Effect of deep dislocation levels in silicon on the properties of p-n junctions

Abstract

We present the results of studies on the influence of deep levels, due to dislocations in electronic-grade silicon, on the lifetime of minority carriers and on the current-voltage and capacitance-voltage characteristics of p-n junctions. The parameters of the deep levels were determined by means of dynamic spectroscopy. The carrier lifetime in the high-resistance region of the p-n junction correlates well with the dislocation density and varies from 10−7 sec to 3 · 10−8 sec when the dislocation density Nd varies from 107 cm−2 to 5 · 103 cm−2. The voltage across the p-n junction at a high level of injection varies 1.6 to 6.2 v as a function of Nd. The ionization energy of deep levels associated with dislocation in silicon is 0.44 and 0.57 eV, measured from the bottom of the conduction band.