Influence of vertical scaling and temperature on impact-ionization effects in SiGe HBTs

The temperature influence on impact-ionization mechanisms in advanced silicon-germanium heterojunction bipolar transistors is analyzed over the temperature range from 300 to 380 K for different technological nodes. Accurate results are obtained by performing simulations through a deterministic solver of the Boltzmann Transport Equation based on the spherical harmonics expansion of the distribution function. In particular, the impact of vertical scaling and lattice temperature on the open-base breakdown voltage BV
CEO
and the BV
CEO
×f
T,PEAK
product is investigated.