| 摘要 |
<p>PURPOSE:To obtain an inexpensive active matrix substrate which uses thin film transistors having sufficiently large ON current, a sufficiently small OFF current and excellent reproducibility and reliability by employing a true polycrystalline silicon thin film on a channel region and a true polycrystalline silicon thermally oxidized film on a gate insulated film. CONSTITUTION:After a true polycrystalline silicon 9 is accumulated on an insulating substrate 8, a thermal oxidation is performed, thereby forming a gate insulated film 12. Then, a gate electrode 13 and a common electrode 17 of a condenser are formed. These two electrodes may be formed of the same conductive material simultaneously. Subsequently, after an impurity is doped to form source and drain regions 10, 11, an interlayer insulated film 14 is accumulated, and a contacting hole is opened. The doping of the impurity to the source and drain regions is performed by thermal diffusion or ion implantation. Subsequently, a gate line 15 is formed, and a drive electrode 16 is then formed to complete it. In this manner, the true polycrystalline silicon thin film is used to increase the ON current in the channel region, and the OFF current is reduced. Further, the impurity is not doped in a true shape, thereby minimizing the OFF current.</p> |
