ELECTRONIC DEVICES COMPRISING THIN-FILM TRANSISTORS

摘要

A large-area electronic device, such as an AMLCD, has switching TFTs (Tp) in a matrix and circuit TFTs (Ts) in a peripheral drive circuit. Both the TFTs (Tp, Ts) comprise a field-relief region (130) which has a lower doping concentration (N-) than their drain region (113) and which is present between their channel region (111) and the drain region (113). This field-relief region (130), at least over most of its length, overlaps with the gate (121) in the circuit TFTs (Ts) so as to reduce series resistance in the field-relief region (130) by conductivity modulation with the gate (121). However, the drain region (113) in the switching TFTs (Tp) is offset from overlap with their gate (121) by at least most of the length of their field-relief region (130). This field-relief offset permits the switching TFTs (Tp) to have a lower leakage current than the circuit TFTs (Ts).