基于AFM氮化硅探针刻蚀方法制作聚碳酸酯纳米光栅

Fabrication of Polycarbonate Nano-Grating Using AFM Scratching Method with Silicon Nitride Tips

基于原子力显微镜（AFM）探针的纳米机械刻蚀技术以其成本低、分辨率高的优势被广泛应用于各种纳米元器件的制造中．为了得到最优的光栅结构，首先通过单次刻蚀实验定量分析了刻蚀方向、加栽力和刻蚀速率等3个主要加工参数对所得纳米沟槽形貌和尺寸的影响，给出了普通氮化硅探针对聚碳酸酯（PC）的加工特性及加工效率．然后通过改变沟槽间距（100—500nm）得到了不同周期的纳米光栅结构，并确定了这种探针与样品的组合对间距的要求及最佳加工参数：沿垂直于微悬臂长轴向右刻蚀，加载力2．3μN，刻蚀速率2．6μm／s．最后利用该技术对实验室已有原子光刻技术所得周期为213nm的一维Cr原子光栅结构进行了复制加工。得到了均匀的213nm一维光栅，证明这种基于AFM探针的纳米机械刻蚀技术可被广泛应用于纳米加工．

The nano mechanical etching technology using an atomic force microscope （AFM） tip as a scratching tool, also known as AFM scratching, has been widely applied in nano fabrication thanks to its low cost and high resolution. To obtain better nano-grating, single scratch tests （SSTs） were carried out, before nano fabrication, using AFM scratching method. Firstly, the effects of main scratching parame- ters, including scratching direction, applied tip force and scratching speed, on the morphology and size of the scratched geometry were specifically evaluated. Then the scratehability and scratching efficiency on polycarbonate （PC） surface with a silicon nitride tip were assessed. After SSTs, nano-gratings with differ- ent periods were fabricated by changing the feed from 100 nm to 500 nm, and the comparison results in- dicate that there is a restriction to the grating period. Furthermore, the optimal scratching parameters can be obtained ： scratching along the direction perpendicular to the long axis of cantilever to the right with a load force of 2. 3 μN and a scratching speed of 2.6 μm/s. Finally, a 213 nm grating template was fabri- cated by Cr atom lithography, and 213 nm uniform grating structure was replicated with the patterning technique using an AFM silicon nitride tip as a scratching tool. The result demonstrates that the AFM scratching method can be widely used in nano fabrication.