated in the processing space 59 through the window member 52, and an inductively coupled plasma is generated in the process gas G2. At this time, chemical species of nitrogen containing nitrogen atoms are generated, and by colliding with the film on the workpiece 10, they bond with the atoms that make up the film. As a result, the film on the workpiece is nitrided, and a nitride film is formed as a compound film.

[0075] The reason why the film forming unit 40A uses a material containing GaN as the target 42 and further provides a film processing unit 50 that performs nitridation is as follows: Ga has a low melting point and is in a liquid state at room temperature and normal pressure, so it is necessary to make it contain nitrogen (N) in order to make it a solid target 42. For this reason, it is possible to simply increase the nitrogen content of the target 42 and form a film by sputtering the target 42 alone.

[0076] Here, in order to improve the deposition rate, DC discharge sputtering is more preferable than RF discharge. However, if the target 42 contains a large amount of nitrogen, the surface becomes an insulator. In the case of the target 42 with an insulator surface, DC discharge may not occur.

[0077] Therefore, there is a limit to the amount of nitrogen that can be contained in the GaN target 42, and the nitridation of Ga in the target 42 remains insufficient. In other words, the GaN-containing target 42 contains Ga atoms that are deficient in bonding with N (nitrogen) atoms.

[0078] If the nitrogen content is low and there are nitrogen defects in the formed GaN film, the crystallinity of the film will be poor and the flatness will be impaired, so it is necessary to compensate for the lack of nitrogen. Therefore, it is possible to add nitrogen gas to the sputtering gas G1 introduced into the film forming unit 40 and perform sputtering, but there is a risk that the surface of the target 42 will be nitrided and become an insulator. Therefore, the film forming unit 40A cannot add a sufficient amount of nitrogen gas to the sputtering gas G1 to compensate for the lack of nitrogen.

[0079] Therefore, in order to compensate for the lack of nitrogen in the GaN film formed by the film forming unit 40A, after the film is formed by the film forming unit 40A, nitridation is further performed by the film processing unit 50. As a result of such nitridation treatment during film formation, the nitrogen content of the film on the workpiece 10 can be increased, and a GaN film without nitrogen defects can be formed.

[0080] [Surface treatment section] The surface treatment section 60 treats the surface of the workpiece 10 being circulated and transported by the turntable 31 and the surface of the film deposited by the film deposition section 40. The treatments performed by the surface treatment section 60 include removing oxide films from the surface of the workpiece 10 before the film is deposited by the film deposition section 40, removing organic matter, and flattening the surface of the film being formed on the workpiece.

[0081] The film in the process of being formed on the workpiece 10 refers to a film that is being formed on the workpiece 10 until it reaches the desired film thickness, specifically, a compound film on the workpiece 10 that has been processed by the film processing unit 50, or a film on the workpiece 10 that has been formed by the film forming unit 40.

[0082] As shown in FIG. 1, the conveying unit 30 rotates as indicated by the arrows drawn along the various parts of FIG. 1, and circulates and conveys the workpiece 10 so that it passes through the film forming unit 40, the film processing unit 50, and the surface processing unit 60 in this order. As a result, the surface processing unit 60 can irradiate ions onto the compound film on the workpiece 10 that has been processed by the film processing unit 50 to process the surface. Alternatively, when the film forming unit 40, the surface processing unit 60, and the film processing unit 50 are arranged in this order in the conveying direction of the workpiece 10, the conveying unit 30 circulates and conveys the workpiece 10 so that it passes through the film forming unit 40, the surface processing unit 60, and the film processing unit 50 in this order, so that the surface processing unit 60 can irradiate ions onto the film on the workpiece 10 formed by the film forming unit 40 to process the surface.

[0083] In this way, it is possible to set what type of film is surface-treated by the surface treatment unit 60 by arranging the film-forming unit 40, surface treatment unit 60, and film treatment unit 50 in the order of arrangement or combination of arrangements along the conveying direction of the workpiece 10. For example, by arranging the film-forming unit 40, surface treatment unit 60, film treatment unit 50, and surface treatment unit 60 in this order and conveying the workpiece 10 in this order, it is possible to treat the surface of the film deposited by the film-forming unit 40 and to treat the surface of the film after the film-treatment during one revolution.

[0084] The surface treatment section 60 is disposed in a section of the chamber 20 other than the sections in which the film formation section 40 and the film treatment section 50 are disposed. As shown in FIG. 3, the surface treatment section 60 includes a plasma generator P3 including a cylindrical electrode 61, a shield 62, a process gas introduction section 65, and an RF power supply 66.

[0085] 1 and 3, the cylindrical electrode 61 is a box-shaped, rectangular cylindrical electrode provided from the upper portion of the chamber 20 to the inside thereof. The shape of the cylindrical electrode 61 is not particularly limited, but in this embodiment, it is substantially fan-shaped in a plan view. The cylindrical electrode 61 has an opening 61a at its bottom, and the other end is closed. The outer edge of the opening 61a, i.e., the lower end of the cylindrical electrode 61, faces the upper surface of the workpiece 10 on the rotating table 31 with a small gap therebetween.

[0086] Therefore, the cylindrical electrode 61 is attached to an opening 21a provided in a top surface 20a of the chamber 20 via an insulating member 61c so that one end having an opening 61a faces the turntable 31. The side wall of the cylindrical electrode 61 extends into the chamber 20.

[0087] An outwardly projecting flange 61b is provided on the end of the cylindrical electrode 61 opposite the opening 61a. An insulating member 61c is fixed between the flange 61b and the periphery of the opening 21a of the chamber 20 to keep the inside of the chamber 20 airtight. The insulating member 61c may be made of any material as long as it has insulating properties, and may be made of, for example, PTFE (polytetrafluoroethylene) or other material.

[0088] The opening 61a of the cylindrical electrode 61 is disposed at a position facing the transport path L of the turntable 31. The turntable 31, which serves as the transport unit 30, transports the tray 11 carrying the workpieces 10 and passes through a position facing the opening 61a. Note that the opening 61a of the cylindrical electrode 61 is larger than the size of the tray 11 in the radial direction of the turntable 31.

[0089] As described above, the cylindrical electrode 61 penetrates the opening 21a of the chamber 20, and a portion of it is exposed to the outside of the chamber 20. The portion of the cylindrical electrode 61 exposed to the outside of the chamber 20 is covered by a housing 61d, as shown in Fig. 3. The housing 61d together with the insulating member 61c keeps the space inside the chamber 20 airtight. The portion of the cylindrical electrode 61 located inside the chamber 20, i.e., the periphery of the side wall, is covered by a shield 62.

[0090] The shield 62 is a sector-shaped rectangular cylinder coaxial with the cylindrical electrode 61 and is larger than the cylindrical electrode 61. The shield 62 is connected to the chamber 20. Specifically, the shield 62 stands upright from the edge of the opening 21a of the chamber 20, and the end portion extending toward the inside of the chamber 20 is located at the same height as the opening 61a of the cylindrical electrode 61. The shield 62 acts as a cathode like the chamber 20, so it is preferable that the shield 62 is made of a conductive metal member with low electrical resistance. The shield 62 may be molded integrally with the chamber 20, or may be attached to the chamber 20 using a fixing metal fitting or the like.

[0091] The shield 62 is provided to stably generate plasma in the cylindrical electrode 61. Each side wall of the shield 62 is provided to extend approximately parallel to each side wall of the cylindrical electrode 61 with a predetermined gap therebetween. If the gap is too large, the capacitance becomes small and the plasma generated in the cylindrical electrode 61 enters the gap, so it is desirable that the gap is as small as possible. However, if the gap is too small, the capacitance between the cylindrical electrode 61 and the shield 62 becomes large, which is not preferable. The size of the gap should be appropriately set according to the capacitance required for generating plasma. Note that FIG. 3 shows only two side wall surfaces extending in the radial direction of the shield 62 and the cylindrical electrode 61, but a gap of the same size as the side wall surfaces in the radial direction is provided between the two side wall surfaces extending in the circumferential direction of the shield 62 and the cylindrical electrode 61.

[0092] Further, a process gas introduction section 65 is connected to the cylindrical electrode 61. In addition to piping, the process gas introduction section 65 has a gas supply source of the process gas G3, a pump, a valve, etc. (not shown). The process gas G3 is introduced into the cylindrical electrode 61 by the process gas introduction section 65. The process gas G3 can be appropriately changed depending on the purpose of the process. For example, the process gas G3 may contain an inert gas such as argon gas, oxygen gas, or nitrogen gas, or may contain oxygen gas or nitrogen gas in addition to argon gas.

[0093] An RF power supply 66 for applying a high frequency voltage is connected to the cylindrical electrode 61. A matching box 67, which is a matching circuit, is connected in series to the output side of the RF power supply 66. The RF power supply 66 is also connected to the chamber 20. When a voltage is applied from the RF power supply 66, the cylindrical electrode 61 acts as an anode, and the chamber 20, the shield 62, the turntable 31, and the tray 11 act as cathodes. In other words, they function as electrodes for reverse sputtering. For this reason, the turntable 31 and the tray 11 are conductive and are in contact with each other so as to be electrically connected.

[0094] The matching box 67 stabilizes the plasma discharge by matching the impedance on the input side and the output side. The chamber 20 and the turntable 31 are grounded. The shield 62 connected to the chamber 20 is also grounded. The RF power supply 66 and the process gas inlet 65 are both connected to the cylindrical electrode 61 via a through hole provided in the housing 61d.

[0095] Argon gas, which is the process gas G3, is introduced into the cylindrical electrode 61 from the process gas inlet 65, and when a high frequency voltage is applied to the cylindrical electrode 61 from the RF power source 66, a capacitively coupled plasma is generated, and the argon gas is converted into plasma, generating electrons, ions, radicals, etc. The ions in the generated plasma are irradiated onto the film in the process of being formed on the workpiece 10.

[0096] That is, the surface treatment section 60 has a cylindrical electrode 61 with an opening 61a at one end and into which a process gas G3 is introduced, and an RF power source 66 that applies a high frequency voltage to the cylindrical electrode 61, and the conveying section 30 conveys the workpiece 10 directly below the opening 61a and passes it through, thereby attracting ions into the film formed on the workpiece 10 and performing ion irradiation. In the surface treatment section 60, a negative bias voltage is applied to the tray 11 on which the workpiece 10 is placed and the rotating table 31 in order to attract ions into the film formed on the workpiece 10.

[0097] By using a cylindrical electrode 61 such as the surface treatment section 60, it is possible to attract ions into the formed thin film by applying a desired negative bias voltage to the tray 11 and turntable 31 on which the workpiece 10 is placed, while keeping these members at earth potential, without applying a high-frequency voltage to the tray 11 and turntable 31. This makes it unnecessary to add a structure for applying a high-frequency voltage to the tray 11 and turntable 31, or to consider the area ratio of the anode electrode to the area of ​​other members surrounding the cathode electrode in order to obtain a desired bias voltage, making it easier to design the device.

[0098] Therefore, even when film formation and ion irradiation are repeated while the workpiece 10 is moved, ions can be attracted to the film formed on the workpiece 10 with a simple structure, and the film in the process of being formed on the workpiece 10 can be flattened.

[0099] The cylindrical electrode 61 separates the processing space 64 in the chamber 20 where the surface treatment is performed by the surface treatment unit 60. The cylindrical electrode 61 can prevent the process gas G3 from diffusing into the chamber 20. That is, the surface treatment unit 60 has a processing space 64 that is smaller than the chamber 20 and is separated from the processing spaces 41 and 59. Since it is only necessary to adjust the pressure in the processing space 64, which is separated into a space smaller than the chamber 20, the pressure can be easily adjusted and the plasma discharge can be stabilized. The order and number of the film forming unit 40, the film treatment unit 50, and the surface treatment unit 60 are not limited to a specific one. It is only necessary that the desired processing can be performed on the workpiece 10 that is circulated and transported.

[0100] In this way, the film processing unit 50 has a function of generating a compound film by converting nitrogen gas into plasma to generate chemical species containing nitrogen atoms, and causing a chemical reaction with the film formed on the workpiece 10. By utilizing inductively coupled plasma with high plasma density, the film processing unit 50 can generate a compound film by efficiently chemically reacting the chemical species in the plasma with the film formed on the workpiece 10 by the film forming unit 40.

[0101] The surface treatment section 60 has a function of applying a negative bias voltage to the tray 11 on which the workpiece 10 is placed and the rotating table 31, thereby attracting ions into the film formed on the workpiece 10 and flattening the thin film. In the surface treatment section 60, by utilizing the cylindrical electrode 61, it is possible to easily attract ions into the film formed on the workpiece 10 and flatten it.

[0102] [Transfer section] 1, the transfer unit 70 is a device that transfers the workpiece 10 into and out of the chamber 20 via a load lock chamber 71 while maintaining the vacuum inside the chamber 20. The transfer of the workpiece 10 between the transfer unit 70 and the rotary table 31 is performed by a transport mechanism (not shown).

[0103] [Control device] The control device 90 controls various elements constituting the film forming apparatus 1, such as the exhaust unit 23, the sputtering gas introduction unit 49, the process gas introduction units 58, 65, the power supply unit 46, the RF power supplies 54, 66, the motor 32, and the transport unit 70. The control device 90 is a processing device including a PLC (Programmable Logic Controller) and a CPU (Central Processing Unit), and stores a program describing the control contents.

[0104] For example, the control device 90 controls the initial exhaust pressure of the film forming apparatus 1, the power applied to the target 42, the antenna 53, and the cylindrical electrode 61, the flow rates of the sputtering gas G1 and the process gases G2 and G3, the introduction time and exhaust time, the film forming time, the surface treatment time, the heating temperature and heating time of the heating unit 34, the rotation speed of the motor 32, the cooling temperature, the cooling time, etc. This allows the control device 90 to handle a wide variety of film forming specifications.

[0105] Furthermore, the control device 90 controls the heating temperature of the heating unit 34. To this end, the control device 90 has a temperature sensor, a temperature regulator, and an operation unit. The temperature sensor detects the temperature of the heating unit 34 and sends a signal of the detected temperature value to the temperature regulator. The temperature regulator compares the detected temperature value with a preset target temperature value and sends an operation signal to the operation unit. The operation unit applies or stops applying power to the ring electrode 351a via the brush electrode 352a based on the operation signal, thereby raising or lowering the temperature of the heating unit 34. In this way, the control device 90 controls the temperature of the heating unit 34 by performing feedback control. The temperature sensor can be, for example, a thermocouple that is in contact with the heating unit 34 and is provided so as to be able to detect the temperature. The operation unit can be, for example, a voltage regulator such as an SCR (Silicon Controlled Rectifier).

[0106] The heating temperature of the heating unit 34 is controlled so that the temperature of the workpiece 10 rises stepwise to the target temperature. In other words, the heating unit 34 is provided so that the temperature of the workpiece 10 can be adjusted stepwise. "Stepwise" is synonymous with "gradually," "gently," and "not suddenly," and means that the time from the start of heating to the target temperature is long enough to prevent damage to the workpiece 10. The control device 90 can also adjust the heating temperature of the heating unit 34 according to the type of workpiece 10. The heating temperatures of the multiple heating units 34 can be individually adjusted. This allows different types of workpieces 10, such as sapphire substrates and silicon wafers, to be placed on the turntable 31 and processed simultaneously in parallel.

[0107] [Operation] Next, the operation of the film forming apparatus 1 controlled by the control device 90 will be described with reference to Figs. 7 and 8 in addition to Figs. 1 to 6. Fig. 7 is a flowchart of a film forming process by the film forming apparatus 1 of this embodiment. Note that a film forming method for forming a film by the film forming apparatus 1 as described below is also one aspect of the present invention.

[0108] This film formation process is a process in which an AlN film and a GaN film are alternately laminated on a workpiece 10, and a GaN layer is further formed. Silicon wafers and sapphire substrates have different crystal lattices from GaN, so if a GaN film is directly formed on them, there is a problem that the crystallinity of the GaN decreases. In order to eliminate such a mismatch of crystal lattices, a buffer layer is formed by alternately laminating an AlN film and a GaN film, and a GaN layer is formed on this buffer layer. The film formation apparatus 1 can be used, for example, when forming a buffer layer and a GaN layer on a silicon wafer in the manufacture of a horizontal MOSFET or LED.

[0109] For example, Fig. 8(A) shows the layered structure of an LED, in which a buffer layer 10a, a GaN layer 10b including an n-channel, a buffer layer 10a, a GaN layer 10c including a p-channel, a light-emitting layer 10d, and a transparent conductive film 10e are layered on a silicon workpiece 10. The transparent conductive film 10e is an ITO (Indium Tin Oxide) film. Note that electrodes are not shown. Fig. 8(B) shows the detailed structure of the buffer layer 10a.

[0110] First, the inside of the chamber 20 is evacuated from the exhaust port 21 by the exhaust unit 23, and is constantly depressurized to a predetermined pressure. In addition, the heating unit 34 starts heating along with the exhaust. At the same time, the turntable 31 starts rotating. The inside of the chamber 20 is heated by radiation from the rotating heating unit 34 (step S101). Heating along with the exhaust promotes the desorption of residual gases such as water molecules and oxygen molecules in the chamber 20. This makes it difficult for the residual gases to be mixed in as impurities during film formation, improving the crystallinity of the film. After a gas analyzer such as Q-Mass detects that the oxygen concentration in the chamber 20 has fallen below a predetermined value, the rotation of the turntable 31 is stopped.

[0111] Next, the tray 11 carrying the workpieces 10 is carried into the load lock chamber 71 of the transfer section 70 (step S102). The turntable 31 moves the empty holding areas HA sequentially to the loading / unloading entrance 24. Each holding area HA individually holds the tray 11 carried in by the transport mechanism. In this way, the trays 11 carrying the workpieces 10 are placed in all holding areas HA on the turntable 31. This completes the carrying of the workpieces 10 into the chamber 20.

[0112] Furthermore, the cooling device 423 is operated to start cooling the cooling medium and supplying it to the cooling block 420, whereby the cooling medium circulates through the flow path of the cooling block 420 (step S103). The turntable 31 starts rotating again, and the workpieces 10 are heated by the heating unit 34, and the oxide film on the surface of the workpieces 10 is removed by the surface treatment unit 60 (step S104). At this time, the absorbing member 12 is heated by the heating unit 34, and the absorbing member 12 emits electromagnetic waves with a wavelength that is easily absorbed by the workpieces 10, facilitating the heating of the workpieces 10 on each tray 11.

[0113] Furthermore, as the turntable 31 rotates, the workpiece 10 passes under the surface treatment section 60. In the surface treatment section 60, a process gas G3 is introduced into a cylindrical electrode 61 from a process gas inlet 65, and a high-frequency voltage is applied to the cylindrical electrode 61 from an RF power source 66. The application of the high-frequency voltage turns the process gas G3 into plasma, and ions in the plasma collide with the surface of the workpiece 10 passing under the opening 61a, thereby removing the oxide film from the surface of the workpiece 10.

[0114] The workpiece 10 is repeatedly passed under the surface treatment section 60, and the surface treatment section 60 performs treatment for a predetermined time required for removing the oxide film, which is determined in advance by an experiment, and then the film formation section 40B and the film treatment section 50 alternately perform the formation of an AlN film and the film formation section 40A and the film treatment section 50 alternately perform the formation of a GaN film. As described above, the film formation section 40A is provided with a target 42 made of a material containing Ga and GaN, and the film formation section 40B is provided with a target 42 made of a material containing Al. In this film formation process, the film formation material adheres to the inner surface of the adhesion prevention plate 410. The adhesion prevention plate 410 is heated by the heating section 34, but is cooled by the cooling block 420, so that the film formation material deposited on the adhesion prevention plate 410 is less likely to peel off due to thermal expansion.

[0115] First, an AlN film is formed on the workpiece 10 by the film forming unit 40B and the film processing unit 50 (step S105). That is, the sputtering gas inlet 49 supplies a sputtering gas G1 into the processing space 41 of the film forming unit 40B through the gas inlet 47. The sputtering gas G1 is supplied to the periphery of the target 42 made of Al. The power supply unit 46 applies a voltage to the target 42 of the film forming unit 40B. This causes the sputtering gas G1 to become plasma. Ions generated by the plasma collide with the target 42 and knock out sputter particles containing Al atoms. The workpiece 10 passes repeatedly under the film forming unit 40B as the turntable 31 rotates.

[0116] A thin film is formed on the surface of the workpiece 10 by deposition of sputtered particles containing Al atoms when the workpiece 10 passes through the deposition section 40B. In this embodiment, a film thickness that can contain 1 to 2 Al atoms in the thickness direction can be deposited every time the workpiece 10 passes through the deposition section 40B.

[0117] The workpiece 10 that has passed through the film forming section 40B passes through the film processing section 50, during which the Al atoms of the thin film are nitrided. That is, the process gas inlet 58 supplies a process gas G2 containing nitrogen gas through the gas inlet 56. The process gas G2 containing nitrogen gas is supplied to a processing space 59 sandwiched between the window member 52 and the rotating table 31. The RF power source 54 applies a high frequency voltage to the antenna 53.

[0118] An electric field generated by the antenna 53 through which a high-frequency current flows due to application of a high-frequency voltage is generated in the processing space 59 via the window member 52. This electric field excites the process gas G2 containing nitrogen gas supplied to this space, generating plasma. The nitrogen chemical species generated by the plasma collide with the thin Al film on the workpiece 10 and combine with the Al atoms, forming a sufficiently nitrided AlN film.

[0119] The workpiece 10, which has passed through the film treatment section 50 by the rotation of the turntable 31 and has the AlN film formed thereon, heads to the surface treatment section 60, where ions are irradiated onto the AlN film (step S106). That is, the process gas introduction section 65 supplies a process gas G3 containing argon gas through a pipe. This process gas G3 is supplied to the space inside the cylindrical electrode 61 surrounded by the cylindrical electrode 61 and the turntable 31. When a voltage is applied to the cylindrical electrode 61 by the RF power supply 66, the cylindrical electrode 61 acts as an anode, and the chamber 20, the shield 62, the turntable 31, and the tray 11 act as cathodes, exciting the process gas G3 supplied to the space inside the cylindrical electrode 61 to generate plasma. Furthermore, the argon ions generated by the plasma collide with the AlN film formed on the workpiece 10, thereby moving particles to sparse portions of the film and flattening the film surface.

[0120] Thus, in steps S105 and S106, the workpiece 10 passes through the processing space 41 of the film formation unit 40B in operation to perform the film formation process, and the workpiece 10 passes through the processing space 59 of the film treatment unit 50 in operation to perform the nitriding process. Then, the AlN film formed on the workpiece 10 is planarized by the workpiece 10 passing through the space in the cylindrical electrode 61 of the surface treatment unit 60 in operation. Note that "operating" is synonymous with a plasma generating operation that generates plasma in the processing space of each unit 40, 50, 60.

[0121] The turntable 31 continues to rotate until an AlN film of a predetermined thickness is formed on the workpiece 10, that is, until a predetermined time obtained in advance by simulation, experiment, or the like has elapsed (step S107 No). In other words, the workpiece 10 continues to circulate between the film formation unit 40 and the film processing unit 50 until an AlN film of a predetermined thickness is formed. Since it is preferable to perform nitriding each time Al is deposited to an atomic level film thickness, it is preferable to determine the film formation speed, the nitriding speed, and the rotation speed of the turntable 31 (the speed of passing through each processing unit) so that the film formation and nitriding are balanced. For example, the rotation speed of the turntable 31 is set to about 50 to 60 rpm.

[0122] When a predetermined time has elapsed (Yes in step S107), the operation of the film forming unit 40B is stopped. Specifically, the application of voltage to the target 42 by the power supply unit 46 is stopped.

[0123] Next, a GaN film is formed on the workpiece 10 by the film forming unit 40A and the film processing unit 50 (step S108). Then, the GaN film is planarized (step S109). That is, the sputtering gas G1 supplied to the processing space 41 of the film forming unit 40A is turned into plasma by supplying the sputtering gas G1 to the periphery of the target 42 of the film forming unit 40A by the sputtering gas introduction unit 49 and applying a voltage to the target 42 of the film forming unit 40A by the power supply unit 46. Ions generated by the plasma collide with the target 42 and knock out sputtered particles containing Ga atoms. The workpiece 10 passes repeatedly under the film forming unit 40A by the rotation of the turntable 31.

[0124] The workpiece 10 that has passed through the film forming section 40A passes through the film processing section 50, during which Ga atoms in the thin film are nitrided. That is, a process gas introduction section 58 supplies a process gas G2 containing nitrogen gas through a gas introduction port 56. The process gas G2 containing nitrogen gas is supplied to a processing space 59 sandwiched between a window member 52 and a rotating table 31. An RF power source 54 applies a high frequency voltage to an antenna 53.

[0125] An electric field generated by the antenna 53 through which a high-frequency current flows due to application of a high-frequency voltage is generated in the processing space 59 through the window member 52. This electric field excites the process gas G2 containing nitrogen gas supplied to this space, generating plasma. The nitrogen chemical species generated by the plasma collide with the GaN thin film on the workpiece 10 and combine with Ga atoms, forming a sufficiently nitrided GaN film.

[0126] The workpiece 10, which has passed through the film treatment section 50 and has the GaN film formed thereon, heads to the surface treatment section 60, where the GaN film is irradiated with ions (step S108). By colliding with the GaN film formed on the workpiece 10, the particles are moved to sparse portions of the film, flattening the film surface.

[0127] As a result, a thin film in which sputtered particles containing Ga atoms are deposited on the surface of the AlN film. In this embodiment, a film can be deposited to a thickness that can contain 1 to 2 Ga atoms each time the film passes through the film deposition unit 40.

[0128] Thus, in steps S108 to S109, the workpiece 10 passes through the processing space 41 of the operating film forming unit 40A to form a film containing Ga, and the workpiece 10 passes through the processing space 59 of the operating film processing unit 50 to perform a nitriding process to form a GaN film. Then, the workpiece 10 passes through the space in the cylindrical electrode 61 of the operating surface processing unit 60 to planarize the GaN film formed on the workpiece 10 (step S109).

[0129] When the time required for a GaN film of a predetermined thickness to be formed on the workpiece 10 has elapsed, which is obtained by simulation or experiment, the turntable 31 first stops the operation of the film forming unit 40. That is, when the predetermined time has elapsed (Yes in step S110), the operation of the film forming unit 40A is stopped. Specifically, the application of voltage to the target 42 by the power supply unit 46 is stopped. Since it is preferable to perform nitridation every time Ga is deposited to an atomic level thickness, it is preferable to determine the film formation speed, nitridation speed, and rotation speed of the turntable 31 (the speed of passing through each processing unit) so that the film formation and nitridation are balanced. For example, the rotation speed of the turntable 31 is set to about 50 to 60 rpm.

[0130] The formation of the AlN film and the GaN film is repeated until a predetermined number of layers is reached (Step S111 No.) When the predetermined number of layers is reached (Step S111 Yes), the formation of the buffer layer is terminated.

[0131] Subsequently, a GaN layer is further formed on the buffer layer (step S112). The formation of this GaN layer is performed in the same manner as the formation of the GaN film in the buffer layer described above. However, the film is formed for a time period that will result in a predetermined thickness set for the GaN layer.

[0132] After the buffer layer and the GaN layer are formed as described above, the operation of the film forming unit 40A is stopped as described above, and then the operation of the film processing unit 50 is stopped (step S113). Specifically, the supply of high frequency power to the antenna 53 by the RF power supply 54 is stopped. Then, the rotation of the turntable 31 is stopped, and the tray 11 on which the film-formed workpiece 10 is placed is removed from the chamber 20 and the load lock chamber 71 (step S114). Then, the cooling device 423 is stopped (step S115).

[0133] The cooling device 423 may be in a constant operating state, or may be stopped at the discretion of the operator. For example, if the film forming apparatus 1 is operated 24 hours a day, the cooling device 423 will be in constant operation and will be stopped during maintenance or the like. Furthermore, the cooling device 423 is at least stopped after the entire process is completed, rather than every time the workpiece 10 is discharged from the film forming apparatus 1. For example, the cooling device 423 is stopped after the processing of a preset number of sheets is completed.

[0134] In the above description, the film processing unit 50 and the surface processing unit 60 are operated continuously during the formation of the buffer layer (steps S105 to S112), but the operation of the film processing unit 50 and the surface processing unit 60 may be stopped after each step of steps S105 to S112 is completed. In this case, the operation of the film processing unit 50 is stopped after the operation of the film forming units 40B and 40A is stopped. In this manner, the operation may be stopped for each step. It is sufficient if the AIN film and the GaN film can be formed, regardless of whether the nitridation is sufficient or not.

[0135] [effect] (1) The film forming apparatus 1 of this embodiment includes a chamber 20 capable of evacuating the inside thereof, a table provided within the chamber 20 for holding a number of workpieces 10, a plasma generator P1 for converting a gas introduced into the chamber 20 into plasma, a film forming unit 40 for forming a film on the workpiece 10 supported on the table, an adhesion prevention plate 410 arranged to surround a processing space 41 in which a film is formed on the workpiece 10 by the film forming unit 40 and preventing the adhesion of the film forming material to the inside of the chamber 20, a cooling block 420 provided within the chamber 20 and having a contact surface 421 that directly contacts the adhesion prevention plate 410 and that cools the adhesion prevention plate 410 by contacting the contact surface 421, and a flow path 422 provided in the cooling block 420 through which a cooling medium flows.

[0136] The table is a rotating table 31 that holds a plurality of workpieces 10 and circulates the workpieces 10 in a circular trajectory. The film forming section 40 converts a sputtering gas G1 introduced between a target 42 made of a film forming material and the rotating table 31 into plasma by a plasma generator P1, and deposits particles of the film forming material by sputtering onto the workpieces 10 being circulated by the rotating table 31 to form a film.

[0137] In this way, the contact surface 421 of the cooling block 420 is brought into direct contact with the adhesion prevention plate 410, thereby cooling the adhesion prevention plate 410. The thermal expansion of the adhesion prevention plate 410 is suppressed, and the peeling of the film-forming material attached to the adhesion prevention plate 410 can be suppressed. In addition, the film-forming material attached to the adhesion prevention plate 410 can be prevented from peeling off and falling onto the workpiece 10, so that the occurrence of quality defects in the film-forming process can be suppressed. Furthermore, since the cooling block 420 does not have a configuration in which the cooling pipe is in direct contact with the adhesion prevention plate 410, it is possible to suppress the cooling medium from leaking into the chamber 20 due to damage to the cooling pipe or the like. Since the part of the cooling block 420 that is in direct contact with the adhesion prevention plate 410 is a block, that is, the part that is arranged in the chamber 20 is a block, the cooling block 420 is less likely to be damaged than the cooling pipe. Since the cooling block 420 is configured to cool the adhesion prevention plate 410 by contact with the contact surface 421, the cooling block 420 has a larger area in contact with the adhesion prevention plate 410 than the cooling pipe, and therefore has excellent cooling efficiency.

[0138] When cooling the same area as the cooling block 420 with water-cooling pipes, it is necessary to increase the number of cooling pipes, which complicates the structure and makes maintenance difficult. For example, when removing the adhesion prevention plate 410, it is time-consuming to remove and install the cooling pipes while preventing leakage of the cooling medium. On the other hand, in this embodiment, the water-cooling pipes do not get in the way when removing and installing the adhesion prevention plate 410, making maintenance easy. Furthermore, the cooling block 420 itself has a simpler configuration than the cooling pipes, so it is easy to remove and has excellent maintainability.

[0139] Furthermore, when a film is formed while the workpiece 10 is circulated and transported by the turntable 31, if the film forming material peels off from the adhesion prevention plate 410, the film forming material leaks from the processing space 41 through the gap between the adhesion prevention plate 410 and the turntable 31, and the inside of the chamber 20 is likely to be contaminated. However, in this embodiment, the peeling of the film forming material from the adhesion prevention plate 410 can be suppressed, so that the contamination inside the chamber 20 can be prevented.

[0140] (2) A heating unit 34 for heating the workpiece 10 is provided inside the chamber 20. Therefore, the temperature inside the chamber 20 is likely to increase due to the heating unit 34, but the cooling block 420 suppresses the thermal expansion of the adhesion prevention plate 410, thereby reducing peeling of the film-forming material.

[0141] (3) In the turntable 31, the heating units 34 are disposed in a plurality of holding areas HA where the individual workpieces 10 are held. For this reason, the holding areas HA heated by the heating units 34 repeatedly pass through the positions facing the adhesion-prevention plate 410, which makes it easier for the temperature of the adhesion-prevention plate 410 to rise. However, the thermal expansion is suppressed by the cooling block 420, which reduces peeling of the film-forming material.

[0142] (4) The cooling block 420 is provided along the gap between the outer periphery of the turntable 31 and the inner wall of the side surface 20c of the chamber 20. Therefore, the cooling block 420 can be arranged by effectively utilizing the gap between the turntable 31 and the inner wall of the side surface 20c of the chamber 20, which is for ensuring the rotation of the turntable 31, and the size of the chamber 20 can be prevented from increasing.

[0143] (5) The contact surface 421 contacts the bottom of the attachment plate 410 and supports the attachment plate 410. Therefore, the cooling block 420 does not get in the way during maintenance, and the attachment plate 410 supported by the contact surface 421 can be easily removed.

[0144] (6) A heat transfer section 413 having an area expanded in a direction parallel to the rotation plane (table plane) of the turntable 31 is provided at the bottom of the adhesion prevention plate 410, and the contact surface 421 is in contact with the heat transfer section 413. Therefore, heat from the adhesion prevention plate 410 can be transferred to the cooling block 420 over a wider area, enabling efficient cooling.

[0145] (7) The flow path 422 of the cooling block 420 is airtightly connected to the cooling device 423 arranged outside the chamber 20 and cooling the cooling medium so as to maintain the vacuum inside the chamber 20. Therefore, the cooling medium is prevented from being heated by the heat inside the chamber 20, and efficient cooling is possible. That is, the pipe 422d is directly connected to the outside of the chamber 20 from the cooling block 420 through the wall of the chamber 20 without passing through the inside of the chamber 20. Therefore, the pipe 422d is not heated in the path passing through the chamber 20, and can directly receive the heat of the adhesion prevention plate 410 and discharge it to the outside, so that efficient cooling can be achieved. This can reduce peeling of the film forming material due to thermal expansion of the adhesion prevention plate 410, and further, can suppress the film forming material from falling from the adhesion prevention plate 410 onto the workpiece 10. In this embodiment, the joint 422c and the cooling block 420 are integrally formed, and the joint between the joint 422c and the pipe 422d is on the atmospheric side. In this manner, the absence of seams within the chamber 20 prevents leakage of the cooling medium into the chamber 20 in a vacuum.

[0146] (8) A plurality of cooling blocks 420 are provided, and the flow paths of the plurality of cooling blocks 420 are connected to each other via piping provided outside the chamber 20 so that the cooling medium can flow. Therefore, by arranging a plurality of cooling blocks 420, the area of ​​the contact surface 421 is ensured, while the degree of freedom of layout according to the arrangement of the members in the chamber 20 is increased. In addition, since the piping connecting the plurality of cooling blocks 420 does not pass through the chamber 20, the cooling efficiency is good as described above. This can reduce peeling of the film forming material due to thermal expansion of the adhesion prevention plate 410, and can prevent the film forming material from falling onto the workpiece 10 from the adhesion prevention plate 410.

[0147] (9) The film forming apparatus 1 has a surface treatment section 60 that treats the surface of at least one of the workpiece 10 and the film being circulated and transported by the rotary table 31. The film forming section 40 includes a GaN film forming section 40A that deposits particles of a film forming material containing GaN, and the film processing section 50 includes a nitriding processing section that nitrides the particles of the film forming material deposited in the GaN film forming section 40A. This makes it possible to reduce peeling of the film forming material due to thermal expansion of the adhesion prevention plate 410 when performing surface treatment of the workpiece 10 in which heating is effective, or when forming a film using a film forming material in which heating is effective. Furthermore, it is possible to prevent the film forming material from falling from the adhesion prevention plate 410 onto the workpiece 10.

[0148] [Variations] The present invention is not limited to the above-described embodiment. The following modified examples are also applicable, provided that the basic configuration is similar to that of the above-described embodiment.

[0149] (1) In the above embodiment, the film forming apparatus 1 forms a film while circulating and transporting the work 10 on a circular track by the rotating table 31, but the present invention is not limited to such a circulating transport type film forming apparatus 1. For example, as shown in Figs. 9 and 10, the film forming apparatus 1 has a table ST for supporting the work 10 in a chamber 20, a plasma generator P1 for converting a gas introduced into the chamber 20 into plasma, and a film forming unit 40 for forming a film on the work 10 supported by the table ST. An adhesion prevention plate 410 and a cooling block 420 may be provided in the chamber 20 of the film forming apparatus 1. In this case, a heating unit 34 is built into the table ST.

[0150] The chamber 20 is box-shaped, and a rectangular parallelepiped processing space 41 is formed therein. The adhesion prevention plates 410 are four rectangular flat plates arranged along the inside of the four side surfaces 20c of the processing space 41 so as to cover the inner walls. The cooling block 420 is rectangular and arranged between the inner wall of the side surface 20c of the chamber 20 and the adhesion prevention plates 410, and has a contact surface 421 that directly contacts the adhesion prevention plates 410. As shown in FIG. 11, a meandering flow path 422 is provided inside the cooling block 420. In this film forming apparatus 1, peeling of the film forming material due to thermal expansion of the adhesion prevention plates 410 can also be suppressed.

[0151] (2) In the above embodiment, the contact surface 421 of the cooling block 420 is the upper surface, but as shown in Fig. 9, it may be a side surface. That is, in the above embodiment, the upper surface of the cooling block 420 is in contact with the lower end side of the adhesion prevention plate 410, but this is not limited thereto. For example, the cooling block 420 may be in contact with the body part 411 of the adhesion prevention plate 410. In this case, it is preferable that the contact surface 421 of the cooling block 420 is shaped to fit the outer periphery of the body part 411 of the adhesion prevention plate 410.

[0152] Also, the contact surface 421 of the cooling block 420 may be in contact with the upper end of the adhesion prevention plate 410. In this case, the cooling block 420 is disposed between the top surface 20a of the chamber 20 and the adhesion prevention plate 410, but the cooling block 420 may be disposed so as not to contact the inner wall of the top surface 20a, or the cooling block 420 may be made of an elastic body with good thermal conductivity so that contact with the top surface 20a is not a problem. In this way, if there is a space between the top surface 20a and the adhesion prevention plate 410 in which the cooling block 420 can be placed, the cooling block 420 may be installed in that space, and in this case, the thickness of the cooling block 420 may be thinner than that of the above embodiment. In other words, it is sufficient that the thickness is such that the flow path 422 of the cooling medium can be formed.

[0153] Furthermore, the cooling block 420 may be configured in a combination of a configuration in which it contacts the lower end of the adhesion prevention plate 410, a configuration in which it contacts the side of the adhesion prevention plate 410, and a configuration in which it contacts the upper end of the adhesion prevention plate 410.

[0154] (3) In the above embodiment, the cooling block 420 is in contact with the inner wall (side surface 20c, bottom surface 20b) of the chamber 20. However, a gap may be provided between the cooling block 420 and the inner wall of the chamber 20 to provide a reduced pressure space. Also, a heat insulating material may be interposed between the cooling block 420 and the inner wall of the chamber 20. This can prevent heat from entering from the chamber 20 and increase the cooling efficiency of the adhesion prevention plate 410.

[0155] (4) The cooling block 420 can be easily maintained by dividing it into a plurality of parts as described above, but it may be an integrated type. For example, the two cooling blocks 420 in the above embodiment may be integrated. Furthermore, there may be only one cooling block 420 corresponding to the plurality of adhesion prevention plates 410. In other words, the plurality of adhesion prevention plates 410 may be in contact with a common cooling block 420.

[0156] (5) In the above embodiment, the heating unit 34 is provided on the turntable 31 and the table ST, but this is not limited to the above. In addition, the cooling block 420 of the present invention can be applied to a film forming apparatus 1 that does not have a heating unit 34 because the problem of thermal expansion due to heating of the adhesion prevention plate 410 occurs. In addition, the film forming unit 40 is not limited to an embodiment in which a film is formed by sputtering. For example, the film forming unit 40 can be a plasma CVD film forming unit.

[0157] (6) The configuration of the transfer unit 70 is not limited to the above-mentioned embodiment as long as the transfer unit 70 is configured to transfer the workpiece 10 while maintaining the pressure inside the chamber 20. For example, the transfer unit 70 may be configured to transfer the workpiece 10 via a load lock chamber provided on the top surface 20a of the chamber 20.

[0158] (7) In the above embodiment, the surface treatment unit 60 is provided inside the chamber 20, but a surface treatment unit may be provided outside the chamber 20. This surface treatment unit is provided with a cylindrical electrode, an RF power source, and a process gas inlet, similar to the surface treatment unit 60, and can perform oxide film removal treatment on the carried-in workpiece 10 in a stationary state.

[0159] (8) The shape and number of the heat shield plates 36a are not limited to the above embodiment. The heat shield portion 36 is disposed so as to cover the lower surface of the turntable 31 at a distance, but the heat shield plates 36a may be stacked to cover the lower surface of the turntable 31 at a position corresponding to the holding area HA. ​​Also, the heat shield plates 36a are shaped like a U-shape and are formed by laminating them together. Also, although the heat shield plates 36a are formed of a side plate and a flat plate, the heat shield effect can be obtained even if they are formed of only a flat plate.

[0160] (9) In the above embodiment, a plurality of heating parts 34 are arranged, and each ring electrode 351a is connected to the heating part 34 by a cable 351b. The number of heating parts 34 connected to one ring electrode 351a may be one or more. When a plurality of heating parts 34 are connected to one ring electrode 351a, for example, selected heating parts 34 among the plurality of heating parts 34 are electrically connected to each other, and the ring electrode 351a is connected to only the representative heating part 34 via the cable 351b. This makes it possible to reduce the number of ring electrodes 351a compared to the number of heating parts 34, and to shorten the length of the rotating electrode part 351. As a result, the rotating shaft 311 on which the rotating electrode part 351 is arranged can be shortened, and the device installation space can be reduced and the rotation stability of the rotating table 31 can be improved.

[0161] (10) The types and numbers of film formation units 40, film processing units 50, and surface processing units 60 provided in chamber 20 are not limited to the above. There may be one film formation unit 40, or three or more. There may be a plurality of film processing units 50 and surface processing units 60. For example, the film formation unit 40 may be configured as a film formation apparatus 1 for forming a GaN film with only film formation unit 40A. In addition to the above-mentioned film formation unit 40, a film formation unit 40 using a different type of target material, a film formation unit 40 using the same type of target material, or a film processing unit 50 may be added.

[0162] Also, for example, a film-forming unit having a target 42 containing indium oxide and tin oxide, which are the ITO film-forming materials, may be added so that an ITO film can be formed in the chamber 20. In this case, instead of introducing nitrogen gas, oxygen gas may be introduced into the film processing unit 50 to compensate for the oxidation of the ITO film. Also, for example, the film-forming units 40A and 40B and the film processing unit 50 may be operated simultaneously so that an AlGaN (Aluminum Gallium Nitride) film containing Ga, Al, and N can be formed. This AlGaN film functions as the light-emitting layer of the LED. In other words, the light-emitting layer can also be formed in the chamber 20.

[0163] (11) The film forming section 40 is made of gallium oxide (Ga 2 O 3 The film processing section 50 may include a film formation section that deposits particles of a film formation material containing Ga atoms and oxygen (O), and the film processing section 50 may include an oxidation processing section that oxidizes the particles of the film formation material deposited in the film formation section. That is, instead of or in addition to the above-mentioned film formation section 40A, a film formation section that uses a material containing Ga atoms and oxygen (O) as the target 42 may be provided, and instead of or in addition to the nitriding processing section, an oxidation processing section that uses a gas containing oxygen as the process gas G2 may be provided.

[0164] (12) In addition to the above embodiment, the film forming unit 40 may have a film forming unit having a target 42 made of a film forming material containing InN. Simple indium (In) has a low melting point, so an InN target is actually used to which nitrogen (N) is added in order to obtain a solid target 42. As described above, the InN target contains In atoms that are insufficiently bonded to nitrogen.

[0165] (13) In addition to the above embodiment, an impurity doping section may be provided to dope the formed GaN film with n-type or p-type impurities (dopants). In this case, the film forming section, the nitriding section, and the impurity doping section are arranged in this order on the circulation transport path. The impurity doping section has the same configuration as the film forming section 40.

[0166] In this embodiment, when forming the GaN film, a layer including a p-channel (p-type semiconductor) in which Mg ions are added to the GaN layer can be formed together with the film forming unit 40A and the film processing unit 50. Also, when forming the GaN film, a layer including an n-channel (n-type semiconductor) in which Si ions are added to the GaN layer can be formed together with the film forming unit 40A and the film processing unit 50.

[0167] The n-type impurities or p-type impurities added in the impurity adding processing section are not limited to those exemplified above. For example, the n-type impurities may be Ge or Sn. In this case, the film forming material constituting the target provided in the impurity adding processing section may be a film forming material containing Ge or Sn instead of Si.

[0168] [Other embodiments] Although the embodiment of the present invention and the modified examples of each part have been described, these embodiments and the modified examples of each part are presented as examples and are not intended to limit the scope of the invention. These novel embodiments described above can be implemented in various other forms, and various omissions, substitutions, modifications, and combinations can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are included in the invention described in the claims. [Explanation of symbols]

[0169] 1 Film deposition equipment 10 Work 10a Buffer layer 10b GaN layer 10c GaN layer 10d Light-emitting layer 10e transparent conductive film 11 Tray 11a hole 11b Positioning hole 12 Absorbing material 20 Chamber 20a Top 20b Bottom 20c side 20d through hole 20e Fastening members 21 Exhaust port 21a opening 22 Through hole 23 Exhaust section 24 Loading / unloading entrance 30 Conveyor 31 Rotating Table 31a Insertion hole 31b Fastening member 31c retaining hole 32 Motor 33 Insulation section 34 Heating section 35 Rotating joint 36 Heat shield 36a Heat shield 36b Support leg 40 Film forming section 40A Film forming section 40B Film forming section 41 Processing Space 42 Target 43 Backing Plate 44 electrode 46 Power supply section 47 Gas inlet 48 Piping 49 Sputtering gas inlet 50 Membrane processing section 51 Cylindrical body 52 Window Materials 53 Antenna 54 Power supply 54 RF power supply 55 Matching Box 56 Gas inlet 57 Piping 58 Process gas inlet 59 Processing Space 60 Surface Treatment Section 61 Cylindrical electrode 61a opening 61b flange 61c Insulating materials 61d Housing 62 Shield 64 Processing Space 65 Process gas inlet 66 RF power supply 67 Matching Box 70 Transfer section 71 Load Lock Chamber 90 Control device 311 Rotational axis 311a center hole 311b Plate 351 Rotating electrode part 351a Ring electrode 351b Cable 352 Stationary electrode section 352a Brush electrode 352b Cable 410 Anti-adhesion plate 411 Torso 411a aperture 412 Extension 413 Heat transfer section 414 Shielding part 415 Ring 415a Fixed plate 416 Pillar section 420 Cooling Block 421 Contact surface 422 Channel 422a Inlet 422b Outlet 422c fitting 422d Piping 423 Cooling device FA deposition area G1 Sputtering Gas G2 Process Gas G3 Process Gas HA retention area L Transport route P1~P3 Plasma generator T Table

Claims

1. a chamber capable of creating a vacuum therein; A table provided in the chamber and supporting a workpiece; a film forming unit having a plasma generator that converts a gas introduced into the chamber into plasma and forms a film on the work supported on the table; an adhesion prevention plate that is disposed so as to surround a processing space in which a film is formed on the workpiece by the film forming unit and prevents a film forming material from adhering to the inside of the chamber; a cooling block provided in the chamber, the cooling block having a contact surface that directly contacts the deposition prevention plate and that cools the deposition prevention plate by contacting the contact surface; a flow path provided in the cooling block through which a cooling medium flows; A film forming apparatus comprising:

2. the table is a rotary table that holds a plurality of the workpieces and circulates the workpieces along a circular trajectory; 2. The film forming apparatus according to claim 1, wherein the film forming section converts a sputtering gas introduced between a target made of the film forming material and the rotating table into plasma by the plasma generator, and deposits particles of the film forming material by sputtering on the workpiece being circulated and transported by the rotating table to form a film.

3. 3. The film forming apparatus according to claim 1, wherein a heating unit for heating the workpiece is provided in the chamber.

4. 3. The film forming apparatus according to claim 2, wherein heating units are disposed in a plurality of holding areas on the turntable where the workpieces are held individually.

5. 2. The film forming apparatus according to claim 1, wherein the cooling block is provided along a space between an outer periphery of the table and an inner wall of a side surface of the chamber.

6. 3. The film forming apparatus according to claim 1, wherein the contact surface is in contact with a bottom portion of the adhesion prevention plate and supports the adhesion prevention plate.

7. A heat transfer section having an area expanded in a direction parallel to the plane of the table is provided on the bottom of the adhesion prevention plate, 2. The film forming apparatus according to claim 1, wherein the contact surface is in contact with the heat transfer portion.

8. 2. The film forming apparatus according to claim 1, wherein the flow path of the cooling block is airtightly connected to a cooling device arranged outside the chamber for cooling the cooling medium so as to maintain a vacuum within the chamber.

9. 2. The film forming apparatus according to claim 1, wherein the cooling blocks are provided in plurality, and the flow paths of the cooling blocks are connected to each other via piping provided outside the chamber so that the cooling medium can flow therethrough.

10. 3. The film forming apparatus according to claim 2, further comprising a surface treatment section for treating the surface of at least one of the workpiece being circulated and transported by the rotary table and the film formed on the workpiece.

11. a film processing unit that processes a film deposited by the film forming unit on the workpiece being circulated and transported by the rotary table; the film formation unit includes a GaN film formation unit that deposits particles of the film formation material including GaN, 3. The film forming apparatus according to claim 2, wherein the film processing section includes a nitriding section that nitrides particles of the film forming material deposited in the GaN film forming section.

Images