Radiation induced diode structure

A method of forming a semiconductor device, comprising the steps:

• providing a substrate comprising semiconductor material;
• forming a dielectric layer over said substrate;
• forming a p-type intrinsic base region of an NPN bipolar junction transistor in said substrate;
• forming an n-type emitter in said substrate abutting said p-type intrinsic base region, said n-type emitter extending up to said dielectric layer;
• implanting p-type dopants into said substrate to form a p-type extrinsic base region in said substrate abutting said p-type intrinsic base region, said p-type extrinsic base region extending up to said dielectric layer, said p-type extrinsic base regions being laterally separated from said n-type emitter, and said p-type intrinsic base region extending up to said dielectric layer between said n-type emitter and said p-type extrinsic base region, said dielectric layer being at least 50 nanometers thick over said p-type intrinsic base region between said n-type emitter and said p-type extrinsic base region;
• and
• implanting p-type dopants into said substrate top form a p-type RIDS region in said substrate, said p-type RIDS region extending up to said dielectric layer between said n-type emitter and said p-type extrinsic base region, said p-type RIDS region being laterally separated from said p-type extrinsic base region and from said n-type emitter, said p-type RIDS region having an average doping density greater than 5 times and average doping density of said p-type intrinsic base region.