Patent ID: 8441016
Filing Date: 2013-05-14
Classification: G02F,H01L

Abstract:
1. A thin film transistor comprising: a gate electrode formed on a substrate; an insulating layer formed so as to cover the gate electrode; a semiconductor layer that has a channel region made of a polycrystalline semiconductor or a microcrystalline semiconductor and that is formed on the insulating layer; a source contact layer and a drain contact layer that are made of a semiconductor including impurities and that are formed on the insulating layer so as to contact the semiconductor layer; a first source metal layer formed on the source contact layer; a first drain metal layer formed on the drain contact layer; a second source metal layer formed on the first source metal layer; and a second drain metal layer formed on the first drain metal layer, wherein an end portion of the second source metal layer on a side of the channel region is located at a position that is receded from an end portion of the first source metal layer on the side of the channel region, wherein an end portion of the second drain metal layer on a side of the channel region is located at a position that is receded from an end portion of the first drain metal layer on the side of the channel region, wherein the semiconductor layer contains low concentration impurity diffusion regions respectively formed adjacent to the end portions of the source contact layer and the drain contact layer on the side of the channel region, and wherein an impurity concentration of the low concentration impurity diffusion regions is lower than an impurity concentration of the source contact layer and the drain contact layer.