SEMICONDUCTOR DEVICE AND METHOD FOR MANUFACTURING SEMICONDUCTOR DEVICE

• US 20130092924A1
• Filed: 10/01/2012
• Published: 04/18/2013
• Est. Priority Date: 10/13/2011
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: SASAGAWA, Shinya, KURATA, Motomu
• Granted Patent: US 9,287,405 B2
• Time in Patent Office: Days
• US Class Current: 257/43
• 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 29/78606 with supplementary region or layer in the thin film or in the insulated bulk substrate supporting it for controlling or increasing the safety of the device H01L29/78642, H01L29/78645 take precedence
• 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
• CPC Class Codes: H10B 41/70 the floating gate being an electrode shared by two or more components

Abstract

A miniaturized transistor having excellent electrical characteristics is provided with high yield. Further, a semiconductor device including the transistor and having high performance and high reliability is manufactured with high productivity. In a semiconductor device including a transistor in which an oxide semiconductor film including a channel formation region and low-resistance regions between which the channel formation region is sandwiched, a gate insulating film, and a gate electrode layer whose top surface and side surface are covered with an insulating film including an aluminum oxide film are stacked, a source electrode layer and a drain electrode layer are in contact with part of the oxide semiconductor film and the top surface and a side surface of the insulating film including an aluminum oxide film.

Claims

1. A semiconductor device comprising:

an oxide semiconductor film over an oxide insulating film;

a gate insulating film over the oxide semiconductor film;

a gate electrode layer over the gate insulating film overlapping with the oxide semiconductor film;

an insulating film including an aluminum oxide film covering a top surface and a side surface of the gate electrode layer; and

a wiring layer in contact with the oxide semiconductor film and a part of a top surface and a side surface of the insulating film including the aluminum oxide film.

3. The semiconductor device according to claim 1,

wherein the oxide semiconductor film comprises a channel formation region and low-resistance regions between which the channel formation region is sandwiched, and

wherein each of the low-resistance regions includes a dopant.

5. The semiconductor device according to claim 1, wherein an oxygen concentration in a region overlapping with the gate electrode layer and the insulating film including the aluminum oxide film in the oxide semiconductor film is higher than an oxygen concentration in a region other than the region overlapping with the gate electrode layer and the insulating film including the aluminum oxide film in the oxide semiconductor film.

7. The semiconductor device according to claim 1, wherein the insulating film including the aluminum oxide film is in contact with the oxide semiconductor film.

9. The semiconductor device according to claim 1, further comprising an electrode layer below the oxide semiconductor film,

wherein the electrode layer is in contact with the oxide semiconductor film and overlaps with the wiring layer.

11. The semiconductor device according to claim 1, further comprising an electrode layer below the oxide semiconductor film,

wherein the electrode layer is in contact with the oxide semiconductor film and overlaps with the wiring layer, and

wherein the electrode layer is provided over the oxide insulating film.

13. The semiconductor device according to claim 1, further comprising an electrode layer below the oxide semiconductor film,

wherein the electrode layer is in contact with the oxide semiconductor film and overlaps with the wiring layer, and

wherein the electrode layer is embedded in the oxide insulating film.

2. A semiconductor device comprising:

an oxide semiconductor film over an oxide insulating film;

a gate insulating film over the oxide semiconductor film;

a gate electrode layer over the gate insulating film overlapping with the oxide semiconductor film;

an insulating film including an aluminum oxide film covering a top surface and a side surface of the gate electrode layer;

an interlayer insulating layer over the oxide semiconductor film, the gate insulating film, the gate electrode layer, and the insulating film including the aluminum oxide film, wherein an opening reaching the oxide semiconductor film is provided in the interlayer insulating layer; and

a wiring layer in contact with the oxide semiconductor film and a part of a top surface and a side surface of the insulating film including the aluminum oxide film, the wiring layer being provided in the opening.

4. The semiconductor device according to claim 2,

wherein the oxide semiconductor film comprises a channel formation region and low-resistance regions between which the channel formation region is sandwiched, and

wherein each of the low-resistance regions includes a dopant.

6. The semiconductor device according to claim 2, wherein an oxygen concentration in a region overlapping with the gate electrode layer and the insulating film including the aluminum oxide film in the oxide semiconductor film is higher than an oxygen concentration in a region other than the region overlapping with the gate electrode layer and the insulating film including the aluminum oxide film in the oxide semiconductor film.

8. The semiconductor device according to claim 2, wherein the insulating film including the aluminum oxide film is in contact with the oxide semiconductor film.

10. The semiconductor device according to claim 2, further comprising an electrode layer below the oxide semiconductor film,

wherein the electrode layer is in contact with the oxide semiconductor film and overlaps with the wiring layer.

12. The semiconductor device according to claim 2, further comprising an electrode layer below the oxide semiconductor film,

wherein the electrode layer is in contact with the oxide semiconductor film and overlaps with the wiring layer, and

wherein the electrode layer is provided over the oxide insulating film.

14. The semiconductor device according to claim 2, further comprising an electrode layer below the oxide semiconductor film,

wherein the electrode layer is in contact with the oxide semiconductor film and overlaps with the wiring layer, and

wherein the electrode layer is embedded in the oxide insulating film.

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

forming an oxide insulating film;

forming an oxide semiconductor film over the oxide insulating film;

forming a gate insulating film over the oxide semiconductor film;

forming a gate electrode layer overlapping with the oxide semiconductor film, over the gate insulating film;

forming an insulating film including an aluminum oxide film to cover a top surface and a side surface of the gate electrode layer; and

forming a wiring layer in contact with the oxide semiconductor film and a part of a top surface and a side surface of the insulating film including the aluminum oxide film.

17. The method for manufacturing a semiconductor device, according to claim 15, further comprising a step of introducing a dopant selectively into the oxide semiconductor film using the gate electrode layer as a mask to form a low-resistance region before the step of forming the insulating film including the aluminum oxide film.

19. The method for manufacturing a semiconductor device, according to claim 15, further comprising a step of introducing oxygen into the oxide semiconductor film before the step of forming the gate electrode layer.

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

wherein the gate insulating film is etched using the gate electrode layer as a mask, and

wherein the insulating film including the aluminum oxide film is in contact with the oxide semiconductor film.

23. The method for manufacturing a semiconductor device, according to claim 15, further comprising a step of forming an electrode layer below the oxide semiconductor film, the electrode layer being in contact with the oxide semiconductor film and overlapping with the wiring layer.

25. The method for manufacturing a semiconductor device, according to claim 15, further comprising a step of performing planarization treatment on a surface of the oxide insulating film before the step of forming the oxide semiconductor film.

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

forming an oxide insulating film;

forming an oxide semiconductor film over the oxide insulating film;

forming a gate insulating film over the oxide semiconductor film;

forming a gate electrode layer overlapping with the oxide semiconductor film, over the gate insulating film;

forming an insulating film including an aluminum oxide film to cover a top surface and a side surface of the gate electrode layer;

forming an interlayer insulating layer over the oxide semiconductor film, the gate insulating film, the gate electrode layer, and the insulating film including the aluminum oxide film;

forming an opening in the interlayer insulating layer to expose a part of the oxide semiconductor film and a part of a top surface and a side surface of the insulating film including the aluminum oxide film; and

forming a wiring layer in contact with the part of the oxide semiconductor film and the part of the top surface and the side surface of the insulating film including the aluminum oxide film in the opening.

18. The method for manufacturing a semiconductor device, according to claim 16, further comprising a step of introducing a dopant selectively into the oxide semiconductor film using the gate electrode layer as a mask to form a low-resistance region before the step of forming the insulating film including the aluminum oxide film.

20. The method for manufacturing a semiconductor device, according to claim 16, further comprising a step of introducing oxygen into the oxide semiconductor film before the step of forming the gate electrode layer.

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

wherein the gate insulating film is etched using the gate electrode layer as a mask, and

wherein the insulating film including the aluminum oxide film is in contact with the oxide semiconductor film.

24. The method for manufacturing a semiconductor device, according to claim 16, further comprising a step of forming an electrode layer below the oxide semiconductor film, the electrode layer being in contact with the oxide semiconductor film and overlapping with the wiring layer.

26. The method for manufacturing a semiconductor device, according to claim 16, further comprising a step of performing planarization treatment on a surface of the oxide insulating film before the step of forming the oxide semiconductor film.