Bl结构MoNx薄膜的制备及物理性能研究

我们对以反应性溅射法制备的MoN_x薄膜测量了超导转变温度T_c,电阻率ρ(T)(从T_c起始到300K)。用X射线衍射技术、卢瑟福背散射(RBS)、俄歇谱仪和X射线光电子能谱(XPS)技术对这些样品进行了分析。实验结果表明T_c和ρ(T)随N含量改变而变化。当样品是B1结构时,T_c小于4.2K,而且样品内还有过量的N存在。俄歇分析表明,样品内有O,C杂质存在。这些因素都可能导致T_c很低,ρ(T)呈负的温度系数。关键词：

THE PREPARATION AND PHYSICAL PROPERTIES OF B1 STRUCTURE MoNx THIN FILMS

We have measured the superconducting transition temperature T_c and resistivity ρ(T) (from T_c onset to 300 K) of the reactive sputtered MoN_x thin films. The X-ray diffraction, Rutherford back scattering (RBS), Auger and XPS technique were used for exmination of these specimens. The results showed that T_c and ρ(T) change with the concentration of nitrogen in thin films obviously. For Bl structure or nitrogen-rich samples, T_c is lower than 4.2 K. dρ/dT is negative as temperature is higher than T_c onset. Auger analysis indicated that the existence of oxygen and carbon could be also the reason for very low T_c and semiconducting behaviour in ρ(T) of this kind of thin films.