Method for manufacturing semiconductor device comprising adding oxygen to buffer film and insulating film

• US 10,361,290 B2
• Filed: 03/12/2015
• Issued: 07/23/2019
• Est. Priority Date: 03/14/2014
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Yamazaki, Shunpei, Jintyou, Masami, Shima, Yukinori
• Primary Examiner(s): Ho, Anthony
• Assistant Examiner(s): Hoque, Mohammad M
• Application Number:
  US14/645,781
• Publication Number:
  US 20150263141A1
• Time in Patent Office: 1,594 Days
• Field of Search: 438104
• CPC Class Codes: H01L 21/02326 into a nitride layer, e.g. changing SiN to SiON
• CPC Class Codes: H01L 21/0234 treatment by exposure to a plasma
• CPC Class Codes: H01L 21/02472 Oxides
• CPC Class Codes: H01L 21/02483 Oxide semiconducting materials not being Group 12/16 materials, e.g. ternary compounds
• 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 21/02573 Conductivity type
• CPC Class Codes: H01L 21/0262 Reduction or decomposition of gaseous compounds, e.g. CVD
• CPC Class Codes: H01L 29/42384 for thin film field effect transistors, e.g. characterised by the thickness or the shape of the insulator or the dimensions, the shape or the lay-out of the conductor
• CPC Class Codes: H01L 29/4908 for thin film semiconductor, e.g. gate of TFT
• CPC Class Codes: H01L 29/4966 the conductor material next to the insulator being a composite material, e.g. organic material, TiN, MoSi2 H01L29/4908, H01L29/4983 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 29/78621 with LDD structure or an extension or an offset region or characterised by the doping profile
• 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

Provided is a method for manufacturing a semiconductor device whose electric characteristics are prevented from being varied and whose reliability is improved. In the method, an insulating film is formed over an oxide semiconductor film, a buffer film is formed over the insulating film, oxygen is added to the buffer film and the insulating film, a conductive film is formed over the buffer film to which oxygen is added, and an impurity element is added to the oxide semiconductor film using the conductive film as a mask. An insulating film containing hydrogen and overlapping with the oxide semiconductor film may be formed after the impurity element is added to the oxide semiconductor film.

Claims

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

forming an insulating film over an oxide semiconductor film;

forming a metal oxide film over the insulating film;

adding oxygen to the metal oxide film and the insulating film by an ion doping method, an ion implantation method, or plasma treatment after forming the metal oxide film;

forming a conductive film over the metal oxide film to which oxygen is added; and

adding an impurity element to the oxide semiconductor film using the conductive film as a mask.

2. The method for manufacturing the semiconductor device, according to claim 1, wherein the metal oxide film has an end portion overlapping with the oxide semiconductor film.

3. The method for manufacturing the semiconductor device, according to claim 1, wherein the conductive film serves as a gate electrode.

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

wherein the metal oxide film to which oxygen is added is a semiconductor, and

wherein the metal oxide film to which oxygen is added and the conductive film collectively serve as a gate electrode.

5. The method for manufacturing the semiconductor device, according to claim 1, wherein the metal oxide film contains one or more of indium, zinc, titanium, tungsten, tantalum, and molybdenum.

6. The method for manufacturing the semiconductor device, according to claim 1, wherein heat treatment is performed after oxygen is added to the metal oxide film and the insulating film.

7. The method for manufacturing the semiconductor device, according to claim 1, wherein the impurity element is one or more of a rare gas, hydrogen, boron, nitrogen, fluorine, aluminum, and phosphorus.

26. The method for manufacturing the semiconductor device, according to claim 1, wherein the impurity element is added by an ion doping method, an ion implantation method, or a plasma treatment method.

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

forming an insulating film over an oxide semiconductor film;

forming a metal oxide film over the insulating film;

adding oxygen to the metal oxide film and the insulating film by an ion doping method, an ion implantation method, or plasma treatment after forming the metal oxide film;

forming a conductive film over the metal oxide film to which oxygen is added;

adding an impurity element to the oxide semiconductor film using the conductive film as a mask; and

forming an insulating film containing hydrogen and overlapping with the oxide semiconductor film.

9. The method for manufacturing the semiconductor device, according to claim 8, wherein the metal oxide film has an end portion overlapping with the oxide semiconductor film.

10. The method for manufacturing the semiconductor device, according to claim 8, wherein the conductive film serves as a gate electrode.

11. The method for manufacturing the semiconductor device, according to claim 8,

wherein the metal oxide film to which oxygen is added is a semiconductor, and

wherein the metal oxide film to which oxygen is added and the conductive film collectively serve as a gate electrode.

12. The method for manufacturing the semiconductor device, according to claim 8, wherein the metal oxide film contains one or more of indium, zinc, titanium, tungsten, tantalum, and molybdenum.

13. The method for manufacturing the semiconductor device, according to claim 8, wherein heat treatment is performed after oxygen is added to the metal oxide film and the insulating film.

14. The method for manufacturing the semiconductor device, according to claim 8, wherein the insulating film containing hydrogen contains nitrogen.

15. The method for manufacturing the semiconductor device, according to claim 8, wherein the insulating film containing hydrogen is a silicon nitride film.

16. The method for manufacturing the semiconductor device, according to claim 8, wherein the impurity element is one or more of a rare gas, hydrogen, boron, nitrogen, fluorine, aluminum, and phosphorus.

27. The method for manufacturing the semiconductor device, according to claim 8, wherein the impurity element is added by an ion doping method, an ion implantation method, or a plasma treatment method.

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

forming an insulating film over an oxide semiconductor film;

forming a metal oxide film over the insulating film;

adding oxygen to the metal oxide film and the insulating film by an ion doping method, an ion implantation method, or plasma treatment after forming the metal oxide film;

forming a conductive film over the metal oxide film to which oxygen is added;

etching the insulating film to which oxygen is added and the metal oxide film to which oxygen is added to expose part of the oxide semiconductor film;

adding an impurity element to the oxide semiconductor film using the conductive film as a mask; and

forming an insulating film containing hydrogen and overlapping with the oxide semiconductor film.

18. The method for manufacturing the semiconductor device, according to claim 17, wherein the metal oxide film has an end portion overlapping with the oxide semiconductor film.

19. The method for manufacturing the semiconductor device, according to claim 17, wherein the conductive film serves as a gate electrode.

20. The method for manufacturing the semiconductor device, according to claim 17,

wherein the metal oxide film to which oxygen is added is a semiconductor, and

wherein the metal oxide film to which oxygen is added and the conductive film collectively serve as a gate electrode.

21. The method for manufacturing the semiconductor device, according to claim 17, wherein the metal oxide film contains one or more of indium, zinc, titanium, tungsten, tantalum, and molybdenum.

22. The method for manufacturing the semiconductor device, according to claim 17, wherein heat treatment is performed after oxygen is added to the metal oxide film and the insulating film.

23. The method for manufacturing the semiconductor device, according to claim 17, wherein the insulating film containing hydrogen contains nitrogen.

24. The method for manufacturing the semiconductor device, according to claim 17, wherein the insulating film containing hydrogen is a silicon nitride film.

25. The method for manufacturing the semiconductor device, according to claim 17, wherein the impurity element is one or more of a rare gas, hydrogen, boron, nitrogen, fluorine, aluminum, and phosphorus.

28. The method for manufacturing the semiconductor device, according to claim 17, wherein the impurity element is added by an ion doping method, an ion implantation method, or a plasma treatment method.

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

forming an insulating film over an oxide semiconductor film;

forming a metal nitride film over the insulating film;

adding oxygen to the metal nitride film and the insulating film by an ion doping method, an ion implantation method, or plasma treatment after forming the metal nitride film;

forming a conductive film over the metal nitride film to which oxygen is added; and

adding an impurity element to the oxide semiconductor film using the conductive film as a mask.

30. The method for manufacturing the semiconductor device, according to claim 29, wherein the metal nitride film has an end portion overlapping with the oxide semiconductor film.

31. The method for manufacturing the semiconductor device, according to claim 29, wherein the conductive film serves as a gate electrode.

32. The method for manufacturing the semiconductor device, according to claim 29,

wherein the metal nitride film to which oxygen is added is a semiconductor, and

wherein the metal nitride film to which oxygen is added and the conductive film collectively serve as a gate electrode.

33. The method for manufacturing the semiconductor device, according to claim 29, wherein the metal nitride film contains one or more of indium, zinc, titanium, tungsten, tantalum, and molybdenum.

34. The method for manufacturing the semiconductor device, according to claim 29, wherein heat treatment is performed after oxygen is added to the metal nitride film and the insulating film.

35. The method for manufacturing the semiconductor device, according to claim 29, wherein the impurity element is one or more of a rare gas, hydrogen, boron, nitrogen, fluorine, aluminum, and phosphorus.