SEMICONDUCTOR DEVICE, OR CRYSTAL

• US 20150194479A1
• Filed: 09/24/2013
• Published: 07/09/2015
• Est. Priority Date: 09/28/2012
• Status: Active Grant

• Current Assignee: Filosofia Inc.
• Original Assignee: Filosofia Inc.
• Inventors: Kaneko, Kentaro, Hitora, Toshimi, Hirao, Takashi
• Granted Patent: US 9,711,590 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: C30B 25/02 Epitaxial-layer growth
• CPC Class Codes: C30B 29/20 Aluminium oxides
• CPC Class Codes: C30B 29/22 Complex oxides
• CPC Class Codes: H01L 21/0237 Materials
• CPC Class Codes: H01L 21/0242 Crystalline insulating materials
• CPC Class Codes: H01L 21/02488 Insulating materials
• CPC Class Codes: H01L 21/02565 Oxide semiconducting materials not being Group 12/16 materials, e.g. ternary compounds
• CPC Class Codes: H01L 21/02609 Crystal orientation
• CPC Class Codes: H01L 21/0262 Reduction or decomposition of gaseous compounds, e.g. CVD
• CPC Class Codes: H01L 21/02628 using solutions
• CPC Class Codes: H01L 29/04 characterised by their crystalline structure, e.g. polycrystalline, cubic or particular orientation of crystalline planes characterised by physical imperfections H01L29/30
• CPC Class Codes: H01L 29/24 including, apart from doping materials or other impurities, only semiconductor materials not provided for in groups H01L29/16, H01L29/18, H01L29/20, H01L29/22 including organic materials H10K99/00

Abstract

There is provided a semiconductor device including corundum crystal films of good quality. There is provided a semiconductor device including a base substrate, a semiconductor layer, and an insulating film each having a corundum crystal structure. Materials having a corundum crystal structure include many types of oxide films capable of functioning as an insulating film. Since all the base substrate, the semiconductor layer, and the insulating film have a corundum crystal structure, it is possible to achieve a semiconductor layer and an insulating film of good quality on the base substrate.

Claims

1. A semiconductor device or a crystal comprising:

a base substrate;

a semiconductor layer; and

an insulating film, wherein

the semiconductor layer and the insulating film are disposed on the base substrate in this order or in an order reverse to this order, and

all the base substrate, the semiconductor layer, and the insulating film have a corundum crystal structure.

2. The semiconductor device or the crystal of claim 1, wherein all the base substrate, the semiconductor layer, and the insulating film are formed from one of sapphire, gallium oxide, indium oxide, chrome oxide, ferric oxide, titanium oxide, vanadium oxide, and cobalt oxide, or a mixed crystal of two or more thereof.

3. The semiconductor device or the crystal of claim 1,

wherein all the base substrate, the semiconductor layer, and the insulating film are formed from the same semiconductor material or composition, or semiconductor materials or compositions having lattice constants which differ from each other by 15% or less.

4. The semiconductor device or the crystal of claim 3, wherein all the base substrate, the semiconductor layer, and the insulating film are formed from α

-phase aluminum gallium oxide represented by Al_XGa_YO₃ where 0≦

X≦

2, 0≦

Y≦

2, and X+Y=1.5 to 2.5.

5. The semiconductor device or the crystal of claim 1, wherein

at least one of the base substrate, the semiconductor layer, and the insulating film has a different composition.

6. The semiconductor device or the crystal of claim 1, wherein

the base substrate and the insulating film are formed from one of sapphire, gallium oxide, indium oxide, chrome oxide, ferric oxide, titanium oxide, vanadium oxide, and cobalt oxide, or a mixed crystal of two or more thereof, and

the semiconductor layer is formed from α

-In_X1Al_Y1Ga_Z1O₃ where 0≦

X1≦

2, 0≦

Y1≦

2, 0≦

Z1≦

2, and X1+Y1+Z1=1.5 to 2.5.

7. The semiconductor device or the crystal of claim 6, wherein 0.1≦

X1 or 0.1≦

Z1.

8. The semiconductor device or the crystal of claim 6, wherein 0.1≦

X1 and 0.1≦

Z1.

9. The semiconductor device or the crystal of claim 6, wherein

the base substrate is formed from α

-sapphire, and

the insulating film is formed from α

-Al_Y2Ga_Z2O₃ where 0≦

Y2≦

2, 0≦

Z2≦

2, and Y2+Z2=1.5 to 2.5.

10. The semiconductor device or the crystal of claim 9, wherein 0.1≦

X2 and 0.1≦

Y2.

11. The semiconductor device or the crystal of claim 1, wherein

a crystalline stress relaxation layer having a corundum crystal structure is disposed between the base substrate and the semiconductor layer.

12. The semiconductor device or the crystal of claim 11, wherein

the base substrate is formed from α

-sapphire,

the crystalline stress relaxation layer comprises one or more layers and is formed from α

-Al_X1Ga_Y1O₃ where 0≦

X1≦

2, 0≦

Y1≦

2, and X1+Y1=1.5 to 2.5 and where the amount of Al is gradually reduced from the base substrate toward the semiconductor layer,

the semiconductor layer is formed from α

-In_X2Al_Y2Ga_Z2O₃ where 0≦

X2≦

2, 0≦

Y2≦

2, 0≦

Z2≦

2, and X2+Y2+Z2=1.5 to 2.5, and the insulating film is formed from α

-Al_X3Ga_Y3O₃ where 0≦

X3≦

2, 0≦

Y3≦

2, and X3+Y3=1.5 to 2.5.

13. The semiconductor device or the crystal of claim 1, wherein

a cap layer comprising at least one of elements included in the semiconductor layer and the insulating film is disposed between the semiconductor layer and the insulating film.

14. The semiconductor device or the crystal of claim 13, wherein

the base substrate is formed from α

-sapphire,

the semiconductor layer is formed from impurity-doped α

-In_X2Al_Y2Ga_Z2O₃ where 0≦

X2≦

2, 0≦

Y2≦

2, 0≦

Z2≦

2, and X2+Y2+Z2=1.5 to 2.5,

the cap layer is formed from α

-Al_X3Ga_Y3O₃ where 0≦

X3≦

2, 0≦

Y3≦

2, and X3+Y3=1.5 to 2.5 and where the amount of Al is gradually increased from the semiconductor layer toward the insulating film, and

the insulating film is formed from α

-Al_X4Ga_Y4O₃ where 0≦

X4≦

2, 0≦

Y4≦

2, and X4+Y4=1.5 to 2.5.

15. The semiconductor device or the crystal of claim 14, wherein

a crystalline stress relaxation layer having a corundum crystal structure is disposed between the base substrate and the semiconductor layer, and

the crystalline stress relaxation layer comprises one or more layers and is formed from α

-Al_X1Ga_Y1O₃ where 0≦

X1≦

2, 0≦

Y1≦

2, and X1+Y1=1.5 to 2.5 and where the amount of Al is gradually reduced from the base substrate toward the semiconductor layer.

16. The semiconductor device or the crystal of claim 1, wherein

a structural phase transition prevention layer comprising at least one of elements included in the semiconductor layer and the insulating film is disposed between the semiconductor layer and the insulating film.

17. The semiconductor device or the crystal of claim 16, wherein

the semiconductor layer is formed from impurity-doped α

-In_X1Al_Y1Ga_Z1O₃ where 0≦

X1≦

2, 0≦

Y1≦

2, 0≦

Z1≦

2, and X1+Y1+Z1=1.5 to 2.5,

the structural phase transition prevention layer is formed from α

-Al_X2Ga_Y2O₃ where 0≦

X2≦

2, 0≦

Y2≦

2, and X2+Y2=1.5 to 2.5 and where the amount of Al is gradually increased from the semiconductor layer toward the insulating film, and

the insulating film is formed from α

-Al_X3Ga_Y3O₃ where 0≦

X3≦

2, 0≦

Y3≦

2, and X3+Y3=1.5 to 2.5.

18. A method for manufacturing the semiconductor device or the crystal of claim 1, the method comprising

a step of providing a raw material mist to a film forming chamber, the raw material mist being generated by atomizing a raw material solution, the raw material solution being obtained by dissolving, in a solvent, a solute which is a raw material for the semiconductor layer and the insulating film.

19. The method of claim 18, further comprising a step of making the raw material mist react in the film forming chamber to form the semiconductor layer and the insulating film on the base substrate.

20. The method of claim 18, wherein

at least one of the semiconductor layer and the insulating film comprises a mixed crystal film, and

the mixed crystal film is formed from a raw material solution obtained by dissolving two or more solutes in a solvent.

21. The method of claim 18, wherein

at least one of the semiconductor layer and the insulating film comprises a mixed crystal film, and the

the mixed crystal film is formed by simultaneously injecting raw material mists into a film forming chamber, the raw material mists being generated by atomizing two or more raw material solutions separately.

22. A semiconductor device or a crystal comprising:

a support substrate;

a semiconductor layer; and

an insulating film, wherein

the semiconductor layer and the insulating film are disposed on the support substrate in this order or in a order reverse to this order,

the support substrate has or does not have a corundum crystal structure,

both the semiconductor layer and the insulating film have a corundum crystal structure, and

a joining layer joining the support substrate and a corundum crystal is disposed between the support substrate and the semiconductor layer.

23. The semiconductor device or the crystal of claim 22, wherein

the support substrate is formed from one of a SiC substrate, a Si substrate, a metal substrate, a ceramic substrate, and a glass substrate.

24. The semiconductor device or the crystal of claim 22, wherein

the joining layer is formed from a silicon oxide film.

25. A method for manufacturing a semiconductor device or a crystal, comprising:

a crystal forming step of forming a semiconductor layer and an insulating film on a base substrate in this order or in an order reverse to this order;

a bonding step of bonding a support substrate to a surface remote from the base substrate; and

a peeling step of peeling off the base substrate, wherein all the base substrate, the semiconductor layer, and the insulating film have a corundum crystal structure.

26. The method of claim 25, wherein

the support substrate is one of a SiC substrate, a Si substrate, a metal substrate, a ceramic substrate, and a glass substrate.

27. The method of claim 25, wherein

the support substrate is bonded, via a joining layer, to a surface remote from the base substrate.

28. The method of claim 27, wherein the joining layer is formed from a silicon oxide film.