Semiconductor tetrode

Claim 1

A SEMICONDUCTOR DEVICE COMPRISING A BODY OF SEMICONDUCTOR HAVING: A FIRST REGION OF ONE CONDUCTIVITY TYPE, A SECOND REGION OF THE OPPOSITE CONDUCTIVITY TYPE DISPOSED WITHIN SAID FIRST REGION, EXTENDING INWARDLY FROM ONE OF THE SURFACES OF SAID FIRST REGION AND FORMING A FIRST PN JUNCTION WITH SAID FIRST REGION HAVING AN EDGE AT THE SURFACE OF SAID BODY OF SEMICONDUCTOR, A THIRD REGION FORMING A SECOND PN JUNCTION WITH THE OPPOSITE SURFACE OF SAID FIRST REGION, SAID SECOND PN JUNCTION ALSO HAVING AN EDGE AT SAID SURFACE OF SAID BODY OF SEMICONDUCTOR, AN ALIGNMENT OF SPACED-APART REGIONS OF SAID OPPOSITE CONDUCTIVITY TYPE DISPOSED WITHIN SAID FIRST REGION EXTENDING INWARDLY FROM ITS SURFACE AND FORMING AN ALIGNMENT OF PN JUNCTIONS THEREWITH WHICH HAVE EDGES AT SAID SURFACE OF SAID BODY OF SEMICONDUCTOR, SAID EDGES ALL LYING BETWEEN SAID EDGES OF SAID FIRST AND SECOND PN JUNCTIONS, A SURFACE CHANNEL REGION ADJACENT TO SAID FIRST REGION AND EXTENDING BETWEEN SAID FIRST PN JUNCTION AND SAID ALIGNMENT OF PN JUNCTIONS, A CONTROL ELECTRODE CAPACITATIVELY COUPLED TO THE SEMICONDUCTOR IN SPACED RELATIONSHIP TO SAID SURFACE CHANNEL REGION AND THE EDGES OF SAID FIRST PN JUNCTION AND SAID ALIGNMENT OF PN JUNCTIONS, SAID ELECTRODE ADAPTED TO CHANGE THE CONDUCTIVITY TYPE OF SAID SURFACE CHANNEL IN RESPONSE TO A CHANGE IN THE POTENTIAL AT SAID ELECTRODE, AND MEANS FOR PASSING ELECTRIC CURRENT ACROSS SAID FIRST AND SAID SECOND PN JUNCTIONS.