PLASMA PROCESSING DEVICE AND METHOD OF MONITORING PLASMA DISCHARGE STATE IN PLASMA PROCESSING DEVICE

摘要

An object is to provide a plasma processing device capable of rightly monitoring existence of plasma discharge and also rightly monitoring existence of abnormal discharge. Another object of the present invention is to provide a method of monitoring a state of plasma discharge in the plasma processing device. A discharge detection sensor (23), in which a dielectric member (21) and a probe electrode unit (22) are combined with each other, is attached to an opening portion (2a) provided in a lid portion (2) composing a vacuum chamber. A change in the electric potential induced in the probe electrode (22b) according to a change in plasma discharge is received, electric potential change wave-forms of specific patterns are respectively detected by an N-type wave-form detecting portion (34) and V- type wave-form detecting (35), and a discharge state judgment including a judgment of whether the electric discharge exists or does not exist and whether the electric discharge is normal or abnormal is made according to a counted value of counting the number of times of appearance of these electric potential change wave-forms for each type of wave-form by a dischargeL0N wave-form counter (36), a discharge OFF wave-form counter (37), an abnormal discharge wave-form counter (38) and a leak discharge wave-form counter (39).