Spring constant calibration of atomic force microscopy cantilevers with a piezosensor transfer standard

Journal Article · Sat Sep 15 04:00:00 EDT 2007 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.2785413· OSTI ID:21024285

Langlois, E D; Shaw, G A; Kramar, J A; Pratt, J R; Hurley, D C ^[1]

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1. Materials Science and Engineering Laboratory, National Institute of Standards and Technology, Boulder, Colorado 80305, USA and Department of Mechanical Engineering, University of Colorado, Boulder, Colorado 80309 (United States)

We describe a method to calibrate the spring constants of cantilevers for atomic force microscopy (AFM). The method makes use of a ''piezosensor'' composed of a piezoresistive cantilever and accompanying electronics. The piezosensor was calibrated before use with an absolute force standard, the NIST electrostatic force balance (EFB). In this way, the piezosensor acts as a force transfer standard traceable to the International System of Units. Seven single-crystal silicon cantilevers with rectangular geometries and nominal spring constants from 0.2 to 40 N/m were measured with the piezosensor method. The values obtained for the spring constant were compared to measurements by four other techniques: the thermal noise method, the Sader method, force loading by a calibrated nanoindentation load cell, and direct calibration by force loading with the EFB. Results from different methods for the same cantilever were generally in agreement, but differed by up to 300% from nominal values. When used properly, the piezosensor approach provides spring-constant values that are accurate to {+-}10% or better. Methods such as this will improve the ability to extract quantitative information from AFM methods.

• OSTI ID: 21024285
• Journal Information: Review of Scientific Instruments, Journal Name: Review of Scientific Instruments Journal Issue: 9 Vol. 78; ISSN 0034-6748; ISSN RSINAK
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
ATOMIC FORCE MICROSCOPY
CALIBRATION
GEOMETRY
INFORMATION
MONOCRYSTALS
NOISE
PIEZOELECTRICITY
SILICON
SPRINGS
STABILITY
STANDARDS