MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistors) are the mainstream voltage-driven power semiconductor devices. Their core principle is to control the on/off of the conductive channel and the current magnitude between the drain and source through the gate voltage, featuring extremely high input impedance, minimal driving power, fast switching speed, low power consumption and easy integration. They are classified by conductive channel into N-channel (market mainstream) and P-channel, by structure into planar and trench types, and by power into small-signal MOSFETs and power MOSFETs. They are widely used in consumer electronics power supplies, new energy vehicle electronic controls, photovoltaic inverters, industrial frequency converters, communication base station power supplies and various switching power supply circuits, serving as the core devices for medium and low-voltage high-power power conversion and electronic switch control.