E-BOOK READER

• US 20160118412A1
• Filed: 12/28/2015
• Published: 04/28/2016
• Est. Priority Date: 10/21/2009
• Status: Abandoned Application

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: YAMAZAKI, Shunpei, UMEZAKI, Atsushi
• Application Number:
  US14/980,952
• Publication Number:
  US 20160118412A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: G06F 3/0483 Interaction with page-structured environments, e.g. book metaphor
• CPC Class Codes: G09G 2330/02 Details of power systems and of start or stop of display operation
• CPC Class Codes: G09G 2330/021 Power management, e.g. power saving
• CPC Class Codes: G09G 3/344 based on particles moving in a fluid or in a gas, e.g. electrophoretic devices electrophoretic devices per se G02F1/167
• CPC Class Codes: H01L 27/1225 with semiconductor materials not belonging to the group IV of the periodic table, e.g. InGaZnO
• 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 29/7869 having a semiconductor body comprising an oxide semiconductor material, e.g. zinc oxide, copper aluminium oxide, cadmium stannate

Abstract

An e-book reader including a display panel having a thin film transistor with stable electrical characteristics is provided. Alternatively, an e-book reader capable of holding images for a long time is provided. Alternatively, a high-resolution e-book reader is provided. Alternatively, an e-book reader with low power consumption is provided. Display on the display panel of the e-book reader is controlled by a thin film transistor whose channel formation region is formed using an oxide semiconductor which is an intrinsic or substantially intrinsic semiconductor by removal of an impurity that might be an electron donor in the oxide semiconductor and has a larger energy gap than a silicon semiconductor.

Claims

1. (canceled)

2. A display device comprising a pixel, the pixel comprising:

a first conductive layer over a substrate;

a first insulating layer over the first conductive layer;

an oxide semiconductor layer over the first insulating layer;

a second conductive layer over a portion of the oxide semiconductor layer;

a third conductive layer over a portion of the oxide semiconductor layer;

a second insulating layer over the oxide semiconductor layer, the second conductive layer and the third conductive layer;

a fourth conductive layer electrically connected to the second conductive layer;

a fifth conductive layer electrically connected to the third conductive layer; and

a sixth conductive layer over the second insulating layer,

wherein the first conductive layer includes a region configured to be a first gate electrode, and the sixth conductive layer includes a region configured to be a second gate electrode, and

wherein the sixth conductive layer contains a light-transmitting conductive oxide.

3. The display device according to claim 2, wherein the first conductive layer has substantially a same potential as the sixth conductive layer.

4. The display device according to claim 2, wherein the oxide semiconductor layer has a carrier concentration of 5×

10¹⁴/cm³ or lower.

5. The display device according to claim 2, wherein the oxide semiconductor layer has an energy gap of 2 eV or higher.

6. The display device according to claim 2, wherein the display device is incorporated in an e-book reader.

7. A display device comprising a pixel, the pixel comprising:

a first conductive layer over a substrate;

a first insulating layer over the first conductive layer;

an oxide semiconductor layer over the first insulating layer;

a second conductive layer over a portion of the oxide semiconductor layer;

a third conductive layer over a portion of the oxide semiconductor layer;

a second insulating layer over the oxide semiconductor layer, the second conductive layer and the third conductive layer;

a fourth conductive layer electrically connected to the second conductive layer;

a fifth conductive layer electrically connected to the third conductive layer; and

a sixth conductive layer over the second insulating layer,

wherein the first conductive layer includes a region configured to be a first gate electrode, and the sixth conductive layer includes a region configured to be a second gate electrode,

wherein the sixth conductive layer contains a light-transmitting conductive oxide, and

wherein the fourth conductive layer, the fifth conductive layer and the sixth conductive layer are provided over and in contact with the second insulating layer.

8. The display device according to claim 7, wherein the first conductive layer has substantially a same potential as the sixth conductive layer.

9. The display device according to claim 7, wherein the oxide semiconductor layer has a carrier concentration of 5×

10¹⁴/cm³ or lower.

10. The display device according to claim 7, wherein the oxide semiconductor layer has an energy gap of 2 eV or higher.

11. The display device according to claim 7, wherein the display device is incorporated in an e-book reader.