KR20190114920A - Plasma pulse power supply - Google Patents

Abstract

A plasma pulse power supply according to one embodiment of the present invention comprises: an AC/DC conversion circuit module converting an AC voltage into a DC voltage; a pulse voltage conversion module converting the DC voltage converted by the AC/DC conversion circuit module into a pulse voltage and providing the pulse voltage to the load; and a clamp circuit module charged with a clamp voltage larger than a magnitude of the DC voltage converted by the AC/DC conversion circuit module and providing the clamp voltage to the load during an initial boosting period of the pulse voltage. The pulse voltage conversion module may include a pulse switching module that the pulse switching module may be short-circuited during a turn-on period but the pulse switching module may provide the DC voltage converted by the AC/DC conversion circuit module to the load during a turn-off period.

Description

Plasma pulsed power supply unit {PLASMA PULSE POWER SUPPLY}

The present application relates to a plasma pulse power supply device.

The plasma power supply device is a power supply device for generating and maintaining a plasma called a fourth state of a material, and is used in, for example, a thin film manufacturing process for semiconductors and flat panel displays.

In such a plasma power supply device, a voltage in the form of a pulse is applied instead of a DC voltage, thereby reducing the frequency of generation of an arc causing a bad process.

1 illustrates a current waveform 20 by a pulse voltage 10 and an applied pulse voltage 10 provided to a load in a conventional plasma pulse power supply.

The load of the plasma thin film process has the same characteristics as the inductor. That is, even if the pulse voltage 10 is increased, the load current 20 has a characteristic of gradually increasing over time without immediately increasing.

Therefore, when the pulse voltage 10 of a high frequency of several tens of kHz is applied, the average power delivered to the load is lowered due to the increased delay of the current 20 as shown in FIG. 1.

In order to solve this problem, a method of increasing the magnitude of the pulse voltage may be considered to increase the average power delivered to the load. However, since the high discharge voltage causes insulation breakdown of the plasma discharge electrode and interferes with the normal process, the magnitude of the pulse voltage is increased. There is a limit to increase.

In addition, in order to generate a pulse voltage, the switch must be repeatedly turned on and off.However, at an initial moment of turning off the switch, high voltage is induced on the discharge electrode due to the high impedance of the load and high back electromotive force, so that the dielectric breakdown of the discharge electrode is switched as well. There is a problem of damaging the device.

As a technique related to a plasma power supply device, for example, Korean Patent Publication No. 2006-0094467 (“Arc Detection for Plasma Power Supply and Energy Reduction Circuit by Arc”, Publication Date: August 29, 2006). .

Korean Laid-Open Patent No. 2006-0094467 (“Arc Detection for Plasma Power Supply and Energy Reduction Circuit by Arc”, Publication Date: August 29, 2006)

According to one embodiment of the present invention, not only the breakdown of the discharge electrode but also the breakage of the switching element can be prevented, and at the same time, the current rise time can be shortened to increase the average power delivered to the load. do.

In addition, according to another embodiment of the present invention, there is provided a plasma pulse power supply device that can prevent the increase in the clamp voltage due to the current flowing into the clamp circuit module and increase the energy efficiency.

According to another embodiment of the present invention, the current sharing of the load due to the difference in output voltage of each plasma pulsed power supply device can be made uniform when the above-described plasma pulsed power supply devices are connected in parallel.

According to one embodiment of the present invention, an AC / DC conversion circuit module for converting an AC voltage into a DC voltage; A pulse voltage conversion module converting the DC voltage converted by the AC / DC conversion circuit module into a pulse voltage and providing the result to a load; And a clamp circuit module charged with a clamp voltage greater than the magnitude of the DC voltage converted by the AC / DC conversion circuit module, and providing the clamp voltage to the load during an initial boosting period of the pulse voltage. The pulse voltage conversion module is short-circuited during the turn-on period, but during the turn-off period, a pulse switching module for providing the DC voltage converted by the AC / DC conversion circuit module to the load is provided. .

According to another embodiment of the present invention, there is provided an AC / DC conversion circuit module; An inductor having one end connected to a first output terminal of the AC / DC conversion circuit module; A pulse switching module connected between the other end of the inductor and the second output end of the AC / DC conversion circuit module; A clamp diode having an anode connected to the other end of the inductor; A clamp capacitor having one end connected to a cathode of the clamp diode and the other end connected to a second output end of the AC / DC conversion circuit module; A clamp switch, one end of which is connected to the clamp capacitor; A cathode connected to the other end of the clamp switch, the other end of the freewheeling diode connected between a second output end of the AC / DC conversion circuit module; A discharge inductor having one end connected to a cathode of the freewheeling diode and the other end connected to one end of the inductor; And a reverse current prevention diode connected between one end of the pulse switching module and the load.

According to another embodiment of the present invention, a first pulse voltage conversion module for converting a DC voltage converted by the first AC / DC conversion circuit module and the first AC / DC conversion circuit module into a pulse voltage and providing the load to a load And a first clamp voltage charged to a first clamp voltage that is greater than a magnitude of the DC voltage converted by the first AC / DC conversion circuit module, and providing the first clamp voltage to the load during an initial boosting period of the pulse voltage. A first plasma pulse power supply having a clamp circuit module; And a second AC / DC conversion circuit module, a second pulse voltage conversion module converting a DC voltage converted by the second AC / DC conversion circuit module into a pulse voltage and providing the load to the load, and the second AC / DC conversion circuit. And a second clamp circuit module charged with a second clamp voltage larger than the magnitude of the DC voltage converted by the DC conversion circuit module, and providing the second clamp voltage to the load during the initial boosting period of the pulse voltage. And a second plasma pulse power supply connected in parallel with the first plasma pulse power supply, wherein each of the first plasma pulse power supply and the second plasma pulse power supply includes the first plasma pulse power supply during the initial boosting period of the pulse voltage. A plasma pulsed power supply is further provided, further comprising a droop circuit for compensating the voltage difference between the clamp voltage and the second clamp voltage.

According to one embodiment of the present invention, by absorbing the current flowing in the inductor in the initial boosting period of the pulse voltage by the clamp circuit, it is possible to prevent breakage of the switching electrode as well as breakdown of the discharge electrode. In addition, by providing a clamp voltage having a high magnitude to the load in the initial boosting period of the pulse voltage, it is possible to shorten the current rise time to increase the average power delivered to the load.

Further, according to another embodiment of the present invention, the clamp voltage due to the current flowing into the clamp circuit module by discharging (regenerating) the AC / DC conversion circuit module again in the initial boosting period of the pulse voltage. It can prevent the rise and increase the energy efficiency.

In addition, according to another embodiment of the present invention, by adding a droop circuit in parallel connection of the above-described plasma pulsed power supply device, it is possible to reduce the output voltage difference of each plasma pulsed power supply device, and also to be introduced into the first clamp circuit module. By controlling the amount of current and the amount of current flowing into the second clamp circuit module in the same manner, the current sharing of the load due to the voltage difference between the first clamp voltage and the second clamp voltage can be made uniform.

1 illustrates a current waveform by a pulse voltage and an applied pulse voltage provided to a load in a conventional plasma pulse power supply.
2 is a schematic diagram of a plasma pulse power supply according to an embodiment of the present invention.
3 illustrates a current waveform by a pulse voltage and an applied pulse voltage provided to a load in the plasma pulse power supply of FIG. 2 according to an embodiment of the present invention.
4 is a waveform diagram of an essential part of the plasma pulse power supply device of FIG. 2 according to an embodiment of the present invention.
5A illustrates a plasma pulse power module connected in parallel according to an embodiment of the present invention.
FIG. 5B is a diagram illustrating a control module for controlling the plasma pulse power module shown in FIG. 5A.
6A to 6B are comparison waveform diagrams for the main part of the plasma pulse power supply device of FIGS. 5A to 5B according to one embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, embodiments of the present invention may be modified in various other forms, and the scope of the present invention is not limited to the embodiments described below. Shapes and sizes of the elements in the drawings may be exaggerated for clarity, elements denoted by the same reference numerals in the drawings are the same elements.

2 is a schematic diagram of a plasma pulse power supply 200 according to an embodiment of the present invention.

First, as shown in FIG. 2, the plasma pulse power supply 200 according to the embodiment of the present invention includes an AC / DC conversion circuit module 211, pulse voltage conversion modules LF1 and PWM_SW1, and a clamp circuit module. 212 and 213 (hereinafter, referred to as a plasma power supply module 210) and a control module 220.

The above-described pulse voltage conversion modules LF1 and PWM_SW1 are composed of an inductor LF1 and a pulse switching module PWM_SW1. The clamp circuit module 212, 213 is a clamp circuit 212 consisting of a clamp diode (D1_CMP) and a clamp capacitor (C1_CMP), and a discharge consisting of a clamp switch (CMP_SW1), a clamp inductor (L1_CMP) and a freewheeling diode (D1_FW). It consists of a circuit 213. Meanwhile, reference numeral D1_R shown in FIG. 2 is a reverse current prevention diode.

Specifically, the AC / DC conversion circuit module 211 is a module that converts an AC voltage into a DC voltage. The AC / DC conversion circuit module 211 may include, for example, a boosted multi-level PWM chopper or a multi-level Vienna PWM rectifier, but is not limited thereto.

The pulse voltage conversion modules LF1 and PWM_SW1 may convert the DC voltage converted by the AC / DC conversion circuit module 211 into a pulse voltage and provide it to the load.

Specifically, the pulse voltage conversion modules LF1 and PWM_SW1 are short-circuited during the turn-on period of the inductor LF1 and the pulse switching module PWM_SW1 that operate as a current source, but are converted to AC / DC during the turn-off period of the pulse switching module PWM_SW1. It may include a pulse switching module (PWM_SW1) for providing a direct current voltage converted by the circuit module 211 to the load.

The above-mentioned pulse switching module PWM_SW1 may be configured as a single switching device to provide a unidirectional pulse voltage, or four switching devices may be configured as an H bridge type to provide a bidirectional pulse voltage. The switching frequency and duty of the above-mentioned pulse switching module PWM_SW1 are determined at a request of a customer, and may be, for example, several tens of kHz. However, the present invention is not limited to the above-described specific numerical values.

Meanwhile, the above-described load may have an inductor characteristic applied to the plasma thin film process. Thus, when a pulse voltage is applied, the current has a pattern that increases with time.

The clamp circuit module 212 is charged with a clamp voltage V1_CMP greater than the magnitude of the DC voltage converted by the AC / DC conversion circuit module 211, and may provide the clamp voltage to the load during the initial boosting period of the pulse voltage. have.

The magnitude of the clamp voltage V1_CMP may be determined in consideration of the current rise time (see T1 'in FIG. 3), for example, approximately 150% of the magnitude of the DC voltage converted by the AC / DC conversion circuit module 211. It can have a value between 200% and 200%. The value is designed in consideration of the breakdown voltage, the load, etc. of the pulse switching module PWM_SW1 having the magnitude of the clamp voltage V1_CMP described above. It is not limited to numerical value.

The initial boosting period of the pulse voltage may be a period from a turn-off time of the pulse switching module PWM_SW1 to a time point at which the current flowing in the inductor LF1 and the current flowing in the load are the same.

Specifically, the clamp circuit modules 212 and 213 may include a clamp circuit 212 composed of a clamp capacitor C1_CMP connected in series with the clamp diode C1_CMP and the clamp diode C1_CMP, and charged with the clamp voltage V1_CMP. It may include a discharge circuit 213 for maintaining a constant magnitude of the clamp voltage (V1_CMP) by discharging the current flowing into the clamp circuit 212 to the AC / DC conversion circuit module 211 during the initial boosting period.

On the other hand, the above-described discharge circuit 213 is a discharge inductor (L1_CMP) to discharge the energy stored in the clamp capacitor (C1_CMP1) to the AC / DC conversion circuit module 211 when the clamp switch (CMP_SW1), clamp switch (CMP_SW1) is turned on. When the clamp switch CMP_SW1 is turned off, the clamp switch CMP_SW1 may include a freewheeling diode D1_FW for freewheeling energy stored in the discharge inductor L1_CMP.

Specifically, the above-described plasma pulse power supply 200 has a structure as shown in FIG. 2, that is, an AC / DC conversion circuit module 211 and one end thereof at a first output terminal of the AC / DC conversion circuit module 211. A clamp diode connected between the connected inductor LF1, the other end of the inductor LF1 and the second output end of the AC / DC conversion circuit module 211, and a clamp diode whose anode is connected to the other end of the inductor LF1. (D1_CMP), one end is connected to the cathode of the clamp diode (D1_CMP), the other end is a clamp capacitor (C1_CMP) connected to the second output terminal of the AC / DC conversion circuit module 211, and one end is connected to the clamp capacitor (C1_CMP) The connected clamp switch CMP_SW1, the cathode is connected to the other end of the clamp switch CMP_SW1, the other end is a freewheeling diode D1_DW connected between the second output terminal of the AC / DC conversion circuit module 211, one end is free Is connected to the cathode of the wheeling diode (D1_DW) and the other end is A discharge inductor L1_CMP connected to one end of the ductor LF1 and a reverse current prevention diode D1_R connected between one end of the pulse switching element PWM_SW1 and a load.

Meanwhile, FIG. 3 illustrates a current waveform by a pulse voltage and an applied pulse voltage provided to a load in the plasma pulse power supply 200 of FIG. 2 according to an embodiment of the present invention.

Compared with the waveform of FIG. 1, according to the plasma pulse power supply of FIG. 2 according to an embodiment of the present invention, the magnitude of the voltage Vo provided to the load during the initial boosting period 301 of the pulse voltage Vo is It is applied with a magnitude higher than the pulse voltage 10 of FIG. It can be seen that the desired current value is reached at a quick time (T1-> T1 ').

3 is a section in which a DC voltage converted by the first AC / DC conversion circuit module 211 is provided to the load. For convenience, the initial boosting section 301 is referred to as a 'current control section' and the remaining section 302 is referred to as a 'voltage control section'.

4 is a waveform diagram of an essential part of the plasma pulse power supply of FIG. 2 according to an embodiment of the present invention, (a) denotes an output voltage Vo and a clamp voltage V1_CMP, and (b) denotes a load current I (P1). )) And the inductor current (I (LF1)), (c) is the current flowing into the clamp diode (C1_CMP), (d) is the discharge current discharged through the discharge inductor (L1_CMP), (e) is the pulse switching module The pulse switching signal S_PWM_SW1 of (PWM_SW1) is shown. Toff is a turn-off period of the pulse switching module PWM_SW1, Ton is a turn-on period of the pulse switch module PWM_SW1, 301 is an initial boosting period (current control period), and 302 is a voltage control period.

Hereinafter, an operation of the plasma power generator 200 according to an embodiment of the present invention will be described in detail with reference to FIGS. 2 to 4.

First, when the pulse switching module PWM_SW1 is turned on, the pulse switching module PWM_SW1 is shorted in the turn-on period Ton, so that the current I (LF1) flowing through the inductor LF1 passes through the pulse switching module PWM_SW1. The voltage (Vo) which flows and thus provides the load becomes OV.

Thereafter, when the pulse switching module PWM_SW1 is turned off, the current I (P1) flowing to the load gradually rises (see FIG. 4B), and thus the initial boosting period 301 (ie, pulse). The current I flowing through the inductor LF1 from the turn-off time of the switching module PWM_SW1 to the time when the current I (LF1) flowing through the inductor LF1 and the current I (P1) flowing through the load are the same). The current difference between LF1) and the current I (P1) flowing through the load flows through the clamp capacitor CMP_SW1, and the voltage V1_CMP charged in the clamp capacitor C1_CMP is provided to the load.

After that, when the current I (LF1) flowing in the inductor LF1 and the current I (P1) flowing in the load are the same, all of the current I (LF1) flowing in the inductor LF1 flows to the load. In this case, the load is provided with a DC voltage converted by the AC / DC conversion circuit module 211.

On the other hand, the control module 220 according to an embodiment of the present invention can maintain the magnitude of the clamp voltage V1_CMP by controlling the clamp switch CMP_SW1 of the discharge circuit 213. The switching frequency of the clamp switch CMP_SW1 described above may be designed to be smaller than the switching frequency of the pulse switching module PWM_SW1.

In detail, the control module 220 may include an error calculator 221, a PI controller 222, and a PWM generator 223, and the error calculator 221 may include a clamped clamp voltage V1_CMP and a clamp voltage command value ( The voltage error between V1_CMP ^* ) is calculated and transmitted to the PI controller 221.

The PI controller 221 may generate a voltage reference value according to the voltage error transmitted from the error calculator 221 and transmit the generated voltage reference value to the PWM generator 223. Meanwhile, the PWM generator 223 generates a switching signal S_CMP_SW1 of the clamp switch CMP_SW1 by comparing the voltage reference value with a reference wave such as a triangular wave, for example, and the clamp switch CMP_SW1 is controlled by the generated switching signal S_CMP_SW1. As a result, the magnitude of the clamp voltage V1_CMP may be kept constant.

Meanwhile, in the case of the discharge circuit 213, when the clamp switch CMP_SW1 is turned on, the energy stored in the clamp switch CMP_SW1 (specifically, the voltage V1_CMP charged in the clamp switch CMP_SW1) and the AC / DC conversion circuit module ( Energy as much as the voltage difference between the DC voltages converted by 211) may be discharged (regenerated) to the AC / DC conversion circuit module 211 through the discharge inductor L1_CMP. Thereafter, when the clamp switch CMP_SW1 is turned off, energy stored in the discharge inductor L1_CMP may be freewheeled through the freewheeling diode D1_FW.

As described above, according to an embodiment of the present invention, by absorbing the current flowing through the inductor in the initial boosting period of the pulse voltage in the clamp circuit, it is possible to prevent breakage of the discharge electrode and damage of the switching element. In addition, by providing a clamp voltage having a high magnitude to the load in the initial boosting period of the pulse voltage, it is possible to shorten the current rise time to increase the average power delivered to the load.

Further, according to another embodiment of the present invention, the clamp voltage due to the current flowing into the clamp circuit module by discharging (regenerating) the AC / DC conversion circuit module again in the initial boosting period of the pulse voltage. It can prevent the rise and increase the energy efficiency.

5A is a diagram illustrating a plasma pulsed power supply module 500 connected in parallel according to one embodiment of the present invention, and FIG. 5B is a control for controlling the plasma pulsed power supply module 500 shown in FIG. 5A. Figure shows a module.

The plasma pulsed power supply module 500 shown in FIG. 5A is a parallel connection of two plasma power supply modules 510 and 520 as shown in FIG. 2 having the same rating, and the internal elements of the two plasma power supply modules 510 and 520 are connected. The values are designed identically, and the first pulse switching module PWM_SW1 and the second pulse switching module PWM_SW2 may be controlled by the same pulse switching signal.

In order to distinguish the two plasma power modules 510 and 520, reference numeral 510 is referred to as a first plasma power module, and reference numeral 520 may be referred to as a second plasma power module, and thus internal components may be referred to. have. For example, if reference numeral 511 is a first AC / DC conversion circuit module, reference numeral 521 is a second AC / DC conversion circuit module. If reference numeral LF1 is a first inductor, reference numeral LF2 is the same as that of the second inductor. It may be referred to as.

On the other hand, it is different from FIG. 2, the difference between the clamp voltage (V1_CMP, V2_CMP) charged in the first and second clamp capacitor (C1_CMP, C2_CMP) in each of the two plasma power supply modules (510, 520) in parallel operation Droop circuits 514 and 524 are further included to compensate for the difference, and control for uniforming the current sharing of the load by the voltage difference between the first clamp voltage V1_CMP and the second clamp voltage V2_CMP during parallel operation. The operation of the module 530 is different from the operation of the control module 220 of FIG. 2.

Specifically, as shown in FIGS. 5A and 5B, the plasma pulsed power supply 500 connected in parallel according to an embodiment of the present invention may include a first plasma pulsed power supply module 510 and a second plasma pulsed power supply module 520. ) And a control module 530 for controlling them, the control module 530 may be composed of a first control module 540 and a second control module 550.

Specifically, the first plasma pulse power module 510 converts the DC voltage converted by the first AC / DC conversion circuit module 511 and the first AC / DC conversion circuit module 511 into a pulse voltage to load The first pulse voltage conversion module LF1 and PWM_SW1 and the first clamp voltage greater than the magnitude of the DC voltage converted by the first AC / DC conversion circuit module LF1 and PWM_SW1 are supplied to the pulse voltage conversion module LF1 and PWM_SW1. During the initial boosting period, first clamp circuit modules 512 and 513 may be provided to provide the first clamp voltage V1_CMP to the load.

The first clamp circuit modules 512 and 513 described above are connected to the first clamp diode C1_CMP and the first clamp diode C1_CMP in series to be the first clamp capacitor C1_CMP charged with the first clamp voltage V1_CMP. A first clamp circuit 512 configured and a first discharge circuit 513 for discharging current flowing into the first clamp circuit 212 to the first AC / DC conversion circuit module 511 during the initial boosting period. Can be.

On the other hand, the first discharge circuit 513 described above, when the first clamp switch CMP_SW1 and the first clamp switch CMP_SW1 are turned on, the first discharge circuit 513 converts the energy stored in the first clamp capacitor C1_CMP1 into the first AC / DC conversion circuit module ( And a first freewheeling diode D1_FW for freewheeling energy stored in the first discharge inductor L1_CMP when the first discharge inductor L1_CMP for discharging the battery 511 is turned off and the first clamp switch CMP_SW1 is turned off. can do.

In addition, the second plasma pulse power module 520 converts the DC voltage converted by the second AC / DC conversion circuit module 521 and the second AC / DC conversion circuit module 521 into a pulse voltage to load the load. The second pulse voltage conversion module LF2 and PWM_SW2 and the second clamp voltage greater than the magnitude of the DC voltage converted by the second AC / DC conversion circuit module LF2 and PWM_SW2 are charged. During the boosting period, second clamp circuit modules 522 and 523 may be provided to provide the second clamp voltage V2_CMP to the load.

The second clamp circuit module 522 and 523 described above are connected to the second clamp diode C2_CMP and the second clamp diode C2_CMP in series to be the second clamp capacitor C2_CMP charged with the second clamp voltage V2_CMP. A second clamp circuit 522 configured and a second discharge circuit 523 for discharging current flowing into the second clamp circuit 522 to the second AC / DC conversion circuit module 521 during the initial boosting period. Can be.

On the other hand, the second discharge circuit 523 described above, when the second clamp switch CMP_SW1 and the second clamp switch CMP_SW1 are turned on, the second discharge circuit 523 converts energy stored in the second clamp capacitor C1_CMP1 into a second AC / DC conversion circuit module ( And a second freewheeling diode D2_FW for freewheeling the energy stored in the second discharge inductor L2_CMP when the second discharge inductor L2_CMP for discharging to the second discharge switch LMP_SW2 is turned off. can do.

The first plasma pulse power module 510 and the second plasma pulse power module 520 described above may be connected in parallel. That is, the first output terminal of the first plasma pulse power module 510 is connected to the first output terminal of the second plasma pulse power module 520, and the second output terminal of the first plasma pulse power module 510 is the second plasma. Each of the pulse power modules 520 may be connected to the second output terminal.

The first plasma pulse power module 510 and the second plasma pulse power module 520 are connected in parallel, and the clamp voltage V1_CMP of the first plasma pulse power module 510 and the second plasma pulse power module 520 are When the clamp voltages V2_CMP are independently controlled to follow the same clamp voltage command value, voltage deviations may occur between the clamp voltages of the respective modules 510 and 520. The voltage deviation may be due to various causes such as sensor error and control error of each plasma power supply module 510 and 520.

Due to the voltage deviation between the clamp voltages, the current control section, which is the initial boosting section, supplies current to the load only in the plasma power module having a relatively high clamp voltage, and cannot supply current to the load in the plasma power module having the lower clamp voltage. .

That is, in the case of a module having a relatively low clamp voltage among the first plasma pulse power module 510 and the second plasma pulse power module 520, the inductor current does not flow to the load and flows to the clamp circuit, and the clamp voltage is relatively high. In the case of the module, the inductor current flows directly to the load. This causes non-uniform load current sharing of each module 510, 520, which may cause problems in the durability of each module 510, 520, and may cause hunting of current, thereby causing problems in reliability of the plasma power supply. Can cause.

Accordingly, according to one embodiment of the present invention, the first plasma pulse power module 510 and the second plasma pulse power module 520 described above are respectively the first clamp voltage V1_CMP and the first clamp voltage during the initial boosting period of the pulse voltage. It may further include droop circuits 514 and 524 for compensating the voltage difference between the two clamp voltages V2_CMP.

The droop circuits 514 and 524 described above may include a resistor and a capacitor connected in parallel, or as a single resistor as shown in FIG. 5A.

Specifically, according to the droop circuits 514 and 524 according to one embodiment of the present invention, when a large amount of current flows into the clamp circuit of the plasma power supply module having a low clamp voltage, the droop voltage across the droop circuit is increased. Accordingly, since the droop voltage + clamp voltage is provided to the load in the initial boost period, the voltage difference between the clamp voltages V1_CMP and V2_CMP of the first plasma pulse power module 510 and the second plasma pulse power module 520 may cause a droop circuit. Through compensation, the current sharing of the load due to the voltage difference between the first clamp voltage and the second clamp voltage can be made uniform.

On the other hand, according to another embodiment of the present invention, the control module 530 controls the amount of current flowing into the first clamp circuit module 512 and the amount of current flowing into the second clamp circuit module 522 to thereby equal the first Even when there is a voltage difference between the clamp voltage V1_CMP and the second clamp voltage V2_CMP, the current sharing of the load can be made uniform.

Specifically, during the initial boosting period, the load current I (P1) = the current I (LF1) of the first inductor LF1-the first clamp current I (D1_CMP), and the load current I (P2). = Current I (LF2) of the second inductor LF2-the second clamp current I (D1_CMP).

That is, if it is assumed that the current I (LF1) of the first inductor and the current I (LF2) of the second inductor are the same, the first clamp current I (the current flowing into the first clamp circuit 512) When the amount of current of D1_CMP and the amount of current of the second clamp current I (D2_CMP), which is the current flowing into the second clamp circuit 522, are controlled to be the same, the clamp voltages V1_CMP and V2_CMP of the respective plasma power supply modules 510 and 520 are controlled. It can be seen that the current amount of the load current I (P1) and the current amount of the load current I (P2) can be controlled to be equal even when a voltage deviation occurs between the?

In other words, an amount of current of the first clamp current I (D1_CMP), which is a current flowing into the first clamp circuit 512, is averaged from the first clamp circuit 512 to the first AC / DC conversion circuit module 511. The amount of current of the second clamp current I (D2_CMP), which is a current flowing into the second clamp circuit 522, is equal to the amount of current discharged, and the second AC / DC conversion circuit module is averaged from the second clamp circuit 522. It is equal to the amount of current discharged at 521.

Therefore, the amount of current discharged from the first clamp circuit 512 to the first AC / DC conversion circuit module 511 and the second clamp circuit 522 by controlling the first clamp switch CMP_SW1 and the second clamp switch CMP_SW2. When the amount of current discharged to the second AC / DC conversion circuit module 521 is equal, the amount of current of the load current I (P1) and the amount of current of the load current I (P2) are not changed despite the voltage deviation of the clamp voltage. The same can be controlled.

To this end, the above-described control module 530 controls the first clamp switch CMP_SW1 of the first plasma power module 510 and the second clamp switch of the second plasma power module 520. It may include a second control module 550 to control (CMP_SW2). The first control module 540 may be referred to as a 'master control module' and the second control module 550 may be referred to as a 'slave control module'.

In detail, the master control module 540 generates a current command value I (L1_CMP) ^* from the first clamp voltage V1_CMP and the clamp voltage command value V_CMP ^* charged in the first clamp circuit module 512. First clamp switching signal for switching the first clamp switch CMP_SW1 from the generated current command value I (L1_CMP) ^* and the first clamp current I (L1_CMP) emitted from the first clamp circuit module 512. (S_CMP_SW1) can be generated.

To this end, the master control module 540, as shown in Figure 5b, to the error calculator 541, hysteresis controller 542, PI controller 543, current control module 544 and PWM generator 545 The current control module 544 may be configured with an error calculator 544a and a PI controller 544b.

Referring to the operation of the above-described master control module 540, the voltage error between the first clamp voltage (V1_CMP) and the clamp voltage command value (V1_CMP ^* ) fed back by the error calculator 541 is calculated, the calculated voltage error Transfer to hysteresis controller 542.

The hysteresis controller 542 is also referred to as a dead-band controller, and transmits the voltage error to the PI controller 543 when the voltage error transmitted from the error calculator 541 is outside the preset band range. When the voltage error transmitted from the calculator 541 is within a preset band range, a voltage error of "0" is transmitted to the PI controller 543.

That is, the hysteresis controller 542 performs the PI control only when the voltage error is out of the preset band range. In the case of the master control module 540, the preset band range may be "0" (ie, without the hysteresis controller 542). Since the PI controller 543 may deliver a current command value (I (L1_CMP ^*)), the generated current command value (I (L1_CMP ^*)) and generating a voltage according to the transmission error in the current control module 544.

The error calculator 544a of the current control module 544 calculates a current error between the current command value I (L1_CMP ^* ) transmitted from the PI controller 543 and the feedback discharge current I (L1_CMP). The current error can be passed to the PI controller 544b.

Meanwhile, the PI controller 544b may generate a current reference value according to the current error transmitted from the error calculator 544a and transmit the current reference value to the PWM generator 545.

Thereafter, the PWM generator 545 generates a switching signal S_CMP_SW1 of the first clamp switch CMP_SW1 by comparing the current reference value with a reference wave such as a triangular wave, and generates the first clamp switch (S_CMP_SW1) by the generated switching signal S_CMP_SW1. CMP_SW1) may be controlled.

Meanwhile, when the voltage difference between the second clamp voltage V2_CMP and the clamp voltage command value V_CMP ^* charged in the second clamp circuit module 522 is less than a predetermined value, the slave control module 550 may be a master control module 540. The second clamp switching signal for switching the second clamp switch (CMP_SW2) from the current command value (I (L1_CMP) ^*) and the discharge current (I (L2_CMP)) discharged to the second clamp circuit module 522 generated in S_CMP_DW2) may be generated.

That is, when the voltage difference between the second clamp voltage V2_CMP and the clamp voltage command value V_CMP ^* is less than a predetermined value, the slave control module 550 based on the current command value I_L1_CMP ^* generated by the master control module 540. The second clamp switching signal S_CMP_DW2 is generated.

On the other hand, when the voltage difference between the second clamp voltage V2_CMP charged in the second clamp circuit module 522 and the clamp voltage command value V_CMP ^* is greater than or equal to a predetermined value, the slave control module 550 may perform a second clamp circuit. The current command value is generated from the second clamp voltage V2_CMP and the clamp voltage command value V_CMP ^* charged in the module 522, and the generated current command value and the second clamp current input to the second clamp circuit module 522 ( The second clamp switching signal S_CMP_DW2 for switching the second clamp switch CMP_SW2 may be generated from I (D2_CMP).

To this end, the slave control module 550, as shown in Figure 5b, the error calculator 551, hysteresis controller 552, PI controller 553, the current control module 554, PWM generator 555 and The error calculator 556 may be configured, and the current control module 554 may include the error calculator 554a and the PI controller 554b.

Referring to the operation of the slave control module 550 described above, the voltage error between the second clamp voltage (V2_CMP) and the clamp voltage command value (V_CMP ^* ) fed back by the error calculator 551 is calculated, the calculated voltage error Transfer to hysteresis controller 552.

The hysteresis controller 552 is also referred to as a dead-band controller, and transmits the voltage error to the PI controller 543 when the voltage error transmitted from the error calculator 551 is outside the preset band range. When the voltage error transmitted from the calculator 551 is within a preset band range, a voltage error of "0" is transmitted to the PI controller 553. That is, the hysteresis controller 552 performs the PI control only when the voltage error is out of a preset range.

Thereafter, the PI controller 553 may generate a current command value according to the transmitted voltage error, and the generated current command value may be transmitted to the error calculator 556.

Error calculator 556 calculates an instruction value error (I (L2_CMP) ^*) between the current command value (I (L1_CMP) ^*) delivered from the current command value to the master control module 540 received from the PI controller 553, and operation The setpoint error I (L2_CMP) ^* may be transmitted to the current control module 554.

That is, when the voltage error transmitted from the error calculator 551 is within a preset band range, only the current command value I (L1_CMP) ^* in the master control module 540 is from the error calculator 556 to the current control module 554. Is delivered to. On the other hand, when the voltage error transmitted from the error calculator 551 is out of the preset band range, the current command value I (L1_CMP) ^* transmitted from the master control module 540 and the current command value generated by the PI controller 553 are different. The setpoint error may be passed to the current control module 554.

Meanwhile, the error calculator 554a of the current control module 554 calculates a current error between the command value error I (L2_CMP) ^* transmitted from the error calculator 556 and the feedback second discharge current I (L2_CMP). In addition, the calculated current error may be transmitted to the PI controller 554b.

Meanwhile, the PI controller 544b may generate a current reference value according to the current error transmitted from the error calculator 554a and transmit the current reference value to the PWM generator 555.

Finally, the PWM generator 555 generates a switching signal S_CMP_SW2 of the second clamp switch CMP_SW2 by comparing the current reference value with a reference wave such as a triangular wave, for example, and generates a switching signal of the generated second clamp switch CMP_SW2. The second clamp switch CMP_SW2 may be controlled by S_CMP_SW2.

Finally, FIGS. 6A to 6B are comparative waveform diagrams of main parts of the plasma pulsed power supply apparatus of FIGS. 5A to 5B according to one embodiment of the present invention, and FIG. 6A to FIGS. 5A to 6 according to one embodiment of the present invention. 5B is a waveform diagram of a main part of the plasma pulse power supply device, and the main part waveform when the control module 220 of FIG. 2 is provided in each of the plasma power supply modules 510 and 520 shown in FIG. 5A to control only the clamp voltage, respectively. It is also.

In FIG. 6A, (a) is an output voltage Vo, (b) is a first load current I (P1) and a second load current I (P2), and (c) is a first clamp current I ( D1_CMP and the second clamp currents I (D2_CMP) and (d) are second flows through the first discharge current I (L1_CMP) flowing through the first discharge inductor L1_CMP and the second discharge inductor L2_CMP. Discharge current I (L2_CMP), current command value I (L1_CMP) ^* , (e) are the first clamp voltage (V1_CMP) and the second clamp voltage (V2_CMP), and (f) are the droop circuits (514, 524). The first droop voltage V1_DR and the second droop voltage V2_DR, which are voltages between both ends, are referred to.

As shown in FIG. 6A, in the case of the plasma pulse power supply of FIGS. 5A to 5B according to an embodiment of the present invention, when a voltage deviation occurs between the first clamp voltage V1_CMP and the second clamp voltage V2_CMP ( Also in FIG. 6E, it can be seen that the first load current I (P1) and the second load current I (P2) are substantially the same, so that the load current is well shared.

Similarly, in FIG. 6B, (a) is the output voltage Vo, (b) is the first load current I (P1) and the second load current I (P2), and (c) is the first clamp current. (I (D1_CMP)) and the second clamp current (I (D2_CMP)) and (d) are the first discharge current I (L1_CMP) and the second discharge inductor L2_CMP flowing through the first discharge inductor L1_CMP. The second discharge current I (L2_CMP) and (e) flowing through) denote the first clamp voltage V1_CMP and the second clamp voltage V2_CMP.

Unlike in FIG. 6A, in the case of FIG. 6B, the control module 220 of FIG. 2 is provided in each of the plasma power modules 510 and 520 shown in FIG. 5A to control only the clamp voltage. It can be seen that a voltage deviation occurs (see (e) of FIG. 6B), thereby causing an unbalance of the load current between the first load current I (P1) and the second load current I (P2) ( (B) of FIG. 6B).

As described above, according to another embodiment of the present invention, by adding a droop circuit in parallel connection of the above-described plasma pulsed power supply device, it is possible to reduce the output voltage difference of each plasma pulsed power supply device, and further, the first clamp circuit module. By controlling the amount of current flowing into and the amount of current flowing into the second clamp circuit module in the same manner, the current sharing of the load due to the voltage difference between the first clamp voltage and the second clamp voltage can be made uniform.

The present invention is not limited by the above-described embodiment and the accompanying drawings. It is intended to limit the scope of the claims by the appended claims, and that various forms of substitution, modification and change can be made without departing from the spirit of the present invention as set forth in the claims to those skilled in the art. Will be self explanatory.

200: plasma pulse power supply
210, 510, 520: plasma pulse power module
211, 511, 521: AC / DC conversion circuit module
212, 512, 522: clamp circuit module
213, 513, 523: discharge circuit
514, 524: droop circuit
220, 530: control module
221, 541, 551, 544a, 554a, 556: error calculator
222, 543, 544b, 553, 554b: PI controller
542, 552: hysteresis controller
223, 545, 555: PWM generator
544, 545: current control module
301: current control section
302: voltage control section
303, 304: load current

Claims (9)

An AC / DC conversion circuit module for converting an AC voltage into a DC voltage;
A pulse voltage conversion module converting the DC voltage converted by the AC / DC conversion circuit module into a pulse voltage and providing the result to a load; And
And a clamp circuit module charged with a clamp voltage larger than the magnitude of the DC voltage converted by the AC / DC conversion circuit module, and providing the clamp voltage to the load during an initial boosting period of the pulse voltage.
The pulse voltage conversion module may include a pulse switching module that is short-circuited during a turn-on period but provides a DC voltage converted by the AC / DC conversion circuit module to the load during a turn-off period. The method of claim 1,
The clamp circuit module,
Clamp diodes; And
A clamp capacitor connected in series with the clamp diode to charge the clamp voltage;
Including, plasma pulse power supply. The method of claim 2,
The clamp circuit module,
A discharge circuit for maintaining a constant magnitude of the clamp voltage by discharging the current flowing into the clamp circuit module during the initial boosting period to the AC / DC conversion circuit module;
Further comprising a plasma pulse power supply. The method of claim 3,
The discharge circuit,
Clamp switch;
A discharge inductor for discharging energy stored in the clamp capacitor to the AC / DC conversion circuit module when the clamp switch is turned on; And
A freewheeling diode which freewheels the energy stored in the discharge inductor when the clamp switch is turned off;
Including, plasma pulse power supply. The method of claim 1,
The pulse voltage conversion module,
It may further include an inductor for current control,
The initial boosting period of the pulse voltage is a period from the turn-off time of the pulse switching module to the time when the current flowing in the inductor and the current flowing in the load is the same, plasma pulse power supply. The method of claim 1,
The load,
A plasma pulse power supply having an inductor characteristic applied to a plasma thin film process. The method of claim 5,
The pulse switching module,
A plasma pulse power supply, comprising a single switching element to provide a unidirectional pulse voltage or four switching elements configured to an H bridge type to provide a bidirectional pulse voltage. The method of claim 1,
The AC / DC conversion circuit module,
A plasma pulsed power supply comprising a boosted multi-level PWM chopper or a multi-level Vienna PWM rectifier. AC / DC conversion circuit module;
An inductor having one end connected to a first output terminal of the AC / DC conversion circuit module;
A pulse switching module connected between the other end of the inductor and the second output end of the AC / DC conversion circuit module;
A clamp diode having an anode connected to the other end of the inductor;
A clamp capacitor having one end connected to a cathode of the clamp diode and the other end connected to a second output end of the AC / DC conversion circuit module;
A clamp switch, one end of which is connected to the clamp capacitor;
A cathode connected to the other end of the clamp switch, the other end of the freewheeling diode connected between a second output end of the AC / DC conversion circuit module;
A discharge inductor having one end connected to a cathode of the freewheeling diode and the other end connected to one end of the inductor; And
A reverse current prevention diode connected between one end of the pulse switching module and a load;
Including, plasma pulse power supply.

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