Holes in boron-doped diamond: comparison between experiment and an improved model

A model for the calculation of the hole concentration in boron-doped diamon d is presented. It is based on details of the structure of the valence band and on careful energy balance around the valence band edge. The effect of a variable hole effective mass is first examined. It is found that both the hole concentration and its activation energy increase with increasing hole effective mass. The calculations are then compared with selected available experimental data. Close agreement between experiment and calculation is r eached. It is concluded that the model correctly describes the thermal gene ration of holes from the acceptor levels to the valence band. Finally, the difficulty of determining the acceptor and donor concentrations independent ly of the hole effective mass is discussed. (C) 2000 Elsevier Science S.A. All rights reserved.