Fabrication of GaNxAs1-x Quantum Structures by Focused Ion Beam Patterning

TL;DR

This paper introduces a new method for fabricating GaNxAs1-x quantum dots and wires using focused ion beam patterning, involving ion implantation and rapid thermal annealing to selectively amorphize regions.

Contribution

It demonstrates a novel ion beam patterning technique to create quantum structures in GaNxAs1-x films, enabling controlled fabrication of quantum dots and wires.

Findings

Ion beam patterning effectively amorphizes targeted regions.

Quantum structures can be formed by adjusting implantation patterns.

Damage thresholds influence the quality of the fabricated structures.

Abstract

A novel approach to the fabrication of GaNxAs1-x quantum dots and wires via ion beam patterning is presented. Photomodulated reflectance spectra confirm that N can be released from the As sublattice of an MBE-grown GaNxAs1-x film by amorphization through ion implantation followed by regrowth upon rapid thermal annealing (RTA). Amorphization may be achieved with a focused ion beam (FIB), which is used to implant Ga ions in patterned lines such that annealing produces GaAs regions within a GaNxAs1-x film. The profiles of these amorphized lines are dependent upon the dose implanted, and the film reaches a damage threshold during RTA due to excess Ga. By altering the FIB implantation pattern, quantum dots or wires may be fabricated.