SEMICONDUCTOR DEVICE AND METHOD FOR MANUFACTURING THE SAME

• US 20130069059A1
• Filed: 11/08/2012
• Published: 03/21/2013
• Est. Priority Date: 02/05/2010
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: YAMAZAKI, Shunpei
• Granted Patent: US 9,202,923 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 21/02631 Physical deposition at reduced pressure, e.g. MBE, sputtering, evaporation
• 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 27/1266 the substrate on which the devices are formed not being the final device substrate, e.g. using a temporary substrate
• CPC Class Codes: H01L 29/1033 with insulated gate, e.g. characterised by the length, the width, the geometric contour or the doping structure with channel and gate aligned in the lengthwise direction H01L29/42376; with buried channel H01L29/7838
• CPC Class Codes: H01L 29/24 including, apart from doping materials or other impurities, only semiconductor materials not provided for in groups H01L29/16, H01L29/18, H01L29/20, H01L29/22 including organic materials H10K99/00
• CPC Class Codes: H01L 29/66742 Thin film unipolar transistors
• 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

Abstract

A more convenient and highly reliable semiconductor device which has a transistor including an oxide semiconductor with higher impact resistance used for a variety of applications is provided. A semiconductor device has a bottom-gate transistor including a gate electrode layer, a gate insulating layer, and an oxide semiconductor layer over a substrate, an insulating layer over the transistor, and a conductive layer over the insulating layer. The insulating layer covers the oxide semiconductor layer and is in contact with the gate insulating layer. In a channel width direction of the oxide semiconductor layer, end portions of the gate insulating layer and the insulating layer are aligned with each other over the gate electrode layer, and the conductive layer covers a channel formation region of the oxide semiconductor layer and the end portions of the gate insulating layer and the insulating layer and is in contact with the gate electrode layer.

Claims

1. A semiconductor device comprising:

an oxide layer comprising an oxide semiconductor;

an insulating layer over the oxide layer; and

a gate electrode over the insulating layer, the gate electrode overlapping with the oxide layer,

wherein the gate electrode faces to a side surface of the oxide layer with the insulating layer interposed therebetween.

2. The semiconductor device according to claim 1, further comprising:

a second insulating layer under the oxide layer, the second insulating layer being in contact with the insulating layer.

3. The semiconductor device according to claim 1, further comprising:

a source electrode over and electrically connected to the oxide layer; and

a drain electrode over and electrically connected to the oxide layer.

4. The semiconductor device according to claim 3, wherein the gate electrode overlaps with a part of the source electrode and a part of the drain electrode.

5. The semiconductor device according to claim 1, further comprising:

a source electrode under and electrically connected to the oxide layer; and

a drain electrode under and electrically connected to the oxide layer.

6. The semiconductor device according to claim 5, wherein the gate electrode overlaps with a part of the source electrode and a part of the drain electrode.

7. The semiconductor device according to claim 2, wherein the gate electrode faces to a side surface of the second insulating layer.

8. The semiconductor device according to claim 1, further comprising:

a conductive layer under the oxide layer, the conductive layer being in contact with the gate electrode.

9. A semiconductor device comprising:

an oxide layer comprising an oxide semiconductor;

a source electrode over and electrically connected to the oxide layer;

a drain electrode over and electrically connected to the oxide layer;

an insulating layer over the oxide layer, the source electrode, and the drain electrode; and

a gate electrode over the insulating layer, the gate electrode overlapping with the oxide layer,

wherein the gate electrode faces to a side surface of the oxide layer with the insulating layer interposed therebetween,

wherein the oxide layer comprises a crystal region, and

wherein the oxide layer has a recessed portion between the source electrode and the drain electrode.

10. The semiconductor device according to claim 9, further comprising:

a second insulating layer under the oxide layer, the second insulating layer being in contact with the insulating layer.

11. The semiconductor device according to claim 9, wherein the gate electrode overlaps with a part of the source electrode and a part of the drain electrode.

12. The semiconductor device according to claim 10, wherein the gate electrode faces to a side surface of the second insulating layer.

13. The semiconductor device according to claim 9, further comprising:

a conductive layer under the oxide layer, the conductive layer being in contact with the gate electrode.

14. The semiconductor device according to claim 9, wherein the crystal region is c-axis-aligned perpendicularly to a surface of the oxide layer.

15. A semiconductor device comprising:

an oxide layer that comprises an oxide comprising indium;

an insulating layer over the oxide layer; and

a gate electrode over the insulating layer, the gate electrode overlapping with the oxide layer,

wherein the oxide layer comprises a first oxide layer and a second oxide layer on the first oxide layer, and

wherein the gate electrode faces to a side surface of the second oxide layer with the insulating layer interposed therebetween.

16. The semiconductor device according to claim 15, further comprising:

a second insulating layer under the oxide layer, the second insulating layer being in contact with the insulating layer.

17. The semiconductor device according to claim 15, further comprising:

a source electrode over and electrically connected to the oxide layer; and

a drain electrode over and electrically connected to the oxide layer.

18. The semiconductor device according to claim 17, wherein the gate electrode overlaps with a part of the source electrode and a part of the drain electrode.

19. The semiconductor device according to claim 15, further comprising:

a source electrode under and electrically connected to the oxide layer; and

a drain electrode under and electrically connected to the oxide layer.

20. The semiconductor device according to claim 19, wherein the gate electrode overlaps with a part of the source electrode and a part of the drain electrode.

21. The semiconductor device according to claim 16, wherein the gate electrode faces to a side surface of the second insulating layer.

22. The semiconductor device according to claim 15, further comprising:

a conductive layer under the oxide layer, the conductive layer being in contact with the gate electrode.

23. The semiconductor device according to claim 15, wherein the first oxide layer is an oxide semiconductor layer.

24. The semiconductor device according to claim 15, wherein the first oxide layer comprises a crystal region.

25. The semiconductor device according to claim 15, wherein the second oxide layer is an oxide semiconductor layer.

26. The semiconductor device according to claim 15, wherein the second oxide layer comprises a crystal region.

27. The semiconductor device according to claim 15, wherein the second oxide layer comprises a single crystal region.

28. The semiconductor device according to claim 15, wherein the second oxide layer comprises a crystal region which is c-axis-aligned perpendicularly to a surface of the second oxide layer.

29. The semiconductor device according to claim 15, wherein the oxide further comprises gallium and zinc.

30. The semiconductor device according to claim 15, wherein the second oxide layer is thicker than the first oxide layer.