NONISOTHERMAL ANALYSIS OF BREAKDOWN IN SOI TRANSISTORS

Non-isothermal device simulation is used to calculate the drain characteristics of an SOI transistor. The breakdown voltage is found to be lower when lattice heating is accounted for, rather than higher, as the temperature dependence of the ionization coefficients would suggest. The results of numerical experiments show that this anomalous behavior is due to the temperature dependence of carrier injection caused by parasitic bipolar action. The lattice temperature in the source region thus has a major influence on breakdown behavior.