SEMICONDUCTOR DEVICE AND MANUFACTURING METHOD THEREOF

• US 20130015438A1
• Filed: 09/14/2012
• Published: 01/17/2013
• Est. Priority Date: 12/08/2009
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: YAMAZAKI, Shunpei
• Granted Patent: US 8,558,233 B2
• Time in Patent Office: Days
• US Class Current: 257/43
• CPC Class Codes: H01L 21/3003 Hydrogenation or deuterisation, e.g. using atomic hydrogen from a plasma
• 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 29/7869 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

Abstract

One embodiment of the present invention is to achieve high mobility in a device using an oxide semiconductor and provide a highly reliable display device. An oxide semiconductor layer including a crystal region in which c-axis is aligned in a direction substantially perpendicular to a surface is formed and an oxide insulating layer is formed over and in contact with the oxide semiconductor layer. Oxygen is supplied to the oxide semiconductor layer by third heat treatment. A nitride insulating layer containing hydrogen is formed over the oxide insulating layer and fourth heat treatment is performed, so that hydrogen is supplied at least to an interface between the oxide semiconductor layer and the oxide insulating layer.

Claims

1. A semiconductor device comprising:

a first oxide semiconductor layer over a substrate having an insulating surface, the first oxide semiconductor layer including a crystal region in which c-axis is aligned in a direction perpendicular to a surface of the first oxide semiconductor layer;

a second oxide semiconductor layer over and in contact with the first oxide semiconductor layer, the second oxide semiconductor layer including a crystal region in which c-axis is aligned in the direction perpendicular to the surface;

a source electrode layer and a drain electrode layer over the first oxide semiconductor layer and the second oxide semiconductor layer;

an oxide insulating layer over and in contact with the second oxide semiconductor layer;

a gate electrode layer over the oxide insulating layer; and

a nitride insulating layer containing hydrogen over the gate electrode layer.

2. The semiconductor device according to claim 1, wherein a hydrogen concentration in the nitride insulating layer is higher than or equal to 1×

10²¹ atoms/cm³.

7. The semiconductor device according to claim 1, wherein off-state current density of a transistor comprising the first oxide semiconductor layer and the second oxide semiconductor layer is 100 aA/μ

m or less.

8. The semiconductor device according to claim 1, wherein off-state resistivity of a transistor comprising the first oxide semiconductor layer and the second oxide semiconductor layer is greater than or equal to 1×

10⁹ Ω

·

m.

9. The semiconductor device according to claim 1, wherein at least one of the first oxide semiconductor layer and the second oxide semiconductor layer comprises an oxide semiconductor comprising indium and zinc.

10. The semiconductor device according to claim 1, wherein at least one of the first oxide semiconductor layer and the second oxide semiconductor layer comprises In—

Ga—

Zn—

O.

3. A semiconductor device comprising:

a gate electrode layer over a substrate having an insulating surface;

a gate insulating layer over the gate electrode layer;

a first oxide semiconductor layer over the gate insulating layer and in contact with at least part of the gate insulating layer, the first oxide semiconductor layer including a crystal region in which c-axis is aligned in a direction perpendicular to a surface of the first oxide semiconductor layer;

a second oxide semiconductor layer over and in contact with the first oxide semiconductor layer, the second oxide semiconductor layer including a crystal region in which c-axis is aligned in the direction perpendicular to the surface;

a source electrode layer and a drain electrode layer over the first oxide semiconductor layer and the second oxide semiconductor layer;

an oxide insulating layer over and in contact with the second oxide semiconductor layer; and

a nitride insulating layer containing hydrogen over and in contact with the oxide insulating layer.

4. The semiconductor device according to claim 3, wherein a hydrogen concentration in the nitride insulating layer is higher than or equal to 1×

10²¹ atoms/cm³.

11. The semiconductor device according to claim 3, wherein off-state current density of a transistor comprising the first oxide semiconductor layer and the second oxide semiconductor layer is 100 aA/μ

m or less.

12. The semiconductor device according to claim 3, wherein off-state resistivity of a transistor comprising the first oxide semiconductor layer and the second oxide semiconductor layer is greater than or equal to 1×

10⁹ Ω

·

m.

13. The semiconductor device according to claim 3, wherein at least one of the first oxide semiconductor layer and the second oxide semiconductor layer comprises an oxide semiconductor comprising indium and zinc.

14. The semiconductor device according to claim 3, wherein at least one of the first oxide semiconductor layer and the second oxide semiconductor layer comprises In—

Ga—

Zn—

O.

5. A semiconductor device comprising:

a first oxide semiconductor layer over a substrate having an insulating surface, the first oxide semiconductor layer including a crystal region in which c-axis is aligned in a direction perpendicular to a surface of the first oxide semiconductor layer;

a second oxide semiconductor layer over and in contact with the first oxide semiconductor layer, the second oxide semiconductor layer including a crystal region in which c-axis is aligned in the direction perpendicular to the surface;

an oxide insulating layer over and in contact with the second oxide semiconductor layer; and

a nitride insulating layer containing hydrogen over and in contact with the oxide insulating layer.

15. The semiconductor device according to claim 5, wherein off-state current density of a transistor comprising the first oxide semiconductor layer and the second oxide semiconductor layer is 100 aA/μ

m or less.

16. The semiconductor device according to claim 5, wherein off-state resistivity of a transistor comprising the first oxide semiconductor layer and the second oxide semiconductor layer is greater than or equal to 1×

10⁹ Ω

·

m.

17. The semiconductor device according to claim 5, wherein at least one of the first oxide semiconductor layer and the second oxide semiconductor layer comprises an oxide semiconductor comprising indium and zinc.

18. The semiconductor device according to claim 5, wherein at least one of the first oxide semiconductor layer and the second oxide semiconductor layer comprises In—

Ga—

Zn—

O.

6. A semiconductor device comprising:

a first oxide semiconductor layer;

a second oxide semiconductor layer on the first oxide semiconductor layer, the second oxide semiconductor layer including a crystal region in which c-axis is aligned in a direction perpendicular to a surface of the second oxide semiconductor layer;

an oxide insulating layer over the second oxide semiconductor layer; and

a nitride insulating layer containing hydrogen over the oxide insulating layer.

19. The semiconductor device according to claim 6, wherein off-state current density of a transistor comprising the first oxide semiconductor layer and the second oxide semiconductor layer is 100 aA/μ

m or less.

20. The semiconductor device according to claim 6, wherein off-state resistivity of a transistor comprising the first oxide semiconductor layer and the second oxide semiconductor layer is greater than or equal to 1×

10⁹ Ω

·

m.

21. The semiconductor device according to claim 6, wherein at least one of the first oxide semiconductor layer and the second oxide semiconductor layer comprises an oxide semiconductor comprising indium and zinc.

22. The semiconductor device according to claim 6, wherein at least one of the first oxide semiconductor layer and the second oxide semiconductor layer comprises In—

Ga—

Zn—

O.