不同热处理条件下的Ag/Ni超晶格薄膜层状结构的X射线衍射研究

用Ｘ射线衍射法，对经不同条件热处理后的Ａｇ／Ｎｉ超晶格薄膜的结构进行研究．结果表明，未经热处理的超晶格膜显示良好的人工双元素层调制周期性，且存在［１１１］晶向垂直于膜面的织构．升温时的应变弛豫使超晶格膜的晶格沿垂直于膜面方向发生轻微收缩，直至达平衡态．热处理形成新晶粒，其取向不再严格有序，减弱了薄膜的［１１１］织构．加热所激发的原子长程扩散导致一些元素层厚度减小并趋于消失，而另外的元素层厚度增大，从而使人工调制周期性逐渐被破坏；原始态超晶格膜元素层的厚度越大，则周期结构的热稳定性相应也越高，这部分归因于原子扩散长度与元素层厚度成正比关系

X-Ray Diffraction Study on the Structure of Ag/Ni Superlattices Heat-Treated under Different Conditions

X-ray diffraction study on the structure of Ag/Ni superlattices with different layer thicknesses and heat treatment under different conditions has been performed. The as-deposited films exhibit good bilayers modulated periodicity and texture along the perpendicular direction. The average interplanar spacings of the films contract slightly toward equilibrium during heating by lattice strain relaxation. Heating also induces the formation of new grains with randon orientations, which reduce the texture of the film. The atomic diffusions result in some of the elementary layers getting thicker, while others getting thinner and finally disappearing, thus gradually destroying the artificial bilayered periodicity. The thicker the bilayers, the more stable the superlattices are, since the diffusion length is proportional to the layer thickness.