We investigated the canonical ferroelectric response of a thin ferroelectric polymer film using a piezoelectric force microscopy method. The thin ferroelectric poly(vinyliden fluoride-ran-trifluoroethylene) layer with a thickness of 5 nm was prepared on a (111)Pt/TiO2/SiO2/Si substrate by a Langmuir-Blodgett method. The flip speed into upward polarization in the thin ferroelectric polymer layer is faster than that into downward polarization because the adhesion strength of the fluorine atoms in the ferroelectric polymer layer with the Pt electrode is stronger than that of the hydrogen atoms. (C) 2010 The Electrochemical Society. [DOI: 10.1149/1.3507412] All rights reserved.