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The sputtering is a physical manufacturing process that involves coating
a substratum with metal particles. The manufacturing process takes place
in a high vacuum chamber and the coating process involves three stages,
stabilizing layer coating, semi-conductor layer coating (radiation
absorbent layer) and anti-refection layer coating, as shown in the
following diagram.
In the vacuum chamber three target plates are installed above the
copper fin. By creating a high-tension field between the targets and the
copper fin and a magnetic field parallel to the target plates, positive
helium ion release titanium atoms from the target plate. The atoms
strike the copper fin and because of First, a stabilizing layer of pure titanium is laid on the copper fin. This layer gives the surface of the copper fin long-term stability. Secondly, the titanium atoms react with oxygen to form an absorbent layer of titanium oxide (TINOx) on the first layer. In this semi-conductor layer titanium atoms are orientated in such a way that 98% of incoming solar radiation can be absorbed. Finally, an anti-reflection layer is added on the absorbent layer. The anti-reflection layer has a very low reflection index and can let 98 to 99 % of incident solar radiation pass through the layer to be absorbed by the semi-conductor layer. |
high kinetic energy of the atoms
they attach themselves to the top of the copper fin. During the process
this copper fin passes three targets plates.