GaAs surface passivation for InAs/GaAs quantum dot based nanophotonic devices.

Several passivation techniques are developed and compared in terms of their ability to preserve the optical properties of close-to-surface InAs/GaAs quantum dots (QDs). In particular, the influence of N-passivation by hydrazine chemical treatment, N-passivation by hydrazine followed by atomic layer deposition (ALD) of AlO and use of AlN deposited by plasma-enhanced ALD are reported. The effectiveness of the passivation is benchmarked by measuring the emission linewidths and decay rates of photo-carriers for the near-surface QDs.