Patent ID: 8674844
Filing Date: 2014-03-18
Classification: H01J

Abstract:
1. A method of detecting malfunction of an RF-powered plasma chamber, comprising repeatedly performing the steps of: plasma processing a set of one or more workpieces within the plasma chamber; a controller observing the minimum value and the maximum value of a first operating condition of the plasma chamber during the plasma processing of said set; the controller establishing the value of a first lower limit as equal to said minimum value of the first operating condition minus a first non-negative offset value, and establishing the value of a first upper limit as equal to said maximum value of the first operating condition plus a second non-negative offset value; after the step of plasma processing said set, cleaning one or more components of the plasma chamber; subsequently plasma processing a subsequent set of one or more workpieces within the plasma chamber; and for each respective workpiece in said subsequent set, the controller performing the steps of: