Concerning the nature of relaxation oscillations in silicon diodes in the cryogenic temperature region

Time-resolved measurements have been performed of periodic oscillations in the voltage drop across a silicon diode which is fed by stabilized direct current (the situation for temperature measurement) in the region of instability connected with low-temperature impurity breakdown. Analysis of this effect was made on the base of simultaneous consideration of current–voltage characteristics of the diode under the same conditions. From these characteristics, by means of a new analytical method, the voltage-dependent series resistance, the breakdown voltage of the diode base, and equivalent diode capacity responsible for the observed oscillations have been determined. For the first time, practically linear relation between the feeding current and the oscillations frequency has been explained. This relation follows from the fact of approximate constancy of the charge accumulated by the equivalent diode capacity before the breakdown (irrespective of the feeding current value).