Ion implanted lateral In.2Ga.8As/GaAs strained-layer superlattice photodetector

A Be⁺implanted lateral In.2Ga.8As/GaAs SLS photodetector has been fabricated. The devices exhibit good reverse bias characteristics with dark current of less than 6nA at -60 V. Quantum efficiency measurements indicate an uncoated external value of 50 percent at -20V. Position resolved photocurrent measurements show that carrier collection occurs over a large area (100µm × 250µm at -50V) with capacitance values less than 1 pF. This is the first demonstration of a photodetector which utilizes the preferred direction of conduction that occurs in superlattice structures.