US 8,552,423 B2Granted

Semiconductor device and method for manufacturing semiconductor device

AssigneeSemiconductor Energy Laboratory Co., Ltd.

InventorsShunpei Yamazaki, Junichiro Sakata, Hiroyuki Miyake, Hideaki Kuwabara, Tatsuya Takahashi

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Abstract

An aperture ratio of a semiconductor device is improved. A driver circuit and a pixel are provided over one substrate, and a first thin film transistor in the driver circuit and a second thin film transistor in the pixel each include a gate electrode layer, a gate insulating layer over the gate electrode layer, an oxide semiconductor layer over the gate insulating layer, source and drain electrode layers over the oxide semiconductor layer, and an oxide insulating layer in contact with part of the oxide semiconductor layer over the gate insulating layer, the oxide semiconductor layer, and the source and drain electrode layers. The gate electrode layer, the gate insulating layer, the oxide semiconductor layer, the source and drain electrode layers, and the oxide insulating layer of the second thin film transistor each have a light-transmitting property.

Claims20

Dependent claims

A semiconductor device comprising:

a driver circuit including a first transistor over a substrate;
and
a pixel including a second transistor over the substrate,
wherein the first transistor and the second transistor each comprise:
a first gate electrode layer;
a gate insulating layer over the first gate electrode layer;
an oxide semiconductor layer over the gate insulating layer;
a source electrode layer over the oxide semiconductor layer;
a drain electrode layer over the oxide semiconductor layer;
and
an oxide insulating layer over the gate insulating layer, the oxide semiconductor layer, the source electrode layer, and the drain electrode layer, the oxide insulating layer being in contact with at least a channel formation region in the oxide semiconductor layer,
wherein the channel formation region overlaps with the first gate electrode layer with the gate insulating layer therebetween,
wherein, in the second transistor, each of the first gate electrode layer, the gate insulating layer, the oxide semiconductor layer, the source electrode layer, the drain electrode layer, and the oxide insulating layer has a light-transmitting property,
wherein the first transistor further comprises a second gate electrode layer overlapping with the first gate electrode layer,
wherein the pixel further comprises a pixel electrode electrically connected to one of the source electrode layer and the drain electrode layer of the second transistor, and
wherein the pixel electrode overlaps with all of the oxide semiconductor layer of the second transistor.

13 more elements

A semiconductor device comprising:

a driver circuit including a transistor over a substrate,
wherein the transistor comprises:
a first gate electrode layer;
a gate insulating layer over the first gate electrode layer;
an oxide semiconductor layer over the gate insulating layer;
a source electrode layer over the oxide semiconductor layer;
a drain electrode layer over the oxide semiconductor layer;
an oxide insulating layer over the gate insulating layer, the oxide semiconductor layer, the source electrode layer, and the drain electrode layer, the oxide insulating layer being in contact with at least a channel formation region in the oxide semiconductor layer;
and
a second gate electrode layer overlapping with the first gate electrode layer,
wherein the channel formation region overlaps with the first gate electrode layer with the gate insulating layer therebetween,
wherein the oxide semiconductor layer includes an end portion in a channel length direction and a region overlapping with the source electrode layer or the drain electrode layer, and
wherein a thickness of the end portion of the oxide semiconductor layer is thinner than a thickness of the region of the oxide semiconductor layer.

10 more elements

A semiconductor device comprising:

a pixel including a transistor over a substrate,
wherein the transistor comprises:
a gate electrode layer;
a gate insulating layer over the gate electrode layer;
an oxide semiconductor layer over the gate insulating layer;
a source electrode layer over the oxide semiconductor layer;
a drain electrode layer over the oxide semiconductor layer;
and
an oxide insulating layer over the gate insulating layer, the oxide semiconductor layer, the source electrode layer, and the drain electrode layer, the oxide insulating layer being in contact with at least a channel formation region in the oxide semiconductor layer,
wherein the channel formation region overlaps with the gate electrode layer with the gate insulating layer therebetween,
wherein each of the gate electrode layer, the gate insulating layer, the oxide semiconductor layer, the source electrode layer, the drain electrode layer, and the oxide insulating layer has a light-transmitting property,
wherein the oxide semiconductor layer includes an end portion in a channel length direction and a region overlapping with the source electrode layer or the drain electrode layer, and
wherein a thickness of the end portion of the oxide semiconductor layer is thinner than a thickness of the region of the oxide semiconductor layer.

10 more elements

Dependencies are inferred from the claim text.

Facts

Application: 12/835,903Filed 14 Jul 2010
Priority: JP 2009-16959918 Jul 2009
Published: US 2011/0012112 A120 Jan 2011
Granted: 8 Oct 2013
Term ends: Not estimatedThe source records don’t support an estimate.

Classification14 codes

H10D 86/60
Characterised by multiple TFTs: wherein the TFTs are in active matrices
G02F 1/1368
Active matrix addressed cells: in which the switching element is a three-electrode device
H10D 30/6733
Characterised by the shapes, relative sizes or dispositions of the gate electrodes: multi-gate TFTs
H10D 30/674
Thin-film transistors [TFT]: characterised by the active materials