Manufacturing method of laminate, manufacturing apparatus of laminate, laminate and semiconductor device

Abstract

The present invention is a method for manufacturing a layered body including a semiconductor film having a corundum crystal structure, wherein the method is characterized by including: a step for placing a substrate on a stage; a step for heating the substrate; a step for atomizing a raw material solution for film formation; a step for forming a mixed gas by mixing the atomized raw material solution for film formation and a carrier gas; and a step for forming a film by supplying the mixed gas to the substrate. The method for manufacturing the layered body is also characterized in that the surface roughnesses Ra of a surface of the stage that contacts the substrate and of a surface of the substrate that contacts the stage are 0.5 μm or lower. The foregoing provides a layered body manufacturing method with which it is possible to make a thick corundum crystal thin film (semiconductor film having a corundum structure) that has excellent crystal orientation and high quality in a stable manner .

Description

[Technical field]

[0001] The present invention relates to a method and apparatus for manufacturing a laminate, a laminate, and a semiconductor device. [Background technology]

[0002] Mist Chemical Vapor Deposition (Mist CVD) is known as a method for forming a highly crystalline corundum-type crystal thin film on a substrate. Patent Document 1 describes a method for forming an α-Ga2O3 film on a sapphire substrate by misting a solution using a gallium acetylacetonate complex and supplying the mist to the substrate placed in a narrow space (fine channel) in a reactor. Patent Document 2 describes a method for forming an α-Ga2O3 film by placing a sapphire substrate on a hot plate installed in a film formation chamber and supplying a mist of a raw material solution made of gallium bromide from a nozzle installed above the substrate to the substrate. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2013-028480 A [Patent Document 2] JP 2020-107636 A Summary of the Invention [Problem to be solved by the invention]

[0004] When corundum-type crystal thin films are used as semiconductor devices, they generally require a thickness of several hundred nm or more, and when used as power devices, a thickness of 1 μm or more is required. However, gallium oxide-based thin films formed by the mist CVD method have a problem in that the crystal quality decreases significantly as the film thickness increases. This problem is particularly noticeable when the film thickness is 1 μm or more.

[0005] The present invention has been made to solve the above problems, and aims to provide a method for manufacturing a laminate capable of stably forming a thick film of a corundum type crystal thin film (a semiconductor film having a corundum type crystal structure) having excellent crystal orientation and high quality. Another aim of the present invention is to provide a high quality laminate suitable for manufacturing a semiconductor device. [Means for solving the problem]

[0006] The present invention has been made in order to achieve the above object, A method for producing a laminate including a semiconductor film having a corundum type crystal structure, comprising the steps of: placing a substrate on a stage; heating the substrate; A step of atomizing a film-forming raw material solution; mixing the atomized film-forming raw material solution with a carrier gas to form a mixture; supplying the gas mixture to the substrate to form a film; Including, The present invention provides a method for manufacturing a laminate in which the surface of the stage that comes into contact with the base and the surface of the base that comes into contact with the stage have a surface roughness Ra of 0.5 μm or less.

[0007] With this method, even if the film thickness is increased, it is possible to stably manufacture a laminate including a semiconductor film having a high-quality corundum crystal structure with excellent crystal orientation. In addition, damage to the transport system and the substrate carrier caused by the back surface of the substrate is greatly reduced, so that dust generation in the device is suppressed, and the degree of freedom in the materials of the transport system and the substrate carrier is increased, so that it is possible to stably and inexpensively manufacture a laminate including a semiconductor film having a high-quality corundum crystal structure.

[0008] At this time, it is preferable that the waviness Wa of the contact surface of the stage with the base body and the contact surface of the base with the stage be 50 μm or less.

[0009] In this way, the contact area with the substrate is increased, thereby improving thermal conduction, and the temperature drop on the substrate surface during film formation due to the film-forming raw material mist is not significant, so that the crystal orientation of the semiconductor film does not deteriorate, allowing for the stable production of high-quality laminates.

[0010] In this case, it is preferable that the stage is heated in the step of heating the base body.

[0011] In this way, the temperature of the base can be easily maintained, and a high-quality laminate can be stably produced.

[0012] In this case, it is preferable to use a substrate having a thickness of 50 μm or more and 5000 μm or less.

[0013] In this way, the temperature of the substrate can be maintained more easily, making it possible to form a laminate with a greater thickness.

[0014] In this case, it is preferable to use a single crystal substrate.

[0015] In this way, a laminate of even higher quality can be obtained.

[0016] In this case, it is preferable that the step of placing the substrate on the stage further includes the step of vacuum fixing the substrate to the stage, and the degree of vacuum is 80 kPa or less.

[0017] In this way, the substrate can be held and heated stably, and a laminate of even higher quality can be obtained.

[0018] The present invention also provides an apparatus for manufacturing a laminate including a semiconductor film having a corundum type crystal structure, comprising: a stage on which a substrate is placed; A heating means for heating the substrate; an atomizing means for atomizing a film-forming raw material solution; a gas mixture supplying means for mixing the atomized film-forming raw material solution with a carrier gas and supplying the mixture to the substrate, The surface roughness Ra of the surface of the stage that comes into contact with the base is 0.5 μm or less.

[0019] With such a manufacturing device, even if the film thickness is increased, it is possible to stably manufacture a laminate including a semiconductor film having a high-quality corundum crystal structure with excellent crystal orientation. In addition, damage to the transport system and the substrate carrier caused by the rear surface of the substrate is greatly reduced, so that dust generation in the device is suppressed, and the degree of freedom in the materials of the transport system and the substrate carrier is increased, so that it is possible to more stably and inexpensively manufacture a laminate including a semiconductor film having a high-quality corundum crystal structure.

[0020] In this case, it is preferable that the waviness Wa of the contact surface of the stage with the base body is 50 μm or less.

[0021] In this way, the contact area with the substrate is increased, thereby improving thermal conduction, and the temperature drop on the substrate surface during film formation due to the film-forming raw material mist is not significant, so that the crystal orientation of the semiconductor film does not deteriorate, making it possible to stably produce a high-quality laminate.

[0022] The present invention also provides a laminate, Provided is a laminate comprising a substrate and a semiconductor film having a corundum-type crystal structure on a first main surface of the substrate directly or via another layer, the second main surface of the substrate being opposite to the first main surface and having a surface roughness Ra of 0.5 μm or less.

[0023] Such a laminate has a corundum type crystal structure, is of high quality, and is suitable for manufacturing semiconductor film devices.

[0024] In this case, the thickness of the substrate is preferably 50 μm or more and 5000 μm or less.

[0025] In this way, the temperature of the substrate can be easily maintained, and therefore a laminate having a larger thickness can be obtained.

[0026] In this case, the substrate is preferably a single crystal.

[0027] In this way, a laminate of even higher quality can be obtained.

[0028] In this case, the semiconductor film preferably has a thickness of 1 μm or more.

[0029] Such a laminated body can provide a higher degree of freedom in designing a semiconductor device.

[0030] The present invention also provides a semiconductor device including at least a semiconductor layer and an electrode, the semiconductor layer including at least a part of the above-described laminate.

[0031] This makes it possible to provide a high-performance semiconductor device. Effect of the Invention

[0032] As described above, according to the present invention, a method for manufacturing a laminate capable of stably forming a thick film of a high-quality corundum-type crystal thin film can be provided. Also, according to the present invention, a high-quality laminate having excellent crystal orientation and suitable for manufacturing a semiconductor device can be provided. Also, according to the present invention, a high-performance semiconductor device can be provided. [Brief description of the drawings]

[0033] [Figure 1] FIG. 1 is a diagram showing one embodiment of a film forming apparatus used in a film forming method according to the present invention. [Diagram 2] FIG. 2 is a diagram illustrating one embodiment of a laminate according to the present invention. [Diagram 3] 1A to 1C are diagrams illustrating one embodiment of a semiconductor device according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0034] As described above, there has been a demand for a method for manufacturing a laminate capable of stably forming a thick film including a high-quality corundum-type crystal thin film having excellent crystal orientation, as well as a high-quality laminate suitable for manufacturing semiconductor devices.

[0035] The present inventors have been intensively studying the above-mentioned problems, and have found that the above-mentioned problems are caused by the low thermal conductivity of gallium oxide-based thin film, and the film formation in mist CVD is performed through low-temperature droplets, which causes a relatively large temperature drop on the surface of the film during growth.Therefore, the present invention has been completed by finding that the method includes the steps of placing a substrate on a stage, heating the substrate, atomizing the film-forming raw material solution, mixing the atomized film-forming raw material solution with carrier gas to form a mixture, and supplying the mixture to the substrate to form a film, and by making the surface roughness Ra of the contact surface between the substrate and the stage and the contact surface between the substrate and the stage 0.5 μm or less, a laminate containing a corundum-type crystal thin film with high crystallinity and sufficient film thickness can be obtained.

[0036] That is, the present invention provides a method for producing a laminate including a semiconductor film having a corundum type crystal structure, comprising: placing a substrate on a stage; heating the substrate; A step of atomizing a film-forming raw material solution; mixing the atomized film-forming raw material solution with a carrier gas to form a mixture; supplying the gas mixture to the substrate to form a film; Including, This is a method for manufacturing a laminate, in which the surface of the stage that comes into contact with the base and the surface of the base that comes into contact with the stage have a surface roughness Ra of 0.5 μm or less.

[0037] The present inventors have also discovered a manufacturing apparatus for a laminate including a semiconductor film having a corundum type crystal structure, comprising: a stage on which a substrate is placed; A heating means for heating the substrate; an atomizing means for atomizing a film-forming raw material solution; a gas mixture supplying means for mixing the atomized film-forming raw material solution with a carrier gas and supplying the mixture to the substrate, The inventors discovered that by designing the stage so as to have a surface roughness Ra of 0.5 μm or less on the contact surface between the stage and the base, it is possible to produce a high-quality laminate suitable for semiconductor device manufacturing, thereby completing the present invention.

[0038] The present inventors have also discovered a laminate comprising: The inventors have found that a laminate comprising a base and a semiconductor film having a corundum-type crystal structure formed directly or via another layer on a first main surface of the base, in which a second main surface opposite the first main surface of the base has a surface roughness Ra of 0.5 μm or less, can provide a high-quality laminate suitable for manufacturing semiconductor devices, and have completed the present invention.

[0039] The present invention will be described in detail below, but the present invention is not limited thereto.

[0040] The following description will be given with reference to the drawings.

[0041] (Laminate) 2 is a diagram illustrating one embodiment of the laminate of the present invention. The laminate 200 of the present invention is composed of a base 201, an underlayer 202 formed directly on the base 201, and a crystal layer 203 having a corundum structure. The base 201 has a first main surface 201a and a second main surface 201b opposite thereto, and the surface roughness Ra of the second main surface is 0.5 μm or less. The crystal layer 203 corresponds to the semiconductor film of the laminate of the present invention.

[0042] The substrate 201 is not particularly limited as long as it has a first main surface and a second main surface opposite thereto, and can support a film to be formed, and may be similar to the substrate 130 in Fig. 1 described later. In particular, a single crystal substrate is preferable.

[0043] The shape of the substrate 201 may be any shape having a first main surface and a second main surface opposite thereto, and may be, for example, a plate-like shape such as a flat plate or a disk, a rod-like shape, a column-like shape, a prism-like shape, a tube-like shape, a ring-like shape, or the like, but is preferably a plate-like shape. In the present invention, the surface roughness Ra of the second main surface (also called the back surface) located opposite the first main surface of the substrate on which the film is formed is 0.5 μm or less. More preferably, the waviness Warp (hereinafter referred to as Wa) is 50 μm or less. The smaller the surface roughness Ra, the more preferable, and the lower limit is not particularly limited, but may be, for example, 0.1 nm or more. The surface roughness Ra may be measured at one or more arbitrary points on the main surface, with a measurement length of, for example, 10 μm or more. The smaller the waviness Wa, the more preferable, and the lower limit is not particularly limited, but may be, for example, 0.5 μm or more. The waviness Wa may be measured on one or more arbitrary straight lines on the main surface of the substrate 201, which are appropriately determined according to the shape of the substrate. For example, in the case of a disk-shaped substrate having a diameter of 10 cm, any length on two straight lines intersecting at right angles at the center of the substrate can be the measurement length. The surface roughness Ra and the waviness Wa refer to values ​​calculated based on JIS B 0601 using the results of surface shape measurement by a non-contact measurement method using a laser microscope or a confocal microscope, such as a stylus method, an atomic force microscope (AFM) method, or an optical interference method, a confocal method, or an image synthesis method using focus movement. Such a laminate can be processed by irradiating light from the second main surface of the substrate with high quality, and the design freedom of the semiconductor device is increased. In addition, as described later, by forming a film in combination with a stage having a smooth substrate mounting surface, a laminate having a high-quality semiconductor film with excellent crystal orientation can be obtained even if the film is formed thickly. Such a smooth substrate surface can be easily obtained, for example in the case of sapphire, by lapping the surface of the substrate obtained by processing the crystal with diamond abrasive grains and then providing a mirror finish by chemical mechanical polishing (CMP) using colloidal silica.

[0044] In addition, the area of ​​the first main surface, the surface on which the semiconductor film is formed, is 5 cm 2 More than 10cm, preferably 2A substrate having a thickness of 50 to 5000 μm or more, more preferably 100 to 2000 μm, can be suitably used. If the thickness is 50 μm or more, it is easy to support the semiconductor film, and if the thickness is 5000 μm or less, not only does the substrate cost decrease, but the number of substrates processed per batch increases in the semiconductor device manufacturing process, improving productivity.

[0045] The crystal layer 203 is not particularly limited as long as it is a semiconductor film having a corundum crystal structure. The corundum crystal is a metal oxide crystal, and the metal may contain, for example, Al, Ti, V, Cr, Fe, Co, Ni, Ga, Rh, In, or Ir as a main component. The crystal layer 203 may be polycrystalline, but is preferably single crystalline. The composition of the crystal layer 203 is preferably such that the total atomic ratio of gallium, indium, aluminum, and iron in the metal elements contained in the thin film is 0.5 or more, and more preferably the atomic ratio of gallium in the metal elements is 0.5 or more. In addition, it is preferable to further set the film thickness to 1 μm or more, since this film is more suitable for semiconductor devices. The upper limit of the film thickness is not particularly limited, but can be, for example, 20 μm or less. The film thickness of each layer of the laminate can be set to any thickness by adjusting the film formation time.

[0046] The crystal layer 203 may contain a dopant element. The dopant is not particularly limited, and examples thereof include n-type dopants such as tin, silicon, germanium, titanium, zirconium, vanadium, and niobium, and p-type dopants such as copper, silver, cobalt, iridium, rhodium, magnesium, and nickel. The concentration of the dopant is appropriately adjusted according to the design of the intended semiconductor device, and may be, for example, 1×10 16 / cm 3 ~1×10 22 / cm 3 It may be.

[0047] The underlayer 202 may be, for example, a semiconductor film having a corundum structure with a different composition from that of the crystal layer 203, a crystal thin film having a structure other than the corundum structure, or an amorphous thin film.

[0048] Depending on the purpose, the underlayer 202 may be a stress relaxation layer for relieving lattice mismatch or thermal stress between the base 201 and the crystal layer 203, or may be a sacrificial layer for peeling off the crystal layer 203 from the base 201 in a later step. For example, when forming an α-Ga2O3 film on an Al2O3 substrate, the underlayer (stress relaxation layer) 202 may be, for example, (Al x Ga 1-x )2O3 (0≦x≦1), with the value of x decreasing from the substrate 201 side toward the crystal layer 203 side. As the sacrificial layer, a material having a smaller band gap than the crystal layer 203, or a material having a property of being soluble in water, acid, alkali, or other solutions, alcohols, or ketones is preferably used, and may be, for example, a crystal film or amorphous film of an oxide containing Si, V, Cr, Fe, Co, Ni, Zn, Ge, Rh, In, Sn, or Ir, and more preferably Fe2O3, Co2O3, Ni2O3, Rh2O3, In2O3, Ir2O3, or a mixed crystal thereof. In addition, the underlayer 202 may or may not contain a dopant.

[0049] 2 shows an example in which one underlayer 202 and one crystal layer 203 are formed on the base 201, but the present invention is not limited to this, and either or both of the underlayer 202 and the crystal layer 203 may be formed in multiple layers. The crystal layer 203 may be formed directly on the base 201 without forming the underlayer 202. Although not shown in the figure, a crystalline or amorphous conductor layer, insulator layer, etc. may be further laminated on the crystal layer 203.

[0050] In the laminate of the present invention, the semiconductor film or the laminate including the semiconductor film may be peeled off from the substrate. The peeling means is not particularly limited and may be a known means. Examples of the peeling means include a means for peeling by applying mechanical impact, a means for peeling by applying heat and utilizing thermal stress, a means for peeling by applying vibration such as ultrasonic vibration, a means for peeling by etching, and a means for peeling by utilizing a change in the state of the film due to light absorption. If the film peeled off in this way has a sufficient thickness, it can also be made into a free-standing film.

[0051] (Semiconductor Device) The semiconductor device of the present invention includes at least a semiconductor layer and an electrode, and the semiconductor layer can include at least a part of the above-described laminate.

[0052] The semiconductor film in the laminate of the present invention has good crystal orientation and excellent electrical properties, and is industrially useful. Such a laminate can be suitably used in semiconductor devices, and is particularly useful in power devices. The semiconductor film formed as a part of the laminate may be used as it is (in the laminate state), or may be applied to a semiconductor device after peeling it off from the substrate by a known method.

[0053] In addition, semiconductor devices can be classified into horizontal elements (horizontal devices) in which an electrode is formed on one side of a semiconductor layer, and vertical elements (vertical devices) in which an electrode is formed on both the front and back sides of a semiconductor layer, and at least a part of the laminate of the present invention can be suitably used in both horizontal and vertical devices. In particular, at least a part of the laminate of the present invention is preferably used in a vertical device.

[0054] Examples of the semiconductor device include a Schottky barrier diode (SBD), a metal semiconductor field effect transistor (MESFET), a high electron mobility transistor (HEMT), a metal oxide semiconductor field effect transistor (MOSFET), a junction field effect transistor (JFET), an insulated gate bipolar transistor (IGBT), and a light emitting diode (LED).

[0055] In addition, in a semiconductor device using the laminate of the present invention, other layers (e.g., an insulating layer or a conductor layer) may be further included depending on the specifications and purpose, and the base layer may be added or omitted as appropriate.

[0056] A suitable example of a semiconductor device using the laminate of the present invention is shown in Fig. 3. Fig. 3 shows an example of a Schottky barrier diode (SBD). The Schottky barrier diode (SBD) 300 is a relatively lightly doped n-type - A relatively highly doped n-type semiconductor layer 301a + The n-type semiconductor layer 301b, the Schottky electrode 302, and the ohmic electrode 303 are provided. - Type semiconductor layers 301a and + The type semiconductor layer 301b is formed by using a part of the laminate of the present invention.

[0057] The material of the Schottky electrode 302 and the ohmic electrode 303 may be a known electrode material, and examples of the electrode material include metals such as aluminum, molybdenum, cobalt, zirconium, tin, niobium, iron, chromium, tantalum, titanium, gold, platinum, vanadium, manganese, nickel, copper, hafnium, tungsten, iridium, zinc, indium, palladium, neodymium, and silver, and alloys thereof; conductive metal oxide films such as silver oxide, tin oxide, zinc oxide, rhenium oxide, indium oxide, indium tin oxide (ITO), and indium zinc oxide (IZO); organic conductive compounds such as polyaniline, polythiophene, and polypyrrole, and mixtures and laminates thereof.

[0058] The Schottky electrode 302 and the ohmic electrode 303 can be formed by known means such as a vacuum deposition method or a sputtering method. More specifically, for example, when forming a Schottky electrode using two types of metals, a first metal and a second metal, the Schottky electrode can be formed by stacking a layer made of the first metal and a layer made of the second metal, and patterning the layer made of the first metal and the layer made of the second metal using a photolithography method.

[0059] When a reverse bias is applied to the Schottky barrier diode (SBD) 300, a depletion layer (not shown) -Since the ohmic electrode 303 extends into the Schottky electrode 301a, the SBD has a high breakdown voltage. When a forward bias is applied, electrons flow from the ohmic electrode 303 to the Schottky electrode 302. Therefore, the SBD according to the present invention is excellent for high breakdown voltage and large current applications, has a fast switching speed, and is excellent in breakdown voltage and reliability.

[0060] (Film forming equipment) The following description will be given with reference to the drawings.

[0061] FIG. 1 is a diagram for explaining one embodiment of the configuration of a film forming apparatus suitable for use in the manufacture of the laminate of the present invention. The film forming apparatus 100 suitable for use in the manufacture of the laminate of the present invention includes at least a raw material container 120 for atomizing a film forming raw material solution 121 to form a film forming raw material mist 122, a film forming chamber 131 for supplying the film forming raw material mist 122 to a substrate 130 to form a film on the substrate 130, a stage 135 for placing the substrate 130, and a heating means 132 for heating the stage 135. The film forming apparatus 100 further includes a carrier gas supply unit 111, and the carrier gas supply unit 111, the raw material container 120, and the film forming chamber 131 are connected by pipes 113 and 124. The carrier gas 151 and the film forming raw material mist 122 are mixed in the raw material container 120 to form a gas mixture 152, which is supplied to the film forming chamber 131.

[0062] The film-forming raw material solution 121 is not particularly limited as long as it can be misted, and a solution in which a metal is dissolved or dispersed in an organic solvent or water in the form of a complex or salt can be used. The metal is not limited as long as it can form a corundum structure as a metal oxide crystal, and examples of the metal include Al, Ti, V, Cr, Fe, Co, Ni, Ga, Rh, In, and Ir. Examples of the salt include halide salts such as metal chloride salts, metal bromide salts, and metal iodide salts. The metal can also be used as a salt solution in which the metal is dissolved in hydrogen halide such as hydrochloric acid, hydrobromic acid, and hydroiodic acid. Examples of the complex include an acetylacetone complex, a carbonyl complex, an ammine complex, and a hydride complex. An acetylacetonate complex can also be formed by mixing acetylacetone with the salt solution.

[0063] The metal content in the film-forming raw material solution is not particularly limited and can be appropriately set depending on the purpose. It is preferably 0.001 mol / L or more and 2 mol / L or less, and more preferably 0.01 mol / L or more and 0.7 mol / L or less.

[0064] The film-forming raw material solution may contain a dopant. The dopant is not particularly limited, and examples thereof include n-type dopants such as tin, silicon, germanium, titanium, zirconium, vanadium, and niobium, and p-type dopants such as copper, silver, cobalt, iridium, rhodium, magnesium, and nickel.

[0065] The atomization means for the film-forming raw solution 121 is not particularly limited as long as it can atomize or turn the film-forming raw solution 121 into droplets, and may be any known means, but in the present invention, an atomization means using ultrasonic waves is preferred. The mist or droplets obtained using ultrasonic waves are preferable because they have an initial velocity of zero and float in the air, and are not sprayed like a spray, but are mist that floats in space and can be transported as a gas, so they are very suitable because they are not damaged by collision energy. The droplet size is not particularly limited, and may be droplets of about several mm, but is preferably 50 μm or less, and more preferably 0.1 to 10 μm.

[0066] In addition, a plurality of source containers 120 may be provided depending on the material to be deposited. In this case, the gas mixture 152 supplied from the plurality of source containers 120 to the deposition chamber 131 may be supplied to the deposition chamber 131 independently, or may be mixed in the piping 124 or in a separate mixing container (not shown).

[0067] The source material container 120 may further include a temperature control means (not shown) for directly or indirectly adjusting the temperature of the film-forming source material solution 121. The temperature of the film-forming source material solution 121 is not particularly limited as long as it is a temperature at which atomization is possible, but is preferably 10°C to 90°C, and more preferably 20°C to 50°C. In this way, the temperature drop on the film-forming surface of the substrate 130 is mitigated, enabling better film formation. On the other hand, if the temperature exceeds 90°C, the vaporization of the film-forming source material mist 122 is promoted, which may reduce the yield in film formation or introduce defects into the film surface.

[0068] The carrier gas supply unit 111 supplies a carrier gas 151. The type of carrier gas 151 is not particularly limited, and in addition to an inert gas such as nitrogen or argon, air, oxygen, ozone, or a reducing gas such as hydrogen or forming gas can be used, or a mixture of a plurality of these gases can be used. The flow rate of the carrier gas can be appropriately set depending on the size of the substrate and the size of the film formation chamber, and can be, for example, about 0.01 to 100 L / min.

[0069] The carrier gas supply unit 111 may be an air compressor, various gas cylinders, a nitrogen gas separator, or the like, and may also be provided with a mechanism for controlling the supply flow rate of the gas.

[0070] The pipes 113 and 124 are not particularly limited as long as they are sufficiently stable against the film-forming raw material solution 121 and the temperatures inside and outside the film-forming chamber 131, and in addition to quartz, pipes made of common resins such as polyethylene, polypropylene, polyvinyl chloride, silicone resin, urethane resin, and fluororesin can be widely used.

[0071] Although not shown in the figure, a pipe that does not pass through the raw material container 120 may be connected to a separate pipe 124 from the carrier gas supply unit 111, and a dilution gas may be further added to the mixed gas 152 to adjust the ratio of the film forming raw material mist 122 and the carrier gas 151. The flow rate of the dilution gas may be appropriately set, and may be, for example, 0.1 to 10 times the flow rate of the carrier gas per minute. The dilution gas may be supplied, for example, downstream of the raw material container 120. The dilution gas may be the same as the carrier gas 151, or may be different.

[0072] A supply pipe 134 is installed in the film formation chamber 131, which is connected to the piping 124 and supplies the gas mixture 152 into the film formation chamber 131. The supply pipe 134 may be, for example, a tube made of quartz, glass, or resin. An exhaust port 133 for exhaust gas may be provided at a position that does not affect the supply of mist from the supply pipe 134.

[0073] The structure and material of the film formation chamber 131 are not particularly limited. For example, metals such as aluminum and stainless steel may be used, and when film formation is performed at higher temperatures, quartz, silicon carbide, or glass may be used.

[0074] A stage 135 is provided at the bottom of the film formation chamber 131, and the substrate 130 is placed on the stage 135. The stage 135 is equipped with a heating means 132, and the substrate 130 is heated by heating the stage 135. The heating temperature of the substrate 130 is appropriately adjusted depending on the film formation raw material mist 122 used and the film formation conditions, but can generally be in the range of 120°C to 600°C.

[0075] The material of the stage 135 may be appropriately selected according to the process conditions such as the raw material used in the film formation and the heating temperature. For example, stainless steel, Hastelloy, brass, copper, graphite, and ceramics such as silicon carbide, alumina, and aluminum nitride are preferably used. A known heating means can be applied to the heating means 132, and resistance heating, electromagnetic induction heating, or lamp heating is preferably used. In addition, in order to increase the thermal conduction to the substrate 130, the surface roughness Ra of the substrate mounting surface of the stage 135 is 0.5 μm or less. More preferably, the waviness Wa is 50 μm or less. The smaller the surface roughness Ra, the more preferable it is, and the lower limit is not particularly limited, but it can be, for example, 0.1 nm or more. If Ra exceeds 0.5 μm, the contact area with the substrate 130 decreases, thereby deteriorating the thermal conduction, and the temperature drop of the substrate surface during film formation by the mist of the film-forming raw material is significant, resulting in a decrease in the crystal orientation of the semiconductor film. The surface roughness Ra may be measured at one or more arbitrary points on the mounting surface, with a measurement length of, for example, 20 μm or more. The smaller the waviness Wa, the more preferable, and the lower limit is not particularly limited, but it can be, for example, 0.5 μm or more. If Wa is 50 μm or less, the contact area with the substrate 130 increases, improving thermal conduction, and the temperature drop of the substrate surface during film formation by the film-forming raw material mist is not significant, so that the crystal orientation of the semiconductor film does not decrease. The waviness Wa may be measured on one or more arbitrary straight lines on the mounting surface that are appropriately determined according to the shape of the mounting surface. For example, when the mounting surface is circular, the diameter of the circle can be the measurement length on two straight lines that intersect at right angles at the center of the circle. The surface roughness Ra and waviness Wa refer to values ​​calculated based on JIS B 0601 using the results of surface shape measurement using a stylus method, an atomic force microscope (AFM) method, or a non-contact measuring method using a laser microscope or a confocal microscope, such as an optical interference method, a confocal method, or an image synthesis method using focal movement.

[0076] The stage 135 may further include a substrate fixing mechanism (not shown). In this case, a known substrate fixing mechanism such as a vacuum chuck, an electrostatic chuck, or a mechanical clamp is preferably used, but a vacuum chuck is preferably used. In this case, the degree of vacuum should be 80 kPa or less in order to stably hold and heat the substrate. The lower the degree of vacuum, the better, but on the other hand, the larger the vacuum pump, so from the standpoint of cost, it can be 1 kPa or more.

[0077] (Laminate manufacturing equipment) The present invention also provides an apparatus for manufacturing a laminate including a semiconductor film having a corundum type crystal structure, comprising: a stage on which a substrate is placed; A heating means for heating the substrate; an atomizing means for atomizing a film-forming raw material solution; a gas mixture supplying means for mixing the atomized film-forming raw material solution with a carrier gas and supplying the mixture to the substrate, The surface of the stage that comes into contact with the substrate has a surface roughness Ra of 0.5 μm or less.

[0078] In the present invention, the waviness Wa of the contact surface of the stage with the substrate is preferably 50 μm or less. The smaller the waviness Wa, the more preferable it is. The lower limit is not particularly limited, but it can be, for example, 0.5 μm or more. If Wa is 50 μm or less, the contact area with the substrate 130 increases, improving thermal conduction, and the temperature drop of the substrate surface during film formation by the film-forming raw material mist is not significant, so that the crystal orientation of the semiconductor film does not deteriorate. The waviness Wa may be measured on one or more arbitrary straight lines on the mounting surface that are appropriately determined according to the shape of the mounting surface. For example, when the mounting surface is circular, the diameter of the circle on two straight lines that intersect at right angles at the center of the circle can be used as the measurement length.

[0079] (Method of manufacturing laminate) The present invention also provides a method for producing a laminate including a semiconductor film having a corundum type crystal structure, comprising the steps of: placing a substrate on a stage; heating the substrate; A step of atomizing a film-forming raw material solution; mixing the atomized film-forming raw material solution with a carrier gas to form a mixture; supplying the gas mixture to the substrate to form a film; Including, This is a method for manufacturing a laminate, in which the surface of the stage that comes into contact with the base and the surface of the base that comes into contact with the stage have a surface roughness Ra of 0.5 μm or less.

[0080] In the present invention, the substrate has a second main surface (also called the back surface) located opposite to the first main surface on which the semiconductor film is formed, and the surface roughness Ra of the second main surface is 0.5 μm or less. The second main surface is the surface of the substrate 130 that comes into contact with the mounting surface of the stage 135. If the surface roughness Ra of the second main surface exceeds 0.5 μm, the contact area with the substrate mounting surface of the stage 135 decreases, deteriorating the thermal conduction, and the temperature drop of the substrate surface during film formation due to the raw material mist becomes significant, resulting in a decrease in the crystal orientation of the semiconductor film. Here, the shape of the substrate 130 may be any shape having a first main surface and a second main surface located opposite to the first main surface, and may be, for example, a plate-like shape such as a flat plate or a disc, a rod-like shape, a cylindrical shape, a prismatic shape, a cylindrical shape, a ring-like shape, or the like, but is preferably a plate-like shape.

[0081] The substrate 130 is not particularly limited as long as it can support the semiconductor film to be formed. The material of the substrate 130 is also not particularly limited, and may be a known material, and may be an organic compound or an inorganic compound. Examples of the material include polysulfone, polyethersulfone, polyphenylene sulfide, polyetheretherketone, polyimide, polyetherimide, fluororesin, metals such as iron, aluminum, stainless steel, and gold, quartz, glass, calcium carbonate, gallium oxide, and ZnO. In particular, a single crystal substrate is preferable, and it is preferable to use a single crystal substrate of GaN, SiC, lithium tantalate, lithium niobate, silicon, sapphire, or α-type gallium oxide, since it is easier to obtain a laminate with good crystal orientation.

[0082] In addition, the area of ​​the semiconductor film formation surface is 5 cm 2 More than 10cm, preferably 10cm 2 A substrate having a thickness of 50 to 5000 μm or more, more preferably 100 to 2000 μm, can be suitably used. If the thickness is 50 μm or more, it is easy to support the semiconductor film, and if the thickness is 5000 μm or less, the temperature drop on the substrate surface due to the mist of the film-forming raw material is not significant, and the crystal orientation of the semiconductor film is not deteriorated.

[0083] In order to increase the thermal conduction to the substrate 130, the surface roughness Ra of the substrate mounting surface of the stage 135 is set to 0.5 μm or less. More preferably, the waviness Wa is set to 50 μm or less. The smaller the surface roughness Ra, the more preferable it is. The lower limit is not particularly limited, but it can be set to, for example, 0.1 nm or more. If the surface roughness Ra exceeds 0.5 μm, the contact area with the substrate 130 decreases, which deteriorates the thermal conduction, and the temperature drop of the substrate surface during film formation by the film-forming raw material mist becomes significant, which deteriorates the crystal orientation of the semiconductor film. The surface roughness Ra may be measured at one or more arbitrary points on the mounting surface, with a measurement length of, for example, 20 μm or more. The smaller the waviness Wa, the more preferable it is. The lower limit is not particularly limited, but it can be set to, for example, 0.5 μm or more. If Wa is 50 μm or less, the contact area with the substrate 130 is increased, and the heat conduction is improved, and the temperature drop of the substrate surface during film formation due to the mist of the film-forming raw material is not significant, and the crystal orientation of the semiconductor film is not reduced. The waviness Wa may be measured on one or more arbitrary straight lines on the mounting surface that are appropriately determined according to the shape of the mounting surface. For example, when the mounting surface is circular, the diameter of the circle on two straight lines that intersect at right angles at the center of the circle can be the measurement length. The surface roughness Ra and the waviness Wa refer to values ​​calculated based on JIS B 0601 using the results of surface shape measurement using a non-contact measurement method using a laser microscope or a confocal microscope, such as a stylus method, an atomic force microscope (AFM) method, or an optical interference method, a confocal method, or an image synthesis method using focal movement. Then, by combining such a stage with a substrate having a surface roughness Ra of 0.5 μm or less on the second main surface as described above, a high-quality laminate with excellent crystal orientation can be obtained even when a thick film is formed. In this case, the thickness of the semiconductor film is preferably 1 μm or more.

[0084] In the step of placing the substrate on the stage, the method of placing the substrate on the stage is not particularly limited, and a known method can be used. The stage 135 may further include a substrate fixing mechanism (not shown). In this case, a known substrate fixing mechanism such as a vacuum chuck, an electrostatic chuck, or a mechanical clamp is preferably used. However, it is preferable to use a vacuum chuck. In this case, the degree of vacuum is preferably 80 kPa or less in order to stably hold and heat the substrate. The lower the degree of vacuum, the better, but on the other hand, since the vacuum pump becomes large, it can be 1 kPa or more from the viewpoint of cost.

[0085] In the step of heating the substrate, the heating method is not particularly limited and any known method can be used, but it is particularly preferable to heat the stage. Also, the heating temperature is not particularly limited.

[0086] In the step of atomizing the film-forming raw material solution, the method of atomizing the film-forming raw material solution is not particularly limited, and a known method can be used, preferably a method using ultrasonic waves. The film-forming raw material solution is not particularly limited as long as it can be atomized, and a solution in which a metal is dissolved or dispersed in an organic solvent or water in the form of a complex or salt can be used.

[0087] In the step of mixing the atomized film-forming raw material solution with a carrier gas to form a gas mixture, the method of mixing the atomized film-forming raw material solution with a carrier gas to form a gas mixture is not particularly limited, and a known method can be used. The type of carrier gas is not particularly limited, and in addition to an inert gas such as nitrogen or argon, air, oxygen, ozone, or a reducing gas such as hydrogen or forming gas can be used, or a mixture of a plurality of these gases can be used.

[0088] In the step of supplying the gas mixture to the substrate to form a film, the method of supplying the gas mixture to the substrate and the method of forming a film are not particularly limited, and any known method can be used.

[0089] Such a method for producing a laminate can provide a method for producing a laminate capable of stably forming a thick semiconductor film having a high-quality corundum-type crystal structure with excellent crystal orientation.

[0090] (Laminate manufacturing system) The present invention also provides a system for manufacturing a laminate including a semiconductor film having a corundum type crystal structure, comprising: A mechanism for placing the substrate on the stage; A mechanism for heating the substrate; and A mechanism for atomizing a film-forming raw material solution; a mechanism for mixing the atomized film-forming raw material solution with a carrier gas to form a mixture; a mechanism for supplying the gas mixture to the substrate to form a film; Including, The system for manufacturing a laminate includes a surface roughness Ra of 0.5 μm or less on the contact surface of the stage with the base and on the contact surface of the base with the stage.

[0091] In the present invention, the substrate has a second main surface (also called the back surface) located opposite to the first main surface on which the semiconductor film is formed, and the surface roughness Ra of the second main surface is 0.5 μm or less. The second main surface is the surface of the substrate 130 that comes into contact with the mounting surface of the stage 135. If the surface roughness Ra of the second main surface exceeds 0.5 μm, the contact area with the substrate mounting surface of the stage 135 decreases, deteriorating the thermal conduction, and the temperature drop of the substrate surface during film formation due to the raw material mist becomes significant, resulting in a decrease in the crystal orientation of the semiconductor film. Here, the shape of the substrate 130 may be any shape having a first main surface and a second main surface located opposite to the first main surface, and may be, for example, a plate-like shape such as a flat plate or a disc, a rod-like shape, a cylindrical shape, a prismatic shape, a cylindrical shape, a ring-like shape, or the like, but is preferably a plate-like shape.

[0092] The substrate 130 is not particularly limited as long as it can support the semiconductor film to be formed. The material of the substrate 130 is also not particularly limited, and may be a known material, and may be an organic compound or an inorganic compound. Examples of the material include polysulfone, polyethersulfone, polyphenylene sulfide, polyetheretherketone, polyimide, polyetherimide, fluororesin, metals such as iron, aluminum, stainless steel, and gold, quartz, glass, calcium carbonate, gallium oxide, and ZnO. In particular, a single crystal substrate is preferable, and it is preferable to use a single crystal substrate of GaN, SiC, lithium tantalate, lithium niobate, silicon, sapphire, or α-type gallium oxide, since it is easier to obtain a laminate with good crystal orientation.

[0093] In addition, the area of ​​the semiconductor film formation surface is 5 cm 2 More than 10cm, preferably 10cm 2 A substrate having a thickness of 50 to 5000 μm or more, more preferably 100 to 2000 μm, can be suitably used. If the thickness is 50 μm or more, it is easy to support the semiconductor film, and if the thickness is 5000 μm or less, the temperature drop on the substrate surface due to the mist of the film-forming raw material is not significant, and the crystal orientation of the semiconductor film is not deteriorated.

[0094] In order to increase the thermal conduction to the substrate 130, the surface roughness Ra of the substrate mounting surface of the stage 135 is set to 0.5 μm or less. More preferably, the waviness Wa is set to 50 μm or less. The smaller the surface roughness Ra, the more preferable it is. The lower limit is not particularly limited, but it can be set to, for example, 0.1 nm or more. If the surface roughness Ra exceeds 0.5 μm, the contact area with the substrate 130 decreases, which deteriorates the thermal conduction, and the temperature drop of the substrate surface during film formation by the film-forming raw material mist becomes significant, which deteriorates the crystal orientation of the semiconductor film. The surface roughness Ra may be measured at one or more arbitrary points on the mounting surface, with a measurement length of, for example, 20 μm or more. The smaller the waviness Wa, the more preferable it is. The lower limit is not particularly limited, but it can be set to, for example, 0.5 μm or more. If Wa is 50 μm or less, the contact area with the substrate 130 is increased, and the heat conduction is improved, and the temperature drop of the substrate surface during film formation due to the mist of the film-forming raw material is not significant, and the crystal orientation of the semiconductor film is not reduced. The waviness Wa may be measured on one or more arbitrary straight lines on the mounting surface that are appropriately determined according to the shape of the mounting surface. For example, when the mounting surface is circular, the diameter of the circle on two straight lines that intersect at right angles at the center of the circle can be the measurement length. The surface roughness Ra and the waviness Wa refer to values ​​calculated based on JIS B 0601 using the results of surface shape measurement using a non-contact measurement method using a laser microscope or a confocal microscope, such as a stylus method, an atomic force microscope (AFM) method, or an optical interference method, a confocal method, or an image synthesis method using focal movement. Then, by combining such a stage with a substrate having a surface roughness Ra of 0.5 μm or less on the second main surface as described above, a high-quality laminate with excellent crystal orientation can be obtained even when a thick film is formed. In this case, the thickness of the semiconductor film is preferably 1 μm or more.

[0095] In the mechanism for mounting the substrate on the stage, the method for mounting the substrate on the stage is not particularly limited, and a known method can be used. The stage 135 may further include a substrate fixing mechanism (not shown). In this case, a known substrate fixing mechanism such as a vacuum chuck, an electrostatic chuck, or a mechanical clamp is preferably used. However, it is preferable to use a vacuum chuck. In this case, the degree of vacuum is preferably 80 kPa or less in order to stably hold and heat the substrate. The lower the degree of vacuum, the better, but on the other hand, since the vacuum pump becomes larger, it can be 1 kPa or more from the viewpoint of cost.

[0096] In the mechanism for heating the substrate, the heating method is not particularly limited and any known method can be used, but it is particularly preferable to heat the stage. Also, the heating temperature is not particularly limited.

[0097] In the mechanism for atomizing the film-forming raw material solution, the method of atomizing the film-forming raw material solution is not particularly limited, and a known method can be used, preferably a method using ultrasonic waves. The film-forming raw material solution is not particularly limited as long as it can be atomized, and a solution in which a metal is dissolved or dispersed in an organic solvent or water in the form of a complex or salt can be used.

[0098] In the mechanism for forming a gas mixture by mixing the atomized film-forming raw material solution with a carrier gas, the method for forming the gas mixture by mixing the atomized film-forming raw material solution with a carrier gas is not particularly limited, and a known method can be used. The type of carrier gas is not particularly limited, and in addition to an inert gas such as nitrogen or argon, air, oxygen, ozone, or a reducing gas such as hydrogen or forming gas can be used, or a mixture of a plurality of these gases can be used.

[0099] In the mechanism for supplying the gas mixture to the substrate to form a film, the method for supplying the gas mixture to the substrate and the method for forming a film are not particularly limited, and known methods can be used.

[0100] Such a method for producing a laminate can provide a method for producing a laminate capable of stably forming a thick semiconductor film having a high-quality corundum-type crystal structure with excellent crystal orientation. EXAMPLES

[0101] The present invention will be specifically described below using examples and comparative examples, but the present invention is not limited to these.

[0102] Example 1 Using the film formation apparatus shown in FIG. 1, a film of α-gallium oxide was formed. The atomization means for film formation was an atomization device equipped with a quartz raw material container and two ultrasonic vibrators (frequency 2.4 MHz). The film formation chamber was made of quartz, and was equipped with a quartz supply pipe and a silicon carbide hot plate as a stage. The surface roughness Ra of the substrate mounting surface of the stage was 0.05 μm, and the waviness Wa was 4.3 μm. A gas cylinder filled with nitrogen gas was used to supply the carrier gas. The gas cylinder and the atomization device for film formation were connected with a urethane resin tube, and the atomization device for film formation and the supply pipe were further connected with quartz piping. Next, gallium acetylacetonate was mixed at a ratio of 0.1 mol / L into a solution in which 34% hydrochloric acid was added to pure water at a volume ratio of 1%, and the mixture was dissolved by stirring with a stirrer for 60 minutes to prepare a raw material solution for film formation. Next, the raw material solution for film formation was filled into a raw material container, and ultrasonic vibration was propagated to the raw material solution for film formation in the raw material container through ultrasonic propagation water by an ultrasonic vibrator, so that the raw material solution for film formation was atomized (misted). At this time, the temperature of the ultrasonic propagation water was adjusted, and the raw material solution for film formation was kept at 35°C. Next, a c-plane sapphire substrate (base) with a diameter of 10 cm (4 inches), a thickness of 0.6 mm, a back surface roughness Ra of 0.05 μm, and a waviness Wa of 1.9 μm was placed on the mounting surface of the stage and fixed in place by reducing the pressure to 20 kPa with a vacuum pump. After this, the stage was heated so that the temperature of the stage surface reached 500°C. Next, nitrogen gas was added to the source container at a flow rate of 5 L / min, and the mixture of mist and nitrogen gas was supplied to the deposition chamber for 30 minutes to form a film. Immediately after this, the supply of nitrogen gas was stopped, and the supply of the mixture to the deposition chamber was stopped. The crystal layer of the fabricated laminate was confirmed to be α-Ga2O3 by X-ray diffraction measurement. The half-width was then evaluated by measuring the rocking curve of X-ray diffraction, and the thickness of the crystal layer was measured by ellipsometry.

[0103] Example 2 Film formation was carried out in the same manner as in Example 1, except that the surface roughness Ra of the substrate mounting surface of the stage was set to 0.45 μm and the surface roughness Ra of the substrate back surface was set to 0.41 μm. The crystal layer of the fabricated laminate was confirmed to be α-Ga2O3 by X-ray diffraction measurement. Thereafter, the half-value width and thickness of the crystal layer were evaluated in the same manner as in Example 1.

[0104] Example 3 Film formation was carried out in the same manner as in Example 2, except that the time for supplying the gas mixture to the film formation chamber was 150 minutes. The crystal layer of the fabricated laminate was confirmed to be α-Ga2O3 by X-ray diffraction measurement. Thereafter, the half-value width and thickness of the crystal layer were evaluated in the same manner as in Example 1.

[0105] Example 4 Film formation was carried out in the same manner as in Example 1, except that the degree of vacuum for fixing the substrate was 75 kPa. The crystal layer of the fabricated laminate was confirmed to be α-Ga2O3 by X-ray diffraction measurement. Thereafter, the half-value width and thickness of the crystal layer were evaluated in the same manner as in Example 1.

[0106] Comparative Example 1 Film formation was carried out in the same manner as in Example 1, except that the surface roughness Ra of the substrate mounting surface of the stage was set to 0.60 μm. The crystal layer of the fabricated laminate was confirmed to be α-Ga2O3 by X-ray diffraction measurement. Thereafter, the half-value width and thickness of the crystal layer were evaluated in the same manner as in Example 1.

[0107] Comparative Example 2 Film formation was carried out in the same manner as in Example 1, except that the surface roughness Ra of the back surface of the substrate was set to 0.62 μm. The crystal layer of the fabricated laminate was confirmed to be α-Ga2O3 by X-ray diffraction measurement. Thereafter, the half-value width and thickness of the crystal layer were evaluated in the same manner as in Example 1.

[0108] Comparative Example 3 Film formation was carried out in the same manner as in Example 1, except that the surface roughness Ra of the back surface of the substrate was set to 0.62 μm, and the time for supplying the gas mixture to the film formation chamber was set to 150 minutes. The crystal layer of the fabricated laminate was confirmed to be α-Ga2O3 by X-ray diffraction measurement. Thereafter, the half-value width and thickness of the crystal layer were evaluated in the same manner as in Example 1.

[0109] Comparative Example 4 Film formation was carried out in the same manner as in Example 1, except that the surface roughness Ra of the back surface of the substrate was set to 0.62 μm, and the degree of vacuum for fixing the substrate was set to 95 kPa. The crystal layer of the fabricated laminate was confirmed to be α-Ga2O3 by X-ray diffraction measurement. Thereafter, the half-value width and thickness of the crystal layer were evaluated in the same manner as in Example 1.

[0110] Example 5 Film formation was carried out in the same manner as in Example 1, except that the waviness Wa of the back surface of the substrate was set to 45.8 μm. The crystal layer of the fabricated laminate was confirmed to be α-Ga2O3 by X-ray diffraction measurement. Thereafter, the half-value width and thickness of the crystal layer were evaluated in the same manner as in Example 1.

[0111] Example 6 Film formation was carried out in the same manner as in Example 1, except that the waviness Wa of the stage mounting surface was set to 48.2 μm. The crystal layer of the fabricated laminate was confirmed to be α-Ga2O3 by X-ray diffraction measurement. Thereafter, the half-value width and thickness of the crystal layer were evaluated in the same manner as in Example 1.

[0112] Example 7 Film formation was carried out in the same manner as in Example 1, except that the waviness Wa of the back surface of the substrate was set to 47.7 μm, and the waviness Wa of the stage mounting surface was set to 48.2 μm. The crystal layer of the fabricated laminate was confirmed to be α-Ga2O3 by X-ray diffraction measurement. Thereafter, the half-value width and thickness of the crystal layer were evaluated in the same manner as in Example 1.

[0113] Example 8 Film formation was carried out in the same manner as in Example 1, except that the waviness Wa of the stage mounting surface was set to 59.7 μm. The crystal layer of the fabricated laminate was confirmed to be α-Ga2O3 by X-ray diffraction measurement. Thereafter, the half-value width and thickness of the crystal layer were evaluated in the same manner as in Example 1.

[0114] Example 9 Film formation was carried out in the same manner as in Example 1, except that the waviness Wa of the back surface of the substrate was set to 52.1 μm. The crystal layer of the fabricated laminate was confirmed to be α-Ga2O3 by X-ray diffraction measurement. Thereafter, the half-value width and thickness of the crystal layer were evaluated in the same manner as in Example 1.

[0115] Table 1 shows the film thicknesses and half-widths of the rocking curves of the crystal layers obtained in Examples 1 to 9 and Comparative Examples 1 to 4. [Table 1]

[0116] From Table 1, as shown in Examples 1 to 9, it can be seen that the film forming apparatus according to the laminate manufacturing method of the present invention is an excellent device capable of producing a high-quality crystal layer (semiconductor film) that combines a film thickness of more than 1 μm with a low half-width (high crystal orientation). On the other hand, in Comparative Examples 1 to 4, in which the surface roughness Ra of either the stage mounting surface or the back surface of the substrate exceeded 0.5 μm, the half-width increased and the growth rate tended to increase (decreased crystal orientation). This is thought to be the result of abnormal film growth caused by a drop in temperature on the film surface.

[0117] The present invention is not limited to the above-described embodiment. The above-described embodiment is merely an example, and anything that has substantially the same configuration as the technical idea described in the claims of the present invention and exhibits similar effects is included in the technical scope of the present invention.

Claims

1. A method for producing a laminate including a semiconductor film having a corundum type crystal structure, comprising the steps of: placing a substrate on a stage; heating the substrate; A step of atomizing a film-forming raw material solution; mixing the atomized film-forming raw material solution with a carrier gas to form a mixture; supplying the gas mixture to the substrate to form a film; Including, A method for manufacturing a laminate, comprising the steps of: setting a surface roughness Ra of a contact surface of said stage with said base body and a contact surface of said base with said stage to 0.5 μm or less.

2. 2. The method for manufacturing a laminate according to claim 1, wherein a waviness Wa of a contact surface of the stage with the base and a contact surface of the base with the stage are set to 50 [mu]m or less.

3. 3. The method for manufacturing a laminate according to claim 1, wherein the stage is heated in the step of heating the base.

4. 4. The method for producing a laminate according to claim 1, wherein the substrate has a thickness of 50 μm or more and 5000 μm or less.

5. 5. The method for producing a laminate according to claim 1, wherein the substrate is a single crystal.

6. 6. The method for manufacturing a laminate according to claim 1, wherein the step of placing the substrate on a stage further includes a step of vacuum fixing the substrate to the stage, and the degree of vacuum is 80 kPa or less.

7. An apparatus for manufacturing a laminate including a semiconductor film having a corundum type crystal structure, a stage on which a substrate is placed; A heating means for heating the substrate; an atomizing means for atomizing a film-forming raw material solution; a gas mixture supplying means for mixing the atomized film-forming raw material solution with a carrier gas and supplying the mixture to the substrate, 11. The laminate manufacturing apparatus according to claim 10, wherein the surface roughness Ra of the surface of said stage that comes into contact with said substrate is 0.5 μm or less, and said stage is equipped with a vacuum chuck.

8. 8. The laminate manufacturing apparatus according to claim 7, wherein a waviness Wa of the contact surface of the stage with the base is 50 [mu]m or less.

9. A laminate comprising: A laminate comprising a substrate, and a semiconductor film having a corundum-type crystal structure on a first main surface of the substrate directly or via another layer, the second main surface being the opposite surface to the first main surface of the substrate, the surface roughness Ra of the second main surface being 0.5 μm or less, and the half-width as measured by X-ray diffraction rocking curve measurement being 32.4 seconds or less.

10. 10. The laminate according to claim 9, wherein the thickness of the substrate is 50 μm or more and 5000 μm or less.

11. 11. The laminate according to claim 9, wherein the substrate is a single crystal.

12. 12. The laminate according to claim 9, wherein the semiconductor film has a thickness of 1 μm or more.

13. A semiconductor device comprising at least a semiconductor layer and an electrode, the semiconductor layer comprising at least a part of the laminate according to any one of claims 9 to 12.

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