Power Electronics 4 - The MOSFET

摘要

In his last article Rob Easthope considered the Junction Gate Field Effect Transistor or JFET. In this, his latest article, he examines the power version of the FET, the Metal Oxide Semiconductor Field-Effect Transistor or MOSFET. Like the JFET the MOSFET also has a gate, a drain and a source, but unlike the JFET the gate is insulated. A very simplified diagram of the MOSFET construction is shown in Figure 1. The gate insulator is typically made from an oxide (such as silicon dioxide) overlaid with a layer of silicon nitride. This is an Insulated Gate Field-Effect Transistor or IGFET.