Sputtering is the
preferred vacuum deposition technique used by manufacturers
of semiconductors, CDs, disk drives, and optical devices.
Sputtered films exhibit excellent uniformity, density, purity
and adhesion. It is possible to produce alloys of precise
composition with conventional sputtering, or oxides, nitrites
and other compounds by reactive sputtering.
Substrates are placed into the
vacuum chamber, and are pumped down to their process pressure.
Sputtering starts when a negative charge is
applied to the target material (material to be deposited),
causing a plasma or glow discharge.
Positive charged gas ions generated in the plasma region are
attracted to the negative biased target plate at a very high
speed. This collision creates a momentum transfer and ejects
atomic size particles from the target. These particles traverse
the chamber and are deposited as a thin film onto the surface
of the substrates.
|