Bosch begins silicon carbide sample production at Roseville, its first US chip fab

Bosch has begun sample production of silicon carbide (SiC) chips at its plant in Roseville, California, the company’s first semiconductor production site in the US. The site is being converted from an existing wafer fab, and Bosch is investing up to $2 billion in it, supported in part by federal CHIPS funding.

Bosch announced its intention to buy the assets of the Roseville wafer fab in April 2023 and closed the acquisition that August, keeping the site’s staff on through the transition. It has since added cleanroom space and a manufacturing line for SiC.

The site employs more than 300 people and has about 40 years of experience producing semiconductors for automotive and industrial applications, which Bosch says is what let it reach sample production quickly.

“The start of sample production and our agreement with the Department of Commerce is a milestone in providing our local customers with what they have requested: localized US-based manufacturing,” said Paul Thomas, President and CEO of Bosch in North America.

Silicon carbide handles higher voltages, higher junction temperatures and faster switching than silicon. In a traction inverter, this translates to lower switching losses and smaller magnetics and cooling hardware. This is why SiC is used in high-voltage EV powertrains and DC fast chargers.

Bosch has shipped more than 60 million SiC chips since the first generation entered production in 2021. The third generation, which the company says delivers up to 20% higher performance and is smaller than the previous generation, will be built at Roseville, and Bosch says the plant’s first commercial chips, produced on 200 mm wafers, will follow in 2026.

Source: Bosch