Radiation sensitive thyristor structure with isolated detector

DETAILED DESCRIPTION What is claimed is: 1.
A radiation sensitive semiconductor device comprising: a semiconductor substrate; a radiation sensitive region on said substrate operative to generate an electrical current in response to the incidence of radiation thereon; a gate region responsive to the flow of current therein to turn on said semiconductor device; an isolating region interposed between said radiation sensitive region and said region for increasing the lateral resistance of said substrate layer between said radiation sensitive region and said gate region to a value greater than the lateral resistance of the remainder of said substrate, said isolating region further characterized by a region of locally higher base resistance than the remainder of said substrate surrounding said radiation sensitive region and by a lower impurity concentration than the remainder of said substrate layer; and means for coupling said electrical current from said radiation sensitive region to said gate region for turning on said device in response to the incidence of radiation on said radiation sensitive region.
2.
The radiation sensitive device of claim 1 wherein said region of locally higher base resistance includes a region of relatively thin semiconductor material surrounding said radiation sensitive region compared to the remainder of said semiconductor substrate.
3.
The radiation sensitive device of claim 2 wherein said region of relatively thin semiconductor material comprises an etched down semiconductor region.
4.
The radiation sensitive device of claim 1 wherein said means for coupling current from said radiation sensitive region comprises grid means overlying said radiation sensitive region, and electrode means coupling said grid means to said gate region.




Description:
This invention relates, in general, to semiconductor devices, and more particularly to radiation sensitive semiconductor devices.
Most particularly, this invention is directed to a light triggered thyristor device