通过混合物理化学气相沉积法,在Cu衬底上制备出长有MgB2超导晶须的厚膜。MgB2晶须顶端直径在1μm左右,根部直径约200nm,长约4μm,整体呈现出六角锥状。通过实验条件的分析,知道衬底表面上方MgB2饱和度不一致,中间较周边低,可能导致了MgB2晶须生长在衬底周边区域。
We have fabricated MgB2 thick film with whiskers existed in the corner on a copper substrate by hybrid physical-chemical vapor deposition (HPCVD) method. The whisker is cone-like and the top diameter is around 1 μm while the bottom is about 200 nm. We analyzed the deposition process, and found that the saturation of MgB2 was not uniform, which on the center of the sample was lower than that on the side. This un-uniformity may trigger the growth of the MgB2 whisker in side of the substrate.