Conference Paper

Fully printable, flexible, large area organic optothermal sensors for human-machine-interfaces

DOI: 10.1109/ICSENS.2009.5398503 Conference: Sensors, 2009 IEEE
Source: IEEE Xplore

ABSTRACT Pyroelectric sensors presented in this work are based on polymers from the PVDF family which are comprised of a piezo- and/or pyroelectric polymer thin film capacitor, integrated with high performance organic thin film transistors operating at low voltages and acting as impedance converters, signal amplifiers and conditioners. For flexible integration with diverse electronic devices, large area processes applicable for industrial partners such as screen printing have been used for the fabrication of the sensors. With respect to the intended purpose for detection of human body radiation the absorbance of the impinging IR-light is dramatically increased by the application of printed carbon top electrodes, hence meeting the requirements for low-cost large area processability. Here we present good working integrated sensor devices based on two components, being an organic thin film transistor with a high-k-nanocomposite gate dielectric and a PVDF- copolymer based sensor. Besides, the integration of printed electrochemical transistors with printed sensors for large area applications has been realized successfully.

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    ABSTRACT: The fabrication method and the pyroelectric response of a single element infrared sensor based lead zirconate titanate (PZT) particles and polyvinylidene fluoride P(VDF-TrFE) copolymer composite thick film is reported in this paper. A special thermal insulation structure, including polyimide (PI) thermal insulation layer and thermal insulation tanks, was used in this device. The thermal insulation tanks were fabricated by laser micro-etching technique. Voltage responsivity (RV), noise voltage (Vnoise), noise equivalent power (NEP), and detectivity (D∗) of the PZT/P(VDF-TrFE) based infrared sensor are 1.2×103V/W, 1.25×10-6VHz1/2, 1.1×10-9W and 1.9×108cmHz1/2W-1 at 137.3 Hz modulation frequency, respectively. The thermal time constant of the infrared sensor τT was about 15ms. The results demonstrate that the composite infrared sensor show a high detectivity at high chopper frequency, which is an essential advantage in infrared detectors and some other devices.
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May 26, 2014