Waveguide switch with semiconductor in thermal contact with waveguide walls

Claim 1

A MICROWAVE DEVICE COMPRISING A SECITON OF WAVEGUIDE, A SEMICONDUCTOR JUNCTION ELEMENT, SAID ELEMENT COMPRISING A BODY OF HIGH RESISTIVITY SEMICONDUCTOR MATERIAL OF ONE CONDUCTIVITY TYPE HAVING A PAIR OF SURFACE REGIONS EACH INCLUDING ONE OF RESPECTIVE OPPOSITE FACES OF THE BODY, SAID REGIONS BEING OF HIGH ELECTROCAL CONDUCTIVITY OF P AND N CONDUCTIVITY TYPE RESPECTIVELY WITH A PN JUNCTION BETWEEN SAID HIGH RESISTIVITY MATERIAL AND THE SURFACE REGION OF OPPOSITE CONDUCTIVITY TYPE AND WITH EACH OF SAID FACES COVERED BY A LAYER OF ELECTRICALLY CONDUCTIVE MATERIAL WHICH SERVES AS A CONTACT TO THE ELEMENT, WITH THE ELEMENT MOUNTED IN THE SECTION OF WAVEGUIDE WITH ONE FACE OF THE ELEMENT IN THERMAL CONTACT WITH A WALL OF SAID WAVEGUIDE, AND MEANS FOR APPLYING BIAS VOLTAGES OF SUITABLE POLARITY AND MAGNITUDE BETWEEN SAID CONTACTS TO CONTROL THE IMPEDANCE OF THE ELEMENT TO REQUIRED VALUES BETWEEN TWO EXTREME CONDITIONS IN WHICH THE ELEMENT IS HIGHLY CONDUCTIVE AND HIGHLY RESISTIVE RESPECTIVELY, SUCH THAT DURING THE OPERATION OF THE DEVICE IN THE FIRST EXTREME CONDITION OF THE ELEMENT THE PENETRATION OF MICROWAVE ENERGY IS SUBSTANTIALLY CONFINED TO A MINOR PROPORTION OF THE ELEMENT AND THE MAJOR PROPORTION THEREOF CONSTITUTES A THERMALLY CONDUCTIVE PATH TO THE WALL OF THE WAVEGUIDE FOR HEAT PRODUCED BY MICROWAVE ENERGY DISSIPATED IN THE MINOR PROPORTION OF THE ELEMENT, AND IN THE SECON EXTREME CONDITION A PROPORTION OF THE ELEMENT IS SUBSTANTIALLY DEPLETED OF CURRENT CARRIES SO THAT THE MICROWAVE ENERGY PASSES THERETHROUGH WITH SUBSTANTIALLY NEGLIGIBLE ABSORPTION.