Characterization of AFM tip parameters with typical Si (100) microstructures

Typical Microelectromechanical System (MEMS) trapezoidal microstructures with intrinsic sidewall angle (54.73°) are fabricated by anisotropic chemical wet etching of silicon (100) technique. The typical MEMS structures are used as linewidth test specimens. A comparative study is presented between atomic force microscopy (AFM) and scanning electron microscope (SEM) in linewidth and profile measurement on the test microstructures. The interaction between AFM tip and specimens is analyzed when AFM tip moves one the specimens. A geometry-based dynamic model is presented to realize the accurate characterization of AFM tip shape and position status in linewidth and profile measurement. Four parameters (curvature radius, installation angle, scanning tilting angle and half-cone angle) are used to characterize AFM tip. This method improves the existing AFM tip characterization methods.