title: Low-voltage and high-performance buzzer-scanner based streamlined atomic force microscope system.
abstract: In this paper we present a novel scanner design in a quad-rod actuation structure, actuated by piezoelectric disk buzzers, and a new type of atomic force microscope (AFM), which uses this buzzer-scanner and a compact disk/digital-versatile-disk astigmatic optical pickup unit (OPU) for the detection of cantilever movements. Commercially available piezoelectric disk buzzers have a low capacitance and can be driven by low-voltage signal sources, such as analog outputs from a data acquisition card, without additional voltage or current amplifiers. Various scanning ranges can be realized through changing the dimensions of the actuation structure and/or the choice of disk buzzer. We constructed a buzzer-scanner and evaluated its performance. The scanner had a scanning range of 15 μm in the X and Y directions and an actuation range of 3.5 μm on the Z axis, with nonlinearity of 2.11%, 2.73%, and 2.19% for the X,Y and Z axes, respectively. The scanner had a resonance frequency of approximately 360 Hz on the X and Y axes, and 4.12 kHz on the Z axis. An OPU-AFM with this buzzer-scanner can resolve single atomic steps of a graphite substrate with a noise level of 0.06 nm. The obtained topographic images exhibit much less distortion than those obtained with an AFM using a piezoelectric tube scanner.
authors.affiliation: Institute of Physics, Academia Sinica, Taipei, 11529, Taiwan. Department of Mechanical Engineering, National Taiwan University, Taipei, 10617, Taiwan.
authors.forename: Wei-Min
authors.initials: WM
authors.lastname: Wang
authors.forename: Kuang-Yuh
authors.initials: KY
authors.lastname: Huang
authors.forename: Hsuan-Fu
authors.initials: HF
authors.lastname: Huang
authors.forename: Ing-Shouh
authors.initials: IS
authors.lastname: Hwang
authors.forename: En-Te
authors.initials: ET
authors.lastname: Hwu