3D High-resolution Mapping of Polarization Profiles in Thin Poly(vinylidenefluoride-trifluoroethylene) (PVDF-TrFE) Films Using Two Thermal Techniques

• Published in: IEEE transactions on dielectrics and electrical insulation Vol. 16; no. 3; pp. 676 - 681
• Main Authors: Pham, Cong-duc, Petre, Anca, Berquez, Laurent, Flores-Suarez, Rosaura, Mellinger, Axel, Wirges, Werner, Gerhard, Reimund
• Format: Journal Article
• Language: English
• Published: New York IEEE 01-06-2009; The Institute of Electrical and Electronics Engineers, Inc. (IEEE); Institute of Electrical and Electronics Engineers
• Subjects: dielectrics; Electrical insulation; Electrodes; Engineering Sciences; Extraterrestrial measurements; FLIMM; Focused laser intensity modulation method; Frequency; Intensity modulation; Mapping; Modulation; Nondestructive testing; Physics; Piezoelectric polarization; Polarization; polymers; Pulse measurements; Space charge; space charges; thermal pulse tomography; Thin films; Three dimensional; Time domain analysis; Tomography; TPT; Space charge; Polarization; Polymer; Thermal pulse tomography (TPT); Dielectric materials; FLIMM
• ISSN: 1070-9878; 1558-4135
• DOI: 10.1109/TDEI.2009.5128505

In this paper, two non-destructive thermal methods are used in order to determine, with a high degree of accuracy, three-dimensional polarization distributions in thin films (12 mum) of poly(vinylidenefluoride-trifluoroethylene) (PVDF-TrFE). The techniques are the frequency-domain Focused Laser Intensity Modulation Method (FLIMM) and time-domain Thermal-Pulse Tomography (TPT). Samples were first metalized with grid-shaped electrode and poled. 3D polarization mapping yielded profiles which reproduce the electrode-grid shape. The polarization is not uniform across the sample thickness. Significant polarization values are found only at depths beyond 0.5 mum from the sample surface. Both methods provide similar results, TPT method being faster, whereas the FLIMM technique has a better lateral resolution.