Models of formation and erosion of a plasma column in a silicon surface-barrier detector

Abstract

Quantitative models of the formation and erosion of the plasma column are presented. With the model of formation, the radius, volume, and surface area of the plasma column and the number and the density of the electron-hole pairs are calculated. In the model of the erosion, the change of the dielectric quality of the plasma column due to the enlargement of its volume is considered to be the cause of the erosion. The internal electric field strength of the plasma column is determined as a function of time. With this model, plasma delays are estimated for alpha particle, 40Ar and 129Xe ions and are compared with other author’s experiments. Ideally the recombination effect should be calculated as a product of the recombination rate and the time interval of the plasma delay. However, it is estimated here using two parameters for the fission fragments from thermal-neutron-induced fission of 235U because of the lack of adequate experimental data.