Semiconductor device and manufacturing method thereof

• US 6,825,488 B2
• Filed: 01/26/2001
• Issued: 11/30/2004
• Est. Priority Date: 01/26/2000
• Status: Expired due to Term

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Koyama, Jun, Yamazaki, Shunpei
• Primary Examiner(s): Whitehead, Jr., Carl
• Assistant Examiner(s): MENZ, LAURA MARY
• Application Number:
  US09/769,765
• Publication Number:
  US 20020110941A1
• Time in Patent Office: 1,404 Days
• Field of Search: 257/40, 257/66, 257/72, 257/350, 257/59, 257/344, 257/392, 257/408, 257/79, 349/113, 349/41, 359/59, 359/87, 438/486, 438/487, 438/148, 438/149, 438/479
• US Class Current: 257/40
• CPC Class Codes: G02F 1/133512 Light shielding layers, e.g. black matrix G02F1/136209 takes 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 2203/02 reflective
• CPC Class Codes: H01L 21/32136 using plasmas
• 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 29/66757 Lateral single gate single channel transistors with non-inverted structure, i.e. the channel layer is formed before the gate
• 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

Abstract

The aperture ratio of a pixel of a reflecting type display device is improved without increasing the number of masks and without using a black mask. Locations for light shielding between pixels are arranged such that a pixel electrode overlaps with a portion of a gate wiring and a source wiring. In locations for shielding TFTs, a high pixel aperture ratio is realized by forming a color filter (red, or lamination of red and blue), formed on an opposing substrate.

Claims

1. A semiconductor device comprising:

a first semiconductor layer and a second semiconductor layer over an insulating surface;

a first insulating film over the first semiconductor layer and over the second semiconductor layer;

a first electrode over the first insulating film, said first electrode overlapping the first semiconductor layer;

a second electrode over the first insulating film, said second electrode overlapping the second semiconductor layer;

a source wiring over the first insulating film;

a second insulating film covering the first electrode and the source wiring;

a gate wiring over the second insulating film, said gate wiring connected to the first electrode;

a connection electrode over the second insulating film, said connection electrode connected to the source wiring and the first semiconductor layer; and

a pixel electrode over the second insulating film, said pixel electrode connected to the first semiconductor layer;

wherein the pixel electrode overlays the source wiring with the second insulating film interposed therebetween.

2. A device according to claim 1, wherein the first electrode is a gate electrode.

3. A device according to claim 1, wherein a storage capacitor is formed by the second semiconductor layer, the second electrode, and the first insulating film.

4. A device according to claim 1, wherein:

the first semiconductor layer contains an impurity element which imparts one conductivity into the semiconductor; and

the second semiconductor layer contains an impurity element which imparts one conductivity, opposite to that contained in the first semiconductor layer, into the semiconductor.

5. A device according to claim 1, wherein the gate wiring comprising an element selected from the group consisting of polysilicon doped with an impurity element which imparts one conductivity;

W;

WSix;

Al;

Cu;

Ta;

Cr; and

Mo as its main constituent, and a lamination film of the elements.

6. A device according to claim 1, wherein the second insulating film is composed of a first insulating layer having silicon as its main constituent, and a second insulating layer comprising an organic resin material.

7. A device according to claim 1, wherein the semiconductor device is a reflecting type liquid crystal display device.

8. A device according to claim 1, wherein the semiconductor device is a device selected from the group consisting of a personal computer, a video camera, a portable information terminal, a digital camera, a digital video disk player, and an electronic amusement device.

9. A device according to claim 1, wherein said first insulating film is a gate insulating film.

10. A device according to claim 1, wherein the first electrode and the source wiring comprise the same material and are formed by the same process.

11. A device according to claim 1, wherein the second electrode is a capacitor electrode.