DISPLAY DEVICE AND METHOD OF MANUFACTURING THE DISPLAY DEVICE

• US 20080029767A1
• Filed: 07/30/2007
• Published: 02/07/2008
• Est. Priority Date: 08/04/2006
• Status: Active Grant

• Current Assignee: Mitsubishi Electric Corporation
• Original Assignee: Mitsubishi Electric Corporation
• Inventors: Takeguchi, Toru, Nagata, Hitoshi
• Granted Patent: US 7,683,977 B2
• Time in Patent Office: Days
• US Class Current: 257/72
• CPC Class Codes: G02F 1/1368 in which the switching element is a three-electrode device G02F1/136277 takes precedence
• 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 29/41733 for thin film transistors with insulated gate
• CPC Class Codes: H01L 29/42384 for thin film field effect transistors, e.g. characterised by the thickness or the shape of the insulator or the dimensions, the shape or the lay-out of the conductor
• CPC Class Codes: H01L 29/458 for thin film silicon, e.g. source or drain electrode
• CPC Class Codes: H01L 29/4908 for thin film semiconductor, e.g. gate of TFT

Abstract

A display device according to an embodiment of the present invention includes: a crystalline silicon layer formed on a substrate and including a source region, a drain region, and a channel region; a wiring layer including a signal line and formed to cover at least a predetermined portion on the source region and the drain region; a gate insulating layer formed on the crystalline silicon layer and the wiring layer; a gate electrode layer formed above the gate insulating layer and including a scanning line, a gate electrode corresponding to the channel region, and a capacitor electrode corresponding to a predetermined portion of the wiring layer; an interlayer insulating film formed on the gate electrode layer; and a pixel electrode layer formed on the interlayer insulating film, and including a pixel electrode connected to the drain region or the source region through a contact hole formed in the gate insulating layer and the interlayer insulating film.

Claims

1. A display device, comprising:

a crystalline silicon layer formed on a substrate and including a source region, a drain region, and a channel region;

a wiring layer including a signal line and formed to cover at least a predetermined portion on the source region and the drain region;

a gate insulating layer formed on the crystalline silicon layer and the wiring layer;

a gate electrode layer formed above the gate insulating layer and including a scanning line, a gate electrode corresponding to the channel region, and a capacitor electrode corresponding to a predetermined portion of the wiring layer;

an interlayer insulating film formed on the gate electrode layer; and

a pixel electrode layer formed on the interlayer insulating film, and including a pixel electrode connected to the drain region or the source region through a contact hole formed in the gate insulating layer and the interlayer insulating film.

2. The display device according to claim 1, wherein the wiring layer includes at least a first layer and a second layer formed on the first layer, and

the first layer that comes into contact with the source region and the drain region is a silicon film containing a conductive impurity, and

the second layer includes a metal film.

3. The display device according to claim 1, wherein the wiring layer formed on at least one of the source region and the drain region extends up to below the gate electrode.

4. The display device according to claim 2, wherein the wiring layer formed on at least one of the source region and the drain region extends up to below the gate electrode.

7. The display device according to claim 1, wherein an interface portion between the wiring layer and the pixel electrode layer contains at least one of Ti, Cr, Zr, Ta, W, Mo, TiN, ZrN, TaN, WN, and VN.

9. The display device according to claim 1, wherein the wiring layer is made of a material having reflection characteristics.

5. A display device, comprising:

a crystalline silicon layer formed on a substrate and including a source region, a drain region, and a channel region;

a wiring layer including a signal line and formed away from the crystalline silicon layer;

a gate insulating layer formed on the crystalline silicon layer and the wiring layer;

a gate electrode layer formed above the gate insulating layer and including a scanning line, a gate electrode corresponding to the channel region, and a capacitor electrode corresponding to a predetermined portion of the wiring layer;

an interlayer insulating film formed on the gate electrode layer; and

a pixel electrode layer formed on the interlayer insulating film, and including a pixel electrode connected to the drain region or the source region through a contact hole formed in the gate insulating layer and the interlayer insulating film.

6. The display device according to claim 5, wherein the crystalline silicon layer includes a silicide layer containing at least one of Co, Ni, Mo, W, and Cr at an interface with the pixel electrode layer.

8. The display device according to claim 5, wherein an interface portion between the wiring layer and the pixel electrode layer contains at least one of Ti, Cr, Zr, Ta, W, Mo, TiN, ZrN, TaN, WN, and VN.

10. The display device according to claim 5, wherein the wiring layer is made of a material having reflection characteristics.

11. A method of manufacturing a display device, comprising:

forming a crystalline silicon layer on a substrate;

covering at least a predetermined portion on the crystalline silicon layer to form a wiring layer including a signal line;

forming a gate insulating layer on the crystalline silicon layer and the wiring layer;

forming a gate electrode layer including a scanning line, a gate electrode, and a capacitor electrode above the gate insulating layer;

forming an interlayer insulating film on the gate electrode layer and the gate insulating layer; and

forming a pixel electrode layer on the interlayer insulating film, and electrically connecting the pixel electrode layer and the wiring layer through a contact hole formed in the interlayer insulating film and the gate insulating layer.

12. A method of manufacturing a display device, comprising:

forming a crystalline silicon layer on a substrate;

forming a wiring layer including the signal lines away from the crystalline silicon layer;

forming a gate insulating layer on the crystalline silicon layer and the wiring layer;

forming a gate electrode layer including a gate electrode, the scanning lines, and a capacitor electrode on the gate insulating layer;

forming an interlayer insulating film on the gate electrode layer and the gate insulating layer; and

forming a pixel electrode layer on the interlayer insulating film and electrically connecting the pixel electrode with the wiring layer and the crystalline silicon layer through a contact hole formed in the interlayer insulating film and the gate insulating layer.

13. The method of manufacturing a display device according to claim 12, further comprising:

forming the contact hole and then depositing a metal film;

performing heat treatment on the metal film to form a metal silicide layer on a surface of the crystalline silicon layer; and

removing the metal film except the metal silicide layer; and

electrically connecting the pixel electrode with the crystalline silicon layer through the metal silicide layer.