Suchergebnisse

A generation of piezoresistive sensors (force or deformation) fully processed by printing technologies is increasingly being implemented in applications due to advantages as a large-area application, simple device, integration, and high flexibility. This work reports the development of a fully printed piezoresistive (5 × 5 sensor) matrix in which an organic thin-film transistor (OTFT) is placed in each sensor to allow the readout of each sensor independently and thus reducing the crosstalk between individual sensors. The manufacturing was carried out using inkjet printing for the deposition of materials in a thin layer stacked on top of each other to obtain functional OTFTs. The piezoresistive nanocomposite sensors, based on multiwalled carbon nanotubes within an elastomeric styrene-ethylene-butadiene-styrene (SEBS) polymer matrix, were fabricated by screen printing. The fabrication and characterization of both OTFT and sensors are presented and discussed in detail. The inkjet-printed OTFTs (width/length channel ratio of ∼130) show a drain-source current (IDS) of 150 μA with a gate-source voltage of −40 V. Gauge factors of up to 5.9 were obtained for the sensors, resulting in a current variation of 1.5 μA. This corresponds to about 0.7% of the total IDS in a deformation cycle ; FCT – Fundação para a Ciência e Tecnologia within the Project Scope: UID/CEC/00319/2019, UID/FIS/04650/2019 and projects PTDC/FIS-MAC/28157/2017 and PTDC/BTM-MAT/28237/2017, SFRH/BPD/110914/2015 (PC). V.C. thanks FCT for the junior researcher contract (DL57/2016). We acknowledge funding from the European Union's Horizon 2020 Programme for Research, ICT-02-2018 - Flexible and Wearable Electronics. Grant agreement no. 824339 – WEARPLEX. Financial support from the Basque Government Industry and Education Department under the ELKARTEK, HAZITEK and PIBA ...

Organic photodetectors (PDs) based on printing technologies will allow to expand the current field of PD applications toward large-area and flexible applications in areas such as medical imaging, security, and quality control, among others. Inkjet printing is a powerful digital tool for the deposition of smart and functional materials on various substrates, allowing the development of electronic devices such as PDs on various substrates. In this work, inkjet-printed PD arrays, based on the organic thin-film transistor architecture, have been developed and applied for the indirect detection of X-ray radiation using a scintillator ink as an X-ray absorber. The >90% increase of the photocurrent of the PDs under X-ray radiation, from about 53 nA without the scintillator film to about 102 nA with the scintillator located on top of the PD, proves the suitability of the developed printed device for X-ray detection applications ; The authors thank FEDER funds through the COMPETE 2020 Programme and National Funds through FCT-Portuguese Foundation for Science and Technology under Strategic Funding UID/FIS/04650/2013 and projects PTDC/EEI-SII/5582/2014, PTDC/CTM-ENE/5387/2014 and in the framework of EuroNanoMed 2016 call, Project LungChek ENMed/0049/2016. J.O. and V.C. thank the FCT for the SFRH/BD/98219/2013 and SFRH/BPD/97739/2013 grants, respectively. The authors acknowledge funding by the Spanish Ministry of Economy and Competitiveness (MINECO) through the project MAT2016-76039-C4-3-R. Financial support from the Basque Government Industry Department under the ELKARTEK program is also acknowledged. The authors thank Iain McCulloch and Martin Heeney from Flexink for providing the OSC. Dirk Rittrich (Department Layer Deposition at Fraunhofer ENAS) is acknowledged for the FIB/SEM analysis and the sample preparation. R.D.R acknowledges the DFG Unit FOR1317 SMINT, the Cluster of Excellence, and the Tomsk Polytechnic University Competitiveness Enhancement Program grant TPU CEP_IHTP_73\2017. This work was performed in the ...