High reproducibility for deep-quantum-well resonant tunnelling diodes grown by metal organic chemical vapour deposition

Deep-quantum-well AlGaAs/LnGaAs/GaAs resonant tunnelling diodes (RTDs), rel ying on resonant tunnelling through the second energy level of the quantum well, are found to have significantly lower sensitivity to the possible var iations in thickness of the barriers than conventional devices: the peak cu rrent density of deep-quantum-well structures decreases by a factor of 1.48 for each monolayer increase in the total barrier thickness compared with a factor of 2.27 for state-of-the-art InP-based devices. Thus these structur es can be fabricated much more reproducibly than conventional RTDs.