Electro-optical device

• US 5,383,041 A
• Filed: 08/12/1993
• Issued: 01/17/1995
• Est. Priority Date: 12/20/1990
• Status: Expired due to Term

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Mase, Akira, Yamazaki, Shunpei
• Primary Examiner(s): Sikes, William L.
• Assistant Examiner(s): MAI, HUY KIM
• Application Number:
  US08/104,935
• Time in Patent Office: 523 Days
• Field of Search: 359/54, 359/59, 359/85, 359/51, 359/52, 340/784
• US Class Current: 349/43
• CPC Class Codes: G02F 1/13624 having more than one switching element per pixel
• CPC Class Codes: G02F 1/136245 having complementary transistors
• 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 29/78696 characterised by the structure of the channel, e.g. multichannel, transverse or longitudinal shape, length or width, doping structure, or the overlap or alignment between the channel and the gate, the source or the drain, or the contacting structure of the channel H01L29/78612 takes precedence; transistors having a drain offset region or a lightly doped drain [LDD] H01L29/78621

Abstract

An electro-optical device is disclosed. The electro-optical device comprises pixels arranged in rows and columns. Each pixel comprises at least one complementary TFT (thin film transistor) pair. Each complementary TFT pair consists of an n-channel TFT and a p-channel TFT. The gates of the complementary TFTs of each pixel are all connected to a signal line extending in the Y-direction. The input terminals of the TFTs of each pixel are connected to a pair of signal lines extending in the X-direction. Each pixel has at least one pixel electrode connected to the outputs of the TFTs thereof. In the operation of the electro-optical device, an electric signal is applied to the pair of signal lines extending in the X-direction and an electric signal is applied to the signal line extending in the Y-direction for the duration of the electric signal applied to the pair of signal lines extending in the X-direction.

Claims

1. An electro-optical device comprising:

a pair of substrates at least one of which is transparent;

an electro-optical modulating layer disposed between said substrates; and

at least two pixels,

wherein one of said two pixels is provided with complementary transistors comprising an n-channel transistor and a p-channel transistor provided on an inside of one of said substrates;

an electrode provided on said inside of one of said substrates and connected to one of drain and source terminals of said n-channel transistor and one of drain and source terminals of said p-channel transistor;

a pair of row control lines one of which is connected to the other one of the drain and source terminals of said n-channel transistor and the other one of which is connected to the other one of the drain and source terminals of said p-channel transistor; and

a column control line connected to gate terminals of said n-channel transistor and said p-channel transistor,

wherein another one of said two pixels is provided with other complementary transistors comprising another n-channel transistor and another p-channel transistor provided on said inside of one of said substrates;

another electrode provided on said inside of one of said substrates and connected to one of drain and source terminals of said another n-channel transistor and one of drain and source terminals of said another p-channel transistor; and

another pair of row control lines one of which is connected to the other one of the drain and source terminals of said another n-channel transistor and the other one of which is connected to the other one of the drain and source terminals of said another p-channel transistor,

wherein gate terminals of said another n-channel transistor and said another p-channel transistor are connected to said column control line and the row control line connected to the other one of the drain and source terminals of said n-channel transistor of said one of said two pixels is adjacent to the row control line connected to the other one of the drain and source terminals of said another n-channel transistor.

2. The electro-optical device of claim 1 wherein the row control line connected to the other one of the drain and source terminals of said another n-channel transistor is separate from the row control line adjacent thereto.

3. The electro-optical device of claim 1 wherein said electro-optical modulating layer comprises a transparent solid and a material comprising a liquid crystal and said material comprising a liquid crystal is dispersed in said transparent solid in the form of granules.

4. The electro-optical device of claim 1 wherein said electro-optical modulating layer comprises a liquid crystal selected from the group consisting of a ferroelectric liquid crystal, a polymer liquid crystal, a liquid crystal for use in twisted nematic type liquid crystal device, a liquid crystal for use in dispersion type liquid crystal device, a liquid crystal for use in guest-host type liquid crystal device, and a liquid crystal for use in phase-transition type liquid crystal device.

5. The electro-optical device of claim 1 wherein said two pixels are adjacent to each other.

6. An electro-optical device comprising:

a pair of substrates at least one of which is transparent;

an electro-optical modulating layer disposed between said substrates; and

at least two pixels,

wherein one of said two pixels is provided with complementary transistors comprising an n-channel transistor and a p-channel transistor provided on an inside of one of said substrates;

an electrode provided on said inside of one of said substrates and connected to one of drain and source terminals of said n-channel transistor and one of drain and source terminals of said p-channel transistor;

a pair of row control lines one of which is connected to the other one of the drain and source terminals of said n-channel transistor and the other one of which is connected to the other one of the drain and source terminals of said p-channel transistor; and

a column control line connected to gate terminals of said n-channel transistor and said p-channel transistor,

wherein another one of said two pixels is provided with other complementary transistors comprising another n-channel transistor and another p-channel transistor provided on said inside of one of said substrates;

another electrode provided on said inside of one of said substrates and connected to one of drain and source terminals of said another n-channel transistor and one of drain and source terminals of said another p-channel transistor; and

another pair of row control lines one of which is connected to the other one of the drain and source terminals of said another n-channel transistor and the other one of which is connected to the other one of the drain and source terminals of said another p-channel transistor;

wherein gate terminals of said another n-channel transistor and said another p-channel transistor are connected to said column control line and the row control line connected to the other one of the drain and source terminals of said p-channel transistor of said one of said two pixels is adjacent to the row control line connected to the other one of the drain and source terminals of said another p-channel transistor.

7. The electro-optical device of claim 6 wherein the row control line connected to the other one of the drain and source terminals of said another p-channel transistor is separate from the row control line adjacent thereto.

8. The electro-optical device of claim 6 wherein said electro-optical modulating layer comprises a transparent solid and a material comprising a liquid crystal and said material comprising a liquid crystal is dispersed in said transparent solid in the form of granules.

9. The electro-optical device of claim 6 wherein said electro-optical modulating layer comprises a liquid crystal selected from the group consisting of a ferroelectric liquid crystal, a polymer liquid crystal, a liquid crystal for use in twisted nematic type liquid crystal device, a liquid crystal for use in dispersion type liquid crystal device, a liquid crystal for use in guest-host type liquid crystal device, and a liquid crystal for use in phase-transition type liquid crystal device.

10. The electro-optical device of claim 6 wherein said two pixels are adjacent to each other.

11. An active matrix display device comprising:

a light modulating layer having a plurality of pixels wherein each said pixel is provided with at least two pixel electrodes and at least two thin film semiconductor devices formed on a substrate, with one connected to each of said pixel electrodes;

an electrode arrangement comprising a plurality of column lines and a plurality of row lines; and

a peripheral circuit comprising a plurality of thin film transistors formed on said substrate, where a channel semiconductor layer of each of said transistors has a crystalline structure,

wherein the thin film semiconductor devices associated with each pixel are connected to one of said column lines in common.

12. The device of claim 11 wherein each of the thin film semiconductor devices associated with one of said pixels is connected to one of said row lines, individually.

13. The device of claim 11 wherein said thin film semiconductor devices associated with each said pixel comprise at least a pair of transistors, said pair including a p-channel transistor and an n-channel transistor.

14. The device of claim 11 wherein said light modulating layer comprises a liquid crystal.

15. The device of claim 14 wherein said liquid crystal is a polymer-dispersed liquid crystal.

16. An active matrix display device comprising:

a glass substrate;

a plurality of pairs of pixel electrodes formed on said substrate, each pair constituting one pixel;

a plurality of thin film semiconductor devices formed on said substrate, with one connected to each of said pixel electrodes;

a peripheral circuit comprising thin film transistors formed on said substrate,

wherein said thin film transistors of said peripheral circuit include channel semiconductor layers having at least one of an electron mobility of 15-300 cm² /V·

s and a hole mobility of 10-200 cm² /V·

s.

17. The device of claim 16 wherein said channel semiconductor layers comprise silicon in which oxygen is contained at a concentration not higher than 7×

10¹⁹ atoms/cm³.

18. An active matrix display device comprising:

a glass substrate;

a plurality of pairs of pixel electrodes formed on said substrate, each pair constituting one pixel;

a plurality of this film semiconductor devices formed on said substrate, with one connected to each of said pixel electrodes;

a peripheral circuit comprising thin film transistors formed on said substrate,

wherein said thin film transistors of said peripheral circuit have a channel semiconductor layer comprising silicon in which oxygen is contained at a concentration not higher than 7×

10¹⁹ atoms/cm³.