The Fowler-Nordheim Equation describes the quantum mechanical tunneling of electrons through a potential barrier, a phenomenon critical for understanding field emission in vacuum microelectronics. It relates the current density of emitted electrons to the electric field and work function of the emitting material, providing a framework for analyzing electron emission in devices like field emission displays and electron microscopes.

Fowler-Nordheim Equation

Quantum mechanical tunneling

A potential barrier is a region in a field where the potential energy of a particle is higher than its surrounding areas, often preventing the particle from passing through unless it possesses sufficient energy. It is a fundamental concept in quantum mechanics, where particles exhibit wave-like behavior, allowing them to tunnel through barriers even when they seemingly lack the energy to overcome them classically.

Potential Barrier

Field emission is the process where electrons are emitted from a material surface due to the presence of a strong electric field, overcoming the work function barrier without the need for thermal energy. This quantum mechanical phenomenon is crucial in technologies like electron microscopes and vacuum electronic devices, where precise control of electron flow is required.

Field Emission

Vacuum Microelectronics

Current density of emitted electrons

An electric field is a vector field around a charged particle that represents the force exerted on other charges placed within the field. The strength and direction of the electric field are determined by the magnitude and sign of the charge, as well as the distance from the charge.

Electric Field

The work function is the minimum energy needed to remove an electron from the surface of a material, typically a metal, and is a critical parameter in determining the electronic and optical properties of materials. It plays a vital role in technologies like photovoltaics, electron emission devices, and semiconductor physics, influencing the efficiency and behavior of these systems.

Work Function

Emitting material

Electron emission is the process by which electrons are ejected from a material, typically a metal, due to external stimuli such as heat, light, or electric fields. This phenomenon is crucial in various applications, including cathode ray tubes, electron microscopes, and vacuum tubes, where controlling electron flow is essential.

Concepts

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