Long-range ordering of III-V semiconductor nanostructures by shallowly buried dislocation networks

TL;DR

This study demonstrates that shallowly buried dislocation networks in GaAs-based heterostructures can induce long-range lateral ordering of III-V nanostructures, with the ordering confirmed by TEM and atomic force microscopy.

Contribution

It reveals how controlled dislocation networks can be used to achieve ordered nanostructures in III-V semiconductor systems.

Findings

Nanostructures are ordered by the dislocation network's stress field.

The dislocation network is formed by wafer bonding to accommodate crystal misorientations.

Ordered nanostructures have matching dimensions and orientations with the dislocation network.

Abstract

We account for lateral orderings of III-V nanostructures resulting from a GaAs/InAs/InGaAs/GaAs sequence grown on GaAs by metallorganic vapour phase epitaxy at two different temperatures. For both samples, the ordering is induced by the stress field of a periodic dislocation network (DN) shallowly buried and parallel to the surface. This DN is a grain boundary (GB) that forms, between a thinGaAs layer (onwhich growthwas performed) and aGaAs substrate joined together by wafer bonding, in order to accommodate a tilt and a twist between these two crystals; both these misorientations are imposed in a controlled manner. This GB is composed of a one-dimensional network of mixed dislocations and of a one-dimensional network of screwdislocations. For both samples, the nanostructures observed by transmission electronmicroscopy (TEM) and atomic forcemicroscopy are ordered by the underlyingDNobserved byTEMsince they have same dimensions andorientations as the cells of the DN.