Patent ID: 8513661

Claim:
A thin film transistor comprising: a substrate; a first gate electrode formed on said substrate; a first gate insulating layer formed so as to cover said first gate electrode; a semiconductor layer comprising an oxide semiconductor and formed on said first gate insulating layer; a second gate insulating layer formed on said semiconductor layer; a second gate electrode formed on said second gate insulating layer; and a drain electrode and a source electrode formed so as to be connected to said semiconductor layer, wherein said second gate electrode has a thickness larger than a thickness of said first gate electrode, and wherein a thickness of said first gate electrode is equal to or smaller than a thickness of said first gate insulating layer, and wherein said first gate electrode, said first gate insulating layer, said second gate insulating layer, said semiconductor layer, said drain electrode, and said source electrode have a transmittance of 50% or more for light having a wavelength of 365 nm or more.