Semiconductor device

• US 9,362,412 B2
• Filed: 08/26/2013
• Issued: 06/07/2016
• Est. Priority Date: 03/27/2009
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Umezaki, Atsushi
• Primary Examiner(s): MA, CALVIN
• Application Number:
  US13/975,422
• Publication Number:
  US 20130334527A1
• Time in Patent Office: 1,016 Days
• Field of Search: 345/87, 345/92, 345/98, 345/100, 345/205, 345/690
• US Class Current: 1/1
• CPC Class Codes: G09G 2300/04 Structural and physical details of display devices
• CPC Class Codes: G09G 2310/0275 Details of drivers for data electrodes, other than drivers for liquid crystal, plasma or OLED displays, not related to handling digital grey scale data or to communication of data to the pixels by means of a current
• CPC Class Codes: G09G 3/20 for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence
• CPC Class Codes: G11C 19/28 using semiconductor elements G11C19/14, G11C19/36 take precedence
• CPC Class Codes: H01L 21/477 Thermal treatment for modifying the properties of semiconductor bodies, e.g. annealing, sintering H01L21/38 - H01L21/449 and H01L21/461 - H01L21/475 take precedence
• CPC Class Codes: H01L 27/1255 integrated with passive devices, e.g. auxiliary capacitors
• CPC Class Codes: H01L 27/127 with a particular formation, treatment or patterning of the active layer specially adapted to the circuit arrangement
• CPC Class Codes: H01L 29/7869 having a semiconductor body comprising an oxide semiconductor material, e.g. zinc oxide, copper aluminium oxide, cadmium stannate

Abstract

One of the objects is to improve display quality by reduction in malfunctions of a circuit. In a driver circuit formed using a plurality of pulse output circuits having first to third transistors and first to fourth signal lines, a first clock signal is supplied to the first signal line; a preceding stage signal is supplied to the second signal line; a second clock signal is supplied to the third signal line; an output signal is output from the fourth signal line. Duty ratios of the first clock signal and the second clock signal are different from each other. A period during which the second clock signal is changed from an L-level signal to an H-level signal after the first clock signal is changed from an H-level signal to an L-level signal is longer than a period during which the preceding stage signal is changed from an L-level signal to an H-level signal.

Claims

1. A semiconductor device comprising:

a driver circuit comprising a plurality of pulse output circuits each comprising a first transistor, a second transistor and a third transistor, wherein each of the first transistor, the second transistor and the third transistor includes a channel portion including an oxide semiconductor,

wherein a first terminal of the first transistor is directly connected to a first signal line,

wherein a second terminal of the first transistor is directly connected to a third signal line,

wherein a gate of the second transistor and a first terminal of the second transistor are directly connected to a second signal line,

wherein a gate of the first transistor, a second terminal of the second transistor, and a first terminal of the third transistor are directly connected to each other,

wherein a second terminal of the third transistor is directly connected to the second signal line, and

wherein a gate of the third transistor is directly connected to a fourth signal line.

2. The semiconductor device according to claim 1, wherein the first transistor, the second transistor and the third transistor have the same polarity.

3. The semiconductor device according to claim 1, wherein each of the first transistor, the second transistor and the third transistor is a thin film transistor.

4. The semiconductor device according to claim 1, wherein the oxide semiconductor is one of ZnO, InGaZnO, indium zinc oxide, indium tin oxide, SnO, TiO, and AlZnSnO.

5. An electronic device comprising the semiconductor device according to claim 1 and an operation switch.

6. The semiconductor device according to claim 1, wherein a second terminal of the third transistor is directly connected to the second signal line.

7. The semiconductor device according to claim 1, wherein the oxide semiconductor is InGaZnO.

8. The semiconductor device according to claim 1, further comprising:

a pixel portion, wherein a signal output from the driver circuit is input to the pixel portion.

9. A semiconductor device comprising:

a driver circuit comprising a plurality of pulse output circuits each comprising a first transistor, a second transistor and a third transistor, wherein each of the first transistor, the second transistor and the third transistor includes a channel portion including a first oxide semiconductor,

a pixel portion comprising a fourth transistor that includes a channel portion including a second oxide semiconductor, wherein a signal output from the driver circuit is input to the pixel portion,

wherein a first terminal of the first transistor is directly connected to a first signal line,

wherein a second terminal of the first transistor is directly connected to a third signal line,

wherein a gate of the second transistor and a first terminal of the second transistor are directly connected to a second signal line,

wherein a gate of the first transistor, a second terminal of the second transistor, and a first terminal of the third transistor are directly connected to each other,

wherein a second terminal of the third transistor is directly connected to the second signal line, and

wherein a gate of the third transistor is directly connected to a fourth signal line.

10. The semiconductor device according to claim 9, wherein the first transistor, the second transistor, the third transistor, and the fourth transistor have the same polarity.

11. The semiconductor device according to claim 9, wherein each of the first transistor, the second transistor, the third transistor, and the fourth transistor is a thin film transistor.

12. The semiconductor device according to claim 9, wherein each of the first oxide semiconductor and the second oxide semiconductor is one of ZnO, InGaZnO, indium zinc oxide, indium tin oxide, SnO, TiO, and AlZnSnO.

13. An electronic device comprising the semiconductor device according to claim 9 and an operation switch.

14. The semiconductor device according to claim 9, wherein a second terminal of the third transistor is directly connected to the second signal line.

15. The semiconductor device according to claim 9, wherein each of the first oxide semiconductor and the second oxide semiconductor is InGaZnO.

16. A semiconductor device comprising:

a first transistor, a second transistor and a third transistor, wherein each of the first transistor, the second transistor, and the third transistor includes a channel portion including an oxide semiconductor,

wherein a gate of the second transistor, a first terminal of the second transistor, and a second terminal of the third transistor are directly connected to each other, and

wherein a gate of the first transistor, a second terminal of the second transistor, and a first terminal of the third transistor are directly connected to each other.

17. The semiconductor device according to claim 16, wherein each of the first transistor, the second transistor, and the third transistor is a thin film transistor.

18. The semiconductor device according to claim 16, wherein the oxide semiconductor is InGaZnO.