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Undoped and In-doped SrTiO_3(STO) films were grown on MgO/TiN/Si(100) substrates by pulsed laser deposition(PLD).The growth mechanism,crystallinity,surface morphology,and UV- Raman spectra of the films were studied.Results indicate that undoped STO films show high quality crystalline structure with highly (200) orientation.With Indium doping,the crystallinity of the STO film deteriorate,the first order Raman peaks increase indicating the breaking of crystal symmetry,and the film growth mode change from the layer-by-layer mode to island-layer mixed one,resulting in the roughening of the film surface.Furthermore,the crystallinity and (200) orientation of In-doped STO film can be enhanced significantly by introducing an undoped STO buffer layer.

Ag nanoparticles were prepared on the surface of multi-walled carbon nanotubes( MCNTs) by thermal evaporation deposition at room temperature. The morphology and microstructures of Ag/CNTs composites were characterized by SEM,XRD,TEM and HRTEM. The measurement results verify the nanocrystal shape of Ag nanoparticles on the MCNTs. Ag nanoparticles are distributed evenly on the MCNTs and the density of Ag nanoparticles reaches 10(11) cm(-2). Ag nanoparticles present round or elliptical patterns and the round particles have larger diameter than the elliptical ones. The MCNTs are deformed at where Ag nanoparticles grow, which should be attributed to the interaction between Ag nanoparticles and MCNTs during the evolution. The heterojuntion materials are formed by the deformed MCNTs and as-grown Ag nanoparticles. It is found that the heterojuntion materials share mutual connections and constitute a net structure because the chemical bonds between Ag nanoparticles and MCNTs have fixation on reciprocal chiasmata MCNTs. The as-prepared 0-1 dimensional materials have promising applications in sensors, catalysis and optoelectronic devices.