Method of manufacturing semiconductor device

• US 8,241,949 B2
• Filed: 07/13/2010
• Issued: 08/14/2012
• Est. Priority Date: 07/17/2009
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Miyanaga, Akiharu
• Primary Examiner(s): Ghyka, Alexander
• Assistant Examiner(s): ISAAC, STANETTA D
• Application Number:
  US12/835,115
• Publication Number:
  US 20110014745A1
• Time in Patent Office: 763 Days
• Field of Search: 438/104, 257/E21.461
• US Class Current: 438/104
• 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 29/04 characterised by their crystalline structure, e.g. polycrystalline, cubic or particular orientation of crystalline planes characterised by physical imperfections H01L29/30
• 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 29/7869 having a semiconductor body comprising an oxide semiconductor material, e.g. zinc oxide, copper aluminium oxide, cadmium stannate

Abstract

An object is to provide a method for manufacturing a highly reliable semiconductor device including a transistor with stable electric characteristics. A method for manufacturing a semiconductor device includes the steps of: forming a gate electrode over a substrate having an insulating surface; forming a gate insulating film over the gate electrode; forming an oxide semiconductor film over the gate insulating film; irradiating the oxide semiconductor film with an electromagnetic wave such as a microwave or a high frequency; forming a source electrode and a drain electrode over the oxide semiconductor film irradiated with the electromagnetic wave; and forming an oxide insulating film, which is in contact with part of the oxide semiconductor film, over the gate insulating film, the oxide semiconductor film, the source electrode, and the drain electrode.

Claims

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

forming a first oxide semiconductor film over a substrate having an insulating surface; and

irradiating the first oxide semiconductor film with a microwave having a frequency greater than or equal to 300 MHz and less than or equal to 3 THz under an inert gas atmosphere or reduced pressure, or in air where a dew point under atmospheric pressure is −

60°

C. or lower to give energy to a polar molecule included in the first oxide semiconductor film, so that the polar molecule is evaporated.

2. A method according to claim 1, wherein the inert gas atmosphere is a nitrogen atmosphere or a rare gas atmosphere.

3. A method according to claim 1, further comprising introducing oxygen into the first oxide semiconductor film after the irradiating step.

4. A method according to claim 3, wherein oxygen is introduced into the first oxide semiconductor film by heat treatment under an oxygen atmosphere.

5. A method according to claim 3, wherein after the introducing step, a second oxide semiconductor film is formed in contact with the first oxide semiconductor film.

6. A method according to claim 1, wherein the first oxide semiconductor film comprises In, Ga, Zn and O.

7. A method according to claim 1, wherein the frequency of the microwave is greater than or equal to 300 MHz and less than or equal to 300 GHz.

8. A method according to claim 1, wherein the frequency of the microwave is 915 MHz or 2.45 GHz.

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

forming a first oxide semiconductor film over a substrate having an insulating surface; and

irradiating the first oxide semiconductor film with a high frequency wave having a frequency greater than or equal to 1 MHz and less than or equal to 300 MHz under an inert gas atmosphere or reduced pressure, or in air where a dew point under atmospheric pressure is −

60°

C. or lower to give energy to a polar molecule included in the first oxide semiconductor film, so that the polar molecule is evaporated.

10. A method according to claim 9, wherein the inert gas atmosphere is a nitrogen atmosphere or a rare gas atmosphere.

11. A method according to claim 9, further comprising introducing oxygen into the first oxide semiconductor film after the irradiating step.

12. A method according to claim 11, wherein oxygen is introduced into the first oxide semiconductor film by heat treatment under an oxygen atmosphere.

13. A method according to claim 11, wherein after the introducing step, a second oxide semiconductor film is formed in contact with the first oxide semiconductor film.

14. A method according to claim 9, wherein the first oxide semiconductor film comprises In, Ga, Zn and O.

15. A method according to claim 9, wherein the frequency of the high frequency wave is greater than or equal to 4 MHz and less than or equal to 80 MHz.

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

forming a gate electrode over a substrate having an insulating surface;

forming a gate insulating film over the gate electrode;

forming an oxide semiconductor film over the gate insulating film;

irradiating the oxide semiconductor film with a microwave having a frequency greater than or equal to 300 MHz and less than or equal to 3 THz;

forming a source electrode and a drain electrode over the oxide semiconductor film irradiated with the microwave wave; and

forming an oxide insulating film, which is in contact with part of the oxide semiconductor film, over the gate insulating film, the oxide semiconductor film, the source electrode, and the drain electrode.

17. A method according to claim 16, wherein the irradiating step is performed while performing heat treatment on the oxide semiconductor film.

18. A method according to claim 17, wherein the heat treatment is performed at higher than or equal to 100°

C. and lower than 350°

C.

19. A method according to claim 16, wherein the irradiating step is performed before forming the source electrode and the drain electrode.

20. A method according to claim 16, wherein the irradiating step is performed after forming the source electrode and the drain electrode.

21. A method according to claim 16, wherein the irradiating step is performed under a nitrogen atmosphere, a rare gas atmosphere or reduced pressure.

22. A method according to claim 16, wherein the oxide semiconductor film comprises In, Ga, Zn and O.

23. A method according to claim 16, wherein the frequency of the microwave is greater than or equal to 300 MHz and less than or equal to 300 GHz.

24. A method according to claim 16, wherein the frequency of the microwave is 915 MHz or 2.45 GHz.

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

forming a gate electrode over a substrate having an insulating surface;

forming a gate insulating film over the gate electrode;

forming an oxide semiconductor film over the gate insulating film;

irradiating the oxide semiconductor film with a high frequency wave having a frequency greater than or equal to 1 MHz and less than or equal to 300 MHz;

forming a source electrode and a drain electrode over the oxide semiconductor film irradiated with the high frequency wave; and

forming an oxide insulating film, which is in contact with part of the oxide semiconductor film, over the gate insulating film, the oxide semiconductor film, the source electrode, and the drain electrode.

26. A method according to claim 25, wherein the irradiating step is performed while performing heat treatment on the oxide semiconductor film.

27. A method according to claim 26, wherein the heat treatment is performed at higher than or equal to 100°

C. and lower than 350°

C.

28. A method according to claim 25, wherein the irradiating step is performed before forming the source electrode and the drain electrode.

29. A method according to claim 25, wherein the irradiating step is performed after forming the source electrode and the drain electrode.

30. A method according to claim 25, wherein the irradiating step is performed under a nitrogen atmosphere, a rare gas atmosphere or reduced pressure.

31. A method according to claim 25, wherein the oxide semiconductor film comprises In, Ga, Zn and O.

32. A method according to claim 25, wherein the frequency of the high frequency wave is greater than or equal to 4 MHz and less than or equal to 80 MHz.