Berlin 2008 – wissenschaftliches Programm

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DS: Fachverband Dünne Schichten

DS 21: High-k Dielectric Materials - Synthesis, Properties, Applications

DS 21.2: Hauptvortrag

Mittwoch, 27. Februar 2008, 15:00–15:30, H 2032

Are Optical Measurements Sensitive to Quantum Confinement? — •Alain Diebold — College of Nanoscale Science and Engineering, Albany, NY USA

Nanofabrication methods have produced ultra-thin films, nanowires of various cross-sectional shapes, and quantum dots. Characterization of nano-scale materials has proven the existence of quantum confinement or quantum size effects (QSE). Of note to the characterization community is observation of QSE in thin metal films using X-ray Photoelectron Spectroscopy. This presentation emphasizes optical observation of quantum confinement in ultra-thin silicon semiconductor films. The first step in identifying changes in optical properties, especially the dielectric function, is demonstrating that the data is not due to other phenomena such as stress. We show that the blue shift E1 critical point of thin silicon on insulator films is not due to stress. This blue shift is attributed to quantum confinement. We also discuss why energy shifts in E1 smaller than KT can be observed optically.