Transistor and semiconductor device

• US 6,727,522 B1
• Filed: 06/06/2001
• Issued: 04/27/2004
• Est. Priority Date: 11/17/1998
• Status: Expired due to Fees

• Current Assignee: Japan Science And Technology Agency
• Original Assignee: Japan Science And Technology Corpration (Japan Science And Technology Agency)
• Inventors: Kawasaki, Masashi, Ohno, Hideo
• Primary Examiner(s): Eckert, George
• Assistant Examiner(s): Díaz, José R.
• Application Number:
  US09/850,732
• Time in Patent Office: 1,056 Days
• Field of Search: 257/94, 257/96, 257/97, 257/98, 257/103, 257/295, 257/300, 257/310, 257/407, 257/410, 257/411, 257/412, 257/613, 257/614, 257/615, 257/616, 257/102, 438/478, 438/608, 438/609
• US Class Current: 257/103
• CPC Class Codes: H01L 27/15 including semiconductor components having potential barriers, specially adapted for light emission
• CPC Class Codes: H01L 29/22 including, apart from doping materials or other impurities, only AIIBVI compounds
• CPC Class Codes: H01L 29/45 Ohmic electrodes
• CPC Class Codes: H01L 29/4908 for thin film semiconductor, e.g. gate of TFT
• CPC Class Codes: H01L 29/517 the insulating material comprising a metallic compound, e.g. metal oxide, metal silicate H01L29/518 takes precedence
• CPC Class Codes: H01L 29/7317 Bipolar thin film transistors
• CPC Class Codes: H01L 29/78 with field effect produced by an insulated gate H01L29/7725, H01L29/775, H01L29/778 take precedence
• 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
• CPC Class Codes: H01L 33/28 containing only elements of Group II and Group VI of the Periodic Table
• CPC Class Codes: H01S 5/0261 Non-optical elements, e.g. laser driver components, heaters H01S5/0265 takes precedence

Abstract

A transistor is provided, which is entirely and partially transparent by the use of a transparent channel layer made of zinc oxide or the like. A channel layer 11 formed of a transparent semiconductor such as zinc oxide ZnO. A transparent electrode is used for all of a source 12, a drain 13 and a gate 14, or a part of them. As the transparent electrode, a transparent conductive material such as conductive ZnO doped with, for example, group III elements is used. As a gate insulating layer 15, a transparent insulative material such as insulative ZnO doped with elements capable of taking a valence of one as a valence number or group V elements is used. If a substrate 16 must be transparent, for example, glass, sapphire, plastic or the like can be used as a transparent material.

Claims

1. A transistor comprising:

a transparent channel layer using any one of zinc oxide ZnO, zinc magnesium oxide Mg_xZn<sub>1−

x</sub>O, zinc cadmium oxide Cd_xZn<sub>1−

x</sub>O and cadmium oxide CdO; and

a source, a drain and a gate each of which is in contact with said transparent channel layers and said gate is at least partially between said source and said drain;

contacts to at least one of said source, said drain, and said gate, in which said contacts to at least one of said source, said drain, and said gate include a transparent conductive material.

2. The transistor according to claim 1, the transistor further comprising:

a gate insulating layer using a transparent insulating material comprising insulative ZnO doped with elements capable of taking a valence of 1 as a valence number or doped with group V element, a transparent insulating oxide, or a transparent insulator between said transparent channel layer and said gate.

3. The transistor according to claim 2, the transistor further comprising;

a transparent insulating substrate on which said transparent channel layer is formed.

4. A semiconductor device, comprising:

the transistor according to claim 2; and

a light emission portion formed of a region continuous to said drain or said source of said transistor or a region of another semiconductor connected to said drain or said source, and a semiconductor layer jointed to said region.

5. A semiconductor device, comprising:

the transistor according to claim 2; and

a capacitor formed by a region continuous to said drain or said source of said transistor or a region of another semiconductor or a conductor connected to said drain and said source, said gate insulating layer or another insulating layer on said source, said gate insulating layer or another insulating layer on said region, and a semiconductor layer or a conductive layer on said gate insulating layer or said another insulating layer.

6. A semiconductor device, wherein the transistor according to claim 2 is stacked in plural with an insulating layer therebetween, the insulating layer using a transparent insulating material comprising insulative ZnO doped with elements capable of taking a valence of one as a valence number or group V elements, a transparent insulating oxide, or a transparent insulator.

7. A semiconductor device, comprising:

a plurality of transistors according to claim 2, wherein a transparent conductive material comprising conductive ZnO doped or undoped with group III elements, group VII elements, group I elements and group V elements, a transparent conductor comprising at least one of In₂O₃, SnO₂ and (In—

Sn)O_x, or a untransparent electrode material is used for all of wiring or a part of the wiring between said transistors.

8. A semiconductor device, comprising:

the transistor according to claim 2; and

an inductor made of a transparent conductive material comprising conductive ZnO doped or undoped with group III elements, group VII elements, group I elements and group V elements, or a transparent conductor comprising at least one of In₂O₃, SnO₂ and (In—

Sn)O_x.

9. The transistor according to claim 1, the transistor further comprising:

a gate insulating layer using a high dielectric transparent insulating material comprising at least one of Zn<sub>1−

x</sub>Li_xO and Zn<sub>1−

x</sub>(Li_yMg<sub>x−

y</sub>) between said transparent channel layer and said gate,

where said gate insulating layer has a memory function.

10. The transistor according to claim 9, the transistor further comprising;

a transparent insulating substrate on which said transparent channel layer is formed.

11. A semiconductor device, comprising:

the transistor according to claim 9; and

a light emission portion formed of a region continuous to said drain or said source of said transistor or a region of another semiconductor connected to said drain or said source, and a semiconductor layer jointed to said region.

12. A semiconductor device, comprising:

the transistor according to claim 9; and

a capacitor formed by a region continuous to said drain or said source of said transistor or a region of another semiconductor or a conductor connected said drain and said source, said gate insulating layer or another insulating layer on said source, said gate insulating layer or another insulating layer on said region, and a semiconductor layer or a conductive layer on said gate insulating layer or said another insulating layer.

13. A semiconductor device, wherein the transistor according to claim 9 is stacked in plural with an insulating layer therebetween, the insulating layer using a transparent insulating material comprising insulative ZnO doped with elements capable of taking a valence of one as a valence number or group V elements, a transparent insulating oxide, or a transparent insulator.

14. A semiconductor device, comprising:

a plurality of transistors according to claim 9, wherein a transparent conductive material comprising conductive ZnO doped or undoped with group III elements, group VII elements, group I elements and group V elements, a transparent conductor comprising at least one of In₂O₃, SnO₂ and (In—

Sn)O_x, or a untransparent electrode material is used for all of wiring or a part of the wiring between said transistors.

15. A semiconductor device, comprising:

the transistor according to claim 9; and

an inductor made of a transparent conductive material comprising conductive ZnO doped or undoped with group III elements, group VII elements, group I elements and group V elements, or a transparent conductor comprising at least one of In₂O₃, SnO₂, and (In—

Sn)O_x.

16. The transistor according to claim 1, the transistor further comprising;

a transparent insulating substrate on which said transparent channel layer is formed.

17. A semiconductor device, comprising:

the transistor according to claim 16; and

a light emission portion formed of a region continuous to said drain or said source of said transistor or a region of another semiconductor connected to said drain or said source, and a semiconductor layer jointed to said region.

18. A semiconductor device, comprising:

the transistor according to claim 16; and

a capacitor formed by a region continuous to said drain or said source of said transistor or a region of another semiconductor or a conductor connected said drain and said source, said gate insulating layer or another insulating layer on said source, said gate insulating layer or another insulating layer on said region, and a semiconductor layer or a conductive layer on said gate insulating layer or said another insulating layer.

19. A semiconductor device, wherein the transistor according to claim 16, is stacked in plural with an insulating layer therebetween, the insulating layer using a transparent insulating material comprising insulative ZnO doped with elements capable of taking a valence of one as a valence number or group V elements, a transparent insulating oxide, or a transparent insulator.

20. A semiconductor device, comprising:

a plurality of transistors according to claim 16, wherein a transparent conductive material comprising conductive ZnO doped or undoped with group III elements, group VII elements, group I elements and group V elements, a transparent conductor comprising at least one of In₂O₃, SnO₂ and (In—

Sn)O_x, or a untransparent electrode material is used for all of wiring or a part of the wiring between said transistors.

21. A semiconductor device, comprising:

the transistor according to claim 16; and

an inductor made of a transparent conductive material comprising conductive ZnO doped or undoped with group III elements, group VII elements, group I elements and group V elements, or a transparent conductor comprising at least one of In₂O₃, SnO₂, and (In—

Sn)O_x.

22. A semiconductor device, comprising:

the transistor according to claim 1; and

a light emission portion formed of a region continuous to said drain or said source of said transistor or a region of another semiconductor connected to said drain or said source, and a semiconductor layer jointed to said region.

23. A semiconductor device, wherein a plurality of the semiconductor devices according to claim 22, are arranged in a matrix shape, and a capacitor or a light emission portion is driven by each transistor.

24. A semiconductor device, comprising:

the transistor according to claim 1; and

a capacitor formed by a region continuous to said drain or said source of said transistor or a region of another semiconductor or a conductor connected said drain and said source, said gate insulating layer or another insulating layer on said source, said gate insulating layer or another insulating layer on said region, and a semiconductor layer or a conductive layer on said gate insulating layer or said another insulating layer.

25. A semiconductor device, wherein a plurality of the semiconductor devices according to claim 24, are arranged in a matrix shape, and a capacitor or a light emission portion is driven by each transistor.

26. A semiconductor device, wherein the transistor according to claim 1 is stacked in plural with an insulating layer therebetween, the insulating layer using a transparent insulating material comprising insulative ZnO doped with elements capable of taking a valence of one as a valence number or group V elements, a transparent insulating oxide, or a transparent insulator.

27. A semiconductor device, comprising:

a plurality of transistors according to claim 1, wherein a transparent conductive material comprising conductive ZnO doped or undoped with group III elements, group VII elements, group I elements and group V elements, a transparent conductor such as In₂O₃, SnO₂ and (In—

Sn)O_x, or a untransparent electrode material is used for all of wiring or a part of the wiring between said transistors.

28. A semiconductor device, comprising:

the transistor according to claim 1; and

an inductor made of a transparent conductive material comprising conductive ZnO doped or undoped with group III elements, group VII elements, group I elements and group V elements, or a transparent conductor such as In₂O₃, SnO₂ and (In—

Sn)O_x.

29. The transistor of claim 1 wherein said transparent conductive material includes at least conductive ZnO.

30. The transistor of claim 29 wherein said conductive ZnO is doped with at least one of group III elements, group VII elements, group I elements and group V elements.

31. The transistor of claim 1 wherein said transparent conductive material includes at least one of In₂O₃, SnO₂ and (In—

Sn)O_x.

32. The transistor of claim 1 wherein said transparent channel layer comprises zinc magnesium oxide with a substantial amount of magnesium.

33. The transistor of claim 1 wherein said transparent channel layer comprises zinc cadmium oxide with a substantial amount of cadmium.

34. The transistor of claim 1 wherein said transparent channel layer comprises cadmium oxide.

35. A transistor comprising:

a transparent channel layer including any one of, zinc magnesium oxide Mg_xZn<sub>1−

x</sub>O, zinc cadmium oxide Cd_xZn<sub>1−

x</sub>O and cadmium oxide CdO; and

a source, a drain and a gate each of which is in contact with said transparent channel layer.

36. The transistor of claim 35 further comprising at least one electrode, said at least one electrode contacts at least one of said source, said drain, and said gate, wherein said at least one electrode includes a transparent conductive material.

37. The transistor of claim 36 wherein said transparent conductive material includes at least conductive ZnO.

38. The transistor of claim 37 wherein said conductive ZnO is doped with any at least one of group III elements, group VII elements, group I elements and group V elements.

39. The transistor of claim 36 wherein said transparent conductive material includes at least one of In₂O₃, SnO₂ and (In—

Sn)O_x.

40. The method of claim 38 wherein said transparent channel layer comprises zinc magnesium oxide with a substantial amount of magnesium.

41. The method of claim 38 wherein said transparent channel layer comprises zinc cadmium oxide with a substantial amount of cadmium.

42. The method of claim 38 wherein said transparent channel layer comprises cadmium oxide.

43. A method of forming a transistor comprising:

depositing a transparent channel layer using any one of zinc oxide ZnO, zinc magnesium oxide Mg_xZn<sub>1−

x</sub>O, zinc cadmium oxide Cd_xZn<sub>1−

x</sub>O and cadmium oxide CdO; and

depositing contacts to a source region in said channel layer, a drain region in said channel layer, and a gate region in said channel layer, wherein at least one of said contacts includes a transparent conductive material.

44. The method of claim 43 wherein said transparent channel layer is deposited prior to depositing said contacts.