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In this book, we study the photoexcitation-photoemission processes in oxidized porous Si and nanoscale-Si particle-embedded in Silicon oxide system and we verify the use of more than one type of photoluminescence mechanism model used for describing the photoluminescence in this system. For this study the photoluminescence is considered due to photoexcitation and recombination of photo-carriers in nanoscale Si/SiO2 system, in nanoscale Silicon partcle, in luminescence centers (defects and impurities) in Silicon oxide layers surrounding the nanoscale Silicon particle and in both the nanoscale Silicon particle and luminescence centers. We did some calculations and developed a model to verify the multiple mechanism models to describe the PL in the system in to consideration. The book will be of fundamental help to those who want to master the PL mechanism in silicon Nan particles and study the quantum effects on the Luminescence behaviour of semiconductor materials.

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Wondwosen Tilahun M. B.Sc, M.Sc, Applied Physics, Addis Ababa university, ethiopia, M.Sc in Elect.Engineering,specialization in Photonics, University of Gent, Free University of Brussels, Belgium and KTH, Sweden. PhD student at KTH

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