Hole transport in p-type ZnO

A two-band model involving the A- and B-valence bands was adopted to analyze the temperature-dependent Hall effect measured on p-type ZnO. The hole transport characteristics (mobilities and effective Hall factor) are calculated using the relaxation time approximation as a function of temperature. It is shown that the lattice scattering by the acoustic deformation potential is predominant. In the calculation of the scattering rate for ionized impurity mechanism, an activation energy of 100 or 170 meV is used at different compensation ratios between donor and acceptor concentrations. The theoretical Hall mobility at an acceptor concentration of 7 x 10(18) cm(3) is about 70 cm(2) V-1 s(-1) with the activation energy of 100 meV and the compensation ratio of 0.8 at 300 K. We also found that the compensation ratios conspicuously affected the Hall mobilities.