the effect of thermal annealing on structural, morphological and optical features of batio3 thin film assisted by e-beam pvd technique

The work reported in this paper was focused on the investigation of surface morphological,microstructural, and optical features of polycrystalline batio3 thin film deposited on p-type si < 100 > substrateusing e-beam pvd (physical vapor deposition) technique. the influence of annealing on the surface morphology ofthe thin film was analyzed by x-ray diffraction, atomic force microscopy and scanning electron microscopy. whenthe annealing temperature was increased from as-deposited to 800 °c there was a significant growth in the grainsize from 28.407 to 37.89 nm. this granular growth of batio3 made the thin film appropriate for nanoelectronicdevice applications. the roughness of the annealed film was increased from 31.5 to 52.8 nm with the annealingtemperature. the optical bandgap was computed using kubelka-munk (km) method which was reduced from 3.93to 3.87 ev for the as-deposited to the 800 °c annealed film. the above reported properties made the annealed filmsuitable for optoelectronic applications. for polycrystalline batio3 thin film the refractive index varied from 2.2 to1.98 from 400 to 500 nm and it was 2.05 at 550 nm wavelength. the broad peaks in raman spectra indicated thepolycrystalline nature of the thin film. it was also observed that with the annealing temperature the intensity of theraman peaks increased. from these results, it was proved that annealing significantly improved the crystallinity,microstructural, surface morphological and optical features of the barium titanate thin film which made it suitableas potential sensors in biomedical applications as it is cost-effective, lead-free and environment friendly material.