To improve the performance of a protection circuit including a diode formed using a semiconductor film. A protection circuit is inserted between two input/output terminals. The protection circuit includes a diode which is formed over an insulating surface and is formed using a semiconductor film. Contact holes for connecting an n-type impurity region and a p-type impurity region of the diode to a first conductive film in the protection circuit are distributed over the entire impurity regions. Further, contact holes for connecting the first conductive film and a second conductive film in the protection circuit are dispersively formed over the semiconductor film. By forming the contact holes in this manner wiring resistance between the diode and a terminal can be reduced and the entire semiconductor film of the diode can be effectively serve as a rectifier element.
申请公布号
US8174047(B2)
申请公布日期
2012.05.08
申请号
US20090495963
申请日期
2009.07.01
申请人
FUKUOKA OSAMU;HAYAKAWA MASAHIKO;SHISHIDO HIDEAKI;SEMICONDUCTOR ENERGY LABORATORY CO., LTD.