US Patent 9704692 System for instantaneous radiofrequency power measurement and associated methods

Each of multiple plasma processing chambers has an RF power input line connected to receive RF power from a common RF power source. An RF control module is connected to distribute RF power from the common RF power source to the RF power input lines of the multiple chambers. A voltage sensor and a current sensor are connected to a corresponding RF power input line. Each voltage sensor measures an instantaneous electrical voltage present on its RF power input line. Each current sensor measures an instantaneous electrical current present on its RF power input line. An analog multiplier module is connected to receive as inputs the instantaneous electrical voltage from its corresponding voltage sensor and the instantaneous electrical current from its corresponding current sensor. Each analog multiplier module generates an output signal that indicates an instantaneous RF power present on the corresponding RF power input line of the corresponding chamber.