Molecular beam epitaxy of single crystalline GaN nanowires on a flexible Ti foil

TL;DR

This paper reports the successful growth of single crystalline GaN nanowires on flexible Ti foil using plasma-assisted molecular beam epitaxy, demonstrating their potential for flexible optoelectronic devices.

Contribution

It introduces a novel method for growing high-quality GaN nanowires on flexible metal substrates, expanding possibilities for flexible electronics.

Findings

Nanowires are single crystalline as shown by TEM.

Photoluminescence indicates comparable crystalline quality to GaN on Si.

Flexing the substrate does not degrade optical properties.

Abstract

We demonstrate the self-assembled growth of vertically aligned GaN nanowire ensembles on a flexible Ti foil by plasma-assisted molecular beam epitaxy. The analysis of single nanowires by transmission electron microscopy reveals that they are single crystalline. Low-temperature photoluminescence spectroscopy demonstrates that, in comparison to standard GaN nanowires grown on Si, the nanowires prepared on the Ti foil exhibit a equivalent crystalline perfection, a higher density of basal-plane stacking faults, but a reduced density of inversion domain boundaries. The room-temperature photoluminescence spectrum of the nanowire ensemble is not influenced or degraded by the bending of the substrate. The present results pave the way for the fabrication of flexible optoelectronic devices based on GaN nanowires on metal foils.