1. PHYSICAL VAPOR DEPOSITION ( PVD)
By: Ellen kay R. Cacatian
2. Physical Vapor deposition
is a variety of vacuum deposition & is a general term used to
describe any of a variety of methods to deposit thin films.
condensation of a vaporized form of the material onto various
surfaces (semiconductorwafers).
Films depositedcommonly directional rather than conformal.
The coating method involves purely physical processes such as high
temperature vacuum evaporation or plasma sputter bombardment rather
than involving a chemical reaction.
3. Physical Vapor Deposition
coating technique, involving transfer of material on an atomic
level.
It is an alternative process to electroplating.
Thin film processes
nanometersto thousands of nanometers, used to form multilayer
coatings, graded composition deposits.
4. Physical Vapor Deposition
The process is similar to (CVD)
Except that the raw materials/precursors of the material that is
going to be deposited starts out in solid form.
5. Types of Deposition:
Cathodic Arc Deposition:
In which a high power arc discharged at the target material blasts
away some into highly ionized vapor.
Electron beam deposition:
In which the material to be deposited is heated to a high vapor
pressure by electron bombardment in "high" vacuum.
6. Types of Deposition:
Evaporative deposition:
In which the material to be deposited is heated to a high vapor
pressure by electrically resistive heating in "low" vacuum.
7. Types of Deposition
Pulsed laser deposition:
In which a high power laser ablates material from the target into a
vapor
8. Types of Deposition:
Sputter deposition:
In which a glow plasma discharge (usually localized around the
"target" by a magnet) bombards the material sputtering some away as
a vapor. Here is an animation of a generic PVD sputter tool.
Ion beam and reactive
9. How Does Physical Vapor Deposition Work?
Evaporation
Transportation
Reaction
Deposition
10. Evaporation
During this stage, a target consisting of the material to be
deposited is bombarded by a high energy source such as a beam of
electrons or ions. vaporizing them.
Evaporation involves two basic processes:
evaporates ( Evaporation)
Condenses(Condensation)
11. Evaporation Deposition Steps:
Load the source material-to-be-deposited (evaporant) into the
container (crucible)
Heat the source to high temperature
Source material evaporates
Evaporantvapor transports to and Impinges on the surface of the
substrate
12. Evaporation:
Evaporant condenses on and is adsorbed by the surface
Any evaporation system includes a vacuum pump. It also includes an
energy source that evaporates the material to be deposited
13. Transport
This process simply consists of the movement of vaporized atoms
from the target to the substrate to be coated and will generally be
a straight line affair
14. Reaction
In some cases coatings will consist of metal oxides, nitrides,
carbides and other such materials. In these cases, the target will
consist of the metal.
The atoms of metal will then react with the appropriate gas during
the transport stage. the reactive gasesare:
oxygen, nitrogen and methane.
In instances where the coating consists of the target material
alone, this step would not be part of the process.
15. Deposition
This is the process of coating build up on the substrate
surface.
Depending on the actual process, some reactions between target
materials and the reactive gases may also take place at the
substrate surface simultaneously with the deposition process.
16. What is PVD Coatings Used For?
