Electric field ionization of boron acceptors in single-crystalline diamond

Vertical hole transport in single-crystalline diamond films with ohmic and Schottky contacts was studied at dc and pulsed electric fields up to ∼ 5⋅105 V/cm. Conductivity mechanisms at different fields were identified. The concentrations of free carriers (holes) and acceptors were determined. The hole recombination time at boron acceptors has been estimated. The mechanisms of electric field ionization of boron acceptors are discussed.