| 摘要 |
PURPOSE: To provide the processing with high homogeneity by measuring impedance, power, current for each upper electrode so as to obtain the space deflection of plasma, and changing supplying power and phase angle. CONSTITUTION: Impedance Z, the current I flowed to the plasma, and the effective power P are measured so as to monitor a change of condition of upper electrodes 5a-5c, and the high frequency power P and the phase differenceΦare controlled. In the upper electrodes 5a-5c, a phase-shifter 8 makes a phase difference at 120 degree, and this phase difference is amplified by amplifiers 7a-7c, and given to the electrodes 5a-5c through matching boxes 6a-6c. The output impedance Za-Zc of the box 6 is monitored, and the flowed current ia-ic is monitored by current transformers 12a-12c. Powers Pa-Pc of the electrodes 5a-5c are thereby obtained. The effective power is obtained by multiplying the impedance Z by the square of the current, and the spatial turbulence of plasma is obtained. Electrical potential and phase angle are controlled for the fine adjustment, and the processing with high homogeneity can be performed.
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