OXIDE SEMICONDUCTOR, THIN FILM TRANSISTOR, AND DISPLAY DEVICE

• US 20100102312A1
• Filed: 10/19/2009
• Published: 04/29/2010
• Est. Priority Date: 10/24/2008
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: ITO, Shunichi, HOSOBA, Miyuki, YAMAZAKI, Shunpei, SASAKI, Toshinari, SAKATA, Junichiro
• Granted Patent: US 9,136,389 B2
• Time in Patent Office: Days
• US Class Current: 257/43
• 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 29/45 Ohmic electrodes
• CPC Class Codes: H01L 29/78618 characterised by the drain or the source properties, e.g. the doping structure, the composition, the sectional shape or the contact structure silicide contacts, electrodes in general H01L29/458
• CPC Class Codes: H01L 29/7869 having a semiconductor body comprising an oxide semiconductor material, e.g. zinc oxide, copper aluminium oxide, cadmium stannate

Abstract

An object is to control composition and a defect of an oxide semiconductor. Another object is to increase field effect mobility of a thin film transistor and to obtain a sufficient on-off ratio with off current suppressed. The oxide semiconductor is represented by InMO₃(ZnO)_n (M is one or a plurality of elements selected from Ga, Fe, Ni, Mn, Co, and Al, and n is a non-integer number of greater than or equal to 1 and less than 50) and further contains hydrogen. In this case, the concentration of Zn is made to be lower than the concentrations of In and M (M is one or a plurality of elements selected from Ga, Fe, Ni, Mn, Co, and Al). In addition, the oxide semiconductor has an amorphous structure. Here, n is preferably a non-integer number of greater than or equal to 50, more preferably less than 10.

Claims

1. An oxide semiconductor comprising:

In, Ga, and Zn as components,

wherein the oxide semiconductor further contains hydrogen.

2. The oxide semiconductor according to claim 1, wherein In and Ga are each contained at a concentration of greater than or equal to 15.0 atomic % and less than or equal to 20.0 atomic %, and Zn is contained at a concentration of greater than or equal to 5.0 atomic % and less than or equal to 10.0 atomic %.

7. The oxide semiconductor according to claim 1, wherein the oxide semiconductor has an amorphous structure.

3. An oxide semiconductor,

wherein the oxide semiconductor is represented by InMO₃(ZnO)_n (M is one or a plurality of elements selected from a group consisting of Ga, Fe, Ni, Mn, Co, and Al, and n is a non-integer number of greater than or equal to 1 and less than 50) and further contains hydrogen.

4. The oxide semiconductor according to claim 3, wherein a concentration of Zn is lower than concentrations of In and M (M is one or more elements selected from a group consisting of Ga, Fe, Ni, Mn, Co, and Al).

8. The oxide semiconductor according to claim 3, wherein the oxide semiconductor has an amorphous structure.

5. An oxide semiconductor,

wherein the oxide semiconductor is an oxide containing In, Ga, and Zn, where the ratio of In atoms to Ga and Zn atoms is 1:

1;

x (x<

10), and further contains hydrogen.

9. The oxide semiconductor according to claim 5, wherein the oxide semiconductor has an amorphous structure.

6. An oxide semiconductor,

wherein the oxide semiconductor is represented by InMO₃(ZnO)_m (M is one or a plurality of elements selected from a group consisting of Ga, Fe, Ni, Mn, Co, and Al, and m is an integer number of greater than or equal to 1 and less than 50) and contains hydrogen.

10. The oxide semiconductor according to claim 6, wherein the oxide semiconductor has an amorphous structure.

11. A thin film transistor comprising:

an oxide semiconductor as a channel formation region,

the oxide semiconductor comprising;

In, Ga, and Zn as components; and

hydrogen.

12. The thin film transistor according to claim 11, wherein In and Ga are each contained at a concentration of greater than or equal to 15.0 atomic % and less than or equal to 20.0 atomic %, and Zn is contained at a concentration of greater than or equal to 5.0 atomic % and less than or equal to 10.0 atomic %.

17. The thin film transistor according to claim 11, wherein the oxide semiconductor has an amorphous structure.

21. The thin film transistor according to claim 11, wherein an oxide insulating layer containing hydrogen is provided in contact with the oxide semiconductor.

25. The thin film transistor according to claim 11, wherein an oxide insulating layer is provided each of upper and lower sides of the oxide semiconductor.

29. The thin film transistor according to claim 11, wherein a nitride insulating layer is provided over the oxide semiconductor.

33. The thin film transistor according to claim 11, wherein a nitride insulating layer is provided under the oxide semiconductor.

37. The thin film transistor according to claim 11, wherein the thin film transistor is provided in at least one pixel.

41. The thin film transistor according to claim 37, wherein the thin film transistor is provided in a driver circuit for controlling a signal to be transmitted to the thin film transistor provided in the pixel.

13. A thin film transistor comprising:

an oxide semiconductor as a channel formation region,

wherein the oxide semiconductor is an oxide semiconductor which is represented by InMO₃(ZnO)_n (M is one or a plurality of elements selected from a group consisting of Ga, Fe, Ni, Mn, Co, and Al, and n is a non-integer number of greater than or equal to 1 and less than

     50) and further contains hydrogen.

14. The thin film transistor according to claim 13, wherein a concentration of Zn is lower than concentrations of In and M (M is one ore more elements selected from a group consisting of Ga, Fe, Ni, Mn, Co, and Al).

18. The thin film transistor according to claim 13, wherein the oxide semiconductor has an amorphous structure.

22. The thin film transistor according to claim 13, wherein an oxide insulating layer containing hydrogen is provided in contact with the oxide semiconductor.

26. The thin film transistor according to claim 13, wherein an oxide insulating layer is provided on each of upper and lower sides of the oxide semiconductor.

30. The thin film transistor according to claim 13, wherein a nitride insulating layer is provided over the oxide semiconductor.

34. The thin film transistor according to claim 13, wherein a nitride insulating layer is provided under the oxide semiconductor.

38. The thin film transistor according to claim 13, wherein the thin film transistor is provided in at least one pixel.

42. The thin film transistor according to claim 38, wherein the thin film transistor is provided in a driver circuit for controlling a signal to be transmitted to the thin film transistor provided in the pixel.

15. A thin film transistor comprising:

an oxide semiconductor as a channel formation region,

wherein the oxide semiconductor is an oxide containing In, Ga, and Zn, where the ratio of In atoms to Ga and Zn atoms is 1;

1;

x (x<

10), and further contains hydrogen.

19. The thin film transistor according to claim 15, wherein the oxide semiconductor has an amorphous structure.

23. The thin film transistor according to claim 15, wherein an oxide insulating layer containing hydrogen is provided in contact with the oxide semiconductor.

27. The thin film transistor according to claim 15, wherein an oxide insulating layer is provided on each of upper and lower sides of the oxide semiconductor.

31. The thin film transistor according to claim 15, wherein a nitride insulating layer is provided over the oxide semiconductor.

35. The thin film transistor according to claim 15, wherein a nitride insulating layer is provided under the oxide semiconductor.

39. The thin film transistor according to claim 15, wherein the thin film transistor is provided in at least one pixel.

43. The thin film transistor according to claim 39, wherein the thin film transistor is provided in a driver circuit for controlling a signal to be transmitted to the thin film transistor provided in the pixel.

16. A thin film transistor comprising:

an oxide semiconductor as a channel formation region,

wherein the oxide semiconductor is represented by InMO₃(ZnO)_m (M is one or a plurality of elements selected from a group consisting of Ga, Fe, Ni, Mn, Co, and Al, and m is a non-integer number of greater than or equal to 1 and less than

     50) and further contains hydrogen.

20. The thin film transistor according to claim 16, wherein the oxide semiconductor has an amorphous structure.

24. The thin film transistor according to claim 16, wherein an oxide insulating layer containing hydrogen is provided in contact with the oxide semiconductor.

28. The thin film transistor according to claim 16, wherein an oxide insulating layer is provided on each of upper and lower sides of the oxide semiconductor.

32. The thin film transistor according to claim 16, wherein a nitride insulating layer is provided over the oxide semiconductor.

36. The thin film transistor according to claim 16, wherein a nitride insulating layer is provided under the oxide semiconductor.

40. The thin film transistor according to claim 16, wherein the thin film transistor is provided in at least one pixel.

44. The thin film transistor according to claim 40, wherein the thin film transistor is provided in a driver circuit for controlling a signal to be transmitted to the thin film transistor provided in the pixel.