Impact ionization rates for strained SiGe

With Fermi's golden rule we have calculated the impact ionization (II) rates for strained SiGe. In our approach, the energy and the momentum are exactly conserved during the calculation of the six-dimensional integral in k-space over 4 conduction and 3 valence bands. The wave-vector space is discretized with a very fine grid with a spacing of up to 1/40 (2pi/a), where a is the lattice constant. II coefficient and quantum yield for relaxed Si and strained SiGe are calculated through Full-Band Monte Carlo simulations. Good agreement between simulation and experimental data for relaxed Si is achieved.