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.

Download full-text

Full-text

Available from: Martin Zirkl
    • "In this paper, we describe the design, fabrication and characterization of transparent large-area sensors for light-point localization based on only two functional polymers. Most large-area sensors are based on active or passive matrix technologies for position-sensitivity1234567891011, and only few sensor concepts avoid the division of sensor surfaces into a large number of individual sensing elements12131415161718. We used the concept of matrix-free large-area sensors to develop transparent, flexible, thin sensor surfaces for light-point localization. "
    [Show abstract] [Hide abstract]
    ABSTRACT: We present light-point localization by transparent, flexible, thin sensor surfaces based on only two functional polymers: a thin film of pyroelectric poly(vinylidene fluoride) (PVDF) combined with large-area polymer electrodes made of poly(3,4-ethylene dioxythiophene):poly(styrene sulfonic acid) (PEDOT:PSS). One of the electrodes is resistive to enable position sensitivity, and both materials are highly flexible and transparent across the visible range of light. We fabricated a one-dimensional sensor strip of 3.5 × 0.8 cm size and a two-dimensional 3 × 3 cm sensor surface. Both devices used a 25 μm thin PVDF film whose surface was activated by low-energy argon plasma. PEDOT:PSS electrodes were deposited by spin coating onto the PVDF film. The fabricated devices were validated by applying the intensity-modulated light of a red laser diode to the sensor surfaces. Our design enables position sensitivity without the need for active or passive matrix technology or external power supply, and with electronic circuitry placed only at the edges. This allows simple fabrication techniques to be employed, such as roll-to-roll-processing, spin coating and screen printing. Since low-cost polymeric materials can be used, the proposed sensors have a wealth of possible applications in consumer goods.
    No preview · Article · Jan 2016 · Sensors and Actuators A Physical
  • Source
    • "These large-area sensors offer desirable attributes such as flexibility or even stretchability reacting to pressure, touch, temperature changes, incident light or even multiple stimuli. A few sensor concepts offer alternatives to the widespread active matrix technology [2] [3] [4] [5] [6] to locate the stimulus * Corresponding author. Tel.: +43 732 2468 6260; fax: +43 732 2468 6252. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Functional materials such as piezoelectric and pyroelectric polymers or organic photodiodes are promising candidates for flexible sensor surfaces; combining thin films of these materials with large-area resistive electrodes leads to position-sensitivity for passive touch- or light-point localization, respectively. However, this type of large-area sensors for passive stimulus-localization lacks a general theoretical description, which is necessary to understand the physics underlying the sensor concept.To this end we present a one-dimensional, theoretical model for these sensors; the model is based on the solutions of the telegrapher’s equations under the appropriate boundary conditions. We specify the applied boundary conditions, list approximate solutions for certain parameter ranges and present two model-based normalization procedures. These normalization procedures allow for stimulus localization independently of its magnitude and significantly increase the quality of the measurement signals. Experimental results agree well with theoretical findings, proving the suitability of the presented theoretical models.
    Full-text · Article · Feb 2013 · Sensors and Actuators A Physical
  • Source
    • "The base polymers for the waveguides in [9] [10] [11] comply well with the requirements of low cost and simple fabrication technologies in macroelectronics. The pyroelectric properties of another polymer, namely poly(vinylidene fluoride) (PVDF), are for example used for an active matrix sensor network in a touchless control interface [4] [6]. PVDF in the E-phase is a ferroelectric polymer with pyroelectric and piezoelectric coefficients of p 3 | -25 PC/(m 2 K) and d 33 | 20 pC/N, which compare well to those of the more familiar inorganic ferroelectrics [12] [13] [14]. "
    [Show abstract] [Hide abstract]
    ABSTRACT: We present a flexible polymer sensor for light point localization based on the pyroelectric polymer poly(vinylidene fluoride) (PVDF) in combination with large area resistive electrodes. This large area sensor is simple in design; a division of the sensor surface into an array of individual sensor elements as used in active matrix technology is avoided. Electronic circuitry is placed only at the edges of the device. We have fabricated a flexible sensor strip with a length of 12 cm and a width of 1.6 cm according to the proposed concept. The position sensitive output signals of the sensor strip have been measured in response to the intensity-modulated light of a red laser diode. Two model-based normalization procedures have been developed in order to increase the quality of the measurement signals. The results indicate that the sensor strip can be treated mathematically analogous to a transmission line. Calculations based on the solutions of the telegrapher's equations under the appropriate boundary conditions are in good agreement with the experimental results, proving the suitability of the proposed concept for position sensitive detection.
    Full-text · Conference Paper · Sep 2012
Show more