Ion beam

Beam of charged atoms (ions) A small ion beam rocket being tested by NASA. An ion beam is a beam of ions, a type of charged particle beam. Ion beams have many uses in electronics manufacturing (principally ion implantation) and other industries. There are many ion beam sources, some derived from the mercury vapor thrusters developed by NASA in the 1960s. The most widely used ion beams are of singly-charged ions. Units Ion current density is typically measured in mA/cm2, and ion energy in electronvolts (eV). The use of eV is convenient for converting between voltage and energy, especially when dealing with singly charged ion beams. Broad-beam ion sources Most commercial applications use two popular types of ion source, gridded and gridless, which differ in current and power characteristics and the ability to control ion trajectories. In both cases electrons are needed to generate an ion beam. The most common types of electron emitter are hot filament and hollow cathode. Gridded ion source In a gridded ion source, DC or RF discharge are used to generate ions, which are then accelerated and decimated using grids and apertures. Here, the DC discharge current or the RF discharge power a