title: Improvement of phase stability and accurate determination of optical constants of SnO thin films by using Al2O3 capping layer.
abstract: In this letter, it is proposed that the usage of Al(2)O(3) capping layer can tremendously improve the phase stability of SnO thin films, which allows the accurate determination of the optical constants of the SnO films without the perturbation arising from impurity phases. For the SnO films, the refraction index and extinction coefficient are significantly influenced by the crystallinity. The nondirect optical bandgap of the amorphous SnO films is determined to be 2.27 eV, whereas two nondirect optical transitions are observed in the polycrystalline SnO films and the corresponding gap energies are estimated to be 0.50 and 2.45 eV, respectively.
authors.forename: Ling Yan
authors.initials: LY
authors.lastname: Liang
authors.forename: Zhi Min
authors.initials: ZM
authors.lastname: Liu
authors.forename: Hong Tao
authors.initials: HT
authors.lastname: Cao
authors.forename: Yuan Yuan
authors.initials: YY
authors.lastname: Shi
authors.forename: Xi Lian
authors.initials: XL
authors.lastname: Sun
authors.forename: Zheng
authors.initials: Z
authors.lastname: Yu
authors.forename: Ai Hua
authors.initials: AH
authors.lastname: Chen
authors.forename: Hai Zhong
authors.initials: HZ
authors.lastname: Zhang
authors.forename: Yan Qun
authors.initials: YQ
authors.lastname: Fang