CV and DLTS Experiments in Boron-Doped Diamond

Abstract

Capacitance–voltage (CV) and deep level transient spectroscopy (DLTS) experiments are applied to explore various properties of boron-doped type IIb high-pressure high-temperature diamond and of homoepitaxially grown boron-doped CVD diamond: contact properties of Al contacts, acceptor density determination, energy distributions and densities of compensating defects and the interaction of boron acceptors with atomic hydrogen (deuterium). Two distinct excitation energies at 0.9 and 1.25 eV are detected by DLTS and optically excited DLTS. We propose a defect/acceptor model where holes are optically excited from defects 1.25 eV above the valence band edge either into ionized boron acceptors at 0.36 eV above EV (optical excitation ≈0.9 eV) or directly into the valence band (photon energy ≥1.25 eV). We also discuss the decrease of the capacitance after deuteration as detected by CV measurements based on deuterium–boron complex formation.