Electrical Properties and Photosensitivity of Multi-Barrier Photodiode Structure Based on Semi-Insulating GaAs

The present work reports the detailed electrical properties and photosensitivity of multi-barrier photodiode structures based on semi-insulating gallium arsenide. The dependence of the dark current on the voltage is linear up to 70 V when p-n-junction is reverse biased, and is linear up to 300 V when one is forward biased. The structure has a high sensitivity in the region of wavelength which are larger than the red border, determined by the band gap of the base region material. The photosensitivity of the structure corresponds to the photoemission of non-equilibrium charge carriers through a metal-semiconductor rectifying barrier.