MOSFETs

MOSFETs (Metal Oxide Semiconductor Field-Effect Transistors) are voltage controlled devices which control the flow of current with an applied voltage. They are a special type of field-effect transistor that works by electronically varying the width of a channel along which charge carriers (electrons or holes) flow. The wider the channel, the better the device conducts. The charge carriers enter the channel at the source and exit via the drain. The width of the channel is controlled by the voltage on an electrode, called the gate, which is located physically between the source and the drain. It is insulated from the channel by an extremely thin layer of metal oxide.