| 摘要 |
<p>PURPOSE: To increase OFF resistance for improving the voltage holding rate in a pixel part and to decrease ON resistance for increasing the mobility in a driving circuit part by controlling the size or density of a low-density region in an LDD structure. CONSTITUTION: Source and drain regions 11S, 11D are formed which are self- aligned to a gate electrode 13 by injecting ions of n-type impurities in a channel layer 11. Respective region 11S, 11D are divided into a high density region n<+> and a low density region n<-> by injecting ions twice in such a manner that the low density region n<-> in a pixel part has width L1 larger than the width L2 of the low density region n<-> in a driving circuit part. By this method, the resistance in the channel layer 12 in the pixel part is increased and in the driving circuit part, the resistance is decreased. Thus, OFF resistance is increased in the pixel part to improve the holding rate of voltage applied on a liquid crystal, while in the driving circuit, ON resistance is decreased to improve the mobility.</p> |
