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As an alternative to hot air levelling, a fundamentally new surface finish chemistry and process for solderability preservation of printed circuit boards is described: a pretreatment of the copper followed by an optimized formulation of an immersion tin. The precise and reproducible surface finish formation offers reliable solderability, economic and technical advantages for all kinds of PCBs, even for those with the most modern miniaturized structures. The deposition chemistry and ageing properties of the new Organic Metal/tin surface is discussed, based on electrochemical, wet chemical and electron microscopy studies. The results culminate in an almost complete basic understanding of the tin chemistry and the surface finish performance.

This paper describes the properties of a new generation of immersion tin as a solderable surface finish for printed circuit boards. The new process combines the unique technology of Organic Metals with the well introduced technology of immersion tin. A comparison with other solderable surface finishes will show the advantages and superior performance for PCB manufacturer, assemblers and OEMs.

In August 2007, the European Institute of Printed Circuits produced a Technology Roadmap for the industry for the period 2007‐2017. The purpose of this paper is to give details of the roadmap, the aim of which is to provide information which underpins the aims of the EU‐funded ProSurf project, which are to strengthen European small‐to‐medium enterprises (SME) competitiveness in both the medium‐ and long‐term through increasing knowledge and awareness of high‐tech methods in these industries.

The approach is an outline of the ProSurf project which will enable SMEs to have a clear view of the trends that will affect their businesses in the coming decade, and be delivered in a way that is readily comprehensible.

The summary highlights the present market, the market characteristics, and the position of the European PCB industry today. General factors which influence market trends are listed, within which the demands for miniaturisation and weight reduction, and higher data transmission rates are notable. There are specific requirements of each market sector, viz military, consumer, and automotive electronics, and here the roadmap looks at design rules and manufacturing capabilities. Towards the end of the roadmap attention is paid to the environmental considerations.

The ProSurf technology roadmap is a unique document without peer, and is specific to the European PCB industry whilst having considerable influence in other global areas as the technology demands within Europe impact upon production elsewhere.

The purpose of this paper is to introduce a new class of surface finishes as an alternative to current final surface finishes.

This new finish utilises nanotechnology and is based on a new formulation of the “organic metal” (OM).

The final surface finish is an approximately 50 nm thin permanent layer, consisting of a complex between the OM and silver (Ag). Panels finished with OrmeSTAR™ Ultra show excellent solderability in spite of a low‐layer thickness and therefore offer significant advantages over existing surface finishes.

This new finish has proven to be a competitive alternative to current final finishes with excellent properties for soldering applications. The new nanotechnology can also significantly improve the environmental and economical consequences of solderable surface finishing.

To provide information about latest product developments to address and take away the fear of whisker formation on pure immersion tin surface finishes on PCBs.

This paper summarises the latest findings on whisker formation of pure tin surface finishes and describes an effective methodology for whisker suppression in combination with other benefits for the use of this new immersion tin generation.

Whisker formation is a typical feature of pure tin when coated, e.g. on copper and is a threat to the PCB industry, because of the risks of shortcuts involved. The main driving force for whiskers is an accumulation of internal stress created by diffusion at the boundary of copper and tin. A nano layer deposited from an organic metal‐based pre‐dip significantly reduces the diffusion by creating a unique sandwich layer with smooth concentration gradients. A drastic reduction of diffusion and stress was found, eliminating the driving force for whisker formation and prolonging the layer's shelf life and temperature stability at the same time.

Whenever whisker formation on immersion tin is regarded as a potential risk, e.g. by OEMs, a whisker‐reduced process is available and should be chosen to meet the market's specifications.

This paper takes the edge off the whisker threat discussions, leading to a hesitant implementation of immersion tin surface finish technology for PCBs, which disregard its excellent features with respect to future lead‐free soldering. Whisker‐reduced immersion tin is a viable and preferable alternative solderable surface finish for the lead‐free era.