Temperature dependence of hole drift mobility in high-purity single-crystal CVD diamond

Hole transport properties in high-purity single crystal CVD diamond samples were studied using the time of flight technique with optical excitation of the carriers. The measurements were taken at different temperatures in the interval 80-470 K. By varying the intensity of the optical excitation over several orders of magnitude, measurements at different carrier concentrations have been performed. In this way, measurements have been made both in the space charge limited and non space charge limited regimes, with consistent results. The temperature dependence of the low-field hole drift mobility shows a 7(alpha) dependence with a approximate to -1.5, below 350 K. This indicates that acoustic phonon scattering is the dominant scattering mechanism and a very low concentration of ionized impurities in this material. (c) 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.