Silicon Carbide (SiC) MOSFETs have become an attractive alternative to silicon IGBT devices in components rated for 1 kV or above, offering high performance switching advantages in a small package. Wolfspeed’s 3rd Generation SiC MOSFET, C3M0075120D provides this high performance switch in an increasingly common solution.
Silicon devices offer many advantages over their metal-oxide counterparts, including lower on state resistance and increased blocking voltage. As a result, these devices make ideal choice for motor drives, uninterruptible power supplies (UPS), and photovoltaic inverters.
Power density
As the demand for power continues to increase, so has the demand for smaller components and higher efficiency. Silicon Carbide (SiC) power devices offer potential solutions to these challenges by offering higher switching frequencies, lower resistance conduction and wider temperature ranges resulting in increased power density as well as operating at higher temperatures while decreasing heat generation by circuits.
SiC MOSFETs can be utilized in numerous applications, including AC/DC converters, DC/DC converters and uninterruptible power supplies. Their lower conduction resistance, faster switching speed and larger temperature range give designers greater design freedom over traditional silicon devices; furthermore they are able to withstand higher junction temperatures which helps lower overall system costs and enhance reliability.
SiC-based MOSFETs boast one major advantage over their silicon counterparts in that they support larger output capacitance, which allows manufacturers to utilize smaller external gate resistors while still reaching the same output voltage – something especially helpful in complex circuit topologies like LLC resonant power converters.
Though SiC-based power devices may boast many advantages, many experts still maintain that silicon MOSFETs remain relevant due to their boost functionality which requires a body diode with higher threshold voltage than silicon MOSFETs, thus decreasing efficiency gains. Therefore it is critical that dead time of SiC MOSFETs be optimized by SCALE gate drivers in order to ensure maximum efficiency gains.
High efficiency
Over many years, researchers have conducted extensive work to develop better silicon power-switching devices. Unfortunately, their efforts had reached their limit and new technologies were necessary. SiC MOSFETs offered the solution – increasing switching frequencies without increasing power losses or heat generation was key in reaching new levels of performance.
SiC MOSFETs boast higher critical breakdown electric fields (VDS) than their silicon counterparts, allowing them to operate at higher voltage ratings and faster switching speeds for greater power density. Furthermore, SiC MOSFETs boast lower gate leakage currents and decreased Miller turn-on loss which help increase efficiency.
SiC MOSFETs boast excellent temperature resistance. In contrast with silicon super junction transistors (SJT) and integrated gate bipolar transistors (IGBT), siC MOSFETs are designed to withstand higher temperatures without their properties deteriorating, making them suitable for use in applications like EV chargers, UPS units and solar string inverters.
To maximize efficiency, many manufacturers of SiC MOSFETs employ separate Schottky barrier diodes on both drain and source sides to lower body-drain voltage and decrease switching losses, as well as increase slew rates for fast switching rates. Furthermore, several companies provide SCALE gate drivers specifically designed to drive SiC MOSFETs; such drivers are an essential element of any high-efficiency power switching design.
Wide bandgap
Wide bandgap semiconductors have revolutionized electronics. Capable of operating at higher temperatures and switching voltages/frequencies than their silicon-based predecessors, wide bandgap semiconductors offer many additional benefits while being much more energy-efficient than their silicon equivalents.
Wide bandgap power semiconductors’ biggest advantage lies in their larger energy gap, enabling them to switch at higher frequencies and voltages with no loss in efficiency, while experiencing lower switching losses than conventional silicon devices.
Wide bandgap semiconductors also boast high electron mobility, which allows for easier current transmission between source and drain terminals and lower on-resistance and lower ohmic losses, increasing efficiency.
SiC devices benefit from having higher electron mobility than conventional silicon devices, enabling higher switching frequencies due to its wider bandgap which allows for a thinner depletion region which reduces on-resistance and on-resistance.
SiC MOSFETs have proven themselves ideal for applications such as traction inverters, motor drives and DC-DC converters due to their advantages in reliability and damage prevention. weEn Semiconductors’ SCALE gate drivers provide a suitable gate drive circuit that controls positive and negative drive voltages of SiC MOSFETs using resonant LLC topologies, thus enabling reliable operation at higher switching frequencies without incurring ZVS (zero voltage standing) crosstalk issues.
Lower on-resistance
Silicon Carbide (SiC) power MOSFETs feature lower on-resistance, making them suitable for use in power electronics circuits without excessive losses. Furthermore, SiC devices boast lower switching loss than conventional Si devices thereby further lowering overall system losses. Unfortunately, lowering specific on-resistance requires improving gate oxide reliability; an extremely challenging task which has yet to be fully optimized in commercial SiC power MOSFETs.
Resistance of a MOSFET depends on various factors, including its drift region and free electron counts in its inversion channel. Temperature plays a key role here and resistance will differ over the operating range of each MOSFET device.
SiC MOSFETs offer excellent ON resistance performance at increasing voltage levels, making them ideal for use in high-voltage applications such as traction inverters and motor drives.
ROHM offers an expansive selection of SiC power MOSFETs with low ON resistance. These devices come in compact packages to meet various applications; typically the larger the chip surface area is, the lower its ON resistance is. In addition, ROHM’s SiC MOSFETs include some resistance from their package due to inactive areas used for termination and scribe lanes that do not carry current.
English 
Swedish