THIN FILM TRANSISTOR AND METHOD OF MANUFACTURING THE SAME

摘要

As source and drain wiring, a base layer and a cap layer are each formed of a MoNiNb alloy film, and a low-resistance layer is formed of Cu. The resultant laminated metal film is patterned through one-time wet etching to form a drain electrode and a source electrode. Cu serving as a main wiring layer does not corrode because of being covered with a MoNiNb alloy having good corrosion resistance. Further, even when a protective insulating film including an oxide is formed by plasma CVD in an oxidizing atmosphere, Cu is not oxidized. With the wet etching, the sidewall taper angle of the laminated metal film can be controlled to 20 degrees or more and less than 70 degrees.

主权项

1. A thin film transistor, comprising:
a gate electrode; a gate insulating film; a channel layer containing an oxide semiconductor; a source electrode and a drain electrode; and a protective film, wherein: at least one of the gate electrode, the source electrode, the drain electrode, and any other conductor wiring layer contributing to operation of the thin film transistor is formed of a laminated metal film comprising a lower barrier layer, a low-resistance main wiring layer, and an upper cap layer; the low-resistance main wiring layer contains one of copper and a copper alloy; and at least one of the lower barrier layer and the upper cap layer contains a molybdenum alloy containing nickel and niobium.