Molecular beam epitaxy of semipolar AlN(11\bar{2}2) and GaN(11\bar{2}2) on m-sapphire |
| |
Authors: | Lise Lahourcade Edith Bellet-Amalric Eva Monroy Marie Pierre Chauvat Pierre Ruterana |
| |
Affiliation: | 1. Equipe mixte CEA-CNRS-UJF Nanophysique et Semiconducteurs, DRFMC/SP2M/PSC, CEA-Grenoble, 17 rue des Martyrs, 38054, Grenoble cedex 9, France 2. SIFCOM UMR 6176 CNRS-ENSICAEN, 6 Boulevard du Maréchal Juin, 14050, Caen cedex, France
|
| |
Abstract: | We report on the plasma-assisted molecular-beam epitaxy of semipolar $\hbox{AlN}(11\bar{2}2)$ and GaN( $11\bar{2}2$ ) films on $(1\bar{1}00)$ m-plane sapphire. AlN deposited on m-sapphire settles into two main crystalline orientation domains, $\hbox{AlN}(11\bar{2}2)$ and $\hbox{AlN}(10\bar{1}0),$ whose ratio depends on the III/V ratio. Growth under moderate nitrogen-rich conditions enables to isolate the $(11\bar{2}2)$ orientation. The in-plane epitaxial relationships of $\hbox{AlN}(11\bar{2}2)$ on m-plane sapphire are $11\bar{2}\bar{3}]_{\rm AlN} \vert \vert 0001]_{\rm sapphire}$ and $1\bar{1}00]_{\rm AlN} \vert \vert 11\bar{2}0]_{\rm sapphire}.$ GaN deposited directly on m-sapphire results in ( $11\bar{2}2$ )-oriented layers with ( $10\bar{1}\bar{3}$ )-oriented inclusions. A ~100 nm-thick AlN( $11\bar{2}2$ ) buffer imposes the ( $11\bar{2}2$ )-orientation for the GaN layer grown on top. By studying the Ga-desorption on GaN( $11\bar{2}2$ ), we conclude that these optimal growth conditions corresponds to a Ga excess of one monolayer on the GaN( $11\bar{2}2$ ) surface. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|