Sputtering technology

Steps involved in the sputtering process:

1. Evacuate the chamber: First, the sputtering chamber is evacuated to remove foreign molecules.

2. Introduction of the sputtering gas: An inert gas – typically argon – is introduced into the chamber.

3. Generation of a plasma: By applying an electrical voltage, the gas is ionized, and a plasma is created.

4. Firing at the target: The ionized gas particles are accelerated by the electric field and hit the target.

5. Deposition on the substrate: The atoms or molecules detached from the target move through the chamber and are deposited as a thin film on the substrate.
 

Variants of sputtering:

• Co-sputtering: Co-sputtering involves the simultaneous coating with several sputter sources.
• Confocal sputtering: Coating with inclined sputter sources during rotation, which enables coating with smaller sources.
• Magnetron sputtering: A magnetic field is used to concentrate the plasma closer to the target, which increases the sputtering rate and renders the process more efficient.
   

Advantages of sputtering:

• Uniform coating thicknesses: Sputtering enables the deposition of very uniform and reproducible coatings.
• Flexibility: Various materials can be used as targets – including metals, alloys, and oxides.
• High degree of purity: As the process takes place in a vacuum chamber, very pure coatings can be produced.