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High-performance planar light-emitting diode

Marco Cecchini·Vincenzo Piazza·Fabio Beltram·Marco Lazzarino·M. B. Ward·A. J. Shields·H. E. Beere·D. A. Ritchie
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Abstract

Planar light-emitting diodes (LEDs) fabricated within a single high-mobility quantum well are demonstrated. Our approach leads to a dramatic reduction of radiative lifetime and junction area with respect to conventional vertical LEDs, promising very high-frequency device operation. Devices were fabricated by UV lithography and wet chemical etching starting from p-type modulation-doped AlGaAs/GaAs heterostructures grown by molecular beam epitaxy. Electrical and optical measurements from room temperature down to 1.8 K show high spectral purity and high external efficiency. Time-resolved measurements yielded extremely short recombination times of the order of 50 ps, demonstrating the relevance of the present scheme for high-frequency device applications in the GHz range.

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Marco Cecchini, Vincenzo Piazza, Fabio Beltram, Marco Lazzarino, M. B. Ward, A. J. Shields, H. E. Beere, D. A. Ritchie. 2002-07-31. High-performance planar light-emitting diode. https://doi.org/10.1063/1.1540244

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