Patent ID: 8951849
Filing Date: 2015-02-10
Classification: H01L

Abstract:
1. A method for manufacturing a semiconductor device, comprising: forming a gate electrode over a substrate; forming an insulating film containing yttria-stabilized zirconia over the gate electrode; forming a microcrystalline semiconductor film on the insulating film containing yttria-stabilized zirconia; forming an amorphous semiconductor film over the microcrystalline semiconductor film; forming a semiconductor film over the amorphous semiconductor film, the semiconductor film including an impurity element; forming an island-like microcrystalline semiconductor film, an island-like amorphous semiconductor film, and an island-like semiconductor film by selective etching of the microcrystalline semiconductor film, the amorphous semiconductor film, and the semiconductor film; forming source and drain electrodes over the island-like semiconductor film; and forming an opening in the island-like semiconductor film and a depressed portion at a top surface of the island-like amorphous semiconductor film after forming the source and drain electrodes, wherein the opening overlaps with the depressed portion, wherein a width of top edges of the depressed portion is smaller than a distance between bottom edges of the source and drain electrodes, and wherein a direction of the width and a direction of the distance are parallel.