Self-Sensing and –Actuating Probes for Tapping Mode AFM Measurements of Soft Polymers at a Wide Range of Temperatures

Self-sensing and –actuating probes optimized for conventional tapping mode atomic force microscopy (AFM) are described. 32-kHz quartz tuning forks with a chemically etched and focus ion beam (FIB) sharpened (curvature radii are 5-10 nm) tungsten tip are stable at air and liquid nitrogen atmosphere and at a wide range of temperatures. If driven at constant frequency, the scan speed of such sensors can be up to 3 Hz. AFM was performed on polymer samples in order to study the stability and applicability of these sensor for investigation of soft materials with high dynamical tendencies.

一种尖锐扫描隧道显微镜针尖的制备方法

采用电化学刻蚀方法来制备针尖,然后通过提拉法得到与静态刻蚀相比更尖锐的针尖。本文研究了提拉速度对针尖形貌的影响,采用扫描电子显微镜(SEM)观察了针尖形貌。结果表明,当提拉速度过慢时,得到的针尖形貌与静态刻蚀相似,无明显优势;当提拉速度过快时导致钨丝尖端离开液面无法刻蚀;提拉速度为4μm/s时可以得到尖锐的针尖。