基于表面形貌空间频率特征的AFM操作模式(英文)

An AFM's Operation Mode Based on Spatial Frequency Characteristics of Surface Profile

恒力模式和恒高模式是原子力显微镜的两种主要操作模式.前一种模式通常用于成像在垂直方向变化大的表面,但仅对低空间频率表面有效.后一种模式仅对光滑表面在高分辨率高扫描速度下的成像有用.为克服这些缺点,提出了组合恒高和恒力的新操作模式.使用这个模式,表面形貌的低空间频率成分利用垂直压电扫描器及其控制信号跟踪并测量,高空间频率成分利用悬臂信号测量.然后,表面形貌图像利用组合低频和高频成分得到.仿真结果证明了这种新的操作模式具有高速和高分辨率的优点.

Atomic force microscope （AFM） is operated in two principal modes, constant-force mode and constant-height mode. The former one is usually used for rougher surfaces in vertical direction but it is valid only for the low spatial fre- quency surface, while the latter one is only particularly useful for imaging smoother surfaces with high resolution and high scan speed. To overcome these shortcomings, a new operation mode combining constant-height and constant-force mode was proposed in this paper. Using the combined operation mode, the low spatial frequency component of surface profile was tracked and measured by the vertical piezoscanner and the compensating control signal; and the high spatial frequency com- ponent was measured by cantilever signal. Then the image of surface profile was acquired by combining the low-frequency and high-frequency components. Simulation results demonstrate that the combined operation mode has the advantages of high speed and high resolution.