M/Si-GaAs/M diode: Role of the metal contact in electrical transport, a-particle and photon detection

M/Semi-insulating (SI) GaAs/M diodes with novel Mg-based metallization are investigated using current-voltage measurement, ?-particle and photon detection. An anomalous decrease of the reverse current and peculiar photon spectra has been observed with such contact explainable by a strong electron accumulation due to the creation of a quasi-degenerate region at the Mg/SI-GaAs interface.