Silicon carbide semiconductors boast wider bandgaps that enable electrical energy transfer more efficiently than their silicon counterparts, making them suitable for applications like power electronics for electric vehicles and space exploration instruments. This makes silicon carbide particularly suited for use on rovers and probes.
Coherent is establishing a new subsidiary to supply 150 mm and 200 mm silicon carbide (SiC) substrates and epitaxial wafers. Sohail Khan, Executive VP for Wide Bandgap Electronic Technologies at Coherent will lead this new division.
Power Electronics
Silicon carbide chips provide electric vehicles with increased battery power and extended range due to their higher efficiency, meaning less wasted energy as heat. Their thermal resistance also allows designers to build smaller components which save space and costs.
Chip makers are racing to meet demand for this technology by developing production infrastructure for SiC wafers — which are thin slices of semiconductor material with various substances incorporated. However, this race does present several obstacles and challenges, including creating efficient factories with lower production costs.
Wolfspeed, Infineon and SK Hynix have already announced plans to construct new wafer-producing factories capable of meeting the growing demands from electric vehicle (EV) markets – projected to surpass $2 trillion in 2040 – thanks to lucrative opportunities presented by these developments.
Sohail Khan, Coherent’s executive vice president for new ventures and wide bandgap electronics technologies has noted that companies producing power semiconductors for electric vehicles require more reliable silicon carbide wafers in order to manufacture more reliable power semiconductors in these vehicles. To meet this need, Coherent recently created a subsidiary dedicated solely to expanding manufacturing capacity of silicon carbide wafers.
DENSO and Mitsubishi Electric will each invest $500 million for a 12.5% non-controlling ownership stake in Coherent’s newly formed business, providing Coherent with capital to expand production of 200mm silicon carbide (SiC) substrates and epitaxial wafers as well as enter into arm’s-length long-term supply agreements to support Japanese firms’ requirements.
Coherent’s partnership could assist it in rebounding after its recent struggles. First quarter revenue rose slightly but was below recent high points driven by strong sales of optical modules and lasers.
This deal aims to expand Coherent’s silicon carbide business and establish itself as a major supplier of power semiconductors. Khan has stated the importance of having strong lead customers from the start, so chose DENSO and Mitsubishi as customers right from the beginning – they both are top suppliers for automotive power systems who have purchased 150mm SiC substrates from Coherent over time.
RF & Microwave
With the rising popularity of electric vehicles (EV), silicon carbide (SiC) chips have quickly become a focal point among semiconductor companies. SiC is much less costly than traditional silicon chips and can operate at higher temperatures, which allows manufacturers to shrink cooling systems while decreasing weight and cost while increasing power density and shortening production timelines — an important consideration in meeting consumer demand for EVs.
SiC chips have been proven to perform well in laboratory experiments, yet integrating them into circuits can be more complicated due to increased energy requirements and faster heating rates for production requiring specialized materials and processes to ensure they can operate at high speeds without overheating or malfunction.
Coherent (formerly II-VI), in response to these challenges, announced its intention to form a subsidiary dedicated solely to SiC production that will manufacture substrates and epitaxial wafers before working closely with customers throughout each stage of production, from raw material through finished device or module production. Coherent will invest in expanding capacity at manufacturing facilities while improving R&D and services capabilities.
Denso and Mitsubishi Electric of Japan will invest $500 million each, in exchange for 12.5 percent non-controlling ownership interests in their new subsidiary. Furthermore, arm’s length long-term supply agreements will be entered into to meet demand from these Japanese firms for 150mm and 200mm SiC substrates and epitaxial wafers.
Coherent’s collaboration will bring financial benefits as well as innovative technology for the rapidly expanding EV market. One such innovation involves improving spin coherence of silicon carbide color centers via magnetic fields and RF pulses; specifically targeting their 29Si nuclear spins which have long spin coherence times that can be enhanced.
These signals are then reflected back on the same channel and detected at exactly the same time, creating a coherent readout of the ground state and enabling spectrally selective coherent control of qudit modes; Figure S8 illustrates this with respect to 4H-SiC30 states of both PDMR and ODMR modes.
Automoción
Silicon carbide (SiC) offers unique properties for electronic devices operating at high temperatures or voltages, beginning its initial use in 1907 with light-emitting diodes (LEDs) and detectors in radios; today it is preferred in high voltage power switching applications – an SiC MOSFET can switch at more than 100 times the rate of traditional silicon transistors while maintaining comparable temperatures.
Coherent’s expertise in Silicon Carbide Semiconductors is used by customers like Japanese automotive supplier DENSO and Tokyo-based Mitsubishi Electric to support them with automotive applications using SiC, including power electronics for electric vehicles. Together they have invested $1 billion total in Coherent’s Silicon Carbide Semiconductor business.
Coherent will retain 75% ownership and control of this new subsidiary business; while DENSO and Mitsubishi Electric each own 12.5% non-controlling stakes. As per Coherent’s goal to generate future operating and capital expenses independently of Coherent’s other businesses, this business should create its own operating expenses over time.
Customers include some of the world’s top automotive companies. “Ideally,” states Khan as head of his newly formed subsidiary company. The new subsidiary will engage with companies at both substrate/epiwafer level as well as device or module level.
As the automotive world rapidly transitions toward electric vehicles, automotive manufacturers should have access to only the highest-performance and most cost-effective power switching devices available. Coherent silicon carbide power transistors not only offer excellent performance and reliability; they also contribute towards environmental protection by decreasing energy consumption, increasing efficiency and helping expedite the transition towards low carbon societies.
Coherent’s SiC semiconductor products boast industry-leading avalanche ratings and RDS(on) at high temperatures, enabling designers to design power conversion systems with improved efficiencies and reduced operating costs. Furthermore, these SiC products can be manufactured at higher switching frequencies with improved temperature, frequency and voltage capabilities over their silicon counterparts allowing the production of smaller, lighter automotive motors needed to drive the next generation of green cars to market.
Aerospace
SiC has proven itself indispensable to the aerospace industry for various demanding applications, including high-power laser amplifiers, harsh environment sensing, LiDAR systems and sensor arrays. According to Yole Group market research firm’s estimate, SiC market size in space should surpass $21 billion USD by 2027 (Chiu & Dogmus).
Silicon carbide (SiC) has many applications, with extreme environment electronics being one of the more attractive applications for its use. SiC’s key attributes make it ideal for operating in environments such as aircraft engines, satellite navigation systems, radar and communications systems requiring high temperatures and voltages.
But to successfully operate SiC in these extreme conditions requires more than simply an industrial-scale manufacturing process; you require an in-depth knowledge of its molecular-level properties.
Scientists from the University of California, Berkeley have made progress toward their goal. Utilizing high-resolution spectroscopy, they have observed quantum phase transitions in crystalline silicon carbide; their observations may provide clues as to its low temperature behavior of its electronic spin states.
This discovery offers a more complete picture of silicon carbide’s physical behavior than has previously been available, which could assist engineers in designing room-temperature masers and sensitive magnetic field sensors using silicon carbide.
Coherent is applying its insights in its latest project. The company recently established a subsidiary to expand vertically integrated production of SiC substrates, epiwafers, and devices with Denso and Mitsubishi Electric investing a combined total of $1 billion into this venture led by Sohail Khan – executive vice president for Wide Bandgap Electronic Technologies at Coherent.
Two Japanese conglomerates will each invest $500 million into a new subsidiary in exchange for 12.5% non-controlling ownership interest and long-term supply agreements to support its SiC activity, according to Khan. He states this approach gives his team access to maximum customer feedback necessary for success.