| 摘要 |
TFT mfg. process involves: (a) depositing a first doped polysilicon layer on an insulating substrate (10) and etching the layer to form source (16) and drain (18) contacts; (b) forming, on the etched first layer, a transistor channel in an etched second polysilicon layer (20) having edges overlapping the source and drain contacts; (c) depositing a first insulation layer (22), for forming the gate insulation, on the second polysilicon layer; (d) depositing a conductive layer (24), for forming the gate, on the first insulation layer and etching the conductive layer (24) and the first insulation layer (22) to define the gate dimensions, such that the etched edge at the drain side is offset w.r.t. the drain contact (18) and that the gate length is less than the channel length; and (e) depositing a second insulation layer (30) on the polysilicon exposed during step (d). USE/ADVANTAGE - The TFT is esp. used for an active matrix LCD flat screen. It has reduced leakage current and maintained drain current in the conducting state. The process is simple and is compatible with prodn. of large (e.g. 1 sq.m) flat screens.
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