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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.

Polymer thick film (PTF) technology provides the lowest cost, cleanest and most efficient manufacturing method for producing flexible circuits. Non‐contact radio frequency (RF) smart cards and related information transaction devices, such as RFID tags, appear to be a good fit for PTF‐flex. Flip chip also seems well suited for these “contactless” RF transceiver products. Flip chip and PTF adhesive technologies are highly compatible and synergistic. All PTF SMT adhesives assembly methods are viable for flip chip. However, the merging of flip chip with PTF‐flex presents major challenges in design, materials and processing. This paper will compare assembly methods and discuss obstacles and solutions for state‐of‐the‐art flip chip on flex within the RFID product environment.

The properties and constituents of PTF inks are outlined. Surface resistivity in relation to PTF inks is defined. Applications of PTF inks are discussed with emphasis on potential design and cost benefits for SMT applications, including crossovers, polymer multilayer, printing through holes, printed resistors, carbon key pads, moulded and three‐dimensional circuits.

Polymer thick film circuits have been used in consumer appliances, a trend that is growing as one of the major technologies in Japan in this field. This paper discloses the state of the art of the processes involved along with the main features of the circuits. PTF has established a performance that equals that of the cermet type in some applications, which produces cost advantages for PTF circuits on polymer and/or ceramic substrates for wider applications.

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.

This one‐day seminar, repeated in Sweden and Denmark, had its origins in a most interesting co‐operative project which was supported in the four Nordic countries by a total of eleven companies and research organisations. A series of six projects, each relating to a particular aspect of Polymer Thick Film Technology, was agreed by the participants, and the work programme was carried out mainly in national research institutes but with a considerable input from industrial collaborators.

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.

Higher densities and concerns for human health are driving the need for better EMC protection on PCBs in automotive applications. Simultaneously, there is a strong need to reduce circuit costs. Ford, Circuit Wise and Du Pont have worked together to develop the use of polymer thick film (PTF) conductors to provide EMC protection in automotive circuits at a fraction of the cost of adding additional conventional ground plane layers. This paper will discuss the reliability and electrical performance of this approach. The PTF approach is fully compatible with conventional PCB fabrication and assembly processes, including hot air solder levelling and surface‐mounting, and gives EMC protection comparable to or better than that of additional copper ground planes.

The paper introduces the concept of Polymer Thick Film for low temperature resistor and conductor printing. It describes the materials and their characteristics and outlines some of the applications for which PTF can be and is being used.

This paper describes a newly developed Copper PTF (Polymer Thick Film) which is characterised by direct solderability and high electrical conductivity. This Copper PTF claims to solve various problems existing in the conventional subtractive or firing process. It also realises new circuit production processes which are difficult to attain if conventional methods are applied.