| 摘要 |
A resonance frequency can be adjusted by shifting the resonance frequency without reducing an impedance function or a withstanding voltage characteristic against a high frequency noise, when blocking, by using a multiple parallel resonance characteristic of a distributed constant line, the high frequency noise introduced into a power feed line from an electrical member other than a high frequency electrode within a processing vessel. Comb teeth M of a comb-teeth member 114 are inserted into winding gaps of air core coils 104(1) and 104(2). For example, first comb teeth M− having a thickness m− smaller than a standard thickness ts are mainly inserted in an effective zone A in a central portion of the air core coils. Further, in non-effective zones B at both sides or both end portions thereof, second comb teeth M+ having a thickness m+ equal to or larger than the standard thickness ts are arranged. |
| 主权项 |
1. A plasma processing apparatus, including an external circuit of a power meter or a signal meter electrically connected via a line to an electrical member within a processing vessel in which a plasma process is performed, configured to reduce or block a high frequency noise of a predetermined frequency introduced from the electrical member into the line toward the external circuit by a filter provided on the line,
wherein the filter comprises: an air core coil having a predetermined diameter and a predetermined length; a cylindrical external conductor, accommodating or surrounding the air core coil, configured to form, by being combined with the air core coil, a distributed constant line in which parallel resonance of multiple frequencies corresponding to multiple parallel resonance frequencies occurs; and first comb teeth and second comb teeth which are made of an insulating material and selectively inserted into winding gaps of the air core coil, wherein each of the first comb teeth has a thickness smaller than a standard thickness that allows a uniform winding gap over an entire length of the air core coil, and the first comb teeth are inserted into one or more effective zones, which are arranged separately in a lengthwise direction of the air core coil, to shift one or more of the plural parallel resonance frequencies to a lower frequency range in a frequency-impedance characteristic of the filter, and each of the second comb teeth has a thickness equal to or larger than the standard thickness and the second comb teeth are inserted into the winding gaps in which the first comb teeth are not inserted, regardless of whether the second comb teeth are provided in the one or more effective zones. |
