Температурная зависимость напряжения шнурования тока в мощных ВЧ и СВЧ биполярных транзисторах

Abstract

The results of studies of the temperature dependence of the voltage UKL of current lacing in power RF and microwave bipolar transistors (PBT) in the temperature range from - 60 to 90 ° C on the upgraded unit UITEP-M for measuring the thermoelectric parameters of high-power transistors are presented. The principle of operation of the installation is based on measuring the amplitude of the variable component of the voltage at the emitter junction of the PBT when a constant emitter current is passed and the sum of linearly increasing and small alternating voltage is applied to the collector; current lacing in the transistor structure manifests itself in a sharp increase in the steepness of the dependence. On a sample of PBT type KT903A, it was experimentally established that with an increase in the temperature of the housing, the current lacing voltage decreases noticeably and at a certain temperature, the TCR reaches a minimum value of UKLmin, and then increases again with an increase in the temperature of the housing. It is shown that the greater the thermal resistance of the transistor junction-housing in the diode connection, the weaker the temperature dependence of the lacing voltage. The obtained results are qualitatively explained on the basis of a one-dimensional model.