Method for manufacturing semiconductor device

• US 8,809,115 B2
• Filed: 08/11/2011
• Issued: 08/19/2014
• Est. Priority Date: 09/01/2008
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Akimoto, Kengo, Tsubuku, Masashi
• Primary Examiner(s): Abdelaziez, Yasser A
• Application Number:
  US13/207,449
• Publication Number:
  US 20110291089A1
• Time in Patent Office: 1,104 Days
• Field of Search: None
• US Class Current: 438/104
• 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 21/324 Thermal treatment for modifying the properties of semiconductor bodies, e.g. annealing, sintering H01L21/20 - H01L21/288 and H01L21/302 - H01L21/322 take precedence
• CPC Class Codes: H01L 21/447 involving the application of pressure, e.g. thermo-compression bonding
• 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 27/127 with a particular formation, treatment or patterning of the active layer specially adapted to the circuit arrangement
• CPC Class Codes: H01L 29/66742 Thin film unipolar transistors
• 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 method for manufacturing a thin film transistor in which contact resistance between an oxide semiconductor layer and source and drain electrode layers is small, the surfaces of the source and drain electrode layers are subjected to sputtering treatment with plasma and an oxide semiconductor layer containing In, Ga, and Zn is formed successively over the source and drain electrode layers without exposure of the source and drain electrode layers to air.

Claims

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

forming an oxide semiconductor film comprising indium and zinc by sputtering over a substrate; and

heating the oxide semiconductor film to increase crystallinity of the oxide semiconductor film,

wherein the oxide semiconductor film after the heating exhibits a peak in a range of 30°

≦

2θ

≦

35°

when the oxide semiconductor film is measured by an X-ray diffraction method.

2. The method according to claim 1 wherein the oxide semiconductor film further comprises gallium.

3. The method according to claim 1 wherein the heating is performed at a temperature of 700°

C. or higher.

4. The method according to claim 1 further comprising a step of treating the oxide semiconductor film with a plasma containing oxygen.

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

performing a sputtering treatment on a surface of an insulating film;

after performing the sputtering treatment, forming an oxide semiconductor film on the insulating film successively without exposure of the insulating film to air, the oxide semiconductor film comprising indium and zinc; and

heating the oxide semiconductor film to increase crystallinity of the oxide semiconductor film,

wherein the oxide semiconductor film after the heating exhibits a peak in a range of 30°

≦

2θ

≦

35°

when the oxide semiconductor film is measured by an X-ray diffraction method.

6. The method according to claim 5, further comprising a step of:

forming a source electrode and a drain electrode over the insulating film,

wherein the sputtering treatment is performed on surfaces of the source electrode and the drain electrode after forming the source electrode and the drain electrode.

7. The method according to claim 6, wherein the oxide semiconductor film is formed over the source electrode and the drain electrode.

8. The method for manufacturing a semiconductor device according to claim 5, wherein the oxide semiconductor film further comprises gallium.

9. The method according to claim 5, wherein the sputtering treatment is performed in an inert gas atmosphere.

10. The method according to claim 9, wherein the inert gas atmosphere comprises rare gas.

11. The method according to claim 5 wherein the heating is performed at a temperature of 700°

C. or higher.

12. The method according to claim 5 further comprising a step of treating the oxide semiconductor film with a plasma containing oxygen.

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

etching a surface of an insulating film;

after etching the surface of the insulating film, forming an oxide semiconductor film on the insulating film successively without exposure of the insulating film to air, the oxide semiconductor film comprising indium and zinc; and

heating the oxide semiconductor film to increase crystallinity of the oxide semiconductor film,

wherein the oxide semiconductor film after the heating exhibits a peak in a range of 30°

≦

2θ

≦

35°

when the oxide semiconductor film is measured by an X-ray diffraction method.

14. The method according to claim 13 wherein the oxide semiconductor film further comprises gallium.

15. The method according to claim 13 wherein the heating is performed at a temperature of 700°

C. or higher.

16. The method according to claim 13 further comprising a step of treating the oxide semiconductor film with a plasma containing oxygen.

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

performing a sputtering treatment on a surface of an insulating film; and

after performing the sputtering treatment, forming an oxide semiconductor film over the insulating film successively without exposure of the insulating film to air.

18. The method for manufacturing a semiconductor device according to claim 17, further comprising a step of:

forming a source electrode and a drain electrode over the insulating film,

wherein the sputtering treatment is performed on surfaces of the source electrode and the drain electrode after forming the source electrode and the drain electrode.

19. The method for manufacturing a semiconductor device according to claim 18, wherein the oxide semiconductor film is formed over the source electrode and the drain electrode.

20. The method according to claim 18, further comprising a step of:

forming a gate electrode over a substrate,

wherein the insulating film is formed over the gate electrode.

21. The method according to claim 17, further comprising a step of forming a gate electrode over the oxide semiconductor film.

22. The method according to claim 17, wherein the oxide semiconductor film comprises indium, gallium, and zinc.

23. The method according to claim 17, wherein the sputtering treatment is performed in an inert gas atmosphere.

24. The method according to claim 23, wherein the inert gas atmosphere comprises rare gas.

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

applying a voltage to gas containing an inert gas for producing plasma of the gas;

exposing a surface of an insulating film to the plasma so that the surface of the insulating film is etched by the plasma; and

after exposing the surface of the insulating film to the plasma, forming an oxide semiconductor film over the insulating film successively without exposure of the insulating film to air.

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

etching a surface of an insulating film; and

after etching the surface of the insulating film, forming an oxide semiconductor film over the insulating film successively without exposure of the insulating film to air.

27. A semiconductor device comprising:

an oxide semiconductor film over a substrate, the oxide semiconductor film comprising indium and zinc,

wherein the oxide semiconductor film has a crystallinity and exhibits a peak in a range of 30°

≦

2θ

≦

35°

when the oxide semiconductor film is measured by an X-ray diffraction method.

28. The semiconductor device according to claim 27 wherein the oxide semiconductor film further comprises gallium.

29. The semiconductor device according to claim 27 further comprising;

an insulating film over the substrate; and

a source electrode on the insulating film;

a drain electrode on the insulating film,

wherein the oxide semiconductor film is formed on the source electrode and the drain electrode and is in contact with a portion of the insulating film between the source electrode and the drain electrode, and

wherein a thickness of the insulating film just below the source electrode and the drain electrode is greater than a thickness of the portion of the insulating film between the source electrode and the drain electrode.

30. The semiconductor device according to claim 29, further comprising a gate electrode over the substrate, wherein the insulating film is provided over the gate electrode.