Plastic Flexible Electronics Substrates Featuring Polyester Films

Continued advances in Flexible Hybrid Electronics have required material suppliers to deliver improved functionality to the device developers in broad applications such as sensors, displays, barrier films, photovoltaics, medical diagnostics, consumer electronics, HMI (Human Machine Interface), and Flexible Printed Circuits (FPCs).

Demands on the flexible plastic substrate suppliers can vary widely, with the polymer film’s property requirements typically including some combination of: clean surfaces with low surface defects, optically clear films with low haze and iridescence, minimal thermal shrinkage for multilayer print registration, ability to withstand high temperature processing for component attach via solder reflow, UV and Hydrolysis resistance for weatherability, VTM-0 flame retardance, and environmental sustainability. Many requests also include an ability to further tailor the surface chemistries to improve and enhance the downstream coating performance.

New commercial PET and PEN polyester film types have been introduced, and their typical end use applications will be described. Flexible substrate selection requires a keen understanding of, and often a trade-off and compromise between, performance and cost. At a high level, several enhanced polyester films will be compared against a few alternative plastic film types. In summary, polyester films are uniquely capable of offering customized and affordable substrate solutions for many flexible electronics applications.