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ABSTRACT Fully mass printed, flexible and truly polymeric organic field effect transistors consisting of a three layer dielectric made of CYTOP (low-k), PVA (intermediate) and P(VDF-TrFE-CTFE)(high-k) are introduced. Gravure-, flexo-and screen printing were selected as highly productive manufacturing technologies. These OFETs work at strongly reduced voltages and show high field effect mobility (µ = 0.2 cm2/Vs) and remarkable good bias stress stability at very high current density (50 µA/mm). Fully printed OFETs are used for the realization of ring oscillators working in the kHz regime at reduced supply voltage (10 V). In combination with printed fully polymeric piezoelectric loudspeakers, this work shows for the first time fully printed flexible audio systems. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015, 53, 1409-1415 [ABSTRACT FROM AUTHOR]

A novel fully printed 28-bits capacity chipless RFID tag using conical resonators is proposed here. The angle of aperture of these resonators is adjusted to suppress high order modes allowing an efficient use of the UWB frequency bandwidth. By using 12 resonators within a reduced dimension of 4.2x3 cm², a coding capacity of 28 bits is achieved, which is the highest coding capacity reported for a fully printed chipless tag. Several chipless tags are printed on flexible substrate and validated experimentally. [ABSTRACT FROM AUTHOR]

All-polymer, semi-transparent, three-layer-dielectric (3L) organic field effect transistors (OFETs) are fabricated on polyethylene terephthalate plastic substrate, using high-throughput printing techniques. Analog small-signal characteristics of the 3L OFET are presented and are compared against the previous version of this technology, which was based on a single-layer dielectric and a metal gate electrode. The 3L transistor withstands 50 V, can continuously drive 50 μA/mm, reaches an excellent intrinsic-gain ( A v0 ) of 43 dB, an equivalent mobility of 0.85 cm 2 /V, and a transit frequency ( f T ) of 68 kHz, well suited for applications such as driving printed piezoelectric loudspeakers and flexible audio systems. The effects of the relaxor-ferroelectric high-k layer in the 3L stack on the gate capacitance, g m , and A v0 are measured in the frequency domain. In addition, it is observed that PEDOT:PSS makes a better interface with polymer dielectric comparing to copper particle ink. Five-hour small- and large-signal bias stress tests are performed. A novel direct A v0 measurement technique, and an improved transconductance extraction method are also presented. [ABSTRACT FROM AUTHOR]