The Effects Of Buffer Layers On Structures And Properties Of Sic Thin Films

The amorphous SiC thin films were prepared on the Si and stainlesssteel substrates at room temperature by substrate bias-assisted RFmagnetron sputtering, then changed into crystalline SiC thin films throughdifferent annealing processes. The results show that a higher bias canimprove growing rate and quality of SiC thin films greatly, and also, hinderthe formation of SiOx. Moreover, the higher RF power is in favor of thegrowth of SiC thin film, and the threshold of RF sputtering power is about130W under0.5Pa sputtering pressure. The quantity of SiOxin the SiC thinfilms is reduced with the decrease of sputtering pressure. With a two-stagebias-assisted magnetron sputtering, the growth rate of the SiC thin filmsincreases and the crystalline quality is greatly improved.In order to obtain the high quality SiC thin films on the stainless steel,we analyzed the adhesive mechanism. We researched the grown processes ofSiC thin films on the stainless steel with the Al₂O₃and TiO₂buffer layersand their performance, then solved the problem of adhesion between SiCthin films and stainless steels efficiently. The structure, morphology,mechanical properties and optical properties of the SiC thin films werecharacterized by XRD, AFM, FTIR, and so on. The main contents are asfollows:The first chapter outlines the SiC crystal structure, basic properties,mechanical, physical and chemical properties. Moreover, the preparedmethod and research status of SiC are suggested, at last, the main contentand the innovation point are given.The second chapter introduces the development and the principle of RFmagnetron sputtering, and describes the growth processes, mechanism andthe basic characterization methods of thin films.The third chapter discusses the effects of process parameters, such assputtering pressure, sputtering power and bias on SiC thin films grown onSi substrate, then XRD, XPS, AFM, and FTIR of SiC thin films aremeasured, moreover, two-stage bias-assisted magnetron sputtering is introduced to prepare SiC thin films and this method can improve thequality of SiC thin films.The forth chapter researches basic principles about thin film adherenceto substrate and buffer layer. How to select the buffer layer? The physicaland chemical properties of Al₂O₃and TiO₂buffer layers are studied in thispaper.The fifth chapter compares the SiC thin films with Al₂O₃/SiC and,TiO₂/SiC thin films on stainless steel substrates by SEM, XRD and so on.The effects of buffer layer on SiC thin films are obtained by measuring theirstructure, surface topography, corrosion resistance and adhesion ofsubstrate to film.The sixth chapter is conclusions and outlooks.