Method for manufacturing semiconductor device

• US 8,551,824 B2
• Filed: 02/17/2011
• Issued: 10/08/2013
• Est. Priority Date: 02/26/2010
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Yamazaki, Shunpei, Koezuka, Junichi
• Primary Examiner(s): Ahmadi, Mohsen
• Application Number:
  US13/029,148
• Publication Number:
  US 20110212569A1
• Time in Patent Office: 964 Days
• Field of Search: 257/E21.372, 257/E21.411, 257/E21.476
• US Class Current: 438/149
• CPC Class Codes: G02F 1/134309 characterised by their geometrical arrangement
• CPC Class Codes: G02F 1/13439 characterised by their electrical, optical, physical properties; materials therefor; method of making
• CPC Class Codes: G02F 1/1368 in which the switching element is a three-electrode device G02F1/136277 takes precedence
• CPC Class Codes: G02F 2201/123 pixel
• CPC Class Codes: H01L 21/385 using diffusion into or out of a solid from or into a solid phase, e.g. a doped oxide layer
• 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 27/124 with a particular composition, shape or layout of the wiring layers specially adapted to the circuit arrangement, e.g. scanning lines in LCD pixel circuits wiring structures per se H01L23/52
• CPC Class Codes: H01L 29/41733 for thin film transistors with insulated gate
• CPC Class Codes: H01L 29/4908 for thin film semiconductor, e.g. gate of TFT
• CPC Class Codes: H01L 29/4958 with a multiple layer structure
• CPC Class Codes: H01L 29/4966 the conductor material next to the insulator being a composite material, e.g. organic material, TiN, MoSi2 H01L29/4908, H01L29/4983 take precedence
• CPC Class Codes: H01L 29/513 the variation being perpendicular to the channel plane
• CPC Class Codes: H01L 29/518 the insulating material containing nitrogen, e.g. nitride, oxynitride, nitrogen-doped material
• 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
• 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

In a transistor including an oxide semiconductor layer, an oxide insulating layer is formed so as to be in contact with the oxide semiconductor layer. Then, oxygen is introduced (added) to the oxide semiconductor layer through the oxide insulating layer, and heat treatment is performed. Through these steps of oxygen introduction and heat treatment, impurities such as hydrogen, moisture, a hydroxyl group, or hydride are intentionally removed from the oxide semiconductor layer, so that the oxide semiconductor layer is highly purified.

Claims

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

forming an oxide semiconductor layer;

forming an oxide insulating layer so as to be in contact with the oxide semiconductor layer;

after forming the oxide insulating layer, adding oxygen into the oxide semiconductor layer through the oxide insulating layer;

after adding oxygen into the oxide semiconductor layer, performing first heat treatment on the oxide insulating layer and the oxide semiconductor layer;

after performing the first heat treatment, forming an opening in the oxide insulating layer until a source electrode layer and a drain electrode layer are exposed; and

after forming the opening in the oxide insulating layer, forming a conductive layer, wherein the conductive layer is directly connected to the source electrode layer and the drain electrode layer and is electrically connected to the oxide semiconductor layer through the opening of the oxide insulating layer.

2. The method for manufacturing a semiconductor device according to claim 1, wherein the step of adding oxygen is performed by irradiating the oxide semiconductor layer with an accelerated oxygen.

3. The method for manufacturing a semiconductor device according to claim 1, wherein the step of adding oxygen is performed by an ion implantation method or an ion doping method.

4. The method for manufacturing a semiconductor device according to claim 1, wherein the oxide insulating layer is a silicon oxide layer formed by a sputtering method.

5. The method for manufacturing a semiconductor device according to claim 1, further comprising the step of

forming the source electrode layer and the drain electrode layer between the oxide semiconductor layer and the oxide insulating layer.

6. The method for manufacturing a semiconductor device according to claim 1, wherein the oxide semiconductor layer comprises indium.

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

forming a first gate electrode layer over a substrate;

forming a gate insulating layer over the first gate electrode layer;

forming an oxide semiconductor layer over the gate insulating layer;

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

forming an oxide insulating layer over the oxide semiconductor layer, the source electrode layer, and the drain electrode layer, so as to be in contact with the oxide semiconductor layer;

after forming the oxide insulating layer, adding oxygen into the oxide semiconductor layer through the oxide insulating layer;

after adding oxygen into the oxide semiconductor layer, performing first heat treatment on the oxide insulating layer and the oxide semiconductor layer;

after performing the first heat treatment, forming an opening in the oxide insulating layer until the source electrode layer and the drain electrode layer are exposed; and

after forming the opening in the oxide insulating layer, forming a conductive layer, wherein the conductive layer is directly connected to the source electrode layer and the drain electrode layer and is electrically connected to the oxide semiconductor layer via the source electrode layer or the drain electrode layer through the opening of the oxide insulating layer.

8. The method for manufacturing a semiconductor device according to claim 7, wherein the step of adding oxygen is performed by irradiating the oxide semiconductor layer with an accelerated oxygen.

9. The method for manufacturing a semiconductor device according to claim 7, wherein the step of adding oxygen is performed by an ion implantation method or an ion doping method.

10. The method for manufacturing a semiconductor device according to claim 7, wherein the oxide insulating layer is a silicon oxide layer formed by a sputtering method.

11. The method for manufacturing a semiconductor device according to claim 7, further comprising the step of forming an insulating layer over the oxide insulating layer and the conductive layer,

wherein the insulating layer is a silicon nitride layer formed by a sputtering method.

12. The method for manufacturing a semiconductor device according to claim 7, wherein the oxide semiconductor layer comprises indium.

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

forming a gate electrode layer over a substrate;

forming a gate insulating layer over the gate electrode layer;

forming an oxide semiconductor layer over the gate insulating layer;

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

forming an oxide insulating layer over the oxide semiconductor layer, the source electrode layer, and the drain electrode layer, so as to be in contact with the oxide semiconductor layer;

after forming the oxide insulating layer, adding oxygen into the oxide semiconductor layer through the oxide insulating layer;

after adding oxygen into the oxide semiconductor layer, performing first heat treatment on the oxide insulating layer and the oxide semiconductor layer, whereby part of surfaces of the source electrode layer and the drain electrode layer is oxidized;

after performing the first heat treatment, forming an opening in the oxide insulating layer until a source electrode layer and a drain electrode layer are exposed; and

after forming the opening in the oxide insulating layer, forming a conductive layer, wherein the conductive layer is directly connected to the source electrode layer and the drain electrode layer and is electrically connected to the oxide semiconductor layer via the source electrode layer or the drain electrode layer through the opening of the oxide insulating layer.

14. The method for manufacturing a semiconductor device according to claim 13, wherein the step of adding oxygen is performed by irradiating the oxide semiconductor layer with an accelerated oxygen.

15. The method for manufacturing a semiconductor device according to claim 13, wherein the step of adding oxygen is performed by an ion implantation method or an ion doping method.

16. The method for manufacturing a semiconductor device according to claim 13, further comprising the step of forming an insulating layer over the oxide insulating layer and the conductive layer,

wherein the oxide insulating layer is a silicon oxide layer formed by a sputtering method.

17. The method for manufacturing a semiconductor device according to claim 13, wherein the oxide semiconductor layer comprises indium.