Transient atomic behavior and surface kinetics of GaN

Abstract

An in-depth model for the transient behavior of metal atoms adsorbed on the surface of GaN is developed. This model is developed by qualitatively analyzing transient reflection high energy electron diffraction (RHEED) signals, which were recorded for a variety of growth conditions of GaN grown by molecular-beam epitaxy (MBE) using metal-modulated epitaxy (MME). Details such as the initial desorption of a nitrogen adlayer and the formation of the Ga monolayer, bilayer, and droplets are monitored using RHEED and related to Ga flux and shutter cycles. The suggested model increases the understanding of the surface kinetics of GaN, provides an indirect method of monitoring the kinetic evolution of these surfaces, and introduces a novel method of in situ growth rate determination.

An aberration-corrected STEM study of structural defects in epitaxial GaN thin films grown by ion beam assisted MBE

“…Since the energy difference between the z-GaN and w-GaN is very small (Ito, 1998;Yeh et al, 1992), the reasons for the nucleation of z-GaN on top of w-GaN crystallites can be various. It is known that a low substrate temperature of 630 • C and Ga-rich growth conditions prefer the nucleation of z-GaN phase (Moseley et al, 2009;Sienz et al, 2004a). However, similar formation of z-GaN close to the SiC substrate was observed during the growth of GaN thin films in N-rich conditions .…”

Особенности спектров фотовозбуждения эпитаксиальных слоев InN, выращенных методом молекулярно-пучковой эпитаксии с плазменной активацией азота

“…Во время фазы роста в металлобогащенных условиях на поверхности скапливалось 1.5−2 монослоя (МС) металлического In. Согласно теории [17], при росте нитридов в металлобогащенных условиях поверхность роста смачивается 2 МС металла, а остальной излишек металла собирается в капли. Ограничение в накоплении 1.5−2 монослоя In во время фазы роста в металлобо-гащенных условиях необходимо для подавления обра-зования капель металлического индия на поверхности и, таким образом, проблем с формированием кластеров металлического In внутри слоя InN [18,19].…”

Pulsed growth techniques in plasma-assisted molecular beam epitaxy of Al Ga1−N layers with medium Al content (x=0.4–0.6)

“…In principle, RHEED allows one to evaluate Ga-coverage on the surface of the growing films [6,13], but these measurements are technically difficult for growth control of the films on rotating substrates.…”