Growing Sustainability Efforts in Semiconductors Around Chemicals

Companies and countries are working hard to reach net-zero emissions by 2050 and keep global warming to no more than 1.5°C, as stated in the 2015 Paris Agreement. To achieve this goal, efforts must reduce emissions by 45% to 50% by 2030. Alongside the energy sector, which is the source of around three-quarters of greenhouse gas emissions today and holds the key to averting the worst effects of climate change, is the semiconductor industry.  

According to the Boston Consulting Group research, the growing demand for semiconductors over the past few decades has increased the industry’s CO₂ output. Similarly, the method of producing more advanced semiconductors is far more carbon intensive. Manufacturing more advanced semiconductors requires more complex processes, which consume more electricity, water, and process gases.

The Boston Consulting Group states, “If the current growth path were to continue unchecked, carbon emissions from semiconductor production would rise by about 8% annually in coming years and not peak until about 2045.”  

As of November 2023, the semiconductor industry’s total global carbon emissions contribute 0.3%. While not a drastic number, if it remains unchecked, it will grow annually at a meteoric rate for the next two decades.  

The semiconductor industry is aware of its carbon footprint. Over the last several years it has been working to identify the source of its emissions to better limit them. As the Boston Consulting Group found, “Semiconductor devices manufactured in 2021 will have a lifetime CO2e footprint of nearly 500 megatonnes (Mt)—15% from materials and equipment (Scope 3 upstream), 20% from device design and manufacturing (Scopes 1 and 2), and 65% from device processing, use, and disposal (Scope 3 downstream).”

To limit these effects, the semiconductor industry has set robust goals for restricting Scope 1 and 2 emissions, which companies have the most direct control over. Scopes 1 and 2 emissions mainly relate to manufacturing, from water etching to purchased electricity to power processes. Around 65% of semiconductor emissions originate from Scope 1 and 2. The remaining originate from Scope 3, upstream and downstream, which are the emissions companies produce that either create the materials needed for semiconductor production or use the products semiconductors are in.

Original component manufacturers (OCMs) are forming partnerships with their product suppliers to control upstream emissions better. By prioritizing suppliers with sustainable practices, OCMs can help push other suppliers to adopt greener practices to remain competitive.

However, there is a lot of work to be done. The semiconductor industry has a toxic history that goes beyond carbon emissions it is still trying to clean up. The biggest challenge is the industry’s dependence on hazardous chemicals to make the chips we all need.

The Checkered Past of Semiconductors and Chemicals

During the 1970s through the 1990s, when the United States was still a leading producer of semiconductors, the ugly side of fabrication plants was not well known. During the heyday of U.S. semiconductor production, Silicon Valley, littered with numerous fabs, became the host of Superfund sites.  

These sites are “so contaminated that the federal government has put them on a National Priorities List for cleanup. At a site where Intel made semiconductors between 1968 and 1981, for example, the Environmental Protection Agency (EPA) lists more than a dozen different “contaminants of concern,” including arsenic, chloroform, and lead in groundwater.”

“The agency has been working to clean up the groundwater since 1982, and the work will still take “many decades” to get to safe levels of trichloroethene (TCE), a known carcinogen,” stated in the Verge article, “The Fight to Clean Up the Toxic Legacy of Semiconductors.”

Through combined efforts, studies and concerns about using dangerous chemicals in semiconductor manufacturing came to light in the 1990s. By 1992, three separate industry-backed studies uncovered an increased rate of reproductive harm among clean-room workers that was traced back to the use of ethylene glycol ethers (EGEs) used in the photoresist substances that coat semiconductors.

Later, an article in the journal Environmental Health Perspectives “named 10 “chemicals of concern in the semiconductor industry” that include known carcinogens and other substances tied to reproductive health problems, like arsenic, lead, and TCE.”

Lawsuits followed, but after the flurry of studies, semiconductor manufacturers looked hard for substitutes to replace the offensive chemicals used in their process. The semiconductor industry is known for its responsible chemical management programs and risk mitigation measures to ensure safe use and effective management of chemicals.

The industry takes a proactive and collaborative approach to environmental, safety, and health (ESH) issues. This is one reason semiconductor giants have aggressively pursued net-zero emission goals by 2050. Intel, one industry leader with several facilities on the National Priorities List, has been able to remove three of its fabs from the list by fighting to clean up the contamination it left behind.

Despite these improvements, some dangerous chemicals phased out in some countries were still used in others years later. The passage of RoHS and REACH has substantially impacted semiconductor manufacturing and helped companies maintain their sustainability goals.

The Basics of RoHS and REACH

It’s not uncommon to see a global supplier or distributor of electronic components have RoHS or REACH documentation alongside part offers. Both RoHS and REACH regulations apply to businesses that sell products, subassemblies, or components directly or indirectly to countries within the European Union and other countries.  

RoHS and REACH both involve restricting certain chemicals and heavy metals but are slightly different in their enforcement and use.

RoHS stands for Restriction of Hazardous Substances and applies to banned substances in electrical/electronic equipment such as wiring, components, circuit boards, displays, and/or sub-assemblies. REACH stands for registration, evaluation, authorization, and restriction of chemicals and controls all substances that might be used to manufacture the product, including enclosures, brackets, coatings, paints, solvents, and chemicals used during manufacturing.

Both regulations have governing bodies that hold manufacturers accountable for producing high-quality products while being conscious of their effects on the environment.  

Under RoHS the following heavy metals and chemicals are banned: lead, cadmium, mercury, hexavalent chromium, polybrominated biphenyls (PBB) and polybrominated diphenyl ethers (PBDE), bis(2-ethylhexyl) phthalate (DEHP), butyl benzyl phthalate (BBP), dibutyl phthalate (DBP) and diisobutyl phthalate (DIBP).

REACH is a more general regulation. Under REACH, the ECHA (European Chemicals Agency) monitors and deals with 197 substances of very high concern (SVHC). For a chemical or substance to be classified as SVHC, it must meet one or more of the listed criteria:  

• Class 1 or 2 carcinogen, mutagen, or toxic for reproduction (CMR)
• A substance that is PBT (persistent, bio-accumulative, and toxic) or vPvB (very persistent and very bio-accumulative)
• Other substances for which there is evidence of an equivalent degree of concern (for example, endocrine disruptors)

Since its passage, the number of substances listed under REACH has grown, on average, by 35 a year. The number is not so startling when considering the chemicals still necessary for producing microelectronics. Cleaning and etching wafers require a minimum of 11 toxic chemicals. Thanks to their electrical properties, some of these metals are cornerstone elements within specific chips.

For example, it can be hard to substitute gallium arsenide in GaAs chips, which act as the central element in the technology itself. Gallium arsenide even offers benefits over traditional silicon, making it a contender for the next generation of semiconductors.  

In the United States, the Occupational Safety and Health Administration (OSHA) defines workplace exposure limits when working with toxic chemicals. However, there is concern that even post-production finished semiconductor products, such as solar panels, can still release harmful nanoparticles of these components into the environment or the human body.  

What are semiconductor manufacturing companies supposed to do when trying to remain competitive while abiding by ESH regulations? As one of the most innovative industries, companies are constantly looking for safer alternatives or new ways to limit the effects of toxic chemicals.

How to Ensure Environmental and Human Safety in Semiconductor Manufacturing

Just as OCMs work to reduce their carbon footprint, many are also pushing for new avenues of sustainability and safety in the chemicals critical to semiconductor manufacturing. Research teams are constantly looking for new semiconductor materials that offer greater benefits over silicon and are less toxic to produce.  

Japan’s National Institute for Materials Science and the Tokyo Institute of Technology pioneered the study of Ca3SiO, a semiconductor compound comprising calcium, silicon, and oxygen. Ca3SiO is part of a compound group called oxysilicides that cannot emit infrared radiation. These emerging chips may help power fiber-optic communications, night-vision devices, and solar panels.  

Non-toxic semiconductor materials can provide a dual benefit by posing less risk to human health during assembly or repair and being less likely to leach heavy metals into groundwater when they become e-waste. Likewise, the eco-friendlier the materials, the easier it is to discard them back into the environment.  

Unfortunately, non-toxic alternatives aren’t as commercially viable as their counterparts. More research is needed to overthrow to replace the toxic chemicals critical to manufacturing. Sustainability efforts are ramping up thanks to government bodies passing new regulations prioritizing ESH issues, but in the meantime, what can organizations do to practice ESH compliance?

The first and simplest step is to procure components from suppliers and distributors with comprehensive REACH and RoHS compliance documentation. Companies that sell globally must abide by these rules due to the likelihood of selling to countries or states with REACH and RoHS regulatory bodies, such as the European Union. These companies must follow the restrictions set forth and either have special clearance to use or not use banned chemicals.

Prioritize suppliers and distributors that are transparent about their environmental sustainability efforts alongside the chemicals they use during manufacturing. Suppliers that still use toxic chemicals within semiconductor production, and there are many, should be upfront with their efforts to restrict human exposure to harmful chemicals following their country’s regulations.

Another often overlooked way to ensure safety and compliance is through education. This is key for both semiconductor companies and environmental regulatory groups concerned with the use of chemicals. The ongoing debate between the EPA and semiconductor organizations on using per- and poly-fluoroalkyl substances (PFAS) demonstrates this.  

The global association SEMI has opposed country bans on PFAS, claiming that "If all PFAS low volume exemptions (LVEs) substances were eliminated from commerce, this would result in a complete shutdown of all US domestic semiconductor manufacturing operations."  

With the dependence on PFAS in semiconductor manufacturing, SEMI’s warning could become reality if such a ban occurred today. However, this does not mean that the industry should be given a pass. Instead, the semiconductor sector should work to identify processes or alternative technologies that can limit the use of PFAS during production while investing in safer substitutes.  

Through education, other companies and research firms can become more aware of the issue and work towards safer options. This means promoting collaboration among other OCMs and research firms to find new substance alternatives or technology that limits its use.

Sourcengine Has Compliance Information on Components Available for Users

It is critical to have specific documentation to ensure you are procuring parts that follow compliance guidelines set forth by regulatory bodies. When buying from smaller suppliers, it can be difficult to trace this information, especially if they are not certified distributors that must abide by regulations that promote transparency and comprehensive documentation of processes.

Sourceability’s global e-commerce site for electronic component purchasing, Sourcengine, has compliance data on components sold, making it easy for buyers to quickly assess prospective parts. Sourcengine partners with franchised, authorized, and qualified third parties to deliver hard-to-find electronic components to buyers.  

Sourceability is committed to environmental sustainability without sacrificing authenticity. If you need help discovering components that follow your country’s compliance regulations, our team will help source the perfect match. Ready to get started? Contact our team of experts now.