NATIONAL PHYSICAL LABORATORY
National Physical Laboratory (NPL) is the United Kingdom's national standards laboratory, an internationally respected and independent centre of excellence in research, development and knowledge transfer in measurement and materials science. NPL’s Electronics Interconnection group have extensive experience in the science and metrology of electronic materials, and world-class facilities for materials characterization and measurements.
The Electronics Interconnection group is led by Dr Chris Hunt who has over 25 years experience in materials science R&D, working on a range of interconnection materials and problems. The team currently has two main thrusts, advanced packing interconnection and printed electronics. This expertise has been built on a world-class position in the characterisation of lead-free reliability, where prediction has been advanced by measurements at a fine scale, typical of solder joints, to achieve accurate FEA models for lifetime estimates of joints. Early studies on polymer interconnect investigated conductive adhesives and circuit assemblies on a range of thermoplastic polymers over a wide range of conditions. Some of these structures were manufactured via a completely additive route using printed interconnect. More recently NPL has worked on end of life of printed electronics, looking at testing of systems that can be disassembled. In another relevant area NPL has studied coating performance, where assemblies are used in harsh conditions. These studies have characterised permeability of aggressive contaminants through a range of polymer systems. In addition NPL has developed electrochemistry and corrosion measurement techniques to diagnose electrochemical reliability problems. NPL has a complete suite of materials analytical facilities, along with a range of environmental stress environments.
The Electronics Interconnection group at NPL have published over 30 peer reviewed papers, and published more than 100 Measurement Good Practice Guides, measurement Notes, and NPL Measurement Reports directly for UK industry. The group has also taken a leading role in the development of 6 new International standards in this area. Furthermore, the team has presented invited talks at 7 international conferences in the past 7 years, and presented widely at international events. Dr Hunt has twice won best paper award at an international conference. He leads a group of 6 full time members of scientific staff, and has taken part in a UK taskforce to Japan on lead-free soldering. He is a member of the Institute of Physics, C.Phys. and sits on various trade body committees, steering board of IMAPS UK and the Steering committee of SMART.
Martin Wickham works within the area of Electronics Interconnection as well as being an independent consultant and Principal Consultant of the Surface Mount Club, a leading independent UK surface mount organisation. In his capacity as a consultant, Martin has worked with NPL for nearly 25 years. He consults on numerous electronic assembly issues, and can provide: process quality audits; implementation budgeting; process planning; soldering yield improvement; design critiquing and assessing; and audits for contract manufacturers.
Chris Hunt leads the Electronics Interconnection team at NPL, which has a number of interests, especially looking at developing materials and characterisation methods. The subject areas include smart textiles, printed electronics and high temperature electronics. For all these techniques, NPL is developing new metrology tools to characterise performance, is developing a novel silver system solution for smart textiles, and for high temperature is developing a carbon nano-tube solution. Chris is also part of a team pioneering a unique solution to achieve recyclable assembly systems with more than 90% recyclability. He has presented widely at international events and published extensively. Chris is chair of the UK BSI committee; has been an active member of IEC TC91: Electronics assembly technology, since 1998, and is currently Chairman until 2021; and participates in IPC committees on electronics assembly standards.
Kate Clayton obtained a first degree in Analytical and Forensic Science, followed by a master's degree in Chemistry and obtained her PhD in the area of conducting polymers from the University of Huddersfield. Before joining NPL, Kate gained experience within QC/QA, product development and project management within the pharmaceutical and consumer goods industries. Kate is interested in using her Chemistry background to understand failure modes within electronic interconnects and is currently working in areas involving tin whisker mitigation, and sintered silver interconnects.
Vimal Gopee obtained a first degree in Physics, followed by a master's in Physics, from the University of Liverpool. He is currently working towards an Engineering Doctorate (EngD) from the University of Surrey on Nanocarbon electronic interconnects.
Vimal has been heavily involved in the development of techniques for the implementation of multi-walled carbon nanotubes in electronic circuits, looking at the chemical vapour deposition methods for carbon nanotube growth and functionalisation effects on the adhesion of carbon nanotubes.