THE USE OF REALISTIC BAND-STRUCTURE IN IMPACT IONIZATION CALCULATIONSFOR WIDE BANDGAP SEMICONDUCTORS - THRESHOLDS AND ANTI-THRESHOLDS IN INDIUM-PHOSPHIDE

An accurate pseudopotential model of the band structure of InP is inco rporated into a calculation of band-to-band impact ionizatlon. Because of the relatively large bandgap of InP, the energetic carriers that i nitiate impact ionization have wavevectors whose magnitudes are typica lly a significant fraction of the Brillouin zone (BZ) width. The band structure is accurate throughout the Bz and so allows the threshold an d anti-threshold wavevectors to be reliably calculated for any directi on in wavevector space. Results are given for a range of transitions p ossible at room temperature, and the transitions are categorized accor ding to several criteria. An effective technique for determining the B loch function overlap is also presented, and will be incorporated in r ate calculations in the future.