WO2022030650A1 - Élément à semi-conducteur et dispositif à semi-conducteur - Google Patents

Élément à semi-conducteur et dispositif à semi-conducteur Download PDF

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WO2022030650A1
WO2022030650A1 PCT/JP2021/029577 JP2021029577W WO2022030650A1 WO 2022030650 A1 WO2022030650 A1 WO 2022030650A1 JP 2021029577 W JP2021029577 W JP 2021029577W WO 2022030650 A1 WO2022030650 A1 WO 2022030650A1
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layer
semiconductor
metal
substrate
semiconductor layer
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Japanese (ja)
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秀彰 ▲柳▼田
尚吾 水本
裕之 安藤
佑典 松原
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株式会社Flosfia
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    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
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    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
    • H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
    • H01L21/20—Deposition of semiconductor materials on a substrate, e.g. epitaxial growth solid phase epitaxy
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    • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
    • H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
    • H01L21/28—Manufacture of electrodes on semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/268
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    • H01L29/02—Semiconductor bodies ; Multistep manufacturing processes therefor
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    • H01L29/02—Semiconductor bodies ; Multistep manufacturing processes therefor
    • H01L29/12—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by the materials of which they are formed
    • H01L29/24—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by the materials of which they are formed including, apart from doping materials or other impurities, only semiconductor materials not provided for in groups H01L29/16, H01L29/18, H01L29/20, H01L29/22
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    • H01L29/40—Electrodes ; Multistep manufacturing processes therefor
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    • H01L29/66—Types of semiconductor device ; Multistep manufacturing processes therefor
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    • H01L29/66075—Multistep manufacturing processes of devices having semiconductor bodies comprising group 14 or group 13/15 materials
    • H01L29/66227—Multistep manufacturing processes of devices having semiconductor bodies comprising group 14 or group 13/15 materials the devices being controllable only by the electric current supplied or the electric potential applied, to an electrode which does not carry the current to be rectified, amplified or switched, e.g. three-terminal devices
    • H01L29/66409—Unipolar field-effect transistors
    • H01L29/66848—Unipolar field-effect transistors with a Schottky gate, i.e. MESFET
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    • H01L29/66—Types of semiconductor device ; Multistep manufacturing processes therefor
    • H01L29/66007—Multistep manufacturing processes
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    • H01L29/66409—Unipolar field-effect transistors
    • H01L29/66893—Unipolar field-effect transistors with a PN junction gate, i.e. JFET
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    • H01L29/66—Types of semiconductor device ; Multistep manufacturing processes therefor
    • H01L29/68—Types of semiconductor device ; Multistep manufacturing processes therefor controllable by only the electric current supplied, or only the electric potential applied, to an electrode which does not carry the current to be rectified, amplified or switched
    • H01L29/76—Unipolar devices, e.g. field effect transistors
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    • H01L29/66—Types of semiconductor device ; Multistep manufacturing processes therefor
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    • H01L29/76—Unipolar devices, e.g. field effect transistors
    • H01L29/772—Field effect transistors
    • H01L29/80—Field effect transistors with field effect produced by a PN or other rectifying junction gate, i.e. potential-jump barrier
    • H01L29/808—Field effect transistors with field effect produced by a PN or other rectifying junction gate, i.e. potential-jump barrier with a PN junction gate, e.g. PN homojunction gate
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    • H01L29/66—Types of semiconductor device ; Multistep manufacturing processes therefor
    • H01L29/68—Types of semiconductor device ; Multistep manufacturing processes therefor controllable by only the electric current supplied, or only the electric potential applied, to an electrode which does not carry the current to be rectified, amplified or switched
    • H01L29/76—Unipolar devices, e.g. field effect transistors
    • H01L29/772—Field effect transistors
    • H01L29/80—Field effect transistors with field effect produced by a PN or other rectifying junction gate, i.e. potential-jump barrier
    • H01L29/812—Field effect transistors with field effect produced by a PN or other rectifying junction gate, i.e. potential-jump barrier with a Schottky gate
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    • H01L29/66—Types of semiconductor device ; Multistep manufacturing processes therefor
    • H01L29/86—Types of semiconductor device ; Multistep manufacturing processes therefor controllable only by variation of the electric current supplied, or only the electric potential applied, to one or more of the electrodes carrying the current to be rectified, amplified, oscillated or switched
    • H01L29/861—Diodes
    • H01L29/872—Schottky diodes

Definitions

  • the present invention relates to a semiconductor element useful as a power device or the like.
  • gallium oxide Ga 2 O 3
  • the gallium oxide can control the bandgap by forming a mixed crystal of indium and aluminum, respectively, or in combination, and constitutes an extremely attractive material system as an InAlGaO-based semiconductor. ..
  • a ⁇ gallium oxide substrate and a sapphire substrate have been studied.
  • Patent Document 2 when a ⁇ -gallium oxide substrate is used, homoepitaxial growth of gallium oxide is possible, and the quality of the aluminum gallium oxide thin film can be improved.
  • the size of the substrate that can be procured is limited, and it is difficult to increase the diameter as compared with materials such as silicon and sapphire that are already mass-produced.
  • sapphire is an insulator, there is a problem that an electric current cannot flow through the base material. In this case, the electrode cannot be formed on the base material, and the output current per unit area of the semiconductor device is limited.
  • the diameter is increased to 6 inches or 8 inches, the industrial application of these large diameter sapphires is not so advanced, so there is a concern about stable procurement and there is also a problem that the procurement cost rises.
  • the low thermal conductivity of gallium oxide and sapphire is also a problem of heat generation and high temperature operation due to the increase in current of semiconductor devices.
  • the characteristics of the base material also cause a problem in electrical characteristics for realizing a low-loss semiconductor device. For example, in order to realize a semiconductor having high withstand voltage and low loss, it is necessary to reduce the loss in the channel layer and also the loss in the non-channel layer. For example, it is required to reduce the loss in the contact region constituting the semiconductor device, and further, in the vertical semiconductor device, it is required to reduce the loss of the base material and the layer between the base material and the channel layer. ..
  • Patent Document 5 describes a laminated semiconductor structure in which a support layer containing a conductive material having a coefficient of thermal expansion different from that of the semiconductor layer is laminated on a semiconductor layer using an InAlGaO-based semiconductor via a conductive adhesive layer. Is described.
  • the semiconductor structure described in Cited Document 5 is not practically sufficient in terms of forward characteristics and the like, and is not sufficiently satisfactory in terms of warpage, which is a problem peculiar to InAlGaO-based semiconductors. Therefore, a semiconductor structure having excellent heat dissipation and electrical characteristics, which can sufficiently express the semiconductor characteristics of the InAlGaO-based semiconductor, has been desired.
  • Patent Document 1 and Patent Document 5 relate to a patent application by the present applicant.
  • An object of the present invention is to provide a semiconductor device having excellent electrical characteristics such as forward characteristics.
  • the present inventors use a conductive substrate containing molybdenum in the production (preliminary step) of a semiconductor element using a semiconductor layer containing a crystalline oxide semiconductor as a main component. It was found that not only the adhesion to the electrodes and the adhesive layer of the obtained semiconductor element is further improved, but also the warpage is suppressed and the electrical characteristics such as the forward characteristics of the obtained semiconductor element are improved. As a result of further studies, a semiconductor layer containing a crystalline oxide semiconductor as a main component, an electrode layer laminated on the semiconductor layer, and directly or via another layer on the electrode layer.
  • the semiconductor device according to the above [1] or [2], wherein the conductive substrate further contains a metal of Group 11 of the Periodic Table.
  • the conductive substrate has a laminated structure in which at least one layer containing a metal of Group 6 of the periodic table and a layer containing a metal of Group 11 of the periodic table are laminated one by one.
  • the semiconductor element described in. [6] The semiconductor device according to any one of the above [1] to [5], wherein the weight ratio of the Group 6 metal in the periodic table in the conductive substrate is 0.09 or more.
  • the semiconductor device of the present invention is excellent in electrical characteristics such as forward characteristics.
  • SIT static induction transistor
  • SBD Schottky barrier diode
  • PWM metal oxide film semiconductor field effect transistor
  • JFET junction field effect transistor
  • the semiconductor device of the present invention is laminated on a semiconductor layer containing a crystalline oxide semiconductor as a main component, an electrode layer laminated on the semiconductor layer, and directly or via another layer on the electrode layer. It is a semiconductor element including at least the conductive substrate, wherein the conductive substrate contains molybdenum.
  • the semiconductor layer is laminated on the base substrate directly or via another layer, and (2) the electrode layer is formed on the semiconductor layer.
  • the semiconductor element is formed by a manufacturing method including laminating the conductive substrate on the electrode layer via a conductive adhesive layer, if desired, and removing the base substrate by using a known means. It can be suitably manufactured.
  • the main steps (1) to (3) for manufacturing the semiconductor element will be described in more detail with reference to the drawings.
  • the semiconductor layer is laminated on the base substrate directly or via another layer.
  • a laminated body as shown in FIG. 1 can be obtained.
  • a crystalline semiconductor 101 is laminated on a base substrate 108.
  • the crystalline semiconductor film 101 obtained in the step (1) can be used as the semiconductor layer (hereinafter, also referred to as “semiconductor film”).
  • semiconductor film also referred to as “semiconductor film”.
  • the base substrate is not particularly limited as long as it has a plate shape and serves as a support for the semiconductor film. It may be an insulator substrate, a semiconductor substrate, a metal substrate or a conductive substrate, but it is preferable that the base substrate is an insulator substrate, and the surface thereof is formed. A substrate having a metal film is also preferable.
  • the base substrate includes, for example, a base substrate containing a substrate material having a corundum structure as a main component, a substrate substrate containing a substrate material having a ⁇ -galia structure as a main component, or a substrate material having a hexagonal structure as a main component. Examples include a base substrate including.
  • the "main component” means that the substrate material having the specific crystal structure has an atomic ratio of preferably 50% or more, more preferably 70% or more, still more preferably 90, based on all the components of the substrate material. It means that it is contained in% or more, and may be 100%.
  • the substrate material is not particularly limited and may be known as long as it does not interfere with the object of the present invention.
  • the substrate material having the above-mentioned corundum structure for example, ⁇ -Al 2 O 3 (sapphire substrate) or ⁇ -Ga 2 O 3 is preferably mentioned, and a-plane sapphire substrate, m-plane sapphire substrate, and r-plane sapphire substrate are preferable.
  • C-plane sapphire substrate, ⁇ -type gallium oxide substrate (a-plane, m-plane or r-plane) and the like are more preferable examples.
  • the base substrate containing the substrate material having a ⁇ -Galia structure as a main component for example, ⁇ -Ga 2 O 3 substrate or Ga 2 O 3 and Al 2 O 3 are included, and Al 2 O 3 is more than 0 wt%.
  • Examples thereof include a mixed crystal substrate having a content of 60 wt% or less.
  • Examples of the base substrate containing a substrate material having a hexagonal structure as a main component include a SiC substrate, a ZnO substrate, and a GaN substrate.
  • the semiconductor layer is not particularly limited as long as it contains a crystalline oxide semiconductor as a main component.
  • the crystal structure of the crystalline oxide semiconductor is also not particularly limited as long as the object of the present invention is not impaired.
  • the crystal structure of the crystalline oxide semiconductor includes, for example, a corundum structure, a ⁇ -galia structure, a hexagonal structure (for example, ⁇ -type structure, etc.), a rectangular structure (for example, ⁇ -type structure, etc.), a cubic structure, or a cubic structure. A square crystal structure and the like can be mentioned.
  • the crystalline oxide semiconductor preferably has a corundum structure, a ⁇ -Galia structure or a hexagonal structure (for example, a ⁇ -type structure), and more preferably has a corundum structure.
  • the crystalline oxide semiconductor include metal oxides containing one or more metals selected from aluminum, gallium, indium, iron, chromium, vanadium, titanium, rhodium, nickel, cobalt and iridium. can give.
  • the oxide semiconductor preferably contains at least one metal selected from aluminum, indium and gallium, more preferably at least gallium, ⁇ -Ga 2 O 3 Or the mixed crystal thereof is most preferable.
  • the "main component” means that the oxide semiconductor having the corundum structure is preferably 50% or more, more preferably 70% or more, still more preferably 70% or more, in terms of atomic ratio, with respect to all the components of the semiconductor layer. It means that it is contained in 90% or more, and it means that it may be 100%.
  • the thickness of the semiconductor layer is not particularly limited and may be 1 ⁇ m or less or 1 ⁇ m or more, but in the embodiment of the present invention, it is preferably 1 ⁇ m or more.
  • the surface area of the semiconductor layer is not particularly limited, and may be 1 mm 2 or more or 1 mm 2 or less, but is preferably 10 mm 2 to 300 cm 2 , preferably 100 mm 2 to 100 cm 2 . Is more preferable.
  • the semiconductor layer is usually a single crystal, but may be a polycrystal.
  • the semiconductor layer is a multilayer film including at least a first semiconductor layer and a second semiconductor layer, and when a Schottky electrode is provided on the first semiconductor layer, the first semiconductor layer. It is also preferable that the carrier density is smaller than that of the carrier density of the second semiconductor layer.
  • the second semiconductor layer usually contains a dopant, and the carrier density of the semiconductor layer can be appropriately set by adjusting the doping amount.
  • the semiconductor layer preferably contains a dopant.
  • the dopant is not particularly limited and may be a known one.
  • Examples of the dopant include n-type dopants such as tin, germanium, silicon, titanium, zirconium, vanadium and niobium, and p-type dopants such as magnesium, calcium and zinc.
  • the n-type dopant is preferably Sn, Ge or Si.
  • the content of the dopant is preferably 0.00001 atomic% or more, more preferably 0.00001 atomic% to 20 atomic%, and 0.00001 atomic% to 10 atomic% in the composition of the semiconductor layer. Is most preferable.
  • the concentration of the dopant may usually be about 1 ⁇ 10 16 / cm 3 to 1 ⁇ 10 22 / cm 3 , and the concentration of the dopant may be, for example, about 1 ⁇ 10 17 / cm.
  • the concentration may be as low as 3 or less.
  • the dopant may be contained in a high concentration of about 1 ⁇ 10 20 / cm 3 or more. In the embodiment of the present invention, it is preferably contained at a carrier concentration of 1 ⁇ 10 17 / cm 3 or more.
  • the semiconductor layer may be formed by using known means.
  • the means for forming the semiconductor layer include a CVD method, a MOCVD method, a MOVPE method, a mist CVD method, a mist epitaxy method, an MBE method, an HVPE method, a pulse growth method, and an ALD method.
  • the semiconductor layer forming means is a mist CVD method or a mist epitaxy method.
  • the raw material solution is atomized (atomization step) using the mist CVD apparatus shown in FIG. 12, droplets are suspended, and atomization obtained after atomization is performed.
  • a semiconductor film containing a crystalline oxide semiconductor as a main component on the substrate by transporting the droplets to the substrate with a carrier gas (transportation step) and then thermally reacting the atomized droplets in the film forming chamber.
  • the semiconductor layer is formed by laminating (depositioning step).
  • the atomization step atomizes the raw material solution.
  • the means for atomizing the raw material solution is not particularly limited as long as the raw material solution can be atomized, and may be known means, but in the embodiment of the present invention, the atomizing means using ultrasonic waves is preferable. ..
  • Atomized droplets obtained using ultrasonic waves have a zero initial velocity and are preferable because they float in the air. For example, instead of spraying them like a spray, they float in space and are transported as gas. Since it is a possible mist, it is not damaged by collision energy, so it is very suitable.
  • the droplet size is not particularly limited and may be a droplet of about several mm, but is preferably 50 ⁇ m or less, and more preferably 100 nm to 10 ⁇ m.
  • the raw material solution is not particularly limited as long as it can be atomized or atomized and contains a raw material capable of forming a semiconductor film, and may be an inorganic material or an organic material.
  • the raw material is preferably a metal or a metal compound, and is selected from aluminum, gallium, indium, iron, chromium, vanadium, titanium, rhodium, nickel, cobalt and iridium. It is more preferable to contain more than a kind of metal.
  • a solution in which the metal is dissolved or dispersed in an organic solvent or water in the form of a complex or a salt can be preferably used.
  • the form of the complex include an acetylacetonate complex, a carbonyl complex, an ammine complex, and a hydride complex.
  • the salt form include organic metal salts (for example, metal acetate, metal oxalate, metal citrate, etc.), metal sulfide salts, nitrified metal salts, phosphorylated metal salts, and halogenated metal salts (for example, metal chloride). Salts, metal bromide salts, metal iodide salts, etc.) and the like.
  • an additive such as a hydrohalic acid or an oxidizing agent with the raw material solution.
  • the hydrohalogen acid include hydrobromic acid, hydrochloric acid, hydroiodic acid, and the like. Among them, hydrobromic acid or hydrobromic acid because it can suppress the generation of abnormal grains more efficiently. Hydroiodic acid is preferred.
  • the oxidizing agent include hydrogen peroxide (H 2 O 2 ), sodium peroxide (Na 2 O 2 ), barium peroxide (BaO 2 ), benzoyl peroxide (C 6 H 5 CO) 2 O 2 and the like. Peroxides, hypochlorous acid (HClO), perchloric acid, nitric acid, ozone water, organic peroxides such as peracetic acid and nitrobenzene can be mentioned.
  • the raw material solution may contain a dopant.
  • the dopant By including the dopant in the raw material solution, doping can be performed satisfactorily.
  • the dopant is not particularly limited as long as it does not interfere with the object of the present invention.
  • the dopant include n-type dopants such as tin, germanium, silicon, titanium, zirconium, vanadium or niobium, or Mg, H, Li, Na, K, Rb, Cs, Fr, Be, Ca, Sr and Ba. , Ra, Mn, Fe, Co, Ni, Pd, Cu, Ag, Au, Zn, Cd, Hg, Ti, Pb, N, P-type dopants and the like.
  • the content of the dopant is appropriately set by using a calibration curve showing the relationship between the desired carrier density and the concentration of the dopant in the raw material.
  • the solvent of the raw material solution is not particularly limited, and may be an inorganic solvent such as water, an organic solvent such as alcohol, or a mixed solvent of an inorganic solvent and an organic solvent.
  • the solvent preferably contains water, and more preferably water or a mixed solvent of water and alcohol.
  • the atomized droplets are transported to the film forming chamber by the carrier gas.
  • the carrier gas is not particularly limited as long as the object of the present invention is not impaired, and for example, an inert gas such as oxygen, ozone, nitrogen or argon, or a reducing gas such as hydrogen gas or forming gas is a suitable example. Can be mentioned.
  • the type of the carrier gas may be one type, but may be two or more types, and a diluted gas having a reduced flow rate (for example, a 10-fold diluted gas) or the like is further used as the second carrier gas. May be good.
  • the carrier gas may be supplied not only at one place but also at two or more places.
  • the flow rate of the carrier gas is not particularly limited, but is preferably 0.01 to 20 L / min, and more preferably 1 to 10 L / min.
  • the flow rate of the diluted gas is preferably 0.001 to 2 L / min, more preferably 0.1 to 1 L / min.
  • the semiconductor film is formed on the substrate by thermally reacting the atomized droplets in the film forming chamber.
  • the thermal reaction may be any effect as long as the atomized droplets react with heat, and the reaction conditions and the like are not particularly limited as long as the object of the present invention is not impaired.
  • the thermal reaction is usually carried out at a temperature equal to or higher than the evaporation temperature of the solvent, but is preferably not too high (for example, 1000 ° C.) or lower, more preferably 650 ° C. or lower, and most preferably 300 ° C. to 650 ° C. preferable.
  • the thermal reaction is carried out under any of a vacuum, a non-oxygen atmosphere (for example, an inert gas atmosphere, etc.), a reducing gas atmosphere, and an oxygen atmosphere, as long as the object of the present invention is not impaired.
  • a vacuum for example, an inert gas atmosphere, etc.
  • a reducing gas atmosphere for example, a reducing gas atmosphere
  • an oxygen atmosphere for example, a nitrogen atmosphere
  • it is preferably carried out in an inert gas atmosphere or an oxygen atmosphere.
  • it may be carried out under any conditions of atmospheric pressure, pressurization and depressurization, but in the embodiment of the present invention, it is preferably carried out under atmospheric pressure.
  • the film thickness can be set by adjusting the film formation time.
  • an annealing treatment may be performed after the film forming step.
  • the annealing treatment temperature is not particularly limited as long as it does not impair the object of the present invention, and is usually 300 ° C. to 650 ° C., preferably 350 ° C. to 550 ° C.
  • the annealing treatment time is usually 1 minute to 48 hours, preferably 10 minutes to 24 hours, and more preferably 30 minutes to 12 hours.
  • the annealing treatment may be performed in any atmosphere as long as the object of the present invention is not impaired. It may be in a non-oxygen atmosphere or in an oxygen atmosphere.
  • non-oxygen atmosphere examples include an inert gas atmosphere (for example, a nitrogen atmosphere) and a reduced gas atmosphere, but in the embodiment of the present invention, the inert gas atmosphere is preferable, and the nitrogen atmosphere is preferable. It is more preferably below.
  • the semiconductor film may be provided directly on the base substrate, or other layers such as a stress relaxation layer (for example, a buffer layer, an ELO layer, etc.), a peeling sacrificial layer, and the like.
  • the semiconductor film may be provided via the above.
  • the means for forming each layer is not particularly limited and may be known means, but in the embodiment of the present invention, the mist CVD method is preferable.
  • the electrode layer 105b is formed on the semiconductor layer 101.
  • a laminated body as shown in FIG. 2 can be obtained.
  • the laminate of FIG. 2 is composed of a base substrate 108, a semiconductor layer 101, and an electrode layer 105b.
  • the electrode layer is not particularly limited as long as it has conductivity, as long as it does not impair the object of the present invention.
  • the constituent material of the electrode layer may be a conductive inorganic material or a conductive organic material.
  • the material of the electrode is preferably metal.
  • Preferred examples of the metal include at least one metal selected from Groups 4 to 10 of the Periodic Table. Examples of the metal of Group 4 of the periodic table include titanium (Ti), zirconium (Zr), and hafnium (Hf). Examples of the metal of Group 5 of the periodic table include vanadium (V), niobium (Nb), and tantalum (Ta).
  • Examples of the metal of Group 6 of the periodic table include chromium (Cr), molybdenum (Mo) and tungsten (W).
  • Examples of the metal of Group 7 of the periodic table include manganese (Mn), technetium (Tc), and rhenium (Re).
  • Examples of the metal of Group 8 of the periodic table include iron (Fe), ruthenium (Ru), and osmium (Os).
  • Examples of the metal of Group 9 of the Periodic Table include cobalt (Co), rhodium (Rh), and iridium (Ir).
  • Examples of the metal of Group 10 of the periodic table include nickel (Ni), palladium (Pd), platinum (Pt) and the like.
  • the electrode layer contains at least one metal selected from the Group 4 and Group 9 of the Periodic Table, and more preferably the metal of Group 9 of the Periodic Table. preferable.
  • the thickness of the electrode layer is not particularly limited, but is preferably 0.1 nm to 10 ⁇ m, more preferably 5 nm to 500 nm, and most preferably 10 nm to 200 nm. Further, in the embodiment of the present invention, the electrode layer may be composed of two or more layers having different compositions from each other.
  • the means for forming the electrode layer is not particularly limited, and may be a known means.
  • Specific examples of the means for forming the electrode layer or the other electrode layer include a dry method and a wet method.
  • Examples of the dry method include sputtering, vacuum deposition, and CVD.
  • Examples of the wet method include screen printing and die coating.
  • the conductive substrate is laminated on the electrode layer via a conductive adhesive layer, if desired, and the base substrate is removed by using a known means.
  • a laminated body as shown in FIG. 3 can be obtained.
  • the electrode layer 105b is bonded to the conductive substrate 107 via the conductive adhesive layer 106, and the semiconductor layer 101 is laminated on the electrode layer 105b.
  • the method for removing the base substrate include a method of removing by applying a mechanical impact, a method of removing by applying heat and utilizing thermal stress, a method of removing by applying vibration such as ultrasonic waves, and etching.
  • a method of removing by grinding, a method of removing by grinding, a method of removing by performing ion implantation such as a smart cut method and then performing a heat treatment, a method of removing by a laser lift-off method, a method of combining these, and the like can be mentioned. ..
  • the conductive adhesive layer is not particularly limited as long as it can join the electrode layer and the conductive substrate.
  • the conductive adhesive layer has a porous structure.
  • the conductive adhesive layer preferably contains metal particles, and Au, Pt, Ag, Ti, Ni, Bi, Cu, Ga, In, Pb, etc.
  • the conductive adhesive layer preferably contains a metal particle sintered body, and more preferably contains a silver particle sintered body. By using such a preferable conductive adhesive layer, it is possible to improve the adhesion between the electrode layer and the conductive substrate without impairing the electrical characteristics of the semiconductor element. Further, the conductive adhesive layer may be a single layer or a multilayer.
  • the thickness of the conductive adhesive layer is not particularly limited as long as it does not impair the object of the present invention, but is preferably 10 nm to 200 ⁇ m, and more preferably 30 nm to 50 ⁇ m. Further, the conductive adhesive layer is usually amorphous, but may contain auxiliary components such as crystals. The means for forming the conductive adhesive layer is not particularly limited, and may be a known coating means.
  • the conductive substrate is not particularly limited as long as it has conductivity, can support the semiconductor layer, and contains a Group 6 metal of the Periodic Table.
  • the Group 6 metal of the Periodic Table include chromium (Cr), molybdenum (Mo), and tungsten (W).
  • the Group 6 metal of the Periodic Table is preferably molybdenum (Mo).
  • the content of the Group 6 metal of the Periodic Table in the conductive substrate is not particularly limited as long as the object of the present invention is not impaired. In the embodiment of the present invention, when the weight ratio of the Group 6 metal of the periodic table in the conductive substrate is 0.09 or more, the warp of the entire semiconductor element is further reduced while improving the forward characteristics.
  • the conductive substrate contains two or more kinds of metals, and examples of such a combination of two or more kinds of metals include copper (Cu) -tungsten.
  • the conductive substrate further contains a Group 11 metal of the Periodic Table in addition to molybdenum.
  • the Group 11 metal in the periodic table examples include copper (Cu), silver (Ag), gold (Au), and the like.
  • the metal of Group 11 of the periodic law table is copper.
  • the conductive substrate contains molybdenum and copper
  • the Cu—Mo composite obtained by an impregnation method in which copper is impregnated in molybdenum powder as the conductive substrate. It is also preferable to use a substrate (hereinafter, also simply referred to as “Cu—Mo composite substrate”).
  • the conductive substrate may have a metal film on its surface.
  • the constituent metal of the metal film is, for example, one selected from gallium, iron, indium, aluminum, vanadium, titanium, chromium, rhodium, nickel, cobalt, zinc, magnesium, calcium, silicon, ittrium, strontium and barium. Two or more kinds of metals and the like can be mentioned.
  • the conductive substrate has a laminated structure in which at least one layer containing molybdenum and a layer containing a metal of Group 11 of the Periodic Table are laminated, and molybdenum is used. It is more preferable to form a laminated structure in which at least one layer of the containing layer and the metal of Group 11 of the periodic table are alternately laminated. In this case, the thickness of each layer is preferably 5 ⁇ m or more, and more preferably 10 ⁇ m or more.
  • the conductive substrate when the conductive substrate has the laminated structure, it is the semiconductor element that the uppermost layer and / or the lowermost layer in the laminated structure contains the Group 11 metal of the periodic table. It is preferable that the uppermost layer and the lowermost layer contain the Group 11 metal of the periodic table because the heat dissipation and the mountability can be further improved. Further, when the uppermost layer and / or the lowermost layer of the laminated structure contains the Group 11 metal of the periodic table in this way, the electrode layer and the conductive substrate are bonded to each other, and the conductive adhesive layer is formed. This can be done without using it, and the warpage and thermal resistance of the semiconductor element can be improved more effectively.
  • the copper-containing layer located on the outermost surface on the conductive substrate side in the electrode layer and the copper-containing layer located on the outermost surface on the electrode layer side in the laminated structure of the conductive substrate diffuse.
  • the electrode layer and the conductive substrate can be joined in an industrially advantageous manner without using the conductive adhesive layer.
  • the thickness of the conductive substrate is not particularly limited, but is preferably 200 ⁇ m or less because more excellent heat dissipation can be imparted without impairing the electrical characteristics of the semiconductor element. The following is more preferable.
  • the area of the conductive substrate is also not particularly limited, but in the embodiment of the present invention, it is preferably substantially the same as the area of the semiconductor layer.
  • substantially the same includes, for example, the case where the area of the conductive substrate and the area of the semiconductor layer are the same, and the ratio of the area of the conductive substrate to the area of the semiconductor layer is 0.9 to 1. Includes those within the range of 4.
  • the crystal of the crystalline semiconductor film may be regrown, or a different semiconductor layer, another electrode layer, or the like may be formed on the crystalline semiconductor film. It may be provided.
  • the other electrode layer is not particularly limited as long as it has conductivity, as long as it does not impair the object of the present invention.
  • the constituent material of the other electrode layer may be a conductive inorganic material or a conductive organic material.
  • the material of the other electrodes is metal.
  • Preferred examples of the metal include at least one metal selected from Groups 8 to 13 of the Periodic Table.
  • Examples of the metal of Group 8 to Group 10 of the Periodic Table include metals exemplified as the metal of Group 8 to Group 10 of the Periodic Table in the description of the electrode layer.
  • Examples of the Group 11 metal of the Periodic Table include copper (Cu), silver (Ag), and gold (Au).
  • Examples of the metal of Group 12 of the periodic table include zinc (ZN) and cadmium (Cd).
  • Examples of the metal of Group 13 of the periodic table include aluminum (Al), gallium (Ga), and indium (In).
  • the other electrode layer preferably comprises at least one metal selected from the Group 11 and Group 13 metals of the Periodic Table, selected from silver, copper, gold and aluminum. More preferably, it contains at least one metal.
  • the thickness of the other electrode layer is not particularly limited, but is preferably 1 nm to 500 ⁇ m, more preferably 10 nm to 100 ⁇ m, and most preferably 0.5 ⁇ m to 10 ⁇ m.
  • the means for forming the other electrode layer is not particularly limited, and may be a known means.
  • Specific examples of the means for forming the electrode layer or the other electrode layer include a dry method and a wet method.
  • the dry method include sputtering, vacuum deposition, and CVD.
  • the wet method include screen printing and die coating.
  • the semiconductor device of the present invention is useful for various semiconductor devices, and is particularly useful for power devices.
  • the semiconductor element has an electrode formed on one side of the semiconductor layer and a horizontal element (horizontal device) in which a current flows in the direction perpendicular to the film thickness direction of the semiconductor layer, and electrodes on both the front and back sides of the semiconductor layer.
  • a vertical element vertical device
  • the semiconductor element is suitable for both a horizontal device and a vertical device.
  • the semiconductor element examples include a Schottky barrier diode (SBD), a metal semiconductor field effect transistor (MESFET), a high electron mobility transistor (HEMT), a metal oxide film semiconductor field effect transistor (PWM), and an electrostatic induction transistor (MSFET).
  • SBD Schottky barrier diode
  • MESFET metal semiconductor field effect transistor
  • HEMT high electron mobility transistor
  • PWM metal oxide film semiconductor field effect transistor
  • MSFET electrostatic induction transistor
  • SIT junction field effect transistor
  • IGBT isolated gate type bipolar transistor
  • the semiconductor device is preferably an SBD, MOSFET, SIT, JFET or IGBT, more preferably an SBD, MOSFET or SIT, and most preferably an SBD.
  • FIG. 4 shows an example of a Schottky barrier diode (SBD) according to the present invention.
  • the SBD of FIG. 4 includes an n-type semiconductor layer 101a, an n + type semiconductor layer 101b, a conductive adhesive layer 106, a conductive substrate 107, a Schottky electrode 105a, and an ohmic electrode 105b.
  • the material of the Schottky electrode and the ohmic electrode may be a known electrode material, and the electrode material may be, for example, Al, Mo, Co, Zr, Sn, Nb, Fe, Cr, Ta, Ti, Au, etc.
  • Metals such as Pt, V, Mn, Ni, Cu, Hf, W, Ir, Zn, In, Pd, Nd or Ag or alloys thereof, tin oxide, zinc oxide, indium oxide, indium tin oxide (ITO), oxidation.
  • metal oxide conductive films such as indium tin oxide (IZO), organic conductive compounds such as polyaniline, polythiophene or polypyrrole, or mixtures thereof.
  • the Schottky electrode and the ohmic electrode can be formed by a known means such as a vacuum vapor deposition method or a sputtering method. More specifically, for example, when forming a Schottky electrode, a layer made of Mo and a layer made of Al are laminated, and the layer made of Mo and the layer made of Al are patterned using a photolithography technique. It can be done by.
  • a conductive holding substrate containing a Group 6 metal of the Periodic Table is used as the conductive substrate 107. Further, in the embodiment of the present invention, it is preferable to use a conductive substrate containing molybdenum and a metal of Group 11 of the Periodic Table, more preferably to use a conductive substrate containing molybdenum and copper, and a layer containing molybdenum. It is more preferable to use a conductive substrate composed of a laminated structure in which at least one layer containing copper is laminated. By using a conductive substrate having such a preferable configuration, it is possible to improve the forward characteristics of the semiconductor element and further reduce the thermal resistance of the entire semiconductor element, which is preferable. FIG.
  • FIG. 23 shows a preferred embodiment of the conductive substrate.
  • FIG. 23 shows a conductive substrate having a laminated structure in which at least one layer containing molybdenum and one layer containing copper are laminated (hereinafter, also referred to as “Cu—Mo laminated substrate”).
  • the metal layer 107a, the third metal layer 107c and the fifth metal layer 107e are made of copper, and the second metal layer 107b and the fourth metal layer 107d are made of molybdenum.
  • the conductive substrate a Si substrate, a Cu—Mo composite substrate (Mo content mass 70%, Cu content mass 30%) substrate, and a Cu—Mo laminated substrate are used, and the structure conforming to the SBD shown in FIG. 4 is used. Thermal resistance simulation was performed.
  • the thickness of the conductive substrate was 100 ⁇ m.
  • FIG. 20 shows the results when the conductive substrate is a Si substrate
  • FIG. 21 shows the results when the conductive substrate is a Cu—Mo composite substrate (Mo content mass 70%, Cu content mass 30%).
  • the case where the substrate is a Cu—Mo laminated substrate is shown in FIG. 22 respectively.
  • the thermal resistance of the semiconductor element can be reduced as compared with the case where the Si substrate is used. Do you get it.
  • an oxide semiconductor for example, gallium oxide, etc.
  • the content of molybdenum in the conductive substrate is 9%, 24%, and 30% by weight, and the semiconductor is used.
  • the amount of warpage of the semiconductor device when the device was manufactured was measured. The result is shown in FIG.
  • FIG. 23 As is clear from FIG. 23, as is clear from FIG. 24, it can be seen that the amount of warpage of the entire semiconductor element can be reduced by adjusting the content of molybdenum in the conductive substrate.
  • the molybdenum content can be appropriately adjusted depending on the thickness of the semiconductor layer in the semiconductor device, the thickness of the layer containing the Group 11 metal of the Periodic Table, and the like.
  • the warp of the semiconductor element can be reduced more effectively. Further, by adjusting the thickness, material, and the like of each layer by using the laminated substrate as shown in FIG. 23, the warp of the semiconductor element can be reduced more satisfactorily.
  • FIG. 5 shows an example of a Schottky barrier diode (SBD) according to the present invention.
  • the SBD of FIG. 5 further includes an insulator layer 104 in addition to the configuration of the SBD of FIG. More specifically, it includes an n-type semiconductor layer 101a, an n + type semiconductor layer 101b, a conductive adhesive layer 106, a conductive substrate 107, a shotkey electrode 105a, an ohmic electrode 105b, and an insulator layer 104.
  • Examples of the material of the insulator layer 104 include GaO, AlGaO, InAlGaO, AlInZnGaO4, AlN, Hf2O3, SiN, SiON, Al2O3, MgO, GdO, SiO2 or Si3N4. It preferably has a corundum structure. By using an insulator having a corundum structure for the insulator layer, the function of the semiconductor property at the interface can be satisfactorily exhibited.
  • the insulator layer 104 is provided between the n-type semiconductor layer 101 and the Schottky electrode 105a.
  • the insulator layer can be formed by a known means such as a sputtering method, a vacuum vapor deposition method or a CVD method.
  • the formation and materials of the Schottky electrode and the ohmic electrode are the same as in the case of the SBD of FIG. 4, for example, using known means such as a sputtering method, a vacuum vapor deposition method, a crimping method, and a CVD method, for example.
  • Metals such as Al, Mo, Co, Zr, Sn, Nb, Fe, Cr, Ta, Ti, Au, Pt, V, Mn, Ni, Cu, Hf, W, Ir, Zn, In, Pd, Nd or Ag Or these alloys, metal oxide conductive films such as tin oxide, zinc oxide, indium oxide, indium tin oxide (ITO), indium zinc oxide (IZO), organic conductive compounds such as polyaniline, polythiophene or polypyrrole, or An electrode made of a mixture of these can be formed.
  • the SBD of FIG. 5 is further excellent in insulation characteristics and has higher current controllability than the SBD of FIG.
  • FIG. 6 shows an example of the case where the semiconductor element of the present invention is a MOSFET.
  • the MOSFET in FIG. 6 is a trench-type MOSFET, which is an n-type semiconductor layer 131a, an n + type semiconductor layers 131b and 131c, a conductive adhesive layer 136, a conductive substrate 137, a gate insulating film 134, a gate electrode 135a, and a source electrode. It includes a 135b and a drain electrode 135c.
  • a conductive adhesive layer 136 having a thickness of 50 nm to 50 ⁇ m is formed on the conductive substrate 137.
  • a drain electrode 135c is formed on the conductive adhesive layer 136.
  • an n + type semiconductor layer 131b having a thickness of 100 nm to 100 ⁇ m is formed, and on the n + type semiconductor layer 131b, for example, an n-type semiconductor layer 131a having a thickness of 100 nm to 100 ⁇ m is formed. Is formed.
  • an n + type semiconductor layer 131c is formed on the n ⁇ type semiconductor layer 131a, and a source electrode 135b is formed on the n + type semiconductor layer 131c.
  • a plurality of trench grooves having a depth that penetrates the n + type semiconductor layer 131c and reaches the middle of the n ⁇ type semiconductor layer 131a are formed.
  • a gate electrode 135a is embedded and formed via a gate insulating film 134 having a thickness of 10 nm to 1 ⁇ m.
  • a voltage is applied between the source electrode 135b and the drain electrode 135c, and a positive voltage is applied to the gate electrode 135a with respect to the source electrode 135b.
  • a channel layer is formed on the side surface of the semiconductor layer 131a, and electrons are injected into the n ⁇ type semiconductor layer to turn on.
  • the voltage of the gate electrode is set to 0V, the channel layer cannot be formed, the n-type semiconductor layer 131a is filled with the depletion layer, and the turn-off occurs.
  • FIG. 7 shows a part of the manufacturing process of the MOSFET of FIG.
  • an etching mask is provided in a predetermined region of the n ⁇ type semiconductor layer 131a and the n + type semiconductor layer 131c, the etching mask is used as a mask, and reactive ions are further prepared.
  • anisotropic etching is performed by an etching method or the like to form a trench groove having a depth extending from the surface of the n + type semiconductor layer 131c to the middle of the n ⁇ type semiconductor layer 131a. .. Then, as shown in FIG.
  • a gate having a thickness of, for example, 50 nm to 1 ⁇ m is used on the side surface and the bottom surface of the trench groove by using known means such as a thermal oxidation method, a vacuum vapor deposition method, a sputtering method, and a CVD method.
  • a gate electrode material such as polysilicon is formed in the trench groove by a CVD method, a vacuum vapor deposition method, a sputtering method, or the like to be equal to or less than the thickness of the n ⁇ type semiconductor layer.
  • the source electrode 135b is formed on the n + type semiconductor layer 131c and the drain electrode 135c is formed on the n + type semiconductor layer 131b by using known means such as a vacuum vapor deposition method, a sputtering method, and a CVD method.
  • Power MOSFETs can be manufactured.
  • the electrode materials of the source electrode and the drain electrode may be known electrode materials, respectively, and the electrode materials include, for example, Al, Mo, Co, Zr, Sn, Nb, Fe, Cr, Ta, and Ti.
  • FIG. 6 shows an example of a trench-type vertical MOSFET
  • the embodiment of the present invention is not limited to this, and can be applied to various MOSFET forms.
  • the depth of the trench groove in FIG. 6 may be dug down to a depth reaching the bottom surface of the n-type semiconductor layer 131a to reduce the series resistance.
  • FIG. 8 shows an example of the case where the semiconductor device of the present invention is a SIT.
  • the SIT of FIG. 8 includes an n-type semiconductor layer 141a, an n + type semiconductor layer 141b and 141c, a conductive adhesive layer 146, a conductive substrate 147, a gate electrode 145a, a source electrode 145b and a drain electrode 145c.
  • a conductive support layer 147 having a thickness of 100 nm to 100 ⁇ m is formed on the drain electrode 145c, and a conductive adhesive layer 146 having a thickness of 50 nm to 50 ⁇ m is formed on the conductive support layer 147.
  • a conductive adhesive layer 146 having a thickness of 50 nm to 50 ⁇ m is formed on the conductive support layer 147.
  • an n + type semiconductor layer 141b having a thickness of 100 nm to 100 ⁇ m is formed on the conductive adhesive layer 146, and an n-type semiconductor having a thickness of 100 nm to 100 ⁇ m, for example, is formed on the n + type semiconductor layer 141b.
  • Layer 141a is formed.
  • an n + type semiconductor layer 141c is formed on the n ⁇ type semiconductor layer 141a, and a source electrode 145b is formed on the n + type semiconductor layer 141c.
  • n-type semiconductor layer 141a a plurality of trench grooves having a depth that penetrates the n + semiconductor layer 131c and reaches a depth in the middle of the n-semiconductor layer 131a are formed.
  • a gate electrode 145a is formed on the n-type semiconductor layer in the trench groove.
  • SIT in FIG. 8 When the SIT in FIG. 8 is on, a voltage is applied between the source electrode 145b and the drain electrode 145c, and a positive voltage is applied to the gate electrode 145a with respect to the source electrode 145b.
  • a channel layer is formed in the semiconductor layer 141a, and electrons are injected into the n ⁇ type semiconductor layer to turn on. In the off state, when the voltage of the gate electrode is set to 0V, the channel layer cannot be formed, the n-type semiconductor layer is filled with the depletion layer, and the turn-off occurs.
  • the SIT of FIG. 8 can be manufactured in the same manner as the MOSFET of FIG. 7. More specifically, for example, an etching mask is provided in a predetermined region of the n-type semiconductor layer 141a and the n + type semiconductor layer 141c, and the etching mask is used as a mask to perform anisotropic etching by, for example, a reactive ion etching method. Therefore, a trench groove having a depth extending from the surface of the n + type semiconductor layer 141c to the middle of the n ⁇ type semiconductor layer is formed.
  • a gate electrode material such as polysilicon is formed in the trench groove by a CVD method, a vacuum vapor deposition method, a sputtering method, or the like to be equal to or less than the thickness of the n-type semiconductor layer.
  • a source electrode 145b is formed on the n + type semiconductor layer 141c and a drain electrode 145c on the n + type semiconductor layer 141b by using known means such as a vacuum vapor deposition method, a sputtering method, and a CVD method, the source electrode 145b is formed on the n + type semiconductor layer 141c. SIT can be manufactured.
  • the electrode materials of the source electrode and the drain electrode may be known electrode materials, respectively, and the electrode materials include, for example, Al, Mo, Co, Zr, Sn, Nb, Fe, Cr, Ta, and Ti. , Au, Pt, V, Mn, Ni, Cu, Hf, W, Ir, Zn, In, Pd, Nd or Ag or other metals or alloys thereof, tin oxide, zinc oxide, indium oxide, indium tin oxide (ITO). ), Metal oxide conductive film such as indium tin oxide (IZO), polyaniline, polythiophene or polypyrro- Examples thereof include organic conductive compounds such as le, or mixtures thereof.
  • the electrode materials include, for example, Al, Mo, Co, Zr, Sn, Nb, Fe, Cr, Ta, and Ti. , Au, Pt, V, Mn, Ni, Cu, Hf, W, Ir, Zn, In, Pd, Nd or Ag or other metals or alloys thereof, tin oxide, zinc
  • a p-type semiconductor is not used, but in the embodiment of the present invention, the present invention is not limited to this, and a p-type semiconductor may be used. Examples of using a p-type semiconductor are shown in FIGS. 9 to 11. These semiconductor devices can be manufactured in the same manner as in the above example.
  • the p-type semiconductor may be the same material as the n-type semiconductor and may contain a p-type dopant or may be a different p-type semiconductor.
  • the semiconductor element is particularly useful for power devices.
  • the semiconductor element include a diode (for example, a PN diode, a Schottky barrier diode, a junction barrier Schottky diode, etc.) or a transistor (for example, a MESFET), and among them, a diode is preferable, and a Schottky barrier diode is preferable. (SBD) is more preferable.
  • the semiconductor element in the embodiment of the present invention is suitably used as a semiconductor device by joining to a lead frame, a circuit board, a heat dissipation board, or the like by a joining member based on a conventional method, and in particular, a power module. , And more preferably used as a semiconductor system using, for example, a power supply device.
  • a suitable example of the semiconductor device is shown in FIG. In the semiconductor device of FIG. 15, both sides of the semiconductor element 500 are bonded to the lead frame, the circuit board, or the heat dissipation board 502 by solder 501, respectively. With this configuration, it is possible to obtain a semiconductor device having excellent heat dissipation.
  • the periphery of the joining member such as solder is sealed with a resin.
  • the above-mentioned semiconductor element or semiconductor device of the present invention can be applied to a power conversion device such as an inverter or a converter in order to exert the above-mentioned functions. More specifically, it can be applied as a diode built in an inverter or a converter, a cyclist as a switching element, a power transistor, an IGBT (Insulated Gate Bipolar Transistor), a MOSFET (Metal-Oxide-Semiconductor Field Effect Transistor), or the like. can.
  • FIG. 16 is a block configuration diagram showing an example of a control system using a semiconductor element or a semiconductor device according to an embodiment of the present invention
  • FIG. 17 is a circuit diagram of the control system, particularly for an electric vehicle. It is a control system suitable for mounting.
  • the control system 500 includes a battery (power supply) 501, a boost converter 502, a step-down converter 503, an inverter 504, a motor (drive target) 505, and a drive control unit 506, which are mounted on an electric vehicle. It becomes.
  • the battery 501 is composed of a storage battery such as a nickel hydrogen battery or a lithium ion battery, and stores electric power by charging at a power supply station or regenerating energy during deceleration, and is required for the operation of the traveling system and the electrical system of an electric vehicle. It can output a DC voltage.
  • the boost converter 502 is a voltage converter equipped with, for example, a chopper circuit, and boosts a DC voltage of, for example, 200 V supplied from the battery 501 to, for example, 650 V by the switching operation of the chopper circuit, and outputs the DC voltage to a traveling system such as a motor. be able to.
  • the step-down converter 503 is also a voltage converter equipped with a chopper circuit, but by stepping down the DC voltage of, for example, 200 V supplied from the battery 501 to, for example, about 12 V, a power window, power steering, or an in-vehicle electric device can be used. It can be output to the electrical system including.
  • the inverter 504 converts the DC voltage supplied from the boost converter 502 into a three-phase AC voltage by a switching operation and outputs it to the motor 505.
  • the motor 505 is a three-phase AC motor constituting the traveling system of the electric vehicle, and is rotationally driven by the three-phase AC voltage output from the inverter 504. Communicate to.
  • the drive control unit 506 has the function of a controller equipped with a calculation unit such as a CPU (Central Processing Unit) and a data storage unit such as a memory, and generates a control signal using the input measurement signal to the inverter 504. By outputting as a feedback signal, the switching operation by the switching element is controlled.
  • a calculation unit such as a CPU (Central Processing Unit)
  • a data storage unit such as a memory
  • the AC voltage applied to the motor 505 by the inverter 504 is instantaneously corrected, so that the operation control of the electric vehicle can be accurately executed, and the safe and comfortable operation of the electric vehicle is realized. It is also possible to control the output voltage to the inverter 504 by giving the feedback signal from the drive control unit 506 to the boost converter 502.
  • FIG. 17 is a circuit configuration excluding the step-down converter 503 in FIG. 16, that is, a circuit configuration showing only a configuration for driving the motor 505.
  • the semiconductor device of the present invention is used for switching control by being adopted in a boost converter 502 and an inverter 504, for example, as a Schottky barrier diode.
  • the boost converter 502 is incorporated in a chopper circuit to perform chopper control
  • the inverter 504 is incorporated in a switching circuit including an IGBT to perform switching control.
  • An inductor (coil, etc.) is interposed in the output of the battery 501 to stabilize the current, and a capacitor (electrolytic capacitor, etc.) is interposed between the battery 501, the boost converter 502, and the inverter 504. We are trying to stabilize the voltage.
  • a calculation unit 507 composed of a CPU (Central Processing Unit) and a storage unit 508 composed of a non-volatile memory are provided in the drive control unit 506.
  • the signal input to the drive control unit 506 is given to the calculation unit 507, and a feedback signal for each semiconductor element is generated by performing necessary calculations.
  • the storage unit 508 temporarily holds the calculation result by the calculation unit 507, stores physical constants and functions required for drive control in the form of a table, and appropriately outputs them to the calculation unit 507.
  • a known configuration can be adopted for the calculation unit 507 and the storage unit 508, and the processing capacity thereof and the like can be arbitrarily selected.
  • a diode, a switching element such as a thyristor, a power transistor, an IGBT, a MOSFET, or the like is used for the switching operation of the boost converter 502, the step-down converter 503, and the inverter 504. .
  • gallium oxide (Ga 2 O 3 ), particularly corundum type gallium oxide ( ⁇ -Ga 2 O 3 ), as the material for these semiconductor devices the switching characteristics are significantly improved. Further, by applying the semiconductor device or the like according to the present invention, extremely good switching characteristics can be expected, and further miniaturization and cost reduction of the control system 500 can be realized.
  • each of the boost converter 502, the step-down converter 503, and the inverter 504 can be expected to have the effect of the present invention, and any one of them, any combination of two or more, or a drive control unit 506 is also included.
  • the effect of the present invention can be expected in any of the above.
  • the control system 500 described above can be applied not only to the control system of an electric vehicle by applying the semiconductor device of the present invention, but also to a control system for all purposes such as stepping up / down the power from a DC power source and converting power from DC to AC. It is possible to apply to. It is also possible to use a power source such as a solar cell as the battery.
  • FIG. 18 is a block configuration diagram showing another example of a control system using a semiconductor element or a semiconductor device according to an embodiment of the present invention
  • FIG. 19 is a circuit diagram of the control system, which operates with power from an AC power source. It is a control system suitable for mounting on infrastructure equipment and home appliances.
  • the control system 600 inputs electric power supplied from an external, for example, a three-phase AC power supply (power supply) 601 and includes an AC / DC converter 602, an inverter 604, a motor (drive target) 605, and the like. It has a drive control unit 606, which can be mounted on various devices (described later).
  • the three-phase AC power supply 601 is, for example, a power generation facility of an electric power company (thermal power plant, hydropower plant, geothermal power plant, nuclear power plant, etc.), and its output is supplied as an AC voltage while being stepped down via a substation. To. Further, it is installed in a building or a nearby facility in the form of a private power generator or the like and is supplied by a power cable.
  • the AC / DC converter 602 is a voltage conversion device that converts an AC voltage into a DC voltage, and converts an AC voltage of 100V or 200V supplied from the three-phase AC power supply 601 into a predetermined DC voltage. Specifically, it is converted into a commonly used desired DC voltage such as 3.3V, 5V, or 12V by voltage conversion. When the drive target is a motor, conversion to 12V is performed. It is also possible to adopt a single-phase AC power supply instead of the three-phase AC power supply, and in that case, if the AC / DC converter has a single-phase input, the same system configuration can be obtained.
  • the inverter 604 converts the DC voltage supplied from the AC / DC converter 602 into a three-phase AC voltage by a switching operation and outputs it to the motor 605.
  • the form of the motor 604 differs depending on the control target, but when the control target is a train, it drives a wheel, when it is a factory facility, it drives a pump or various power sources, and when it is a home appliance, it drives a compressor or the like. It is a three-phase AC motor, which is rotationally driven by a three-phase AC voltage output from the inverter 604, and transmits the rotational driving force to a drive target (not shown).
  • the inverter 604 is no longer required for the control system 600, and as shown in FIG. 18, a DC voltage is supplied from the AC / DC converter 602 to the drive target.
  • a DC voltage of 3.3 V is supplied to a personal computer or the like, and a DC voltage of 5 V is supplied to an LED lighting device or the like.
  • the drive control unit 606 uses various sensors (not shown), measured values such as the rotation speed and torque of the drive target, the temperature and flow rate of the surrounding environment of the drive target, etc. to measure these measurement signals, and these measurement signals are input to the drive control unit 606. At the same time, the output voltage value of the inverter 604 is also input to the drive control unit 606. Based on these measurement signals, the drive control unit 606 gives a feedback signal to the inverter 604 and controls the switching operation by the switching element. As a result, the AC voltage applied to the motor 605 by the inverter 604 is instantaneously corrected, so that the operation control of the drive target can be accurately executed, and the stable operation of the drive target is realized. Further, as described above, when the drive target can be driven by a DC voltage, it is also possible to perform feedback control of the AC / DC converter 602 instead of the feedback to the inverter.
  • FIG. 19 shows the circuit configuration of FIG.
  • the semiconductor device of the present invention is used for switching control by being adopted in an AC / DC converter 602 and an inverter 604, for example, as a Schottky barrier diode.
  • an AC / DC converter 602 for example, a Schottky barrier diode having a circuit configuration in a bridge shape is used, and DC conversion is performed by converting and rectifying the negative voltage component of the input voltage to a positive voltage.
  • the inverter 604 is incorporated in the switching circuit of the IGBT to perform switching control.
  • An inductor (coil, etc.) is interposed between the three-phase AC power supply 601 and the AC / DC converter 602 to stabilize the current, and a capacitor (electrolytic capacitor) is placed between the AC / DC converter 602 and the inverter 604. Etc.) are intervened to stabilize the voltage.
  • a calculation unit 607 composed of a CPU and a storage unit 608 composed of a non-volatile memory are provided in the drive control unit 606.
  • the signal input to the drive control unit 606 is given to the calculation unit 607, and a feedback signal for each semiconductor element is generated by performing necessary calculations.
  • the storage unit 608 temporarily holds the calculation result by the calculation unit 607, stores physical constants and functions required for drive control in the form of a table, and appropriately outputs them to the calculation unit 607.
  • a known configuration can be adopted for the calculation unit 607 and the storage unit 608, and the processing capacity thereof and the like can be arbitrarily selected.
  • the rectifying operation and switching operation of the AC / DC converter 602 and the inverter 604 are performed by a diode, a thyristor which is a switching element, and a power transistor.
  • IGBT, MOSFET and the like are used.
  • gallium oxide (Ga 2 O 3 ), particularly corundum type gallium oxide ( ⁇ -Ga 2 O 3 ), as the material for these semiconductor devices the switching characteristics are improved. Further, by applying the semiconductor film or the semiconductor device according to the present invention, extremely good switching characteristics can be expected, and further miniaturization and cost reduction of the control system 600 can be realized.
  • each of the AC / DC converter 602 and the inverter 604 can be expected to have the effect of the present invention, and the effect of the present invention can be expected in any one or combination of these, or in any form including the drive control unit 606. Can be expected.
  • the motor 605 is illustrated as a drive target in FIGS. 18 and 19, the drive target is not necessarily limited to those that operate mechanically, and many devices that require an AC voltage can be targeted.
  • the control system 600 it can be applied as long as the drive target is driven by inputting power from an AC power source, and it can be applied to infrastructure equipment (for example, power equipment such as buildings and factories, communication equipment, traffic control equipment, water and sewage treatment). It can be installed for drive control of equipment such as equipment, system equipment, labor-saving equipment, trains, and home appliances (for example, refrigerators, washing machines, personal computers, LED lighting equipment, video equipment, audio equipment, etc.). can.
  • the mist CVD device 1 used in this embodiment will be described with reference to FIG.
  • the mist CVD device 1 includes a carrier gas source 2a for supplying a carrier gas, a flow control valve 3a for adjusting the flow rate of the carrier gas sent out from the carrier gas source 2a, and a carrier for supplying the carrier gas (diluted).
  • It includes a hot plate 8 installed inside, and an discharge port 11 for discharging mist, droplets, and exhaust gas after a thermal reaction.
  • the substrate 10 is installed on the hot plate 8.
  • n-type semiconductor layer was formed on a sapphire substrate (substrate 10) using the mist CVD apparatus shown in FIG.
  • n + type semiconductor layer Except for the fact that tin was used as the dopant, the above 1-2. In the same manner as above, an n + type semiconductor layer was formed on the n ⁇ type semiconductor layer. When the phase of the obtained film was identified using an XRD diffractometer, the obtained film was ⁇ -Ga 2 O 3 .
  • the Ti layer and the Au layer were laminated by sputtering on the n + type semiconductor layer of the laminate obtained in 1.
  • the thickness of the Ti layer was 70 nm, and the thickness of the Au layer was 30 nm.
  • a Cu—Mo composite substrate (Mo content 70%, Cu content 30%) was laminated on the ohmic electrode of the laminate obtained in 1) via a conductive adhesive layer made of a silver particle sintered body. ..
  • the thickness of the conductive substrate was 200 ⁇ m.
  • a Co film (thickness 100 nm), a Ti film (50 nm) and an Al film (thickness 5 ⁇ m) were formed on the second n-type semiconductor layer of the laminate obtained in 1 above by EB vapor deposition, respectively, and shot key. It was used as an electrode.
  • Example 1 An SBD was produced according to Example 1 except that a Si substrate was used as the conductive substrate.
  • Example 1 The IV characteristics of the semiconductor devices (SBDs) obtained in Example 1 and Comparative Example 1 were evaluated. The results are shown in FIGS. 13 and 14, respectively. From FIGS. 13 and 14, it can be seen that the Schottky barrier diode of Example 1 has excellent electrical characteristics. Further, even when the Cu—Mo laminated substrate shown in FIG. 23 is used as the conductive substrate, the same electrical characteristics as in Example 1 can be obtained.
  • the semiconductor device of the present invention can be used in all fields such as semiconductors (for example, compound semiconductor electronic devices, etc.), electronic parts / electrical equipment parts, optical / electrophotographic-related equipment, industrial parts, etc., but is particularly useful for power devices. be.

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  • Power Engineering (AREA)
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  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Computer Hardware Design (AREA)
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Abstract

La présente invention concerne : un élément semi-conducteur qui présente des caractéristiques avant améliorées, et est particulièrement utile pour des dispositifs d'alimentation ; et un dispositif à semi-conducteur. L'invention concerne également un élément semi-conducteur qui est une structure multicouche qui comprend une couche semi-conductrice qui contient, en tant que composant principal, un semi-conducteur à oxyde cristallin (par exemple, α-Ga2O3), une couche d'électrode qui est superposée sur la couche semi-conductrice, et un substrat conducteur qui est superposé sur la couche d'électrode directement ou avec une autre couche interposée entre ceux-ci, le substrat conducteur contenant un métal du groupe 6 du tableau périodique; et un dispositif à semi-conducteur qui est pourvu de cet élément semi-conducteur.
PCT/JP2021/029577 2020-08-07 2021-08-10 Élément à semi-conducteur et dispositif à semi-conducteur WO2022030650A1 (fr)

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CN118431270A (zh) * 2024-07-01 2024-08-02 深圳市港祥辉电子有限公司 一种场截止型氧化镓igbt器件及其制备方法

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JP2007165690A (ja) * 2005-12-15 2007-06-28 Fuji Electric Holdings Co Ltd ヒートスプレッダと金属板との接合方法
JP2013046071A (ja) * 2011-08-22 2013-03-04 Lg Innotek Co Ltd 発光素子パッケージ及びこれを含むライトユニット
JP2015026831A (ja) * 2013-06-21 2015-02-05 株式会社半導体エネルギー研究所 半導体装置及びその作製方法
JP2017157661A (ja) * 2016-03-01 2017-09-07 出光興産株式会社 半導体装置
WO2020079971A1 (fr) * 2018-10-15 2020-04-23 株式会社デンソー Dispositif à semi-conducteur
JP2020107636A (ja) * 2018-12-26 2020-07-09 株式会社Flosfia 結晶性酸化物膜

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Publication number Priority date Publication date Assignee Title
JP2007165690A (ja) * 2005-12-15 2007-06-28 Fuji Electric Holdings Co Ltd ヒートスプレッダと金属板との接合方法
JP2013046071A (ja) * 2011-08-22 2013-03-04 Lg Innotek Co Ltd 発光素子パッケージ及びこれを含むライトユニット
JP2015026831A (ja) * 2013-06-21 2015-02-05 株式会社半導体エネルギー研究所 半導体装置及びその作製方法
JP2017157661A (ja) * 2016-03-01 2017-09-07 出光興産株式会社 半導体装置
WO2020079971A1 (fr) * 2018-10-15 2020-04-23 株式会社デンソー Dispositif à semi-conducteur
JP2020107636A (ja) * 2018-12-26 2020-07-09 株式会社Flosfia 結晶性酸化物膜

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN118431270A (zh) * 2024-07-01 2024-08-02 深圳市港祥辉电子有限公司 一种场截止型氧化镓igbt器件及其制备方法

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