Optically Induced Series Resistance and Microwave Properties of n+ np+ GaAs and Si IMPATT Diode

The effect of laser radiation on the n⁺ side of the n⁺np⁺ semiconductor junction structure of GaAs and Si IMPATT diode at X band has been studied. Following Gummel-Blue approach (1967) and considering the experimental ionization parameters of GaAs (Groves et al., 2003) and Si (Grant, 1973), the present study predicts that the enhancement of optically induced leakage current increases the value of crucial series resistance with an overall degradation in the microwave negative resistance properties, but with an advantage of wider tuning range at 22 C of the diode. It is also observed that GaAs diode yields lower values of series resistance and higher values of negative conductance than its Si IMPATT counterpart at X band.