不同环境中X射线激光Yb靶表面氧化研究

CHARACTERIZATON OF THE OXIDATION OF Yb FILM TARGETS EXPOSED TO VARIOUS ATMOSPHERE

用电子束蒸发方法淀积制备 X射线激光稀土元素 Yb薄膜靶 ,将薄膜靶在不同的环境气氛中进行氧化。用 X射线光电子谱 ( XPS)、俄歇电子谱 ( AES)和 X射线衍射 ( XRD)方法研究了 Yb薄膜靶表面氧化层的元素价态、组分和微观结构。发现薄膜表面氧化层中存在分层结构 ,干燥空气中储存的 Yb薄膜表面氧化层由表及里的组分依次为化学吸附水、氢氧化物、氧化物及金属元素。表面氢氧化物和氧化物以非晶态形式存在。潮湿空气中水分是薄膜靶氧化速率增加的主要原因。

Rare earth Yb film targets were prepared on to glass substrates with electron beam evaporation, and were exposed to various oxidation atmosphere. The valance, species, morphology and the structure of the oxide layer were studied with X ray photon electron spectroscopy, Auger electron spectroscopy, and X ray diffraction. The surface of the films is found to have a layer structure, with the oxide layer covered by a hydroxide layer and adsorbed layer. The hydroxide and oxide layer are amorphous, the water in the oxidation atmosphere is the key factor resulting the increase of the Yb film oxidation rate.