| 摘要 |
<p>An automatic impedance matching apparatus (10) for matching an RF-signal generator (2100) to a load (2300), such as a plasma etching chamber, is disclosed. The matching apparatus (10) comprises a matching network (20) having two variable impedance devices (231, 232), a tune detection means (40) for detecting the condition of the impedance match between the RF-signal (2100) and the load (2300) and a control means (50) for modifying the values of the variable impedance components in response to the measured tune condition. The present invention discloses improve reset and convergence means (1000) and eliminates the need for the 'dead-band'. Also disclosed is an improved adjustment means (1300) for adjusting the variable impedance components and a normalization means (1700) for normalizing the input detection signals such that variations in tuning performance due to variations in input power level from the source are substantially reduced.</p> |
