Organic light emitting diode display, driving method thereof, and manufacturing method thereof

Patent metadata

Field	Value
Publication number	US-2016012775-A1
Application number	US-201414542900-A
Country	US
Kind code	A1
Filing date	Nov 17, 2014
Priority date	Jul 10, 2014
Publication date	Jan 14, 2016
Grant date	—

Abstract

An organic light emitting diode display includes a semiconductor pattern which includes a plurality of channel regions. A first gate insulating layer is on the semiconductor pattern, a first gate conductive layer is on the first gate insulating layer, a second gate insulating layer is on the first gate conductive layer, and a second gate conductive layer is on the second gate insulating layer. The channel regions include a first channel region that overlaps the first gate conductive layer and a second channel region that does not overlap the first gate conductive layer. The first channel region and the second channel region have different doping concentrations.

First claim

What is claimed is:

1 . An organic light emitting diode display, comprising:
a substrate; a semiconductor pattern on the substrate and including channel regions; a first gate insulating layer on the semiconductor pattern; a first gate conductive layer on the first gate insulating layer; a second gate insulating layer on the first gate conductive layer; and a second gate conductive layer on the second gate insulating layer, wherein the channel regions include a first channel region that overlaps the first gate conductive layer and a second channel region that does not overlap the first gate conductive layer, and wherein the first channel region and the second channel region have different doping concentrations.

2 . The display as claimed in claim 1 , wherein the second gate conductive layer overlaps each of the channel regions.

3 . The display as claimed in claim 2 , wherein:
the first channel region includes a driving channel region in a driving transistor and a first switching channel region in a first switching transistor, the second channel region includes a second switching channel region in a second switching transistor, and the first switching transistor and the second switching transistor have different threshold voltages.

4 . The display as claimed in claim 3 , wherein the first gate conductive layer and the second gate conductive layer that respectively overlap the driving channel region form a storage capacitor along with the second gate insulating layer.

5 . The display as claimed in claim 4 , wherein the first gate conductive layer overlapping the driving channel region receives a driving voltage.

6 . The display as claimed in claim 5 , wherein the first gate conductive layer overlapping the first channel region has substantially an island shape.

7 . The display as claimed in claim 6 , wherein the first switching transistor includes a source electrode coupled to a drain electrode of the driving transistor.

8 . An organic light emitting diode display, comprising:
a driving transistor including a driving gate electrode coupled to a storage capacitor; a first switching transistor including a first source electrode coupled to a driving drain electrode of the driving transistor; and a second switching transistor including a second drain electrode coupled to a driving source electrode of the driving transistor, wherein a second source electrode of the second switching transistor receives a driving voltage, and wherein a channel region of the first switching transistor and a channel region of the second switching transistor have different doping concentrations.

9 . The display as claimed in claim 8 , wherein the doping concentrations of the channel region of the first switching transistor and a channel region of the driving transistor are substantially equal.

10 . The display as claimed in claim 9 , further comprising:
a first gate conductive layer including a portion between a gate electrode of the first switching transistor and the channel region of the first switching transistor.

11 . The display as claimed in claim 10 , wherein the first gate conductive layer includes a portion between the driving gate electrode of the driving transistor and the channel region of the driving transistor.

12 . A method for manufacturing an organic light emitting diode display, the method comprising:
forming a semiconductor pattern layer by laminating and then patterning a semiconductor layer on a substrate; forming a first gate insulating layer on the semiconductor pattern layer; forming a first gate conductive layer on the first gate insulating layer; forming first and second channel regions having different doping concentrations by doping the semiconductor pattern layer with an impurity after forming the first gate conductive layer; forming a second gate insulating layer on the first gate conductive layer; forming a second gate conductive layer on the second gate insulating layer; and forming a portion of the semiconductor pattern layer as a conductive region by doping the semiconductor pattern with an impurity after forming the second gate conductive layer.

13 . The method as claimed in claim 12 , wherein:
the first channel region overlaps the first gate conductive layer, and the second channel region does not overlap the first gate conductive layer.

14 . The method as claimed in claim 13 , wherein the second gate conductive layer overlaps the first and second channel regions.

15 . The method as claimed in claim 14 , further comprising:
channel-doping the semiconductor pattern layer entirely by injecting an impurity before forming the first gate insulating layer and after forming the semiconductor pattern layer.

16 . The method as claimed in claim 15 , further comprising:
forming an interlayer insulating layer on the second gate conductive layer; and forming a data conductive layer on the interlayer insulating layer.

17 . A method for driving an organic light emitting diode (OLED) display, the method comprising:
applying a driving voltage to a source electrode of a driving transistor, by turning off a switching transistor and a compensation transistor and turning on an initialization transistor, an operation control transistor, and a light emission control transistor; applying an initialization voltage to a gate electrode of the driving transistor, by turning on the initialization transistor and turning off the switching transistor, the compensation transistor, the operation control transistor, and the light emission control transistor; applying a data signal to the source electrode of the driving transistor, by turning off the initialization transistor, the operation control transistor, the light emission control transistor, and a bypass transistor and turning on the switching transistor and the compensation transistor; and controlling an OLED to emit light with luminance corresponding to the data signal, by turning off the switching transistor, the compensation transistor, the initialization transistor, and the bypass transistor and turning on the operation control transistor and the light emission control transistor, wherein applying the driving voltage includes turning off the light emission control transistor earlier than the operation control transistor, and wherein a threshold voltage of the light emission control transistor is different from that of the operation control transistor.

18 . The method as claimed in claim 17 , wherein a channel region of the light emission control transistor and a channel region of the operation control transistor have different doping concentrations.

19 . The method as claimed in claim 18 , wherein the light emission control transistor and the operation control transistor are controlled by a same signal.

20 . The method as claimed in claim 19 , wherein the bypass transistor is coupled between a source electrode of the initialization transistor and a drain electrode of the light emission control transistor, and wherein the bypass transistor and the switching transistor are controlled by a same signal.

Assignees

• Samsung Display Co Ltd

Inventors

• Jeong Cheol Yun
• Choi Jong Hyun

Classifications

• H10D30/674

  characterised by the active materials · CPC title

• H10D30/6757

  characterised by the structure of the channel, e.g. transverse or longitudinal shape or doping profile (TFTs having channel structures for preventing kink or snapback effects H10D30/6708; TFTs having lightly-doped source or drain extensions H10D30/6715) · CPC title

• H10K71/00

  Manufacture or treatment specially adapted for the organic devices covered by this subclass · CPC title

• H10D86/481

  integrated with passive devices, e.g. auxiliary capacitors · CPC title

• H10D86/0212

  comprising manufacture, treatment or coating of substrates · CPC title