Active matrix display device

摘要

A wiring formed on a substrate is oxidized and the oxide is used as a mask for forming source and drain impurity regions of a transistor, or as a material for insulating wirings from each other, or as a dielectric of a capacitor. The thickness of the oxide is determined depending on the purpose of the oxide. In a transistor adapted to be used in an active-matrix liquid-crystal display, the channel length, the distance between the source region and the drain region, is made larger than the length of the gate electrode taken in the longitudinal direction of the channel. Offset regions are formed in the channel region on the sides of the source and drain regions. No or very weak electric fields are applied to these offset regions from the gate electrode.