Experimental determination of scanning probe microscope cantilever spring constants utilizing a nanoindentation apparatus

Abstract

A rapid, nondestructive, and accurate method for determining the normal spring constants of scanning probe microscopy cantilevers is presented. Spring constants are determined using a commercial combination atomic force microscope and nanoindentation apparatus configured with a W-indenter tip geometrically configured into either a scanning tunneling microscope pointed tip or chisel shape that may be placed onto the cantilever of interest with high accuracy. A load is applied to the cantilever tip and the corresponding displacement is measured. From the force–displacement curve, the spring constant is determined. For cantilevers with spring constants greater than 1 N/m, the derived spring constants are believed to be accurate to within ±10%, with better accuracy for stiffer levers. This method has been used to measure the stiffness of cantilevers from several manufacturers.

Force measurements with the atomic force microscope: Technique, interpretation and applications

“…The acoustic wave causes a known force on the cantilever. Holbery et al [93] use a commercial nanoindenter to measure spring constants of relatively stiff cantilevers. For cantilevers with spring constants above 1 N/m they report an error of less than 10%.…”

Lateral force calibration of an atomic force microscope with a diamagnetic levitation spring system

“…The current state of the art technique provides approximately 10% accuracy in measuring the normal force constant with a direct method of calibration. 16 The direct method usually employs another lever of known spring constant or a microfabricated array of reference springs ͑MARS͒ for the calibration. 16 In this article, a novel in situ direct method is developed to independently calibrate the lateral force constant.…”

“…16 The direct method usually employs another lever of known spring constant or a microfabricated array of reference springs ͑MARS͒ for the calibration. 16 In this article, a novel in situ direct method is developed to independently calibrate the lateral force constant. It correlates the output voltage signals from a PSPD directly to the lateral force applied on the AFM cantilever assembly by a diamagnetic levitation spring system.…”

A method for atomic force microscopy cantilever stiffness calibration under heavy fluid loading

“…[1][2][3][4][5][6][7][8][9][10] Some calibration techniques are cumbersome, involving procedures that are comparable in complexity to the experiments that require the calibrated cantilevers. 1,5,11,12 Other techniques require only the measurement of the thermally driven, random vibration of a cantilever and perhaps knowledge of a few of the parameters characterizing the cantilever and its fluid environment. 2,13,14 The majority of the exploration into cantilever calibration techniques has been validated through the comparison of one technique to another.…”