High power generator and method of supplying high power pulses

A high-power (HP) generator configured to deliver a pulsed high power with a high voltage value and/or a high current value to a capacitive load, the HP generator comprising:

• a plurality of low power (LP) generators,
• each respective LP generator comprising a respective energy storage component, wherein, during operation, the respective energy storage component is charged to a respective predefined value related to the respective energy storage component,
• each respective LP generator configured to supply, during operation, at an output thereof a respective LP-generator-value which corresponds to the respective predefined value of the respective energy storage component incorporated in the respective LP generator,
• a coupling in which the plurality of LP generators are electrically connected such that a coupling-value at an output of the coupling, which corresponds to an output value at an output of the HP generator, is obtainable, and wherein, during operation, at least in some states of the HP generator, the coupling-value is higher than the LP-generator-value at the output of one of the plurality of LP generators, and
• a control unit configured to select a respective contribution of each of the plurality of LP generators to the output value of the HP generator during power delivery of the HP generator, in order to generate a rise and/or a decay of a pulse at the output of the coupling, the control unit being configured to control the LP generators such that at least two LP generators contribute to the output of the HP generator, a sum of the LP-generator-values of the at least two LP generators that contribute to the output of the HP generator being equal to the HP output value,
• wherein more than four LP generators of the plurality of LP generators are electrically connected in the coupling, and/or
• wherein a number of LP generators electrically connected in the coupling is high enough to form, at the output of the coupling:
• pulses with a voltage rise and/or a voltage fall with values equal to or higher than a sum of the LP-generator-values of the number of LP generators, and
• a step-line pulse shape, wherein a value of a step is equal to or higher than the LP-generator-values of one or more of the number of LP generators.

A method of supplying a plasma process with high power pulses having varying amplitudes provided by a high power (HP) generator, the HP generator comprising a plurality of low power (LP) generators electrically connected in a coupling, each respective LP generator comprising a respective energy storage component, the method comprising:

• continuously charging the respective energy storage component of each respective LP generator of the plurality of LP generators to respective predefined value, and
• selectively coupling output values of at least some of the plurality of LP generators to obtain a desired output value of the HP generator corresponding to a pulse having a desired amplitude, by controlling the plurality of LP generators such that at least two LP generators contribute to the output value of the HP generator, a sum of LP-generator-values of the at least two LP generators that contribute to the output of the HP generator corresponding to the desired HP output value, and by controlling the plurality of LP generators in a way that one or a combination of following features is accomplished:
• an output of the coupling and/or an output of the HP generator is a step function, at a rising edge and/or a falling edge of the pulse, and/or during the pulse,
• the plurality of LP generators is activated sequentially during the pulse,
• at least one amplitude step is lower than 1 kV, and
• the plurality of LP generators is connected by switching only.