Hydrogen-terminated diamond is a promising platform for diamond-based high-power-frequency electronics and radiation-hardened semiconductor devices exhibiting controllable electrical conduction through an accumulated sub-surface 2D hole-gas layer. The diamond conductivity is highly sensitive to local surface conditions, offering new opportunities for device engineering, quantum sensors, and switches, as well as presenting a challenge for device stability. Here we study the impact of focused electron-beam exposure on hydrogen-terminated transfer-doped diamond, revealing a reversible loss of local conductivity. Using Kelvin probe force microscopy (KPFM), we show that irradiation leads to a local change in surface potential and find that both ultra-violet (UV) light and ambient exposure can act to restore the conductivity. We propose that the electron beam injects negative subsurface charge into deep trap states that electrostatically gate the local hole transport. In some cases, local electron-stimulated desorption of electron-accepting surface species may also contribute.
Wood et al. (Fri,) studied this question.