Silicon Carbide's Impact on Electrification

John Palmour, CTO, Wolfspeed, A Cree Company


How the semiconductors of the future are improving performance in the auto industry and beyond.

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Figure 1. Cree employees in the lab

The upcoming shift from silicon to silicon carbide in numerous power systems is the biggest transition in the power semiconductor industry since the move from bipolar to IGBTs in the 1980s. While that shift is occurring, many of the industries impacted are experiencing unusually transformative periods across the board. From the auto industry to solar power, the advantages of silicon carbide have become too great to ignore and all the major players are moving to further integrate it into their technologies as they experience monumental change.

The auto industry represents a prime example of an industry undergoing unprecedented change in the modern era, as it moves from internal combustion engines to electrification over the next decade. The shift from silicon to silicon carbide plays a major role in enabling the efficiencies that are helping EVs meet the demands of consumers while addressing government regulations aimed at impacting climate change. Silicon carbide solutions are helping EVs “go the extra mile” and improve applications in fast-charging infrastructure, drive inverters and power supplies, in addition to facilitating advancements in telecommunications, military, and aerospace applications.

The EV opportunity  

With rising consumer demand and increased government regulation, automakers like Tesla, Ford, and Volkswagen have announced more than $300 billion in EV investments over the next decade. As analysts expect battery electric vehicles (BEVs) to be 15% of total vehicles by 2030, the market for silicon carbide EV components will grow exponentially in the coming years.

With so much emphasis being put on electrification, manufacturers have been unable to ignore the benefits of silicon carbide. It improves battery range, performance, and charge times compared to silicon technologies that have traditionally powered EVs. As a result, many suppliers are announcing EV initiatives with Cree. For example, Delphi Technologies is leveraging silicon carbide semiconductors to enable more efficient, smaller, and lighter inverter systems, while ZF Group is creating full electric drivetrains. ABB is developing and delivering a variety of power systems using silicon carbide.

A boost in efficiency

Silicon carbide has much lower switching losses than silicon IGBTs. Because silicon carbide devices also have no built-in voltage, their conduction losses are significantly lower as well. All of this allows silicon carbide to offer higher power density, lower weight, and higher frequency operation. In a recent automotive test, Cree’s silicon carbide technology reduced inverter losses by approximately 78% compared to silicon.

In an automotive context, these efficiency gains can be put to use in powertrain solutions, power converters, off-board and on-board chargers. Compared to traditional silicon solutions, this can lead to overall efficiency gains of 5% to 10% that manufacturers can use to increase range or decrease the number of heavy, expensive batteries used. Silicon carbide simultaneously reduces cooling requirements, saves space, and weighs less than its silicon counterparts. It’s also enabling fast chargers that can currently add 75 miles of range in about five minutes.

Further increasing adoption rates is the continual decline of the cost of silicon carbide solutions. Keeping with the automotive example, we estimate that an electric car will contain $250 - $500 worth of silicon carbide components, depending on its power needs. Thanks to savings from the battery cost, battery and inverter space and weight, and cooling requirements, auto manufacturers can see an aggregate cost savings of up to $2,000 per EV. While many factors are contributing to the silicon to silicon carbide transformation, this one is key.

Beyond the auto industry

While the auto industry accounts for roughly half of Cree’s $9 billion opportunity pipeline in silicon carbide, solar power, aerospace and defense, and communication infrastructure are few of the other top drivers of demand. Canaccord Genuity recently estimated that silicon carbide demand will exceed $20 billion by 2030.

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Figure 2. Cree’s 650V MOSFET.

Silicon carbide power devices are also allowing industrial and energy businesses to make the most out of every kilowatt hour of electricity and every square meter of floor space. By enabling high frequency industrial power supplies and uninterruptible power supplies that have higher efficiency and power density with lighter weight, the benefits of silicon carbide far outweigh the costs in this arena where greater efficiencies equal greater profits.

In power electronics, silicon carbide is far more efficient than silicon and offers three times the power density, making high-voltage systems lighter, smaller, more efficient, and less expensive. This superior performance has reached a tipping point where it can no longer be overlooked by manufacturers that want to remain competitive in the current marketplace.

The future of semiconductors

While cost was previously a primary barrier to silicon carbide adoption, it continues to decline thanks to growing volume and experience, which has resulted in more efficient, streamlined manufacturing. More importantly, customers are realizing that the true value of silicon carbide shows itself at the system level, not in a component to component comparison. Still, pricing will continue to decrease with further advancements in manufacturing and the increased volume of production needed to meet the demands of multiple industries. To provide a frame of reference, Cree is investing $720 million to meet that demand, including a state-of-the-art, automotive-qualified facility in New York that will increase production capacity by over 30 times our level in 2017.

It’s no longer a question of if or when, we are in the midst of the transformation from silicon to silicon carbide and it’s an exciting time to be participating in so many industries experiencing massive changes across the board. The future of those industries is by no means set in stone, but we’re sure to continue seeing unprecedented change and the manufacturers that can adapt to those changes quickly are sure to reap the rewards.