Plasma power supply system and method

A plasma power supply system (1) for a plasma processing system (60) having a first plasma source (16ab) and a second plasma source (16cd) both in adjacent portions (6ab, 6cd) of a plasma chamber (6) in which a substrate (10, 10a, 10b) can be processed by a plasma (7) in the plasma chamber (6), the power supply system (1) comprises: a. A first power supply (2ab) configured to supply AC power to the first plasma source (16ab), b. A second power supply (2cd) configured to supply AC power to the second plasma source (16cd), c. A first sensor (28a, 28ab, 29ab) for monitoring a plasma processing parameter of the first plasma source (16ab), d. A control unit (5, 5ab, 5cd) for controlling the control unit (5, 5ab, 5cd), the control unit is configured to i. Determine first operational data relating to plasma processing parameters of the first plasma source (16ab), and ii. Control the second power source (2cd) in dependence on the operational data, in particular in order to reduce cracks on the substrate (10, 10a, 10b