| 摘要 |
PURPOSE:To make the speed of a function as a transistor high, by making a carrier mobility in a region, in which the step part of a semiconductor thin film is formed, higher than the other region, and forming a channel forming region including said region. CONSTITUTION:A polycrystalline semiconductor thin film 2 is locally formed on a substrate 1. A gate electrode 4 is formed on the thin film 2 through a gate insulating film 3. A source electrode 5 and a drain electrode 6 are formed at two positions of the thin film 2. A relatively thick insulating layer 31 is locally formed on the substrate 1. The thin film 2 is extended on the insulating layer 31 continuously on the substrate 1 by way of a side surface 32 of the layer 31 so as to form a step part. A channel region is constituted so that the number of grain boundaries is much fewer in comparison with the other region. The channel region includes a region wherein the step part of the thin film 2 is included. |
