VMOS is an acronym for Vertical Metal Oxide Semiconductor (Transistor). Vmos is also used to describe the V-groove shape vertically cut into the substrate material metal oxide semiconductor transistor

MOSFET

The metal–oxide–semiconductor field-effect transistor is a transistor used for amplifying or switching electronic signals. The basic principle of this kind of transistor was first patented by Julius Edgar Lilienfeld in 1925...

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The "V" shape of the MOSFET

MOSFET

The metal–oxide–semiconductor field-effect transistor is a transistor used for amplifying or switching electronic signals. The basic principle of this kind of transistor was first patented by Julius Edgar Lilienfeld in 1925...

's gate

Gate oxide

The gate oxide is the dielectric layer that separates the gate terminal of a MOSFET from the underlying source and drain terminals as well as the conductive channel that connects source and drain when the transistor is turned on. Gate oxide is formed by oxidizing the silicon of the channel to form...

 allows the device to deliver a higher amount of current

Electric current

Electric current is a flow of electric charge through a medium.This charge is typically carried by moving electrons in a conductor such as wire...

 from the source  to the drain  of the device. The shape of the depletion region

Depletion region

In semiconductor physics, the depletion region, also called depletion layer, depletion zone, junction region or the space charge region, is an insulating region within a conductive, doped semiconductor material where the mobile charge carriers have diffused away, or have been forced away by an...

 creates a wider channel, allowing more current to flow through it.

This structure has a V-groove at the gate region and was used for the first commercial devices.

The device was used as a power device until more suitable geometries, like the UMOS (or Trench-Gate MOS) were introduced in order to lower tmaximum electric field

Electric field

In physics, an electric field surrounds electrically charged particles and time-varying magnetic fields. The electric field depicts the force exerted on other electrically charged objects by the electrically charged particle the field is surrounding...

 at the top of the V shape and thus leading to higher maximum voltages than in case of the VMOS.

VMOS was invented by T. J. Rodgers

T. J. Rodgers

Thurman John Rodgers, better known as T.J. Rodgers, is the founder and chief executive officer of Cypress Semiconductor. He is known for his public relations acumen, brash personality, and strong advocacy of laissez-faire capitalism.-Early life:...

 while he was a student at Stanford University

Stanford University

The Leland Stanford Junior University, commonly referred to as Stanford University or Stanford, is a private research university on an campus located near Palo Alto, California. It is situated in the northwestern Santa Clara Valley on the San Francisco Peninsula, approximately northwest of San...

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