Quantitative Measurement of Cantilever Spring Constant Using Heterodyne Interferometer

摘要

Using thermal fluctuation induced oscillation, spring constant of different types of reference cantilevers have been measured by heterodyne laser interferometer with traceable displacement at a resolution of 2.6 × 10{sup}15 m/(Hz){sup}(1/2). This method provides precise measurements of the scanning probe cantilevers with spring constants ranging from mN/m to kN/m. The accuracy of the spring constant was verified by geometric calculation of the reference levers and measurement by electrostatic force balance. Factors that affect the accuracy impact of thermal tune background have been thoroughly investigated.