3-D simulation of 5 MeV alpha particles inside Si diodes utilizing a modified delta-ray model

A three-dimensional ionization track is constructed by dividing the range of the ion into cylindrical layers perpendicular to the ion path. At each layer, the ion energy, velocity, effective charge, and maximum energy transfer to atomic electrons of silicon are determined. These parameters are used in a modified semi-analytical δ-rays model to determine the track at each layer equals the maximum range of δ-rays. The 3-D device simulator PADRE is used in the simulation. Current pulses as well as charge collected are compared with experimental measurements for each diode. Agreement between simulation results and experimental measurements are within 8-15% for total charge collected.