Oxide semiconductor film on amorphous insulating surface

• US 8,698,138 B2
• Filed: 12/13/2012
• Issued: 04/15/2014
• Est. Priority Date: 11/28/2009
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Yamazaki, Shunpei
• Primary Examiner(s): Chambliss, Alonzo
• Application Number:
  US13/713,385
• Publication Number:
  US 20130099234A1
• Time in Patent Office: 488 Days
• Field of Search: None
• US Class Current: 257/43
• CPC Class Codes: H01L 21/02472 Oxides
• CPC Class Codes: H01L 21/02483 Oxide semiconducting materials not being Group 12/16 materials, e.g. ternary compounds
• CPC Class Codes: H01L 21/02554 Oxides
• CPC Class Codes: H01L 21/02565 Oxide semiconducting materials not being Group 12/16 materials, e.g. ternary compounds
• CPC Class Codes: H01L 21/02631 Physical deposition at reduced pressure, e.g. MBE, sputtering, evaporation
• CPC Class Codes: H01L 21/02634 Homoepitaxy
• CPC Class Codes: H01L 21/02667 Crystallisation or recrystallisation of non-monocrystalline semiconductor materials, e.g. regrowth
• CPC Class Codes: H01L 27/1225 with semiconductor materials not belonging to the group IV of the periodic table, e.g. InGaZnO
• CPC Class Codes: H01L 29/045 by their particular orientation of crystalline planes
• CPC Class Codes: H01L 29/247 Amorphous materials
• CPC Class Codes: H01L 29/66666 Vertical transistors H01L29/66712, H01L29/66742 take precedence
• CPC Class Codes: H01L 29/66969 of devices having semiconductor bodies not comprising group 14 or group 13/15 materials comprising selenium or tellurium in uncombined form other than as impurities in semiconductor bodies of other materials, comprising cuprous oxide or cuprous iodide H01L21/02365
• CPC Class Codes: H01L 29/78642 Vertical transistors
• CPC Class Codes: H01L 29/7869 having a semiconductor body comprising an oxide semiconductor material, e.g. zinc oxide, copper aluminium oxide, cadmium stannate
• CPC Class Codes: H01L 29/78693 the semiconducting oxide being amorphous
• CPC Class Codes: H01L 33/305 characterised by the doping materials

Abstract

Objects are to provide a semiconductor device for high power application in which a novel semiconductor material having high productivity is used and to provide a semiconductor device having a novel structure in which a novel semiconductor material is used. The present invention is a vertical transistor and a vertical diode each of which has a stacked body of an oxide semiconductor in which a first oxide semiconductor film having crystallinity and a second oxide semiconductor film having crystallinity are stacked. An impurity serving as an electron donor (donor) which is contained in the stacked body of an oxide semiconductor is removed in a step of crystal growth; therefore, the stacked body of an oxide semiconductor is highly purified and is an intrinsic semiconductor or a substantially intrinsic semiconductor whose carrier density is low. The stacked body of an oxide semiconductor has a wider band gap than a silicon semiconductor.

Claims

1. An oxide semiconductor film on an amorphous insulating surface, the oxide semiconductor film comprising indium, zinc, a metal element other than indium and zinc, and oxygen,

wherein the oxide semiconductor film is highly purified,

wherein the oxide semiconductor film is intrinsic or substantially intrinsic, and

wherein the oxide semiconductor film includes a plurality of crystalline regions, c-axes of which are substantially perpendicular to a surface of the oxide semiconductor film.

2. The oxide semiconductor film according to claim 1, wherein the metal element is gallium.

3. The oxide semiconductor film according to claim 1,

wherein the oxide semiconductor film is provided on a silicon oxynitride, and

wherein the silicon oxynitride includes the amorphous insulating surface.

4. An oxide semiconductor film on an amorphous insulating surface, the oxide semiconductor film comprising indium, zinc, a metal element other than indium and zinc, and oxygen,

wherein the oxide semiconductor film includes a plurality of crystalline regions, c-axes of which are substantially perpendicular to a surface of the oxide semiconductor film, and

wherein a concentration of iron in the oxide semiconductor film is 1.0×

10¹⁵ atoms/cm³ or lower.

5. The oxide semiconductor film according to claim 4, wherein the metal element is gallium.

6. The oxide semiconductor film according to claim 4,

wherein the oxide semiconductor film is provided on a silicon oxynitride, and

wherein the silicon oxynitride includes the amorphous insulating surface.

7. An oxide semiconductor film on an amorphous insulating surface, the oxide semiconductor film comprising indium, zinc, a metal element other than indium and zinc, and oxygen,

wherein the oxide semiconductor film includes a plurality of crystalline regions, c-axes of which are substantially perpendicular to a surface of the oxide semiconductor film, and

wherein a concentration of nickel in the oxide semiconductor film is 1.0×

10¹⁵ atoms/cm³ or lower.

8. The oxide semiconductor film according to claim 7, wherein the metal element is gallium.

9. The oxide semiconductor film according to claim 7,

wherein the oxide semiconductor film is provided on a silicon oxynitride, and

wherein the silicon oxynitride includes the amorphous insulating surface.

10. An oxide semiconductor film on an amorphous insulating surface, the oxide semiconductor film comprising indium, zinc, a metal element other than indium and zinc, and oxygen,

wherein the oxide semiconductor film includes a plurality of crystalline regions, c-axes of which are substantially perpendicular to a surface of the oxide semiconductor film, and

wherein a concentration of hydrogen in the oxide semiconductor film is 1.0×

10¹⁸ atoms/cm³ or lower.

11. The oxide semiconductor film according to claim 10, wherein the metal element is gallium.

12. The oxide semiconductor film according to claim 10,

wherein the oxide semiconductor film is provided on a silicon oxynitride, and

wherein the silicon oxynitride includes the amorphous insulating surface.

13. An oxide semiconductor film on an amorphous insulating surface, the oxide semiconductor film comprising indium, zinc, a metal element other than indium and zinc, and oxygen,

wherein the oxide semiconductor film includes a plurality of crystalline regions, c-axes of which are substantially perpendicular to a surface of the oxide semiconductor film, and

wherein a concentration of an impurity imparting an n-type conductivity type to the oxide semiconductor film is reduced so that the oxide semiconductor film is intrinsic or substantially intrinsic.

14. The oxide semiconductor film according to claim 13, wherein the metal element is gallium.

15. The oxide semiconductor film according to claim 13,

wherein the oxide semiconductor film is provided on a silicon oxynitride, and

wherein the silicon oxynitride includes the amorphous insulating surface.

16. An oxide semiconductor film on an amorphous insulating surface, the oxide semiconductor film comprising indium, zinc, a metal element other than indium and zinc, and oxygen,

wherein the oxide semiconductor film is highly purified,

wherein the oxide semiconductor film includes a plurality of crystalline regions, c-axes of which are substantially perpendicular to a surface of the oxide semiconductor film, and

wherein a density of state caused due to oxygen defects in the oxide semiconductor film is reduced so that the oxide semiconductor film is intrinsic or substantially intrinsic.

17. The oxide semiconductor film according to claim 16, wherein the metal element is gallium.

18. The oxide semiconductor film according to claim 16,

wherein the oxide semiconductor film is provided on a silicon oxynitride, and

wherein the silicon oxynitride includes the amorphous insulating surface.

19. An oxide semiconductor film on an amorphous insulating surface, the oxide semiconductor film comprising indium, zinc, a metal element other than indium and zinc, and oxygen,

wherein the oxide semiconductor film comprises a first region and a second region over the first region,

wherein the first region comprises an amorphous portion and a plurality of crystals, and

wherein the second region comprises a plurality of crystalline regions, c-axes of which are substantially perpendicular to a surface of the oxide semiconductor film.

20. The oxide semiconductor film according to claim 19, wherein the metal element is gallium.

21. The oxide semiconductor film according to claim 19,

wherein the oxide semiconductor film is provided on a silicon oxynitride, and

wherein the silicon oxynitride includes the amorphous insulating surface.