Semiconductor device and a method of manufacturing the same

• US 8,300,201 B2
• Filed: 08/08/2011
• Issued: 10/30/2012
• Est. Priority Date: 03/13/2000
• Status: Expired due to Fees

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Yamazaki, Shunpei, Koyama, Jun, Arai, Yasuyuki, Kuwabara, Hideaki
• Primary Examiner(s): KIM, RICHARD H
• Application Number:
  US13/205,029
• Publication Number:
  US 20120012851A1
• Time in Patent Office: 449 Days
• Field of Search: None
• US Class Current: 349/152
• CPC Class Codes: G02F 1/13452 Conductors connecting driver circuitry and terminals of panels
• 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 27/1237 with a different composition, shape, layout or thickness of the gate insulator in different devices
• 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 29/66765 Lateral single gate single channel transistors with inverted structure, i.e. the channel layer is formed after the gate
• 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 29/78675 with normal-type structure, e.g. with top gate
• CPC Class Codes: H01L 29/78678 with inverted-type structure, e.g. with bottom gate

Abstract

A pixel TFT formed in a pixel region is formed on a first substrate by a channel etch type reverse stagger type TFT, and patterning of a source region and a drain region, and patterning of a pixel electrode are performed by the same photomask. A driver circuit formed by using TFTs having a crystalline semiconductor layer, and an input-output terminal dependent on the driver circuit, are taken as one unit. A plurality of units are formed on a third substrate, and afterward the third substrate is partitioned into individual units, and the obtained stick drivers are mounted on the first substrate.

Claims

1. A semiconductor device comprising:

a first substrate;

reverse stagger type thin film transistors, comprising an amorphous semiconductor layer and arranged in a matrix shape in a pixel region over the first substrate;

a second substrate on which an opposing electrode corresponding to said pixel region is formed;

a plurality of third substrates made from glass or quartz;

a first driver circuit over one of the plurality of third substrates;

a second driver circuit over another one of the plurality of third substrates, each of the first driver circuit and the second driver circuit comprising a plurality of thin film transistors comprising a crystalline semiconductor; and

a liquid crystal layer sandwiched between said first substrate and said second substrate,

wherein at least one end surface of said amorphous semiconductor layer of at least one of said reverse stagger type thin film transistors, and at least one end surface of a first conductive layer formed on said amorphous semiconductor layer, are substantially coextensive with each other;

wherein the plurality of said third substrates are disposed over said first substrate; and

wherein the plurality of thin film transistors of the first driver circuit comprises a first gate insulating film and the plurality of thin film transistors of the second driver circuit comprises a second gate insulating film having a different thickness from the first gate insulating film.

2. A display device comprising:

a first thin film transistor comprising a gate electrode over a substrate, an insulating film formed over the gate electrode, a first semiconductor film formed over the insulating film, a pair of second semiconductor films formed over the first semiconductor film, and a pair of electrodes over the pair of second semiconductor films;

a pixel electrode in electrical contact with one of the pair of electrodes;

a gate wiring between the substrate and the insulating film, wherein the gate wiring is continuous to the gate electrode;

a source wiring being continuous to the other of the pair of electrodes, the source wiring comprising a conductive layer and extending across the gate wiring;

a third semiconductor film extending along and below the source wiring, the third semiconductor film being continuous to the first semiconductor film;

a fourth semiconductor film between the third semiconductor film and the source wiring, the fourth semiconductor film extending along the source wiring and being continuous to one of the pair of second semiconductor films; and

a driver circuit electrically connected to the source wiring, the driver circuit comprising a second transistor provided over the substrate.

3. The display device according to claim 2, wherein a channel forming region of the first thin film transistor comprises amorphous silicon.

4. The display device according to claim 2, wherein the second transistor is a thin film transistor formed on a second substrate.

5. The display device according to claim 2, wherein a channel forming region of the second transistor comprises crystalline silicon.

6. The display device according to claim 2, wherein the pixel electrode is in contact with the insulating film.

7. The display device according to claim 2, further comprising a liquid crystal over the pixel electrode.

8. A display device comprising:

a first thin film transistor comprising a gate electrode over a substrate, an insulating film formed over the gate electrode, a first semiconductor film formed over the insulating film, a pair of second semiconductor films formed over the first semiconductor film, and a pair of electrodes over the pair of second semiconductor films;

an inorganic insulating film over the first thin film transistor;

a pixel electrode in electrical contact with one of the pair of electrodes;

a gate wiring between the substrate and the insulating film, wherein the gate wiring is continuous to the gate electrode;

a source wiring being continuous to the other of the pair of electrodes, the source wiring comprising a conductive layer and extending across the gate wiring;

a third semiconductor film extending along and below the source wiring, the third semiconductor film being continuous to the first semiconductor film;

a fourth semiconductor film between the third semiconductor film and the source wiring, the fourth semiconductor film extending along the source wiring and being continuous to one of the pair of second semiconductor films; and

a driver circuit electrically connected to the source wiring, the driver circuit comprising a second transistor provided over the substrate.

9. The display device according to claim 8, wherein the inorganic insulating film comprises silicon and nitrogen.

10. The display device according to claim 8, wherein the inorganic insulating film is positioned between the first thin film transistor and the pixel electrode.

11. The display device according to claim 8, wherein a channel forming region of the first thin film transistor comprises amorphous silicon.

12. The display device according to claim 8, wherein the second transistor is a thin film transistor formed on a second substrate.

13. The display device according to claim 8, wherein a channel forming region of the second transistor comprises crystalline silicon.

14. The display device according to claim 8, wherein the pixel electrode is in contact with the insulating film.

15. The display device according to claim 8, further comprising a liquid crystal over the pixel electrode.