EIPC Technical Snapshot: Sustainability in Electronics Manufacturing

Estimated reading time: 5 minutes

EIPC selected the highly topical issue of sustainability in electronics manufacturing for the 24th Technical Snapshot webinar on Oct. 29, with guest speakers Satoshi Konagai of Elephantech and Liisa Hakola of the VTT Technical Research Centre of Finland.

The program was moderated by Kirsten Smit-Westenberg, executive director of EIPC, who also introduced each speaker.

The opening presentation came from Liisa Hakola, senior scientist and senior project manager at the VTT Technical Research Centre of Finland. Her research area takes a holistic approach to the sustainability aspects of flexible electronics, from the design stage, to materials and manufacturing, to the in-use phase and final disposal of devices, and had the facility to develop printed electronics from laboratory scale through to pilot scale manufacture. 

She described the aim of sustainable development as bringing together economic, social, and environmental considerations in ways that mutually reinforce each other to meet the needs of present generations without jeopardizing the ability of future generations to meet their own needs. 

Circularity is a particularly important consideration for the electronics industry as electronic waste continues to increase rapidly while material resources are getting fewer. Regulations and global trends are forcing the electronics industry to consider environmental aspects at all stages of the product development process. It is estimated that 80% of environmental impacts are identified during the design phase, where sustainability and circularity must be viewed as priorities.

Hakola is currently working as a technical manager in a major European ecosystem project named Sustronics, coordinated by Philips in the Netherlands, and focused on addressing the sustainability challenges of electronics manufacturing and reaching regulatory goals. The three-year project has 46 partners from 11 countries, combining large enterprises, SMEs, research organisations and universities throughout the electronics value chain and life cycle, funded under the CHIPS Joint Undertaking.

It set out to build an ecosystem to demonstrate how the electronics industry can benefit from sustainable materials and manufacturing, eco-design, energy-efficient products and circular business models, bringing the whole sector closer to meeting Green Deal objectives while improving its competitiveness and strategic autonomy.

Ten pilot projects are ongoing across three use-cases: circular electronic devices, sustainable manufacturing for electronics, and environmentally compatible single-use electronics, to demonstrate sustainability and circularity: 

In the use-case of electronics manufacturing, the pilots are focused on bio-based renewable materials and sustainable manufacturing methods. Hakola illustrated the potentially dramatic benefits in environmental impact that can be achieved with printed electronics. Her example indicated that by replacing a conventional etched-copper PCB process with printing-based methods, its global warming potential can be reduced to 14% of the original value. Furthermore, the global warming potential of printed electronics based on silver nanoparticle inks and polyester substrates can be significantly reduced using copper or carbon nanoparticle inks and bio-based substrates.

She commented that the Ecodesign for Sustainable Products Regulation (ESPR), which came into force on 18 July 2024, was the cornerstone of the European Commission’s approach to more environmentally sustainable and circular products, and that Digital Product Passports, providing transparency and traceability, will become the norm for all products placed in the EU market

She closed by commenting that resource sufficiency is a global challenge concerning all businesses, including the electronics sector, and that business opportunities can be found at many levels from sustainability.

With Liisa Hakola having referred to some of the sustainability benefits of printed electronics, the following presentation from Satoshi Konagai, head of marketing with Elephantech in Japan, gave an in-depth description of a novel additive process using inkjet-printed copper nanoparticle ink that enables significantly more sustainable production of copper circuits and allows PCB manufacturers and OEMs to reduce environmental impact while maintaining reliable performance.

Founded in 2014 as a start-up at the University of Tokyo, Elephantech has built strong capital and business alliances with leading Japanese corporations as a core strategy to drive transformation in the electronics industry through innovations in inkjet technology. After several years in R&D, the company has successfully scaled up with recognition by the market and is in a position to supply equipment and materials for mass production.

Figures quoted by Konagai indicate a PCB-related annual global carbon footprint of 66 million tons of carbon dioxide, with PCBs contributing 30% of the overall carbon footprint of smartphone production, 25% of that in laptop production, and 10% of Apple’s total activity.

Mainstream subtractive-technology PCB manufacturing was characterised by excessive wasted copper from the etching process, up to 70% of the original laminate copper according to Konagai’s figures. He proposed a fully additive alternative, a proprietary low-carbon PCB manufacturing technology offered by Elephantech, and described the main process steps in detail, using unclad FR4 base material as a substrate example. 

The substrate is first coated with a highly adhesive primer and heat-cured. The primer ensures strong bonding with the conductive ink printed at the imaging stage. A thin protective film is applied before drilling the via holes, which are then made conductive by printing copper nanoparticle ink directly into them, rather than using electroless copper plating. After removal of the protective film, an inkjet printing operation produces a conductive image of the circuit pattern in copper nanoparticle ink, with all of the features effectively shorted together by what he termed “power supply lines.”

After a drying process, the conductor pattern is treated with a reducing agent then brought to the required thickness by copper electroplating without the need for any plating resist, with the power supply lines being subsequently removed by laser or NC router. Fifty micron lines and spaces are within the capability of the process, which eliminates electroless copper plating, photoresist imaging, and the develop-etch-strip sequence, as well as reducing copper usage, and substantially reducing water consumption, enabling significant cost reductions and presenting a strong environmental value proposition. 

The adhesion mechanism is worthy of particular mention: Peel test results significantly exceed the acceptance criteria of IPC-6012. An interaction between the glycol-based copper nanoparticle ink and the epoxy-based primer result in the primer layer rapidly absorbing the solvent from the ink, allowing the ink to settle instantly without spreading, and to form an interlocking nanostructure with the primer layer, ensuring high adhesion and instant ink fixation. This effect also enhances the fine-line imaging capability of the inkjet system.

Elephantech has adopted a dual business model to promote industry-wide sustainability. They offer in-house-manufactured PCB products in addition to equipment and materials sales. Several major OEMs have endorsed the technology and recognised it as cost-effective and environmentally friendly. 

These two webinar presentations stimulated an interesting and informative Q&A session, capably managed by Kirsten Smit-Westenberg, who then brought a very successful event to a close by thanking all who had participated.