Polymer thin film technology has made tremendous growth due to the range of technological applications such as coatings, light emitting diodes, photodiodes, sensors and batteries. These applications of thin films are possible as they are easy to fabricate and the effects due to confinement and interfacial interactions are responsible for different physical phenomenon that depend on thickness of thin films which cannot be observed in bulk materials. In the present work pure and doped (KNO 3 & MgCl 2) Polyvinyl Alcohol thin films are synthesized using solution casting technique. Electrical conduction in polymers has been studied aiming to understand the nature of the charge transport prevalent in these materials. The variation of conductivity with temperature shows Arrhenius behaviour. Activation energies are calculated from these studies and noted that these depend on the type of dopant material.

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PZT [Pb (Zr 0.52 Ti 0.48 )O 3 ] thin films were prepared on quartz substrate by sol gel spin coating technique. The Zr/Ti ratio was kept at 52/48 which is morphotropic phase boundary (MPB). At MPB both tetragonal and rhombohedral phases coexist and greatly influence the physical properties. In this work the PZT thin films were coated with sol kept at room temperature and at 125°C as 3 (SQ1) and 2 (SQ2) layers. The structural, morphological, compositional and optical properties of coated thin films were studied using X-ray diffraction, scanning electron microscopy (SEM) and UV-Visible spectroscopy. The X-ray diffraction patterns reveal perovskite phase formation for both the films annealed to 660°C. The micro structural parameters such as lattice constant, crystallite size, dislocation density and strain were determined. The grain size increases with increase in sol temperature from 24 to 27 nm. The SEM analysis indicates dense structure of films with good adhesion to the substrate. The cross sectional view of the films provides the thickness of films as 760 and 955 nm. The EDAX data gives the composition of the films. Optical spectra indicate that the films have direct band transitions. The band gap values were dependent on crystallite size and strain. As thickness increases the band gap value decreases from 3.73 to 3.26 eV.