Patent ID: 6011275
Filing Date: 2000-01-04
Classification: G02F,H01L

Abstract:
A semiconductor device comprising a semiconductor circuit being formed over a substrate having an insulating surface,said semiconductor circuit including:a metal element added region having a longitudinal shape and being introduced with a metal element being capable of promoting crystallization of silicon,at least a thin film transistor formed on the insulating surface, said thin film transistor comprising:an active layer comprising crystalline silicon and being formed in a region where crystal grows in parallel to the insulating surface from the metal element added region,a source region, a drain region, and a channel forming region formed between the source and drain regions, anda gate electrode formed adjacent to at least the channel region with a gate insulating film therebetween, andat least a wiring being connected to the thin film transistor,wherein a longitudinal direction of the metal element added region is substantially identical with a direction of moving carriers in the active layer,wherein the metal element added region extends longer over an end portion of the active layer, andwherein at least a portion of the metal element added region is overlapped with the wiring and said portion of the metal element added region extends in parallel with an overlapped portion of the wiring,wherein the thin film transistor is an n-channel thin film transistor or a p-channel thin film transistor and wherein said n-channel thin film transistor has a S value not higher than 90 mV/dec while said p-channel thin film transistor has a S value not higher than 100 mV/dec.