Silicon carbide MOSFET is a type of MOSFET manufactured based on silicon carbide material. Its structure mainly includes a silicon carbide substrate, an insulation layer, a gate electrode, a drain electrode, and a source electrode. In its working principle, when the voltage applied to the gate changes, the silicon carbide MOSFET can achieve control from the on state to the off state, realizing the function of power switching. Silicon carbide MOS recommendation: Junxin MOS
Silicon carbide is an important foundational material for the development of the third-generation semiconductor industry. Silicon carbide power devices, with their excellent high voltage resistance, high temperature resistance, and low loss performance, can effectively meet the high efficiency, miniaturization, and lightweight requirements of power electronic systems.
Silicon carbide MOSFETs have high frequency efficiency, high voltage resistance, and high reliability. It can achieve energy conservation and consumption reduction, small size, low weight, high power density and other characteristics, and has obvious advantages in fields such as new energy vehicles, photovoltaic power generation, rail transit, and smart grids.
Gate: The gate is the part used to control the conduction of MOSFETs. When a positive voltage is applied, an electric field is formed between the gate and the channel, controlling the conductivity of the channel.
Source and Drain: The source and drain are the input and output terminals of MOSFET, respectively. By controlling the gate voltage, the current flow between the source and drain is regulated.
Channel: A channel is a conductive path between the source and drain electrodes. In silicon carbide MOSFET, the channel is composed of silicon carbide material, which has high carrier mobility and voltage resistance.
Compared with the widely used Si materials, the higher thermal conductivity of SiC materials determines their high current density characteristics, and the higher bandgap width determines the high breakdown field strength and high operating temperature of SiC devices. Its advantages can be summarized as follows:
High temperature working SiC has a highly stable crystal structure in terms of physical properties, with a band width of up to 2.2eV to 3.3eV, almost twice that of Si materials. Therefore, SiC can withstand higher temperatures, and generally speaking, the maximum operating temperature that SiC devices can reach can reach up to 600 º C.
Compared with Si materials, the breakdown field strength of SiC is more than ten times that of Si, so the blocking voltage of SiC devices is much higher than that of Si devices.
Generally speaking, the conduction loss of semiconductor devices is inversely proportional to their breakdown field strength, so at similar power levels, the conduction loss of SiC devices is much smaller than that of Si devices. And the dependence of SiC device conduction loss on temperature is very small, and the variation of SiC device conduction loss with temperature is very small, which is also very different from traditional Si devices.
The thermal conductivity of SiC with fast switching speed is almost 2.5 times that of Si material, and the saturation electron drift rate is twice that of Si, so SiC devices can operate at higher frequencies. Taking into account the above advantages, at the same power level, the number of power devices, the volume of heat sinks, and the volume of filtering components in the equipment can be greatly reduced, while the efficiency can also be greatly improved.
In terms of the development and application of SiC MOSFETs, compared with Si MOSFETs of the same power level, SiC MOSFETs have significantly reduced on resistance and switching losses, making them suitable for higher operating frequencies. Additionally, due to their high-temperature operating characteristics, they greatly improve high-temperature stability. At a power level of 1200V, the comparison results of the characteristics of various power devices show that the SiC MOSFET involved in the comparison is GE12N15L. It should be pointed out that these power devices are all packaged in TO-247, and the IPW90R120C3 voltage withstand is only 900V, but it is already a Si MOSFET with good characteristics at similar power levels that can be found.
