Semiconductor device and method of manufacturing the same

• US 7,915,615 B2
• Filed: 07/07/2009
• Issued: 03/29/2011
• Est. Priority Date: 02/22/2000
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Koyama, Jun, Yamazaki, Shunpei
• Primary Examiner(s): Mandala; Victor A
• Application Number:
  US12/498,696
• Publication Number:
  US 20090267073A1
• Time in Patent Office: 630 Days
• Field of Search: 257/59, 257/72, 257/88, 257/89, 257/E33.062, 257/E33.064
• US Class Current: 257/59
• CPC Class Codes: G02F 1/133345 Insulating layers G02F1/1335, G02F1/1337, G02F1/135, G02F1/136 take precedence
• CPC Class Codes: G02F 1/133512 Light shielding layers, e.g. black matrix G02F1/136209 takes precedence
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G02F 1/133784 by rubbing
• CPC Class Codes: G02F 1/13394 spacers regularly patterned on the cell subtrate, e.g. walls, pillars G02F1/133377 takes precedence
• CPC Class Codes: G02F 1/134336 Matrix
• CPC Class Codes: G02F 1/134363 for applying an electric field parallel to the substrate, i.e. in-plane switching [IPS]
• CPC Class Codes: G02F 1/13439 characterised by their electrical, optical, physical properties; materials therefor; method of making
• CPC Class Codes: G02F 1/13454 Drivers integrated on the active matrix substrate G02F1/136277 takes precedence
• CPC Class Codes: G02F 1/1362 Active matrix addressed cells G02F1/134336, G02F1/134363 take precedence
• CPC Class Codes: G02F 1/136213 Storage capacitors associated with the pixel electrode
• CPC Class Codes: G02F 1/136227 Through-hole connection of the pixel electrode to the active element through an insulation layer
• 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 2201/123 pixel
• CPC Class Codes: H01L 2029/7863 with an LDD consisting of more than one lightly doped zone or having a non-homogeneous dopant distribution, e.g. graded LDD
• CPC Class Codes: H01L 21/02675 using laser beams
• CPC Class Codes: H01L 27/1214 comprising a plurality of TFTs formed on a non-semiconducting substrate, e.g. driving circuits for AMLCDs
• CPC Class Codes: H01L 27/1222 with a particular composition, shape or crystalline structure of the active layer
• 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 27/1248 : with a particular composition or shape of the interlayer dielectric specially adapted to the circuit arrangement
• CPC Class Codes: H01L 27/1255 : integrated with passive devices, e.g. auxiliary capacitors
• CPC Class Codes: H01L 27/1274 : using crystallisation of amorphous semiconductor or recrystallisation of crystalline semiconductor
• CPC Class Codes: H01L 27/1288 : employing particular masking sequences or specially adapted masks, e.g. half-tone mask
• 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
• CPC Class Codes: H01L 29/786 : Thin film transistors, i.e. transistors with a channel being at least partly a thin film transistors having only the source or the drain region on an insulator layer H01L29/0653; thin film FinFETs H01L29/785
• CPC Class Codes: H01L 29/78621 : with LDD structure or an extension or an offset region or characterised by the doping profile
• CPC Class Codes: H01L 29/78627 : with a significant overlap between the lightly doped drain and the gate electrode, e.g. GOLDD
• CPC Class Codes: H01L 29/78633 : with a light shield
• CPC Class Codes: H01L 29/78645 : with multiple gate
• CPC Class Codes: H01L 29/78675 : with normal-type structure, e.g. with top gate

Abstract

The present invention improves the aperture ratio of a pixel of a reflection-type display device or a reflection type display device without increasing the number of masks and without using a blackmask. A pixel electrode (167) is arranged so as to partially overlap a source wiring (137) for shielding the gap between pixels from light, and a thin film transistor is arranged so as to partially overlap a gate wiring (166) for shielding a channel region of the thin film transistor from light, thereby realizing a high pixel aperture ratio.

Claims

1. A display device comprising:

a pixel portion comprising;

a transistor including a gate electrode and a semiconductor layer;

a first wiring on a same surface as the gate electrode;

a first electrode over the first wiring, and electrically connected to the first wiring and the semiconductor layer, the first electrode comprising a first titanium film, a first aluminum film over the first titanium film and a second titanium film over the first aluminum film;

a second electrode on a same surface as the first electrode, and electrically connected to the semiconductor layer; and

a pixel electrode over the second electrode, and electrically connected to the second electrode; and

an external input terminal portion comprising;

a second wiring on the same surface as the gate electrode; and

a third wiring over the second wiring, and electrically connected to the second wiring, the third wiring comprising a third titanium film, a second aluminum film over the third titanium film and a fourth titanium film over the second aluminum film.

2. A display device according to claim 1, wherein the semiconductor layer is a crystalline semiconductor film.

3. A display device according to claim 1, wherein the display device is incorporated in at least one selected from the group consisting of a personal computer, a video camera, a portable information terminal, a digital camera, a digital video disk player, a portable telephone, an electronic book, a projector, a head mounted type display, and an electric game appliance.

4. A display device comprising:

a pixel portion comprising;

a transistor;

a first wiring on a same surface as a gate electrode of the transistor;

a first electrode over the first wiring, and electrically connected to the first wiring and one of a source and a drain of the transistor, the first electrode comprising a first titanium film, a first aluminum film over the first titanium film and a second titanium film over the first aluminum film;

a second electrode on a same surface as the first electrode, and electrically connected to the other of the source and the drain of the transistor; and

a pixel electrode over the second electrode, and electrically connected to the second electrode; and

an external input terminal portion comprising;

a second wiring on the same surface as the gate electrode; and

a third wiring over the second wiring, and electrically connected to the second wiring, the third wiring comprising a third titanium film, a second aluminum film over the third titanium film and a fourth titanium film over the second aluminum film.

5. A display device according to claim 4, wherein the display device is incorporated in at least one selected from the group consisting of a personal computer, a video camera, a portable information terminal, a digital camera, a digital video disk player, a portable telephone, an electronic book, a projector, a head mounted type display, and an electric game appliance.

6. A display device comprising:

a pixel portion comprising;

a transistor including a gate electrode and a semiconductor layer;

a first wiring on a same surface as the gate electrode;

a first electrode over the first wiring, and electrically connected to the first wiring and the semiconductor layer;

a second electrode on a same surface as the first electrode, and electrically connected to the semiconductor layer; and

a pixel electrode over the second electrode, and electrically connected to the second electrode; and

an external input terminal portion comprising;

a second wiring on the same surface as the gate electrode;

a third wiring on the same surface as the first electrode, and electrically connected to the second wiring; and

a transparent conductive film on the same surface as the pixel electrode, and electrically connected to the third wiring.

7. A display device according to claim 6, wherein the semiconductor layer is a crystalline semiconductor film.

8. A display device according to claim 6, further comprising a flexible printed circuit provided over the transparent conductive film, and electrically connected to the transparent conductive film.

9. A display device according to claim 6, wherein the transparent conductive film contains at least one selected from the group consisting of indium oxide, an alloy of indium oxide and tin oxide, and an alloy of indium oxide and zinc oxide.

10. A display device according to claim 6, wherein the display device is incorporated in at least one selected from the group consisting of a personal computer, a video camera, a portable information terminal, a digital camera, a digital video disk player, a portable telephone, an electronic book, a projector, a head mounted type display, and an electric game appliance.

11. A display device comprising:

a pixel portion comprising;

a transistor;

a first wiring on a same surface as a gate electrode of the transistor;

a first electrode over the first wiring, and electrically connected to the first wiring and one of a source and a drain of the transistor;

a second electrode on a same surface as the first electrode, and electrically connected to the other of the source and the drain of the transistor; and

a pixel electrode over the second electrode, and electrically connected to the second electrode; and

an external input terminal portion comprising;

a second wiring on the same surface as the gate electrode;

a third wiring on the same surface as the first electrode, and electrically connected to the second wiring; and

a transparent conductive film on the same surface as the pixel electrode, and electrically connected to the third wiring.

12. A display device according to claim 11, further comprising a flexible printed circuit provided over the transparent conductive film, and electrically connected to the transparent conductive film.

13. A display device according to claim 11, wherein the transparent conductive film contains at least one selected from the group consisting of indium oxide, an alloy of indium oxide and tin oxide, and an alloy of indium oxide and zinc oxide.

14. A display device according to claim 11, wherein the display device is incorporated in at least one selected from the group consisting of a personal computer, a video camera, a portable information terminal, a digital camera, a digital video disk player, a portable telephone, an electronic book, a projector, a head mounted type display, and an electric game appliance.