Patent ID: 7750476
Filing Date: 2010-07-06
Classification: H01L

Abstract:
1. A semiconductor device having a thin film transistor, the thin film transistor comprising: a semiconductor layer including a source region on an insulating surface; a gate insulating film on and in contact with the semiconductor layer, the gate insulating film defining a contact hole extending from a first opening located at a top surface of the gate insulating film to a second opening located at a bottom surface of the gate insulating film, and the semiconductor layer defining a recess having a third opening located in a top surface of the source region that is in communication with the second opening, the third opening defining an area that is greater than an area defined by the second opening such that a portion of the gate insulating film extends directly over a portion of the recess; a gate electrode on the gate insulating film; and a source electrode in contact with the semiconductor layer through the contact hole, wherein the source electrode contains a first layer and a second layer, wherein the recess is filled with the first layer, wherein the first layer is in contact with the gate insulating film, wherein the first layer is an alloy of aluminum and an element belonging to one of groups 12 to 15, wherein the element belonging to one of groups 12 to 15 is at least one selected from the group consisting of germanium, tin, gallium, zinc, lead, indium, and antimony, and wherein the contact hole is directly over the source region.