改变VO_2薄膜光学性能的低注量电子辐照方法

Modification in the Optical Properties of VO_2 Thin Films by Low Fluence Electron Irradiation

利用能量为 0 8MeV ,注量为 10 12 /cm2 的低注量电子束辐照VO2 薄膜 ,发现低注量电子辐照显著提高VO2 光学性能的温度响应速度 ,并引起薄膜相变过程中的热滞回线宽度变窄 ,但没有对相变温度点造成明显影响 ;通过对比辐照前后样品 370～ 90 0nm的吸收和透射性能 ,表明辐照后吸光度下降、透射率增加 ,在相变过程中四方相附近出现透射、吸收特性的非稳变化现象 ;利用X射线衍射 (XRD)及拉曼光谱对辐照前后样品进行分析 ,显示低注量电子辐照引起薄膜结构的变化 。

VO2 thin films prepared by vacuum annealing process were irradiated by 1012/cm2 low fluence electron beam with energy of 0.8 MeV. Before and after irradiation the samples were characterized by XRD, UV-VIS and Raman spectroscopy analyses. After electron irradiation the optical response to temperature is increased dramatically, the hysteresis extend is reduced, and the phase transition point is not changed obviously. And the transmittance of 370-900 nm is increased and absorptivity is decreased. The abnormal change of optical properties at metallic boundary was introduced by low fluence electron. Obvious change of XRD patterns and vibration peak were observed in samples before and after irradiation by low fluence electron.