Method for manufacturing an oxide-based semiconductor thin film transistor (TFT) including out diffusing hydrogen or moisture from the oxide semiconductor layer into an adjacent insulating layer which contains a halogen element

• US 8,642,412 B2
• Filed: 10/18/2010
• Issued: 02/04/2014
• Est. Priority Date: 10/21/2009
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Yamazaki, Shunpei, Takahashi, Masahiro, Suzuki, Kunihiko
• Primary Examiner(s): MAI, ANH D
• Application Number:
  US12/906,175
• Publication Number:
  US 20110089416A1
• Time in Patent Office: 1,205 Days
• Field of Search: 438/104, 438/158, 438/164, 257/E21.466, 257/E21.468
• US Class Current: 438/158
• 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 21/02664 Aftertreatments planarisation in general H01L21/304
• CPC Class Codes: H01L 23/564 Details not otherwise provided for, e.g. protection against moisture getters H01L23/26
• CPC Class Codes: H01L 29/4908 for thin film semiconductor, e.g. gate of TFT
• 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
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Abstract

An object is to provide a semiconductor device with stable electric characteristics in which an oxide semiconductor is used. An impurity such as hydrogen or moisture (e.g., a hydrogen atom or a compound containing a hydrogen atom such as H₂O) is eliminated from an oxide semiconductor layer with use of a halogen element typified by fluorine or chlorine, so that the impurity concentration in the oxide semiconductor layer is reduced. A gate insulating layer and/or an insulating layer provided in contact with the oxide semiconductor layer can be formed to contain a halogen element. In addition, a halogen element may be attached to the oxide semiconductor layer through plasma treatment under an atmosphere of a gas containing a halogen element.

Claims

1. 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;

introducing the substrate into a first treatment chamber;

introducing a sputtering gas into the first treatment chamber;

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;

introducing the substrate into a second treatment chamber;

introducing a sputtering gas containing oxygen and a halogen element into the second treatment chamber;

forming an insulating layer over the oxide semiconductor layer, the insulating layer containing the halogen element; and

heating the substrate to diffuse hydrogen or moisture included in the oxide semiconductor layer into the insulating layer.

2. The method for manufacturing a semiconductor device according to claim 1, wherein remaining moisture is evacuated from the first treatment chamber and the second treatment chamber with use of a cryopump.

3. The method for manufacturing a semiconductor device according to claim 1, wherein fluorine or chlorine is used as the halogen element.

4. 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;

introducing the substrate into a first treatment chamber;

introducing a sputtering gas into the first treatment chamber;

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;

performing plasma treatment on the oxide semiconductor layer under an atmosphere of a gas containing a halogen element;

introducing the substrate into a second treatment chamber;

introducing a sputtering gas containing oxygen into the second treatment chamber;

forming an insulating layer over the oxide semiconductor layer; and

heating the substrate to diffuse hydrogen or moisture included in the oxide semiconductor layer into the insulating layer.

5. The method for manufacturing a semiconductor device according to claim 4, wherein remaining moisture is evacuated from the first treatment chamber and the second treatment chamber with use of a cryopump.

6. The method for manufacturing a semiconductor device according to claim 4, wherein fluorine or chlorine is used as the halogen element.

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

forming a gate electrode layer over a substrate;

introducing the substrate into a first treatment chamber, wherein a halogen element is contained in the first treatment chamber with use of a gas containing the halogen element;

forming a gate insulating layer over the gate electrode layer, the gate insulating layer containing the halogen element;

introducing the substrate into a second treatment chamber;

introducing a sputtering gas into the second treatment chamber;

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;

introducing the substrate into a third treatment chamber;

introducing a sputtering gas containing oxygen into the third treatment chamber;

forming an insulating layer over the oxide semiconductor layer; and

heating the substrate to diffuse hydrogen or moisture included in the oxide semiconductor layer into the gate insulating layer.

8. The method for manufacturing a semiconductor device according to claim 7, wherein remaining moisture is evacuated from the first treatment chamber, the second treatment chamber, and the third treatment chamber with use of a cryopump.

9. The method for manufacturing a semiconductor device according to claim 7, wherein fluorine or chlorine is used as the halogen element.