Pete Starkey’s Five Must-Reads of 2023

Estimated reading time: 4 minutes

My work with I-Connect007 allows me to attend and review conferences and symposia in the UK and Europe. I have the privilege of being among the first to learn about new developments. 

I must say, this has been a good year. We were free at last from COVID travel restrictions and obligatory face masks. This means I have been able to get out and about, network with colleagues in the industry, and report on some notable presentations from distinguished technical specialists in Europe.

It has been a difficult job choosing a “top five” from such a multiplicity and diversity of high-quality papers, but here’s my selection, in date order: 

EIPC Winter Conference: Keynote Emilie Jolivet
In the keynote session of the EIPC Winter Conference in February, Emilie Jolivet, director of the Semiconductor, Memory and Computing Division at Yole Intelligence in France, shared an abundance of forecasts and statistics on IC substrates. These are a key element of the packaging industry, where the significant technology turning points have been the change in material from ceramic to organic and the change in interconnection from wire bonding to flip-chip. The trend towards increasing complexity with larger areas, more layers and finer pitches and lines-and-spaces has led to the adoption of processes like SAP, mSAP and amSAP, together with multiple die embedding technology. 

EIPC Winter Conference: Speaker Frank Tinnefeld
Also, at the Winter Conference, the presentation on Smart Factory Solutions from automation specialist Frank Tinnefeld of ASS-Luippold in Germany described an impressive range of automated tasks in printed circuit manufacture, from simple economic solutions to complex and customised automation. He commented that new production philosophies will enable the realisation of targets like 100% product and process traceability, lead-time reductions by inline production wherever it is useful, automation wherever it is useful, intelligent work-in-process storage solutions with fully automatic interconnection between different process clusters, Smart production planning solutions with the elimination of manual data input and paper travellers, product tracking at all processes, and interface integration for connection to Smart MES or ERP platforms. 

ICT Annual Symposium: Professor Martin Goosey
At the Institute of Circuit Technology Annual Symposium in June, Professor Martin Goosey from MTG Research reported the findings of the ReGail project for the recovery of gallium from end-of-life LED lamps, based on a novel, non-aqueous approach utilising deep-eutectic solvents for both gallium dissolution and subsequent electro-winning. He explained that ionic liquids and eutectic solvents are environmentally low-impact, inexpensive materials with unusual solvation properties for metal salts that have proven useful in metal finishing applications. Initial work has indicated that gallium and indium can be electrodeposited from deep-eutectic solutions and that indium is deposited at a much lower cathodic potential than gallium. This provides a mechanism for separating the metals once they have initially been dissolved using an electrocatalytic dissolution process with iodine as an oxidant, itself regenerated at the anode during the electrodeposition stage, offering an elegant, no-waste, closed-loop process.

EIPC Summer Conference: Alex Stepinski
At the EIPC Summer Conference, also in June, Alex Stepinski, one of whose many areas of expertise is wastewater recycling, explained how to economically upgrade existing European PCB fabrication facilities to 100% zero liquid discharge. He advocates an advanced oxidation process to remove organics and break chelates, followed by settlers and filters to remove metal hydroxides and other suspended solids. A membrane system recovers 99% of the liquid as ultra-pure de-ionised water and the remaining 1% is recovered by vacuum distillation to leave a solid sludge from which individual metals can be extracted. Systems have been deployed across four new factories in the U.S. over the past five years and have passed U.S. EPA audits. The first projects in Europe and Asia are already underway. He estimates that total system CapEX and 10 years’ maintenance will be covered by three to 10 years of OPEX savings without EU funding.

IPC Day Netherlands: Stan Heltzel
At the IPC Day Netherlands: Aerospace Electronics in October, Stan Heltzel, ESA’s materials and processes engineer, brought us up-to-date with how PCB technology is advancing in European space applications, with reference to a few current and future missions: BepiColombo on its way to Mercury, Solar Orbiter, Rosetta the comet chaser, JUICE on its way to Jupiter’s moons, the Galileo constellation medium-Earth-orbit global navigation satellite system, and a whole range of geostationary telecommunications systems. Human spaceflight missions included the International Space Station and the Lunar Gateway. He illustrated the life cycle of a PCB in a space project step-by-step, from procurement through project review, assembly, and final integration into a system. He described how PCBs are qualified for space applications: ECSS-Q-ST-70-60C is the standard for qualification and procurement of printed circuit boards, with ESA and the French Space Agency CNES as the qualification authorities. Heltzel discussed ESA’s HDI roadmap and emphasised the importance of early involvement and making the PCB manufacturer a partner in the supply chain.