基于金纳米粒子掩模的硅表面纳米结构加工

利用金溶胶纳米粒子为掩模,结合轻敲模式原子力显微镜（TM AFM）的局域氧化技术和化学湿法腐蚀,对Si表面进行纳米尺度的结构加工,得到柱状和环状纳米结构.实验结果表明,氧化过程中AFM针尖与样品平均间距的大小显著影响后续纳米结构的形状.保持一定的氧化偏压、扫描速度和相对湿度,当针尖与样品间距为7.5 nm时,可得到柱状纳米结构；而当间距减小到5 nm时,则得到带芯环状纳米结构.不同几何形状的纳米结构形成的原因是体系中纳米粒子物理屏蔽效应.

Fabrication of Nanostructures on Si Surface Using Gold Nanoparticle Mask

Using gold nanoparticle as nanooxidation mask, tapping mode atomic force microscope (TM-AFM) nanolithography and wet chemical etching techniques were combined to build nanostructure on Si surface. The nanoparticles were immobilized on mercaptopropyl - trimethoxysilane (MPTS ) - modified silicon surface via Au - S bonding and were exploited as the lithography mask to prevent the AFM tip-induced nanooxidation of MPTS and sil- icon substrate. It was found that the nanostructures formed on Si surface were dependent on the tip-sample separa- tion. With a certain bias voltage, scanning rate and relative humidity, adjusting the separation to 7. 5 nm, nanopillar structures were obtained; while decreasing the separation to 5 nm, nano-ring structures appeared. To explain the for- mation mechanism of these nanostructures, a hard ball model based on nanoparticle physical shielding effect was proposed.