New electronic effects in double injection diodes with one deep level

Abstract

Double injection diodes made of high resistivity semiconductors compensated with deep levels show a negative differential resistance region in the stationary I - V characteristic. At lower temperatures the injection level of free carriers can be altered within the prebreakdown region without changing the space charge situation. Therefore (dVdI) = 0 is valid for several orders of magnitude of the current. Furthermore, the switching of the diode from the “off state” (prebreakdown region) to the “on-state” (high injection or semiconductor regime) can be delayed by applying a corresponding voltage V >VBD, the breakdown voltage. An exponential dependence of the delay time tD on the applied voltage is found. The lower limit of tD is determined by the free carrier lifetime, an upper limit does practically not exist if the temperature is low enough.