Title :
Ultraflexible Tactile Piezoelectric Sensor Based on Low-Temperature Polycrystalline Silicon Thin-Film Transistor Technology
Author :
Maita, Francesco ; Maiolo, Luca ; Minotti, Antonio ; Pecora, Alessandro ; Ricci, Davide ; Metta, Giorgio ; Scandurra, Graziella ; Giusi, Gino ; Ciofi, Carmine ; Fortunato, Guglielmo
Author_Institution :
Ist. per la Microelettronica e Microsistemi, Consiglio Naz. delle Ric., Rome, Italy
Abstract :
In this paper, we present an ultraflexible tactile sensor, in a piezo-eletricoxide-semiconductor FET configuration, composed by a poly[vinylidenefluoride-co-trifluoroethylene] capacitor with an embedded readout circuitry, based on nMOS polysilicon electronics, integrated directly on polyimide. The ultraflexible device is designed according to an extended gate configuration. The sensor exhibits enhanced piezoelectric properties, thanks to the optimization of the poling procedure (with electric field up to 3 MV/cm), reaching a final piezoelectric coefficient d33 of 47 pC/N. The device has been electromechanically tested by applying perpendicular forces with a minishaker. The tactile sensor, biased in a common-source arrangement, shows a linear response to increasing sinusoidal stimuli (up to 2 N) and increasing operating frequencies (up to 1200 Hz), obtaining a response up to 430 mV/N at 200 Hz for the sensor with the highest value of d33. The sensor performances were also tested after several cycles of controlled bending in different amount of humidity with the intent to investigate the device behavior in real conditions.
Keywords :
MOSFET; elemental semiconductors; piezoelectric thin films; piezoelectric transducers; piezoelectricity; readout electronics; semiconductor device testing; silicon; tactile sensors; temperature sensors; thin film capacitors; thin film sensors; thin film transistors; Si; bending; common-source arrangement; electromechanical testing; embedded readout circuitry; enhanced piezoelectric property; extended gate configuration; frequency 200 Hz; low-temperature polycrystalline silicon thin-film transistor technology; minishaker; nMOS polysilicon electronics; optimization; piezoeletricoxide-semiconductor FET configuration; poly[vinylidenefluoride-cotrifluoroethylene] capacitor; polyimide; ultraflexible tactile piezoelectric sensor; Capacitors; Electrodes; Electronic mail; Robot sensing systems; Temperature sensors; Thin film transistors; Piezoelectric-oxide-semiconductor field effect transistor (POSFET); piezoelectric-oxide-semiconductor field effect transistor (POSFET),; poly[vinylidenefluoride-co-trifluoroethylene] (PVDF-TrFE); polysilicon TFT; polysilicon TFT, poly[(vinylidenefluoride-co-trifluoroethylene] (PVDF-TrFE),; tactile sensor; ultra-flexible polyimide;
Journal_Title :
Sensors Journal, IEEE
DOI :
10.1109/JSEN.2015.2399531