COP27 may have ended with few expressing satisfaction at the results, but once again it brought the issue of sustainability back into focus and what industry needs to do to reduce emissions cost-effectively and globally.
According to recent figures the electronics industry accounts for around 4% of global greenhouse gas emissions, and it’s a sector that is seen as requiring substantial innovation if it’s to reduce its environmental footprint. The impact of manufacturing printed circuit boards (PCBs) and integrated circuits (ICs) is immense but that could be reduced through the innovative use of materials and processing methods – such as implementing low-temperature processing, eliminating superfluous wasteful steps, recycling and re-using materials. Research from IDTechEx suggests that within a decade, 20% of PCBs could be manufactured using more sustainable methods such as dry etching and low-temperature solder component attachment.
While most electronics are currently manufactured on rigid substrates demand for flexible electronics is set to rise and the flexible PCB substrate market is forecast to be worth $1.2 billion by 2033. Currently, polyimide is used in flexible electronics, and this is environmentally unfriendly. Consequently, there is a move towards using polyethylene terephthalate (PET) and biodegradable materials such as paper and natural fibres. Microsoft and Dell are among a number of technology companies who investigating the use of biodegradable PCBs.
Next generation of electronics tend to depend upon innovation and this can be liberating as traditional processes often have to be replaced by new techniques that can save time, reduce waste, and cut emissions. These may involve something relatively simple such as switching to a low-temperature solder, or something more revolutionary such as adopting a partial or fully additive manufacturing approach.
At this year’s electronica, Winbond Electronics said that its Flash Memory products would now support the low temperature soldering (LTS) process, reducing the Surface Mount Technology (SMT) temperature from 220~260C in the lead-free process to ~190C.
This will enable Winbond to significantly reduce CO2 emissions in SMT production lines, while also simplifying, shortening and lowering the cost of the SMT process.
According to the forecast of the International Electronics Manufacturing Initiative (iNEMI), the market share of LTS application products is et to increase from ~1% to more than 20% by 2027, delivering significant environmental benefits and more sustainable development practices.
Some of the key benefits of moving to an LTS process include a reduction in carbon emissions as well as significant cost reductions – as the soldering temperature drops, lower-cost low-temperature materials can be used.
Semiconductor manufacturing
A recent report from McKinsey & Company – ‘Keeping the semiconductor industry on the path to net zero’ – has looked at how semiconductor companies are addressing the issue of sustainability.
According to the report, many end customers are already asking suppliers, including semiconductor companies, to step up their efforts to reduce greenhouse-gas (GHG) emissions to achieve net-zero carbon emissions along their entire supply chain.
This push for greater sustainability, however, comes as semiconductor production is having to ramp up to meet increased demand for more sophisticated chip designs used in leading-edge mobility, computing, and connectivity applications.
As production increases, so do emissions and the industry is not on track to limit emissions to the extent required under the 2016 Paris Agreement, which aims to restrict the mean rise in global temperature to 1.5°C from preindustrial levels.
Some semiconductor companies have set aspirational emissions-reductions targets but getting the industry to net zero will require more comprehensive action, according to Peter Spiller, partner at McKinsey & Company.
“We’ve seen several big tech companies announcing ambitious targets to become net zero or carbon neutral by 2050 or even 2030. It is, however, extremely difficult to meet these goals while upstream suppliers of tech companies – including the semiconductor industry – are lagging behind. As our report showed, upstream suppliers of tech enterprises need to make a greater investment into decarbonisation to keep up.”
According to the report, emissions from semiconductor device makers fall into different categories: those that arise directly from fabs, primarily from process gases with high global warming potential (GWP) that are used during wafer etching, chamber cleaning, and other tasks; others come from high-GWP heat-transfer fluids that may leak into the atmosphere when fabs use them in chillers.
Secondly, emissions that arise directly from purchased electricity, steam, heating, and cooling equipment; and, finally, upstream emissions that are generated by suppliers or their products, while downstream emissions are related to the usage of products containing semiconductors.
What is clear is that the steps that semiconductor companies are now taking will not be enough to get the industry on a 1.5°C trajectory by 2030 and, in fact, emissions may rise significantly above current levels as semiconductor production volume increases.
Among a range of scenarios put forward by McKinsey are a pessimistic scenario, without significant action, carbon dioxide equivalent (CO2e) would increase from 93 million tons in 2020 to 183 million tons by 2030. If companies step up their decarbonisation efforts as announced, then emissions increase at a slower rate and could reach 116 million tons by 2030.
In its most ambitious scenario, emissions are at 54 million tons that year lower than the levels recorded in 2020.
But to get on a net-zero trajectory by 2030 there needs to be a co-ordinated effort across industry with the development and adoption of new technologies.
“The semiconductor sector needs to double down on innovation to reach its net zero goals by 2050. And there is a great potential to accomplish that if all semiconductor organisations showed a willingness to experiment, encouraged collaboration with other industry companies, e.g., through the newly formed Semiconductor Climate Consortium, and developed effective decarbonisation technologies,” said Spiller, who suggested the installation of gas-abatement systems as a possible solution.
Every semiconductor company will need to adopt a more proactive and innovative approach - making a greater investment in decarbonisation and showing a willingness to experiment – and work with leading start-ups and academic labs. Innovation will involve taking risks, however, since not every idea will lead to real solutions that meaningfully reduce emissions.
Recycling and e-waste
When it comes to sustainability while more environmentally-friendly forms of production are critical there is also the issue of recycling and the better management of e-waste.
According to Peter Keeley-Lopez, Senior Process Applications Engineer at Tetronics, “Every day, vast volumes of critical resources are thrown away. Inefficient waste management, consumer behaviour and a lack of awareness means that some critical materials only have a single-use life, when they could be recovered, and their value put back into the economy.”
According to figures from the World Economic Forum just 20 per cent of global e-waste is recycled, while the other 80 per cent ends up in landfill or is incinerated.
“Among this waste is a significant amount of gold, silver, platinum and lithium that are widely used in PCs, laptops, mobile phones and batteries,” said Keeley-Lopez. “But not everything is thrown away. Many of us hold on to our devices so there is what is being called ‘urban mines’ in homes across the UK, for example, that could contain around 50 times the concentration of critical metals than original sources.”
The UK government has recognised the value of urban mining and in July 2022 launched a Policy Paper, Resilience for the future: The UK’s critical minerals strategy calling for the acceleration in the recovery, recycling and reuse of critical minerals and components to alleviate pressure on primary sources.
Ironically, an unintended consequence of the Net Zero drive towards a safer, sustainable planet is an increase in demand for critical materials like lithium, nickel, cobalt, manganese and graphite, that are essential for the batteries and permanent magnets used in wind turbines and electric vehicles.
Relying on primary sources to extract the volume of materials needed to achieve the energy transition is going to be problematic. Critical materials are typically mined from a small number of countries or sites and the current energy crisis has shown that it is unwise to rely heavily on resources from a single supplier.
Critical minerals are also expensive to extract from primary sources and may come with a high human or ethical price tag.
“They involve processing large volumes of extraneous ore to achieve a relatively small amount of the required materials, compared to the concentration of materials in devices that are no longer in use,” said Keeley-Lopez.
While there is a great deal of critical material in circulation that is embedded in equipment and products that are reaching the end of their initial use, the materials themselves still have a lot of life in them, and their disposal in landfill can be hazardous. It makes economic and environmental sense to recover materials from end-of-life products, like batteries and printed circuit boards (PCBs).
While the focus is on electronic components, batteries, from consumer devices up to electric vehicles, and catalytic converters on cars that can all be recovered and reused so too could industrial catalysts, solar panels, turbines and generators.
“There is a way to extract critical materials from spent devices and equipment, prevent hazardous waste reaching landfill, and create a beneficial by-product,” explained Keeley-Lopez. “Just as critical materials are initially mined from the earth, recovering materials from waste is a process. Critical materials tend to concentrated in the remaining Printed Circuit Boards (PCBs) and can go through a controlled process where plasma technology is applied and the precious metals are recovered. Any spent materials are converted into substances that are benign to the environment.”
Plasma is an electrically charged – or ionised – gas and occurs naturally in the environment and is used in television and display screens, fluorescent lighting and even arc welding.
Tetronics uses plasma technology to recover precious metals as well as to remove the toxicity of industrial materials like asbestos and air pollution control residues.
To recover critical metals from electronic equipment, Tetronics’ process involves introducing the materials into a sealed furnace and using a plasma arc to apply intense heat and ultra-violet light in a controlled environment.
“The chemistry separates and recovers the valuable metals, minerals and other materials from the feedstock. The process also destroys any hazardous elements and leaves behind a non-hazardous glass-like material called Plasmarok. Nothing is wasted,” explained Keeley-Lopez.
So much is discussed and debated around more sustainable forms of manufacturing, as described in the MnKinsey report earlier, as well as the need for more recycling and recovery of e-waste in general.
It is certainly possible to create a more sustainable electronics industry and one that reduces the exploitation of people in poorer economies who are used to source or recover materials in often uncontrolled ways.
The question is will industry, investors and consumers be willing to adapt, properly engage with the issue of sustainability and, ultimately, pay more for the devices that have become part of every-day life?
