Sputtering is a physical vapour deposition (PVD) technique used to create thin film coatings by ejecting atoms from a solid target material and depositing them onto a substrate, which in our case are Reed Blades. This process occurs inside a vacuum chamber, where inert gas ions, typically Argon, are accelerated towards the target material (cathode). The impact dislodges atoms from the target, which then travel through the chamber and adhere to the surface of the substrate, forming a thin, uniform layer.
Preparation
Special magnetic alloy parts are placed in high-grade Aluminium fixtures.
These fixtures are then loaded into the vacuum chamber which has a Magnetron, additional vacuum technology and a Ruthenium target.
Vacuum Setup
The chamber is evacuated to 5E-5 torr using a cryogenic-pump, which evacuates the air and impurities in the chamber into a frozen ball at -270°C.
Inert Gas Injection
Argon gas is introduced into the chamber as they are large molecules.
Sputtering Process
The magnetron is turned on and the Argon atoms are bombarded. The potential difference of -600V is set between the Ruthenium target and the sensor parts. Plasma forms around the Ruthenium target, causing Ruthenium atoms to be ejected and deposited on the parts.
Coating
The coating process or sputtering takes a few minutes to achieve a thickness of 0.4 microns.
Venting
The chamber vented and brought back to atmospheric pressure.
Coated parts are unloaded for the next step: glass-to-metal sealing in a Clean Room.
