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The purpose of this paper is to study high-voltage interactions in polymer thick-film resistors, namely, polyvinyl chloride (PVC)-graphite thick-film resistors, and their applications in universal trimming of these resistors.

The authors applied high voltages in the form of pulses and impulses of various pulse durations and with different amplitudes to polymer thick-film resistors and observed the variation of resistance of these resistors with high voltages.

The paper finds that high voltages can be used for trimming of polymer thick-film resistors in both directions, i.e. upwards and downwards.

The research implication of this paper is that polymer thick-film resistors can be trimmed downwards or upwards practically using this method.

The practical implications of this paper is that one can trim the polymer thick-film resistors, namely, PVC–graphite thick-film resistors, in both directions, i.e. upwards and downwards, by using this method.

The value of the paper is in showing that high voltages can be used to trim downwards and also upwards in the case of polymer thick-film resistors. This type of trimming is called universal trimming, developed first time for polymer thick-film resistors.

The purpose of this paper is to study the microwave interactions in polymer thick film resistors, namely, polyvinyl chloride (PVC)-graphite thick film resistors, and its applications in trimming of these resistors.

We applied microwave radiation in the form of pulses of various pulse durations and with different powers to polymer thick film resistors and observed the variation of resistance of these resistors with microwave radiation.

The paper finds that microwave radiation can be used for trimming of polymer thick film resistors.

The research implication of this paper is that polymer thick film resistors can be trimmed practically using this method.

The practical implication of this paper is that we can trim the polymer thick film resistors, namely, PVC-graphite thick film resistor, by using this method.

The value of the paper is in showing that microwave radiation can be used to trim downwards in the case of high-value resistors and trim upwards in the case of low-value resistors.

Polymer thick film, as an additive process for making circuitry, is not new but has recently received considerable attention. The process has a number of attractive features to offer and when radiation curing is used to accelerate the curing process the technology becomes even more attractive. To be accepted by industry on a large scale, however, these materials must be certified by independent circuit board testing laboratories. Using infra‐red as the curing process, Methode prepared a polymer thick film version of a test pattern used for testing to Mil 55110 and produced some very promising results.

Materials based on polymer films which are deposited by a screen printing process onto an inert substrate are finding innumerable applications in the fabrication of circuits in modern electronic assemblies. At one time the concept of ‘polymer thick film’ (PTF) technology might have been seen as an alternative to printed circuits on organic substrates or to thick film circuits on ceramic. The point is made here that, resulting from the very diverse range of materials now available, it is better to regard PTF as a supporting technology to be used in conjunction with other techniques from printed circuit or hybrid film technology. There are many examples where individual PTF materials have been selected and used in assisting or enabling roles with obvious technical advantages and significant commercial benefit.

The purpose of this paper is to give an overview of the benefits and challenges of different technologies for via replacement in the realization of flexible substrates with more than one layer.

The paper details the use of traditional technology for via formation and discusses the placement of jumpers (0 Ω resistors) and polymer thick film printing as alternative methods.

The paper covers a selection of possible techniques for replacement of vias. The results demonstrate the capability of polymer thick film pastes on flexible substrates. Depending on the requirements of the application and the operating environment, use of other substrate materials opens up a large variety of possible solutions.

The paper details the different techniques for via replacement and gives information about the different technological approaches.

The paper gives design guidelines for polymer thick‐film technology (PTF). After an introduction reviewing the main PTF properties, materials and processes, detailed PTF design rules are presented. They are conservative, to achieve high production yield. The design rules are based on the considerable experience in the companies of the authors and of the persons mentioned in the acknowledgements, as well as on information from the open literature and from materials suppliers. The design guidelines are intended primarily for designers, but they are also important for production personnel, to facilitate a close coupling between design and production, and thus provide optimum use of PTF and obtain high production yield.

The paper describes the results obtained by the integration of Polymer Thick Film and Printed Circuit Technologies. Polymer Thick Film (PTF) Technology, applied to PCB manufacturing, helps the designer's task considerably and offers an interesting way to achieve time and cost reduction. The use of conductive and dielectric materials to generate cross‐overs and low interconnection density multilayers on epoxy‐glass substrates is shown and basic design rules are discussed. The performances of PTF conductive materials from two different suppliers are investigated in terms of conductivity, current carrying capacity and contact resistance with the copper‐clad layer. Surface and bulk insulation resistance, capacitance, loss factor and breakdown voltage are studied for dielectric materials from two different suppliers. The effects of environmental tests, i.e., thermal shocks, high temperature storage and temperature‐humidity‐bias test, on the performances of dielectric and conductive PTF are investigated by means of suitable test patterns. Application examples of Transmission System boards are discussed in terms of design and manufacturing times and costs.

The paper aims to verify the influence of mechanical factors (longitudinal elongation at constant stretching velocity, constant elongation strain and cyclic compressive and tensile stresses) on the electrical properties of thin-film and polymer thick-film resistors on flexible substrates.

Kapton foil was used as a substrate for all test samples. Designed resistive structures were made with the aid of two polymer thick-film resistive inks or OhmegaPly Ni-P resistive foil. Two different topologies – the horseshoe and triangular – were used. These topologies should have the opposite stability parameters.

Almost all presented data confirm the influence of the topology of resistors on stability of their electrical properties. The resistive materials applied for test structures also affect the stability under various mechanical exposures.

In general, the largest changes were caused by longitudinal elongation at constant stretching velocity, whereas other tests caused smaller changes of electrical properties. The measurements confirm the influence of topology on stability of electric properties.

This paper concisely describes polymer thick film technology used with printed circuit boards as an interesting means of achieving time and cost reduction. Telephone keypads and edge connectors manufactured with this technology and using two different processes are subjected to environmental and life tests in order to compare them with the traditional gold‐plated keypads and edge connectors used in the same applications.

The use of polymer thick‐film technology for the implementation of piezoelectric sensors opens up the way towards the low‐cost production of piezoelectric sensing devices. A novel polymer thick‐film piezoelectric paste is presented and compared with other piezoelectric materials. The main advantages of these films are the low processing temperature, their flexibility and the ease of creating patterns with feature sizes as small as 200μm. Various applications are proposed demonstrating the potential of these screen printable polymer piezoelectrics.