National Physical Laboratory

Improving Electronic Reliability - Through Product and Process Qualification at NPL (Webinar series)



NPL's Electronic Interconnection Group is presenting a new series of technical webinars in 2015.

Recordings of previous webinars are available here

This Group is internationally recognised for its practical and innovative work on lead-free reliability, PCB interconnection failures, tin whisker migration and conformal coating research.

These FREE online webinars provide the opportunity to draw on years of practical experience without the participant needing to leave his/her desk - to participate, all that is needed is a phone line and Internet access. Please note that registration is essential.

Each webinar lasts approximately 60 mins (and is limited to 100 delegate/company registrations). After the webinar, participants receive a copy of all of the slides and a listing of all relevant technical reports which can be downloaded for FREE.

Please note that all webinars are at UK time - check local time in other countries here




Smart Textiles for Wearable Technology
Presented by Roya Ashayer-Soltani, NPL

Monday 16 March 2015 (14:30 hrs UK time)

Book your place here

There is an increasing demand for wearable electronics from industries such as sport and fitness, consumer electronics, medical and healthcare applications. Smart textiles with wearable technology have the potential to change the way we manage our health, respond to emergency, communicate and entertain ourselves.

Currently, weaving or knitting a metal wire is the most commonly-used method for making a conductive textile. However, true wearable technology should be integrated within the clothing with maximum comfort and minimum visibility. The conductive textile solution we present here could make this possible. Currently, there are significant challenges for wearable electronics which needs to be overcome, e.g. a critical performance metric for future smart textiles is the ability to withstand multiple wash cycles. Also, there are environmental concerns regarding the release of metals in the form of nanoparticles.

This webinar will provide information regarding existing technologies, developments and challenges facing the wearable market.

Topics will cover:

  • Why wearable technology?
  • Market opportunities
  • Limitation of existing processes
  • Available manufacturing techniques
  • Advance techniques fabric technology

This webinar will run for between 45-60 minutes, with a Q&A session. The webinars are limited to 100 delegates/companies. A copy of each of the slides presented and links to NPL reports will be provided after the webinar.



Characterisation and Life-time Prediction of Printed Electronics Interconnects
Presented by Martin Wickham, NPL

Monday 11 May 2015 (14:30 hrs UK time)

Book your place here

The Electronics Interconnect Group of the National Physical Laboratory has been involved with characterising printed electronics systems for more than a decade. Initially evaluating conductive adhesives for SnPb replacement, this led to collaborative projects in developing highly recyclable printed circuit assemblies (ReUSE) based on printed conductor tracks, dielectrics and conductive component attachment. Subsequent collaborative research has included performance and lifetime testing of carbon, silver and graphene printed inks on flexible substrates such as PET and PEN. More recently, we have been investigating methods for interrogating wet inks to determine their fully cured electrical performance and also looking at printed electronics defect characterisation and detection. Our current projects include characterisation of electrochemical inks and investigating methods of defect detection for high-speed printed electronics manufacture. Examples of our work over the last decade in developing a suite of measurement techniques for characterising printed electronics systems will be given. Details of the characterisation and testing services for printed electronics interconnect that are available at NPL will be detailed.

This webinar will run for between 45-60 minutes, with a Q&A session. The webinars are limited to 100 delegates/companies. A copy of each of the slides presented and links to NPL reports will be provided after the webinar.


Tin Whisker Mitigation Measurements using a Test Vehicle based on a Printed Circuit Assembly
Presented by Martin Wickham, NPL


Monday 13 July 2015 (14:30 hrs UK time)

Book your place here

Conformal coating of assemblies has been pursued as a mitigation strategy for tin whiskers by a number of organisations across avionics, space and other high reliability applications. The National Physical Laboratory has led a number of collaborative projects with industry to develop test vehicles to enable measurement of the effect of applying mitigation strategies to tin-plated copper. NPL, along with 15 industrial partners, has developed a new test vehicle based on specially plated SOIC components mounted onto PCBs, allowing the coating challenges of an actual surface mount assemblies to be tested. During trials on test vehicle assembly methods, the effect of different thermal profiles on whisker formation has been determined. The project is now in the final phase of long-term testing of a range of mitigation strategies. Over 2,500 components have been coated for the study using 20 different conformal coatings covering acrylics, polyurethanes, urethane acrylates, paraxylenes, fluorocarbons and silicones. Analysis of the uncoated control assemblies and early prototypes has given valuable data on how whiskers cause shorts and intermittents to develop on unprotected printed circuit assemblies. The importance of the frequency of testing has also been determined. Details of early failures in coated samples will also be given.

This webinar will run for between 45-60 minutes, with a Q&A session. The webinars are limited to 100 delegates/companies. A copy of each of the slides presented and links to NPL reports will be provided after the webinar.



Practical Applications of Carbon Based Nanomaterials in Electronics
Presented by Vimal Gopee, NPL

Monday 14 September 2015 (14:30 hrs UK time)

Book your place here

The extraordinary properties exhibited by metallic carbon nanotubes (CNT), which arise from their perfect self-organised crystal structure, make these materials attractive candidates for electrical interconnects. This webinar will look at methodologies that being developed for implementation of CNT interconnect systems, synthesised at low temperature, in accordance with the ITRS roadmap. Another key aspect for industrial take-up is the development of dependable tests of performance and reliability which, due to the unique material properties, will require innovative metrology. The challenges in this area will be presented and the possible solutions discussed, and will include advances made in this area to date.

Topics covered:

  • Properties of CNTs
  • Adhesion of CNTs to surfaces
  • Conditioning of CNTs in order to improve adhesion
  • Wetting of CNTs with solder
  • Interconnections using sintered silver
  • Reliability testing of CNTs
  • Health and safety: what are the risks?

This webinar will run for between 45-60 minutes, with a Q&A session. The webinars are limited to 100 delegates/companies. A copy of each of the slides presented and links to NPL reports will be provided after the webinar.



CAF Conductive Anodic Filaments - How to Avoid Failure
Presented by Ling Zou, NPL

Monday 16 November 2015 (14:30 hrs UK time)

Book your place here

Conductive Anodic Filamentation (CAF) is a subsurface failure mode for woven glass-reinforced laminate (FR4) materials, in which a copper salt filament grows and results in a consequential electrical short between plated through-hole (PTH) walls or adjacent copper planes. In this webinar we cover FR4 laminates, in the form of high PTH density multi-layer test circuits, exposed to different manufacturing conditions and studied for resistance to CAF initiation and growth. CAF performance was assessed using high temperature and humidity conditions to promote failures, with a voltage applied across adjacent vias. By application of a range of voltages and via geometries, the basis for a performance map for laminates was obtained for use in materials comparison. The changes due to exposure of laminates to lead-free temperatures and other processing steps were then examined using the technique, and a number of important recommendations made regarding minimising the possibility of CAF initiation and growth. A new approach to characterise CAF processes has been developed using a Simulated Test Vehicle (STV). The STV, can be easily built under controlled condition in the laboratory using different glass fibres and resin power to investigating effect of different variables on CAF separately. The advantage of STV will be described and examples of material studies that can be undertaken presented.

Topics covered:

  • What is CAF?
  • How does failure occur?
  • Testing techniques
  • Testing performance
  • Failure modes
  • Design and its impact on CAF
  • Latest research work on CAF

This webinar will run for between 45-60 minutes, with a Q&A session. The webinars are limited to 100 delegates/companies. A copy of each of the slides presented and links to NPL reports will be provided after the webinar.

Last Updated: 26 Jan 2015
Created: 4 Apr 2011