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Abstract: Nanocrystalline zinc films were deposited on gold coated borosilicate glass substrates by thermal evaporation method using zinc powders as the source material and then treated with argon plasma at various temperatures. From X-ray diffraction study, the as-deposited films are found to be metallic Zn and polycrystalline in nature. The crystalline nature improves with the increase of temperature up to 200°C and decreases with the further increase of temperature to 300°C. The binding energy observed for Zn 2p3/2, and the binding energy separation between Zn 2p3/2 and Zn 2p1/2 in the X-ray photoelectron spectrum indicate that the films are metallic zinc films. Transmission electron microscopic study shows hexagonal shaped grains having size ∼58nm upon treatment with Ar plasma. It is clearly shown the grain growth and distinct grain boundary with the increase in temperature. The average Young''s modulus (E) and hardness (H) are measured to be 84GPa and 4.0GPa for as-deposited film, whereas 98GPa and 5.8GPa for plasma treated film at 200°C. The enhancement in mechanical properties is attributed to improvement in crystalline nature of the film and better interlinking between grains and boundaries. [Copyright &y& Elsevier]

• Temperature dependent dielectric studies on SrTiO 3 /SrRuO 3 /GaFeO 3 (STO/SRO/GFO) suggest the ferroelectric-relaxor behavior. • Magnetization vs Temperature measured both at field-cooled (FC) and (zero-field-cooled) ZFC shows large bifurcation with transition temperature at 240 K. • The clear and reversible out-of-phase contrast is seen in the piezoresponse force microscopy (PFM) phase and amplitude images. • Polarization vs electric field (P-E) hysteresis loop study on STO/SRO/GFO/Pt reveals the remanent polarization of polarization of ∼30 µC/cm2 and coercive field (E C) of 0.09 MV/cm. We report a detailed investigation on magnetic and electrical properties of the multiferroic GaFeO 3 (GFO) thin films grown on SrRuO 3 (SRO) buffered SrTiO 3 (1 1 1) substrates. The magnetic transition temperature (T c) of GFO thin films is observed ∼240 K, which is higher by 20 K than in GFO ceramic. The clear and reversible out-of-plane phase-contrast seen in the Piezoresponse Force Microscopy (PFM) phase and amplitude images measured within positive and negative poling confirms the polarization reorientation and hence piezoelectric nature of the compound. The temperature and frequency dependence of permittivity studies demonstrates the relaxor behavior of these thin films. The observed near room temperature (RT) magnetic phase transition with RT piezoelectric nature of these thin films elucidates the possible potential candidates for a multiferroic world with spintronics device applications. [ABSTRACT FROM AUTHOR]