Properties of avalanche injection and its application to fast pulse generation and switching

The positive- and negative-resistance characteristics of the avalanche-injection diode are derived from a set of fundamental equations. The field dependence of the ionization rate-constant, the resistivity of the avalanching region, and the injected current are taken into account to compute the final voltage-current characteristics. From these characteristics, the transient electrical time constant for switching is estimated. The discussions of the injection-stimulated avalanche are extended to a transistor for pulse generation at a high repetition rate. Sharp pulses as fast as 500 MHz have been observed with this "injection-controlled avalanche thyristor." The device is suitable for pulse amplification. Also realized are negative resistances in both emitter and collector characteristics, which also operate very rapidly. Discussions are speculatively extended to the possibility of a repetition rate as high as 1000 MHz.