EXPERIMENTAL RESEARCH AND COMPUTER SIMULATION OF MULTI-CASCADE COMPOSITE TRANSISTORS FOR STABILIZING THE OPERATING MODE OF OUTPUT CASCADES OF RADIO ENGINEERING DEVICES

Experimental results and computer simulation of multi-stage composite transistors are presented. To study the volt - ampere characteristics of multistage composite transistors, a dialogue computer simulation program, the Delphi programming environment, has been developed. It is shown that the proposed multistage composite transistors can improve manufacturability in its industrial production. It is shown that multistage homostructure transistors according to the Darlington and Shiklai circuits operate stably at collector-emitter voltages five times higher than in the case of individual transistors. The power dissipated on the collector is 3 times higher than the rated value of the maximum permissible power of the composite transistors. It is established that the efficiency of the method of stabilizing the emitter current of a three-link homostructure transistor is 7 times higher in voltage and three orders of magnitude higher in temperature compared to a conventional composite transistor. The proposed homostructure transistors are designed to operate in terminal stages of power amplifiers, radio transmitting devices, electronic equipment of industrial and automotive electronics

Effects of Electrical Stress and High-Energy Electron Irradiation on the InGaP/GaAs Heterojunction Phototransistor

ABSTRACTIn this paper, we discuss the characteristics of the InGaP/GaAs heterojunction phototransistors (HPTs) before and after the electrical stress at room temperature and assess the effectiveness of the emitter-ledge passivation. Although an electrical stress given to the phototransistors by keeping a collector current density of 37 A/cm2 for 1 hour at room temperature was too small to affect the room-temperature common-emitter current gain and photocurrent of both HPTs with and without the emitter-ledge passivation, they showed a significant decrease at 420 K due to the room-temperature electrical stress. Nevertheless, the room-temperature common-emitter current gain and photocurrent of the HPT with the emitter-ledge passivation were still higher than those of the HPT without the emitter-ledge passivation. The effectiveness of the emitter-ledge passivation against the electrical stress was more significant than that on the current gain in the dark. In addition to the electrical stress experiment, for a potential application of the InGaP/GaAs HPTs in space, we will irradiate the HPTs with 1-MeV electrons at the Japan Atomic Energy Agency. Both current gain and photocurrent decreased significantly after the electron irradiation. In contrast to the electrical stress, the damage due to the high-energy electron irradiation is a bulk-related phenomenon, and the emitter-ledge passivation does not seem to suppress the degradation.