Analysis of the Charge Collection Mechanism of the Diamond Based on a Multi-physics Method

Diamond is one of the most important wide-band-gap semiconductors for radiation detection and electronic device upgrading, however, for the lack of effective quantitative simulation method, the generation, recombination and movement of carriers in this material are still far from fully studied. In this paper, a multi-physics method for quantitative analysis of these complicated processes in diamond is established. Furthermore, charge collection process in a diamond detector with incident protons is quantitatively studied by using this method. It can be concluded that the influence of carrier lifetime on charge collection efficiency (CCE) is saturated when the value of carrier lifetime is greater than the characteristic time for carriers to cover the diamond device. The influence of electric field on CCE is saturated when the value of electric field strength is greater than 1 MV/m. By comparison of the simulated results and the theoretical results of an ideal case, good agreements have been acquired in both saturated electric field and unsaturated electric field conditions. All these results indicate that this method is useful for quantitative simulation and further optimization design of diamond detectors and other devices.