Spectroscopic Study Of The Formation Of Porous Silicon And Its Mosaic Laser Dyes

Porous Silicon (PS)is a kind of material whose preparation method is simple but structure is extremely compkxlts marvelous luminescence phenomenon and property attract many research workers to stud}' it and develop its apparatusesAt present,people still concentrate on fundamental research of P&such as its micro-stnx3ure/ctmation mechanism With deeper research of PS,the subtlety of PS will be discovered.Chapter One of this thesis summarizes die research of PS in the past years in teens of its devdopmentformation nied]amsnyniaio-stnidure,optical propertyjuininescence mechanism and prospects of application.Chapter Two firstly introduces the preparation process of PS Jt points out that the interface barrier has an important function in the process-.The interface barrier is just like Schotlky with the barrier parameters affected by the surface conditions and extra-poential,and determines F ions to etch c-SLThen,the effects of sample preparation parametersuch as the content of dectroryte,current density,on PS formation were anaryzedAs a resuh,the preparation conditions were optimized. The charge transfer and photoeletric properties of PS were investigated by photoeletrochemical technkjues.The results show mat the PS fabricated by single crystalline p-Si exhibits photoeletric properties of p-type semiconductors with a higher photocurrent than the original silicon-Due to the unique surface structure,the PS has a particular photocurrent spectrum.This is attributed to the photochangjrapping effect of surface states in the PS. Finally, the photoluminescence of PS is studied Furthermorets for the APSjts photoluminescence can be explained by the model of quantum confinement effectas for the OPS and AOPS.their photoluminescenses can be explained by the modle of me quantum confinement effect and by that of luminescent centre.Chapter Three studies the spectra of laser dye embedded PS and points out the surface of PS has the quality of optical senshiciryJor the particular surface structure can work as the carrier and make the stase of dye molecule change,therefore improve the fluorescence enhanced effects.The embedding process influences the properties of PS and dye and make mem produce the energy transfer effectsTherefbre,developing the complex of PS and laser dye may be a method to improve efficiency and luminescence stability.