Cantilevered bimorph-based scanner for high speed atomic force microscopy with large scanning range

Abstract

A cantilevered bimorph-based resonance-mode scanner for high speed atomic force microscope ͑AFM͒ imaging is presented. The free end of the bimorph is used for mounting a sample stage and the other one of that is fixed on the top of a conventional single tube scanner. High speed scanning is realized with the bimorph-based scanner vibrating at resonant frequency driven by a sine wave voltage applied to one piezolayer of the bimorph, while slow scanning is performed by the tube scanner. The other piezolayer provides information on vibration amplitude and phase of the bimorph itself simultaneously, which is used for real-time data processing and image calibration. By adjusting the free length of the bimorph, the line scan rate can be preset ranging from several hundred hertz to several kilohertz, which would be beneficial for the observation of samples with different properties. Combined with a home-made AFM system and a commercially available data acquisition card, AFM images of various samples have been obtained, and as an example, images of the silicon grating taken at a line rate of 1.5 kHz with the scan size of 20 m are given. By manually moving the sample of polished Al foil surface while scanning, the capability of dynamic imaging is demonstrated.

Visualization of Electrochemical Cycling-Induced Dimension Change in LiMn2O4 Nanoparticles by High-Speed Atomic Force Microscopy

“…The EC-HS-AFM setup used in this work was developed based on our previous homemade HS-AFM system. ,− To achieve high-speed imaging during electrochemical cycling, two major requirements should be satisfied. One of them was the use of a small cantilever (BioLever mini, BL-AC40TS-C2, Olympus, Japan) with a ∼25 kHz resonance frequency in an aqueous solution because this bandwidth was adequate for high-speed imaging at the rate of ∼1 frame/s in the contact mode.…”

“…In the present work, we developed an EC-HS-AFM technique by combining our previous homemade HS-AFM system ,− with cyclic voltammometry, which enabled nanoscale imaging at the rate of ∼1 frame/s during the electrochemical cycling. Spinel LiMn 2 O 4 was chosen as a cathode electrode because it is one of the promising cathode materials for the LIBs due to its high operation voltage, high energy density, low toxicity, and low cost.…”

Real-time deflection and friction force imaging by bimorph-based resonance-type high-speed scanning force microscopy in the contact mode

“…In our experimental setup, fast scan ( x -axis) was realized by using a resonance-type piezoelectric bimorph scanner [ 41 , 42 ]. Traditional piezo tube scanner provides slow scan ( y -axis) and motion in z -axis for keeping an average height to the sample surface while imaging in high speed [ 20 , 24 , 25 ].…”

Oscillatory Motions of a Cantilever in High-Speed Atomic Force Microscopy in Constant-Height Mode

“…s an important method to study the dynamic process in the nanometer scale, high-speed atomic force microscopy (AFM) has been paid considerable attention in the last decade. Great progress has been made in technical areas such as designing new cantilevers with smaller dimensions, [1][2][3] high-speed scanners, 1,2,[4][5][6][7] feedback circuit in z-direction with high bandwidth, [8][9][10] as well as measurement modes of operation. [11][12][13] It is well known that operation modes, mainly including constant-force 11) and tapping 14) ones, are important functions and have been widely used in conventional AFM for imaging.…”

“…Recently, it has been shown that AFM images can be taken at high speed in the constant-height mode, where the sample is controlled to maintain an average height by the feedback system. 5) The feedback system consists of various devices including a cantilever, a detector for sensing cantilever deflection, a feedback circuit, and a z-scanner that moves the sample stage in the z-direction. While imaging at high speed in constant-height mode, the cantilever tip is held in contact with the sample surface and the flexural deflection of the cantilever is used to measure the local height of the surface.…”