摘要 |
<p>A device for use in a wafer processing chamber having a plasma forming volume and a hot edge ring. The hot edge ring has a first surface and a second surface. The first surface is in contact with the plasma forming volume. The second surface is not in contact with the plasma forming volume. The device includes a detector operable to contact the second surface of the hot edge ring. The detector can detect a parameter of the hot edge ring and can provide a detected signal based on the detected parameter.</p> |