Integrated capacitors for conductive lithographic film circuits

This paper reports on fabrication of low-value embedded capacitors in conductive lithographic film (CLF) circuit boards. The CLF process is a low-cost and high speed manufacturing technique for flexible circuits and systems. We report on the construction and electrical characteristics of CLF capacitor structures printed onto flexible substrates. These components comprise a single polyester dielectric layer, which separates the printed electrode films. Multilayer circuit boards with printed components and interconnect can be fabricated using this technique

Via and embedded resistor production in low cost lithographically printed substrates

Lithographic printing of silver based conductive inks to form circuit tracking provides a very low cost, environmentally friendly method of production. It allows circuits with line widths down to 100 μm and a sheet resistance of 0.3 Ω per square to be produced at rates of up to 10000 impressions per hour. The process makes use of low capital cost equipment and has low set up costs. To date, an equally cost effective method of manufacturing vias in these circuits has not been developed. This paper proposes two new techniques for via production which are compatible with the rest of the manufacturing process. In the first technique, suitably profiled holes are laser drilled for subsequent filling as part of the lithographic printing. In the second technique laser energy is used to melt the substrate material so that it is able to mix with the conductive ink and so form a conductive path. The paper describes the proposed production techniques and discusses the factors affecting each method and in particular the substrate properties affecting production. The substrate materials considered in detail are Glossart and Teslin. The optical absorption and ablation characteristics of these materials for excimer and CO2 lasers are reported, as are the thermal diffusivities

Characterization of lithographically printed resistive strain gauges

This paper reports progress in sensor fabrication by the conductive lithographic film (CLF) printing process. Work describing strain-sensitive structures manufactured using a modified printing process and conductive inks is addressed. The performance of a "single-ink" strain-sensitive structure when printed on six alternative substrates (GlossArt, PolyArt, Teslin, Mylar C, Melinex, and Kapton) is analyzed. Though not intending to compete with conventional gauges in high-tolerance measurement, the structures exhibit properties that indicate suitability for novel applications

Conductive lithographic film fabricated resistive strain gauges

This paper reports progress in sensor fabrication by the conductive lithographic film (CLF) printing process. Work describing strain sensitive structures manufactured using a modified printing process and conductive inks are addressed. The performance of a 'single ink' strain sensitive structure when printed on six alternative polymer substrates (GlossArt, PolyArt, Teslin, Mylar C, Mylar and Kapton) is analysed. Though not intending to compete with conventional gauges in high tolerance measurement, the structures exhibit properties that indicate suitability for novel applications

Polyaniline/palladium nanohybrids for moisture and hydrogen detection.

Palladium nanoparticles display fascinating electronic, optical and catalytic properties, thus they can be used for various applications such as sensor fabrication. Conducting polymers such as polyaniline have also been widely used in sensor technology due to its cost effectiveness, versatility, and ease of synthesis. In this research, attention was given to unify the exceptional properties of these two materials and construct palladium nanoparticle coated polyaniline films to detect hydrogen and moisture. Electrochemical polymerization of aniline was carried out on gold sputtered epoxy resin boards. Polyaniline film was generated across a gap of 0.2 mm created by a scratch made on the gold coating prior to electrochemical polymerization. A palladium nanoparticle dispersion was prepared using sonochemical reduction method and coated on to polyaniline film using drop-drying technique. Polyaniline only films were also fabricated for comparative analysis. Sensitivity of films towards humidity and hydrogen was evaluated using impedance spectroscopy in the presence of the respective species. According to the results, polyaniline films exhibited an impedance drop in the presence of humidity and the response was significantly improved once palladium nanoparticles were incorporated. Interestingly, polyaniline only films did not respond to hydrogen. Nevertheless, palladium nanoparticle coated polyaniline films exhibited remarkable response towards hydrogen