| 摘要 |
PROBLEM TO BE SOLVED: To provide a focus ring for significantly reducing the productive yield for a semiconductor integrated circuit and a productive yield, immediately after the usage of the focus ring by preventing failure in etching for a silicon wafer, and provide a plasma etching system, using the focus ring. SOLUTION: In the focus ring for the plasma etching system, concentration of Fe measured in secondary ion mass spectrometry is 1×103 counts or lower, and the plasma etching system using the focus ring is also provided. |
