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.