Organic el display device and manufacturing method therefor

Patent metadata

Field	Value
Publication number	US-2020388661-A1
Application number	US-201816768444-A
Country	US
Kind code	A1
Filing date	Mar 28, 2018
Priority date	Mar 28, 2018
Publication date	Dec 10, 2020
Grant date	—

Abstract

By using an a-Si layer with low electron mobility in a TFT for driving an organic EL display device, the present invention solves problems stemming from uneven laser irradiation and suppresses the occurrence of non-uniform color and luminance. In the present invention, a first conductor film (26a) forming a drain electrode and a second conductor film (25a) forming a source electrode are disposed such that respective portions (26a1 . . . , 25a1 . . . ) of the first conductor film (26a) and the second conductor film (25a) are arranged in an alternating manner along a prescribed direction.

First claim

1 . An organic EL display apparatus comprising:
a substrate having a surface on which a drive circuit comprising a thin film transistor for driving a light emitting element is formed, a planarizing layer to planarize the surface of the substrate by covering the drive circuit, and an organic light emitting element, the organic light emitting element comprising a first electrode being formed on a surface of the planarizing layer and connected to the drive circuit, an organic light emitting layer being formed on the first electrode, and a second electrode being formed on the organic light emitting layer, wherein the thin film transistor for driving comprises a gate electrode, a drain electrode, a source electrode, and a semiconductor layer to be a channel of the thin film transistor for driving and has a stack structure of the gate electrode, the semiconductor layer, and a first conductor layer and a second conductor layer, the first conductor layer to make up the drain electrode being formed in connection with the semiconductor layer and the second conductor layer to make up the source electrode being formed in connection with the semiconductor layer; wherein the first conductor layer and the second conductor layer are arranged such that portions of each of the first conductor layer and the second conductor layer are lined up alternately in a predetermined direction; wherein the channel is the semiconductor layer being sandwiched between a portion of the first conductor layer and a portion of the second conductor layer, the portion of the first conductor layer and a portion of the second conductor layer neighboring each other; wherein the channel comprises a plurality of regions, each of the regions being sandwiched between the portion of the first conductor layer and the portion of the second conductor layer neighboring each other, and the semiconductor layer comprises an amorphous semiconductor, and, when a sum of the plurality of the lengths of a part at which the portion of the first conductor layer and the portion of the second conductor layer oppose is W, and an interval between the portion of the first conductor layer and the portion of the second conductor layer neighboring each other is L, W/L is greater than or equal to 50 and less than or Equal to 500; and wherein the planarizing layer being formed on the thin film transistor for driving is a stack structure comprising a first inorganic insulating layer and an organic insulating layer and a surface of the organic insulating layer is formed to greater than or equal to 20 nm and no greater than 50 nm in arithmetic average roughness Ra.

2 . The organic EL display apparatus according to claim 1 , wherein each of the first conductor layer and the second conductor layer is formed in a comb in a planer shape and comb-tooth portions of each of the first conductor layer and the second conductor layer are formed such that they engage with each other.

3 . (canceled)

4 . The organic EL display apparatus according to claim 1 , wherein a light emitting region of the light emitting element is formed in a rectangular shape and the thin film transistor for driving is formed in an under layer of the light emitting region and a part at which the portion of the first conductor layer and the portion of the second conductor layer oppose is formed along a longer side of the rectangular shape.

5 . The organic EL display apparatus according to claim 1 , wherein the gate electrode is formed over the entire range of a length of a plurality of parts at which the portion of the first conductor layer and the portion of the second conductor layer oppose, the portion of the first conductor layer and the portion of the second conductor layer neighboring each other.

6 . (canceled)

7 . The organic EL display apparatus according to claim 1 , wherein the planarizing layer is formed in a three-layer structure by a second insulating layer being formed on the organic insulating layer; and
a contact hole to electrically connect the organic light emitting element and the thin film transistor for driving is formed without a stepped portion in the three-layer structure.

8 . A method of manufacturing an organic EL display apparatus, the method comprising:
forming a drive circuit on a substrate, the drive circuit comprising a thin film transistor for driving a light emitting element; forming, on a surface of the drive circuit, a planarizing layer comprising a stack structure of a first inorganic insulating layer and an organic insulating layer; polishing a surface of the organic insulating layer by CMP; forming a contact hole in the organic insulating layer and the first inorganic insulating layer, the contact hole to reach the thin film transistor for driving; embedding a metal at an interior of the contact hole and forming a first electrode at a given region; forming an organic light emitting layer on the first electrode; and forming a second electrode on the organic light emitting layer, wherein the thin film transistor for driving comprises a gate electrode, a gate insulating layer, a drain electrode, a source electrode and a semiconductor layer to be a channel of the thin film transistor for driving and is formed with a stack structure comprising the gate electrode, the semiconductor layer, a first conductor layer to make up a drain electrode being formed in connection with the semiconductor layer, and a second conductor layer to make up the source electrode being formed in connection with the semiconductor layer; wherein the first conductor layer and the second conductor layer are formed such that portions of the first conductor layer and the second conductor layer are alternately lined up in a predetermined direction; wherein the channel is the semiconductor layer being sandwiched between a portion of the first conductor layer and a portion of the second conductor layer, the portion of the first conductor layer and the portion of the second conductor layer neighboring each other, wherein the channel comprises a plurality of regions, each of the regions being sandwiched between the portion of the first conductor layer and the portion of the second conductor layer neighboring each other, and the semiconductor layer comprises an amorphous semiconductor, and, when a sum of the plurality of the lengths of a part at which the portion of the first conductor layer and the portion of the second conductor layer oppose is W, and an interval between the portion of the first conductor layer and the portion of the second conductor layer neighboring each other is L, W/L is greater than or equal to 50 and less than or equal to 500; and wherein a surface of the organic insulating layer of the planarizing layer being formed on the thin film transistor for driving is formed to greater than or equal to 20 nm and no greater than 50 nm in arithmetic average roughness Ra.

9 . The method of manufacturing an organic EL display apparatus according to claim 8 , wherein forming the thin film transistor for driving comprises:
forming the gate electrode extending along the predetermined direction on the substrate; forming the gate insulating layer on the gate electrode; forming the semiconductor layer being amorphous on the gate insulating layer so as to cover the gate electrode along the predetermined direction; and forming the first conductor layer having a plurality of first portions being connected to the semiconductor layer and extending along a direction to cross the predetermined direction and the second conductor layer having a plurality of second portions being connected to the semiconductor layer and extending along a direction to cross the predetermined direction such that the first portions and the second portions ar

Assignees

• Sakai Display Products Corp

Inventors

• Kishimoto Katsuhiko
• Nishioka Yukiya

Classifications

• H10D86/60

  wherein the TFTs are in active matrices · CPC title

• H10D86/40

  characterised by multiple TFTs · CPC title

• H10D30/673

  characterised by the shapes, relative sizes or dispositions of the gate electrodes · CPC title

• H10D30/6729

  characterised by the electrodes · CPC title

• H10D86/451

  characterised by the compositions or shapes of the interlayer dielectrics · CPC title