Abstract: Method and generator circuit for generating plasmas by means of radiofrequency excitation In order to provide a voltage that maintains the plasma, according to the method, a high-frequency voltage having a defined operating frequency and at least one further high-frequency voltage having in each case a multiple of said operating frequency and in each case an adjustable amplitude and phase are superposed in a phase-locked manner. For a corresponding generator circuit, at least two radiofrequency power generators (1 to 4) are provided, of which one (1) operates at a defined operating frequency (f) and the other(s) (2 to 4) operate(s) at in each case a multiple of said operating frequency (f). All the radiofrequency power generators (1 to 4) are coupled to one another in a phase-locked manner and the relative phase angle and also the respective amplitude of each radiofrequency power generator (1 to 4) can be individually regulated by means of a dedicated matching circuit (5 to 8).