Prospects and challenges of SiC in the energy market

Article By : Saumitra Jagdale

High efficiency and chemically inert nature cemented value of Silicon Carbide in power electronics sphere, leading to boom in its utilization.

While silicon has been the go-to semiconductor material for the devices used in power-electronic converters worldwide for quite some time, the invention of silicon carbide in 1891 brought about an alternative to alleviate the dependency on silicon. SiC is a wide-bandgap semiconductor: The energy required to excite an electron into the conduction band is higher, and this wide bandgap has multiple advantages compared with standard silicon-based devices.

A higher bandgap helps ensure higher temperature ranges of operation without breakdown and decreased efficiency, and it has higher efficiency in normal conditions due to lower leakage current. This combined with its chemically inert nature has further cemented the value of SiC in the power-electronics sphere, leading to a boom in its utilization.

Many companies are already at the forefront of this technology, such as Rohm, Infineon, Wolfspeed, and Qorvo. The presidents and managing directors of these companies sat down for a panel discussion on the prospects and challenges of SiC in the energy markets at this year’s PowerUP Expo, moderated by Maurizio Di Paolo Emilio, editor-in-chief of EEWeb and Power Electronics News and editor for EE Times. The panel consisted of Jay Barrus, president of ROHM Semiconductor USA; Chris Dries, general manager of Qorvo Power Device Solutions; Peter Friedrichs, vice president of SiC at Infineon Technologies; John Perry, vice president and general manager of Discrete Power Devices at Wolfspeed; Rob Rhoades, co-founder and president of X-Trinsic; and Steven Shackell, director of Power Semiconductor Global Supplier Marketing at Arrow Electronics.

The panelists introduced themselves and gave a little background on their respective companies, including recent developments and future visions. The companies find themselves at a very interesting position of ever-increasing demand, and their focus has been to cater to this demand while maintaining the quality of products for which each of them are known. They offer unique products and services, with each of them focusing on the various verticals where these SiC-based devices find applications. For example, Qorvo has been focusing more on the automotive industry and its components like on-board chargers and the IT industry concerning power-factor correction and DC/DC converters.

Infineon has been focusing on the deployment of these devices throughout the power system, i.e., generation, transmission, and consumption. Apart from the wide variety of industries in which these companies operate, they are also varied in their experience in the market, with Rohm being the oldest and X-Trinsic being the newest company represented in the panel.

Silicon Carbide Semiconductor

The panelists agreed that one important aspect of this increased demand is the rapid electrification being witnessed all over the world, especially in the automotive sector. Various aspects of the electric vehicle, from on-board chargers to traction inverters to external charging stations, are direct applications for SiC wafers and have contributed to the growth of this demand. Rohm’s Barrus mentioned that this industry is projected to grow from $2 billion in 2024 to $3.5 billion in 2025 and then slowly grow to $6 billion in 2030, which the panelists agreed is a rather modest projection for the growth that they are witnessing right now. To provide more services to customers, Rohm is shifting its focus to manufacturing bigger, 8-inch wafers that opens up more capacity to the customers, which is in demand these days.

According to X-Trinsic’s Rhoades, the satisfaction of this demand for 8-inch wafers will further hasten its adoption. The power density of the systems in an EV is an important factor and has contributed to this shift for higher-capacity wafers. Wolfspeed has a new fabrication unit setup in Mohawk Valley, New York, that spans 500,000 square feet and is built to fabricate 8-inch wafers. Although 8-inch wafers offer more capacity, 6-inch wafers are here to stay, as they still find a wide range of applications, especially in the automotive sector, said Qorvo’s Dries, whose sentiment was echoed by Infineon’s Friedrichs.

Wolfspeed’s Perry, when asked about the recent news about the decreasing cost of the 800-V battery pack, replied that the customers are vouching right now for increased capacity and how the company is taking efforts to increase the capacity of their components is what excites their customers the most. Perry also mentioned that “obviously, over time, the economy of scale, especially the automotive industry, is going to give us huge economies of scale from new traction inverters, and the cost will come down.”

Silicon Carbide Applications in Industry

With regard to the challenges faced by the companies right now, a major part is contributed by the increasing demand. This puts a lot of pressure on the supply chain, as it is not only necessary to design quality products but to ensure that enough products exist to be delivered to the customers. In Perry’s words, the challenge is to “get the quality and the economics and to be able to do it at scale.” The very transition from 6- to 8-inch wafers is a challenge in itself that will push the capabilities of the companies to the edge. The number of wafers per batch will decrease due to geometric constraints, and the cost of the individual wafers are also increasing. This puts a strain on the manufacturing process itself to be able to synthesize these wafers without many losses. An interesting shift is toward single processing compared with the pre-existing batch-processing methods. This method helps limit the number of wafers wasted in case of any event that would otherwise result in waste ranging anywhere between 12 and 28 wafers.

In the future, electrification is expected to continue to grow at a massive scale, and SiC will play a big role soon as more companies understand its advantages and start to transition to it. As for the companies represented in the talk, they are prepared to meet the expected increase in demand and are investing in technologies that will help them scale so that the shift to SiC can happen smoothly and that more people and companies can become a part of it.

This article was originally published on Power Electronics News.

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