MANUFACTURE OF AMOLPHOUS SILICON THIN FILM TRANSISTOR

摘要

PURPOSE:To completely eliminate increase of off-current caused by current paths, by realizing an amolphous silicon layer of P-type on the rear side and by preventing formation of electric paths at an interface of the amorphous silicon layer and a protective insulating layer. CONSTITUTION:The rear side 4a which is not opposite to a gate electrode 2 of an amolphous silicon layer 4 is exposed to vapor phase atmosphere 14 which is provided with gas containing impurity which becomes acceptor. The impurity is activated by electric field or photo energy and doped to an amolphous silicon layer 4 from the rear 4a of the amolphous silicon layer 4. The amolphous silicon layer of the rear side 4a thereby becomes P-type and electric path formed in an interface of the amolphous silicon layer 4 and a protective insulating layer 3 is not formed without applying some amount of positive voltage to a shield layer. In this way, increase of off-current caused by current flowing through current path formed in an interface can be eliminated.