Charge transport in high mobility single crystal diamond

摘要

Time of Flight (TOF) measurements using conventional laser TOF and alpha-partide TOF setups have been carried out on high quality CVD diamond samples to study the electron and drift mobility and to compare them with the mobility data for HA diamond. The measured mobilities for all samples investigated are in the range 2000-2250 cm~2/Vs for holes and 2200-2750 cm~2/Vs for electrons, thus close to the theoretical prediction as well as to Ha diamond mobility values. The charge transient profile measured in the laser TOF measurements is influenced by the electric field profile in the sample, which might be changed based on the charge trapping at low electric fields applied, depending on the surface atomic termination. The temperature dependence of the drift mobility indicates that at room temperature the scattering on acoustic phonons is the main dominant scattering mechanism and the contribution of other types of carrier scattering mechanism is negligible.