Broadband nanodielectric spectroscopy by means of amplitude modulation electrostatic force microscopy (AM-EFM)

Gustavo Ariel Schwartz (1) , Clément Riedel (2, 3) , Richard Arinero (2, 3) , Philippe Tordjeman (4) , Angel Alegría (1, 5) , Juan Colmenero (1, 6, 5)

1 CFM - Centro de Fisica de Materiales
2 IES - Institut d’Electronique et des Systèmes
3 NANOMIR - Composants à Nanostructure pour le moyen infrarouge
4 IMFT - Institut de mécanique des fluides de Toulouse
5 UPV/EHU - Universidad del Pais Vasco / Euskal Herriko Unibertsitatea [Espagne]
6 Donostia International Physics Center - DIPC (SPAIN)

In this work we present a new AFM based approach to measure the local dielectric response of polymer films at the nanoscale by means of Amplitude Modulation Electrostatic Force Microscopy (AM-EFM). The proposed experimental method is based on the measurement of the tip-sample force via the detection of the second harmonic component of the photosensor signal by means of a lock-in amplifier. This approach allows reaching unprecedented broad frequency range (2-3×104 Hz) without restrictions on the sample environment. The method was tested on different poly(vinyl acetate) (PVAc) films at several temperatures. Simple analytical models for describing the electric tip-sample interaction semi-quantitatively account for the dependence of the measured local dielectric response on samples with different thicknesses and at several tip-sample distances.

Mots clés: Nanodieklectrique; Amplitude modulation AFM; Dielectric spectroscopy; Polymers; Thin films; Heterogeneous materials

Domaines: Matériaux

Gustavo Ariel Schwartz, Clément Riedel, Richard Arinero, Philippe Tordjeman, Angel Alegría, et al.. Broadband nanodielectric spectroscopy by means of amplitude modulation electrostatic force microscopy (AM-EFM). Ultramicroscopy, 2011, vol. 111, pp. 1366-1369. ⟨10.1016/j.ultramic.2011.05.001⟩. ⟨hal-00933984⟩