About the project

Flexible circuit boards are a functionally pivotal and rapidly growing technology for electronics goods. Applications include; computer peripherals (e.g. flat panel displays, ink-jet printers, disc drives), hand held devices (e.g. GPS, personal digital assistants, membrane keyboards), telecommunications (mobile phones), automotive (e.g. engine controls, dashboards/connections), smart cards (antenna foils), aerospace (lightweight, compact systems) and medical devices (e.g. sensors). The drive to use flexible circuits is based on the technologies ability to: reduce size, weight, assembly time and cost, accommodate relative movement between component parts, increase system reliability (reduced interconnect), improve controlled impedance signal transmission and heat dissipation and enable three dimensional packaging.

These benefits have resulted in a significant increase in the use of flexible circuits for electronics and systems assembly, particularly consumer products. The global market size has been estimated by various bodies to be between 4 billion to 7 billion with anticipated growth rates up to 15% per year.

Flexible circuits are most commonly manufacture using one or two base materials, either polyimide or polyester. The former is favoured where soldering is required, the latter is generally used in low cost applications. Both flexible circuit material systems are sensitive to temperature (continuous service temperature: polyimide ~177°C, polyester ~74°C), which raises considerable concerns as to their capabilities of withstanding the higher soldering temperatures, which will be imposed by lead-free solder and its impact on their operating properties. As flexible circuits are developing into such a significant technology for electronic products, with a major role in manufacturing and assembly being played by SMEs, it is essential that an understanding of the impact of this major change in technology on flexible circuits is understood and solutions found.

This project is aimed at assisting SMEs in electronics products by establishing solutions to the assembly of flexible circuits when lead-free soldering is introduced and through this opening up new opportunities via development of new environmentally friendly technology for current and next generations of electronics products.