Note that the threshold voltage for this device lies around 0. It has an insulated gate, whose voltage determines the conductivity of the device. A metal-insulator-semiconductor field-effect transistor or MISFET is a term almost synonymous with MOSFET. Another synonym is IGFET for field effect transistor audio amplifier pdf-gate field-effect transistor.
The main advantage of a MOSFET is that it requires almost no input current to control the load current, when compared with bipolar transistors. MOSFET, voltage applied to the gate terminal increases the conductivity of the device. Similarly, “oxide” in the name can also be a misnomer, as different dielectric materials are used with the aim of obtaining strong channels with smaller applied voltages. Twenty five years later, when Bell Telephone attempted to patent the junction transistor, they found Lilienfeld already holding a patent, worded in a way that would include all types of transistors. MOSFET was made by putting an insulating layer on the surface of the semiconductor and then placing a metallic gate electrode on that. The silicon MOSFET did not generate localized electron traps at the interface between the silicon and its native oxide layer, and thus was inherently free from the trapping and scattering of carriers that had impeded the performance of earlier field-effect transistors. Photomicrograph of two metal-gate MOSFETs in a test pattern.