Semiconductor device

• US 8,785,926 B2
• Filed: 04/11/2013
• Issued: 07/22/2014
• Est. Priority Date: 04/17/2012
• Status: Active Grant

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.), Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.), Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Yokoyama, Masatoshi, Murakawa, Tsutomu, Okazaki, Kenichi, Sakakura, Masayuki, Matsuo, Takuya, Kanzaki, Yosuke, Matsukizono, Hiroshi, Yamamoto, Yoshitaka
• Primary Examiner(s): Dang, Trung Q
• Application Number:
  US13/860,879
• Publication Number:
  US 20130270554A1
• Time in Patent Office: 467 Days
• Field of Search: 257/43, 257/E31.032
• US Class Current: 257/43
• 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

The semiconductor conductor device includes a gate electrode 106, an oxide semiconductor film 110, a source electrode 114a and a drain electrode 114b, and a channel region formed in the oxide semiconductor film. The channel region is formed between a first side surface 214a of the source electrode and a second side surface 214b of the drain electrode opposite to the first side surface 214a. The oxide semiconductor film has a side surface which overlaps with the gate electrode, which has a first high resistance region positioned between a first region 206a that is the nearest to one end 314a of the first side surface 214a and a second region 206b that is the nearest to one end 314b of the second side surface 214b. The first high resistance region has a corrugated side surface or the like.

Claims

1. A semiconductor device comprising:

a gate electrode;

a gate insulating film over the gate electrode; and

an oxide semiconductor film over the gate insulating film, wherein the oxide semiconductor film overlaps with the gate electrode,

wherein the oxide semiconductor film comprises a side surface which overlaps with the gate electrode, and

wherein at least part of the side surface comprises an uneven shape.

2. The semiconductor device according to claim 1,

wherein the whole of the side surface of the oxide semiconductor film is a high resistance region, and

wherein the high resistance region comprises at least one of a corrugated side surface, a waved side surface, a jagged side surface, and a side surface where a projected portion and a depressed portion are alternately arranged.

3. The semiconductor device according to claim 1,

wherein the oxide semiconductor film is a film comprising an oxide of one or more elements selected from indium, zinc, gallium, and tin.

4. The semiconductor device according to claim 1,

wherein the oxide semiconductor film comprises a crystal portion where a c-axis is aligned in a direction parallel to a normal vector of a surface where the oxide semiconductor film is formed.

5. A semiconductor device comprising:

a gate electrode;

an oxide semiconductor film comprising a channel region; and

a source electrode and a drain electrode,

wherein the channel region is positioned between a first side surface of the source electrode and a second side surface of the drain electrode opposite to the first side surface,

wherein the oxide semiconductor film comprises a side surface which overlaps with the gate electrode,

wherein the side surface of the oxide semiconductor film comprises a first high resistance region positioned between a first region nearest to one end of the first side surface and a second region nearest to one end of the second side surface, and

wherein the first high resistance region comprises at least one of a corrugated side surface, a waved side surface, a jagged side surface, and a side surface where a projected portion and a depressed portion are alternately arranged.

6. The semiconductor device according to claim 5,

wherein the side surface of the oxide semiconductor film comprises a second high resistance region positioned between a third region nearest to the other end of the first side surface and a fourth region nearest to the other end of the second side surface, and

wherein the second high resistance region comprises at least one of a corrugated side surface, a waved side surface, a jagged side surface, and a side surface where a projected portion and a depressed portion are alternately arranged.

7. The semiconductor device according to claim 5,

wherein the first high resistance region is continuous from the first region to the second region.

8. The semiconductor device according to claim 6,

wherein the second high resistance region is continuous from the third region to the fourth region.

9. The semiconductor device according to claim 5,

wherein the whole of the side surface of the oxide semiconductor film is a high resistance region, and

wherein the high resistance region comprises at least one of a corrugated side surface, a waved side surface, a jagged side surface, and a side surface where a projected portion and a depressed portion are alternately arranged.

10. The semiconductor device according to claim 5,

wherein the oxide semiconductor film is a film comprising an oxide of one or more elements selected from indium, zinc, gallium, and tin.

11. The semiconductor device according to claim 5,

wherein the oxide semiconductor film comprises a crystal portion where a c-axis is aligned in a direction parallel to a normal vector of a surface where the oxide semiconductor film is formed.

12. A semiconductor device comprising:

a gate electrode;

a gate insulating film over the gate electrode;

an oxide semiconductor film over the gate insulating film, the oxide semiconductor film comprising a channel region; and

a source electrode and a drain electrode each electrically connected to the oxide semiconductor film,

wherein the channel region is positioned between a first side surface of the source electrode and a second side surface of the drain electrode opposite to the first side surface,

wherein the oxide semiconductor film comprises a side surface which overlaps with the gate electrode,

wherein the side surface of the oxide semiconductor film comprises a first high resistance region positioned between a first region nearest to one end of the first side surface and a second region nearest to one end of the second side surface, and

wherein the first high resistance region comprises at least one of a corrugated side surface, a waved side surface, a jagged side surface, and a side surface where a projected portion and a depressed portion are alternately arranged.

13. The semiconductor device according to claim 12,

wherein the side surface of the oxide semiconductor film comprises a second high resistance region positioned between a third region nearest to the other end of the first side surface and a fourth region nearest to the other end of the second side surface, and

wherein the second high resistance region comprises at least one of a corrugated side surface, a waved side surface, a jagged side surface, and a side surface where a projected portion and a depressed portion are alternately arranged.

14. The semiconductor device according to claim 12,

wherein the first high resistance region is continuous from the first region to the second region.

15. The semiconductor device according to claim 13,

wherein the second high resistance region is continuous from the third region to the fourth region.

16. The semiconductor device according to claim 12,

wherein the whole of the side surface of the oxide semiconductor film is a high resistance region, and

wherein the high resistance region comprises at least one of a corrugated side surface, a waved side surface, a jagged side surface, and a side surface where a projected portion and a depressed portion are alternately arranged.

17. The semiconductor device according to claim 12,

wherein the oxide semiconductor film is a film comprising an oxide of one or more elements selected from indium, zinc, gallium, and tin.

18. The semiconductor device according to claim 12,

wherein the oxide semiconductor film comprises a crystal portion where a c-axis is aligned in a direction parallel to a normal vector of a surface where the oxide semiconductor film is formed.