Chemical Composition and Thermal Stability of Atomic Force Microscope-Assisted Anodic Oxides as Nanomasks for Molecular Beam Epitaxy

Abstract

We have investigated the thermal stability of GaAs-oxides grown by atomic force microscope (AFM)-assisted anodic oxidation to identify the conditions suitable for fabricating oxide nanomasks for molecular beam epitaxy (MBE). The oxides grown at bias voltages, V ox, less than 30 V were desorbed after standard thermal cleaning in MBE, while the oxide patterns fabricated at V ox ≥40 V survived on the GaAs surfaces. From X-ray photoemission spectroscopy, we have found that the better thermal stability of AFM-oxides grown at V ox > 40 V can be attributed to the formation of Ga2O3 and that Ga2O3 can be used as nanomasks for site-controlled MBE growth.

Size-Limiting Effect of Site-Controlled InAs Quantum Dots Grown at High Temperatures by Molecular Beam Epitaxy

“…Details of the AFMassisted oxidation process have been reported elsewhere. 22) Nanoholes were formed by wet chemical etching of the oxide dots. The obtained nanoholes were typically $4 nm deep and had a diameter of $100 nm.…”

Nanoscale wafer patterning using SPM induced local anodic oxidation in InP substrates

“…The tip voltage affects the depth that these reactive ions can penetrate into the surface and therefore determines the maximum depth that the oxide grows to. The main parameters affecting the dimensions of the oxide formed via LAO and therefore nanohole dimensions are the applied tip bias [14], and humidity [15], in addition to tip-sample distance [16], tip radius [17], and tip writespeed [18].…”