| 摘要 |
<p>PURPOSE:To reduce the areal ratio to be occupied by a circumferential driving circuit to nearly half without deteriorating the characteristic by a method wherein a single gate thin film transistos is provided in a liquid crystal driving element, and a double gate thin film transistor is provided in the circumferential driving circuit. CONSTITUTION:The numerals shown in the figure indicate respectively a first gate electrode 25, a first insulating film 26, a semiconductor thin film 27, a source region 28, a drain region 29, a second gate insulating fim 30, a second gate electrode 31, an interlayer insulating film 32, a source electrode 33, and a drain electrode 34. At the double gate thin film transistor like this, an OFF current and an ON current can be increased together as compared with the single gate thin film transistor. That is because channels to be formed by exciting carriers are formed on both the sides of an upper and a lower layers of the semiconductor thin film, and in short, the ON current and the OFF current together can be obtained at the values of nearly 2 times of the single gate thin film transistor. The characteristic of nearly the same as usual can be obtained with transistor size of half, and the area occupied by the circumferential driving circuit can be reduced to nearly half as compared with the conventional device.</p> |
