Improved performance of InAlN-based Schottky solar-blind photodiodes

The authors report the growth of InxAl1−xN with high crystal quality by metal organic chemical vapor deposition, the Pd/InxAl1−xN Schottky contacts with reverse current densities as low as 6.0×10−7 A/cm2 at −5 V and 2.1×10−5 A/cm2 at −10 V, and consequently significant improvement in the performance of InAlN-based Schottky solar-blind photodiodes with peak responsivity of 133 mA/W at 242 nm, corresponding to a quantum efficiency of 68.5%. The illumination is detectable under the intensity as weak as 10 nW/cm2. The rejection ratios by 300 nm are one order of magnitude for 10 nW/cm2 illumination and three orders of magnitude for 1 μW/cm2 illumination.