Re: Problem p5000etch SNF 2010-05-13 20:00:14: Cooked wafer

Replaced burnt out insulator ring and wet cleaned the chamber.
We believe the root cause of the burnt insulator and the intermittent low bias readings is the quartz clamp. The quartz clamp that we just replaced is about 1.5 mm thicker than our spare clamp. This created a gap between the insulator ring and the quartz liner (when the clamp is in the process position). I believe the gap allowed plasma to form between the ring and the quartz liner.
We ran 16 wafers with no problems.