SEMICONDUCTOR DEVICE

• US 20180269327A1
• Filed: 05/18/2018
• Published: 09/20/2018
• Est. Priority Date: 08/31/2016
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: ENDO, Yuta
• Granted Patent: US 10,199,509 B2
• Time in Patent Office: Days
• CPC Class Codes: H01L 21/823412 with a particular manufacturing method of the channel structures, e.g. channel implants, halo or pocket implants, or channel materials
• CPC Class Codes: H01L 27/088 the components being field-effect transistors with insulated gate
• 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 29/1033 with insulated gate, e.g. characterised by the length, the width, the geometric contour or the doping structure with channel and gate aligned in the lengthwise direction H01L29/42376; with buried channel H01L29/7838
• CPC Class Codes: H01L 29/78648 arranged on opposing sides of the channel
• 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 29/78696 characterised by the structure of the channel, e.g. multichannel, transverse or longitudinal shape, length or width, doping structure, or the overlap or alignment between the channel and the gate, the source or the drain, or the contacting structure of the channel H01L29/78612 takes precedence; transistors having a drain offset region or a lightly doped drain [LDD] H01L29/78621

Abstract

A high-performance semiconductor device with high reliability is provided. The semiconductor device includes a first transistor, a second transistor, a first metal oxide covering at least part of the first transistor, an insulating film over the first transistor and the second transistor, and a second metal oxide over the insulating film. The first transistor includes a first gate electrode, a first gate insulating film, a first oxide, a first source electrode, a first drain electrode, a second gate insulating film, and a second gate electrode. The second transistor includes a third gate electrode, a third gate insulating film, a second oxide, a second source electrode, a second drain electrode, a fourth gate insulating film, and a fourth gate electrode. The first gate insulating film and the second gate insulating film are in contact with the first metal oxide.

Claims

1. A method for manufacturing a semiconductor device comprising:

forming a first transistor and a second transistor;

wherein the first transistor comprises;

a first oxide over a first insulating film;

a first gate insulating film over the first oxide; and

a first gate electrode over the first gate insulating film,

wherein the second transistor comprises;

a second oxide over the first insulating film;

a second gate insulating film over the second oxide; and

a second gate electrode over the second gate insulating film,

forming a second insulating film covering the first transistor and the second transistor;

forming a third insulating film by etching the second insulating film, wherein the third insulating film covers at least part of the first transistor; and

forming a fourth insulating film over the third insulating film, the first transistor and the second transistor,

wherein the third insulating film is in contact with the first gate insulating film and a first region of the first insulating film,

wherein the fourth insulating film is in contact with the second gate insulating film and a second region of the first insulating film, and

wherein the second insulating film comprises a metal oxide.

2. The method for manufacturing a semiconductor device according to claim 1,

wherein the first oxide and the second oxide each comprises indium, gallium and zinc,

wherein the first oxide comprises a channel formation region of the first transistor, and

wherein the second oxide comprises a channel formation region of the second transistor.

3. The method for manufacturing a semiconductor device according to claim 1, further comprising the step of:

forming a fifth insulating film over the fourth insulating film,

wherein the fifth insulating film comprises a metal oxide.

4. The method for manufacturing a semiconductor device according to claim 3,

wherein the fifth insulating film is formed by sputtering method, and

wherein oxygen is added to the fourth insulating film in the step of forming the fifth insulating film.

5. The method for manufacturing a semiconductor device according to claim 3,

wherein the second insulating film and the fifth insulating film each comprise aluminum.

6. The semiconductor device according to claim 1,

wherein a channel width of the first transistor is larger than a channel width of the second transistor.

7. The semiconductor device according to claim 1,

wherein a channel length of the first transistor is longer than a channel length of the second transistor.

8. A method for manufacturing a semiconductor device comprising:

forming a first oxide and a second oxide over a first insulating film;

forming a second insulating film over the first oxide and the second oxide;

forming a first gate electrode and a second gate electrode over the second insulating film, wherein the first gate electrode is over the first oxide and the second gate electrode is over the second oxide;

forming a first gate insulating film and a second gate insulating film by etching the second insulating film, wherein the first gate electrode is over the first gate insulating film and the second gate electrode is over the second gate insulating film;

forming a third insulating film over the first oxide, the first gate electrode, the second oxide and the second gate electrode;

forming a fourth insulating film by etching the third insulating film, wherein the fourth insulating film covers the first oxide; and

forming a fifth insulating film over the fourth insulating film, the second oxide and the second gate electrode,

wherein the fourth insulating film is in contact with the first gate insulating film and a first region of the first insulating film,

wherein the fifth insulating film is in contact with the second gate insulating film and a second region of the first insulating film, and

wherein the third insulating film comprises a metal oxide.

9. The method for manufacturing a semiconductor device according to claim 8, further comprising the step of:

forming a third gate electrode and a fourth gate electrode;

wherein the first oxide is formed so as to overlap the third gate electrode with the first insulating film interposed therebetween, and

wherein the second oxide is formed so as to overlap the fourth gate electrode with the first insulating film interposed therebetween.

10. The method for manufacturing a semiconductor device according to claim 8,

wherein the first oxide and the second oxide each comprises indium, gallium and zinc.

11. The method for manufacturing a semiconductor device according to claim 8, further comprising the step of:

forming a sixth insulating film over the fifth insulating film,

wherein the sixth insulating film comprises a metal oxide.

12. The method for manufacturing a semiconductor device according to claim 11,

wherein the sixth insulating film is formed by sputtering method, and

wherein oxygen is added to the fifth insulating film in the step of forming the sixth insulating film.

13. The method for manufacturing a semiconductor device according to claim 11,

wherein the third insulating film and the sixth insulating film each comprise aluminum.

14. A method for manufacturing a semiconductor device comprising:

forming a first oxide and a second oxide over a first insulating film;

forming a second insulating film over the first oxide and the second oxide;

forming a first gate electrode and a second gate electrode over the second insulating film, wherein the first gate electrode is over the first oxide and the second gate electrode is over the second oxide;

forming a third insulating film over the first oxide, the first gate electrode, the second oxide and the second gate electrode;

etching the second insulating film and the third insulating film so as to form a first gate insulating film and a second gate insulating film from the second insulating film and a fourth insulating film and a fifth insulating film from the third insulating film, wherein the first gate electrode is over the first gate insulating film and the second gate electrode is over the second gate insulating film; and

forming a sixth insulating film over the fourth insulating film and the fifth insulating film,

wherein the fourth insulating film is in contact with the first gate insulating film and covers the first oxide,

wherein the fifth insulating film is in contact with the second gate insulating film and an end portion of the fifth insulating film overlaps the second oxide,

wherein the sixth insulating film is in contact with the first gate insulating film, the second gate insulating film, the second oxide and the first insulating film, and

wherein the third insulating film comprises a metal oxide.

15. The method for manufacturing a semiconductor device according to claim 14,

wherein an end portion of the fourth insulating film and an end portion of the first gate insulating film are aligned, and

wherein an end portion of the fifth insulating film and an end portion of the second gate insulating film are aligned.

16. The method for manufacturing a semiconductor device according to claim 14, further comprising the step of:

forming a third gate electrode and a fourth gate electrode;

wherein the first oxide overlaps the third gate electrode with the first insulating film interposed therebetween, and

wherein the second oxide overlaps the fourth gate electrode with the first insulating film interposed therebetween.

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

wherein the first oxide and the second oxide each comprises indium, gallium and zinc.

18. The method for manufacturing a semiconductor device according to claim 14, further comprising the step of:

forming a seventh insulating film over the sixth insulating film,

wherein the seventh insulating film comprises a metal oxide.

19. The method for manufacturing a semiconductor device according to claim 18,

wherein the seventh insulating film is formed by a sputtering method, and

wherein oxygen is added to the sixth insulating film in the step of forming the seventh insulating film.

20. The method for manufacturing a semiconductor device according to claim 18,

wherein the third insulating film and the sixth insulating film each comprise aluminum.