New process for high optical quality InAs quantum dots grown on patterned GaAs(001) substrates

TL;DR

This paper introduces a novel patterning process combining UV-ozone oxidation, chemical etching, and laser interference lithography to produce high-quality InAs quantum dots on patterned GaAs substrates, enabling customized quantum dot arrays.

Contribution

It presents a new patterning technology that achieves high optical quality InAs quantum dots on patterned substrates, matching those on flat surfaces.

Findings

Ordered InAs/GaAs quantum dot arrays with high optical quality

Patterning technology enables customized quantum dot geometries

Quantum dots on patterned substrates have optical properties comparable to flat substrates

Abstract

This work presents a selective ultraviolet (UV)-ozone oxidation-chemical etching process that has been used, in combination with laser interference lithography (LIL), for the preparation of GaAs patterned substrates. Further molecular beam epitaxy (MBE) growth of InAs results in ordered InAs/GaAs quantum dot (QD) arrays with high optical quality from the first layer of QDs formed on the patterned substrate. The main result is the development of a patterning technology that allows the engineering of customized geometrical displays of QDs with the same optical quality as those formed spontaneously on flat non-patterned substrates.