Manufacturing method of oxide semiconductor film and manufacturing method of transistor

• US 8,703,531 B2
• Filed: 02/25/2011
• Issued: 04/22/2014
• Est. Priority Date: 03/05/2010
• Status: Expired due to Fees

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Honda, Tatsuya, Omata, Takatsugu, Nonaka, Yusuke
• Primary Examiner(s): BOOTH, RICHARD A
• Application Number:
  US13/034,725
• Publication Number:
  US 20110217815A1
• Time in Patent Office: 1,152 Days
• Field of Search: 438151-166, 438/104, 257/E21.561
• US Class Current: 438/104
• CPC Class Codes: H01L 21/0237 Materials
• CPC Class Codes: H01L 21/02422 Non-crystalline insulating materials, e.g. glass, polymers
• 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 21/02614 Transformation of metal, e.g. oxidation, nitridation
• CPC Class Codes: H01L 21/02631 Physical deposition at reduced pressure, e.g. MBE, sputtering, evaporation
• CPC Class Codes: H01L 21/02667 Crystallisation or recrystallisation of non-monocrystalline semiconductor materials, e.g. regrowth
• 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 manufacturing method of an oxide semiconductor film with high crystallinity. Another object is to provide a manufacturing method of a transistor with high field effect mobility. In a manufacturing method of an oxide semiconductor film, an oxide semiconductor film is formed over a substrate in an atmosphere in which oxygen is purposely not contained, and then the oxide semiconductor film is crystallized by a heat treatment in an atmosphere containing oxygen.

Claims

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

forming a first oxide semiconductor film over a substrate;

crystallizing the first oxide semiconductor film by performing a first heat treatment;

forming a second oxide semiconductor film over the crystallized first oxide semiconductor film in an atmosphere which the second oxide semiconductor film formed therein is oxygen deficient; and

crystallizing the second oxide semiconductor film by performing a second heat treatment in an atmosphere containing oxygen.

2. The manufacturing method of a semiconductor device according to claim 1, wherein the first oxide semiconductor film is formed in an atmosphere in which oxygen is purposely not contained.

3. The manufacturing method of a semiconductor device according to claim 1, wherein the first oxide semiconductor film that is crystallized in the first heat treatment is used as a seed crystal by the second oxide semiconductor film that is to be crystallized in the second heat treatment.

4. The manufacturing method of a semiconductor device according to claim 1, wherein at least one of the first oxide semiconductor film and the second oxide semiconductor film is selected from an In—

Sn—

Ga—

Zn—

O-based oxide semiconductor, an In—

Ga—

Zn—

O-based oxide semiconductor, an In—

Sn—

Zn—

O-based oxide semiconductor, an In—

Al—

Zn—

O-based oxide semiconductor, an Sn—

Ga—

Zn—

O-based oxide semiconductor, an Al—

Ga—

Zn—

O-based oxide semiconductor, an Sn—

Al—

Zn—

O-based oxide semiconductor, an In—

Zn—

O-based oxide semiconductor, an Sn—

Zn—

O-based oxide semiconductor, Al—

Zn—

O-based oxide semiconductor, an In—

O-based oxide semiconductor, and an Sn—

O-based oxide semiconductor, an Zn—

O-based oxide semiconductor.

5. The manufacturing method of a semiconductor device according to claim 1, wherein the first oxide semiconductor film and the second oxide semiconductor film have a c-axis orientation with respect to a surface of the substrate.

6. The manufacturing method of a semiconductor device according to claim 1, wherein a carrier density of the first oxide semiconductor film and the second oxide semiconductor film is less than 1×

10¹⁴/cm³.

7. The manufacturing method of a semiconductor device according to claim 1, wherein at least one of the first oxide semiconductor film and the second oxide semiconductor film is formed while the substrate is heated.

8. The manufacturing method of a semiconductor device according to claim 1, wherein the atmosphere which the second oxide semiconductor film formed therein is oxygen deficient is an atmosphere of nitrogen gas, helium gas, neon gas, argon gas, xenon gas, or krypton gas.

9. The manufacturing method of a semiconductor device according to claim 1, wherein the second oxide semiconductor film is formed by a sputtering method under a condition in which oxygen gas is not supplied.

10. A manufacturing method of a transistor, comprising the steps of:

forming a gate electrode over a substrate;

forming a gate insulating film over the gate electrode;

forming a first oxide semiconductor film over the gate insulating film;

crystallizing the first oxide semiconductor film by performing a first heat treatment;

forming a second oxide semiconductor film over the crystallized first oxide semiconductor film in an atmosphere which the second oxide semiconductor film formed therein is oxygen deficient;

crystallizing the second oxide semiconductor film by performing a second heat treatment in an atmosphere containing oxygen;

forming a source electrode and a drain electrode over the crystallized second oxide semiconductor film;

forming an insulating film containing an oxygen atom over the crystallized second oxide semiconductor film, the source electrode and the drain electrode; and

oxidizing the crystallized first oxide semiconductor film and the crystallized second oxide semiconductor film by performing a third heat treatment.

11. The manufacturing method of a transistor according to claim 10, wherein the first oxide semiconductor film is formed in an atmosphere in which oxygen is purposely not contained.

12. The manufacturing method of a transistor according to claim 10, wherein the first oxide semiconductor film that is crystallized by the first heat treatment is used as a seed crystal by the second oxide semiconductor film that is to be crystallized by the second heat treatment.

13. The manufacturing method of a transistor according to claim 10, wherein at least one of the first oxide semiconductor film and the second oxide semiconductor film is selected from an In—

Sn—

Ga—

Zn—

O-based oxide semiconductor, an In—

Ga—

Zn—

O-based oxide semiconductor, an In—

Sn—

Zn—

O-based oxide semiconductor, an In—

Al—

Zn—

O-based oxide semiconductor, an Sn—

Ga—

Zn—

O-based oxide semiconductor, an Al—

Ga—

Zn—

O-based oxide semiconductor, an Sn—

Al—

Zn—

O-based oxide semiconductor, an In—

Zn—

O-based oxide semiconductor, an Sn—

Zn—

O-based oxide semiconductor, Al—

Zn—

O-based oxide semiconductor, an In—

O-based oxide semiconductor, and an Sn—

O-based oxide semiconductor, an Zn—

O-based oxide semiconductor.

14. The manufacturing method of a transistor according to claim 10, wherein the first oxide semiconductor film and the second oxide semiconductor film have a c-axis orientation with respect to a surface of the substrate.

15. The manufacturing method of a transistor according to claim 10, wherein a carrier density of the first oxide semiconductor film and the second oxide semiconductor film is less than 1×

10¹⁴/cm³.

16. The manufacturing method of a transistor according to claim 10, wherein at least one of the first oxide semiconductor film and the second oxide semiconductor film is formed while the substrate is heated.

17. The manufacturing method of a transistor according to claim 10, wherein the atmosphere which the second oxide semiconductor film formed therein is oxygen deficient is an atmosphere of nitrogen gas, helium gas, neon gas, argon gas, xenon gas, or krypton gas.

18. The manufacturing method of a transistor according to claim 10, wherein the second oxide semiconductor film is formed by a sputtering method under a condition in which oxygen gas is not supplied.

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

forming a first oxide semiconductor film over a substrate;

performing a first heat treatment to the first oxide semiconductor film in an atmosphere containing oxygen at a temperature of 600 °

C. or more so as to supply oxygen to the first oxide semiconductor film;

forming a second oxide semiconductor film over the first oxide semiconductor film by a sputtering method using an oxide semiconductor target under an inert gas in which oxygen gas is not supplied so that the second oxide semiconductor film has an oxygen deficiency; and

performing a second heat treatment to the second oxide semiconductor film in an atmosphere containing oxygen at a temperature of 600 °

C. or more so as to supply oxygen to the second oxide semiconductor film,

wherein, after the second heating, the second oxide semiconductor film has a c-axis orientation with respect to a surface of the substrate.

20. The manufacturing method of a semiconductor device according to claim 19, wherein the second oxide semiconductor film is selected from an In—

Sn—

Ga—

Zn—

O-based oxide semiconductor, an In—

Ga—

Zn—

O-based oxide semiconductor, an In—

Sn—

Zn—

O-based oxide semiconductor, an In—

Al—

Zn—

O-based oxide semiconductor, an Sn—

Ga—

Zn—

O-based oxide semiconductor, an Al—

Ga—

Zn—

O-based oxide semiconductor, an Sn—

Al—

Zn—

O-based oxide semiconductor, an In—

Zn—

O-based oxide semiconductor, an Sn—

Zn—

O-based oxide semiconductor, Al—

Zn—

O-based oxide semiconductor, an In—

O-based oxide semiconductor, an Sn—

O-based oxide semiconductor, and an Zn—

O-based oxide semiconductor.

21. The manufacturing method of a semiconductor device according to claim 19, wherein a carrier density of the second oxide semiconductor film is less than 1×

10¹⁴/cm³.

22. The manufacturing method of a semiconductor device according to claim 19, wherein the second oxide semiconductor film is formed while the substrate is heated.

23. The manufacturing method of a semiconductor device according to claim 19, wherein the inert gas is any of nitrogen gas, helium gas, neon gas, argon gas, xenon gas, and krypton gas.