SEMICONDUCTOR DEVICE

• US 20130119373A1
• Filed: 10/18/2012
• Published: 05/16/2013
• Est. Priority Date: 11/11/2011
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: YAMAZAKI, Shunpei
• Granted Patent: US 9,082,861 B2
• Time in Patent Office: Days
• US Class Current: 257/43
• 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

A highly reliable semiconductor device is provided. Over an oxide semiconductor layer in which a channel is formed, an insulating layer including the oxide semiconductor material having a higher insulating property than an oxide semiconductor layer is formed. A material which contains an element M and is represented by a chemical formula InMZnO_X (X>0) or an oxide material which contains an element M₁ and an element M₂ and is represented by a chemical formula InM_1XM_2(1−X)ZnO (0<X<1+α where α is less than 0.3 and (1−X)>0) is used as the oxide semiconductor material having a high insulating property. Ti, Zr, Hf, Ge, Ce, or Y is used as the element M and the element M₂, for example. Ga is used as the element M₁, for example.

Claims

1. A semiconductor device comprising:

a gate electrode;

a gate insulating layer;

an oxide semiconductor layer; and

a protective layer,

wherein the oxide semiconductor layer overlaps with the gate electrode with the gate insulating layer interposed therebetween,

wherein the protective layer overlaps with the gate insulating layer with the oxide semiconductor layer interposed therebetween,

wherein the protective layer includes an oxide material containing In, an element M, and Zn, and

wherein the element M is a Group 3A element, a Group 4A element, or a Group 4B element.

2. The semiconductor device according to claim 1, wherein the protective layer includes a material which contains the element M and is represented by a chemical formula InMZnO_X (X>

0).

3. The semiconductor device according to claim 1, wherein the element M is Ti, Zr, Hf, Ge, Ce, or Y.

4. The semiconductor device according to claim 1, wherein the protective layer includes an oxide semiconductor having a higher insulating property than the oxide semiconductor layer.

5. The semiconductor device according to claim 1, wherein the semiconductor device is one selected from the group consisting of a table having a display portion, a television set, a computer, and a tablet.

6. A semiconductor device comprising:

a gate electrode;

a gate insulating layer;

an oxide semiconductor layer; and

a protective layer,

wherein the oxide semiconductor layer overlaps with the gate electrode with the gate insulating layer interposed therebetween,

wherein the protective layer overlaps with the gate insulating layer with the oxide semiconductor layer interposed therebetween,

wherein the protective layer includes an oxide material containing In, an element M₁, an element M₂, and Zn,

wherein the element M₁ is a Group 3B element, and

wherein the element M₂ is a Group 3A element, a Group 4A element, or a Group 4B element.

7. The semiconductor device according to claim 6, wherein the protective layer includes a material which contains the element M₁ and the element M₂ and is represented by a chemical formula InM_1XM₂₍₁₋

X)ZnO (0<

X<

1+α

where α

is less than 0.3 and (1−

X)>

0).

8. The semiconductor device according to claim 6, wherein the element M₁ is Ga.

9. The semiconductor device according to claim 6, wherein the element M₂ is Ti, Zr, Hf, Ge, Ce, or Y.

10. The semiconductor device according to claim 6, wherein the protective layer includes an oxide semiconductor having a higher insulating property than the oxide semiconductor layer.

11. The semiconductor device according to claim 6, wherein the semiconductor device is one selected from the group consisting of a table having a display portion, a television set, a computer, and a tablet.