Patent ID: 11961712
Assignee: ADVANCED ENERGY INDUSTRIES, INC.
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H | IPC H

Claim 10:
11. A match network configured for impedance matching a radio frequency power generator to a plasma processing chamber, the match network comprising:
a match input;
an output; and
a plasma return input;
a first sensor coupled to a first electrical path between the match input and the output;
a second sensor coupled to a second electrical path between the plasma return input and a ground connection;
a memory storing a first calibration matrix, K1, a second calibration matrix, K2, a first modified calibration matrix, K1′, and a second modified calibration matrix, K2′;
a controller configured to monitor power delivery to the plasma processing chamber via the first and second sensors, wherein data from the first sensor is calibrated via a first modified calibration matrix, K1′, and data from the second sensor is calibrated via a second modified calibration matrix, K2′,
wherein the modified first calibration matrix, K1′, and the modified second calibration matrix, K2′, account for errors between the first and second sensors when the first and second sensors are individually calibrated via a reference sensor and a self-load, and then mutually calibrated against each other via (1) measurements of current and voltage at the match output by the first sensor and the reference sensor or (2) measurements of current and voltage at the plasma return input by the second sensor and the reference sensor.