1. Effects of pulsed laser radiation on epitaxial self-assembled Ge quantum dots grown on Si substrates
- Author
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Jaume Roqueta, Eniko Gyorgy, I. C. Marcus, A. Pérez del Pino, Maria Isabel Alonso, Consejo Superior de Investigaciones Científicas (España), National University Research Council (Romania), and Ministerio de Ciencia e Innovación (España)
- Subjects
Materials science ,Scanning electron microscope ,Analytical chemistry ,Physics::Optics ,Bioengineering ,Epitaxy ,law.invention ,Condensed Matter::Materials Science ,symbols.namesake ,law ,Microscopy ,General Materials Science ,Physics::Atomic Physics ,Electrical and Electronic Engineering ,Spectroscopy ,business.industry ,Mechanical Engineering ,General Chemistry ,Laser ,Mechanics of Materials ,Quantum dot ,symbols ,Optoelectronics ,Raman spectroscopy ,business ,Molecular beam epitaxy - Abstract
11 páginas, 8 figuras.-- El documento en word es la versión post-print del autor., Laser irradiation of Ge quantum dots (QDs) grown on Si(100) substrates by solid-source molecular beam epitaxy has been performed using a Nd:YAG laser (532 nm wavelength, 5 ns pulse duration) in a vacuum. The evolution of the Ge QD morphology, strain and composition with the number of laser pulses incident on the same part of the surface, have been studied using atomic force microscopy, scanning electron microscopy and Raman spectroscopy. The observed changes in the topographical and structural properties of the QDs are discussed in terms of Ge–Si diffusion processes. Numerical simulations have been developed for the investigation of the temperature evolution of the QDs during laser irradiation. The obtained results indicate that the thermal behaviour and structural variation of the nanostructures differ from conventional thermal annealing treatments and can be controlled by the laser parameters. Moreover, an unusual island motion has been observed under the action of subsequent laser pulses., This work was supported by the Spanish National Research Council under contract no. 200960I015 and the Romanian National University Research Council under contract 652, and partially by Spain’s Ministry of Science and Innovation (MICINN) through grant CSD2010-00044. ICM is also grateful to MICINN for a FPI fellowship.
- Published
- 2011