The temperature behavior of barrier-controlled silicon-pnp-diodes

The temperature behavior of silicon-pnp-diodes was investigated. The application of the drift-diffusion theory gives an exponential dependence of the diode current on the smallest potential barrier in the diode. The calculation of this potential barrier is limited to diodes which are already in thermal equilibrium far in the punch-through. A model which takes into account the effect of an electron charge was developed to explain the high temperature sensitivity of the electrical characteristics measured on pnp-structures. The electron current balance equation deduced from the continuity equation shows a correlation between the potential barrier and the maximum electron concentration in the base. The hypotheses of the analytical model were checked with a numerical simulation of the diode. The experimental data show good agreement with theory.