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Updated: Jan 26, 2026

Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots
Published on: November 1, 2013
Photo-Atomic Layer Etching of GaAs/AlGaAs Nanoheterostructures
Mohammad R Aziziyan1, Hemant Sharma1, Jan J Dubowski1
1Laboratory for Quantum Semiconductors and Photon-based BioNanotechnology, Interdisciplinary Institute for Technological Innovation (3IT), CNRS UMI-3463, Department of Electrical and Computer Engineering, Université de Sherbrooke , 3000, boul. de l'Université , Sherbrooke , Québec J1K 0A5 , Canada.
Abstract:
Photo-atomic layer etching (photo-ALE) of GaAs and AlGaAs semiconductors was investigated in deionized H2O and aqueous solution of NH4OH under weak excitation conditions ( P ≈ 20 mW/cm2). The process is based on digital photocorrosion in a processed solution and a negligible corrosion during the light-off phase employed for dissolution of the photocorrosion products. An inductively coupled plasma mass spectroscopy (ICP-MS) analysis revealed that photo-ALE of GaAs in an aqueous solution of NH4OH proceeds linearly with the number of reaction cycles, typically at ∼0.1 nm/cycle, and with the light-off phase as short as 22 s sufficient to entirely dissolve the photocorrosion products generated during a 3 s irradiation. In agreement with the ICP-MS data, the constant photo-ALE rates in NH4OH were also demonstrated in situ with the photoluminescence measurements. Our results suggest that the congruent decomposition of III-V materials and the etching of deep structures with atomic layer resolution could be facilitated by switching in situ between different etching environments.
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