Method for manufacturing oxide semiconductor film

• US 10,103,277 B2
• Filed: 07/13/2017
• Issued: 10/16/2018
• Est. Priority Date: 12/03/2010
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Yamazaki, Shunpei, Tsubuku, Masashi, Akimoto, Kengo, Ohara, Hiroki, Honda, Tatsuya, Omata, Takatsugu, Nonaka, Yusuke, Takahashi, Masahiro, Miyanaga, Akiharu
• Primary Examiner(s): Le, Dung
• Application Number:
  US15/648,943
• Publication Number:
  US 20170309754A1
• Time in Patent Office: 460 Days
• CPC Class Codes: H01L 29/045 by their particular orientation of crystalline planes
• 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 29/247 Amorphous materials
• 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

A method comprising a step of forming an oxide semiconductor film over a substrate by a sputtering method while heating the substrate at a temperature of higher than 200° C. and lower than or equal to 400° C. is provided. The oxide semiconductor film comprises a crystalline region and is in a non-single-crystal state. The step of forming the oxide semiconductor film is performed by using a sputtering target comprising indium, gallium, zinc and oxygen and a sputtering gas comprising at least one of a rare gas and oxygen.

Claims

1. A method for manufacturing an oxide semiconductor film comprising a step of:

forming an oxide semiconductor film over a substrate by a sputtering method while heating the substrate at a temperature of higher than 200°

C. and lower than or equal to 400°

C.,

wherein the oxide semiconductor film comprises a crystalline region in which a c-axis is substantially perpendicular to a surface of the oxide semiconductor film,

wherein the oxide semiconductor film is in a non-single-crystal state,

wherein the step of forming the oxide semiconductor film is performed by using a sputtering target comprising indium, gallium, zinc and oxygen, and

wherein the step of forming the oxide semiconductor film is performed by using a sputtering gas comprising at least one of a rare gas and oxygen.

2. The method for manufacturing an oxide semiconductor film according to claim 1,

wherein the step of forming the oxide semiconductor film is performed in a treatment chamber, and

wherein a pressure of the treatment chamber is set to lower than or equal to 0.4 Pa.

3. The method for manufacturing an oxide semiconductor film according to claim 1,

wherein the step of forming the oxide semiconductor film is performed in a treatment chamber, and

wherein a leakage rate of the treatment chamber is set to lower than or equal to 1×

10<sup>−

10</sup> Pa·

m³sec.

4. The method for manufacturing an oxide semiconductor film according to claim 1, wherein the temperature at the step of forming the oxide semiconductor film is higher than or equal to 250°

C. and lower than or equal to 350°

C.

5. The method for manufacturing an oxide semiconductor film according to claim 1, wherein a purity of the sputtering target is set to higher than or equal to 99.99%.

6. The method for manufacturing an oxide semiconductor film according to claim 1, wherein a concentration of lithium in the oxide semiconductor film is 5×

10¹⁵ atoms/cm³ or lower.

7. The method for manufacturing an oxide semiconductor film according to claim 1, wherein a concentration of sodium in the oxide semiconductor film is 5×

10¹⁶ atoms/cm³ or lower.

8. The method for manufacturing an oxide semiconductor film according to claim 1, wherein a concentration of potassium in the oxide semiconductor film is 5×

10¹⁵ atoms/cm³ or lower.

9. The method for manufacturing an oxide semiconductor film according to claim 1, wherein an angle between the c-axis and a normal of the surface of the oxide semiconductor film is greater than or equal to 0°

and less than or equal to 20°

.

10. A method for manufacturing an oxide semiconductor film comprising a step of:

forming an oxide semiconductor film over a substrate by a sputtering method while heating the substrate at a temperature of higher than 200°

C. and lower than or equal to 400°

C.; and

performing a heat treatment after forming the oxide semiconductor film at a temperature higher than the temperature at the step of forming the oxide semiconductor film,

wherein the oxide semiconductor film comprises a crystalline region in which a c-axis is substantially perpendicular to a surface of the oxide semiconductor film,

wherein the oxide semiconductor film is in a non-single-crystal state,

wherein the step of forming the oxide semiconductor film is performed by using a sputtering target comprising indium, gallium, zinc and oxygen, and

wherein the step of forming the oxide semiconductor film is performed by using a sputtering gas comprising at least one of a rare gas and oxygen.

11. The method for manufacturing an oxide semiconductor film according to claim 10,

wherein the step of forming the oxide semiconductor film is performed in a treatment chamber, and

wherein a pressure of the treatment chamber is set to lower than or equal to 0.4 Pa.

12. The method for manufacturing an oxide semiconductor film according to claim 10,

wherein the step of forming the oxide semiconductor film is performed in a treatment chamber, and

wherein a leakage rate of the treatment chamber is set to lower than or equal to 1×

10<sup>−

10</sup> Pa·

m³sec.

13. The method for manufacturing an oxide semiconductor film according to claim 10, wherein the temperature at the step of forming the oxide semiconductor film is higher than or equal to 250°

C. and lower than or equal to 350°

C.

14. The method for manufacturing an oxide semiconductor film according to claim 10, wherein a purity of the sputtering target is set to higher than or equal to 99.99%.

15. The method for manufacturing an oxide semiconductor film according to claim 10, wherein a concentration of lithium in the oxide semiconductor film is 5×

10¹⁵ atoms/cm³ or lower.

16. The method for manufacturing an oxide semiconductor film according to claim 10, wherein a concentration of sodium in the oxide semiconductor film is 5×

10¹⁶ atoms/cm³ or lower.

17. The method for manufacturing an oxide semiconductor film according to claim 10, wherein a concentration of potassium in the oxide semiconductor film is 5×

10¹⁵ atoms/cm³ or lower.

18. The method for manufacturing an oxide semiconductor film according to claim 10, wherein an angle between the c-axis and a normal of the surface of the oxide semiconductor film is greater than or equal to 0°

and less than or equal to 20°

.