Accurate measurement of the out-of-plane motion of a tip-scanning atomic force microscope

Abstract

A tip-scanning atomic force microscope (AFM) can be used as a highly accurate height-measuring instrument for large samples, such as liquid crystal displays. To accurately measure the flatness or surface roughness of large samples, the xy-scanner-induced out-of-plane motion must be known to discriminate scanner artifacts from the measured AFM images. As the topographic signals of AFM measurements contain the hysteresis of the z-scanner piezoelectric actuators, actual movements of the z-scanner were measured using a z-axis sensor glued to the actuator. The actual out-of-plane motion of the xy-scanner was found to be less than 1 nm for a 50-μm scan.

Algorithms for using silicon steps for scanning probe microscope evaluation

“…Tip shape and instrument settings such as scan speed and feedback gain will also influence the measured surface profile unevenly around the edge. The guiding system and distance sensors in both state-of-the-art commercial AFMs and tailor-made metrological atomic force microscopes (MAFMs) implemented at a few national metrological institutes are influenced by thermal drift and other nonlinear errors [19,20] indicated as δz e (x) in figure 1(b). Using the fit of two straight parallel lines near the same edge will lead to a step height different from the spacing between the lattice planes.…”

Piezoelectric actuators for the correction of optical ray path in the operation of laser gyros

“…[7][8][9][10][11] Additionally, control scheme and experimental behavior analysis of piezoelectricactuator can be considered to apply and operate the piezoelectricactuator properly. 12,13 This paper presents a practical mathematical model of a piezoelectric actuator used in the laser gyros. The piezoelectric actuator can be described in terms of geometric dimensions and structural stiffness.…”

Manipulation of nano devices with optical tweezers

“…2,3 Optical tweezers has the ability to control forces up to a few hundreds pico-newtons (pN) with sub-pN resolution on particles whose sizes varies from microns up to the nano range. 5,6 There have been many studies that have tried to trap and manipulate multiple particles simultaneously with various types of optical tweezers and methods. One of the methods introduced used a 2D/3D arrangement of micro spheres and fabrication of the rhombus structure through the cutting and fusing of nanowires with HOT (Holograph Optical Tweezers).…”