STACKED OXIDE MATERIAL, SEMICONDUCTOR DEVICE, AND METHOD FOR MANUFACTURING THE SEMICONDUCTOR DEVICE

• US 20110127521A1
• Filed: 11/22/2010
• Published: 06/02/2011
• 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
• Granted Patent: US 8,748,215 B2
• Time in Patent Office: Days
• US Class Current: 257/43
• CPC Class Codes: H01L 21/0242 Crystalline insulating materials
• CPC Class Codes: H01L 21/02422 Non-crystalline insulating materials, e.g. glass, polymers
• 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 21/02488 Insulating materials
• CPC Class Codes: H01L 21/02502 consisting of two layers
• 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 21/02592 amorphous
• CPC Class Codes: H01L 21/02631 Physical deposition at reduced pressure, e.g. MBE, sputtering, evaporation
• CPC Class Codes: H01L 21/02667 Crystallisation or recrystallisation of non-monocrystalline semiconductor materials, e.g. regrowth
• CPC Class Codes: H01L 27/12 the substrate being other than a semiconductor body, e.g. an insulating body
• CPC Class Codes: H01L 27/1214 comprising a plurality of TFTs formed on a non-semiconducting substrate, e.g. driving circuits for AMLCDs
• 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 29/24 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
• 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 29/78696 characterised by the structure of the channel, e.g. multichannel, transverse or longitudinal shape, length or width, doping structure, or the overlap or alignment between the channel and the gate, the source or the drain, or the contacting structure of the channel H01L29/78612 takes precedence; transistors having a drain offset region or a lightly doped drain [LDD] H01L29/78621
• CPC Class Codes: Y10T 156/10 Methods of surface bonding and/or assembly therefor
• CPC Class Codes: Y10T 428/24174 : including sheet or component perpendicular to plane of web or sheet

Abstract

One embodiment is a method for manufacturing a stacked oxide material, including the steps of forming an oxide component over a base component; forming a first oxide crystal component which grows from a surface toward an inside of the oxide component by heat treatment, and leaving an amorphous component just above a surface of the base component; and stacking a second oxide crystal component over the first oxide crystal component. In particular, the first oxide crystal component and the second oxide crystal component have common c-axes. Same-axis (axial) growth in the case of homo-crystal growth or hetero-crystal growth is caused.

Claims

1. A method for manufacturing a stacked oxide material, comprising the steps of:

forming an oxide component over a base component;

forming a first oxide crystal component which grows from an upper surface toward an inside of the oxide component by heat treatment, and leaving an amorphous component just above a surface of the base component; and

stacking a second oxide crystal component over the first oxide crystal component.

4. The method for manufacturing a stacked oxide material, according to claim 1, wherein the heat treatment is performed in a nitrogen atmosphere, an oxygen atmosphere, or a dry air atmosphere at a temperature higher than or equal to 450°

C. and lower than or equal to 850°

C.

7. The method for manufacturing a stacked oxide material, according to claim 1, wherein each of the first oxide crystal component and the second oxide crystal component is c-axis-aligned perpendicularly to a surface of the first oxide crystal component.

10. The method for manufacturing a stacked oxide material, according to claim 1, wherein the oxide component is formed by a sputtering method.

13. The method for manufacturing a stacked oxide material, according to claim 1, wherein the first oxide crystal component and the second oxide crystal component are non-single crystals.

16. The method for manufacturing a stacked oxide material, according to claim 1, wherein the second oxide crystal component is obtained by causing crystal growth in a state where heating is performed at a temperature during deposition of higher than or equal to 200°

C. and lower than or equal to 600°

C.

19. The method for manufacturing a stacked oxide material, according to claim 1,

wherein the second oxide crystal component is deposited by a sputtering method,

wherein heat treatment is performed after or at the same time as the deposition of the second oxide crystal component,

wherein a metal oxide target for the deposition has a composition ratio of In:

Ga;

Zn=1;

x;

y, and

wherein x is greater than or equal to 0 and less than or equal to 2, and y is greater than or equal to 1 and less than or equal to 5.

20. The method for manufacturing a stacked oxide material, according claim 19, wherein x is 1 and y is 1.

21. The method for manufacturing a stacked oxide material, according claim 19, wherein x is 0 and y is 1.

28. The method for manufacturing a stacked oxide material, according to claim 1, wherein the first oxide crystal component has high purity and has an intrinsic conductivity type.

31. The method for manufacturing a stacked oxide material, according to claim 1, wherein the second oxide crystal component has high purity and has an intrinsic conductivity type.

34. The method for manufacturing a stacked oxide material, according to claim 1, wherein a carrier concentration of the stacked oxide material is less than 1.0×

10¹² cm<sup>−

3</sup>.

37. The method for manufacturing a stacked oxide material, according to claim 1, wherein a carrier concentration of the stacked oxide material is less than 1.45×

10¹⁰ cm<sup>−

3</sup>.

40. The method for manufacturing a stacked oxide material, according to claim 1, wherein a bottom interface of the first oxide crystal component in which crystals are aligned is provided to be spaced from the surface of the base component.

2. A method for manufacturing a stacked oxide material, comprising the steps of:

forming an oxide component over a base component;

forming a first oxide crystal component which grows from an upper surface toward an inside of the oxide component by heat treatment and leaving an amorphous component just above a surface of the base component; and

stacking a second oxide crystal component which is formed using the same material as the first oxide crystal component and caused homo-crystal growth over the first oxide crystal component.

5. The method for manufacturing a stacked oxide material, according to claim 2, wherein the heat treatment is performed in a nitrogen atmosphere, an oxygen atmosphere, or a dry air atmosphere at a temperature higher than or equal to 450°

C. and lower than or equal to 850°

C.

8. The method for manufacturing a stacked oxide material, according to claim 2, wherein each of the first oxide crystal component and the second oxide crystal component is c-axis-aligned perpendicularly to a surface of the first oxide crystal component.

11. The method for manufacturing a stacked oxide material, according to claim 2, wherein the oxide component is formed by a sputtering method.

14. The method for manufacturing a stacked oxide material, according to claim 2, wherein the first oxide crystal component and the second oxide crystal component are non-single crystals.

17. The method for manufacturing a stacked oxide material, according to claim 2, wherein the second oxide crystal component is obtained by causing crystal growth in a state where heating is performed at a temperature during deposition of higher than or equal to 200°

C. and lower than or equal to 600°

C.

22. The method for manufacturing a stacked oxide material, according to claim 2,

wherein the second oxide crystal component is deposited by a sputtering method,

wherein heat treatment is performed after or at the same time as the deposition of the second oxide crystal component,

wherein a metal oxide target for the deposition has a composition ratio of In:

Ga;

Zn=1;

x;

y, and

wherein x is greater than or equal to 0 and less than or equal to 2, and y is greater than or equal to 1 and less than or equal to 5.

23. The method for manufacturing a stacked oxide material, according claim 22, wherein x is 1 and y is 1.

24. The method for manufacturing a stacked oxide material, according claim 22, wherein x is 0 and y is 1.

29. The method for manufacturing a stacked oxide material, according to claim 2, wherein the first oxide crystal component has high purity and has an intrinsic conductivity type.

32. The method for manufacturing a stacked oxide material, according to claim 2, wherein the second oxide crystal component has high purity and has an intrinsic conductivity type.

35. The method for manufacturing a stacked oxide material, according to claim 2, wherein a carrier concentration of the stacked oxide material is less than 1.0×

10¹² cm<sup>−

3</sup>.

38. The method for manufacturing a stacked oxide material, according to claim 2, wherein a carrier concentration of the stacked oxide material is less than 1.45×

10¹⁰ cm<sup>−

3</sup>.

41. The method for manufacturing a stacked oxide material, according to claim 2, wherein a bottom interface of the first oxide crystal component in which crystals are aligned is provided to be spaced from the surface of the base component.

3. A method for manufacturing a stacked oxide material, comprising the steps of:

forming an oxide component over a base component;

forming a first oxide crystal component which grows from an upper surface toward an inside of the oxide component by heat treatment and leaving an amorphous component just above a surface of the base component; and

stacking a second oxide crystal component which is formed using a different material from the first oxide crystal component and caused hetero-crystal growth over the first oxide crystal component.

6. The method for manufacturing a stacked oxide material, according to claim 3, wherein the heat treatment is performed in a nitrogen atmosphere, an oxygen atmosphere, or a dry air atmosphere at a temperature higher than or equal to 450°

C. and lower than or equal to 850°

C.

9. The method for manufacturing a stacked oxide material, according to claim 3, wherein each of the first oxide crystal component and the second oxide crystal component is c-axis-aligned perpendicularly to a surface of the first oxide crystal component.

12. The method for manufacturing a stacked oxide material, according to claim 3, wherein the oxide component is formed by a sputtering method.

15. The method for manufacturing a stacked oxide material, according to claim 3, wherein the first oxide crystal component and the second oxide crystal component are non-single crystals.

18. The method for manufacturing a stacked oxide material, according to claim 3, wherein the second oxide crystal component is obtained by causing crystal growth in a state where heating is performed at a temperature during deposition of higher than or equal to 200°

C. and lower than or equal to 600°

C.

25. The method for manufacturing a stacked oxide material, according to claim 3,

wherein the second oxide crystal component is deposited by a sputtering method,

wherein heat treatment is performed after or at the same time as the deposition of the second oxide crystal component,

wherein a metal oxide target for the deposition has a composition ratio of In:

Ga;

Zn=1;

x;

y, and

wherein x is greater than or equal to 0 and less than or equal to 2, and y is greater than or equal to 1 and less than or equal to 5.

26. The method for manufacturing a stacked oxide material, according claim 25, wherein x is 1 and y is 1.

27. The method for manufacturing a stacked oxide material, according claim 25, wherein x is 0 and y is 1.

30. The method for manufacturing a stacked oxide material, according to claim 3, wherein the first oxide crystal component has high purity and has an intrinsic conductivity type.

33. The method for manufacturing a stacked oxide material, according to claim 3, wherein the second oxide crystal component has high purity and has an intrinsic conductivity type.

36. The method for manufacturing a stacked oxide material, according to claim 3, wherein a carrier concentration of the stacked oxide material is less than 1.0×

10¹² cm<sup>−

3</sup>.

39. The method for manufacturing a stacked oxide material, according to claim 3, wherein a carrier concentration of the stacked oxide material is less than 1.45×

10¹⁰ cm<sup>−

3</sup>.

42. The method for manufacturing a stacked oxide material, according to claim 3, wherein a bottom interface of the first oxide crystal component in which crystals are aligned is provided to be spaced from the surface of the base component.

43. A stacked oxide material comprising;

a first oxide crystal component whose crystal growth proceeded from a surface toward an inside of the first oxide crystal component, over a base component; and

a second oxide crystal component over the first oxide crystal component.

44. The stacked oxide material according to claim 43, wherein the first oxide crystal component whose crystal growth proceeded from the surface toward the inside is c-axis-aligned perpendicularly to the surface.

45. The stacked oxide material according to claim 43, wherein a bottom interface whose crystal is aligned of the first oxide crystal component is provided to be spaced from the base component.

46. The stacked oxide material according to claim 43, wherein the base component includes an insulating surface, an oxide surface, a nitride surface, or a metal surface.

47. The stacked oxide material according to claim 43, wherein an oxide component including an amorphous region is positioned between the base component and the first oxide crystal component.

48. A stacked oxide material comprising:

a first oxide crystal component; and

a second oxide crystal component over and in contact with the first oxide crystal component,

wherein a crystal structure of the second oxide crystal component is the same as the first oxide crystal component, and

wherein at least part of the second oxide crystal component grows above a surface of the first oxide crystal component.

49. The stacked oxide material according to claim 48, wherein the first oxide crystal component whose crystal growth proceeded from a surface to an inside is c-axis-aligned perpendicularly to the surface.

50. The stacked oxide material according to claim 48, wherein the first oxide crystal component and the second oxide crystal component are formed using materials including the same components.

51. The stacked oxide material according to claim 48, wherein the first oxide crystal component and the second oxide crystal component have the same electron affinity.

52. The stacked oxide material according to claim 48, wherein the first oxide crystal component and the second oxide crystal component are formed using different materials.

53. A method for manufacturing a semiconductor device, comprising the steps of:

forming a gate electrode layer including a flat surface over a surface of a base;

forming a gate insulating layer over the gate electrode layer;

forming a first oxide semiconductor layer over the gate insulating layer;

causing crystal growth which proceeds from an upper surface toward an inside of the first oxide semiconductor layer by first heat treatment to form a first non-single crystalline layer;

forming a second oxide semiconductor layer over the first non-single crystalline layer;

causing crystal growth which proceeds from the first non-single crystalline layer toward an upper surface of the second oxide semiconductor layer over the first non-single crystalline layer by second heat treatment to form a second non-single crystalline layer; and

forming a source electrode layer and a drain electrode layer over a stack of the first non-single crystalline layer and the second non-single crystalline layer,

wherein a bottom interface whose crystal is aligned of the first non-single crystalline layer is provided to be spaced from a surface of the gate insulating layer.

54. The method for manufacturing a semiconductor device, according to claim 53,

wherein the first non-single crystalline layer is c-axis-aligned perpendicularly to a surface thereof.

55. The method for manufacturing a semiconductor device, according to claim 53,

wherein the second non-single crystalline layer is c-axis-aligned perpendicularly to a surface thereof.

56. The method for manufacturing a semiconductor device, according to claim 53, wherein the second oxide semiconductor layer has a larger thickness than the first oxide semiconductor layer.

57. A semiconductor device comprising:

a gate electrode layer including a flat surface over a surface of a base;

a gate insulating layer over the gate electrode layer;

a metal oxide layer including an amorphous region over the gate insulating layer;

a first non-single crystalline layer which is c-axis-aligned perpendicularly to a surface, over the metal oxide layer including the amorphous region;

a second non-single crystalline layer which is on and in contact with the first non-single crystalline layer and c-axis-aligned perpendicularly to the surface thereof; and

a source electrode and a drain electrode over a stack of the first non-single crystalline layer and the second non-single crystalline layer,

wherein the first non-single crystalline layer and the second non-single crystalline layer are metal oxide layers.

58. The semiconductor device according to claim 57, wherein the second non-single crystalline layer has a larger thickness than the first non-single crystalline layer.

59. The semiconductor device according to claim 57, wherein the first non-single crystalline layer and the second non-single crystalline layer have a same electron affinity.

60. The semiconductor device according to claim 57, wherein the first non-single crystalline layer and the second non-single crystalline layer are formed using different materials.

61. The semiconductor device according to claim 57, wherein a difference in height at a region in the surface of the second non-single crystalline layer which overlaps with the gate electrode layer is less than or equal to 1 nm.

62. The semiconductor device according to claim 57, wherein a difference in height at a region in the surface of the second non-single crystalline layer which overlaps with the gate electrode layer is less than or equal to 0.2 nm.