Preparation And Characterization Of Metal-doped Yttrium Oxide Films

Yttrium oxide?Y₂O₃?is a rare-earth metal oxide.?Y₂O₃?is also a promising anti-oxidation material for diamond with good physical,chemical and anti-oxidation properties.And,Y₂O₃ thin film has been widely used in photoelectric equipments and semiconductor devices because of its high transmissivity and excellent dielectric property.In this thesis,Y₂O₃ films were prepared on Si?100?and glass substrates by magnetron sputtering.And the structure,morphology,composition and optical characteristics of Y₂O₃ films were studied by X-ray diffraction?XRD?,scanning electron microscopy?SEM?,energy dispersive spectroscopy?EDX?and UV-visible near-infrared spectrophotometer respectively.The Y₂O₃ films grown on Si?100?substrates and glass substrates both have monoclinic structure,but there are some differences in crystallinity and preferred growth direction.The Y₂O₃ films deposited on the glass substrates with poor crystallinity have a preferential growth orientation of?202?,while the Y₂O₃ films deposited on Si substrates with good crystallinity have a preferential growth orientation of?111?.The crystallinity and stoichiometry of Y₂O₃ films deposited on Si substrates were both improved after annealing,and a phase transition from monoclinic phase to cubic phase is found in annealed Y₂O₃ films.Sn-doped Y₂O₃?Sn:Y₂O₃?films and V-doped Y₂O₃?V:Y₂O₃?films were pre-pared by magnetron co-sputtering.Under certain conditions,the crystallinity of Y₂O₃ films is improved after Sn and V doping.The grain arrangement of the V:Y₂O₃ films deposited on glass substrates with a clear columnar structure is more compact than the un-doped Y₂O₃ films with a flaky structure.In the case of a doping time of 15 min,a cube phase structure appeared in V:Y₂O₃ films,which is of great significance to improve the stability.The additional Sn and V also have a certain influence on the optical properties of Y₂O₃ films.After Sn doping,the transmittance of Y₂O₃ films increases in near infrared region;in addition,Sn and V doping can both increase the bandgap of Y₂O₃ films,the calculated band gap values of Sn:Y₂O₃ and V:Y₂O₃ films are 4.94-5.06 eV and 5.06-5.14 eV,respectively.