Chip shortage prompts EV makers to shore up SiC supply

Automotive manufacturers are engaging with silicon carbide (SiC) power device suppliers to secure deliveries as they look to avoid a supply crunch similar to the ongoing global semiconductor shortage.

Electric vehicles (EVs) use a growing number of power management devices, including metal oxide semiconductor field-effect transistors (Mosfets) and insulated gate bipolar transistors (IGBTs). IGBTs are used to switch the current in the drivetrain and Mosfets are used in the drivetrain, battery management system and voltage converters.

Manufacturers are increasingly shifting from using silicon to silicon carbide and in some cases gallium nitride (GaN) in these devices. Prices for SiC devices are higher than for silicon devices, but by operating at higher temperatures and frequencies, they make EV batteries more efficient and reduce overall system costs.

The cost savings are encouraging carmakers to incorporate SiC into new EV designs, according to Gregg Lowe, chief executive at US-based Cree, which produces SiC and GaN power devices. Automotive accounts for around half of the company's $10bn device pipeline, Lowe said.

The production constraints that have resulted from the semiconductor supply shortage have prompted carmakers and original equipment manufacturers (OEMs) to look at their supply chains for other components, including Mosfets and IGBTs.

"The attention the car manufacturers and the Tier 1s have to our supply chain is very high and very acute," Lowe said.

US-based ON Semiconductor similarly noted strong demand for SiC and IGBT products for EVs from Tier 1 and global EV OEMs, a few of which have recently launched new platforms and charging applications. The company is also observing a shift in the way carmakers approach the supply chain.

"The just-in-time era is not going to be sustainable," the company's president, chief executive and director, Hassane El-Khoury, said. "The short-term cancellation, all of that I think is going to be a thing of the past."

German semiconductor manufacturer Infineon Technologies expects its SiC business to double to €170mn in the current fiscal year ending in September, led by growth in automotive demand, having previous expected a 70pc increase.

Capacity expansions accelerate

Companies are increasing their production capacity expansions or bringing forward plant starts to meet the growing demand.

Cree, which launched four new SiC devices in March, is spending $550mn this financial year to expand its production of SIC materials and wafers by 30 times. The investment, part of a five-year $720mn capital expenditure budget, includes the construction of a wafer fabrication plant in New York state in the US, which is scheduled to start operations in 2022. Cree is also expanding capacity at its materials factory in North Carolina.

Cree expects SiC demand to accelerate in 2024 and beyond based on carmakers' production schedules. "We weren't predicting this. But the capacity coming on line and in a relatively short period is certainly a nice light at the end of the tunnel for some of these guys as they start placing bets on silicon carbide," Lowe said.

Infineon is starting to ramp up its manufacturing of silicon carbide products for vehicle inverters. It started installing equipment in a new manufacturing plant in Austria in March, Ploss said. The company is bringing forward the start of production at the plant to the last quarter of the fiscal year ending in September. And it is increasing investments in capacity, having revised them lower in 2019 when demand was weaker.

By Nicole Willing