High-speed atomic force microscopy for large scan sizes using small cantilevers

Abstract

We present a high-speed atomic force microscope that exhibits a number of practical advantages over previous designs. Its central component is a high-speed scanner with a maximum scan size of 23 microm x 23 microm and a conveniently large sample stage area (6.5 mm x 6.5 mm). In combination with small cantilevers, image rates of up to 46 images s(-1) in air and 13 images s(-1) in liquid are reached under z-feedback control. By large scan size imaging of collagen fibrils in air, sample velocities of 8.8 mm s(-1) in the xy-direction and 11 mm s(-1) in the z-direction are reached. To provide optimized imaging conditions for both large and small scan sizes, a modular scanner design allows easily exchanging the x- and y-piezos. The scanner is therefore also suited for investigations on the molecular and atomic scale, which is demonstrated by imaging the step dynamics of a calcite surface during dissolution and the hexagonal lattice of a mica surface in liquid.

Method of mechanical holding of cantilever chip for tip-scan high-speed atomic force microscope

“…This vibration generation can be easily be suppressed by the scan speed being lowered only in the precipitous downward regime, as described previously. 17 The time delay added by this slower scan is negligible because it is much shorter than the frame imaging time.…”

“…These observations have provided greater insights than ever before into how the proteins function, thus demonstrating the innovative power of this microscopy. Recently, fast widearea scanners displaceable up to 23 × 23 µm 2 or up to ∼50 × 50 µm 2 have been developed 17,18 together with a new vibration damping method for the wide-area scanners, 18 expanding the objects of HS-AFM observation to much larger ones. For example, various dynamic processes occurring in live bacterial and mammalian cells, such as endocytosis, membrane raffling, filopodia growth and bacteriolysis, were visualized within a few seconds.…”

Separate-type scanner and wideband high-voltage amplifier for atomic-resolution and high-speed atomic force microscopy

“…For the XY scanner [ Fig. 1(a)], we used a flexure stage with four-fold symmetry, which is similar to the design reported by Hansma et al [9][10][11][12][13] The main body is made of stainless steel (SS304 or SS430). The sample stage at the center is connected to the four sides by three beams for each.…”

“…[9][10][11] Subsequently, the design has been further improved by other researchers. 12, 13 Tabak et al developed a micrometer-sized Z scanner with an integrated tip for obtaining a high resonance frequency. 14 They also used an XY sample scanner that is separated from the Z scanner to achieve low cross talk.…”

High-speed dynamic atomic force microscopy by using a Q-controlled cantilever eigenmode as an actuator

“…To increase the imaging bandwidth, both the sensor and the actuator sizes have been minimized at the expense of increased system complexity [7][8][9][10][11][12][13]. Fast X-Y scanners have been developed [14][15][16][17][18]. Novel probe structures with integrated actuators were also designed [19][20][21][22][23][24][25].…”