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Hand-in-hand with the smart-grid paradigm development, power converters used in high-power applications are facing important challenges related to efficiency and power quality. To overcome these issues, the pre-programmed Pulse-Width Modulation (PWM) methods have been extensively applied to reduce the harmonic distortion with very low power switching losses for high-power converters. Among the pre-programmed PWM techniques, Selective Harmonic Elimination (SHE) has been the prevailing solution, but recently, Selective Harmonic Mitigation (SHM) stands as a superior alternative to provide further control of the harmonic spectrum with similar losses. However, the large computational burden required by the SHM method to find a solution confines it as an off-line application, where the switching set valid solutions are pre-computed and stored in a memory. In this paper, for the first time, a real-time implementation of SHM using an off-the-shelf mid-range microcontroller is presented and tested. The Exchange Market Algorithm (EMA), initially focused on optimizing financial transactions, is considered and executed to achieve the SHM targets. The performance of the EMA-based SHM is presented showing experimental results considering a reduced number of switching angles applied to a specific three-level converter, but the method can be extrapolated to any other three-level converter topology. Ministerio de Ciencia e Innovación de España TEC2016-78430-R Junta de Andalucía P18-RT-1340 Fondo Nacional de Investigación de Qatar NPRP 9-310-2-134

Sputter deposited carbon has been tested as Reactive Ion Etching (RIE) intermediate, i.e. as second layer in a bi-layer resist system. E-beam written Hydrogen Silsesquioxane (HSQ) patterns or their reversed complementary (silicon) patterns (obtained by Chemical Mechanical Polishing (CMP)) were used as top layer. Using oxygen RIE, features smaller than 50nm wide have been transferred into the sputtered carbon in both the forwarded and the reversed tone. After oxygen RIE of the reversed bi-layer, however, extensive surface roughness is observed. Auger spectra of our sputtered carbon show predominantly sp^2 bonds, indicating that the sputter deposited material is comparable to the glassy carbon which has been used as sputter target. The etch resistance of this sputtered carbon in many standard etch recipes outperforms Novolak and Poly Hydroxy Styrene (PHS) based resists. The etch rates can be correlated to the normalized average amount of (nearest neighbour) carbon to carbon atom bonds for a carbon atom in the resist, the carbon-carbon neighbour ratio parameter C^2NR.

The Internet of Things is driving extensive efforts to develop intelligent everyday objects. This requires seamless integration of relatively simple electronics, for example through `stick-on' electronics labels. We believe the future evolution of this technology will be governed by Wright's Law, which was first proposed in 1936 and states that the cost of a product decreases with cumulative production. This implies that a generic electronic device that can be tailored for application-specific requirements during downstream integration would be a cornerstone in the development of the Internet of Things. We present an 8-bit thin-film microprocessor with a write-once, read-many (WORM) instruction generator that can be programmed after manufacture via inkjet printing. The processor combines organic p-type and soluble oxide n-type thin-film transistors in a new flavor of the familiar complementary transistor technology with the potential to be manufactured on a very thin polyimide film, enabling low-cost flexible electronics. It operates at 6.5 V and reaches clock frequencies up to 2.1 kHz. An instruction set of 16 code lines, each line providing a 9 bit instruction, is defined by means of inkjet printing of conductive silver inks. ispartof: Scientific Reports vol:4 issue:1 ispartof: location:England status: published

We present an 8b general-purpose microprocessor realized in a hybrid oxide-organic complementary thin-film technology. The n-type transistors are based on a solution-processed n-type metal-oxide semiconductor, and the p-type transistors use an organic semiconductor. As compared to previous work utilizing unipolar logic gates [1], the higher mobility n-type semiconductor and the use of complementary logic allow for a >50x speed improvement. It also adds robustness to the design, which allowed for a more complex and complete standard cell library. The microprocessor consists of two parts, a processor core chip and an instruction generator. The instructions are stored in a Write-Once-Read-Many (WORM) memory formatted by a post-fabrication inkjet printing step, called Print-Programmable Read-Only Memory (P2ROM). The entire processing was performed at temperatures compatible with plastic foil substrates, i.e., at or below 250°C [2].

We demonstrate organic imaging sensor arrays fabricated on flexible plastic foil with the solution processing route for both photodiodes and thin film transistors. We used the photovoltaic P3HT:PCBM blend for fabricating the photodiodes using spin coating and pentacene as semiconductor material for the TFTs. Photodiodes fabricated with P3HT:PCBM absorb in the green part of the visible spectrum which matches with the typical scintillator output wavelength. The arrays consist of 32x32 pixels with variation in pixel resolution of 200μmx200μm, 300μmx300μm and of 1mmx1mm. The accurate reproducibility of shadow images of the objects demonstrates the potential of these arrays for imaging purposes. We also demonstrate that the crosstalk is relatively insignificant despite the fact that the active photodiode forms a continuous layer in the array. Since both photodiodes and TFTs are made of organic material, they are processed at low temperatures below 150°C on foil which means that these imaging sensors can be flexible, light weight and low cost when compared to conventional amorphous silicon based imaging sensors on rigid substrates. In combination with a scintillator on top of the arrays, we show the potential of these arrays for the X-ray imaging applications. cop. 2014 Copyright SPIE. Organisations: Brussels Photonics Team (B-PHOT); Brussels-Capital Region; et al.; Fonds Wetenschappelijk Onderzoek (FWO); The Society of Photo-Optical Instrumentation Engineers (SPIE); Ville de Bruxelles

We describe a multiplexed TFT array for the temperature controlled thermal cycling required for DNA amplification. LTPS is an ideal technology to enable the accurate and uniform temperature profiles required for assays used in a range of medical conditions as it enables high parallelism at low cost for rapid diagnosis. We will present the application background, the design, fabrication and testing of our LTPS thermal cycler.