The functions of a backing plate are:
- supporting the target esp. the weak target materials during sputtering such as ceramic and soft metallic materials
- provide heat extraction(cooling) from Sputtering process
Sealing from magnetron cooling system and vacuum chamber
Selection of Backing Plate materials where the following factors must be considered:
- Thermal Expansion of the Backing plate materials and Sputtering target.
- Electrical Conductivity
- Mechanical Properties to withstand the cooling water pressure and thermal cycling effect.
Backing plate materials available in our plant are:
Oxygen Free Copper (Cu backing plate)
The most commonly backing materials is is Oxygen Free Copper (OFHC) .This is readily available metal has good thermal conductivity and electrical conductivity, while also being easy to machine. Copper backing plates can be re-used, with care, twenty times or more.
Molybdenum Backing Plate (Mo backing plate)
Molybdenum Backing Plate is suitable for high temperature bond , while copper may also oxidize badly or warp, and also matching with target materials where copper coefficient of expansion is mismatched, such as ceramics.
Aluminium Backing plate (Al backing plate)
Similarly for high thermal conductivity and matching to the target materials coefficient of expansion as well as suitable for diffusion bonding.
Commonly used for Rotatable sputtering target where it provide a low cost recyclable backing tube.
Moreover, copper zinc (CuZn) alloy and copper chromium (CuCr) alloy backing plate are also available in our plant, if you are interested, please contact our sales engineeers for more information.