Patent · US Expired

Impedance monitoring system and method

US7019543B2 · kind B2 · utility

16Cited by
10References
27Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 14, 2002
Grant dateMar 28, 2006
Priority date
Expiry dateMar 14, 2022

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02E30/10
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

An apparatus (14) for and method of measuring impedance in a capacitively coupled plasma reactor system (10). The apparatus includes a high-frequency RF source (150) in electrical communication with an upper electrode (50). A first high-pass filter (130) is arranged between the upper electrode and the high-frequency RF source, to block low-frequency, high-voltage signals from the electrode RF power source (66) from passing through to the impedance measuring circuit A current-voltage probe (140) is arranged between the high-frequency source and the high-pass filter, and is used to measure the current and voltage of the probe signal with and without the plasma present. An amplifier (250) is electrically connected to the current-voltage probe, and a data acquisition unit (260) is electrically connected to the amplifier. A second high-pass filter (276) is electrically connected to a lower electrode (56) and to ground, so as to complete the isolation of the high-frequency circuit of the impedance measurement apparatus from the low-frequency, high-voltage circuit of the capacitively coupled plasma reactor system. A method of measuring the plasma impedance using the apparatus of the prese…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.