title: High-speed atomic force microscope based on an astigmatic detection system.
abstract: High-speed atomic force microscopy (HS-AFM) enables visualizing dynamic behaviors of biological molecules under physiological conditions at a temporal resolution of 1s or shorter. A small cantilever with a high resonance frequency is crucial in increasing the scan speed. However, detecting mechanical resonances of small cantilevers is technically challenging. In this study, we constructed an atomic force microscope using a digital versatile disc (DVD) pickup head to detect cantilever deflections. In addition, a flexure-guided scanner and a sinusoidal scan method were implemented. In this work, we imaged a grating sample in air by using a regular cantilever and a small cantilever with a resonance frequency of 5.5 MHz. Poor tracking was seen at the scan rate of 50 line/s when a cantilever for regular AFM imaging was used. Using a small cantilever at the scan rate of 100 line/s revealed no significant degradation in the topographic images. The results indicate that a smaller cantilever can achieve a higher scan rate and superior force sensitivity. This work shows the potential for using a DVD pickup head in future HS-AFM technology.
authors.affiliation: Institute of Physics, Academia Sinica, Nankang, Taipei 11529, Taiwan.
authors.forename: H-S
authors.initials: HS
authors.lastname: Liao
authors.affiliation: Institute of Physics, Academia Sinica, Nankang, Taipei 11529, Taiwan.
authors.forename: Y-H
authors.initials: YH
authors.lastname: Chen
authors.affiliation: Institute of Physics, Academia Sinica, Nankang, Taipei 11529, Taiwan.
authors.forename: R-F
authors.initials: RF
authors.lastname: Ding
authors.affiliation: Institute of Physics, Academia Sinica, Nankang, Taipei 11529, Taiwan.
authors.forename: H-F
authors.initials: HF
authors.lastname: Huang
authors.affiliation: Institute of Physics, Academia Sinica, Nankang, Taipei 11529, Taiwan.
authors.forename: W-M
authors.initials: WM
authors.lastname: Wang
authors.affiliation: Institute of Physics, Academia Sinica, Nankang, Taipei 11529, Taiwan.
authors.forename: E-T
authors.initials: ET
authors.lastname: Hwu
authors.affiliation: Department of Mechanical Engineering, National Taiwan University, Taipei 10617, Taiwan.
authors.forename: K-Y
authors.initials: KY
authors.lastname: Huang
authors.affiliation: Institute of Physics, Academia Sinica, Nankang, Taipei 11529, Taiwan.
authors.forename: C-S
authors.initials: CS
authors.lastname: Chang
authors.affiliation: Institute of Physics, Academia Sinica, Nankang, Taipei 11529, Taiwan.
authors.forename: I-S
authors.initials: IS
authors.lastname: Hwang