While semiconductor executives lament slow demand and excess inventories, one sector appears to be resilient: silicon carbide power circuits used in electric vehicles.
But companies looking to capitalize on this market could run into complications as they transition to 200 mm wafers, prompting shares of Wolfspeed and STM to fall this week.
Power Semiconductor
Power semiconductor devices are used to control, amplify and switch the flow of electric current in circuits. To accomplish this task, they feature much higher voltage current ratings compared with signal level semiconductor devices and larger p-n junction areas than signal semiconductors.
Power diodes are a subcategory of power semiconductors designed to handle high levels of power. To do this efficiently, they need a wide p-n junction area in order to handle more current. Once solids reach their maximum current density threshold however, their functionality becomes compromised and heat-up too rapidly to remain functional.
As energy efficiency becomes ever more essential, power semiconductors that minimize losses have become increasingly in demand. Silicon carbide and gallium nitride (GaN) have both proven their ability to open up new opportunities within power semiconductor technology.
Metal Oxide Semiconductor Field Effect Transistors (MOSFETs) have become a ubiquitous feature of electronics today, from personal computers and smartphones to electric cars and beyond. MOSFETs serve as semiconductor switches which control electricity flow between electronic signals. Their applications range from controlling flow control systems for video game consoles, phones and cars alike.
GaN and SiC power semiconductor devices outshone traditional silicon MOSFETs when it came to performance over a wider temperature range, offering higher switching speeds with lower conduction losses and switching losses, higher switching speeds with greater switching speeds, higher temperature resistance and less parasitic effects than their silicon-based counterparts.
Power semiconductors offer many advantages for numerous applications, including energy savings and lower costs. You’ll find them in electric vehicles and charging systems, industrial motor drives and industrial motor drives; their presence helps reduce losses on AC motors as well as improving accuracy for power supplies, solar cell arrays and electrical grids.
Power semiconductors are an indispensable component of most renewable energy systems, providing voltage regulation, frequency conversion and DC to AC conversion services, while also helping control electricity flows in power plants.
Автомобили
Silicon Carbide (SiC) is a robust hexagonal chemical compound consisting of silicon and carbon that displays strong covalent bonds to make a long-wearing material with Mohs hardness rating that falls somewhere between that of Alumina (9), and Diamond (10). Due to its low thermal expansion and strength properties, SiC is widely used in industrial ceramics applications, as an abrasive, as well as boasting excellent mechanical properties including wear resistance and high impact toughness – two qualities which have led to widespread commercial use over its predecessors.
Silicon carbide’s hard, abrasive and refractory characteristics have long been recognized, but its semiconductor properties are what is driving its use as one of today’s trendiest materials in power electronics. SiC’s wide band-gap allows devices made with this material to have higher breakdown voltage and lower turn-on resistance compared to silicon-based semiconductors.
SiC’s low internal resistance makes it an invaluable component in power semiconductor applications, helping reduce switching losses by enabling electrons to flow more freely through its devices and thus creating efficient thyristors, IGBTs, MOSFETs etc.
SiC is also an ideal material to use in electric vehicle (EV) inverters, as it can enhance efficiency and increase range by decreasing power management system size while improving power density. According to Goldman Sachs’ estimate, using SiC in inverters could save manufacturers an estimated total of up to $2,000 in manufacturing costs and energy consumption per vehicle.
Silicon carbide production is an intricate process involving various stages from raw materials through finished product production. Starting from natural rock sources, powdered forms of SiC are extracted using either a bauxite crusher or blast furnace and produced into powder form for use as raw material for further processes. The ingot produced is then carefully and meticulously sorted manually by experienced workers to meet customer requirements in terms of purity and quality, with final products available in green or black hues that range between 87-94% purity levels. Elkem’s state-of-the-art silicon carbide facility in Liege, Belgium operates under the name EPS (Elkem Processing Services). This plant supplies high purity raw materials and finished products to multiple industries including iron and steel production, ceramics production, nonferrous metal production, energy, chemicals and automotive applications.
Industrial Motor Drives
Silicon carbide (SiC) is an extremely hard, grey-green material with the chemical formula SiC that ranks as one of the hardest substances known to humans, requiring diamond-tipped blades to cut it. Silicon carbide also acts as a semiconductor material; that means when treated with impurities or doping agents it may display semi-conducting properties which allow current to flow through while not completely blocking it out – an excellent candidate for power semiconductor devices.
Comparative to traditional silicon semiconductors, organic semiconductors have several advantages over their predecessors. They can tolerate higher temperatures while decreasing active cooling requirements and increasing switching frequencies – all features that enable manufacturers to design lighter electric motors with improved efficiency.
Power electronics makers are taking advantage of this technology as they work to meet the ever-increasing demand for electric vehicles. GE, in collaboration with Wolfspeed, developed the SpeedVal Kit which allows users to test performance of SiC devices. Other companies such as McLaren Applied are working towards building inverters which can withstand higher voltage requirements for EVs.
Onsemi has been investing heavily in its state-of-the-art 200 mm wafer facility in Bucheon, South Korea, expanding it towards full production capacity of over one million 200 mm wafers each year.
This marks the first major fab to specialize in silicon carbide production, part of an ongoing trend among semiconductor producers to move away from conventional silicon production due to cost and capacity restrictions.
Silicon carbide’s significantly lower cost has attracted manufacturers of all stripes to it, leading them to take on production. According to Yole Research’s report, 8-inch substrate prices should continue to drop as production ramps up – particularly true for 8-inch substrates where seven manufacturers have reached mass production or will do within one to two years, including two epitaxial plants with combined capacities of 21,000mm2. Yole also notes that demand for silicon carbide power devices will expand over time.
E-Mobility
E-Mobility refers to an umbrella term covering a range of transportation solutions, from cars and buses to trucks and off-road vehicles, along with their supporting infrastructure as well as charging services and solutions.
E-mobility offers multiple environmental and economic benefits. By electrifying transport, global CO2 emissions are decreased and oil use decreased – both steps towards curbing climate change. Furthermore, it promotes economic development as most industries depend on an efficient means of moving goods, customers and employees around.
E-vehicles offer another advantage by helping reduce air pollution. As zero emission vehicles, e-vehicles emit far fewer greenhouse gases and pollutants than traditional combustion engines in urban environments where pollution levels tend to be the highest.
Because of these advantages, demand for e-mobility has skyrocketed, and is only expected to increase further over time. Unfortunately, however, industry representatives face several hurdles that must be overcome to effectively transition towards this form of transport.
One major challenge associated with electric vehicles (EVs) is expanding battery storage capacity. At present, electric car batteries are limited by size of vehicle, amount of power stored and cost. Therefore, innovation must take place to achieve optimum balance among energy density, cost and performance.
At its heart lies a challenge for e-mobility – making sure it is carbon neutral. This requires electricity used to power vehicles from renewable sources rather than coal or fossil fuels; and also being made out of recycled materials so as to truly create green cars.
Manufacturers that wish to succeed will need to employ an integrated and comprehensive strategy when developing products, which addresses these issues simultaneously with product creation. They will need to reimagine their strategies, operating models and supply chains; collaborate among themselves and collaborate on creating new technologies and services that advance e-mobility forward; as well as collaborate between each other in developing such technologies and services that may drive forward e-mobility.
Despite these obstacles, the future of e-mobility remains bright and promising. An increase in electric vehicle use will create a healthier environment, more liveable cities, and a more sustainable economy.