Method for manufacturing semiconductor device
First Claim
1. A method for manufacturing a display device comprising the steps of:
- forming a gate insulating film over a gate electrode;
forming an oxide semiconductor layer over the gate insulating film;
performing a heat treatment at a temperature higher than or equal to 400°
C. on the oxide semiconductor layer and then cooling the oxide semiconductor layer in an atmosphere containing oxygen;
forming a source electrode and a drain electrode over the oxide semiconductor layer after the step of heating;
forming an oxide insulating film over the gate insulating film, the oxide semiconductor layer, the source electrode, and the drain electrode;
forming an insulating layer over the oxide insulating film; and
forming an electrode for a display element over the insulating layer, the electrode electrically connected to the source electrode or the drain electrode,wherein the oxide insulating film is in contact with part of the oxide semiconductor layer.
0 Assignments
0 Petitions
Accused Products
Abstract
An object is to manufacture a highly reliable semiconductor device including a thin film transistor with stable electric characteristics. In a method for manufacturing a semiconductor device including a thin film transistor in which an oxide semiconductor film is used for a semiconductor layer including a channel formation region, heat treatment (for dehydration or dehydrogenation) is performed to improve the purity of the oxide semiconductor film and reduce impurities including moisture or the like. After that, slow cooling is performed under an oxygen atmosphere. Besides impurities including moisture or the like exiting in the oxide semiconductor film, heat treatment causes reduction of impurities including moisture or the like exiting in a gate insulating layer and those in interfaces between the oxide semiconductor film and films which are provided over and below the oxide semiconductor and in contact therewith.
150 Citations
28 Claims
-
1. A method for manufacturing a display device comprising the steps of:
-
forming a gate insulating film over a gate electrode; forming an oxide semiconductor layer over the gate insulating film; performing a heat treatment at a temperature higher than or equal to 400°
C. on the oxide semiconductor layer and then cooling the oxide semiconductor layer in an atmosphere containing oxygen;forming a source electrode and a drain electrode over the oxide semiconductor layer after the step of heating; forming an oxide insulating film over the gate insulating film, the oxide semiconductor layer, the source electrode, and the drain electrode; forming an insulating layer over the oxide insulating film; and forming an electrode for a display element over the insulating layer, the electrode electrically connected to the source electrode or the drain electrode, wherein the oxide insulating film is in contact with part of the oxide semiconductor layer. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
-
8. A method for manufacturing a display device comprising the steps of:
-
forming a gate insulating film over a gate electrode; forming an oxide semiconductor layer over the gate insulating film; performing a heat treatment on the oxide semiconductor layer and then cooling the oxide semiconductor layer in an atmosphere containing oxygen; forming a source electrode and a drain electrode over the oxide semiconductor layer after the step of heating; forming an oxide insulating film over the gate insulating film, the oxide semiconductor layer, the source electrode, and the drain electrode; forming an insulating layer over the oxide insulating film; and forming an electrode for a display element over the insulating layer, the electrode electrically connected to the source electrode or the drain electrode, wherein the oxide insulating film is in contact with part of the oxide semiconductor layer, and wherein the oxide semiconductor layer after the step of heating includes crystals. - View Dependent Claims (9, 10, 11, 12, 13, 14)
-
-
15. A method for manufacturing a display device comprising the steps of:
-
forming a pixel portion and a driver circuit over a substrate, wherein each of the pixel portion and the driver circuit includes a transistor, wherein the transistor is manufactured by a process comprising the steps of; forming a gate electrode over the substrate; forming a gate insulating film over the gate electrode; forming an oxide semiconductor layer over the gate insulating film; performing a heat treatment at a temperature higher than or equal to 400°
C. on the oxide semiconductor layer and then cooling the oxide semiconductor layer in an atmosphere containing oxygen;forming a source electrode and a drain electrode over the oxide semiconductor layer after the step of heating; forming an oxide insulating film over the gate insulating film, the oxide semiconductor layer, the source electrode, and the drain electrode; and forming an insulating layer over the oxide insulating film, wherein the oxide insulating film is in contact with part of the oxide semiconductor layer. - View Dependent Claims (16, 17, 18, 19, 20, 21)
-
-
22. A method for manufacturing a display device comprising the steps of:
-
forming a pixel portion and a driver circuit over a substrate, wherein each of the pixel portion and the driver circuit includes a transistor, wherein the transistor is manufactured by a process comprising the steps of; forming a gate electrode over the substrate; forming a gate insulating film over the gate electrode; forming an oxide semiconductor layer over the gate insulating film; performing a heat treatment on the oxide semiconductor layer and then cooling the oxide semiconductor layer in an atmosphere containing oxygen; forming a source electrode and a drain electrode over the oxide semiconductor layer after the step of heating; forming an oxide insulating film over the gate insulating film, the oxide semiconductor layer, the source electrode, and the drain electrode; and forming an insulating layer over the oxide insulating film, wherein the oxide insulating film is in contact with part of the oxide semiconductor layer, and wherein the oxide semiconductor layer after the step of heating includes crystals. - View Dependent Claims (23, 24, 25, 26, 27, 28)
-
Specification