Electron Beam Evaporator

The E-beam evaporator is located in room 20b of the ASTeCC building. It is useful for metals, oxides, and refractory materials. It has a rotary table capable of holding 4 deposition sources and can be utilized for several layers of deposition without breaking the chamber vacuum. Recommended maximum deposition thickness is 300 nm (3,000 A).

The Center does not provide crucible liners or evaporation materials. Crucibles are available from various sources; part number EVCEB-4 from www.lesker.com is the proper size for the evaporator.

• Commonly used in GaAs technologies.
• Can easily deposit a wide range of materials.
• Multiple layers can easily be formed without releasing the vacuum.
• The film can be made very thick or thin, and thickness is easily controlled.

Electron Beam Physical Vapor Deposition or EBPVD is a form of physical vapor deposition in which a target anode is bombarded with an electron beam given off by a charged tungsten filament under high vacuum. The electron beam causes atoms from the target to transform into the gaseous phase. These atoms then precipitate into solid form, coating everything in the vacuum chamber with a thin layer of the anode material.

Alternatives to evaporation, such as sputtering and chemical vapor deposition, have better step coverage. This may be an advantage or disadvantage, depending on the desired result.Sputtering tends to deposit material more slowly than evaporation.Sputtering uses a plasma, which produces many high-speed atoms that bombard the substrate and may damage it. Evaporated atoms have a Maxwellian energy distribution, determined by the temperature of the source, which reduces the number of high-speed atoms. However, electron beams tend to produce X-rays (Bremsstrahlung) and stray electrons, each of which can also damage the substrate.

"Electron beam physical vapor deposition." Wikipedia, The Free Encyclopedia. 3 Aug 2007, 11:33 UTC. Wikimedia Foundation, Inc. 24 Jan 2008 <http://en.wikipedia.org/w/index.php?title=Electron_beam_physical_vapor_deposition&oldid=148911781>.