Concept of PVD

PVD = Physical Vapour Deposition

 

• A BRIEF HISTORY :

After many years of research on processes especially in Russia and Germany, surface engineering  has been developed and industrialized  since the 80’s.

PVD is now applied in different industrial branches such as semiconductors, optics, glass, cutting tools and decorative applications. Tribological coatings and solar cells are the most recent developments.

 

   

Chromium target (Cr)                                            Titanium Aluminium target (TiAl)         Aluminium Titanium Silicon target (AlTiSi)

 

 

• BASIC PRINCIPLE:

All processes that allow the transfer from material to an atomic level under vacuum are PVD.

It results a thin film from few nanometers to about 10 microns thick.

 

• The PVD processes :
  • Magnetron sputtering :

1. High vacuum → introduction from a neutral gas (Argon or Nitrogen)
2. Ionized gas (Ar+) → Ions are battering the target which is negative charged
3. Torn atoms → they are coating the substrate

Tungsten Carbide target (WC)                            Silicon Aluminium target (SiAl)                 Aluminium Chromium target (AlCr)

 

• • Evaporation by cathodic arc :

1. High vacuum → introduction from a neutral gas (Argon or Nitrogen)
2. Electrical arc is initiated on the target
3. Electrons flux is battering the cathode
4. Focused heating → evaporation from the material which is coating the substrate

 

Aluminium Titanium target (AlTi)                                           Titanium target (Ti)                                             Chromium target (Cr)

 

• • Joule and electron beam evaporation :

1. Shape of material is granules or wires, loaded in a crucible
2. High vacuum
3. Crucible is heated by a resistance or the material inside is battered with an electron gun
4. Evaporation and next condensation on the substrate

 

Alumina insulator (Al2O3)                                                 Graphite target (C)                                           Ceramic cap