DE102024114020A1 - Power supply system for supplying a plasma or gas laser process and method for operating such a power supply system - Google Patents

Abstract

Method for operating a power supply system (2), wherein the power supply system (2) comprises a power converter (3) generating an RF power signal, which is connected to a load (6) for supplying power to a plasma or gas laser process, wherein the power converter (3) comprises at least one amplifier stage (40) configured as a balanced amplifier with a first and second amplifier unit (42a, 43a), each comprising the following components:
i. a baseload amplifier (103) configured to provide a baseload amplifier power;
ii. a peak load amplifier (104) configured to provide peak load amplifier power; and
iii. a power coupler (107) for combining the base load amplifier power and the peak load amplifier power at the output of the respective first and second amplifier units to form an amplifier output power (P _out ) wherein the method comprises the following process steps:
- to generate a power boost above the rated power of the power supply system (2) an amplitude and/or phase relationship between the base load amplifier (103) and the peak load amplifier (104) of at least one of the first and second amplifier units is set such that the amplifier output power (P _out ) of the amplifier unit is greater than a rated power of the amplifier unit (42a, 43a).

Description

The invention relates to a method for operating a power supply system, wherein the power supply system comprises a power converter generating a high-frequency power signal (RF power signal) which is connected to a load for supplying power to a plasma or gas laser process. The invention further relates to a power supply system comprising a power converter designed to generate a high-frequency power signal for supplying power to a plasma or gas laser process and which is connectable to a load for this purpose.

Power supply systems, particularly those generating power at frequencies ≥ 1 MHz and especially ≤ 200 MHz and, most notably, ≤ 90 MHz, are used, for example, for laser excitation or in plasma coating systems. Such power supply systems often employ multiple amplifiers to generate the overall power output of the system.

In such a power supply system, sudden changes in the required power can occur, for example, if an arc develops in the plasma chamber and the supplied power must be abruptly reduced. Conversely, igniting a plasma may require a different power than operating a plasma process. When the plasma state changes, the load impedance also changes, resulting in another abrupt load change. Impedance matching often cannot be performed quickly enough, causing power to be reflected from the load. This reflected power should be kept away from the amplifiers and amplifier paths, if possible, to prevent damage to the power supply system. While it is known to use circulators to absorb the reflected power, in the frequency range mentioned, such circulators are extremely large due to the need for very large inductances and/or magnetic fields and are therefore not practical.

When sudden load changes or changes in the required power occur, the output power must be controlled. This can be achieved, for example, by varying the input power of an amplifier. However, this also changes the efficiency of the amplifier. At low output powers, the amplifier operates in the so-called back-off region. This is the region in which the amplifier only provides a portion of its maximum possible output power. In this back-off region, the efficiency of the amplifier decreases. Depending on the load being driven, the transistor used in the amplifier must therefore dissipate significantly more power. This causes it to heat up considerably. This behavior changes with impedance mismatch. Depending on the load angle or reflection coefficient, the transistor heats up either in the back-off or saturation region. Therefore, controlling the output power via the input power is only possible to a limited extent with impedance mismatch. To prevent the transistor from overheating, it has often been recommended to limit the maximum output power. Reducing the maximum output power does not solve this problem, however, as critical temperatures occur at low power levels and not just at high power levels when there is a large mismatch and an unfavorable load angle.

Igniting a plasma or gas laser typically requires more power than the continued operation of the ignited plasma or gas laser. Therefore, it is known to apply the full operating power to the plasma system at an increased voltage to achieve the fastest possible plasma ignition. Such systems frequently employ so-called balanced amplifiers. A balanced amplifier typically has two amplifier paths, each delivering an amplifier path output signal to a phase-shifting coupler unit. The phase-shifting coupler unit has an output terminal and an isolation terminal and is configured to combine the amplifier path output signals based on their amplitude and/or phase relationship, delivering power to the output terminal and/or the isolation terminal. The amplifier paths are typically operated with a mutual phase shift of 90°. Such balanced amplifiers and their characteristics are also described, for example, in the following publication: Alexander Alt et al.: “Analysis of high power LDMOS amplifiers for industrial applications under mismatch conditions”, published in 2014 IEEE Topical Conference on Power Amplifiers for Wireless and Radio Applications (PAWR), Electronic ISBN:978-1-4799-2778-4 . There, the term 'balanced amplifier' is used as an alternative term for 'balanced amplifier'.

For suitable balanced amplifiers designed for operation with a gas laser or plasma, the output power is essentially flat across the complex load plane, i.e., essentially constant. Power peaks or surges are difficult to detect. A pseudo-peaking effect can only be achieved by selecting a higher DC supply voltage. This briefly higher DC supply voltage allows for the generation of higher ignition power. However, generating such a high DC supply voltage for this power boost (power peak) is very complex.

With unbalanced amplifiers, especially those without a coupler, an impedance at which power amplification occurs can be selected by choosing a suitable cable length between the amplifier and the plasma chamber or discharge chamber. Unbalanced amplifiers have numerous other disadvantages, which is why they are being used less and less frequently in plasma or laser applications.

One way to ignite such a plasma or gas laser system with a balanced amplifier is, for example, in DE 10 2022 108 631 A1 The term "balanced amplifier" is also used there as an alternative designation for "balanced amplifier." For ignition and operation, the phase relationship between the amplifier paths is changed during ignition operation compared to the phase relationship during plasma processing or laser excitation operation. The method described there works very well in many systems, but not with satisfactory reliability in all systems.

Against this background, the task arises to enable reliable ignition of a plasma or gas laser and also to enable reliable and efficient operation of a power supply system with highly fluctuating, for example pulsed, power output.

• - einen ersten Verstärkerpfad, aufweisend eine erste Verstärkereinheit,
• - einen zweiten Verstärkerpfad, aufweisend eine zweite Verstärkereinheit,

wobei der erste Verstärkerpfad zum Ausgeben eines ersten Verstärkerpfadausgangssignals konfiguriert ist und der zweite Verstärkerpfad zum Ausgeben eines zweiten Verstärkerpfadausgangssignals konfiguriert ist, das eine gegenüber dem ersten Verstärkerpfadausgangssignal verschobene Phase aufweist, die ungleich, insbesondere größer, 0° ist,
wobei die Verstärkerpfade mit einer phasenlagenschiebenden Kopplereinheit verbunden sind, die ausgelegt ist, die Ausgangssignale der Verstärkerpfade zu einem Hochfrequenzleistungssignal zu koppeln,
wobei die erste und die zweite Verstärkereinheit jeweils folgende Bestandteile aufweisen:

1. i. einen Grundlast-Verstärker, der dazu eingerichtet ist, eine Grundlast-Verstärkerleistung bereitzustellen;
2. ii. einen Spitzenlast-Verstärker ist, der dazu eingerichtet ist, eine Spitzenlast-Verstärkerleistung bereitzustellen; und
3. iii. einen Leistungskoppler zum Kombinieren der Grundlast-Verstärkerleistung und der Spitzenlast-Verstärkerleistung am Ausgang der jeweiligen ersten bzw. zweiten Verstärkereinheit zu einer Verstärker-Ausgangsleistung

wobei das Verfahren folgende Verfahrensschritte umfasst:

• - zum Erzeugen einer Leistungsüberhöhung oberhalb der Nennleistung des Leistungsversorgungssystems, insbesondere zum Zünden eines Plasmas oder Gaslasers, wird eine Amplituden- und/oder Phasenbeziehung zwischen dem Grundlast-Verstärker und dem Spitzenlast-Verstärker mindestens einer der ersten und zweiten Verstärkereinheit, insbesondere kurzzeitig, derart eingestellt, dass die Verstärker-Ausgangsleistung der Verstärkereinheit größer ist als eine Nennleistung der Verstärkereinheit.

To solve the problem, a method for operating a power supply system according to claim 1 is proposed. This relates to a method for operating a power supply system, wherein the power supply system comprises a power converter generating a high-frequency power signal, which is connected to a load for supplying power to a plasma or gas laser process.
where the power converter includes at least one amplifier stage which features:

• - a first amplifier path comprising a first amplifier unit,
• - a second amplifier path, comprising a second amplifier unit,

wherein the first amplifier path is configured to output a first amplifier path output signal and the second amplifier path is configured to output a second amplifier path output signal which has a phase shift relative to the first amplifier path output signal, which is not equal to, in particular greater than, 0°,
wherein the amplifier paths are connected to a phase-shifting coupler unit designed to couple the output signals of the amplifier paths to a high-frequency power signal,
wherein the first and second amplifier units each comprise the following components:

1. i. a baseload amplifier designed to provide baseload amplifier power;
2. ii. a peak load amplifier designed to provide peak load amplification power; and
3. iii. a power coupler for combining the base load amplifier power and the peak load amplifier power at the output of the respective first or second amplifier unit to produce an amplifier output power

the procedure comprises the following procedural steps:

• - To generate a power boost above the nominal power of the power supply system, in particular to ignite a plasma or gas laser, an amplitude and/or phase relationship between the base load amplifier and the peak load amplifier of at least one of the first and second amplifier units is set, in particular briefly, such that the amplifier output power of the amplifier unit is greater than a nominal power of the amplifier unit.

"Rated power" refers to the power value for which the corresponding system or unit is designed in normal operation and to which it can be set at its maximum.

The increased power output is therefore not intended for normal operation, but only for special operation, particularly for short periods, e.g., for ignition. "Short period" here refers to the time range within which a plasma typically ignites. This depends on the characteristics of the plasma process setup. However, such a value is always no more than 1 ms.

The method for achieving a power boost can also be used for operating states other than ignition. For example, during a pulse of the amplifier output power... tung, e.g. in a multi-level pulse, one of the pulses is operated with this power increase.

Since the power loss in this type of power boost operation is generally higher than in normal operation, this power boost operation is not advantageous for continuous operation.

In one aspect, the power boost is achieved by adjusting the amplitude and/or phase relationship between the base load amplifier and the peak load amplifier in such a way that the load impedance for the base load amplifier and/or the load impedance for the peak load amplifier changes in such a way that the resulting amplifier output power of the amplifier unit is greater than a rated power of the amplifier unit.

In one aspect, during normal operation, especially for maintaining a plasma or operating a gas laser, the first and second amplifier units are operated with an amplifier output power that is less than or equal to the rated power of the amplifier unit.

A phase-shifting coupler unit is understood to be a unit comprising a coupler and, optionally, a phase-shifting network for one or more amplifier paths, wherein the input signals of the coupler unit, in normal operation, have a phase relationship to each other that is neither 0° nor 180°, and in particular is greater than 0° and less than 180°. For example, the input signals may be phase-shifted by 90°. A coupler unit whose input signals, in fully coupled operation, have a phase offset of 0° or 180° to each other is not understood as a phase-shifting coupler unit in this disclosure, since here the input signals are merely added without any further phase offset. The phase-shifting coupler unit can be a 90° hybrid coupler. This fulfills the requirements in an improved manner with reduced component count. A phase-shifting coupler unit is also understood to be a unit designed to return reflected power, which is directed from the load through the coupler to the amplifier units, to the amplifier units with different phases. For example, in the case of a mismatch, a 90° hybrid coupler, to whose input terminals two amplifier units with the same impedance are connected, will distribute the reflected power to the two amplifier units with a 90° phase shift. A phase-shifting coupler unit is also understood to be a unit that has a first input impedance at its first input terminal and a second input impedance at its second input terminal, and which is designed so that the input impedances are equal when no reflected power is directed through the coupler unit to the input terminals, and unequal when reflected power is directed through the coupler unit to the input terminals.

As described above, the coupler unit can be designed to forward the power reflected from its output terminal to its input terminals with a phase shift, thus directing it to the amplifier units in the amplifier paths. The input impedances at the coupler unit can then change, and in particular, can differ. This can result in the output impedance of the first amplifier unit having a different value than the output impedance of the second amplifier unit. This, in turn, can affect the characteristics of the coupler unit in such a way that it directs the power of one amplifier unit to the other, causing the amplifier units to interfere with each other. The output impedance of the amplifier units can become negative. Under certain load conditions, this can lead to the first amplifier unit in the first amplifier path supplying power to the second amplifier unit in the second amplifier path. These characteristics led to past discouragements against the use of phase-shifting coupler units. There were concerns that this would drive the amplifier units into unstable states and/or cause the transistors to overheat.

A common cause of instability, particularly when maintaining plasma or operating a gas laser, lies in the very rapid change in the load's impedance, e.g., that of the plasma process. This load change occurs so quickly that neither an impedance matching network connected between the power supply system and the load nor the power control system can react to it fast enough. The rapid load change produces reflected power, which is reflected back into the amplifier units. This, as described above, alters the impedance of the amplifier units. Consequently, after the rapid load change, the amplifier units no longer deliver the same power as before. However, in a power supply system with a phase-shifting coupler unit, especially a 90° hybrid coupler, the change in power per change in the load state is much smaller than in a power supply system without such a coupler unit or with non-phase-shifting characteristics. Therefore, a power supply system with a phase-shifting coupler unit is more stable.

Examples of the design of such a phase-shifting coupler unit are, for example, in WO 2017/001598 A1 , WO 2005/027258 A1 , WO 2011/110654 A1 , EP 1 699 107 A1 , DE 20 2010 016 850 U1 or DE 20 2010 016 732 U1 These disclosures are hereby incorporated in full into the present application by reference.

In one aspect, a first and a second amplifier unit are provided as part of the two amplifier paths. Both the first and second amplifier units have a design with two different sub-amplifiers, referred to here as the base-load amplifier and the peak-load amplifier. The first and second amplifier units are configured such that the base-load amplifier essentially provides a base load of the amplifier output power. The peak-load amplifier can be active at a low power level in base-load operation, where the output power is mainly provided by the base-load amplifiers, or the peak-load amplifier can be inactive. The power coupler provided as part of the first and second amplifier units combines the base-load amplifier power and the peak-load amplifier power at the output of the respective first and second amplifier units to produce a single amplifier output power. Preferably, the first and second amplifier units, i.e., the two combinations of base-load amplifier and peak-load amplifier, are each designed as Doherty amplifiers.

In one aspect, the first and second amplifier units are identical.

It has been found that the power supply system exhibits significantly lower power dissipation under impedance mismatch than known power supply systems. This can be attributed to the fact that the base-load and peak-load amplifiers of the first and second amplifier units can each operate in a highly efficient operating range, particularly during normal operation. This increases the efficiency of the first and second amplifier units compared to a conventional push-pull amplifier, especially a Class AB amplifier. Due to the reduced power dissipation, the first and second amplifier units heat up less, particularly during normal operation, thereby increasing the lifespan of the amplifier units, especially their transistors, and thus the overall reliability of the power supply system. Furthermore, the load power variation is almost independent of the load angle.

To generate the power boost above the rated power of the power supply system, the amplitude and/or phase relationship between the base-load amplifier and the peak-load amplifier of at least one amplifier unit is modified compared to normal operation, so that the amplifier output power of the respective amplifier unit is greater than its rated power. In the first and second amplifier units, the base-load and peak-load amplifiers are combined by the power coupler in such a way that they mutually modulate the load. By changing the phase relationship between the base-load and peak-load amplifiers, the direction of the load modulation can be set. By changing the amplitude relationship between the base-load and peak-load amplifiers, the magnitude of the load modulation can be set. The load modulation can pull the base-load and/or peak-load amplifiers into a load range where the amplifiers provide an output power greater than their rated power. This does have some drawbacks: On the one hand, the power dissipation of the amplifiers increases, which is acceptable for short periods, for example, in the range of one or more microseconds. On the other hand, the maximum achievable output power can be limited by a DC power supply to the base-load amplifier and the peak-load amplifier. However, this limitation can be overcome by providing a buffer capacitor or another suitable energy storage device.

The described method thus enables reliable ignition of a plasma or gas laser and also allows reliable and efficient normal operation with highly fluctuating, for example pulsed, power output.

One aspect of the design is that, to generate the power boost, an amplitude and/or phase relationship between the base-load amplifier and the peak-load amplifier of both the first and second amplifier units is adjusted, particularly briefly, such that the amplifier output power of both units exceeds the rated power of each. This design allows for particularly flexible adjustment of the power boost above the rated power of the power supply system.

One aspect of the design involves adjusting the amplitude and/or phase relationship to generate the power boost, such that the load impedance of the baseline amplifier deviates from normal operation, specifically that the load impedance of the baseline amplifier is lower than in normal operation. In such an operating state, the respective amplifier unit can generate higher output power with lower efficiency.

One aspect of the design is that, to generate the power boost, the phase relationship between the base-load amplifier and the peak-load amplifier is set to a phase difference other than 90°, preferably deviating by at least 10° from 90°, and particularly preferably by at least 20° from 90°, for example, to 120° or 60°. Setting the phase relationship between the base-load amplifier and the peak-load amplifier within this range has proven advantageous for generating the power boost. During normal operation, the phase relationship can be set to a phase difference of less than or equal to 90°. Therefore, the phase difference for generating the power boost can be increased.

One aspect of the design is that, to generate the power boost, the amplitude relationship between the base-load amplifier and the peak-load amplifier is set to a factor of at least 1.2, and in particular at least 1.4. For example, the amplitude of the base-load amplifier relative to the amplitude of the peak-load amplifier can be set to a value greater than or equal to 3 dB. Alternatively, the amplitude of the peak-load amplifier relative to the amplitude of the base-load amplifier can be set to a value greater than or equal to 3 dB. Such an amplitude relationship has proven advantageous for generating the power boost. During normal operation, the amplitude relationship can be set to a value of essentially 0 dB.

In one aspect, the power supply system is designed to include a signal generation device that provides signals to the first and second amplifier units for generating the high-frequency power signal. The signal provided during normal operation differs from the signal provided for generating the power boost. This signal generation device thus makes it possible to control the first and second amplifier units in such a way that either, particularly briefly, a power boost above the rated power is generated, or, during normal operation, an amplifier output power is provided that is less than or equal to the rated power.

Preferably, the signal supply device is configured – during normal operation – to provide signals to the first and second amplifier units for generating the high-frequency power signal within a predetermined power range such that the base-load amplifier power is greater than the peak-load amplifier power in at least a portion of the predetermined power range. In this power range, which can also be referred to as the base-load range, the base-load amplifier can thus supply the majority of the amplifier output power. The base-load amplifier preferably operates in a high-efficiency range. The peak-load amplifier provides only a small amount of power or none at all in this range, so it is not necessary for the peak-load amplifier to also operate in an efficient range within this power range. Preferably, the base-load amplifier power is greater than the peak-load amplifier power in a lower portion of the predetermined power range. Therefore, low power levels can be covered solely or mainly by the base load amplifier, without the peak load amplifier needing to be active or provide high power.

In one aspect, it is provided that the peak-load amplifier and the base-load amplifier each have an amplifying transistor with an input terminal, e.g., a gate terminal. In another aspect, it is provided that a bias voltage at the input terminal of the transistor is adjustable in at least one of the two amplifiers, and that during operation, the bias voltage of the base-load amplifier is different from that of the peak-load amplifier. In yet another aspect, it is provided that a bias current at the input terminal of the transistor is adjustable in at least one of the two amplifiers, and that during operation, the bias current of the base-load amplifier is different from that of the peak-load amplifier. A bias voltage, in this context, is understood to be a voltage that changes very slowly or not at all compared to the input signal and is designed to maintain the transistor in a predetermined conductivity state at its output terminals. A bias current, in this context, refers to a current that changes very slowly or not at all compared to the input signal and is designed to maintain the transistor in a predetermined conductivity state at its output terminals. A typical gate-bias arrangement is, for example, in WO 2017/001594 A1 revealed. WO 2017/001594 A1 is hereby fully incorporated into the present application by reference.

In one aspect, the base-load amplifier is configured as an essentially linear amplifier, and the peak-load amplifier as an essentially non-linear amplifier. The base-load amplifier behaves essentially linearly, particularly in a power range where its power output is greater than its power output; that is, its output signal is proportional to its input signal. The peak-load amplifier, on the other hand, can be configured such that its output signal is not proportional to its input signal. The aforementioned bias voltage and/or bias current settings can be used for this purpose.

In one aspect, the peak-load amplifier and/or the base-load amplifier are designed as push-pull power amplifiers. Specifically, the peak-load amplifier and/or the base-load amplifier each have two identical transistors. In particular, the two identical transistors are housed in a common package. In another aspect, the peak-load amplifier and/or the base-load amplifier are designed as planar power amplifiers, specifically in a configuration such as that found, for example, in WO 2017/001602 A1 is described. WO 2017/001602 A1 is hereby fully incorporated into the present application by reference.

One aspect of the design is that the base-load amplifier is configured as either a Class B or Class AB amplifier, and the peak-load amplifier is configured as a Class C amplifier. In either the Class B or Class AB configuration, the base-load amplifier can comprise two transistors arranged in a push-pull configuration. In a Class B amplifier, each transistor conducts for 180° of a oscillation period. A Class B amplifier can achieve an efficiency of up to 78.5%, but exhibits some distortion due to the switching transition between the two transistors. In a Class AB amplifier, however, each transistor conducts for more than 180° of a oscillation period, thus creating an overlap region in which both transistors conduct. Class AB amplifiers sacrifice some of the efficiency of a Class B amplifier but achieve improved linearity. A Class C amplifier has one or more transistors that conduct for less than 180° of the oscillation period, for example, approximately 120°. Class C amplifiers exhibit high signal distortion but can achieve high efficiency, for example, around 80%. The previously mentioned bias voltage and/or bias current settings can be used to adjust these amplifier classes.

One aspect of the design is that the peak-load amplifier—during normal operation—is configured to provide peak-load amplification power only when a predetermined base-load amplification power is exceeded. The aforementioned bias voltage and/or bias current at the input of the peak-load amplifier's amplifying transistor can be used for this purpose. This design offers the advantage that the base-load amplifier alone provides the amplifier output power within a base-load range. Therefore, the behavior of the first and second amplifier units within this range can be essentially controlled by the base-load amplifier. Only when a higher power than the base load is required does the peak-load amplifier become active and provide peak-load amplification power in addition to the base-load amplification power. Thus, the peak-load amplifier can, in particular, compensate for power surges.

One aspect is that the peak load amplifier - in normal operation - is designed to change the output impedance of the peak load amplifier so that it is high-impedance when a predetermined base load amplifier power is undershot.

In one aspect, it is provided that the power supply system has a signal provision device which is configured to provide signals to the first and second amplifier units for generating the high-frequency power signal in such a way that an output signal of the peak load amplifier has a phase shift relative to an output signal of the base load amplifier, and/or
The first and second amplifier units each include a phase-shifting splitter configured to supply signals to the base-load amplifier and the peak-load amplifier for generating the high-frequency power signal such that the peak-load amplifier's output signal has a phase shift relative to the base-load amplifier's output signal. This phase shift between the peak-load and base-load amplifier output signals allows the use of a phase-shifting power coupler as part of the first and second amplifier units.

In one aspect, the signal generation device or the phase-shifting splitter is designed so that the phase offset, especially during normal operation, is adjustable, particularly to a value of 90° or n*180° + 90°. Examples of the design of such a phase-shifting splitter are, for example, in WO 2017/001598 A1 , revealed.

In one aspect, the power coupler is designed as a phase-shifting power coupler. This allows the phase-shifting power coupler to combine two output signals from the base-load amplifier and the peak-load amplifier with a phase offset in a phase-correct manner. The phase-shifting power coupler can include an impedance converter and/or a λ/4 line, particularly one arranged between the output of a base-load amplifier and a peak-load amplifier and the output of the first or second amplifier unit. The power coupler can be constructed from discrete components, particularly a combination of inductance(s) and capacitor(s), preferably a network with two capacitors connected to ground and an inductor connected between the other two terminals of the capacitors and connected to the input or output of the power coupler. The inductor can be implemented as a planar inductor on a printed circuit board. One or both capacitances can be at least partially determined by the capacitance of the planar inductor to ground. Impedance matching can be achieved via the impedance converter, which increases the efficiency of the first and second amplifier stages.

One aspect is that the power coupler increases the output impedance at its output relative to the output impedance of the base load amplifier when the base load amplifier is operated in overdrive.

One aspect is that the base load amplifier has a higher output impedance when operated in the linear range than when operated in overdrive.

One aspect is that the peak load amplifier has a higher output impedance when the base load amplifier is operated in the linear range than when the base load amplifier is operated in overdrive.

One aspect of the design is that the phase shift of the second amplifier path output signal relative to the first amplifier path output signal is adjustable. Adjusting the phase allows the output power of the power converter to be controlled. Furthermore, it is possible to increase the output power to generate the power boost above the rated power. The phase adjustment between the first and second amplifier path output signals can be achieved by a signal generation device configured to provide signals to the first and second amplifier units for generating the high-frequency power signal, or by an adjustable splitter connected to the first and second amplifier units.

One aspect of the design is that the amplifiers and/or amplifier units each incorporate one or more transistors, particularly LDMOS or GaN transistors. LDMOS stands for "laterally diffused metal oxide semiconductor." When used in amplifiers or amplifier units to generate power suitable for plasma processes, these LDMOS transistors have proven to be significantly more reliable than comparable conventional MOSFETs. This can be attributed to their much higher current handling capability. LDMOS transistors allow for the construction of amplifiers, amplifier units, and power supply systems with a very similar or even identical topology, suitable for use at frequencies spanning several decades in the range of 1 MHz to 200 MHz, preferably in the range of 1 MHz to 90 MHz. These are frequencies commonly used in plasma processes and for gas laser excitation. Conventional MOSFETs often struggle with plasma processes at these frequencies when too much power supplied to the process is reflected back. Therefore, the generated power often had to be limited to prevent the reflected power from exceeding a critical threshold. This made it difficult to reliably ignite the plasma processes or operate them within the desired power range. Furthermore, complex, adjustable impedance matching circuits and combiners were required to overcome these drawbacks. LDMOS transistors are particularly advantageous when significant reflected power is expected, as is the case, for example, when powering plasma processes. In conjunction with the aforementioned phase-shifting coupler unit, the advantage of LDMOS transistors lies in their ability to handle much higher levels of reflected power. This reduces the requirements for additional impedance matching networks connected between the power supply system and the load, thus saving on component and control network costs. Examples of the design of a previously mentioned phase-shifting power coupler and an amplifier with LDMOS transistors are, for example, in WO2015/091468A1 This disclosure is hereby incorporated in its entirety into the present application by reference.

One aspect of the design involves multiple amplifier stages, with each pair of amplifier paths connected directly to a 90° hybrid coupler, without the need for any other coupling devices. This configuration allows for higher power output.

In one aspect, the power supply system is configured such that, in the event of a load mismatch, power reflected from the load is at least partially routed via the coupler unit and at least one power coupler to at least one base-load amplifier and one peak-load amplifier, at least partially reflected by these amplifiers, and then returned via the at least one power coupler to the coupler unit, which at least partially dissipates this returned power into a resistor. Preferably, a larger proportion of the power is reflected by the base-load amplifier than by the respective peak-load amplifier.

In one aspect, it is provided that several of the amplifier stages disclosed herein are connected in parallel and the output terminals of these parallel amplifier stages are interconnected via a power coupler cascade or multiple combiner. Examples of such a power coupler cascade or multiple combiner are, for example, in WO 2011/110652 A1 , WO 2017/001595 A1 , DE 10 2011 086 557 A1 or EP 1 701 376 A1 as well as DE 10 2023 111 812 A1 These disclosures are hereby incorporated in full into the present application by reference.

• - einen ersten Verstärkerpfad, aufweisend eine erste Verstärkereinheit,
• - einen zweiten Verstärkerpfad, aufweisend eine zweite Verstärkereinheit,
  • wobei der erste Verstärkerpfad zum Ausgeben eines ersten Verstärkerpfadausgangssignals konfiguriert ist und der zweite Verstärkerpfad zum Ausgeben eines zweiten Verstärkerpfadausgangssignals konfiguriert ist, das eine gegenüber dem ersten Verstärkerpfadausgangssignal verschobene Phase aufweist, die ungleich, insbesondere größer, 0° und ungleich, insbesondere kleiner, 180° ist,
  • wobei die Verstärkerpfade mit einer phasenlagenschiebenden Kopplereinheit verbunden sind, die ausgelegt ist, die Ausgangssignale der Verstärkerpfade zu einem Hochfrequenzleistungssignal zu koppeln,

wobei die erste und die zweite Verstärkereinheit jeweils folgende Bestandteile aufweisen:

1. i. einen Grundlast-Verstärker, der dazu eingerichtet ist, eine Grundlast-Verstärkerleistung bereitzustellen;
2. ii. einen Spitzenlast-Verstärker ist, der dazu eingerichtet ist, eine Spitzenlast-Verstärkerleistung bereitzustellen; und
3. iii. einen Leistungskoppler zum Kombinieren der Grundlast-Verstärkerleistung und der Spitzenlast-Verstärkerleistung am Ausgang der jeweiligen ersten bzw. zweiten Verstärkereinheit zu einer Verstärker-Ausgangsleistung,

wobei das Leistungsversorgungssystems (2) konfiguriert ist

• - zum Erzeugen einer Leistungsüberhöhung oberhalb der Nennleistung des Leistungsversorgungssystems, insbesondere zum Zünden eines Plasmas oder Gaslasers, wobei eine Amplituden- und/oder Phasenbeziehung zwischen dem Grundlast-Verstärker und dem Spitzenlast-Verstärker mindestens einer der ersten und zweiten Verstärkereinheit, insbesondere kurzzeitig, derart einstellbar ist, dass die Verstärker-Ausgangsleistung der Verstärkereinheit größer ist als eine Nennleistung der Verstärkereinheit; und, bevorzugt
• - zu einem Normalbetrieb, insbesondere zum Aufrechterhalten eines Plasmas oder Betreiben eines Gaslasers, bei dem die erste und zweite Verstärkereinheit mit einer Verstärker-Ausgangsleistung, die kleiner oder gleich der Nennleistung der Verstärkereinheit ist, betreibbar sind.

To solve the aforementioned problem, a power supply system is further proposed, comprising a power converter designed to generate a high-frequency power signal for the power supply of a plasma or gas laser process and which can be connected to a load for this purpose.
where the power converter includes at least one amplifier stage which features:

• - a first amplifier path comprising a first amplifier unit,
• - a second amplifier path, comprising a second amplifier unit,
  • wherein the first amplifier path is configured to output a first amplifier path output signal and the second amplifier path is configured to output a second amplifier path output signal which has a phase shift relative to the first amplifier path output signal, which is not equal to, in particular greater than, 0° and not equal to, in particular less than, 180°,
  • wherein the amplifier paths are connected to a phase-shifting coupler unit designed to couple the output signals of the amplifier paths to a high-frequency power signal,

wherein the first and second amplifier units each comprise the following components:

1. i. a baseload amplifier designed to provide baseload amplifier power;
2. ii. a peak load amplifier designed to provide peak load amplification power; and
3. iii. a power coupler for combining the base load amplifier power and the peak load amplifier power at the output of the respective first and second amplifier units to form an amplifier output power,

wherein the power supply system (2) is configured

• - for generating a power boost above the rated power of the power supply system, in particular for igniting a plasma or gas laser, wherein an amplitude and/or phase relationship between the base load amplifier and the peak load amplifier of at least one of the first and second amplifier units is adjustable, particularly briefly, such that the amplifier output power of the amplifier unit is greater than a rated power of the amplifier unit; and, preferably
• - to normal operation, in particular to maintain a plasma or operate a gas laser, in which the first and second amplifier units can be operated with an amplifier output power that is less than or equal to the rated power of the amplifier unit.

A phase shift between the base-load amplifier and the peak-load amplifier can be achieved using a phase shifter. Examples of possible designs for such a phase shifter are described below.

1. a. ein Leistungsversorgungssystem wie zuvor und nachfolgend beschrieben,
2. b. eine Last, insbesondere ausgebildet als Plasma- oder Gaslaserprozess,
   • • wobei das Leistungsversorgungssystem einen Leistungswandler aufweist, der an ein Spannungsversorgungsnetz angeschlossen werden kann
   • • wobei der Leistungswandler an die Last angeschlossen ist,
   • • wobei insbesondere zwischen der Last und dem Leistungswandler ein Impedanzanpassungsnetzwerk angeordnet ist.

Also revealed is a plasma system, exhibiting

1. a. a benefit provision system as described above and below,
2. b. a load, in particular designed as a plasma or gas laser process,
   • • wherein the power supply system includes a power converter that can be connected to a power supply network
   • • where the power converter is connected to the load,
   • • wherein, in particular, an impedance matching network is arranged between the load and the power converter.

Alternatively or in addition to the advantageous embodiments explained above, the advantageous embodiments and features explained in connection with the device according to the invention can be used in the method.

• 1 ein Plasmasystem mit einer detaillierten Ansicht der Verstärkeranordnung gemäß einem Ausführungsbeispiel in einem Blockdiagramm;
• 2 ein Plasmasystem mit einer detaillierten Ansicht des Leistungsversorgungssystems gemäß einem Ausführungsbeispiel in einem Blockdiagramm;
• 3 einen DDS-Baustein in einem Blockdiagramm;
• 4 ein Ausführungsbeispiel einer Verstärkereinheit des Leistungsversorgungssystems nach 1 oder 2:
• 5 eine alternatives Ausführungsbeispiel einer Verstärkerstufe für das Leistungsversorgungssystem nach 1 oder 2;

Further details and advantages of the development will be explained below with reference to the exemplary embodiments shown in the figures. These show:

• 1 a plasma system with a detailed view of the amplifier arrangement according to an exemplary embodiment in a block diagram;
• 2 a plasma system with a detailed view of the power supply system according to an exemplary embodiment in a block diagram;
• 3 a DDS component in a block diagram;
• 4 an embodiment of an amplifier unit of the power supply system according to 1 or 2 :
• 5 an alternative embodiment of an amplifier stage for the power supply system according to 1 or 2 ;

The 1 Figure 1 shows a plasma system 1, which includes a power supply system 2. The power supply system 2, in turn, has a power converter 3, which can be connected to a power supply network 4. The power converter 3 has an amplifier stage 40. The power generated at the output of the power converter is supplied via an impedance matching network 5 to a load 6, which can be, for example, a plasma chamber in which a plasma is generated, which can then be used to perform plasma processing in the plasma chamber. In particular, a workpiece can be etched or a material layer can be applied to a substrate. The load 6 can also be a gas laser excitation.

A comparable power supply system and a method for stimulating a plasma are, for example, in the DE 10 2013 226 537 A1 This power supply system discloses that two amplifier paths are connected to a phase-shifting coupler unit, which couples the output signals of the amplifier paths into a high-frequency power signal. The advantage of using a phase-shifting coupler unit is that, in the event of a mismatch, the two amplifier paths connected to the coupler unit "see" different impedances. "Seeing" impedances means that an amplifier path is connected to an impedance at its output. Since power is reflected back to the amplifier path depending on the impedance, the person skilled in the art says that the amplifier path "can see" the impedance. Because the amplifier paths "see" different impedances, the transistors of the amplifiers and/or amplifier units heat up to different temperatures in the event of a mismatch, unlike in in-phase combination. The warmer of the two transistors heats up less, even without regulation of the supply voltage, compared to the use of conventional combiners. Furthermore, in the event of a mismatch, power is not returned to the amplifier paths but can be dissipated into an absorption resistor.

• - einen ersten Verstärkerpfad 42, aufweisend eine erste Verstärkereinheit 42a und
• - einen zweiten Verstärkerpfad 43, aufweisend eine zweite Verstärkereinheit 43a.

In the lower part of 1 Amplifier stage 40 is shown in a detailed view. Amplifier stage 40 features:

• - a first amplifier path 42, comprising a first amplifier unit 42a and
• - a second amplifier path 43, comprising a second amplifier unit 43a.

An output network 45, 46 is optionally provided at the output of each of the amplifier paths 42, 43.

The first amplifier path 42 is configured to output a first amplifier path output signal, and the second amplifier path 43 is configured to output a second amplifier path output signal.

The second amplifier path output signal has a phase shift relative to the first amplifier path output signal, which is not equal to, in particular greater than, 0°.

The amplifier paths 42, 43 are connected to a phase-shifting coupler unit 47.

The phase-shifting coupler unit 47 is designed to adjust the output signals of the amplifier to couple kerpaths 42, 43 to a high-frequency power signal.

• • einen Grundlast-Verstärker 103, der dazu eingerichtet ist, eine Grundlast-Verstärkerleistung bereitzustellen;
• • einen Spitzenlast-Verstärker 104, der dazu eingerichtet ist, eine Spitzenlast-Verstärkerleistung bereitzustellen; und
• • einen Leistungskoppler 107 zum Kombinieren der Grundlast-Verstärkerleistung und der Spitzenlast-Verstärkerleistung am Ausgang der jeweiligen ersten Verstärkereinheit 42a bzw. zweiten Verstärkereinheit 43a zu einer Verstärker-Ausgangsleistung P_out.

The first amplifier unit 42a and the second amplifier unit 43a each have the following components:

• • a baseload amplifier 103, which is configured to provide a baseload amplifier power;
• • a peak load amplifier 104, which is configured to provide peak load amplifier power; and
• • a power coupler 107 for combining the base load amplifier power and the peak load amplifier power at the output of the respective first amplifier unit 42a or second amplifier unit 43a to a single amplifier output power P _out .

This phase relationship shift can be achieved, for example, by the signal generation device 99. In that case, a signal influencer 102 would be designed as a phase shifter, typically implemented digitally, i.e., in digital hardware and/or software.

This phase relationship shift can also be achieved, for example, by an analog signal influencer 102 designed as a phase shifter. This can be provided within the amplifier unit 42a, 43a.

To generate a power boost above the rated power of the power supply system 2, the amplitude and/or phase relationship between the base-load amplifier 103 and the peak-load amplifier 104 is adjusted such that a load impedance 106 for the base-load amplifier 103 and/or a load impedance 108 for the peak-load amplifier 104 changes such that the resulting amplifier output power P _{out of} the amplifier unit 42a, 43a is greater than the rated power of the amplifier unit 42a, 43a. The load impedances 106, 108 are in 1 and 5 The information shown is only for amplifier unit 43a, but it also applies analogously to amplifier unit 43a. Further details on power converter 3 and amplifier stage 40 are given below in connection with 2 , 4 and 5 described.

The 2 Figure 2 shows a schematic representation with further details of the power supply system 2. The power supply system 2 includes a power converter 3 that generates an output power which can be supplied to the load 6, for example, a plasma process or laser excitation. An impedance matching network 5 can be arranged between the load 6 and the power converter 3.

• • einen Signaldatenspeicher, in dem Signaldatenwerte zur Erzeugung der Analogsignalform abgelegt sind,
• • einen Amplitudendatenspeicher, in dem Amplitudendatenwerte zur Beeinflussung der Amplitude der Analogsignale abgelegt sind,
• • einen Multiplikator zur Multiplikation der Signaldatenwerte mit den Amplitudendatenwerten und
• • einen Zähler, der dafür sorgt, dass in einem vorbestimmten Takt Signaldatenwerte aus dem Signaldatenspeicher ausgelesen und dem Multiplikator zugeführt werden.

The power supply system 2 includes a digital-to-analog converter (DAC) 31 for generating an analog output signal. The generation of the analog signal will be described below using the diagram in 3 The following will be explained. A logic circuit unit 32 is associated with the digital-to-analog converter 31. In particular, sequences of digital values are supplied to the DAC 31 from the logic circuit unit 32, from which the DAC 31 generates the analog output signal. The DAC 31 and the logic circuit unit 32 can be integrated in a so-called direct synthesis device (DDS device) 33, which can also be referred to as a direct digital synthesizer. According to the exemplary embodiment, the logic circuit unit 32 comprises:

• • a signal data storage device in which signal data values for generating the analog signal shape are stored,
• • an amplitude data storage device in which amplitude data values are stored to influence the amplitude of the analog signals,
• • a multiplier for multiplying the signal data values by the amplitude data values and
• • a counter that ensures that signal data values are read from the signal data memory and fed to the multiplier at a predetermined rate.

Both the signal data storage 34 and the amplitude data storage 35 can be configured as so-called look-up tables (LUTs).

As in 2 As shown, the generated analog signal is fed to a first amplifier stage 40 and, in particular, to a splitter 41. The splitter 41 can be implemented as a hybrid coupler, which splits the analog signal into two phase-shifted signals, specifically two signals phase-shifted by 90°, with each signal output by the splitter 41 being fed to an amplifier path 42, 43. The first amplifier path 42 has at least one first amplifier unit 42a. The second amplifier path 43 has at least one second amplifier unit 43a. The amplifier units 42a, 43a are designed here as Doherty amplifiers, the construction of which will be discussed further below. The amplifier paths 42, 43, and thus the amplifier units 42a, 43a, are supplied with power via a power supply 44. Optionally, an output network 45, 46 is provided at the output of each amplifier path 42, 43, which adapts the output impedance of the respective amplifier unit 42a, 43a to the input impedance of a phase-shifting coupler unit 47 and simultaneously The desired Oberfellen filter is used. In the phase-shifting coupler unit 47, the output signals of the amplifier paths 42, 43 are coupled phase-dependently to form an output signal, which is ultimately fed to the load 6 via an optional impedance matching network 5. Preferably, the phase-shifting coupler unit 47 is a 90° hybrid coupler. In this respect, the first amplifier stage 40 is designed as a balanced amplifier.

The output power at the output of the coupler unit 47 can be measured by appropriate measuring instruments 48. The dashed line 49 indicates that the measuring instruments 48 are connected to a voltage regulator 50, which in turn controls the power supply 44. In particular, the measuring instruments 48 can also measure the power delivered to the load 6 and the power reflected by the load 6. From these values, a reflection coefficient or the magnitude of a reflection coefficient can be determined, which can then be used to control the voltage regulation.

• ▪ einen Grundlast-Verstärker 103, der dazu eingerichtet ist, eine Grundlast-Verstärkerleistung bereitzustellen;
• ▪ einen Spitzenlast-Verstärker 104, der dazu eingerichtet ist, eine Spitzenlast-Verstärkerleistung bereitzustellen; und
• • einen Leistungskoppler 107 zum Kombinieren der Grundlast-Verstärkerleistung und der Spitzenlast-Verstärkerleistung am Ausgang der jeweiligen ersten bzw. zweiten Verstärkereinheit 42a, 43a zu einer Verstärker-Ausgangsleistung P_out.

The representation in 4 shows a first embodiment of the two amplifier units 42a, 43a made of 2 The amplifier units 42a and 43a are designed here as Doherty amplifiers, each comprising the following components:

• ▪ a baseload amplifier 103, which is configured to provide a baseload amplifier power;
• ▪ a peak load amplifier 104, which is configured to provide peak load amplifier power; and
• • a power coupler 107 for combining the base load amplifier power and the peak load amplifier power at the output of the respective first or second amplifier unit 42a, 43a to a single amplifier output power P _out .

The power P _at the input of the first and second amplifier units 42a and 43a, respectively, is split into two signal paths with a phase shift, here a phase shift of 90°, by a phase-shifting splitter 101. The representation in 4 The functional elements of the phase-shifting splitter 101 are shown as separate elements: splitter 101 and signal influencer 102. This signal influencer 102 can be configured as a phase shifter. Additionally or alternatively, this signal influencer 102 can be configured as an amplitude influencer, i.e., for example, a signal amplifier or attenuator. However, the phase-shifting splitter 100 can also be configured as a hybrid coupler, in particular a 90° hybrid coupler. Due to the introduced phase shift, the output signal of the peak load amplifier 104 also exhibits a phase shift relative to the output signal of the base load amplifier 103. These output signals are combined by the power coupler 107. The power coupler 107 is also shown here as a combination of a phase-shifting impedance inverter 105, for example, a λ/4 line, and an impedance converter 116.

The first and second amplifier units 42a and 43a are configured such that the base-load amplifier 103 essentially provides a base load of the amplifier output power P_{_out}. In a base-load operation where the amplifier output power P_{_out} is mainly provided by the base-load amplifier 103, the peak-load amplifier 104 can be active at a low power level, or the peak-load amplifier 104 can be inactive, i.e., high-impedance. The base-load amplifier 103 can be configured as a class B or class AB amplifier, while the peak-load amplifier 104 is configured as a class C amplifier. The peak-load amplifier 104 can be designed such that its transistor(s) are conducting for only a fraction of half a signal period. Therefore, the peak load amplifier 104 is designed to provide the peak load amplifier power only when a predetermined base load amplifier power is exceeded.

The representation in 5 Figure 40 shows a further embodiment of an amplifier stage 40 comprising a first amplifier path 42 and a first amplifier unit 42a, and a second amplifier path 43 and a second amplifier unit 43a. The two amplifier units 42a and 43a are coupled to each other via a phase-shifting coupler unit 47. This coupler unit is configured here as a 3 dB 90° hybrid coupler. The two amplifier units 42a and 43a, in particular their base-load amplifier 103 and peak-load amplifier 104, are controlled by a signal generation device 99. This signal generation device is preferably configured to provide signals for generating the high-frequency power signal within a predetermined power range such that the base-load amplifier power is greater than the peak-load amplifier power at least in a portion of the predetermined power range, preferably in a lower portion of the predetermined power range.

The power supply system comprising amplifier stage 40 is configured such that, in the event of a mismatch of the load 6, power reflected from the load 6 is at least partially transferred via the coupler unit 47 and at least one power coupler 107 to at least one of the base load supplies. The power is directed to the base-load amplifier 103 and the peak-load amplifier 104. The power is reflected at least at this base-load amplifier 103 or peak-load amplifier 104 and returned via the power coupler 107 to the coupler unit 47. This unit is connected to an absorption resistor 110, which absorbs this returned power.

To ensure both reliable ignition of the plasma or gas laser and, likewise, reliable and efficient operation after ignition, even with highly fluctuating, for example pulsed, power output, special precautions have been taken in the power supply system according to the embodiments described above. As already explained above with reference to the 1 to 5 As explained, the power supply system 2 is configured to operate the first and second amplifier units 42a, 43a with an amplifier output power P _out that is less than or equal to the rated power of the respective amplifier unit 42a, 43a during normal operation, in particular for maintaining a plasma or operating a gas laser.

In addition, it is provided that the power supply system 2 is also configured to generate a power boost above the nominal power of the power supply system 2, in particular for igniting a plasma or gas laser, wherein an amplitude and/or phase relationship between the base load amplifier 103 and the peak load amplifier 104 of at least one of the first and second amplifier units 42a, 43a is adjustable, in particular briefly, such that the amplifier output power P _{out of} the amplifier unit 42a, 43a is greater than the nominal power of the respective amplifier unit 42a, 43a.

In a Doherty amplifier, the peak-load amplifier 104 modulates the load impedance of the base-load amplifier 104. To generate the power boost, the phase and/or amplitude relationship between the base-load amplifier 103 and the peak-load amplifier 104 can be altered, thereby briefly influencing the load impedance so that the overall amplifier produces an output power exceeding its rated power. This may reduce efficiency, but this is acceptable for short periods.

For example, the phase relationship in one or both amplifier units 42a, 43a can be set to a phase difference of greater than 90°, preferably greater than 100°, particularly preferably greater than 110°, for example 120°.

Under normal operating conditions, the phase relationship is usually 90°, so it is increased to generate the power boost.

Alternatively or additionally, the amplitude relationship in one or both amplifier units 42a, 43a can be set to a value greater than or equal to 3dB.

This amplitude relationship shift can be achieved, for example, by the signal supply device 99. In that case, a signal influencer 102 would be designed as an amplitude influencer, typically implemented digitally, i.e., in digital hardware and/or software.

This amplitude relationship shift can also be achieved, for example, by an analog signal influencer 102, designed as an amplitude influencer. This can be provided within the amplifier unit 42a, 43a.

The signal influencer 102 can be designed to be switched on and off.

The signal influencer 102 can be designed to be adjustable, in particular by means of an electrical signal.

The time period for generating the power boost can range from 2 microseconds to 100 microseconds.

Since two of these Doherty amplifiers are connected together with a 3dB coupler in the present power supply system, it is possible to combine the ability to provide a power boost with highly efficient normal operation with a balanced amplifier, i.e., cable length independence.

QUOTES INCLUDED IN THE DESCRIPTION

This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions.

Cited patent literature

• DE 10 2022 108 631 A1 [0008]
• WO 2017/001598 A1 [0020, 0039]
• WO 2005/027258 A1 [0020]
• WO 2011/110654 A1 [0020]
• EP 1 699 107 A1 [0020]
• DE 20 2010 016 850 U1 [0020]
• DE 20 2010 016 732 U1 [0020]
• WO 2017/001594 A1 [0032]
• WO 2017/001602 A1 [0034]
• WO 2015/091468A1 [0045]
• WO 2011/110652 A1 [0048]
• WO 2017/001595 A1 [0048]
• DE 10 2011 086 557 A1 [0048]
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• DE 10 2023 111 812 A1 [0048]
• DE 10 2013 226 537 A1 [0055]

Cited non-patent literature

• Alexander Alt et al.: “Analysis of high power LDMOS amplifiers for industrial applications under mismatch conditions”, published in 2014 IEEE Topical Conference on Power Amplifiers for Wireless and Radio Applications (PAWR), Electronic ISBN:978-1-4799-2778-4 [0005]

Claims (15)

Method for operating a power supply system (2), wherein the power supply system (2) comprises a power converter (3) generating a high-frequency power signal, which is connected to a load (6) for supplying power to a plasma or gas laser process, wherein the power converter (3) comprises at least one amplifier stage (40) comprising: - a first amplifier path (42), comprising a first amplifier unit (42a), - a second amplifier path (43), comprising a second amplifier unit (43a), wherein the first amplifier path (42) is configured to output a first amplifier path output signal and the second amplifier path (43) is configured to output a second amplifier path output signal having a phase shift relative to the first amplifier path output signal, which is not equal to, in particular greater than 0°, wherein the amplifier paths (42, 43) are connected to a phase-shifting coupler unit (47) configured to convert the output signals of the amplifier paths (42, 43) into a to couple a high-frequency power signal, wherein the first and second amplifier units (42a, 43a) each comprise the following components: i. a base-load amplifier (103) configured to provide base-load amplifier power; ii. a peak-load amplifier (104) configured to provide peak-load amplifier power; and iii. a power coupler (107) for combining the base load amplifier power and the peak load amplifier power at the output of the respective first or second amplifier unit (42a, 43a) to a single amplifier output power (P _out ) wherein the method comprises the following process step: - to generate a power boost above the nominal power of the power supply system (2), an amplitude and/or phase relationship between the base load amplifier (103) and the peak load amplifier (104) of at least one of the first and second amplifier units (42a, 43a) is set, in particular briefly, such that the amplifier output power (P _out ) of the amplifier unit (42a, 43a) is greater than a nominal power of the amplifier unit (42a, 43a). Procedure according to Claim 1 , characterized in that the power boost is realized by adjusting the amplitude and/or phase relationship between the base load amplifier (103) and the peak load amplifier (104) such that the load impedance (106) for the base load amplifier (103) and/or the load impedance (108) for the peak load amplifier (104) changes such that the resulting amplifier output power (P _out ) of the amplifier unit (42a, 43a) is greater than a rated power of the amplifier unit (42a, 43a). Method according to one of the preceding claims, characterized in that in normal operation, in particular for maintaining a plasma or operating a gas laser, the first and second amplifier unit (42a, 43a) are operated with an amplifier output power (Pout) that is less than or equal to the nominal power of the amplifier unit (42a, 43a). Method according to one of the preceding claims, characterized in that, to generate the power boost, an amplitude and/or phase relationship between the base load amplifier (103) and the peak load amplifier (104) of both the first amplifier unit (42a) and the second amplifier unit (43a) is set, in particular briefly, such that the amplifier output power (P _out ) of both amplifier units (42a, 43a) is greater than a nominal power of the respective amplifier unit (42a, 43a). Method according to one of the preceding claims, characterized in that, to generate the power boost, the amplitude and/or phase relationship is adjusted such that the load impedance (106) of the base load amplifier (103) deviates from normal operation, in particular the load impedance (106) of the base load amplifier (103) is lower than in normal operation. Method according to one of the preceding claims, characterized in that, to generate the power boost, the phase relationship between the base load amplifier (103) and the peak load amplifier (104) is set to a phase difference other than 90°, preferably deviating by at least 10° from 90°, particularly preferably deviating by at least 20° from 90°, for example to 60° or 120°. Method according to one of the preceding claims, characterized in that, to generate the power increase, the amplitude relationship between the base load amplifier (103) and the peak load amplifier (104) is set to a factor of at least 1.2, in particular at least 1.4. Method according to one of the preceding claims, characterized in that the power supply system (2) has a signal readiness comprising a setting device (99) which provides signals to the first and second amplifier units (42a, 43a) for generating the high-frequency power signal, wherein the signal provided for normal operating mode differs from the signal provided for generating the power boost. Method according to one of the preceding claims, characterized in that the base load amplifier (103) is configured as a substantially linear amplifier and the peak load amplifier (104) is configured as a substantially non-linear amplifier. Method according to one of the preceding claims, characterized in that the base load amplifier (103) is configured as a class B amplifier or as a class AB amplifier and the peak load amplifier (104) is configured as a class C amplifier. Method according to one of the preceding claims, characterized in that the peak load amplifier (104) - in normal operation - is configured to provide the peak load amplifier power only when a predetermined base load amplifier power is exceeded. Method according to one of the preceding claims, characterized in that the peak load amplifier (104) is configured in normal operation to change the output impedance of the peak load amplifier (104) such that it is high-impedance when a predetermined base load amplifier power is undershot. A method according to one of the preceding claims, characterized in that the power supply system (2) comprises a signal provision device (99) configured to provide signals to the first and second amplifier units (42a, 43a) for generating the high-frequency power signal such that an output signal of the peak load amplifier (104) has a phase shift relative to an output signal of the base load amplifier (103), and/or the first and second amplifier units (42a, 43a) comprise a phase-shifting splitter (100) configured to provide signals to the base load amplifier (103) and the peak load amplifier (104) for generating the high-frequency power signal such that an output signal of the peak load amplifier (104) has a phase shift relative to an output signal of the base load amplifier (103). Power supply system (2) comprising a power converter (3) designed to generate a high-frequency power signal for powering a plasma or gas laser process and connectable to a load (6) for this purpose, wherein the power converter (3) comprises at least one amplifier stage (40) comprising: - a first amplifier path (42) comprising a first amplifier unit (42a), - a second amplifier path (43) comprising a second amplifier unit (43a), wherein the first amplifier path (42) is configured to output a first amplifier path output signal and the second amplifier path (43) is configured to output a second amplifier path output signal having a phase shift relative to the first amplifier path output signal, which is not equal to, in particular greater than, 0° and not equal to, in particular less than, 180°, wherein the amplifier paths (42, 43) are connected to a phase-shifting coupler unit (47) designed to convert the output signals of the amplifier paths (42, 43) to couple to a high-frequency power signal, wherein the first and second amplifier units (42a, 43a) each comprise the following components: i. a base-load amplifier (103) configured to provide base-load amplifier power; ii. a peak-load amplifier (104) configured to provide peak-load amplifier power; and iii. a power coupler (107) for combining the base load amplifier power and the peak load amplifier power at the output of the respective first and second amplifier units (42a, 43a) to a power amplifier output power (P _out ) wherein the power supply system (2) is configured to generate a power boost above the rated power of the power supply system (2), in particular for igniting a plasma or gas laser, wherein an amplitude and/or phase relationship between the base load amplifier (103) and the peak load amplifier (104) of at least one of the first and second amplifier units (42a, 43a) is adjustable, in particular briefly, such that the amplifier output power (P _out ) of the amplifier unit (42a, 43a) is greater than a rated power of the amplifier unit (42a, 43a). Plasma system (1), comprising a. a power supply system (2) according to Claim 14 , b. a load (6), in particular configured as a plasma or gas laser process, • wherein the power supply system (2) has a power converter (3) which can be connected to a voltage supply network (4) • wherein the power converter (3) is connected to the load (6) is connected, • wherein in particular an impedance matching network (5) is arranged between the load (6) and the power converter (3).