Manufacturing method of the semiconductor device

• US 9,299,814 B2
• Filed: 12/02/2014
• Issued: 03/29/2016
• Est. Priority Date: 01/12/2011
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Yamazaki, Shunpei
• Primary Examiner(s): Maldonado, Julio J
• Assistant Examiner(s): Hossain, Moazzam
• Application Number:
  US14/557,915
• Publication Number:
  US 20150087112A1
• Time in Patent Office: 483 Days
• Field of Search: 438/608, 438/722, 257/43, 257/E29.296
• US Class Current: 1/1
• 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 21/02631 Physical deposition at reduced pressure, e.g. MBE, sputtering, evaporation
• 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 29/66969 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 29/78648 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

Abstract

The semiconductor device is manufactured through the following steps: after first heat treatment is performed on an oxide semiconductor film, the oxide semiconductor film is processed to form an oxide semiconductor layer; immediately after that, side walls of the oxide semiconductor layer are covered with an insulating oxide; and in second heat treatment, the side surfaces of the oxide semiconductor layer are prevented from being exposed to a vacuum and defects (oxygen deficiency) in the oxide semiconductor layer are reduced.

Claims

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

forming a first insulating film over a substrate;

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

performing a first heat treatment to the oxide semiconductor film;

patterning the oxide semiconductor film after performing the first heat treatment to form an oxide semiconductor layer that includes a region comprising c-axis-aligned crystalline oxide semiconductor that is a non-single-crystal oxide material;

forming a second insulating film covering the oxide semiconductor layer; and

performing a second heat treatment to the oxide semiconductor layer after forming the second insulating film,

wherein a part of oxygen in the first insulating film is desorbed during the first heat treatment, and

wherein a part of the desorbed oxygen is supplied to the oxide semiconductor film.

2. The method according to claim 1, wherein the first insulating film is formed using an insulating oxide containing more oxygen than oxygen in a stoichiometric proportion.

3. The method according to claim 1, wherein the first heat treatment is performed by a heat treatment on the substrate.

4. The method according to claim 1, wherein a concentration of hydrogen in the oxide semiconductor film is lowered after performing the first heat treatment.

5. The method according to claim 1, further comprising the step of forming a first conductive layer and a second conductive layer over the first insulating film, wherein each of the first conductive layer and the second conductive layer is a metal film having a thickness ranging from 100 nm to 300 nm.

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

forming a first insulating film over a substrate;

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

patterning the oxide semiconductor film to form an oxide semiconductor layer that includes a region comprising c-axis-aligned crystalline oxide semiconductor that is a non-single-crystal oxide material;

forming a second insulating film covering the oxide semiconductor layer; and

performing a second heat treatment to the oxide semiconductor layer after forming the second insulating film,

wherein a part of oxygen in the second insulating film is desorbed during the second heat treatment, and

wherein a part of the desorbed oxygen is supplied to the oxide semiconductor layer.

7. The method according to claim 6, further comprising the step of performing a first heat treatment to the oxide semiconductor film before the patterning the oxide semiconductor film.

8. The method according to claim 7,

wherein a part of oxygen in the first insulating film is desorbed during the first heat treatment, and

wherein a part of the desorbed oxygen is supplied to the oxide semiconductor film.

9. The method according to claim 6, wherein the first insulating film is formed using an insulating oxide containing more oxygen than oxygen in a stoichiometric proportion.

10. The method according to claim 7, wherein the first heat treatment is performed by a heat treatment on the substrate.

11. The method according to claim 7, wherein a concentration of hydrogen in the oxide semiconductor film is lowered after performing the first heat treatment.

12. The method according to claim 6, further comprising the step of forming a first conductive layer and a second conductive layer over the first insulating film, wherein each of the first conductive layer and the second conductive layer is a metal film having a thickness ranging from 100 nm to 300 nm.

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

forming a first insulating film over a substrate;

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

patterning the oxide semiconductor film to form an oxide semiconductor layer that includes a region comprising c-axis-aligned crystalline oxide semiconductor that is a non-single-crystal oxide material;

forming a second insulating film covering the oxide semiconductor layer;

forming a third insulating film covering the second insulating film;

performing a second heat treatment to the oxide semiconductor layer after forming the third insulating film,

wherein a part of oxygen in the third insulating film is desorbed during the second heat treatment, and

wherein a part of the desorbed oxygen is supplied to the oxide semiconductor layer.

14. The method according to claim 13, further comprising the step of performing a first heat treatment to the oxide semiconductor film before the patterning the oxide semiconductor film.

15. The method according to claim 14,

wherein a part of oxygen in the first insulating film is desorbed during the first heat treatment, and

wherein a part of the desorbed oxygen is supplied to the oxide semiconductor film.

16. The method according to claim 14, wherein the first insulating film is formed using an insulating oxide containing more oxygen than oxygen in a stoichiometric proportion.

17. The method according to claim 14, wherein the first heat treatment is performed by a heat treatment on the substrate.

18. The method according to claim 14, wherein a concentration of hydrogen in the oxide semiconductor film is lowered after performing the first heat treatment.

19. The method according to claim 13, further comprising the step of forming a first conductive layer and a second conductive layer over the first insulating film, wherein each of the first conductive layer and the second conductive layer is a metal film having a thickness ranging from 100 nm to 300 nm.