| 摘要 |
PROBLEM TO BE SOLVED: To provide a high-efficiency ICP high-frequency power source which is increased in response speed, by lowering the power-supply voltage while reducing the power losses in a plurality of stages of high-frequency amplifying sections. SOLUTION: High-frequency, oscillated and amplified by means of the oscillation circuit of an RF amplifier 21a of the first-stage amplifier 21, is amplified by means of an RF amplifier 21c of the amplifier 21 via a voltage-controlled attenuator 21b and inputted to the final-stage amplifier 22 via the next-stage amplifier 22. A traveling-wave power detecting signal Pf and a reflected-wave power detecting signal Pr from a power detecting section 26 are inputted to a control section 28 and the section 28 controls DC power sources, by turning on and off the power sources so that a power-supply voltage Vdd from a DC power source section 24 becomes the required lowest voltage value. At the same time, control signals are sent to the attenuator 21b and a matching section 27 so that the voltage Vdd matches a load (coil 6 or plasma) and a high-frequency current flows to the coil 6. COPYRIGHT: (C)2003,JPO
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