Au/Pt/InGaN/GaN Heterostructure Schottky Prototype Solar Cell

A patterned Au/Pt/In0.2Ga0.8N/GaN heterostructure Sehottky prototype solar cell is fabricated. The forward current-voltage characteristics indicate that thermionie emission is a dominant current transport mechanism at the Pt/InGaN interface in our fabricated cell. The Sehottky solar cell has an open-circuit voltage of 0.91 V, short-circuit current density of 7mA/cm^2, and fill factor of 0.45 when illuminated by a Xe lamp with a power density of 300 mW/cm^2. It exhibits a higher short-circuit current density of 30 mA/cm^2 and an external quantum efficiency of over 25% when illuminated by a 20-roW-power He-Cd laser.     

Structural characterization of indium-rich nanoprecipitate in InGaN V-pits formed by annealing

InGaN layers capped with GaN were annealed at 550℃ for 1 hour. During annealing, cracks appeared and dissolved In GaN penetrated through the microcracks into the V-pits to form indium-rich nanoprecipitates. Some precipitates, in-situ annealed under nitrogen ion irradiation by MBE, were confirmed to be cubic GaN on the tops of precipitates, formed by nitriding the pre-existing Ga droplets under nitrogen ions irradiation.