Au在Si表面的成膜质量对金属辅助化学刻蚀法制备硅纳米线至关重要。以Ti、Cr作为浸润层, 可显著改善Au在硅表面的成岛趋势, 获得优质的Au膜并大幅度减少Au的使用量。同时, 针对加入Ti、Cr后对Au辅助化学刻蚀影响的研究表明, Cr在刻蚀液中是稳定的, 因此阻碍了Au催化刻蚀反应, 而Ti与反应溶液快速反应, 不影响Au对Si衬底化学刻蚀的催化作用。基于以上工作, 以PS球为模板沉积制备Ti/Au(3nm/20nm)优质膜, 使用金属辅助化学刻蚀, 制备了有序的Si纳米线阵列。

The quality of gold film is critical to the preparation of Si nanowires by metal-assisted chemical etching(MACE). The introduction of Ti and Cr as a wetting layer on Si substrate can suppress the tendency to form 3-D islands of Au atoms. Hence, high quality Au film with less usage of raw material can be obtained by this method. Further investigations of the Ti and Cr wetting layer on the morphology of etched Si by Au-assisted chemical etching show that: Cr is stable in etching solution and can block the reaction, while Ti reacts rapidly with etching solution and hereby doesn’t prevent the catalyzing etching effect on Si substrate of Au layer. Accordingly, gold film with good quality was prepared by depositing 3nm/20nm Ti/Au with polystyrene(PS) sphere template, then orderly controlled Si nanowires array was prepared through MACE.