METHOD FOR MANUFACTURING OXIDE SEMICONDUCTOR FILM AND METHOD FOR MANUFACTURING SEMICONDUCTOR DEVICE

• US 20110070693A1
• Filed: 09/23/2010
• Published: 03/24/2011
• Est. Priority Date: 09/24/2009
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: MIYANAGA, Akiharu, KOEZUKA, Junichi, YAMAZAKI, Shunpei, IMOTO, Yuki, SAKAKURA, Masayuki, SAKATA, Junichiro, MARUYAMA, Tetsunori
• Granted Patent: US 8,748,223 B2
• Time in Patent Office: Days
• US Class Current: 438/104
• CPC Class Codes: C23C 14/086 of zinc, germanium, cadmium, indium, tin, thallium or bismuth
• CPC Class Codes: H01L 21/02422 Non-crystalline insulating materials, e.g. glass, polymers
• 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 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

An object is to provide an oxide semiconductor having stable electric characteristics and a semiconductor device including the oxide semiconductor. A manufacturing method of a semiconductor film by a sputtering method includes the steps of holding a substrate in a treatment chamber which is kept in a reduced-pressure state; heating the substrate at lower than 400° C.; introducing a sputtering gas from which hydrogen and moisture are removed in the state where remaining moisture in the treatment chamber is removed; and forming an oxide semiconductor film over the substrate with use of a metal oxide which is provided in the treatment chamber as a target. When the oxide semiconductor film is formed, remaining moisture in a reaction atmosphere is removed; thus, the concentration of hydrogen and the concentration of hydride in the oxide semiconductor film can be reduced. Thus, the oxide semiconductor film can be stabilized.

Claims

1. A method for manufacturing an oxide semiconductor film, comprising the steps of:

heating a substrate at lower than 400°

C.;

introducing a sputtering gas from which hydrogen and moisture are removed into a treatment chamber while moisture remaining in the treatment chamber is removed; and

forming an oxide semiconductor film over the substrate by a metal oxide as a target,

wherein the substrate is held in the treatment chamber kept in a reduced-pressure state.

2. The method for manufacturing an oxide semiconductor film according to claim 1, wherein the moisture remaining in the treatment chamber is removed by evacuation with use of a cryopump evacuating the treatment chamber.

3. The method for manufacturing an oxide semiconductor film according to claim 1, wherein the target contains zinc oxide as a main component.

4. The method for manufacturing an oxide semiconductor film according to claim 1, wherein the metal oxide as the target is a metal oxide containing indium, gallium, and zinc.

5. A method for manufacturing an oxide semiconductor film, comprising the steps of:

heating a substrate at lower than 400°

C.;

introducing a sputtering gas from which hydrogen and moisture are removed into a treatment chamber while moisture remaining in the treatment chamber is removed; and

forming an oxide semiconductor film over the substrate by a metal oxide as a target,

wherein the substrate is held in the treatment chamber kept in a reduced-pressure state, and

wherein a concentration of hydrogen in the oxide semiconductor film is lower than or equal to 5×

10¹⁹/cm³.

6. The method for manufacturing an oxide semiconductor film according to claim 5, wherein the moisture remaining in the treatment chamber is removed by evacuation with use of a cryopump evacuating the treatment chamber.

7. The method for manufacturing an oxide semiconductor film according to claim 5, wherein the target contains zinc oxide as a main component.

8. The method for manufacturing an oxide semiconductor film according to claim 5, wherein the metal oxide as the target is a metal oxide containing indium, gallium, and zinc.

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

introducing a substrate over which a gate electrode and a gate insulating film are formed into a first treatment chamber;

heating the substrate at lower than 400°

C.;

introducing a sputtering gas from which hydrogen and moisture are removed while moisture remaining in the first treatment chamber is removed;

forming an oxide semiconductor film over the gate electrode with the gate insulating film therebetween by a metal oxide which is provided in the first treatment chamber and contains at least zinc oxide as a target;

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

introducing the substrate into a second treatment chamber;

keeping a temperature of the substrate lower than 100°

C.;

introducing a sputtering gas including oxygen from which hydrogen and moisture are removed while moisture remaining in the second treatment chamber is removed;

forming a silicon oxide film including a defect over the substrate by a silicon semiconductor target which is provided in the second treatment chamber;

introducing the substrate over which the silicon oxide film is formed into a third treatment chamber;

heating the substrate at 200°

C. to 400°

C. to diffuse hydrogen or moisture included in the oxide semiconductor film into the silicon oxide film including the defect; and

forming a silicon nitride film over the silicon oxide film.

10. The method for manufacturing a semiconductor device according to claim 9, wherein the moisture remaining in the first treatment chamber is removed by evacuation with use of a cryopump evacuating the first treatment chamber.

11. The method for manufacturing a semiconductor device according to claim 9, wherein the moisture remaining in the first treatment chamber and the moisture remaining in the second treatment chamber are removed by evacuation with use of a cryopump evacuating the first treatment chamber and the second treatment chamber.

12. The method for manufacturing a semiconductor device according to claim 9, wherein the metal oxide as the target contains zinc oxide as a main component.

13. The method for manufacturing a semiconductor device according to claim 9, wherein the metal oxide as the target is a metal oxide containing indium, gallium, and zinc.