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Ten years ago, long before surface mounting became an issue for mass production, the role of the printed circuit designer was mainly to design a conductive interconnect with through‐hole mounted connecting pins. At this time, manufacturing technology was very little influenced by the circuit designer, since all components were inserted into through‐holes and only a few basic rules were required for the soldering of the through‐hole mounted components.

This paper details the impact of “Coefficient of Thermal Expansion” (CTE) imbalances caused by the different materials used in a Printed Circuit Board (PCB). It will also provide guidance as to how the PCB manufacturing process can be modified to accommodate the new requirements from PCB fabricators, assemblers and OEMs for high dimensional consistency of the laminate and prepreg to improve manufacturing yields in bare PCB fabrication, in assembly and during the life‐cycle of the electronic device in the field.The paper also explains the risks associated with metal migration and cathodic/anodic filaments (CAF) in PCBs, the impact of a lower CTE and a lower dielectric constant (Dk), as well as the need to minimise the differences of CTE between the PCB laminate and the package/chip in order to better manage the higher stress incurred by the use of lead‐free soldering materials. New materials are discussed which are processable in standard PCB fabrication lines, and which can accommodate the needs engendered by halogen‐free resin systems.

This paper seeks to present an overview of the importance of standards for PCBs when doing business in Europe and to provide information that will enable a better understanding of how to meet their requirements.

A review of PCB standards and their implementation processes in different countries of Europe and further afield was conducted.

By applying the latest technical and ecological standards in a correct way and differentiating between “must have” and “desired” in a weighted process, a greater likelihood of success in business dealings will be achieved.

This paper has highlighted the importance of producing PCBs to the required specifications of the end‐user and the locally implemented standards. Each potentially important standard needs to be identified in the context of the products being supplied, the end customer application and the specific regional requirements.

The paper details how individual standards are applied to printed circuit boards and circuit board materials. It outlines the important considerations that have to be taken into account when supplying PCBs to European customers.