Ta PVD Target Racetrack Erosion Reduces Target Utilization - Functional Modeling
Temperature compensation is an interesting idea, but not the most practical solution for improving Ta target utilization.
Move or scan the magnetron field
If the racetrack is caused by magnetic field localization, then move the magnetic field during the target lifetime. The erosion zone will move, and Ta will be consumed more uniformly.
Change magnet configuration
Design the magnetron so that the plasma density is distributed over a wider area, not concentrated in one narrow ring.
Use a variable magnetic-field profile during target life
At the beginning, use one racetrack position; later, shift it slightly inward or outward. This can spread erosion over more target area.
Pre-shape the Ta target
This is closer to your compensation idea. Instead of heating, make the target initially thicker where erosion will be strongest. Then the target profile becomes more uniform during usage.
Use multi-zone magnetron control
If possible, control several magnetic zones to redistribute plasma density and ion bombardment.
Improve redeposition management
Since Ta atoms are sputtered in many directions, shields and chamber walls receive Ta redeposition. Their shape and replacement schedule should be part of the same model.
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