Schottky diode based on large area CVD-grown WSe₂

Two-dimensional transition metal dichalcogenides have attracted great attention due to their unique optoelectronic applications. Of these, tungsten diselenide (WSe₂) is a semiconductor with a trigonal structure, and a small bandgap ~1.6eV. Here we report electronic transport measurements of CVD-grown WSe₂ configured as a Schottky diode. To prepare the device, the WSe₂ film was transferred onto an n-doped Si/SiO₂ wafer with pre-patterned gold electrodes over the oxide surface. The diode parameters were analyzed using the standard thermionic emission model of a Schottky junction. Results obtained at room temperature include a forward turn-on voltage of ~0.46 V, ON to OFF current ratio at ± 1 V of ~1100, barrier height of 0.41 eV and an ideality parameter of n~1.3. The device was tested as a half-wave rectifier showing a rectification ratio of 1150 with an output/input voltage ratio of 46.3%. Efforts to investigate the temperature-dependent transport mechanisms of the device will also be presented.