|About this Abstract
||Materials Science & Technology 2013
||Semiconductor Heterostructures: Theory, Growth, Characterization, and Device Applications
||Structure and Composition Peculiarities of GaN/AlN Multiple Quantum Wells and GeSi Quantum Rings by EXAFS Spectroscopy
||Simon Erenburg, Svetlana Trubina, Konstantin Zhuravlev, Timur Malin, Anatolii Dvurechenskii
|On-Site Speaker (Planned)
EXAFS (Extended X-ray Absorption Fine Structure) above the GaK and GeK edge have been used to study the local structure of heterointerfaces in Ge/Si and GaN/AlN structures grown by molecular beam epitaxy. Thickness of AlN and GaN layers in MQWs (multiple quantum wells) were evaluated using HRTEM, X-ray diffraction and Raman- spectroscopy. The Ga-Ga interatomic distance in MQWs is lower than that in the bulk GaN due to elastic compression of GaN layers in MQWs. The Ga-Al interatomic distance in thick MQWs is too long (about 0.1 Angstrom longer than typical values for AlGaN alloys). An heterointerfaces intermixing degree depends on total thickness of MQWs. It was found for Ge/Si QRs (quantum rings) that in the first priming phase of growth Ge atoms concentration is ≈ 25%. With further growth (applying the base layers) Ge concentration increases up to 35-45%, depending on the temperature of deposition (610 - 550 °C).
||Planned: Journal of Electronic Materials