The fundamental difference between structure and working principle:

1.MOSFET：
Pure field-effect devices belong to unipolar devices.
The conductivity depends only on the majority of charge carriers (N channel is electrons, P channel is holes).
When conducting, a conductive channel is formed under the action of gate voltage, and current flows from the drain to the source.
IGBT：
Composite equipment. It can be seen as a MOSFET that drives bipolar transistors.
Combine the gate voltage control of MOSFET with the low conduction voltage drop characteristics of bipolar transistor.
The conductive mechanism involves both majority carriers and minority carriers.
When conducting, the MOSFET part forms a channel, which serves as the base current of the bipolar transistor, causing the bipolar transistor to conduct and generate a strong conduction modulation effect, allowing large currents to pass through.
The IGBT module contains multiple IGBT chips (connected in parallel to improve current capability) and necessary anti parallel fast recovery diode chips.

Key performance differences:
2. Voltage and current capability:
MOSFET: Excellent performance at low voltage. However, the on resistance of high-voltage MOSFETs increases sharply with the increase of withstand voltage level, resulting in excessive conduction loss and low efficiency. Usually suitable for<250V (preferably<100V), low or medium current applications. High voltage MOSFETs (such as 900V) have high costs and low efficiency.
IGBT module: designed specifically for medium to high voltage and high current. At high voltage (>600V) and/or high current, its conduction voltage drop is much lower than that of high voltage MOSFETs, and its conduction loss advantage is obvious. The voltage range is usually 600V to 6500V or even higher, and the current can reach hundreds or even thousands of amperes.

Conduction loss:
3. MOSFET: It has extremely low conduction loss at low voltage and low current. But under high voltage or high current, due to the large on resistance, the loss increases sharply.
IGBT module: The conduction loss at high voltage and high current is significantly lower than that of MOSFETs at the same voltage and current levels. This is the main reason why IGBT replaces MOSFET in high-voltage and high-power fields. The conduction pressure drop is relatively fixed.

Switch loss and speed:
4. MOSFET: It has extremely fast switching speed (especially turn off speed) and very low switching loss. Very suitable for high-frequency switch applications (tens of kHz to MHz).
IGBT module: The switching speed is slower than MOSFET (especially the tail current when turned off), resulting in higher switching losses than MOSFET. The operating frequency is usually limited to a few tens of kHz (20kHz-50kHz is common, and new models can reach 100kHz+). The encapsulation structure of modules can also introduce certain parasitic parameters that affect speed.

Input characteristics and driving factors:
5. Both are voltage controlled devices (gate driven) with relatively simple driving circuits and lower driving power (compared to current driven devices such as thyristors and BJTs). This is their common huge advantage.
Temperature characteristics:
MOSFET: The on resistance has a positive temperature coefficient (Rds (on) increases with temperature). This is beneficial for automatic current sharing of parallel devices.
IGBT module: The conduction voltage drop has a slight negative temperature coefficient (Vce (sat) decreases slightly with increasing temperature). When used in parallel, more refined design (such as matching, driving, layout) is required to ensure current sharing.
Anti short circuit capability:
IGBT typically has stronger short-circuit withstand capability (over a period of time) than MOSFET, which is important in certain industrial drive applications