From decarbonization to digitalization and electrification, power semiconductors are playing a key role in fighting climate change and driving adoption of electric vehicles (EVs) around the world. And this trend was evident at the recent PCIM Europe, which was held in Nuremberg, Germany from 11 -13 June 2024. Power semiconductor manufacturers, both well-known and startups, came here to display their leading-edge products and technologies, to address a wide range of emerging needs and set the momentum going. While business and marketing analysts projected roadmaps for wide bandgap (WBG) and silicon (Si) power devices to give the attendees a vision of the emerging markets for these devices for next several years.
France based analyst Yole Group, for example, projected significant opportunities for silicon carbide (SiC) power devices in the emerging battery electric vehicles (BEVs) market as the adoption grows worldwide. With the strong push for BEVs in the past few years, power SiC has become the fastest growing semiconductor market, according to Yole. “Record BEV shipments in 2023 from Tesla, BYD, Hyundai, and others are reshaping the supply chain landscape, stated Yole. According to the firm’s latest forecast, the power SiC device market will exceed US$10B by the end of this decade (Figure 1). Major suppliers have been increasing capacity at all levels of the supply chain to mitigate the supply constraint concerns of the past years. Multiple investment projects are rolling out globally, and the market is preparing for higher production volumes. This has also opened the window for power SiC to move into many industrial applications, such as EV chargers and renewable energy.
FIG 1 Power SiC market by application. Source: Yole Intelligence 2023
Increasing SiC Capacity
Speaking of capacity, key players like Wolfspeed, STMicroelectronics, Infineon Technologies, Navitas Semiconductor, onsemi, and few others announced plans to increase capacity, while inking partnerships to ensure long-term supply of SiC devices. In addition, makers like Vishay Intertechnology, Alpha & Omega Semiconductor (AOS) and Qorvo unveiled brand new SiC MOSFETs for EVs and other industrial applications. While SemiQ released a 1700 V SiC Schottky discrete diodes in both bare die and TO-247-2L package with maximum forward currents of 110 A and 151 A, respectively.
STMicrolelctronics, for example, announced a new high-volume 200-mm SiC manufacturing facility for power devices and modules, as well as test and packaging, to be built in Catania, Italy. Combined with the SiC substrate manufacturing facility being readied on the same site, these facilities will form STMicroelectronics’ SiC campus, realizing the company’s vision of a fully vertically integrated manufacturing facility for the mass production of SiC on one site. According to STMicroelectronics, the creation of the new SiC facility is a key milestone to support customers for SiC devices across automotive, industrial and cloud infrastructure applications, as they transition to electrification and seek higher efficiency. “The scale and synergies offered by this project will enable us to better innovate with high-volume manufacturing capacity, to the benefit of our European and global customers as they transition to electrification and seek more energy efficient solutions to meet their decarbonization goals,” said Jean-Marc Chery, president and chief executive officer (CEO) of STMicroelectronics.
Additionally, to further extend their existing cooperation on SiC devices, STMicroelectronics and China’s leading automobile and new energy vehicle (NEV) manufacturer Geely Auto Group announced a long-term SiC supply agreement. Under the terms of this multi-year contract, STMicroelectronics will provide multiple Geely Auto brands with SiC power devices for mid-to-high-end BEVs, boosting Geely Auto’s NEV transformation strategy with improved performance, faster charging speeds and extended driving range. Plus, building on their longstanding cooperation across multiple automotive applications, Geely and STMicroelectronics have established a joint lab to exchange information and explore innovative solutions related to automotive electronics/electrical architectures (i.e. in-vehicle infotainment, smart cockpit systems), advanced driver assistance (ADAS), and NEVs.
In a statement, Geely Auto said that it has adopted STMicroelectronics’ third generation SiC MOSFETs in electric traction inverters. “The traction inverter is the core of electric powertrains and SiC MOSFETs maximize their efficiency,” stated the manufacturer.
Likewise, to address the increasing SiC demand, leading supplier Wolfspeed continues to ramp production in its first and largest 200-mm SiC power fab in Marcy, NY, USA, which is expected to be 20% utilized by July 2024. Similarly, efforts are underway to build a highly-automated, cutting-edge 200-mm wafer fabrication facility in Saarland, Germany to serve a wide variety of European automotive, industrial and energy applications.
Early this year, to meet the growing global demand for SiC devices, Germany’s Infineon Technologies expanded and extended its existing long-term 150-mm SiC wafer supply agreement with Wolfspeed, which was originally signed in February 2018. Concurrently, the company has also completed the first phase of construction of its 200-mm wafer fab in Kulim, Malaysia. Scheduled for official commissioning in August, the Kulim 3 wafer fab module is poised to commence SiC production by the end of 2024, said Infineon in a statement.
The SiC Competition Grows
Meanwhile, Vishay Intertechnology, Inc. released a new 1200 V SiC MOSFETs labeled MaxSiC series with on-resistances of 55 mΩ, 95 mΩ, and 280 mΩ in standard packages for industrial applications. Custom products will also be available, according to Vishay. Furthermore, the company unveiled a roadmap for 650 V to 1700 V SiC MOSFETs with on-resistances ranging from 10 mΩ to 1 Ω. According to this announcement, Vishay’s SiC platform is based on proprietary MOSFET technology, which is enabled through the company’s acquisition of MaxPower Semiconductor, Inc. While Alpha & Omega Semiconductor unwrapped new package options for its 1200 V SiC MOSFETs. Besides the D2PAK-7L surface mount package for its 1200 V, 40 mΩ device, the maker also released a 1200 V/10 mΩ half-bridge module with press-fit pins and an integrated thermistor in a module with standard footprint. Similarly, Navitas Semiconductor continues to expand its SiC portfolio with the addition of Gen 3 Fast 650 V and 1200 V SiC MOSFETs. Others in this race include Onsemi and Microchip.
High-Voltage GaN Developments
Presentations from key players like Infineon Technologies, Texas Instruments, Transphorm, Navitas Semiconductor, Power Integrations, GaNPower International, Cambridge GaN Devices (CGD) and other notable GaN suppliers clearly indicated that high-voltage GaN is the future. Advances in GaN-on-Insulator HEMTs and vertical GaN technologies are pushing breakdown voltages beyond 650 V. Transphorm, now part of Renesas, disclosed its 1200 V GaN-on-Sapphire HEMT in a cascode structure, along with a device model for automotive, industrial, datacenter, and renewable energy applications.
Likewise, Power Integrations (PI) discussed its industry-first, high-reliability 1250 V-rated lateral GaN HEMT and its readiness for real-world use at very high input voltage. This was demonstrated by means of a high voltage flyback power supply design using a 1250 V InnoSwitch flyback switcher IC (Figure 2). The 1250 V GaN is a normally-on, depletion mode device built using PowiGaN technology with a proprietary field plate architecture optimized to control peak electric fields across the device. It is connected in series with a low-voltage silicon MOSFET in a cascode configuration to achieve effective normally-off operation, which is essential for safe operation of power electronic systems, according to PI.
FIG 2 Schematic of the power supply design used to evaluate the 1250 V GaN flyback switcher IC. Source: Power Integrations.
Recently, PI inked an agreement to acquire the assets of Ithaca, New York based startup Odyssey Semiconductor Technologies, a developer of vertical GaN transistor technology. The transaction is expected to close this month, after which all key Odyssey employees are expected to join PI. In a statement PI stated, “Our goal is to commercialize a cost-effective high-current and high-voltage GaN technology to support higher-power applications currently served by SiC, at a much lower cost and higher performance enabled by the fundamental material advantages of GaN over SiC. The experience of the Odyssey team in high-current vertical GaN will augment and accelerate these efforts, and we are delighted to add them to our team.”
Similar efforts are underway at Germany’s Fraunhfer IAF, where the researchers are developing novel technologies for lateral and vertical GaN transistors with blocking voltages above 1200 V. Here, scientists are exploring GaN-on-Si HEMTs, GaN-on-insulator HEMTs and vertical GaN HEMTs for high-voltage applications. By continuously optimizing the material and its processing (epitaxy, processing, structuring), researchers at Fraunhofer IAF were able to demonstrate GaN-on-Si HEMTs with static blocking voltages of over 1200 V. In addition, the researchers are exploring highly insulating carrier substrates such as sapphire, to overcome the voltage limit. According to Fraunhofer IAF, “Lateral GaN-on-Sapphire HEMTs can be manufactured cost-effectively based on relevant preliminary work for light-emitting diode applications and can be produced in existing production lines.”
