AFM诱导正十八硫醇在金基底上的选择性生长

AFM was employed for fabricating positive organic pattern on gold surface. In this procedure, 1-octadecanethiol was adsorbed onto AFM tip firstly and then transported to gold surface during the scanning process. The transported molecules could spontaneously adsorbed onto gold surface to form a monolayer. The selective transport was controlled by the scanning parameter, such as scanning speed and tip-substrate interaction. It was found that the relative humidity plays very important roles on the deposition process, the higher the humidity, the higher the possibility that deposition happens. The dependence of deposition on the humidity suggests that the 1-octadecanethiol molecule is transported through the water layer on the gold surface. Meanwhile, the optimal deposition condition also depends on the characteristics of AFM tip.