| 摘要 |
<p>PURPOSE: To obtain a low leakage current characteristic required for pixel elements and a high mobility characteristic required for peripheral drive circuits, by forming crystalline silicon TFTs capable of high-speed operation and amorphous silicon TFTs having a low OFF-current characteristic on the same substrate. CONSTITUTION: Selective crystalization of an amorphous silicon film 12 is performed by applying a laser beam to the region where an extremely thin silicon film 13 containing nickel has been formed of the amorphous silicon film 12. Metal elements of a density of 1×10<16> -5μ10<19> cm<-3> are added to the active region of a thin-film transistor to help the crystalization of silicon. On the occasion of this crystalization a large number of monodomain regions 121 and 122 are formed. Since any metal elements are not introduced into an amorphous region 123, and a laser beam is not applied either, it is not crystalized, and remains in an amorphous state. Accordingly, it becomes possible to form crystalline silicon TFTs capable of high-speed operation and amorphous silicon TFTs having a low OFF-current characteristic on the same substrate.</p> |
