This picture (shared by Angstrom Sciences) shows a planar target plate that has developed an advanced case of nodule formation. Nodules occur when material is re-deposited back onto the sputtering target. This is normal for most sputtering targets – although nodules increase the occurrence of arcing by building up charge on the target surface.
Equipment suppliers can suppress nodule formation (and arcing) by offering:
- high yield magnetrons
- full-face erosion magnetrons
- rotary magnetrons
The transfer efficiency of planar targets is based on magnetron design. High yield and full-face erosion magnetrons sweep the sputtering tool’s magnets over more of the sputtering target's surface – so the racetrack is more uniform. The next step is to move to rotary magnetrons for a decrease in arcing and huge increase in target utilization!
Feel free to contact me to discuss this in detail.