Influence Of Ga Doping On The Structural, Optical And Electrical Properties Of Ba0.6Sr0.4tio3 Thin Films
V. Eswaramoorthi, Sony Sebastian, R. Victor Williams
Keyword: BST, Dielectric properties, Optical properties, Structural properties, Sol-gel, Thin film, Tunability.
Abstract: The effects of Ga doping on the structural, optical and electrical properties of sol-gel routed Ba0.6Sr0.4TiO3 thin films on quartz and silver coated quartz substrates have been investigated. XRD analysis indicates that the crystallite size decreases with increase in dopant concentration and the strain in the film is compressive in nature. SEM analysis reveals that the surface smoothness improves with dopant concentration. EDX analysis reveals the presence of gallium in the doped material. The dielectric constant and dielectric loss decrease with dopant concentration whereas the tunability and figure of merit increase with dopant concentration. The UV-Vis transmission spectrum analysis shows that the transmittance and the refractive index of the film decrease with dopant concentration. The band gap of the film increases with dopant concentration.
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