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Happy’s Tech Talk #41: Sustainability and Circularity for Electronics Manufacturing

I attended INEMI’s June 12 online seminar, “Sustainable Electronics Tech Topic Series: PCBs and Sustainability.” Dr. Maarten Cauwe of imec spoke on “Life Cycle Inventory (LCI) Models for Assessing and Improving the Environmental Impact of PCB Assemblies,” and Jack Herring of Jiva Materials Ltd. spoke on “Transforming Electronics with Recyclable PCB Technology.” This column will review information and provide analysis from both presentations.

Life Cycle Inventory Models
Dr. Cauwe noted that over the past several years, there has been rapid growth in technologies designed to mitigate the effects of climate change. We have made great strides in broader sustainability targets, particularly in recycling, use of renewable chemicals, and overall process efficiency, resulting in energy savings. 

PwC’s recent report on sustainability1 shows that companies find sustainability valuable to their businesses. Rising energy demands, evolving customer (OEM) expectations, and a perceived long-term competitive advantage are factors that keep companies focused on sustainability and circularity, including decarbonization, waste, and obsolescence. 

Life Cycle Assessment (LCA)
Europeans have always taken the lead on environmental concerns. The PEP ecopassport program for electronics manufacturing is a framework for creating and publishing environmental declarations (PEP) with a database that assesses the environmental impact contributed by electronic assemblies. It is based on LCA and contains detailed data on materials, energy, water usage, and waste generation for various components (Figure 1).

We perform this using the LCA, a combination of LCI and LCIA. LCI quantifies products’ inputs and outputs, while LCIA assesses the environmental impacts.

Life Cycle Impact (LCI): Assembles data on all materials entering and leaving (a so-called materials balance) the fabrication or assembly process at an electronics product facility (ISO) to create a parametric LCIA model

Life Cycle Impact Assessment (LCIA): Engineers design LCIA models for use in a range of manufacturing processes and product designs. Inputs include design data, energy, water, and waste for PCB manufacturing processes.

Parametric LCI
The Figure 2 model is from PCB manufacturers and assemblers and includes product volumes, line capacity, and generated waste. Unfortunately, the model assumes 100% production yields for simplification, which affects accuracy. The program also has no way of verifying the accuracy of the reported data. Static and aggregated datasets to create design-dependent production LCI models should require some ISO standard for validation. 

The PCB Manufacturing LCI Model
The parametric PCB model in Figure 3 is designed to facilitate material sourcing, electronics manufacturing, product use, and end-of-life considerations in the design phase. This is an ambitious mission meant to help OEMs reach their environmental sustainability targets. 

The detailed PCB LCI model is based on a standard four-layer multilayer, with inputs and outputs normalized for 1 m2 of output. The panel occupation (number up on a panel represented as a percentage) is an important parameter in the model calculating energy, water, chemicals and generated waste.

Twelve-layer Board Example 
A 12-layer FR-4 board was 156 mm x 140 mm and 1.8 mm thick, using ENIG with solder mask. Figure 4 shows the model results, summarizing energy, treated water, and DI water usage in graph form.

The high energy usage of 2.49 kWh/m2 stems from using gold in ENIG because gold and other noble metals require high energy consumption in refining and processing. The lowest are immersion silver, tin, and OSP.

Summary
I have previously collaborated with Cauwe on UHDI reliability with the IPC UHDI Standards Committee (D33-AP). This is a new role for him at imec in Europe, but his prior work in the EU Space Agency on advanced UHDI is notable.

There was a clear model correlation with eco design specifications based on: 

• Base material types 
• Panel utilization (panel occupation) 
• Total layer count 
• Yields 

Over the years, I developed my own PCB panel model in conjunction with the MCC program, which focuses on semiconductor technology, circuit schematics, and component packaging (I/Os and pitch) to provide costs, density requirements, design rules (layers), electrical performance and estimated first-pass-yields, but not eco elements. As this EU LCI model develops, I may add these to my modeling software. 

What appears to be driving this work is: 

• Eco-design: Regulation (EU) 2024/1781 of the European Parliament and of the Council, establishing a framework for the setting of eco-design requirements for sustainable products, amending Directive (EU) 2020/1828 and Regulation (EU) 2023/1542 and repealing Directive 2009/125/EC (OJ L, 2024/1781, 28.6. 2024)
• Creation of the LCA database and manufacturing models to collect data from suppliers and fabricators 
• Eco-reporting: To amend the corporate sustainability reporting Directive (EU) 2022/2464 of the European Parliament and of the Council (Dec. 14, 2022) 
• Create eco-improvement targets for water, materials, energy, and waste 

Let’s hope these regulations are well-researched and well thought out (unlike the lead-free solder regulations). There is likely to be an impact on the U.S. as China seems involved and interested. My models indicate that HDI and UHDI technologies significantly impact boards in terms of materials, size, yields, and layer count reduction.

Transforming Electronics with Recyclable PCB Technology
Jack Herring discussed his UK company's efforts to develop a biodegradable laminate suitable for electronics. This new copper-clad laminate is called Soluboard. While traditional FR-4 uses glass cloth and complex thermoset resins, Soluboard uses natural fibers coated with biodegradable materials, allowing the laminate to be broken down at end-of-life. This enables the recovery of metals that would otherwise be lost and offers a 68% lower carbon footprint compared to standard FR-4 (Figure 5). 

There are several large corporations concerned with obsolescence and end-of-life. Experts estimate that by 2030, more than 6.5 million tons of waste PCBs will be produced and end up in landfills. The Soluboard represents a way to manufacture rigid PCBs with a laminate that can be a drop-in replacement for double-sided FR-4 in standard PCB fabrication, which can then be recycled at end-of-life with a certified non-hazardous hot water-based process. 

Jiva has been working on a suitable FR-4 replacement since its founding in 2017 (Figure 6). Products now include: 

• Jute prepreg 
• Flax prepreg 
• Additive manufacturing of printed electronics substrates 
• The new rigid copper-clad FR-4 replacement 

Manufacturing Process
The production process is continuous, allowing for a lower carbon footprint. We have not seen this used for rigid laminates since the discontinuation of Glasteel Industrial Laminates (GIL-1000) in 2003 (Figure 7).

The current Soluboard product for a 1.6 mm laminate has a 68.38% lower CO2 footprint than standard FR-4, derived from lowering the kg/m2 generated in manufacturing materials-processing and transportation. If assembly switches to low-temperature solder (LTS) to reduce the reflow oven energy (by 40%), then a savings of 11.7 kWh is achievable annually, as well as a CO2 drop in emissions of 1.11 tons per week per oven or 57.2 tons per year.

The biodegradable composite materials include hydrophobically modified polyvinyl alcohol (PVA) with a halogen-free flame retardant (organic phosphonate).

Jute, flax, or hemp fabrics are impregnated with a PVA-FR mixture using a belt press. The entire procedure takes about five minutes, including heating and cooling the composites.

Development
In developing these products over time, Jiva has worked with 50 OEM customers focused on board processing and performance for: 

• Notebook computing 
• Domestic appliances 
• Kitchen appliances 
• White goods 
• LED lighting 
• FR-4 process compatibility 
• Disposable electronics 
• Additive manufacturing

The presentation highlighted four OEM product case studies using two suppliers of Soluboard laminates to three PCB fabricators. 

Technical Datasheet

Summary
Eventually, we will always need a suitable biodegradable copper-clad laminate. I am particularly concerned about the trend of disposable electronics, especially in the growing market of medical sensors and advertising. Much work is being done to make paper more suitable for these applications but if rigidity is required, then we only have paper-phenolic, CEM-1, CEM-3 and FR-2. Disposable electronics are not segregated and enter normal trash bins. I do not know the costs of this laminate, but volume will lower the cost over time, and copper will become the dominating factor. My bet is on additive manufacturing and the development of carbon-nanotube metallization. 

The fact that the material’s manufacturing is continuous-conveyor and not batch-panel provides opportunities for high-frequency application, coupled with its lower dielectric constant, CTE, and that it is 37% lighter than FR-4. It has a lower Tg and Td, but newer plasma conformal coatings may nullify that feature.

More details of the performance, reliability, and decomposition kinetics can be found in a presentation from the 2025 EIPC Summer Conference in Scotland.  Jiva had a booth at IPC APEX EXPO 2025, and should be returning in 2026. 

References

1. PwC’s Second Annual State of Decarbonization—Sector Insights, May 20, 2025.

Happy Holden has worked in printed circuit technology since 1970 with Hewlett-Packard, NanYa Westwood, Merix, Foxconn, and Gentex. He is currently a contributing technical editor with I-Connect007, and the author of Automation and Advanced Procedures in PCB Fabrication, and 24 Essential Skills for Engineers. 

This column originally appeared in the July 2025 issue of PCB007 Magazine.