Previous studies have demonstrated the use of crystalline organic semiconductors to detect and localize the passage of charged particles and energetic radiation. [1-6] In this context, polycrystalline bis-(triisopropylsilylethynyl)pentacene (TIPS-pentacene) was printed onto polyethylene naphthalate (PEN) substrates patterned with parylene-C dielectric, PEDOT electrodes and gold pads to form fully organic flexible x-ray detectors. The electrodes were patterned using orthogonal photolithography and oxygen reactive ion etching to define a width/length (W/L) = 100 µm/10 µm. An organic voltage divider built using these materials was hot bar bonded to a printed circuit board (PCB) via a flexible conducting tape to form a complete sensor system. The devices were irradiated with a variety of localized and large area sources and the output was extracted from the node between the two resistors and then connected to an operational amplifier via a second PCB. Dark currents for each resistor were in the 100 pA - 1 nA range. The device demonstrated has the potential to be applied in microdosimetry to allow for detection using a cross-section that matches organic tissue forming a solid state tissue equivalent detector (SSTED) .
 Beckerle, P. and Ströbele, H., 2000. Charged particle detection in organic semiconductors. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 449(1-2), pp.302-310.
 Fraboni, B., Ciavatti, A., Merlo, F., Pasquini, L., Cavallini, A., Quaranta, A., Bonfiglio, A. and Fraleoni‐Morgera, A., 2012. Organic Semiconducting Single Crystals as Next Generation of Low‐Cost, Room‐Temperature Electrical X‐ray  Detectors. Advanced Materials, 24(17), pp.2289-2293.
Intaniwet, A., Keddie, J.L., Shkunov, M. and Sellin, P.J., 2011. High charge-carrier mobilities in blends of poly (triarylamine) and TIPS-pentacene leading to better performing X-ray sensors. Organic Electronics, 12(11), pp.1903-1908.
 Kane, M.C., Lascola, R.J. and Clark, E.A., 2010. Investigation on the effects of beta and gamma irradiation on conducting polymers for sensor applications. Radiation Physics and Chemistry, 79(12), pp.1189-1195..
 Lai, S., Cosseddu, P., Basiricò, L., Ciavatti, A., Fraboni, B. and Bonfiglio, A., 2017. A Highly Sensitive, Direct X‐Ray Detector Based on a Low‐Voltage Organic Field‐Effect Transistor. Advanced Electronic Materials, 3(8), p.1600409.
 Schrote, K. and Frey, M.W., 2013. Effect of irradiation on poly (3, 4-ethylenedioxythiophene): poly (styrenesulfonate) nanofiber conductivity. Polymer, 54(2), pp.737-742.
 Bardash, M., 2010, August. An organic semiconductor device for detecting ionizing radiation on a cellular level. In Organic Semiconductors in Sensors and Bioelectronics III (Vol. 7779, p. 77790F). International Society for Optics and Photonics.
In the past few years, with the advance of laser technology, laser engraving has been considered as an alternative method to traditional lithography in the fabrication of microfluidic devices. Considering solution-based method as the main technique for perovskite deposition, the capillary motion of perovskite precursor can be employed for filling a laser-engraved patterned conducting layer. Herein, we used CO2 laser micromachining for the fabrication of the perovskite photodetector. First, several microchannels were formed by laser engraving of indium tin oxide (ITO) coated polyethylene terephthalate (PET) substrates. Power, speed and frequency parameters of the laser were varied in order to achieve the desired channel roughness. The samples were characterized by scanning electron microscope (SEM) and potentiostat. The I-V characteristics and bode plots of the sample showed a capacitive and an inductive behavior. Finally, a simulation tool was used to analyze the experimental data. This approach offers a simple, rapid and low-cost fabrication method for perovskite photodetector and can be used in large-scale commercial application.
We have developed a system of flexible optical imaging bands that can be used to assess the effects of systemic lupus erythematosus (SLE) on finger joints. Each imaging band consists of four pairs of light sources and a photodetector. The light sources contain three different light emitting diodes with wavelengths of 530 nm, 655 nm and 940 nm. Two of these imaging bands are wrapped around the proximal interphalangeal (PIP) joints of the index-, middle-, and ringfingers. The imaging bands gather transmitted and reflected light intensities from the tissues for ~ 4 minutes including two venous occlusions. This results in hemodynamic time traces for all source-detector pairs. From theses traces a rise, plateau, and fall time are calculated. We found that, on average, signals obtained from SLE patients displayed a shorter rise time and longer plateau time as compared to signals from healthy controls. Performing a two-dimensional linear discriminant analysis on the rise and plateau times, we obtained the best specificity of 89% and the best sensitivity of 76 %. Area under the receiver operating characteristic (ROC) curve is 0.86.
Nanophotonic structures including photonic crystals and plasmonics have a lot of potential applications in spectral sensing. These devices typically require electron beam lithography, a slow process, for fabrication. Successful
commercialization of these technologies requires reproducible, high volume fabrication. Projection lithography
is an established process for rapid, reproducible patterning. We have successfully pushed the limits of projection
lithography to develop a low-cost, high-throughput alternative to electron beam lithography for our nanoscale,
visible-wavelength photonic crystal spectral sensors. The developed process is 100 times faster than electron
beam lithography for 10mm by 10mm dies on a four inch wafer. Testing of the photonic crystals in spectral
sensors shows uniformity in large scale production which is robust to defects from processing.
For the development of the next generation lithium-ion batteries it is primordial to investigate new materials as potential candidates towards the increase of the specific capacity of the anode and the new lighter and efficient cells. In this paper we present our investigation on amorphous silicon (a-Si) deposited by DC-sputtering on top of Single Layer Graphene (SLG) grown by Chemical Vapor Deposition (CVD). Our aim being to improve the mechanical properties of the silicon volume change during charging and discharging cycles, it is found that half cells fabricated with such electrodes can achieve specific capacity values above 2000 mAh/g while avoiding large pulverization phenomena. However, it is also found that the a-Si/SLG interface results in high resistance electrodes and decreases cell performance. We suggest that by improving the a-Si/SLG contact resistance, the performance will further improve.
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