Why isn't my sputtering target working? Why can't I strike a plasma over my sputtering target?
Note: some of the below suggestions appeared in the "Ask Stan" column in the January 2011 Vacuum & Coating Technology magazine:
Charles Albert, PhD
ACI Alloys, Inc.
1. Are you DC-sputtering a target that has high magnetic permeability? If so, you may need to reduce the thickness of the target, or else switch to RF-sputtering.
2. Does your target have low electrical conductivity? If so, you may only be able to do RF sputtering with it.
3. Verify that the ground shield is installed properly, and is not grounding out the target, and that it is creating the necessary "dark space".
4. You may be able to improve the electrical conductivity by applying a conductive paste to the bottom surface of the target, or by bonding the target to a copper backing plate.
5. Be sure you have sufficient water flow cooling the target, and that the exit water is not warm. This may trip an interlock.
6. Check the magnetic field: for a 2" magnetron gun, it should be several hundred gauss at 1cm from the target.
7. Make sure the system pressure is not too high. Look for signs of internal discharge besides on the substrate.
8. Has the target been properly degreased, and handled only with clean, lint-free gloves?