基于针尖和样品之间的各种相互作用力,原子力显微镜(AFM)可用于样品表面形貌、摩擦力等各种物理特性的研究,它是纳米科技研究中一个重要工具.影响AFM测量图像质量的因素很多,如振幅参数、积分增益I、比例增益P、衰减增益和扫描速度等,而探针同样是提高样品表面形貌像成像质量的关键.通过采用控制变量法,并以均方根粗糙度Rq作为评判标准,用不同参数的探针测量同一样品.实验结果表明,探针的共振频率f、弹性系数k、曲率半径Rh等对测量样品粗糙度均有较大影响,可选择合适的探针,提高成像质量.同时,针对仪器使用中出现的一些常见现象及故障,作出了解释和解答.
The atomic force microscope(AFM) is based on the various forces between tips and samples,it can be used to investigate the various physical properties,such as the sample surface morphology,friction force,etc,and it is a very important tool in nanotechnology research.There are some factors can affect the quality of the surface topography image,such as amplitude reference,integral gain,proportion gain,attenuation gain,speed gain,and the proper probe is also another key point.In this paper,the control variable method is introduced in changing the different probes,and the RMS (root mean square) roughness is served as a criterion.The effect of different probes on the same sample image is studied and summarized.The results show that probe' s resonant frequency,elastic coefficient and radius of curvature have a significant impact to the sample surface roughness.The image quality can be improved by choosing the suitable probes.At the same time,we explain some problems which we have met in the application of AFM.