| 摘要 |
<p>A method of fault identification in a plasma process powered by an RF source comprises initially determining, in respect of a given baseline plasma process, the changes in magnitude of a plurality of Fourier components of the RF source resulting from changes in a plurality of the process input parameters from their baseline values. These magnitude changes are stored as reference data. During a subsequent production run, the plasma process is monitored for faults and if one is found the baseline process is repeated with input parameter values nominally the same as the original baseline values. The changes in the Fourier components from the original baseline values are determined and compared with the reference data to determine which input parameter(s) have changed.</p> |
