SEMICONDUCTOR DEVICE

• US 20130270616A1
• Filed: 04/09/2013
• Published: 10/17/2013
• Est. Priority Date: 04/13/2012
• Status: Abandoned Application

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Yamazaki, Shunpei
• Application Number:
  US13/859,086
• Publication Number:
  US 20130270616A1
• Time in Patent Office: Days
• US Class Current: 257/288
• 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 29/78 with field effect produced by an insulated gate H01L29/7725, H01L29/775, H01L29/778 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: H10B 41/70 the floating gate being an electrode shared by two or more components

Abstract

A semiconductor device preventing a defect in manufacturing process, such as disconnection of a film to be formed. Further, a semiconductor device with favorable electric characteristics and high performance can be provided. In a top-gate semiconductor device in which a source electrode and a drain electrode are provided in contact with an oxide semiconductor film, a sidewall insulating film is provided to fill a recessed portion between the source electrode and a gate electrode and a recessed portion between the drain electrode and the gate electrode, which cause disconnection of a film to be formed on and in contact with the gate electrode. Further, the sidewall insulating film is provided so that a recessed portion is not formed between the sidewall insulating film and another film included in the semiconductor device.

Claims

1. A semiconductor device comprising:

a substrate;

a semiconductor film over the substrate;

a source electrode and a drain electrode in contact with the semiconductor film;

a gate electrode over the semiconductor film;

a sidewall insulating film in contact with a side surface of the gate electrode; and

a gate insulating film interposed between the semiconductor film and the gate electrode,

wherein the sidewall insulating film fills a recessed portion between the source electrode and the gate electrode.

3. The semiconductor device according to claim 1,

further comprising an insulating film over the source electrode and the drain electrode, and on and in contact with the sidewall insulating film and a top surface of the gate electrode.

5. The semiconductor device according to claim 1,

wherein the sidewall insulating film overlaps a corner portion formed by a surface of the source electrode facing the gate electrode and a top surface of the source electrode.

7. The semiconductor device according to claim 1,

wherein a side edge of the sidewall insulating film is positioned at a corner portion formed by a surface of the source electrode facing the gate electrode and a top surface of the source electrode.

9. The semiconductor device according to claim 1,

wherein the semiconductor film includes a first region that overlaps with the gate electrode, a pair of second regions between which the first region is provided, and a pair of third regions between which the first region and the pair of second regions are provided, and

wherein the second regions contain a dopant.

11. The semiconductor device according to claim 1,

wherein the semiconductor film includes a first region that overlaps with the gate electrode, a pair of second regions between which the first region is provided, and a pair of third regions between which the first region and the pair of second regions are provided, and

wherein the third regions contain a dopant.

13. The semiconductor device according to claim 1,

wherein the semiconductor film includes a first region that overlaps with the gate electrode, a pair of second regions between which the first region is provided, and a pair of third regions between which the first region and the pair of second regions are provided,

wherein the second regions contain a first dopant and the third regions contain a second dopant, and

wherein a second dopant concentration of the third regions is higher than a first dopant concentration of the second regions.

15. The semiconductor device according to claim 13,

wherein the first dopant and the second dopant are a same impurity element.

17. The semiconductor device according to claim 1,

wherein the semiconductor film comprises an oxide semiconductor.

19. An electronic appliance including the semiconductor device according to claim 1.

2. A semiconductor device comprising:

a substrate;

a semiconductor film over the substrate;

a source electrode and a drain electrode in contact with the semiconductor film;

a gate electrode over the semiconductor film;

a sidewall insulating film in contact with a side surface of the gate electrode; and

a gate insulating film interposed between the semiconductor film and the gate electrode and between the source electrode and the sidewall insulating film;

wherein the sidewall insulating film fills a recessed portion between the source electrode and the gate electrode.

4. The semiconductor device according to claim 2,

further comprising an insulating film over the source electrode and the drain electrode, and on and in contact with the sidewall insulating film and a top surface of the gate electrode.

6. The semiconductor device according to claim 2,

wherein the sidewall insulating film overlaps a corner portion formed by a surface of the gate insulating film overlapping the source electrode and facing the gate electrode and a top surface of the gate insulating film.

8. The semiconductor device according to claim 2,

wherein a side edge of the sidewall insulating film is positioned at a corner portion formed by a surface of the gate insulating film overlapping the source electrode and facing the gate electrode and a top surface of the gate insulating film.

10. The semiconductor device according to claim 2,

wherein the semiconductor film includes a first region that overlaps with the gate electrode, a pair of second regions between which the first region is provided, and a pair of third regions between which the first region and the pair of second regions are provided, and

wherein the second regions contain a dopant.

12. The semiconductor device according to claim 2,

wherein the semiconductor film includes a first region that overlaps with the gate electrode, a pair of second regions between which the first region is provided, and a pair of third regions between which the first region and the pair of second regions are provided, and

wherein the third regions contain a dopant.

14. The semiconductor device according to claim 2,

wherein the semiconductor film includes a first region that overlaps with the gate electrode, a pair of second regions between which the first region is provided, and a pair of third regions between which the first region and the pair of second regions are provided,

wherein the second regions contain a first dopant and the third regions contain a second dopant, and

wherein a second dopant concentration of the third regions is higher than a first dopant concentration of the second regions.

16. The semiconductor device according to claim 14,

wherein the first dopant and the second dopant are a same impurity element.

18. The semiconductor device according to claim 2,

wherein the semiconductor film comprises an oxide semiconductor.

20. An electronic appliance including the semiconductor device according to claim 2.