MANUFACTURING METHOD OF SEMICONDUCTOR DEVICE

• US 20120319101A1
• Filed: 05/31/2012
• Published: 12/20/2012
• Est. Priority Date: 06/17/2011
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: SASAGAWA, Shinya, FUJIKI, Hiroshi, IEDA, Yoshinori
• Granted Patent: US 8,901,554 B2
• Time in Patent Office: Days
• US Class Current: 257/43
• CPC Class Codes: H01L 21/02164 the material being a silicon oxide, e.g. SiO2
• CPC Class Codes: H01L 21/02178 the material containing aluminium, e.g. Al2O3
• 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 21/47573 Etching the layer
• CPC Class Codes: H01L 29/41733 for thin film transistors with insulated gate
• CPC Class Codes: H01L 29/66742 Thin film unipolar transistors
• CPC Class Codes: H01L 29/66969 of devices having semiconductor bodies not comprising group 14 or group 13/15 materials comprising selenium or tellurium in uncombined form other than as impurities in semiconductor bodies of other materials, comprising cuprous oxide or cuprous iodide H01L21/02365
• 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 first insulating film in contact with an oxide semiconductor film and a second insulating film are stacked in this order over an electrode film of a transistor including the oxide semiconductor film, an etching mask is formed over the second insulating film, an opening portion exposing the electrode film is formed by etching a portion of the first insulating film and a portion of the second insulating film, the opening portion exposing the electrode film is exposed to argon plasma, the etching mask is removed, and a conductive film is formed in the opening portion exposing the electrode film. The first insulating film is an insulating film whose oxygen is partly released by heating. The second insulating film is less easily etched than the first insulating film and has a lower gas-permeability than the first insulating film.

Claims

1. A semiconductor device comprising:

a semiconductor film that comprises a channel formation region comprising an oxide semiconductor;

an electrode adjacent to the semiconductor film; and

a first insulating film over the semiconductor film and the electrode;

a second insulating film over the first insulating film;

a conductive film over the second insulating film, wherein the conductive film is electrically connected to the electrode through an opening of the first insulating film and an opening of the second insulating film,

wherein a first angle between a first side surface of the first insulating film and a bottom surface of the first insulating film is larger than a second angle between a second side surface of the second insulating film and a bottom surface of the second insulating film, and

wherein the first side surface and the second side surface are in contact with the conductive film.

2. The semiconductor device according to claim 1, further comprising a gate electrode over the semiconductor film.

3. The semiconductor device according to claim 1, further comprising:

a third insulating film over the second insulating film,

wherein the first angle is larger than a third angle between a third side surface of the third insulating film and a bottom surface of the third insulating film.

4. The semiconductor device according to claim 1, wherein the oxide semiconductor comprises an In—

Ga—

Zn-based oxide.

5. The semiconductor device according to claim 1,

wherein the first insulating film comprises one of a silicon oxide, a silicon oxynitride, and a silicon nitride oxide, and

wherein the second insulating film comprises aluminum oxide.

6. A manufacturing method of a semiconductor device, comprising:

forming a semiconductor film that comprises a channel formation region comprising an oxide semiconductor, and an electrode film adjacent to the semiconductor film;

forming a first insulating film in contact with the semiconductor film and over the electrode film, and a second insulating film over the first insulating film;

forming an etching mask including a first opening portion over the second insulating film;

forming a second opening portion exposing the electrode film by etching a first portion of the first insulating film and a second portion of the second insulating film, wherein the first portion and the second portion overlap with the first opening portion;

exposing the second opening portion to argon plasma;

removing the etching mask; and

forming a conductive film in the second opening portion,

wherein the first insulating film is an insulating film whose oxygen is partly released by heating, and

wherein the second insulating film is less easily etched than the first insulating film and has a higher gas barrier property than the first insulating film.

7. The manufacturing method of a semiconductor device according to claim 6, further comprising:

forming a gate electrode over the semiconductor film.

8. The manufacturing method of a semiconductor device according to claim 6,

wherein the first insulating film comprises one of a silicon oxide, a silicon oxynitride, and a silicon nitride oxide, and

wherein the second insulating film comprises an aluminum oxide.

9. The manufacturing method of a semiconductor device according to claim 6, wherein the oxide semiconductor comprises an In—

Ga—

Zn-based oxide.

10. A manufacturing method of a semiconductor device, comprising:

forming a semiconductor film that comprises a channel formation region comprising an oxide semiconductor, and an electrode film adjacent to the semiconductor film;

forming a first insulating film in contact with the semiconductor film and over the electrode film, and a second insulating film over the first insulating film;

forming an etching mask including a first opening portion over the second insulating film;

forming a second opening portion exposing the electrode film by etching a first portion of the first insulating film and a second portion of the second insulating film, wherein the first portion and the second portion overlap with the first opening portion;

removing the etching mask;

subjecting the second opening portion to reverse sputtering; and

forming a conductive film in the second opening portion by a sputtering method,

wherein the first insulating film is an insulating film whose oxygen is partly released by heating, and

wherein the second insulating film is less easily etched than the first insulating film and has a higher gas barrier property than the first insulating film.

11. The manufacturing method of a semiconductor device according to claim 10, further comprising:

forming a gate electrode over the semiconductor film.

12. The manufacturing method of a semiconductor device according to claim 10,

wherein the first insulating film comprises one of a silicon oxide, a silicon oxynitride, and a silicon nitride oxide, and

wherein the second insulating film comprises an aluminum oxide.

13. The manufacturing method of a semiconductor device according to claim 10, wherein the oxide semiconductor comprises an In—

Ga—

Zn-based oxide.

14. A manufacturing method of a semiconductor device, comprising:

forming a semiconductor film that comprises a channel formation region comprising an oxide semiconductor, and an electrode film adjacent to the semiconductor film;

forming a first insulating film in contact with the semiconductor film and over the electrode film, a second insulating film over the first insulating film, and a third insulating film over the second insulating film;

forming an etching mask including a first opening portion over the third insulating film;

forming a second opening portion exposing the electrode film by etching a first portion of the first insulating film, a second portion of the second insulating film, and a third portion of the third insulating film, wherein the first portion, the second portion, and the third portion overlap with the first opening portion;

exposing the second opening portion to argon plasma;

removing the etching mask; and

forming a conductive film in the second opening portion,

wherein the first insulating film is an insulating film whose oxygen is partly released by heating, and

wherein the second insulating film is less easily etched than the first insulating film and has a higher gas barrier property than the first insulating film.

15. The manufacturing method of a semiconductor device according to claim 14, further comprising:

forming a gate electrode over the semiconductor film.

16. The manufacturing method of a semiconductor device according to claim 14,

wherein each of the first insulating film and the third insulating film comprises one of a silicon oxide, a silicon oxynitride, and a silicon nitride oxide, and

wherein the second insulating film comprises an aluminum oxide.

17. The manufacturing method of a semiconductor device according to claim 14,

wherein the third insulating film is thicker than the first insulating film.

18. The manufacturing method of a semiconductor device according to claim 14, wherein the oxide semiconductor comprises an In—

Ga—

Zn-based oxide.

19. A manufacturing method of a semiconductor device, comprising:

forming a semiconductor film that comprises a channel formation region comprising an oxide semiconductor, and an electrode film adjacent to the semiconductor film;

forming a first insulating film in contact with the semiconductor film and over the electrode film, a second insulating film over the first insulating film, and a third insulating film over the second insulating film;

forming an etching mask including a first opening portion over the third insulating film;

forming a second opening portion exposing the electrode film by etching a first portion of the first insulating film, a second portion of the second insulating film, and a third portion of the third insulating film, wherein the first portion, the second portion, and the third portion overlap with the first opening portion;

removing the etching mask;

subjecting the second opening portion to reverse sputtering; and

forming a conductive film in the second opening portion by a sputtering method,

wherein the first insulating film is an insulating film whose oxygen is partly released by heating, and

wherein the second insulating film is less easily etched than the first insulating film and has a higher gas barrier property than the first insulating film.

20. The manufacturing method of a semiconductor device according to claim 19, further comprising:

forming a gate electrode over the semiconductor film.

21. The manufacturing method of a semiconductor device according to claim 19,

wherein each of the first insulating film and the third insulating film comprises one of a silicon oxide, a silicon oxynitride, and a silicon nitride oxide, and

wherein the second insulating film comprises an aluminum oxide.

22. The manufacturing method of a semiconductor device according to claim 19,

wherein the third insulating film is thicker than the first insulating film.

23. The manufacturing method of a semiconductor device according to claim 19, wherein the oxide semiconductor comprises an In—

Ga—

Zn-based oxide.