Ta PVD Target Racetrack Erosion Reduces Target Utilization - Functional Modeling
Current situation
In Ta PVD, the Ta/TaN sputtering target experiences non-uniform erosion, leading to the formation of a deep racetrack groove that necessitates premature replacement despite significant remaining material. This localized erosion, driven by the magnetron's magnetic-field configuration, concentrates plasma and sputtering efficiency in a narrow area, ultimately reducing target life and increasing consumable costs. Attempts to mitigate the issue by adjusting the deposition rate have yielded minimal improvements, further complicating the situation as the economic implications and potential impacts on yield and chamber health remain uncertain.
Disadvantages
The formation of a deep racetrack groove leads to premature replacement of the Ta/TaN sputtering target, resulting in increased operational costs and waste of material that could still be utilized.
Localized erosion reduces the overall lifespan of the target, which can disrupt production schedules and lead to increased downtime for maintenance and replacement, negatively impacting overall productivity.
The uncertainty surrounding the economic implications and potential impacts on yield and chamber health complicates decision-making processes, making it difficult to justify investments in mitigation strategies or to optimize production efficiency.
Ideal final result
Achieve uniform erosion across the Ta/TaN sputtering target to maximize material utilization and extend target lifespan.
Gaps
Current magnetron magnetic-field configuration leads to localized erosion, preventing uniform utilization of the target material.
Insufficient understanding of the economic implications and potential impacts on yield and chamber health hinders decision-making for mitigation strategies.
Limited effectiveness of current mitigation attempts, such as adjusting deposition rates, restricts options for improving target lifespan and utilization.
Problem statement
The non-uniform erosion of the Ta/TaN sputtering target in Ta PVD leads to premature replacement and underutilization of expensive material, increasing operational costs and complicating production efficiency.
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