Catalytic technology removes toxic chemicals from microchip manufacturing wastewater

Semiconductor manufacturing is a fastidiously clean business. Components are washed multiple times to remove impurities, drawing on vast amounts of purified water and other chemicals.

The manufacturing plants use huge amounts of water. For example, the world’s largest semiconductor manufacturer, TSMC, uses three billion metric tons of water per day in their three Taiwanese science parks—three times the daily water supply of Sydney.

Professor Long Nghiem, Director of the UTS Center for Technology in Water and Wastewater, is harnessing the power of chemistry to help the industry recycle more water and move towards a more sustainable future.

“With the booming demand for microchips to power artificial intelligence, and huge volumes of water being used to manufacture them, companies need to recycle at least 90% of their water to not deplete local supplies. More than 100 specialty chemicals are used in microchip manufacturing. We need to remove the worst of these chemicals to get clean water at the end of the process,” he says.

“The two most problematic of these chemicals are hydrogen peroxide, used in surface cleaning, and triazole, for corrosion prevention. Both are very toxic and don’t break down easily.”

Working with water tech start-up Infinite Water International (IWI) Australia, Professor Nghiem and his team, including fellow researcher Associate Professor Cuong Ton-That, have developed a new catalytic technology that breaks down these two main pollutants.

“We use a catalytic process. We don’t filter out the contaminants but instead have an oxidation agent that breaks them down in a very targeted way,” he says.

“We pack this agent into a plug-and-play unit that fits into wastewater infrastructure and flushes contaminated water to clean it. We degrade the pollutants to the point where the water becomes safe for any subsequent processes for recycling or eventual disposal.”

“The current treatment process for making microchips has been around [for] almost 100 years. We’re not trying to change this process, we’re trying to add to and utilize all of the existing infrastructure.”

Two of the world’s largest logic chip makers are working with IWI Australia to evaluate this innovative technology on their wastewater operations.

“Typically, more than 10% of the capital expenditure of these advanced semiconductor manufacturing fabrication plants (or fabs) are for water use and water recycling. This adds up to billions of dollars,” says Matthew Ng, Founder and CEO of IWI Australia.

“We’re looking to help them sustainably recycle water more cost-efficiently at this huge scale. This industrial disruptive innovation can address significant pain points for these companies.”

“Once they can remove specialist chemicals at a much lower cost, it allows them to recycle most of the water and discharge any excess wastewater safely into the environment.”

The technology has been patented for use with hydrogen peroxide, demonstrating its efficient removal of high-concentration peroxide in just a few minutes.

A patent is pending for triazole destruction, where it has been shown to degrade up to 90% of the pollutant in just an hour in an innovative and simple process.