abstract |
By reducing the number of exposure masks, one of the problems is to simplify the photolithography process and to produce a semiconductor device having an oxide semiconductor at low cost and with good productivity. A method of fabricating a semiconductor device having an inverted staggered thin film transistor having a channel etch structure, wherein the oxide semiconductor film and the conductive film are etched using a mask layer formed by a multi-gradation mask that is an exposure mask in which transmitted light has a plurality of intensities. The process is performed. The etching process uses dry etching by etching gas. [Index] Oxide Semiconductors, Channel Etching, Multi-Grade Masks, Dry Etching, Bottom Gates |