Structure and Composition
Operation
Advantages
Applications
Unique Gate Structure
What makes the IGBT different from other transistors is the addition of a gate structure, like in a MOSFET, on top of the drift region. This gate is separated from the drift region by a thin insulating layer, usually silicon dioxide (SiO2), allowing precise control over the device. The gate structure has a metal electrode separated from the drift region by the insulating layer.
Entering the On State
When the gate voltage reaches a certain level, called the threshold, the IGBT turns on. In this “on-state”, current can flow easily from the collector to the emitter. The voltage applied to the gate controls how well the channel conducts electricity, allowing precise control over the current flow.
