IGBT device

An insulated gate bipolar transistor (IGBT) device, comprising:

• an n-type collector region, a p-type collector region, an n-type drift region located above the n-type collector region and the p-type collector region, and an metal-oxide-semiconductor field effect transistor (MOSFET) cell array composed of a plurality of MOSFET cells;
• wherein each of the plurality of MOSFET cells comprises:
• a p-type body region located at a top of the n-type drift region, an n-type emitter region located in the p-type body region, and a gate structure located above the p-type body region, wherein the gate structure comprises a gate dielectric layer, a gate electrode and an n-type floating gate, the gate electrode and the n-type floating gate are located above the gate dielectric layer, the gate electrode is located on a side close to the n-type emitter region, the n-type floating gate is located on a side close to the n-type drift region, and the gate electrode acts on the n-type floating gate through capacitive coupling;
• and
• wherein in the MOSFET cell array, the n-type floating gate of at least one of the plurality of MOSFET cells is isolated from the p-type body region through the gate dielectric layer, and the n-type floating gate of at least one of the plurality of MOSFET cells contacts the p-type body region through an opening to form a p-n junction diode, wherein the opening is located in the gate dielectric layer below the n-type floating gate.