Light-emitting device and method for manufacturing the same

A light-emitting device comprising:

• a driver circuit portion over a substrate, comprising:
• a first transistor comprising:
• a first gate electrode layer over the substrate;
• a gate insulating layer over the first gate electrode layer;
• a first oxide semiconductor layer over the gate insulating layer;
• a first source electrode layer over the first oxide semiconductor layer;
• and
• a first drain electrode layer over the first oxide semiconductor layer;
• and
• an oxide insulating layer over the first oxide semiconductor layer, the first source electrode layer, and the first drain electrode layer, the oxide insulating layer being in contact with at least a part of the first oxide semiconductor layer between the first source electrode layer and the first drain electrode layer;
• and
• a pixel portion over the substrate, comprising:
• a second transistor comprising:
• a second gate electrode layer;
• the gate insulating layer over the second gate electrode layer;
• a second oxide semiconductor layer over the gate insulating layer;
• a second source electrode layer over the second oxide semiconductor layer;
• and
• a second drain electrode layer over the second oxide semiconductor layer;
• the oxide insulating layer over the second oxide semiconductor layer, the second source electrode layer, and the second drain electrode layer, the oxide insulating layer being in contact with at least a part of the second oxide semiconductor layer between the second source electrode layer and the second drain electrode layer;
• a connection electrode layer over the oxide insulating layer and electrically connected to the second transistor;
• a first electrode layer over the oxide insulating layer;
• and electrically connected to the second transistor through the connection electrode layer;
• an EL layer over the first electrode layer;
• and
• a second electrode layer over the EL layer,
• wherein the first transistor comprises a conductive layer over the oxide insulating layer, the conductive layer overlapping with the first gate electrode layer and the first oxide semiconductor layer, and
• wherein the first and second gate electrode layers, the first and second source electrode layers, and the first and second drain electrode layers each comprise a metal conductive film.

A method for manufacturing a light-emitting device, comprising the steps of:

• forming a first gate electrode layer and a second gate electrode layer over a substrate;
• forming a gate insulating layer over the first gate electrode layer and the second gate electrode layer;
• forming over the gate insulating layer, a first oxide semiconductor layer so as to overlap with the first gate electrode layer, and a second oxide semiconductor layer so as to overlap with the second gate electrode layer;
• dehydrating or dehydrogenating the first oxide semiconductor layer and the second oxide semiconductor layer;
• forming a first source electrode layer and a first drain electrode layer comprising a metal conductive film over the first oxide semiconductor layer;
• forming a second source electrode layer and a second drain electrode layer comprising a metal conductive film over the second oxide semiconductor layer;
• forming an oxide insulating layer in contact with a part of the first oxide semiconductor layer and a part of the second oxide semiconductor layer over the first oxide semiconductor layer, the second oxide semiconductor layer, the first source electrode layer, the second source electrode layer, the first drain electrode layer, and the second drain electrode layer;
• forming a first electrode layer over the oxide insulating layer, the first electrode layer electrically connected to the second drain electrode layer;
• stacking an EL layer and a second electrode layer in this order over the first electrode layer;
• and
• forming a conductive layer over the oxide insulating layer, the conductive layer overlapping with the first gate electrode layer and the first oxide semiconductor layer, in the same step as the step of forming the first electrode layer.

A method for manufacturing a light-emitting device, comprising the steps of:

• forming a first gate electrode layer and a second gate electrode layer over a substrate;
• forming a gate insulating layer over the first gate electrode layer and the second gate electrode layer;
• forming over the gate insulating layer, a first oxide semiconductor layer so as to overlap with the first gate electrode layer, and a second oxide semiconductor layer so as to overlap with the second gate electrode layer;
• dehydrating or dehydrogenating the first oxide semiconductor layer and the second oxide semiconductor layer;
• forming a first source electrode layer and a first drain electrode layer comprising a metal conductive film over the first oxide semiconductor layer;
• forming a second source electrode layer and a second drain electrode layer comprising a metal conductive film over the second oxide semiconductor layer;
• forming an oxide insulating layer in contact with a part of the first oxide semiconductor layer and a part of the second oxide semiconductor layer over the first oxide semiconductor layer, the second oxide semiconductor layer, the first source electrode layer, the second source electrode layer, the first drain electrode layer, and the second drain electrode layer;
• forming a connection electrode layer over the oxide insulating layer;
• forming a first electrode layer over the oxide insulating layer so as to be electrically connected to the second drain electrode layer through the connection electrode layer;
• stacking an EL layer and a second electrode layer in this order over the first electrode layer;
• and
• forming a conductive layer over the oxide insulating layer, the conductive layer overlapping with the first gate electrode layer and the first oxide semiconductor layer, in the same step as the step of forming the connection electrode layer.