MANUFACTURING METHOD OF SEMICONDUCTOR DEVICE

• US 20120258575A1
• Filed: 04/02/2012
• Published: 10/11/2012
• Est. Priority Date: 04/06/2011
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: SATO, Yuhei, SATO, Keiji, SASAKI, Toshinari, MARUYAMA, Tetsunori, ISOBE, Atsuo, TEZUKA, Sachiaki, MURAKAWA, Tsutomu
• Granted Patent: US 9,960,278 B2
• Time in Patent Office: Days
• US Class Current: 438/151
• CPC Class Codes: H01L 21/477 Thermal treatment for modifying the properties of semiconductor bodies, e.g. annealing, sintering H01L21/38 - H01L21/449 and H01L21/461 - H01L21/475 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

Abstract

To provide a highly reliable semiconductor device manufactured by giving stable electric characteristics to a semiconductor device including an oxide semiconductor. In a manufacturing process of a transistor, an oxide semiconductor layer, a source electrode layer, a drain electrode layer, a gate insulating film, a gate electrode layer, and an aluminum oxide film are formed in this order, and then heat treatment is performed on the oxide semiconductor layer and the aluminum oxide film, whereby an oxide semiconductor layer from which an impurity containing a hydrogen atom is removed and which includes a region containing oxygen more than the stoichiometric proportion is formed. In addition, when the aluminum oxide film is formed, entry and diffusion of water or hydrogen into the oxide semiconductor layer from the air due to heat treatment in a manufacturing process of a semiconductor device or an electronic appliance including the transistor can be prevented.

Claims

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

forming an oxide semiconductor layer;

forming a gate insulating film adjacent to the oxide semiconductor layer;

forming a gate electrode layer adjacent to the oxide semiconductor layer with the gate insulating film interposed therebetween,

forming an aluminum oxide film over the gate electrode layer; and

performing heat treatment on at least the oxide semiconductor layer,

wherein a thickness of the aluminum oxide film is greater than 50 nm and less than or equal to 500 nm.

2. The method for manufacturing a semiconductor device, according to claim 1, further comprising the step of performing heat treatment on the oxide semiconductor layer just after the oxide semiconductor layer is formed.

3. The method for manufacturing a semiconductor device, according to claim 1, further comprising the step of forming an interlayer insulating film over the aluminum oxide film.

4. The method for manufacturing a semiconductor device, according to claim 3, wherein the interlayer insulating film is formed of silicon oxynitride.

5. The method for manufacturing a semiconductor device, according to claim 1, further comprising the step of adding an impurity element to the oxide semiconductor layer by an ion doping method or an ion implantation method after the gate electrode layer is formed.

6. The method for manufacturing a semiconductor device, according to claim 1, wherein the oxide semiconductor layer is formed while being heated.

7. The method for manufacturing a semiconductor device, according to claim 1, wherein the gate insulating film includes a region in which an oxygen content is higher than a stoichiometric proportion of the gate insulating film.

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

forming a source electrode layer and a drain electrode layer over the oxide semiconductor layer,

wherein a channel length determined by a distance between the source electrode layer and the drain electrode layer which are adjacent to each other over the oxide semiconductor layer is less than or equal to 2 μ

m.

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

forming a base insulating film;

forming an oxide semiconductor layer over and in contact with the base insulating film;

forming a source electrode layer and a drain electrode layer over the oxide semiconductor layer;

forming a gate insulating film over and in contact with the oxide semiconductor layer, the source electrode layer, and the drain electrode layer;

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

forming an aluminum oxide film over and in contact with the gate insulating film and the gate electrode layer; and

performing heat treatment on the oxide semiconductor layer,

wherein a thickness of the aluminum oxide film is greater than 50 nm and less than or equal to 500 nm.

10. The method for manufacturing a semiconductor device, according to claim 9, further comprising the step of performing heat treatment on the oxide semiconductor layer just after the oxide semiconductor layer is formed.

11. The method for manufacturing a semiconductor device, according to claim 9, further comprising the step of forming an interlayer insulating film over the aluminum oxide film.

12. The method for manufacturing a semiconductor device, according to claim 11, wherein the interlayer insulating film is formed of silicon oxynitride.

13. The method for manufacturing a semiconductor device, according to claim 9, further comprising the step of adding an impurity element to the oxide semiconductor layer by an ion doping method or an ion implantation method after the gate electrode layer is formed.

14. The method for manufacturing a semiconductor device, according to claim 9, wherein the oxide semiconductor layer is formed while being heated.

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

wherein the base insulating film includes a region in which an oxygen content is higher than a stoichiometric proportion of the base insulating film or the gate insulating film includes a region in which an oxygen content is higher than a stoichiometric proportion of the gate insulating film.

16. The method for manufacturing a semiconductor device, according to claim 9, wherein a channel length determined by a distance between the source electrode layer and the drain electrode layer which are adjacent to each other over the oxide semiconductor layer is less than or equal to 2 μ

m.

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

manufacturing a transistor by a method comprising the steps of;

forming a base insulating film;

forming an oxide semiconductor layer over and in contact with the base insulating film;

forming a source electrode layer and a drain electrode layer over the oxide semiconductor layer;

forming a gate insulating film over and in contact with the oxide semiconductor layer, the source electrode layer, and the drain electrode layer;

forming a gate electrode layer over the gate insulating film in a region overlapping with the oxide semiconductor layer; and

forming an aluminum oxide film over and in contact with the gate insulating film and the gate electrode layer; and

performing heat treatment on the transistor,

wherein a thickness of the aluminum oxide film is greater than 50 nm and less than or equal to 500 nm.

18. The method for manufacturing a semiconductor device, according to claim 17, further comprising the step of performing heat treatment on the oxide semiconductor layer just after the oxide semiconductor layer is formed.

19. The method for manufacturing a semiconductor device, according to claim 17, further comprising the step of forming an interlayer insulating film over the aluminum oxide film.

20. The method for manufacturing a semiconductor device, according to claim 19, wherein the interlayer insulating film is formed of silicon oxynitride.

21. The method for manufacturing a semiconductor device, according to claim 17, further comprising the step of adding an impurity element to the oxide semiconductor layer by an ion doping method or an ion implantation method after the gate electrode layer is formed.

22. The method for manufacturing a semiconductor device, according to claim 17, wherein the oxide semiconductor layer is formed while being heated.

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

wherein the base insulating film includes a region in which an oxygen content is higher than a stoichiometric proportion of the base insulating film or the gate insulating film includes a region in which an oxygen content is higher than a stoichiometric proportion of the gate insulating film.

24. The method for manufacturing a semiconductor device, according to claim 17, wherein a channel length determined by a distance between the source electrode layer and the drain electrode layer which are adjacent to each other over the oxide semiconductor layer is less than or equal to 2 μ

m.