Patent ID: 6714833
Filing Date: 2004-03-30
Classification: C23C,H01J

Abstract:
A performance evaluation method for a plasma processing apparatus comprising a plasma processing unit, the plasma processing unit comprising:a plasma processing chamber including an electrode for exciting a plasma; a radiofrequency generator for supplying radiofrequency power to the electrode; and a matching circuit for matching the impedances of the plasma processing chamber and the radiofrequency generator, the matching circuit having an input terminal connected to the radiofrequency generator, an output terminal connected to the electrode, and a connection point provided between the input terminal and the output terminal, the matching circuit being connected to a ground potential portion via the connection point, the performance evaluation method comprising: calculating the absolute value |&Dgr;RA| of the difference &Dgr;RA between an AC resistance RA0 at a time t0 and an AC resistance RA1 at a later time t1 in the matching circuit, the AC resistances RA0 and RA1 being measured from the input terminal side of the matching circuit; calculating the absolute value |&Dgr;RB| of the difference &Dgr;RB between an AC resistance RB0 at the time t0 and an AC resistance RB1 at the later time t1 in the matching circuit, the AC resistances RB0 and RB1 being measured from the output terminal side of the matching circuit; and determining that the plasma processing apparatus maintains a required level of performance when the absolute value |&Dgr;RA| is less than a first upper limit and when the absolute value |&Dgr;RB| is less than a second upper limit and that the plasma processing apparatus does not maintain the required level of performance when the absolute value |&Dgr;RA| is not less than the first upper limit or when the absolute value |&Dgr;RB| is not less than the second upper limit.