Granted Patent B2

US 12,727,451 · App. 18/021,317 · Granted Sep 1, 2026

Inventors: Shunpei Yamazaki (Tokyo, JP); Yoshihiro Komatsu (Ebina, JP); Shunichi Ito (Atsugi, JP); Shinobu Kawaguchi (Isehara, JP); Masahiro Takahashi (Atsugi, JP)

Assignee: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.

H10P95/90

Abstract

Claims (69)

1 . A method for manufacturing a semiconductor device comprising a transistor, comprising the steps of:

forming an oxide semiconductor layer;

forming a first insulator over the oxide semiconductor layer;

forming an opening reaching the oxide semiconductor layer in the first insulator;

forming a second insulator in the opening;

forming a first conductor as a gate electrode over the second insulator and in the opening;

forming a third insulator over and in contact with the first conductor by a sputtering method;

forming a fourth insulator in contact with a top surface and a side surface of the third insulator; and

performing heat treatment so that hydrogen in the oxide semiconductor layer and the second insulator is moved into and absorbed by the third insulator.

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

wherein the third insulator is formed using a sputtering target comprising aluminum and a gas comprising oxygen.

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

wherein a temperature of the heat treatment is higher than or equal to 300° C. and lower than or equal to 550° C., and

wherein time for the heat treatment is longer than or equal to 2 hours and shorter than or equal to 16 hours.

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

wherein the third insulator comprises an amorphous structure.

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

wherein the third insulator comprises a stacked-layer structure, and

wherein the stacked-layer structure comprises an amorphous structure and a polycrystalline structure over the amorphous structure.

6 . A method for manufacturing a semiconductor device comprising a transistor, comprising the steps of:

forming an oxide semiconductor film;

forming a first conductive film over the oxide semiconductor film;

processing the oxide semiconductor film and the first conductive film into an island shape to form an oxide semiconductor layer and a conductive layer;

forming a first insulator over the conductive layer;

forming an opening reaching the oxide semiconductor layer in the conductive layer and the first insulator and forming a source electrode and a drain electrode from the conductive layer;

forming an insulating film over the first insulator and the opening;

forming a second conductive film over the insulating film;

performing CMP treatment on the insulating film and the second conductive film until a top surface of the first insulator is exposed to form a second insulator as a gate insulating film and a first conductor as a gate electrode;

forming a third insulator over the first insulator, the second insulator, and the first conductor by a sputtering method;

forming a fourth insulator in contact with a top surface and a side surface of the third insulator; and

performing heat treatment so that hydrogen in the oxide semiconductor layer and the second insulator is moved into and absorbed by the third insulator.

7 . The method for manufacturing a semiconductor device, according to claim 6 ,

wherein the third insulator is formed using a sputtering target comprising aluminum and a gas comprising oxygen.

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

wherein a temperature of the heat treatment is higher than or equal to 300° C. and lower than or equal to 550° C., and

wherein time for the heat treatment is longer than or equal to 2 hours and shorter than or equal to 16 hours.

9 . The method for manufacturing a semiconductor device, according to claim 6 ,

wherein the third insulator comprises an amorphous structure.

10 . The method for manufacturing a semiconductor device, according to claim 6 ,

wherein the third insulator comprises a stacked-layer structure, and

wherein the stacked-layer structure comprises an amorphous structure and a polycrystalline structure over the amorphous structure.

11 . A method for manufacturing a semiconductor device comprising a transistor, comprising the steps of:

forming an oxide semiconductor film;

forming a first conductive film over the oxide semiconductor film;

processing the oxide semiconductor film and the first conductive film into an island shape to form an oxide semiconductor layer and a conductive layer;

forming a first insulator over the conductive layer;

forming an opening reaching the oxide semiconductor layer in the conductive layer and the first insulator and forming a source electrode and a drain electrode from the conductive layer;

forming an insulating film over the first insulator and the opening;

forming a second conductive film over the insulating film;

performing CMP treatment on the insulating film and the second conductive film until a top surface of the first insulator is exposed to form a second insulator as a gate insulating film and a first conductor as a gate electrode;

forming a third insulator over the first insulator, the second insulator, and the first conductor by a sputtering method;

forming a fourth insulator in contact with a top surface and a side surface of the third insulator; and

performing heat treatment,

wherein a hydrogen concentration in the third insulator is increased by the heat treatment, and

wherein a hydrogen concentration in the second insulator and a hydrogen concentration in the oxide semiconductor layer are decreased by the heat treatment.

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

wherein the third insulator is formed using a sputtering target comprising aluminum and a gas comprising oxygen.

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

wherein a temperature of the heat treatment is higher than or equal to 300° C. and lower than or equal to 550° C., and

wherein time for the heat treatment is longer than or equal to 2 hours and shorter than or equal to 16 hours.

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

wherein the heat treatment is performed after forming the fourth insulator.

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

wherein the fourth insulator is in contact with a side surface of the first insulator.

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

wherein the third insulator comprises an amorphous structure.

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

wherein the third insulator comprises a stacked-layer structure, and

wherein the stacked-layer structure comprises an amorphous structure and a polycrystalline structure over the amorphous structure.

Assignments (1)

Priority Claims (1)

Continuity (1)

References Cited (35)