Reverse epitaxial transistor

Claim 1

A REVERSE EPITAXIAL TRANSISTOR HAVING A SUBSTRATE, A FIRST REGION, A SECOND REGION, AND A THIRD REGION, WHICH COMPRISES: A SUBSTRATE OF ONE CONDUCTIVITY TYPE, AN EPITAXIAL LAYER ON SAID SUBSTRATE, A FIRST REGION OF SAID ONE CONDUCTIVITY TYPE DISPOSED AT LEAST IN PART WITHIN SAID SUBSTRATE, A SECOND REGION OF THE OPPOSITE CONDUCTIVEY TYPE FROM SAID SUBSTRATE DISPOSED WITHIN SAID EPITAXIAL LAYER AND ADJACENT TO SAID FIRST REGION, FORMING A FIRST PN JUNCTION THEREWITH, THE CHARGE CARRIER CONCENTRATION IN THE AREA OF SAID FIRST REGION WITHIN ABOUT ONE DIFFUSION LENGTH BENEATH SAID FIRST PN JUNCTION BEING SUBSTANTIALLY IN EXCESS OF THE AVERAGE CHARGE CARRIER CONCENTRATION IN THE PORTION OF SAID SECOND REGION BENEATH SAID THIRD REGION, AND A THIRD REGION OF SAID ONE CONDUCTIVITY TYPE DISPOSED WITHIN AND IMMEDIATELY ADJACENT OF SAID SECOND REGION, FORMING A SECOND PN JUNCTIION THEREWITH SAID SECOND PN JUNCTION COMPLETELY SURROUNDING AND ISOLATING SAID THIRD REGION.