What is the principle working of RF magnetron sputtering process?
As with DC Sputtering, RF Sputtering runs an energetic wave through an inert gas in a vacuum chamber which becomes ionized. The target material or cathode which is to become the thin film coating is bombarded by these high energy ions sputtering off atoms as a fine spray covering the substrate to be coated.
How does magnetron sputter work?
Magnetron sputtering increases the plasma density by introducing a magnetic field on the surface of the target cathode and utilizing the constraints of the magnetic field on the charged particles to increase the sputtering rate.
What is substrate sputtering?
Sputter deposition is a physical vapor deposition (PVD) method of thin film deposition by the phenomenon of sputtering. This involves ejecting material from a “target” that is a source onto a “substrate” such as a silicon wafer.
What is the difference between RF and DC magnetron sputtering?
In RF sputtering, source of power is AC (Alternating Current). Instead of DC voltage to cathode, RF at about 13.5 MHz is being applied….RF sputtering.
| Features | DC Sputtering | RF Sputtering |
|---|---|---|
| Sputtering type | magnetron only | magnetron or diode |
| Target materials | conductive only | All the targets |
How plasma is formed in sputtering?
A plasma is created by ionizing a sputtering gas (generally a chemically inert, heavy gas like Argon). The sputtering gas bombards the target and sputters off the material we’d like to deposit. Ions can be generated by the collision of neutral atoms with high energy electrons.
What is the RF frequency used for sputtering process?
Using power delivered at radio frequencies (RF) – typically at 13.56 MHz – and an automatic impedance matching network, the total impedance of the circuit can be regulated to 50 Ω which is suitable for plasma ignition in typical sputtering environments.
Why do we use RF sputtering instead of DC sputtering?
Typically, RF makes a better thin film than DC, pulsed DC, or AC. The RF-sputtered film will be smoother and have better packing density. RF also deposits the film at about 20% of the DC rate. If you want to sputter using DC, pulsed DC, or AC, you must have a conductive (or semi-conductive) target.