High-performance planar light-emitting diodes

High-speed planar light-emitting diodes fabricated within a single high-mobility quantum well are demonstrated. Devices were fabricated by photolithography and wet chemical etching starting from p-type modulation-doped Al0.5Ga0.5As/GaAs heterostructures grown by molecular beam epitaxy. Electrical and optical measurements from room temperature down to 1.8 K show high spectral purity, high external efficiency, and extremely short recombination times of the order of 50 ps. Time-resolved electroluminescence measurements demonstrate subnanosecond modulation time scale. (C) 2003 American Institute of Physics.