Electron beam (e-beam) evaporation is a time-tested deposition technology for producing dense, high purity coatings. During an e-beam evaporation process, current is first passed through a tungsten filament, leading to joule heating and electron emission. - High voltage is applied between the filament and the hearth to accelerate these liberated electrons toward the crucible containing the material to be deposited. - A strong magnetic field focuses the electrons into a unified beam; upon arrival, the energy of this beam of electrons is transferred to the deposition material, causing it to evaporate (or sublimate) and deposit onto the substrate. - Adding a partial pressure of reactive gas, such as oxygen or nitrogen, to the chamber during evaporation can be used to reactively deposit non-metallic films. High Temperatures: The e-beam source is capable of heating materials to much higher temperatures than is possible using a resistive boat or crucible heater. This allows for very high deposition rates and evaporation of high-temperature
