SEMICONDUCTOR DEVICE

• US 20130280858A1
• Filed: 06/17/2013
• Published: 10/24/2013
• Est. Priority Date: 12/05/2008
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: KIMURA, Hajime
• Granted Patent: US 8,999,750 B2
• Time in Patent Office: Days
• US Class Current: 438/104
• CPC Class Codes: G02F 1/133345 Insulating layers G02F1/1335, G02F1/1337, G02F1/135, G02F1/136 take precedence
• CPC Class Codes: G02F 1/133528 Polarisers
• CPC Class Codes: G02F 1/13439 characterised by their electrical, optical, physical properties; materials therefor; method of making
• CPC Class Codes: G02F 1/136277 formed on a semiconductor substrate, e.g. of silicon
• CPC Class Codes: G02F 1/136286 Wiring, e.g. gate line, drain line
• CPC Class Codes: G02F 1/1368 in which the switching element is a three-electrode device G02F1/136277 takes precedence
• CPC Class Codes: G02F 2201/40 Arrangements for improving the aperture ratio
• 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 27/124 with a particular composition, shape or layout of the wiring layers specially adapted to the circuit arrangement, e.g. scanning lines in LCD pixel circuits wiring structures per se H01L23/52
• CPC Class Codes: H01L 27/1255 integrated with passive devices, e.g. auxiliary capacitors
• CPC Class Codes: H01L 27/1288 employing particular masking sequences or specially adapted masks, e.g. half-tone mask
• 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 29/7869 having a semiconductor body comprising an oxide semiconductor material, e.g. zinc oxide, copper aluminium oxide, cadmium stannate

Abstract

A semiconductor device includes an oxide semiconductor layer provided over a substrate having an insulating surface; a gate insulating film covering the oxide semiconductor layer; a first conductive layer and a second conductive layer laminated in this order over the gate insulating film; an insulating film covering the oxide semiconductor layer and a gate wiring including a gate electrode (the first and second conductive layers); and a third conductive layer and a fourth conductive layer laminated in this order over the insulating film and electrically connected to the oxide semiconductor layer. The gate electrode is formed using the first conductive layer. The gate wiring is formed using the first conductive layer and the second conductive layer. A source electrode is formed using the third conductive layer. A source wiring is formed using the third conductive layer and the fourth conductive layer.

Claims

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

forming an oxide semiconductor film over a substrate;

forming a silicon nitride film over the oxide semiconductor film;

forming a silicon oxide film over the silicon nitride film;

removing part of the silicon oxide film;

forming a conductive film having a light-transmitting property over the silicon oxide film;

forming a resist mask using a multi-tone mask over the oxide semiconductor film, and

ashing the resist mask to reduce the resist mask in size.

2. The method for manufacturing the semiconductor device according to claim 1,

wherein the conductive film having a light-transmitting property is an indium tin oxide (ITO) film.

3. The method for manufacturing the semiconductor device according to claim 1,

wherein the multi-tone mask is a half-tone mask.

4. The method for manufacturing the semiconductor device according to claim 1,

wherein the ashing step is performed by using oxygen plasma.

5. The method for manufacturing the semiconductor device according to claim 1,

wherein the oxide semiconductor film includes indium, gallium, and zinc.

6. The method for manufacturing the semiconductor device according to claim 1,

wherein the semiconductor device comprises a capacitor portion including a second oxide semiconductor film formed by the same process as the oxide semiconductor film and a second conductive film having a light-transmitting property formed by the same process as the conductive film having a light-transmitting property.

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

forming an oxide semiconductor film over a substrate;

forming a copper film over the oxide semiconductor film;

forming a resist mask using a multi-tone mask over the copper film;

etching the copper film using the resist mask to form a copper electrode;

ashing the resist mask to reduce the resist mask in size;

forming a first insulating film over the copper electrode;

forming a second insulating film over the first insulating film;

removing part of the second insulating film; and

forming a conductive film having a light-transmitting property over the second insulating film.

8. The method for manufacturing the semiconductor device according to claim 7,

wherein the conductive film having a light-transmitting property is an indium tin oxide (ITO) film.

9. The method for manufacturing the semiconductor device according to claim 7,

wherein the multi-tone mask is a half-tone mask.

10. The method for manufacturing the semiconductor device according to claim 7,

wherein the ashing step is performed by using oxygen plasma.

11. The method for manufacturing the semiconductor device according to claim 7,

wherein the oxide semiconductor film includes indium, gallium, and zinc.

12. The method for manufacturing the semiconductor device according to claim 7,

wherein the semiconductor device comprises a capacitor portion including a second oxide semiconductor film formed by the same process as the oxide semiconductor film and a second conductive film having a light-transmitting property formed by the same process as the conductive film having a light-transmitting property.

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

forming an oxide semiconductor film over a substrate;

forming a copper film over the oxide semiconductor film;

forming a resist mask using a multi-tone mask over the copper film;

etching the copper film using the resist mask to form a copper electrode;

ashing the resist mask to reduce the resist mask in size;

forming a silicon nitride film over the copper electrode;

forming an insulating film over the silicon nitride film;

removing part of the insulating film; and

forming a conductive film having a light-transmitting property over the insulating film.

14. The method for manufacturing the semiconductor device according to claim 13,

wherein the conductive film having a light-transmitting property is an indium tin oxide (ITO) film.

15. The method for manufacturing the semiconductor device according to claim 13,

wherein the multi-tone mask is a half-tone mask.

16. The method for manufacturing the semiconductor device according to claim 13,

wherein the ashing step is performed by using oxygen plasma.

17. The method for manufacturing the semiconductor device according to claim 13,

wherein the oxide semiconductor film includes indium, gallium, and zinc.

18. The method for manufacturing the semiconductor device according to claim 13,

wherein the semiconductor device comprises a capacitor portion including a second oxide semiconductor film formed by the same process as the oxide semiconductor film and a second conductive film having a light-transmitting property formed by the same process as the conductive film having a light-transmitting property.