Energy Band Diagram and Current Transport Mechanism In p-MgO/n-Ga4Se3S.

A p-n heterojunction made of MgO and Ga4Se3S single crystal has been successfully produced. The current–voltage curve analysis has shown that the current conduction mechanism is mostly governed by the Richardson–Schottky mechanism. The width of the effective interface region of the p-n junction was found to be 3.72\times 10^-5 cm. The work function and the electron affinity of the Ga4Se3S crystals were also determined as 4.32 and 3.96 eV, respectively. On the other hand, the capacitance–voltage curve analysis, which was carried out in the power range that extends from Bluetooth to WLAN power outputs, reflected a built-in voltage of 0.48 eV and density of noncompensated carriers of 8.2\times 10^16 \mathrmcm^-3 . The device is observed to exhibit a wide range of negative resistance associated with the tunneling of charged particles at reverse biasing down to $\sim 1.28$ V. At that voltage, when exposed to a He–Ne laser beam of $\sim 3$ mW, the device reflected a responsivity of $\sim 80.$ The charge storability increased and the $I$ – $V$ characteristics are significantly shifted. These properties are promising because it indicates the applicability of these tunneling devices in optoelectronics. [ABSTRACT FROM PUBLISHER]