Patent ID: 9046482
Filing Date: 2015-06-02
Classification: G01N,H01L

Abstract:
1. A method for manufacturing a gas sensor having a detection portion and a circuit portion, the method comprising the steps of: forming a first gate electrode layer and a second gate electrode layer over an insulating surface; forming a gate insulating layer over the first gate electrode layer and the second gate electrode layer; forming a first oxide semiconductor layer and a second oxide semiconductor layer over the gate insulating layer; and forming a protective insulating layer comprising an oxide insulating film and a silicon nitride film over the second oxide semiconductor layer, the oxide insulating film being in contact with an exposed portion of the second oxide semiconductor layer, wherein the first gate electrode layer and the first oxide semiconductor layer are formed in the detection portion, and wherein the second gate electrode layer, the second oxide semiconductor layer, and the protective insulating layer are formed in the circuit portion.