SEMICONDUCTOR DEVICE AND METHOD FOR MANUFACTURING THE SAME

• US 20100187523A1
• Filed: 01/07/2010
• Published: 07/29/2010
• Est. Priority Date: 01/23/2009
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: YAMAZAKI, Shunpei, SASAKI, Toshinari, SAKATA, Junichiro, OHARA, Hiroki, SHIMAZU, Takashi
• Granted Patent: US 8,492,756 B2
• Time in Patent Office: Days
• US Class Current: 257/43
• 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 27/1225 with semiconductor materials not belonging to the group IV of the periodic table, e.g. InGaZnO
• CPC Class Codes: H01L 29/16 including, apart from doping materials or other impurities, only elements of Group IV of the Periodic Table
• CPC Class Codes: H01L 29/78618 characterised by the drain or the source properties, e.g. the doping structure, the composition, the sectional shape or the contact structure silicide contacts, electrodes in general H01L29/458
• 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 a semiconductor device including a thin film transistor which includes an oxide semiconductor layer and has high electric characteristics. An oxide semiconductor layer including SiO_x is used in a channel formation region, and in order to reduce contact resistance with source and drain electrode layers formed using a metal material with low electric resistance, source and drain regions are provided between the source and drain electrode layers and the oxide semiconductor layer including SiO_x. The source and drain regions are formed using an oxide semiconductor layer which does not include SiO_x or an oxynitride film.

Claims

1. A semiconductor device comprising:

a gate electrode over an insulating surface;

an oxide semiconductor layer including SiO_x;

an insulating layer between the gate electrode and the oxide semiconductor layer including SiO_x; and

source and drain regions between the oxide semiconductor layer including SiO_x and source and drain electrode layers,

wherein the source and drain regions are formed using an oxynitride material.

2. The semiconductor device according to claim 1, wherein the oxide semiconductor layer including SiO_x includes tin.

3. The semiconductor device according to claim 1, wherein the oxide semiconductor layer including SiO_x includes zinc.

4. The semiconductor device according to claim 1, wherein the oxide semiconductor layer including SiO_x is formed by a sputtering method with use of an oxide semiconductor target containing SiO₂ at from 0.1 wt % to 20 wt % inclusive.

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

forming a gate electrode over an insulating surface;

forming an insulating layer over the gate electrode;

forming an oxide semiconductor layer including SiO_x over the insulating layer by a sputtering method with use of a first oxide semiconductor target containing SiO₂ at from 0.1 wt % to 20 wt % inclusive; and

forming an oxynitride layer over the oxide semiconductor layer including SiO_x by a sputtering method with use of a second oxide semiconductor target in an atmosphere containing nitrogen.

6. The method for manufacturing a semiconductor device according to claim 5, further comprising the steps of, after forming the oxynitride layer, removing a part of the oxynitride layer which overlaps with the gate electrode, so that the oxide semiconductor layer including SiO_x is partly exposed.

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

forming an oxide semiconductor layer including SiO_x over an insulating surface by a sputtering method with use of a first oxide semiconductor target containing SiO₂ at from 0.1 wt % to 20 wt % inclusive;

forming an oxynitride layer over the oxide semiconductor layer including SiO_x by a sputtering method with use of a second oxide semiconductor target in an atmosphere containing nitrogen;

forming an insulating layer covering the oxynitride layer; and

forming a gate electrode over the insulating layer.