Soluble in water, 90% of components can be recycled! Infineon launches biodegradable PCB substrate

According to statistics from the World Economic Forum, more than 54 million tons of discarded electronic devices are generated worldwide each year. The amount of electronic waste generated by these discarded devices is growing at a rate of 2.5 million tons per year, but only 17.4% of the electronic waste is collected, recycled and reused. The circuit boards inside them are usually cut by large shredders, and then processed by magnetism, water washing and incineration to extract specific precious metals and minerals. The circuit boards themselves are made of glass fiber and epoxy resin. These materials are not valuable after being cut, so they are often treated as waste and landfilled, incinerated or piled up. This not only causes a waste of resources, but also pollutes the environment.

To solve this problem, Infineon, Germany's largest semiconductor manufacturer, recently teamed up with British startup Jiva Materials to launch Soluboard, a recyclable and degradable PCB substrate made of natural fibers and halogens.

The halogen-free flame retardant impregnated natural fibers in Soluboard are encapsulated in a non-toxic polymer, which will dissolve when immersed in 90°C hot water for 30 minutes. The dissolved polymer solution can be treated as wastewater normally, the electronic components on the PCB board will be separated, and the remaining natural fibers can be reused as fertilizer.

At the same time, the residual water after dissolving the polymer can be safely treated like ordinary wastewater without causing additional pollution to the environment. In this process, about 90% of the components attached to the circuit board can also be recycled.

Jonathan Swanston, co-founder of Jiva Materials, said that this PCB board using a water-based recycling process can increase the recovery rate of precious metals.

Jiva Materials also said that replacing FR-4 PCB material with Soluboard will save 10.5kg of carbon and 620g of plastic per square meter of PCB.

Infineon has already produced three different PCB demonstration boards based on the Soluboard substrate and plans to gradually expand its product range in the future.

Before soaking

After soaking

“For the first time, recyclable, biodegradable PCB materials are being used in electronic product designs for consumer and industrial applications, which is a milestone towards a green future,” said Andreas Kopp, Head of Product Management Discretes for Green Industrial Power at Infineon Technologies. “We are also actively investigating the reusability of discrete power devices at the end of their useful life, which would be another important step in driving the circular economy in the electronics industry.”

Infineon Technologies AG said it is using the biodegradable material to reduce the carbon footprint of demonstration and evaluation boards, and is also exploring the possibility of using the material in all circuit boards to make the electronics industry more sustainable.

At present, Infineon has produced three different demonstration boards with Soluboard and plans to expand its product range in the coming years. More than 500 devices are already in use, demonstrating the company's power discrete device portfolio, including a board equipped with components specifically for refrigerator applications. Based on the results of the ongoing stress tests, Infineon plans to provide guidance for the reuse and recycling of power semiconductors removed from Soluboard, which can significantly extend the service life of electronic components.

According to Theregister, Peter Wawer, president of Infineon's Green Industrial Power division, said that a small number of selected Soluboard motherboards have been shared with selected customers, and these products will be available through Infineon's established channels from the fourth quarter of 2023.

Although Soluboard claims to reduce carbon emissions by 60% and can be decomposed by hot water, which is very beneficial for the recycling of related components and metals on PCBs, the cost of Soluboard is much higher than that of traditional PCBs, about 50% to 75% higher, at least in the initial stage.

Infineon is actively investigating the reusability of its discrete power devices, as they were not designed with this recycling method in mind.

It is reported that Soluboard has also been used in the United States. Researchers at the University of Washington worked with Microsoft to design an "environmentally friendly mouse" whose core is a circuit board made of Soluboard. The study found that the data transmission performance of the embedded chip is comparable to that of a traditional circuit board. The chips recovered after the circuit board is decomposed can be reused after removing moisture in an oven without performance degradation.

Of course, Soluboard will need more testing in real-world environments before it can be widely adopted, and the electronics recycling industry is a low-margin business and may not get much value from dissolvable circuit boards, but any advance in electronics technology that reduces plastic use and makes it easier to decompose is worth paying attention to.