THIN FILM SEMICONDUCTOR DEVICE AND METHOD FOR FABRICATING THE SAME

摘要

A thin film semiconductor device employing a substrate produced through such a process as a layer implanted with oxygen ions is formed in a specified area within a non-single crystal semiconductor thin film layer formed on an insulating material basic layer and that layer is converted into an oxide film layer by energy beam irradiation for crystallizing or recrystallizing the non-single crystal semiconductor thin film layer, wherein the oxide film layer is used as the insulation film of a gate electrode. As compared with a prior art thin film semiconductor device employing an oxide film deposited at low temperature by plasma CVD as a gate insulation film, variation in the working threshold value is suppressed significantly and operational stability is enhanced greatly. When irradiation of energy is effected in a specified mode, a thin film semiconductor device having a high mobility in which unit electric circuits are arranged regularly in accordance with the arrangement of semiconductor crystal grains is obtained.