Method for manufacturing semiconductor device

• US 8,343,817 B2
• Filed: 08/05/2009
• Issued: 01/01/2013
• Est. Priority Date: 08/08/2008
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Miyairi, Hidekazu, Akimoto, Kengo, Nakamura, Yasuo
• Primary Examiner(s): Lee, Cheung
• Application Number:
  US12/535,713
• Publication Number:
  US 20100035379A1
• Time in Patent Office: 1,245 Days
• Field of Search: 438/608, 438/609, 438/621, 257/E21.046, 257/E21.062, 257/E21.424, 257/E21.457
• US Class Current: 438/151
• CPC Class Codes: H01L 21/02323 introduction of oxygen
• CPC Class Codes: H01L 21/02565 Oxide semiconducting materials not being Group 12/16 materials, e.g. ternary compounds
• CPC Class Codes: H01L 21/32139 using masks
• CPC Class Codes: H01L 21/465 Chemical or electrical treatment, e.g. electrolytic etching to form insulating layers H01L21/469
• CPC Class Codes: H01L 21/467 using masks
• CPC Class Codes: H01L 21/4763 Deposition of non-insulating, e.g. conductive -, resistive -, layers on insulating layers; After-treatment of these layers manufacture of electrodes H01L21/28, H01L21/44
• CPC Class Codes: H01L 21/47635 After-treatment of these layers
• CPC Class Codes: H01L 27/1225 with semiconductor materials not belonging to the group IV of the periodic table, e.g. InGaZnO
• CPC Class Codes: H01L 29/0692 Surface layout
• CPC Class Codes: H01L 29/1033 with insulated gate, e.g. characterised by the length, the width, the geometric contour or the doping structure with channel and gate aligned in the lengthwise direction H01L29/42376; with buried channel H01L29/7838
• CPC Class Codes: H01L 29/24 including, apart from doping materials or other impurities, only semiconductor materials not provided for in groups H01L29/16, H01L29/18, H01L29/20, H01L29/22 including organic materials H10K99/00
• CPC Class Codes: H01L 29/263 Amorphous materials
• CPC Class Codes: H01L 29/42364 characterised by the insulating layer, e.g. thickness or uniformity H01L29/42324 and H01L29/4234 take precedence
• 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 29/495 the conductor material next to the insulator being a simple metal, e.g. W, Mo H01L29/4908, H01L29/4983 take precedence
• CPC Class Codes: H01L 29/513 the variation being perpendicular to the channel plane
• CPC Class Codes: H01L 29/518 the insulating material containing nitrogen, e.g. nitride, oxynitride, nitrogen-doped material
• CPC Class Codes: H01L 29/66742 Thin film unipolar transistors
• 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 29/78618 : characterised by the drain or the source properties, e.g. the doping structure, the composition, the sectional shape or the contact structure silicide contacts, electrodes in general H01L29/458
• CPC Class Codes: H01L 29/78633 : with a light shield
• 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 29/78693 : the semiconducting oxide being amorphous
• 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

Abstract

To provide a method by which a semiconductor device including a thin film transistor with excellent electric characteristics and high reliability is manufactured with a small number of steps. After a channel protective layer is formed over an oxide semiconductor film containing In, Ga, and Zn, a film having n-type conductivity and a conductive film are formed, and a resist mask is formed over the conductive film. The conductive film, the film having n-type conductivity, and the oxide semiconductor film containing In, Ga, and Zn are etched using the channel protective layer and gate insulating films as etching stoppers with the resist mask, so that source and drain electrode layers, a buffer layer, and a semiconductor layer are formed.

Claims

1. A method for manufacturing a semiconductor device comprising:

forming a gate electrode layer over a substrate;

forming a gate insulating film comprising silicon oxide over the gate electrode layer;

forming an oxide semiconductor film containing indium and zinc over the gate insulating film;

forming a second insulating film comprising silicon oxide over the oxide semiconductor film;

forming a channel protective layer over a channel formation region of the oxide semiconductor film by selectively etching the second insulating film;

forming a film having n-type conductivity over the oxide semiconductor film;

forming a conductive film over the film having n-type conductivity;

forming a resist mask over the conductive film; and

etching the conductive film, the film having n-type conductivity, and the oxide semiconductor film using the resist mask formed over the conductive film formed over the film having n-type conductivity formed over the channel protective layer to form source and drain electrode layers and a semiconductor layer,

wherein each of the gate insulating film, the oxide semiconductor film and the second insulating film is formed by sputtering in an atmosphere containing oxygen at 90% or more.

2. A method for manufacturing a semiconductor device according to claim 1, wherein the gate insulating film and the channel protective layer serve as etching stoppers.

3. A method for manufacturing a semiconductor device according to claim 1, wherein the gate electrode layer comprises a stack of aluminum and a refractory metal, the refractory metal is selected from the group consisting of titanium, molybdenum and chromium.

4. A method for manufacturing a semiconductor device according to claim 1, wherein the gate insulating film comprises a material selected from the group consisting of silicon oxide, aluminum oxide, magnesium oxide, aluminum nitride, yttrium oxide, hafnium oxide, silicon nitride, silicon oxynitride and silicon nitride oxide.

5. A method for manufacturing a semiconductor device according to claim 1, wherein the gate insulating film, the oxide semiconductor film and the channel protective layer are formed in an atmosphere containing oxygen at 90% or more.

6. A method for manufacturing a semiconductor device according to claim 1, wherein the film having n-type conductivity comprises a material selected from the group consisting of a metal oxide having n-type conductivity and an oxide semiconductor having n-type conductivity and containing indium, gallium, and zinc.

7. A method for manufacturing a semiconductor device according to claim 1, wherein the film having n-type conductivity comprises a metal oxide having n-type conductivity selected from the group consisting of titanium oxide, molybdenum oxide, zinc oxide, indium oxide, tungsten oxide, magnesium oxide, calcium oxide and tin oxide.

8. A method for manufacturing a semiconductor device according to claim 1, wherein the film having n-type conductivity comprises an oxide semiconductor containing indium, gallium, and zinc and including an impurity element imparting n-type conductivity selected from the group consisting of magnesium, aluminum, titanium, scandium, yttrium, zirconium, hafnium, boron, thallium, germanium, tin and lead.

9. A method for manufacturing a semiconductor device according to claim 1, wherein at least one of a source region and a drain region is provided in the film having n-type conductivity.

10. A method for manufacturing a semiconductor device according to claim 1, wherein the semiconductor device is selected from the group consisting of an electronic book reader, a television set, a digital photo frame and a mobile phone.

11. The method according to claim 1, wherein the gate insulating film, the oxide semiconductor film and the second insulating film are successively formed without exposing the substrate to the air.

12. The method according to claim 1, wherein the oxide semiconductor film includes gallium.

13. A method for manufacturing a semiconductor device according to claim 1, further comprising the step of performing a plasma treatment to the oxide semiconductor film in an oxygen containing atmosphere.

14. A method for manufacturing a semiconductor device according to claim 13, wherein the oxygen containing atmosphere includes a gas selected from the group consisting of O₂ and N₂O.

15. A method for manufacturing a semiconductor device according to claim 1, wherein the gate insulating film, the oxide semiconductor film and the second insulating film are successively formed.

16. A method for manufacturing a semiconductor device according to claim 1, wherein the channel protective layer contains excessive oxygen.

17. A method for manufacturing a semiconductor device comprising:

forming a gate electrode layer over a substrate;

forming a gate insulating film over the gate electrode layer;

forming an oxide semiconductor film containing indium and zinc over the gate insulating film;

forming a second insulating film comprising silicon oxide over the oxide semiconductor film;

forming a channel protective layer over a channel formation region of the oxide semiconductor film by selectively etching the second insulating film;

forming a conductive film over the oxide semiconductor film;

forming a resist mask over the conductive film; and

etching the conductive film and the oxide semiconductor film using the resist mask formed over the conductive film to form source and drain electrode layers and a semiconductor layer,

wherein each of the gate insulating film, the oxide semiconductor film and the second insulating film is formed by sputtering in an atmosphere containing oxygen at 90% or more.

18. The method according to claim 17, wherein the gate insulating film, the oxide semiconductor film and the second insulating film are successively formed without exposing the substrate to the air.

19. The method according to claim 17, wherein the oxide semiconductor film includes gallium.

20. The method according to claim 17, further comprising the step of:

forming a film having n-type conductivity over the oxide semiconductor film prior to the formation of the conductive film.

21. A method for manufacturing a semiconductor device according to claim 17, further comprising the step of performing a plasma treatment to the oxide semiconductor film in an oxygen containing atmosphere.

22. A method for manufacturing a semiconductor device according to claim 21, wherein the oxygen containing atmosphere includes a gas selected from the group consisting of O₂ and N₂O.

23. A method for manufacturing a semiconductor device according to claim 17, wherein the gate insulating film, the oxide semiconductor film and the second insulating film are successively formed.

24. A method for manufacturing a semiconductor device according to claim 17, wherein the channel protective layer contains excessive oxygen.

25. A method for manufacturing a semiconductor device according to claim 17, wherein the gate insulating film comprises silicon oxide.

26. A method for manufacturing a semiconductor device comprising:

forming a gate electrode layer over a substrate;

forming a gate insulating film over the gate electrode layer;

forming an oxide semiconductor film containing indium, zinc and excessive oxygen over the gate insulating film;

forming a second insulating film comprising silicon oxide over the oxide semiconductor film;

forming a channel protective layer over a channel formation region of the oxide semiconductor film by selectively etching the second insulating film;

forming a conductive film over the oxide semiconductor film;

forming a resist mask over the conductive film; and

etching the conductive film and the oxide semiconductor film using the resist mask formed over the conductive film to form source and drain electrode layers and a semiconductor layer.

27. The method according to claim 26, wherein the gate insulating film, the oxide semiconductor film and the second insulating film are successively formed without exposing the substrate to the air.

28. The method according to claim 26, wherein the oxide semiconductor film includes gallium.

29. The method according to claim 26, further comprising the step of:

forming a film having n-type conductivity over the oxide semiconductor film prior to the formation of the conductive film.

30. A method for manufacturing a semiconductor device according to claim 26, further comprising the step of performing a plasma treatment to the oxide semiconductor film in an oxygen containing atmosphere.

31. A method for manufacturing a semiconductor device according to claim 30, wherein the oxygen containing atmosphere includes a gas selected from the group consisting of O₂ and N₂O.

32. A method for manufacturing a semiconductor device according to claim 26, wherein the gate insulating film, the oxide semiconductor film and the second insulating film are successively formed.

33. A method for manufacturing a semiconductor device according to claim 26, wherein the channel protective layer contains excessive oxygen.

34. A method for manufacturing a semiconductor device comprising:

forming a gate electrode layer over a substrate;

forming a gate insulating film over the gate electrode layer;

forming an oxide semiconductor film containing indium, zinc and excessive oxygen over the gate insulating film;

forming a second insulating film comprising silicon oxide over the oxide semiconductor film;

forming a channel protective layer over a channel formation region of the oxide semiconductor film by selectively etching the second insulating film;

forming a conductive film over the oxide semiconductor film;

forming a resist mask over the conductive film; and

etching the conductive film and the oxide semiconductor film using the resist mask formed over the conductive film to form source and drain electrode layers and a semiconductor layer,

wherein the gate insulating film contains excessive oxygen and a material selected from the group consisting of silicon oxynitride and silicon nitride oxide.

35. The method according to claim 34, wherein the gate insulating film, the oxide semiconductor film and the second insulating film are successively formed without exposing the substrate to the air.

36. The method according to claim 34, wherein the oxide semiconductor film includes gallium.

37. The method according to claim 34, further comprising the step of:

forming a film having n-type conductivity over the oxide semiconductor film prior to the formation of the conductive film.

38. A method for manufacturing a semiconductor device according to claim 34, further comprising the step of performing a plasma treatment to the oxide semiconductor film in an oxygen containing atmosphere.

39. A method for manufacturing a semiconductor device according to claim 38, wherein the oxygen containing atmosphere includes a gas selected from the group consisting of O₂ and N₂O.

40. A method for manufacturing a semiconductor device according to claim 34, wherein the gate insulating film, the oxide semiconductor film and the second insulating film are successively formed.

41. A method for manufacturing a semiconductor device according to claim 34, wherein the channel protective layer contains excessive oxygen.