Atomic force microscope (AFM) tip-based nanomilling is an emerging technology for machining nanostructures with a high rate of material removal and slight tip wear. However, subsurface damage induced by nanomilling is poorly understood. In this study, we investigated nanomilling-induced subsurface damage of single-crystal silicon experimentally and with molecular dynamics simulations. We studied the effect of clockwise and anticlockwise trajectories on the nanochannel morphology. The clockwise trajectory resulted in a ‘U’-shaped nanochannel at a relatively low normal load. Transmission electron microscopy and Raman spectroscopy analysis of the nanochannel subsurface revealed atomic-scale defects, including dislocations, stacking faults, and amorphous silicon. Molecular dynamics simulations described the evolution of the phase transformation and subsurface damage. This work reveals the mechanism of subsurface damage of single-crystal silicon in nanomilling, which will facilitate the machining of nanostructures with minimal subsurface damage.

基于原子力显微镜 (AFM) 尖端的纳米铣削是一种新兴技术，用于加工具有高材料去除率和轻微尖端磨损的纳米结构。然而，对纳米铣削引起的亚表面损伤知之甚少。在这项研究中，我们通过实验和分子动力学模拟研究了纳米铣削引起的单晶硅的亚表面损伤。我们研究了顺时针和逆时针轨迹对纳米通道形态的影响。顺时针轨迹在相对较低的法向载荷下产生“U”形纳米通道。纳米通道次表面的透射电子显微镜和拉曼光谱分析揭示了原子级缺陷，包括位错、堆垛层错和非晶硅。分子动力学模拟描述了相变和地下损伤的演变。这项工作揭示了纳米铣削中单晶硅的亚表面损伤机制，这将有助于以最小的亚表面损伤加工纳米结构。