EXTRINSIC PHOTOCONDUCTIVITY SWITCHES USING CVD DIAMOND

EXTRINSIC PHOTOCONDUCTIVITY SEMICONDUCTOR SWITCHES (PCSS) BASED ON CVD DIAMOND-FILM (DF) HAS BEEN DEVELOPED. DIAMOND MATERIAL POSSESSES SEVERAL ADVANTAGES SUCH AS HIGH THERMAL CONDUCTIVITY AND HIGH BREAKDOWN VOLTAGES. THE PCSS BASED ON CVD DIAMOND CAN BE SUPERIOR THAN ITS COUNTERPARTS (GAAS OR SI) BY EXPLOITING THESE ADVANTAGES. CONVENTIONAL PCSS'S BASED ON GAAS SUFFER FROM PROBLEMS SUCH AS THERMAL RUNAWAY; WHILE THAT SAME DEVICES BASED ON SILICON ENCOUNTER THE DIFFICULTIES SUCH AS SPEED LIMITATION. IN GREATE CONTRAST, DIAMOND-BASED PCSS'S ARE FREE FROM THESE SHORTCOMINGS. THE ONLY PROBLEM THAT DIAMOND PCSS MAY ENCOUNTER IS THE LACKING OF SUITABLE LIGHT SOURCES FOR ITS INTRINSIC TYPE PHOTOEXCITATION. SHORT-WAVELENGTH LIGHT PULSES ARE REQUIERED IN CARRIER EXCITATIONS OF THE 5.5 ELECTRON VOLTS (EV) ENERGY BANDGAP FOR INTRINSIC DIAMOND. THE DEVELOPMENT OF THE EXTRINSIC DIAMOND PCSS'S, WHICH OPERATE IN THE VISIBLE SPECTRUM, HAS GREATLY SIMPLIFIED THIS PROBLEM AND PROVIDED FOR PHOTOCONDUCTIVITY APPLICATIONS IN THE IR TO VISIBLE RANGE.