Sputter cleaning
Encyclopedia
Sputter cleaning is the cleaning of a solid surface in a vacuum
by using physical sputtering
of the surface. Sputter cleaning is often used in vacuum deposition
and ion plating
. In 1955 Farnsworth, Schlier, George, and Burger reported using sputter cleaning in an ultra-high-vacuum system to prepare ultra-clean surfaces for low-energy electron-diffraction (LEED) studies. Sputter cleaning became an integral part of the ion plating
process. Sputter cleaning has some potential problems such as overheating, gas incorporation in the surface region, bombardment (radiation) damage in the surface region, and the roughening of the surface, particularly if over done. It is important to have a clean plasma
in order to not continually recontaminate the surface during sputter cleaning. Redeposition of sputtered material on the substrate can also give problems, especially at high sputtering pressures.
Sputtering of the surface of a compound or alloy material can result in the surface composition being changed. Often the species with the least mass or the highest vapor pressure
is the one preferentially sputtered from the surface.
Vacuum
In everyday usage, vacuum is a volume of space that is essentially empty of matter, such that its gaseous pressure is much less than atmospheric pressure. The word comes from the Latin term for "empty". A perfect vacuum would be one with no particles in it at all, which is impossible to achieve in...
by using physical sputtering
Sputtering
Sputtering is a process whereby atoms are ejected from a solid target material due to bombardment of the target by energetic particles. It is commonly used for thin-film deposition, etching and analytical techniques .-Physics of sputtering:...
of the surface. Sputter cleaning is often used in vacuum deposition
Vacuum deposition
Vacuum deposition is a family of processes used to deposit layers atom-by-atom or molecule-by-molecule at sub-atmospheric pressure on a solid surface. The layers may be as thin as one atom to millimeters thick . There may be multiple layers of different materials...
and ion plating
Ion plating
Ion plating is a physical vapor deposition process that is sometimes called ion assisted deposition or ion vapor deposition and is a version of vacuum deposition. Ion plating utilizes concurrent or periodic bombardment of the substrate and depositing film by atomic-sized energetic particles...
. In 1955 Farnsworth, Schlier, George, and Burger reported using sputter cleaning in an ultra-high-vacuum system to prepare ultra-clean surfaces for low-energy electron-diffraction (LEED) studies. Sputter cleaning became an integral part of the ion plating
Ion plating
Ion plating is a physical vapor deposition process that is sometimes called ion assisted deposition or ion vapor deposition and is a version of vacuum deposition. Ion plating utilizes concurrent or periodic bombardment of the substrate and depositing film by atomic-sized energetic particles...
process. Sputter cleaning has some potential problems such as overheating, gas incorporation in the surface region, bombardment (radiation) damage in the surface region, and the roughening of the surface, particularly if over done. It is important to have a clean plasma
Plasma (physics)
In physics and chemistry, plasma is a state of matter similar to gas in which a certain portion of the particles are ionized. Heating a gas may ionize its molecules or atoms , thus turning it into a plasma, which contains charged particles: positive ions and negative electrons or ions...
in order to not continually recontaminate the surface during sputter cleaning. Redeposition of sputtered material on the substrate can also give problems, especially at high sputtering pressures.
Sputtering of the surface of a compound or alloy material can result in the surface composition being changed. Often the species with the least mass or the highest vapor pressure
Vapor pressure
Vapor pressure or equilibrium vapor pressure is the pressure of a vapor in thermodynamic equilibrium with its condensed phases in a closed system. All liquids have a tendency to evaporate, and some solids can sublimate into a gaseous form...
is the one preferentially sputtered from the surface.