Reverse Offset Printing of Semidried Metal Acetylacetonate Layers and Its Application to a Solution-Processed IGZO TFT Fabrication.

The submicrometer resolution printing of various metal acetylacetonate complex inks including Fe, V, Mn, Co, Ni, Zn, Zr, Mo, and In was enabled by a robust ink formulation scheme which adopted a ternary solvent system where solubility, surface wettability, and drying as well as absorption behavior on a polydimethylsiloxane sheet were optimized. Hydrogen plasma in heated conditions resulted in bombarded, resistive, or conductive state depending on the temperature and the metal species. With a conductivity-bestowed layer of MoO and a plasma-protecting layer of ZrO situated on the top of an IGZO layer, a solution-processed TFT exhibiting an average mobility of 0.

Far-UV Annealed Inkjet-Printed InO Semiconductor Layers for Thin-Film Transistors on a Flexible Polyethylene Naphthalate Substrate.

The inkjet-printing process of precursor solutions containing In nitrate dissolved in 2-methoxyethanol is optimized using ethylene glycol as a cosolvent that allows the stabilization of the droplet formation, leading to a robust, repeatable printing process. The inkjet-printed precursor films are then converted to InO semiconductors at flexible-substrate-compatible low temperatures (150-200 °C) using combined far-ultraviolet (FUV) exposure at ∼160 nm and thermal treatment. The compositional nature of the precursor-to-metal oxide conversion is studied using grazing incidence X-ray diffraction (GIXRD), X-ray reflectivity (XRR), and Fourier transform infrared (FTIR) spectroscopy that indicate that amorphous, high density (up to 5.

Flexography-Printed In2 O3 Semiconductor Layers for High-Mobility Thin-Film Transistors on Flexible Plastic Substrate.

Industrially scalable and roll-to-roll-compatible fabrication methods are utilized to fabricate high-mobility (≈8 cm(2) V(-1) s(-1) ) nanocrystalline In2 O3 thin-film transistors (TFTs) on an flexible plastic substrate. Flexographic printing of multiple thin In2 O3 semiconductor layers from precursor-solution is performed on a Al2 O3 gate dielectric obtained via atomic layer deposition. A low-temperature post-contact-annealing step allows control of the TFT device turn-on voltage to ≈0 V for enhancement-mode operation.

Roll-to-roll printed resistive WORM memory on a flexible substrate.

The fabrication process and the operation characteristics of a fully roll-to-roll printed resistive write-once-read-many memory on a flexible substrate are presented. The low-voltage (<10 V) write operation of the memories from a high resistivity '0' state to a low resistivity '1' state is based on the rapid electrical sintering of bits containing silver nanoparticles. The bit ink is formulated by mixing two commercially available silver nanoparticle inks in order to tune the initial square resistance of the bits and to create a self-organized network of percolating paths.

Substrate-facilitated nanoparticle sintering and component interconnection procedure.

Room temperature substrate-facilitated sintering of nanoparticles is demonstrated using commercially available silver nanoparticle ink and inkjet printing substrates. The sintering mechanism is based on the chemical removal of the nanoparticle stabilizing ligand and is shown to provide conductivity above one-fourth that of bulk silver. A novel approach to attach discrete components to printed conductors is presented, where the sintered silver provides the metallic interconnects with good electrical and mechanical properties.

Wireless ferroelectric resonating sensor.

This paper presents a passive wireless resonating sensor that is based on a ferroelectric varactor. The sensor replies with its data at an intermodulation frequency when a reader device illuminates it at 2 closely located frequencies. The paper derives a theoretical equation for the response of such a sensor, verifies the theory by simulations, and demonstrates a temperature sensor based on a ferroelectric varactor.

Electrical sintering of nanoparticle structures.

A method for sintering nanoparticles by applying voltage is presented. This electrical sintering method is demonstrated using silver nanoparticle structures ink-jet-printed onto temperature-sensitive photopaper. The conductivity of the printed nanoparticle layer increases by more than five orders of magnitude during the sintering process, with the final conductivity reaching 3.

Electrostatic transducers for micromechanical resonators: free space and solid dielectric.

Three electrostatic transduction methods are analyzed for a micromechanical, longitudinal mode, beam resonator. The conventional parallel plate transducer placed at the location of maximum displacement is compared to two solid, dielectric transducers internal to the resonator. Although the solid dielectric offers higher permittivity than the free-space-filled transducers, the unfavorable locations of the internal transducers reduce or even remove the performance advantage of the higher permittivity.

Systematic design approach for capacitively coupled microelectromechanical filters.

A design procedure for microelectromechanical (MEMS) band-pass filters is formulated that takes into account specifications set for carrier-to-interference ratio (C/I) and insertion loss. Since suppressing intermodulation distortion to maximize C/I in MEMS filter design typically leads to increased loss and vice versa, it is necessary to aim at a feasible compromise in filter performance that meets all of the requirements. In order to meet specifications that are typical for a handheld communication terminal, an integrated receiver architecture, where filter input and output impedances other than 50 omega can be used, is found to be more feasible than resistively terminating the front-end filter at source and load to 50 omega.