High voltage, high frequency double diffused metal oxide semiconductor device

Claim 1

IN A HIGH VOLTAGE, HIGH FREQUENCY METAL INSULATOR SEMICONDUCTOR DEVICE, A SEMICONDUCTOR BODY HAVING A CONDUCTIVITY OF ONE TYPE AND FORMING A SUBSTANTIALLY UNIFORM LIGHTLY DOPED DRAIN REGION, SAIID SEMICONDUCTOR BODY HAVING A SUBSTANTIALLY PLANAR SURFACE, A HEAVILY DOPED DRAIN CONTACT REGION FORMED IN THE DRAIN REGION AND EXTENDING TO SAID SURFACE A LAYER OF INSULATING MATERIAL FORMED ON SAID SURFACE, A CHANNEL REGION FORMED IN THE SEMICONDUCTOR BODY HAVING A CONDUCTIVITY OPPOSITE THAT OF THE SEMICONDUCTOR BODY TO FORM A FIRST P-N JUNCTION EXTENDING TO THE SURFACE BENEATH SAID LAYER OF INSULATING MATERIAL, A SOURCE REGION FORMED WITHIN THE CHANNEL REGION OF THE FIRST NAMED CONDUCTIVITY TYPE AND FORMING A SECOND P-N JUNCTION EXTENDING TO SAID SURFACE BENEATH SAID LAYER OF INSULATING MATERIAL, SAID FIRST AND SECOND P-N JUNCTIONS EXTENDING TO SAID SURFACE BENEATH SAID LAYER OF INSULATING MATERIAL, SAID FIRST AND SECOND P-N JUNCTIONS DEFINING A CHANNEL OF PRECISE LENGTH, METALLIZATION FORMING GATE, SOURCE AND DRAIN CONTACTS, SAID METALLIZATION OVERLYING SAID LAYER OF INSULATING MATERIAL AND MAKING CONTACT THROUGH THE INSULATING LAYER IWTH THE DRAIN CONTACT AND SOURCE REGIONS, SAID METALLIZATION OVERLYING THE CHANNEL AND BEING SEPARATED FROM THE CHANNEL BY SAID LAYER OF INSULATING MATERIAL TO FORM THE GATE CONTACT, AND ADDITIONAL METALLIZATION FORMED ON SAID LAYER OF INSULATING MATERIAL AND EXTENDING BETWEEN THE METALLIZATION WHICH PROVIDE SAID GATE AND DRAIN CONTACTS AND IN SUCH A MANNER SO THAT THE ADDITIONA METALLIZATION IS DISPOSED UNSYMMETRICALLY WITH RESPECT TO THE CHANNEL, SAID ADDITIONAL METALLIZATION EXTENDINNG OVER A DRIFT REGION FORMED IN THE UNIFORMLY LIGHTLY DOPED REGION BETWEEN THE CHANNEL AND THE HEAVILY DOPED CONTACT REGION.