Semiconductors

GaN microrods growth by combined PA-MBE/HVPE method

A. A. Koryakin^a, S. A. Kukushkin^a, Sh. Sh. Sharofidinov^b, L. N. Dvoretskaya^a, I. V. Shtrom^c, A. Yu. Serov^d, K. P. Kotlyar^a, V. V. Lendyashova^a, I. S. Mukhin^a, G. È. Cirlin<sup>ac

a</sup> Alferov Federal State Budgetary Institution of Higher Education and Science Saint Petersburg National Research Academic University of the Russian Academy of Sciences, St. Petersburg
^b Ioffe Institute, St. Petersburg
^c Institute for Analytical Instrumentation, Russian Academy of Sciences, St. Petersburg
^d Saint Petersburg State University

Abstract: The growth of GaN microrods on silicon substrates by the combined PA-MBE/HVPE method was studied. At the first stage, selective-area growth of submicron-sized GaN rods is performed by molecular beam epitaxy with plasma nitrogen activation (PA-MBE). At the second stage, an array of GaN rods is overgrown by hydride vapor-phase epitaxy (HVPE) to increase their size. Controlled HVPE overgrowth of an array of GaN rods is demonstrated, leading to an increase in their average diameter from $\sim$200 nm to $\sim$500 nm and a decrease in the average aspect ratio from $\sim$4 to $\sim$2. The effect of epitaxial overgrowth on the morphological, optical and structural properties of GaN rods array was studied by scanning electron microscopy and low-temperature photoluminescence.

Keywords: PA-MBE, HVPE, GaN microrods, epitaxial overgrowth.

Received: 16.05.2025
Revised: 08.06.2025
Accepted: 10.06.2025

DOI: 10.61011/FTT.2025.06.60937.125-25