Effects of nanometric plastic strain on the cantilever deflection sensitivity calibration accuracy for atomic force microscopy (AFM)-nanoindentation tests

Abstract

Cantilever deflection sensitivity ((Formula presented.)) calibration is a critical issue for a correct transduction of the electric signal into mechanical one in atomic force microscopy (AFM)-nanoindentation. Indenter-induced strains in calibration samples can negatively impact on the (Formula presented.) calibration reliability, becoming more important as the cantilever deflection ((Formula presented.)) set for this calibration process is increased. In this work, we present a systematic study regarding the (Formula presented.) setpoint effects on the (Formula presented.) value calibration. (Formula presented.) setpoints between 0.05 and 1 [V] were considered for measurements, observing a clear decreasing trend in the (Formula presented.) value for (Formula presented.) 0.125 [V] concerning the most accurate value (Formula presented.) 192 [nm/V]. The results demonstrate that underestimations up to 10% concerning this value may be obtained by choosing non-adequate (Formula presented.) setpoints. This study shows the relevance of the (Formula presented.) setpoint for accurate (Formula presented.) calibration, which is essential for reliable quantitative studies of mechanical properties.