Semiconductor device and method for manufacturing the same

• US 8,546,181 B2
• Filed: 09/25/2012
• Issued: 10/01/2013
• Est. Priority Date: 09/29/2011
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Yamazaki, Shunpei
• Primary Examiner(s): Lee, Calvin
• Assistant Examiner(s): STOWE, SCOTT C
• Application Number:
  US13/626,146
• Publication Number:
  US 20130082252A1
• Time in Patent Office: 371 Days
• Field of Search: 257/43, 257/E29.296, 438/104, 438/158
• US Class Current: 438/104
• 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 29/6675 Amorphous silicon or polysilicon 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 29/7869 having a semiconductor body comprising an oxide semiconductor material, e.g. zinc oxide, copper aluminium oxide, cadmium stannate

Abstract

A highly reliable semiconductor device is provided. A semiconductor device is manufactured at a high yield, so that high productivity is achieved. In a semiconductor device including a transistor in which a gate electrode layer, a gate insulating film, an oxide semiconductor film containing indium, and an insulating layer provided on and in contact with the oxide semiconductor film so as to overlap with the gate electrode layer are stacked and a source electrode layer and a drain electrode layer are provided in contact with the oxide semiconductor film and the insulating layer, the chlorine concentration and the indium concentration on a surface of the insulating layer are lower than or equal to 1×10¹⁹/cm³ and lower than or equal to 2×10¹⁹/cm³, respectively.

Claims

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

forming a gate electrode layer over an insulating surface;

forming a gate insulating film over the gate electrode layer;

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

forming an insulating layer on and in contact with the oxide semiconductor film, the insulating layer overlapping with the gate electrode layer;

forming a conductive film over and in contact with the oxide semiconductor film and the insulating layer;

etching the conductive film with a gas containing chlorine to form a source electrode layer and a drain electrode layer; and

removing residues on the oxide semiconductor film and the insulating layer,

wherein the residues are formed by a reaction between the gas and the oxide semiconductor film.

2. The method according to claim 1, wherein a part of the residues are scattered and attached with the insulating layer before the removing step.

3. The method according to claim 1, wherein a cleaning treatment using a dilute hydrofluoric acid solution is performed as the removing step.

4. The method according to claim 1, wherein a plasma treatment using a rare gas is performed as the removing step.

5. The method according to claim 1, wherein each of the residues comprises a compound containing indium and chlorine.

6. The method according to claim 1, wherein a part of the residues are scattered and attached with a surface of the insulating layer.

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

forming a gate electrode layer over an insulating surface;

forming a gate insulating film over the gate electrode layer;

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

forming an insulating layer on and in contact with the oxide semiconductor film, the insulating layer overlapping with the gate electrode layer;

forming a conductive film over and in contact with the oxide semiconductor film and the insulating layer;

etching the conductive film with a gas containing chlorine to form a source electrode layer and a drain electrode layer; and

removing residues on a surface of the insulating layer and a vicinity of the insulating layer,

wherein the residues are formed by a reaction between the gas and the oxide semiconductor film.

8. The method according to claim 7, wherein a part of the residues are scattered and attached with the insulating layer before the removing step.

9. The method according to claim 7, wherein a cleaning treatment using a dilute hydrofluoric acid solution is performed as the removing step.

10. The method according to claim 7, wherein a plasma treatment using a rare gas is performed as the removing step.

11. The method according to claim 7, wherein each of the residues comprises a compound containing indium and chlorine.

12. The method according to claim 7, wherein a part of the residues are scattered and attached with the surface of the insulating layer and the vicinity of the insulating layer.