Patent ID: 8510071

Claim:
A method for calibrating voltage values and current values detected by a high-frequency measuring device connected to a connection point between a high-frequency power supply device and a load including a plasma processing device, the high-frequency measuring device being configured to calculate an impedance as viewed from the connection point towards a load side based on the detected voltage and current values, the method comprising: a first step of calculating a first parameter based on impedances calculated when the high-frequency measuring device is connected to a first set of three reference loads and impedances of the first set of three reference loads; a second step of carrying out plasma processing by connecting the high-frequency measuring device to a load to be measured, calibrating detected voltage and current values using the first parameter, and calculating impedances as viewed from the connection point towards the load side based on the calibrated voltage and current values; a third step of determining three impedances that encompass, when displayed on a Smith chart, a narrower range than a range encompassed by the impedances of the first set of three reference loads, the narrower range including the impedances calculated in the second step; a fourth step of calculating a second parameter based on impedances calculated when the high-frequency measuring device is connected to a second set of three reference loads respectively having said three impedances and also on impedances of the second set of three reference loads; and a fifth step of connecting the high-frequency measuring device to the load to be measured and calibrating detected voltage and current values using the first parameter and the second parameter.