JP2019148002A - Film deposition apparatus - Google Patents

Abstract

To provide a film deposition apparatus capable of growing a semiconductor layer excellent in crystallinity by suppressing collision of gallium particles toward a substrate with other particles.SOLUTION: A first chamber 100 has a target housing part 110 for housing a target T1. A second chamber 200 has a substrate support part 210 for supporting a substrate S1. A partition part 300 has a cylindrical shape part 330, and an opening member 340 covering a first opening end 331 of the cylindrical shape part 330, and having a plurality of open holes for allowing communication between the first chamber 100 and the second chamber 200. The target housing part 110 is arranged so as to face the substrate support part 210. The opening member 340 is arranged between the target housing part 110 and the substrate support part 210.SELECTED DRAWING: Figure 1

Description

  The technical field of this specification relates to a film forming apparatus for forming a thin film using plasma.

  There are various techniques for forming a thin film on a substrate. For example, a sputtering method, a vapor deposition method, a CVD method, and an ion plating method can be used. In the sputtering method, high-speed ions collide with the target in a vacuum, and particles emitted from the target are deposited on the substrate. Since the kinetic energy of ions colliding with the target is large, the kinetic energy of particles emitted from the target is also large. Accordingly, a thin film having a high adhesion can be obtained.

  By the way, conventionally, when a GaN film is formed, an MOCVD method or an HVPE method has been used. In recent years, it has been required to form a GaN film on a large-diameter substrate in view of high productivity. However, the larger the substrate, the greater the strain due to the difference in thermal expansion coefficient between the substrate and the GaN layer. A large stress is generated near the interface between the substrate and the GaN layer. Such stress may adversely affect the crystallinity of the GaN layer. In addition, the stress may cause a piezo electric field inside the semiconductor layer. Therefore, the behavior of electrons in a semiconductor element having such a semiconductor layer may be adversely affected.

  In the sputtering method, there is a possibility that the film can be formed at a lower temperature than the conventional MOCVD method or the like. As the film forming temperature is lower, the stress caused by the difference in thermal expansion coefficient can be suppressed. For this reason, in recent years, a technique using a sputtering method for film formation of GaN has been developed. For example, Patent Document 1 discloses a technique for cooling Ga that is a target (see paragraph [0007] and the like of Patent Document).

JP-A-11-172424

  When forming a GaN film using the sputtering apparatus of Patent Document 1, there is a possibility that Ga target particles directed from the Ga target to the substrate collide with nitrogen gas and argon gas. Ga target particles that have jumped out of the Ga target lose kinetic energy while repeatedly colliding with nitrogen gas and argon gas. Ga target particles that have lost their kinetic energy hardly move around on the surface of the substrate. If the motion state of the Ga target particles is poor, GaN tends to grow three-dimensionally. Then, it becomes difficult to grow a semiconductor layer that is uniform in the surface and excellent in crystallinity.

  The technique of this specification has been made to solve the problems of the conventional techniques described above. The problem is to provide a film forming apparatus capable of suppressing the collision of gallium particles toward the substrate with other particles and growing a semiconductor layer having excellent crystallinity.

  The film-forming apparatus in a 1st aspect has a 1st chamber, a 2nd chamber, and the division part which divides a 1st chamber and a 2nd chamber. The first chamber has a target accommodating portion that accommodates the target. The second chamber has a substrate support portion that supports the substrate. The partition part has an opening member having a first opening end facing the substrate, a plurality of through holes that cover the first opening end of the cylindrical part and communicate the first chamber and the second chamber. And having. The target accommodating portion is disposed at a position facing the substrate support portion. The opening member is disposed at a position between the target accommodating portion and the substrate support portion.

  In this film forming apparatus, the distance between the substrate and the opening member is small. Therefore, the number of times the target particles that have jumped out of the target collide with the gas in the second chamber is small. Therefore, the target particles collide with the substrate while maintaining high kinetic energy. Since the target particles preferably move around on the surface of the substrate or the upper semiconductor layer, a semiconductor layer having excellent crystallinity can be grown. Moreover, it can suppress that target particle | grains and the gas of a 2nd chamber react in the space away from the board | substrate.

  In this specification, there is provided a film formation apparatus capable of suppressing the collision of gallium particles directed toward a substrate with other particles and growing a semiconductor layer having excellent crystallinity.

It is a figure which shows schematic structure of the film-forming apparatus of 1st Embodiment. It is a top view which shows the through-hole of the opening member in the film-forming apparatus of 1st Embodiment. It is a graph which shows the relationship between the distance between the opening member and board | substrate in experiment, and the film-forming speed | rate of GaN. It is a graph which shows the relationship between the distance between the opening member and board | substrate in experiment, and the crystallinity of GaN. It is a scanning microscope picture which shows the relationship between the distance between the opening member and board | substrate in experiment, and the surface morphology of GaN.

  Hereinafter, specific embodiments will be described with reference to the drawings, taking a film forming apparatus and a method for forming a GaN layer as examples.

(First embodiment)
A first embodiment will be described. The film forming apparatus of the first embodiment includes a sputtering apparatus.

1. Film Forming Apparatus FIG. 1 is a diagram showing a schematic configuration of a film forming apparatus 1000 according to the first embodiment. The film forming apparatus 1000 according to the first embodiment is an apparatus that forms a thin film on a substrate by a sputtering method. The film forming apparatus 1000 includes a housing 1001 and a partition unit 300. Here, the material of the housing 1001 and the partition 300 is, for example, Ni-plated SUS. The casing 1001 and the partition unit 300 are grounded.

  The housing 1001 accommodates the first chamber 100 and the second chamber 200. The partition unit 300 accommodates the first chamber 100. The partition unit 300 separates the first chamber 100 and the second chamber 200. That is, the film forming apparatus 1000 includes the first chamber 100, the second chamber 200, and the partition unit 300 that partitions the first chamber 100 and the second chamber 200.

1-1. First Chamber The first chamber 100 includes a target storage unit 110, a target storage unit support unit 120, a cooling unit 130, a first potential application unit 140, a first gas supply unit 150, and a first gas. And a supply pipe 160.

  The target accommodating part 110 is for accommodating the target T1. Therefore, the target accommodating part 110 is good to have a recessed part for mounting the target T1. The target T1 is a material used for sputtering. The target T1 is, for example, Ga. The target accommodating portion 110 is disposed at a position facing a substrate support portion 210 described later.

  The target accommodating portion support 120 is for supporting the target accommodating portion 110. Moreover, the target accommodating part support part 120 has a magnet.

  The cooling unit 130 is for cooling the target accommodating unit 110. The cooling unit 130 includes a flow channel 131 for flowing water, a pump (not shown) for flowing water through the flow channel 131, and a pump control unit (not shown) for controlling the pump. The temperature of water is, for example, 10 ° C. The water temperature may be changed according to the material of the target T1. The cooling unit 130 cools the target T <b> 1 through the target storage unit 110.

  The first potential applying unit 140 is for applying a high-frequency potential to the target accommodating unit 110. Therefore, the first potential applying unit 140 can apply a potential to the target T1 via the target accommodating unit 110. The frequency of the high-frequency potential is, for example, 13.56 MHz. Of course, other frequencies may be used.

  The first gas supply unit 150 is for supplying the first gas into the first chamber 100. The first gas supply unit 150 also plays a role of accommodating the first gas. The first gas supply unit 150 supplies, for example, argon gas as the first gas to the first chamber 100. The first gas is turned into plasma in a first plasma generation region, which will be described later, and becomes particles that enter the target T1 at high speed. The first gas may be other rare gas. The first gas may be other inert gas. However, the first gas is a gas that hardly reacts with the target T1. This is to prevent a reaction product film of the target T1 and the first gas component from forming on the surface of the target T1.

  The first gas supply pipe 160 is a flow path for supplying the first gas from the first gas supply unit 150 to the first chamber 100.

1-2. Second Chamber The second chamber 200 includes a substrate support unit 210, a heating unit 220, a plasma generator 230, a second potential applying unit 240, a second gas supply unit 250, and a second gas supply pipe. 260 and an exhaust port 270.

  The substrate support unit 210 is for supporting the substrate S1. Here, the substrate S1 is a film formation target member on which a thin film is formed by sputtering. The substrate support part 210 is disposed so that the surface of the substrate S1 faces vertically downward.

  The heating unit 220 is for heating the substrate support unit 210. The heating unit 220 can heat the substrate S <b> 1 supported by the substrate support unit 210 via the substrate support unit 210. The heating unit 220 may have a temperature sensor. And it is good for the heating part 220 to hold | maintain board | substrate temperature to the input preset temperature.

  The plasma generator 230 is for converting the second gas supplied from the second gas supply unit 250 into plasma. The plasma generator 230 is, for example, an ICP unit. The plasma generator 230 may generate plasma by other methods.

  The second potential applying unit 240 is for applying a high-frequency potential to the plasma generator 230. The frequency of the high-frequency potential is, for example, 27.12 MHz. Of course, other frequencies may be used.

  The second gas supply unit 250 is for supplying the second gas into the second chamber 200. The second gas supply unit 250 also plays a role of accommodating the second gas. The second gas supply unit 250 supplies, for example, nitrogen gas to the second chamber 200 as the second gas. The second gas is turned into plasma in the second plasma generation region, reacts with the particles knocked out from the target T1, and is formed on the substrate S1. The second gas may be other reactive gas. In addition, other inert gas may be used depending on the material to be formed.

  The second gas supply pipe 260 is a flow path for supplying the second gas from the second gas supply unit 250 to the plasma generator 230.

1-3. Partition Unit The partition unit 300 partitions the first chamber 100 and the second chamber 200 as described above. The partition part 300 includes a wall 310, a top plate 320, a cylindrical part 330, and an opening member 340. The wall 310 and the top plate 320 are for partitioning the first chamber 100 and the second chamber 200.

2. Cylindrical part and opening member The cylindrical part 330 is a cylindrical member that protrudes toward the substrate support part 210. The cylindrical portion 330 is disposed at a position between the target accommodating portion 110 and the substrate support portion 210. The substrate S1 and the target T1 supported by the substrate support part 210 are included in the cylindrical shape when it is assumed that the cylindrical part 330 is extended. Therefore, the cylindrical portion 330 does not prevent the Ga radicals jumping out from the target T1 from moving toward the substrate S1. The cylindrical portion 330 has a first opening end 331. The first opening end 331 is one of the opening ends of the cylindrical portion 330. The first opening end 331 faces the substrate S1.

  The opening member 340 is a plate-like member having a plurality of through holes. The opening member 340 has a plurality of through holes that cover the first opening end 331 of the cylindrical portion 330 and communicate the first chamber 100 and the second chamber 200. The opening member 340 is disposed at a position between the target housing part 110 and the substrate support part 210.

  FIG. 2 is a plan view showing the through hole 341 of the opening member 340. As shown in FIG. 2, the through holes 341 of the opening member 340 are arranged in a honeycomb shape on the surface of the opening member 340. The through hole 341 of the opening member 340 is circular. The through holes 341 are regularly arranged on a line connecting the target T1 and the substrate S1.

  The opening ratio of the opening member 340 is 30% or more and 50% or less. The inner diameter of the through hole 341 of the opening member 340 is 1 mm or more. This is because if the inner diameter of the through hole 341 of the opening member 340 is less than 1 mm, a substance containing Ga may block the through hole 341. Since the size of the through hole 341 is sufficient, the Ga radical that has jumped out of the target T1 passes through the through hole 341 of the opening member 340 and reaches the surface of the substrate S1.

  The distance between the opening member 340 and the substrate S1 is 20 mm or less. This is to prevent the target particles from colliding with the gas in the second chamber 200 as much as will be described later. Preferably, the distance between the opening member 340 and the substrate S1 is 10 mm or less. In order to allow a gas containing nitrogen atoms to pass between the opening member 340 and the substrate S1, the distance between the opening member 340 and the substrate S1 is preferably 2 mm or more.

3. Number of collisions between target particles and gas particles The number of collisions N1 between target particles and gas particles in the second chamber 200 depends on the internal pressure P in the second chamber 200 and the distance T between the opening member 340 and the substrate S1. Dependent. The number of collisions N1 is proportional to the product of the internal pressure P and the distance T. Therefore, when the following equation is satisfied, the number of collisions between the target particles and the gas particles in the second chamber 200 is small.
4 (mm · Pa) ≤ P · T ≤ 40 (mm · Pa)
P: Internal pressure in the second chamber
T: Distance between the opening member and the substrate

More preferably, the following formula is satisfied.
10 (mm · Pa) ≤ P · T ≤ 20 (mm · Pa)

4). GaN Layer Formation Method A GaN layer formation method will be described. Here, a case where a sapphire substrate is used as the substrate S1 will be described. However, another substrate may be used instead of the sapphire substrate. Here, the target T1 is Ga. The first gas is argon gas. The second gas is nitrogen gas. The substrate S1 may have an AlN buffer layer on the surface. Under such conditions, a GaN layer is formed on the sapphire substrate. Thus, the GaN layer deposition method of this embodiment is also a method of manufacturing a GaN layer on a sapphire substrate.

  The first potential applying unit 140 applies a high frequency potential to the target T1. At that time, the first gas supply unit 150 supplies the first gas to the first chamber 100. Therefore, plasma is generated around the target T1. A region between the target storage unit 110 and the partition unit 300 in the first chamber 100 is a first plasma generation region. As described above, the first chamber 100 includes the first plasma generation region. The plasma generated in the first plasma generation region irradiates the target T1 with ions or particles derived from the first gas and causes the particles to jump out of the target T1.

  The second potential applying unit 240 applies a high frequency potential to the plasma generator 230. At that time, the second gas supply unit 250 supplies the second gas to the second chamber 200. Therefore, plasma is generated inside the plasma generator 230. The second gas is ionized when passing through the inside of the plasma. And the 2nd gas supplied to the 2nd chamber 200 is supplied between the board | substrate support part 210 and the division part 300 in the state of plasma gas. Therefore, the area between the substrate support part 210 and the partition part 300 in the second chamber 200 is a second plasma generation area. As described above, the second chamber 200 includes the second plasma generation region. The plasma lying in the second plasma generation region has particles derived from nitrogen atoms. The particles derived from nitrogen atoms are nitrogen ions, nitrogen radicals, or excited states thereof.

  The Ga particles that have jumped out of the target T1 pass through the cylindrical portion 330 and pass through the through hole 341 of the opening member 340. That is, Ga particles enter the second chamber 200 from the first chamber 100 and fly toward the substrate S1. Since the Ga particles hardly collide with nitrogen gas or argon gas, they enter the substrate S1 with high kinetic energy. Therefore, the Ga particles that have reached the substrate S1 suitably move around on the substrate S1.

  On the other hand, particles derived from nitrogen atoms diffuse into the space where the substrate S1 and the opening member 340 face each other. Particles derived from nitrogen atoms combine with Ga particles moving around on the substrate S1, and a GaN layer is formed.

  The internal pressures of the first chamber 100 and the second chamber 200 are in the range of 0.1 Pa to 20 Pa. The substrate temperature is, for example, 300 ° C. or higher and 800 ° C. or lower. Of course, a numerical range other than the above may be used.

5. Effects of the present embodiment 5-1. Kinetic energy of Ga radical In this embodiment, the distance between the opening member 340 and the substrate S1 is sufficiently small. For this reason, the number of times that Ga radicals that have jumped out of the target T1 collide with argon gas and nitrogen gas in the second chamber 200 is small. Therefore, the kinetic energy when the Ga radical collides with the substrate S1 is sufficiently large. Therefore, Ga radicals can move around on the surface of the substrate S1 or the surface of the semiconductor layer. As a result, a semiconductor layer having excellent uniform crystallinity is formed in the plane. Here, when the kinetic energy of the Ga radical is small, the Ga radical cannot sufficiently move around the surface of the substrate S1. In that case, GaN is likely to grow three-dimensionally with Ga particles close to a stopped state as a nucleus, and it is difficult to grow a semiconductor layer having excellent crystallinity.

5-2. Inhibition of GaN synthesis in space In this embodiment, the distance between the opening member 340 and the substrate S1 is sufficiently small. Therefore, the number of collisions between Ga radicals and particles containing nitrogen atoms is small. That is, the ratio of the Ga radicals and the nitrogen atom-containing particles reacting to produce a GaN compound at a position away from the substrate S1 is small. Further, since the plate surface of the substrate S1 faces vertically downward, such a GaN compound is difficult to deposit on the substrate S1.

5-3. Isolation of Particles Containing Nitrogen Atoms The film forming apparatus 1000 of this embodiment has an opening member 340. Portions other than the through-hole 341 in the opening member 340 prevent permeation of particles derived from nitrogen atoms. That is, particles derived from nitrogen atoms are unlikely to enter the first chamber 100. Therefore, collision of Ga particles that have jumped out of the target T <b> 1 with particles derived from nitrogen atoms in the first chamber 100 is suppressed. Moreover, it can suppress that target T1 is nitrided.

5-4. Selection of Gas In the present embodiment, the first chamber 100 for ejecting particles from the target T1 and the second chamber 200 for forming a film on the substrate S1 are provided separately. Therefore, different gases can be supplied to the first chamber 100 having the target accommodating portion 110 and the second chamber 200 having the substrate support portion 210. Therefore, a gas that does not easily react with the target T1 can be selected and supplied into the first chamber 100 in which the target T1 is accommodated. Although there is a possibility that gas flows from the second chamber 200 into the first chamber 100 through the through hole 341, the flow rate is very small. Thereby, it can suppress that target T1 reacts with supply gas on the surface of target T1.

5-5. Separation of Plasma Generation Region In the present embodiment, a first plasma generation region for ejecting particles from the target T1 and a second plasma generation region containing a plasma gas used for film formation are generated separately. To do. Therefore, the plasma in the first plasma generation region and the plasma in the second plasma generation region can be controlled separately. For example, by increasing the power for generating the first plasma generation region, the number of particles from the target T1 can be increased and the kinetic energy of the particles can be increased. Therefore, there is a possibility that the number of particles from the target T1 and the number of particles derived from the second gas can be adjusted. Therefore, improvement in sputtering yield and improvement in crystallinity of the thin film are expected.

6). Modification 6-1. Shape of the cylindrical portion The cylindrical portion 330 of the present embodiment has a cylindrical shape. The cylindrical portion 330 may be a polygonal cylindrical shape. This is because it is not necessary to prevent the Ga particles that have jumped out of the target T1 from flying toward the substrate S1.

6-2. Through hole The shape of the through hole 341 of the opening member 340 is circular. The shape of the through hole 341 may be a polygon larger than a circle having a diameter of 1 mm. Further, the arrangement of the through holes 341 may be other than the honeycomb shape.

6-3. Multiple First Chambers In the present embodiment, the film forming apparatus 1000 has one first chamber 100. However, the film forming apparatus 1000 may have a plurality of first chambers 100. For example, the film formation apparatus 1000 may include a first chamber 100 having a Ga target and a first chamber 100 having an Al target. In that case, an AlGaN layer can be formed on the substrate S1. Needless to say, the film forming apparatus 1000 may include three or more first chambers 100.

6-4. Shutter The film formation apparatus 1000 may have a shutter that opens and closes the through hole 341. The shutter is an opening / closing part that brings the through-hole 341 into either an open state or a closed state. The shutter is effective when it has a plurality of first chambers 100 as described above. That is, the plurality of first chambers 100 each have a through hole and a shutter. Thereby, AlN can be formed on the substrate S1 from the Al target, GaN can be formed from the Ga target, and AlGaN can be formed from the Al target and the Ga target.

6-5. Second gas containing hydrogen gas The second gas may contain hydrogen gas. The second gas may be a mixed gas of nitrogen gas and hydrogen gas. In this case, NH is generated by the plasma generator 230. In this case, NH is considered to contribute to the formation of the GaN layer.

6-6. Internal pressure of first chamber and second chamber The internal pressure of the second chamber 200 may be lower than the internal pressure of the first chamber 100. This is because the particles in the second plasma generation region inside the second chamber 200 are less likely to flow into the first chamber 100.

6-7. First Potential Applying Unit In the present embodiment, the first potential applying unit 140 applies a high-frequency potential to the target accommodating unit 110. The first potential applying unit 140 may apply a pulse potential to the target accommodating unit 110. Further, the first potential applying unit 140 may apply a constant potential to the target accommodating unit 110. In this case, a DC voltage is applied between the target T1 and the partition unit 300.

6-8. Substrate Support Unit The substrate support unit 210 may be rotatable. Further, the substrate support unit 210 may include a third potential applying unit that applies a high-frequency potential or a constant potential.

6-9. Type of gas The second gas may contain argon gas. Thus, the first gas and the second gas may be a mixed gas of two or more kinds of gases. However, it is preferable that the first gas does not include a gas that easily reacts with the target T1. The first gas is for releasing particles from the target T1. The second gas includes particles that react with particles emitted from the target T1. Therefore, it may be appropriately selected according to the type of material to be deposited.

6-10. Plasma Generation Device A case where an ICP device is used as the plasma generation device 230 will be described. In that case, an ion filter may be attached to the ICP device. Thereby, it can suppress that nitrogen ion damages board | substrate S1.

6-11. Magnet of target accommodating part support part In this embodiment, the target accommodating part support part 120 has a magnet. The target accommodating part support part 120 does not need to have a magnet.

6-12. Particle Timing Control The particles supplied from the first chamber 100 and the particles supplied from the second chamber 200 may be controlled. For example, the second potential application unit 240 does not generate plasma in the second plasma generation region during the period in which the first potential application unit 140 generates plasma in the first plasma generation region, The second potential applying unit 240 generates plasma in the second plasma generating region within a period in which the potential applying unit 140 does not generate plasma in the first plasma generating region. That is, plasma is generated alternately in the first plasma generation region and the second plasma generation region. As a result, particles from the first chamber 100 toward the substrate S1 and particles from the second chamber 200 toward the substrate S1 are alternately generated. The timing at which the first gas supply unit 150 supplies the first gas and the timing at which the second gas supply unit 250 supplies the second gas may be alternately shifted.

6-13. Substrate Type The substrate S1 of this embodiment is a sapphire substrate. The substrate S1 may be another substrate such as a Si (111) substrate.

6-14. Combination The above modification examples may be freely combined.

7). Summary of the Present Embodiment A film forming apparatus 1000 according to the present embodiment includes a first chamber 100 that accommodates the target accommodating portion 110 and a second chamber 200 that accommodates the substrate support portion 210. The distance between the first chamber 100 and the second chamber 200 is sufficiently small. For this reason, the Ga radicals jumping out of the target T1 do not collide so much with argon gas and nitrogen gas. Therefore, the Ga radical collides with the substrate S1 with a high kinetic energy. Thereby, a semiconductor having excellent crystallinity is formed.

(Second Embodiment)
A second embodiment will be described. The film forming apparatus of the second embodiment is a CVD apparatus. The mechanical configuration of the film forming apparatus of the second embodiment is the same as the mechanical configuration of the film forming apparatus 1000 of the first embodiment. The second embodiment is different from the first embodiment in the types of the first gas and the second gas.

1. The first gas and the second gas the first gas supply unit 150 supplies a gas containing argon gas and chlorine gas (Cl ₂₎ as the first gas. The second gas supply unit 250 supplies a gas containing nitrogen gas and hydrogen gas as the second gas. Here, the target T1 is a Ga target.

  Chlorine gas is turned into plasma in the first plasma generation region. Then, particles derived from chlorine atoms (including chlorine molecules, chlorine atoms and chlorine radicals) collide with the Ga target. The Ga target reacts with particles derived from chlorine atoms to generate GaClx (Ga chloride). Then GaClx particles pop out. The jumped GaClx particles fly toward the substrate S1. The GaClx particles react with particles derived from nitrogen atoms in the second plasma generation region. Thereby, a GaN layer is formed on the substrate S1.

  Note that particles contained in the second plasma generation region break the bond between Ga atoms and Cl atoms. Therefore, the GaN layer on the substrate S1 contains almost no Cl atoms.

2. Flow rate of chlorine gas The flow rate of chlorine gas in the first gas is preferably 0.1% or more and 1% or less by volume ratio.

3. Modification 3-1. First Gas As the first gas, a gas containing other halogen such as bromine may be used instead of chlorine gas. In that case, a reaction product of Ga and halogen is transported to the substrate S1. The first gas may contain an organic molecule such as methyl.

3-2. Second gas Oxygen may be used as the second gas. In this case, a gallium oxide film is formed on the substrate S1.

3-3. Combination The above modification examples may be freely combined. You may combine 1st Embodiment and its modification, 2nd Embodiment, and its modification.

A-1. Type of substrate A sapphire substrate on which an AlN buffer layer has been formed was used as the substrate S1.

A-2. Film forming conditions of the film forming apparatus Ga was used as the target T1. Therefore, granular Ga was heated and melted at 100 ° C. and cooled with cooling water from the cooling unit 130 during film formation. The temperature of the cooling water was 10 ° C. As the first gas, 39.8 sccm of argon gas and 0.2 sccm of chlorine gas were flowed. As the second gas, 9 sccm of nitrogen gas and 1 sccm of hydrogen gas were flowed. The power of the first potential applying unit 140 was 100W. The frequency of the first potential application unit 140 was 13.56 MHz. The plasma generator 230 is an ICP device. The power of the ICP device was 1000W. The frequency of the ICP device was 13.56 MHz. The internal pressure of the first chamber 100 and the second chamber 200 was 2 Pa. The temperature of the heating unit 220, that is, the substrate temperature was 600 ° C. The film formation time was 1 hour.

A-3. Deposition Rate FIG. 3 is a graph showing the relationship between the distance between the opening member 340 and the substrate S1 and the GaN deposition rate. The horizontal axis in FIG. 3 is the distance between the opening member 340 and the substrate S1. The vertical axis in FIG. 3 represents the film formation rate (μm / h). As shown in FIG. 3, the deposition rate is about 1 μm / h.

A-4. Crystallinity FIG. 4 is a graph showing the relationship between the distance between the opening member 340 and the substrate S1 and the crystallinity of GaN. The horizontal axis in FIG. 4 is the distance between the opening member 340 and the substrate S1. The vertical axis in FIG. 4 is the FWHM of GaN (0002) in X-ray diffraction. FIG. 4 shows the result of the X-ray rocking curve. As shown in FIG. 4, when the distance between the opening member 340 and the substrate S1 is 10 mm, the FWHM is 0.85. When the distance between the opening member 340 and the substrate S1 is 20 mm, the FWHM is 1.03. When the distance between the opening member 340 and the substrate S1 is 30 mm, the FWHM is 1.9.

  Thus, when the distance between the opening member 340 and the substrate S1 is 20 mm or less, the FWHM is about 1.05 or less. Therefore, the distance between the opening member 340 and the substrate S1 is preferably 20 mm or less.

A-5. Surface Morphology FIG. 5 is a scanning photomicrograph showing the relationship between the distance between the aperture member 340 and the substrate S1 and the surface morphology of GaN. FIG. 5A is a cross-sectional SEM image when the distance between the opening member 340 and the substrate S1 is 30 mm. FIG. 5B is a cross-sectional SEM image when the distance between the opening member 340 and the substrate S1 is 20 mm. FIG. 5C is a cross-sectional SEM image when the distance between the opening member 340 and the substrate S1 is 10 mm. FIG. 5D is a surface SEM image when the distance between the opening member 340 and the substrate S1 is 30 mm. FIG. 5E is a surface SEM image when the distance between the opening member 340 and the substrate S1 is 20 mm. FIG. 5F is a surface SEM image when the distance between the opening member 340 and the substrate S1 is 10 mm.

  As shown in FIGS. 5D to 5F, the smaller the distance between the opening member 340 and the substrate S1, the better the surface morphology. That is, the surface morphology of GaN is good when the distance between the opening member 340 and the substrate S1 is 10 mm or less.

A-6. Summary of Experiment As described above, when the distance between the opening member 340 and the substrate S1 is 20 mm or less, the FWHM of GaN is 1.05 or less. When the distance between the opening member 340 and the substrate S1 is 10 mm or less, the surface morphology of GaN is good.

B. Appendix The film forming apparatus according to the first aspect includes a first chamber, a second chamber, and a partition section that divides the first chamber and the second chamber. The first chamber has a target accommodating portion that accommodates the target. The second chamber has a substrate support portion that supports the substrate. The partition portion has an opening member having a first opening end facing the substrate, a plurality of through holes that cover the first opening end of the cylindrical portion and communicate the first chamber and the second chamber. And having. The target accommodating portion is disposed at a position facing the substrate support portion. The opening member is disposed at a position between the target accommodating portion and the substrate support portion.

In the film forming apparatus according to the second aspect, the internal pressure of the second chamber and the distance between the opening member and the substrate are expressed by the following formula 4 (mm · Pa) ≦ P · T ≦ 40 (mm · Pa)
P: Internal pressure of second chamber (Pa)
T: Distance between opening member and substrate (mm)
Meet.

  In the film forming apparatus according to the third aspect, the distance between the substrate supported by the substrate support portion and the opening member is 20 mm or less.

  In the film forming apparatus according to the fourth aspect, the substrate and the target supported by the substrate support portion are included in a cylindrical shape when the cylindrical portion is extended.

  The film forming apparatus according to the fifth aspect includes a first potential applying unit that applies a potential to the target accommodating unit.

  The film-forming apparatus in a 6th aspect has a 1st gas supply part which supplies 1st gas to a 1st chamber, and a 2nd gas supply part which supplies 2nd gas to a 2nd chamber. .

  The film forming apparatus according to the seventh aspect includes a plasma generating apparatus that converts the second gas supplied from the second gas supply unit into plasma.

DESCRIPTION OF SYMBOLS 1000 ... Film-forming apparatus 1001 ... Case 100 ... 1st chamber 110 ... Target accommodating part 120 ... Target accommodating part support part 130 ... Cooling part 140 ... 1st electric potential provision part 150 ... 1st gas supply part 160 ... 1st Gas supply pipe 200 ... second chamber 210 ... substrate support part 220 ... heating part 230 ... plasma generator 240 ... second potential applying part 250 ... second gas supply part 260 ... second gas supply pipe 270 ... exhaust Mouth 300 ... partition part 310 ... wall 330 ... cylindrical part 340 ... opening member S1 ... substrate T1 ... target

Claims (7)

The first room,
The second room,
A partition section that partitions the first chamber and the second chamber;
In a film forming apparatus having
The first chamber is
Having a target accommodating portion for accommodating the target;
The second chamber is
Having a substrate support for supporting the substrate;
The partition is
A cylindrical portion having a first opening end facing the substrate;
An opening member that covers the first opening end of the cylindrical portion and has a plurality of through holes that communicate the first chamber and the second chamber;
The target container is
It is arranged at a position facing the substrate support part,
The opening member is
A film forming apparatus, wherein the film forming apparatus is disposed at a position between the target accommodating portion and the substrate supporting portion. The film forming apparatus according to claim 1,
The internal pressure of the second chamber and the distance between the opening member and the substrate are as follows: 4 (mm · Pa) ≦ P · T ≦ 40 (mm · Pa)
P: Internal pressure of second chamber (Pa)
T: Distance between opening member and substrate (mm)
The film-forming apparatus characterized by satisfy | filling. The film forming apparatus according to claim 1,
The distance between the substrate supported by the substrate support portion and the opening member is
A film forming apparatus having a thickness of 20 mm or less. In the film-forming apparatus of any one of Claim 1- Claim 3,
The substrate and the target supported by the substrate support unit are:
A film forming apparatus, wherein the film forming apparatus is included in a cylindrical shape when the cylindrical shape portion is extended. In the film-forming apparatus of any one of Claim 1- Claim 4,
A film forming apparatus comprising a first potential applying unit that applies a potential to the target accommodating unit. In the film-forming apparatus of any one of Claim 1- Claim 5,
A first gas supply unit for supplying a first gas to the first chamber;
A second gas supply unit for supplying a second gas to the second chamber;
A film forming apparatus comprising: In the film-forming apparatus of Claim 6,
A film forming apparatus, comprising: a plasma generating apparatus that converts the second gas supplied from the second gas supply unit into plasma.