THEORETICAL PREDICTION OF THE IMPACT OF AUGER RECOMBINATION ON CHARGE COLLECTION FROM AN ION TRACK

The theoretical analysis presented here concludes that Auger recombination can reduce charge collection from very dense ion tracks in silicon devices. It is of marginal importance for tracks produced by 270 MeV krypton, and therefore, it is of major importance for ions exhibiting a significantly larger loss. The analysis shows that recombination loss is profoundly affected by track diffusion. As the track diffuses, the density and recombination rate decrease so fast that the linear density (number of electron-hole pairs per unit length) approaches a nonzero limiting value as t --> infinity. Furthermore, the linear density is very nearly equal to this limiting value in a few picoseconds or less. When Auger recombination accompanies charge transport processes that have much longer time scales, it can be simulated by assigning a reduced linear energy transfer to the ion.