In this work we present a flexible pyroelectric capacitive sensor, based on PVDF-TrFE, fabricated on a ultra-thin polyimide film (8 μm thick) connected to a fully printed p-channel organic thin film transistor that is used to amplify the sensor signal. We fabricate a standalone device, exploiting a multi-foil approach, where the pyroelectric capacitor was glued on the organic TFT substrate, that consists of a PEN foil 125 μm thick, previously made in CEA-LITEN labs. The pyroelectric properties of the PVDF-TrFE capacitor were enhanced using a thermal poling procedure before the TFT integration. The sensor behavior was analyzed at different working frequencies (up to 500 Hz) under a specific infrared (IR) radiation provided by a He-Ne laser, with a wavelength of 632 nm and maximum power of 5 mW. An output signal of few millivolts was observed, exploiting the pre-amplification of the fully printed organic transistor.
1 Jan 2012
Volume: 47 Pages: 526-529