LAUSR

Dark current transport mechanism associated with acceptor concentration in GaAs-based blocked-impurity-band (BIB) detectors has been investigated. Device structure, numerical models and simulation techniques are described in detail. By careful model and parameter calibration, the numerical simulation is completely consistent with the analytical calculation, proving the validity of simulation methods. Our results reveals that the carrier-transport modes of GaAs-based BIB detectors can be classified into two categories (i.e., electron current and hopping current), and the hopping current can be neglected compared with the electron current. Besides, it is demonstrated that the dark current of GaAs-based BIB detector is dominated by the drift–diffusion current and the generation-recombination current, and the both current components are monotonically decreasing functions of the acceptor concentration.