Electron Beam Amplification Using Thin Diamond

DIAMOND HAS A NEGATIVE EELCTRON AFFINITY ON ITS (111) FACE AND P-TYPE DIAMOND IS CONDUCTIVE. UNFORTUNATELY, DOPING OF DIAMOND TO MAKE IT CONDUCTIVE DECREASES THE CARRIER MOBILITIES WHILE INCREASING THE TRAP DENSITIES. EXPERIMENTS WITH P-TYPE DIAMOND HAVE NOT YET PRODUCED SIGNIFICANT CURRENTS. IN THE PROPOSED STUDY AN ENTIRELY NEW APPROACH IS INVESTIGATED. YTHIN WAFERS OF NATURAL TYPE IIa DIAMOND ARE MADE CONDUCTIVE VIA ELECTRON BOMBARDMENT. CARRIER PAIRS ARE PRODUCED IN THE DIAMOND AT THE RATE OF ONE PAIR PER 16.5 eV OF BOMBARDING ELECTRON ENERGY. THE GENERATED CARRIER PAIRS ARE AVAILABLE TO BE DRAWN OUT INTO THE VACUUM BEFORE THEY BECOME TRAPPED OR RECOMBINE. FOR A BOMBARDING ENERGY OF 30 keV FOR INSTANT, A CURRENT GAIN OF 1800 COULD BE REALIZED. THE SCHEME IS THUS ONE OF CURRENT AMPLIFICATION. THE EXCITING ELECTRON BEAM COULD COME FROM A FIELD EMITTER ARRAY, LEADING TO AN ALL SOLID STATE COLD ELECTRON SOURCE WITH HIGH CURRENT DENSITY AND HIGH CURRENT OUTPUT.