P.S.A. Evans

Capacitive-type humidity sensors fabricated using the offset lithographic printing process

This paper reports on the fabrication of a novel capacitive-type relative humidity sensor of which the electrode films are deposited using the high speed printing process, offset lithography. Parallel-plate capacitor sensor structures have been formed with a number of humidity sensitive polymers including polyimide and polyethersulphone (PES). Details of the fabrication process and sensor characteristics such as linearity, sensitivity and response time are included.

A NOVEL CIRCUIT FABRICATION TECHNIQUE USING OFFSET LITHOGRAPHY

This paper reports the progress in the development of a novel fabrication technique for thin-film electronic circuit boards. The application of this work is in substitutes for resin-laminate circuit boards fabricated by photo-resist and etching processes. Circuit tracks are formed on paper-like substrates by depositing films of a metal-loaded ink via a standard lithographic printing process. Whilst developed primarily for low cost applications, Conductive Lithographic Films (CLFs) have now been successfully demonstrated in a range of telephone plant, microprocessor and microwave stripline applications.

Lithographic film circuits – a review

Conductive lithographic films (CLF) are an emerging fabrication process for electronic interconnect and a range of passive component structures. This paper reviews the manufacture, properties and applications of CLF conductors, and discusses other lithographically deposited electronic materials including resistive, dielectric and ferrite films. Recent developments in CLF technology, including multilayer structures and concurrent printing of interconnect with printed passive components, are presented.

The origins and evolution of the PCB: a review

Many people believe that Eisler invented the printed circuit board (PCB) in the mid‐1930s, but the origins actually lie nearly before 50 years this. If this is true then who invented the PCB? This review offers an alternative view of the history of the PCB including early developments and contributions from the world of art and printing, through innovations in science and engineering to the key developments of the modern electronics industry.

Lithographically printed voltaic cells – a feasibility study

Purpose – It has been shown that circuit interconnects and various passive components can be fabricated on a variety of flexible substrates using the offset lithographic process. This paper reports on a feasibility study investigating the manufacture of voltaic cells deposited via offset lithography.Design/methodology/approach – The Leclanche cell, an established battery chemistry, was chosen as an appropriate technology for adaptation to the offset lithographic process. Development of inks with appropriate rheological properties for lithographic printing was undertaken. Zinc and carbon electrodes were fabricated with silver‐based current collectors. Electrolyte composition was investigated along with separator materials.Findings – Zinc and carbon‐based inks have been produced which result in deposited material appropriate for use as electrodes. A separator material soaked in electrolyte has been combined with these electrode structures and an MnO2 paste to form a voltaic cell. A printed battery, made up ...

INTERDIGITATED CAPACITORS BY OFFSET LITHOGRAPHY

This paper reports on an initial investigation into interdigitated capacitors manufactured via the offset lithographic printing process. Results taken from print-trials reveal the relationship between electrode geometry and capacitance. The paper also identifies a relationship between the substrate characteristics and the behaviour of the capacitive structures. This work is in support of a low cost and low environmental impact approach to circuit board manufacture.

A novel manufacturing process for capacitors using offset lithography

A novel fabrication technique for passive electronic components and circuit interconnects based on offset lithographic printing is described. The application of this work is in low cost and low environmental impact substitutes for resin-laminate circuit boards populated with discrete components. Multilayer ceramic capacitor elements are formed on flexible substrates by depositing layers of metal and ceramic-loaded inks sequentially via a standard lithographic printing press.

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.

Measurement and Modelling of MIC Components Using Conductive Lithographic Films

Conductive Lithographic Films (CLFs) have previously demonstrated useful properties in printed microwave circuits, combining low cost with high speed of manufacture. In this paper we examine the formation of various passive components via the CLF process, which enables further integration of printed microwave integrated circuits. The printed components include vias, resistors and overlay capacitors, and offer viable alternatives to traditional manufacturing processes for Microwave Integrated Circuits (MICs). Manufacturing data, measurements on test structures and equivalent circuit modelling for a range of CLF circuit structures are presented.

42.4: Low Cost, Flexible Electroluminescent Displays with a Novel Electrode Architecture Printed by Offset Lithography

We report flexible, multi-colored electroluminescent displays that are produced using offset lithographic printing of interdigitated electrodes. These displays can be mass produced at low cost as they require no transparent conducting oxides as anode. Applications include back-lighting, large-scale low-cost lighting displays, and low-resolution display technology.