JP2005286936A - Output power control method for high frequency power supply and high frequency power supply device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem in which electric discharge may be extinguished in a while from start of electric discharge to matching and it adversely affects a work process of an etching device and a CVD device which use electric discharge, when connected load is discharge load in a conventional high frequency power supply device. <P>SOLUTION: When a voltage detection value of a load side is higher than a voltage setting value compared to a matching part of a matching circuit, a power detection value is controlled to become equal to a power setting value. When the voltage detection value of the load side is under the voltage setting value compared to the matching part of the matching circuit, the power detection value is controlled to be equal to a value obtained by adding a command value for increasing output of high frequency power to the power setting value. The voltage detection value of the load side is controlled so that it does not become smaller than the voltage setting value compared to the matching part of the matching circuit. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a high-frequency power supply apparatus that supplies power to a load such as a plasma processing apparatus that performs plasma etching and plasma CVD, for example, via a matching unit.

  As a high-frequency power supply device that supplies high-frequency power to a load via a matching unit, conventionally, a traveling wave power output from the high-frequency power supply device or a method of constantly controlling load-side power obtained by subtracting reflected wave power from traveling wave power is used. Has been.

FIG. 5 is a block diagram showing the configuration of the conventional high-frequency power supply device 1p, the configuration of the matching device 3p, and the connection relationship between the high-frequency power supply device 1p, the matching device 3p, and the load 5.
The conventional high frequency power supply device 1p is a power supply device for supplying high frequency power to the load 5 through the transmission line 2, the matching unit 3p, and the load connection unit 4, and amplifies the high frequency signal output from the oscillation unit 11 Amplified at 12 and outputs high-frequency power via the power detector 13. The high frequency power output from the amplifying unit 12 of the high frequency power supply device 1p and directed to the load 5 is referred to as traveling wave power.
The traveling wave power PF and the reflected wave power PR detected by the power detection unit 13 are fed back to the power control unit 16p, and the traveling wave power PF or the load side power (traveling wave power−reflected wave power) is output power setting unit. 15 is controlled by the power control unit 16p so that the output power set value set at 15 is the same.

  The transmission line 2 is a line for transmitting power, and for example, a coaxial cable, a waveguide, a coaxial tube, or the like is used. The load connection portion 4 is made of, for example, a copper plate shielded so that electromagnetic waves do not leak, and the matching unit 3p and the load 5 are connected via the load connection portion 4.

  The matching unit 3p has a power source side impedance Zo (usually 50Ω in many cases) viewed from the input end of the matching unit 3p via the transmission line 2 and a load from the input end of the matching unit 3p. This is a device used for the purpose of impedance matching between the high frequency power supply device 1p and the load 5 by matching the load side impedance ZL (impedance of the matching device 3p and the load connection unit 4 and the load 5) as viewed from the side. is there.

The matching unit 3p is mainly composed of a matching unit 32 and a matching unit control unit 31.
The matching unit 32 is configured by a variable impedance element (for example, a variable capacitor, a variable inductor, etc.) and a fixed impedance element (for example, a fixed capacitor, a fixed inductor, etc.), and by changing the impedance of the variable impedance element, the high frequency power supply device 1p And the load 5 can be impedance-matched. In this example, the matching unit 32 is configured by the variable capacitors C1 and C2 and the fixed inductor L1.
The matching unit controller 31 includes a high-frequency power detector (not shown), detects a voltage component, a current component, and a phase difference between the voltage component and the current component of the high-frequency power, and the high-frequency power supply device 1p and the load based on the detected information 5 has a function of controlling the impedance value of the matching section so that impedance matching is achieved. In this example, the matching unit controller 31 controls the capacitance values of the variable capacitors C1 and C2.

  The load 5 is an apparatus for processing (etching, CVD, etc.) a workpiece such as a wafer and a liquid crystal substrate that is provided with a processing unit and is carried into the processing unit. In order to process the workpiece, the load 5 introduces a plasma discharge gas into the processing portion, and applies high-frequency power (voltage) supplied from a high-frequency power supply device to the plasma discharge gas. The plasma discharge gas is discharged (hereinafter referred to as plasma discharge) to change from a non-plasma state to a plasma state. And the workpiece is processed using the gas which became the plasma state. Such a load accompanied by discharge is called a discharge load. In addition, the discharge load has a characteristic that the load impedance changes suddenly before and after the start of discharge.

By the way, when impedance matching is performed between the high frequency power supply device 1p and the load 5, the high frequency power output from the high frequency power supply device 1p is efficiently supplied to the load 5.
However, since the internal impedance of the load 5 varies depending on the state of the plasma discharge, the impedance of the load varies to a high impedance or a low impedance as compared with the matching.
As a result, impedance matching between the high frequency power supply device 1p and the load 5 is not achieved, and the reflection coefficient at the input terminal 301 of the matching device increases, so that the high frequency power supply device 1p outputs to the load 5. Since a part or all of the traveling wave power that travels is reflected to generate reflected wave power PR that travels from the matching unit 3p to the high-frequency power supply device, the high-frequency power is not efficiently supplied to the load 5.

Usually, the impedance matching is performed by the matching device 3p to return to the matching state, but reflected wave power is generated until the matching state is changed to the matching state. Further, when the matching unit 3p is not optimally adjusted, the mismatching state may continue. The reflected wave power PR generated for the above reason returns into the high frequency power supply device.
JP 2001-197749 A JP 2003-143861 A

  In a high-frequency power supply apparatus that supplies high-frequency power to a load via the matching unit as described above, when a load whose load impedance changes suddenly before and after the start of discharge, such as a discharge load, is connected, the high-frequency power supply apparatus 1p The case where the traveling wave power or the load side power (traveling wave power-reflected wave power) output from the terminal is controlled to be constant will be described.

  When the high frequency power supply device 1p starts to output traveling wave power and the discharge load discharges, the matching unit changes the capacitance values of the variable capacitors C1 and C2 of the matching unit 32 in order to cope with a sudden change in load impedance. Perform the action.

  In the process of this matching operation, since the impedances of the variable capacitors C1 and C2 in the matching unit are changed, even if the high frequency power supply device operates to control the traveling wave power or the load side power to be constant, The voltage at the output terminal 302 of the matching unit 3p and the magnitude of the output current are changing. Therefore, in the matching process, the voltage applied to the load and the current value flowing through the load change.

  In the matching process, the discharge disappears when the voltage of the discharge load decreases to a level at which the discharge cannot be maintained, or the current value flowing through the discharge load decreases to a level at which the discharge cannot be maintained. When the discharge is extinguished, the reflection coefficient at the input terminal of the matching device increases, so that the matching device performs a matching operation so that the reflection coefficient becomes small. In this process, discharge cannot be performed again unless the voltage applied to the load reaches the discharge start voltage. When the discharge start voltage is reached and re-discharge is performed, the matching operation is continued. Thereafter, when the voltage of the discharge load becomes smaller than the discharge sustain voltage, the discharge disappears again, but if the voltage does not fall below the discharge sustain voltage, the discharge is maintained and the matching operation is continued.

  The same applies to the case where the current value flowing through the load decreases to a level at which the discharge cannot be maintained and the discharge disappears. If the current value flowing through the load does not reach the discharge start current, the discharge cannot be performed again. When the discharge start current is reached and re-discharge is performed, the matching operation is continued. Thereafter, when the value of the current flowing through the load becomes smaller than the discharge sustaining current, the discharge disappears again, but if the current value does not fall below the discharge sustaining current, the discharge is maintained and the matching operation is continued.

As described above, in the conventional high-frequency power supply device, when the load to be connected is a discharge load, the discharge may disappear between the start of the discharge and the alignment, and the processing process of the etching apparatus and the CVD apparatus using the discharge There was a problem of adversely affecting
The present invention has been made in view of the above problems, and an object of the present invention is to provide a high-frequency power supply device in which the disappearance of discharge does not occur in the matching process from the start of discharge.

As shown in FIG. 1, for example, the output power control method of the high frequency power supply provided by the present invention is as follows.
In an output power control method of a high frequency power source that supplies high frequency power to a load via a matching unit,
When the voltage detection value on the load side of the matching unit of the matching device is equal to or higher than the voltage setting value, the power detection value of the high frequency power is controlled to be equal to the power setting value,
When the voltage detection value on the load side of the matching unit of the matching unit is less than the voltage setting value, the power detection value of the high-frequency power is set to a value obtained by adding the command value for increasing the output of the high-frequency power to the power setting value. Control to be equal,
The voltage detection value on the load side of the matching unit of the matching unit is controlled so as not to be smaller than the voltage setting value.

For example, as shown in FIG. 2, the output power control method of another high frequency power supply provided by the present invention is as follows.
In an output power control method of a high frequency power source that supplies high frequency power to a load via a matching unit,
If the current detection value on the load side of the matching unit of the matching unit is equal to or greater than the current set value, control the power detection value of the high frequency power to be equal to the power set value,
When the current detection value on the load side of the matching unit of the matching unit is less than the current setting value, the power detection value of the high frequency power is set to a value obtained by adding the command value for increasing the output of the high frequency power to the power setting value. Control to be equal,
Control is performed so that the current detection value on the load side of the matching unit of the matching unit does not become smaller than the current set value.

For example, as shown in FIG. 3, the output power control method of another high frequency power source provided by the present invention is as follows.
In an output power control method of a high frequency power source that supplies high frequency power to a load via a matching unit,
When the voltage detection value on the load side of the matching unit of the matching device is equal to or higher than the voltage setting value, the power detection value of the high frequency power is controlled to be equal to the power setting value,
If the voltage detection value on the load side of the matching unit of the matching unit is less than the voltage setting value, the power detection value of the high frequency power is controlled to be equal to the command value for increasing the output of the high frequency power,
The voltage detection value on the load side of the matching unit of the matching unit is controlled so as not to be smaller than the voltage setting value.

For example, as shown in FIG. 4, the output power control method of another high-frequency power supply provided by the present invention is as follows.
In an output power control method of a high frequency power source that supplies high frequency power to a load via a matching unit,
If the current detection value on the load side of the matching unit of the matching unit is equal to or greater than the current set value, control the power detection value of the high frequency power to be equal to the power set value,
When the current detection value on the load side of the matching unit of the matching unit is less than the current setting value, the power detection value of the high frequency power is controlled to be equal to the command value for increasing the output of the high frequency power,
Control is performed so that the current detection value on the load side of the matching unit of the matching unit does not become smaller than the current set value.

  In the output power control method of the high frequency power supply, the command value for increasing the output of the high frequency power may be a value that changes according to a value obtained by subtracting the voltage detection value from the voltage setting value. The command value for increasing the output of the high-frequency power may be a value that changes according to a value obtained by subtracting the current detection value from the current setting value.

The high-frequency power supply device provided by the present invention is, for example, as shown in FIG.
In a high-frequency power supply device that supplies high-frequency power to a load via a matching unit,
A voltage detection unit that detects a voltage on the load side of the matching unit of the matching unit; and
The voltage detection value detected by the voltage detection unit is compared with a voltage setting value. When the voltage detection value is equal to or higher than the voltage setting value, a command value for increasing the output of high-frequency power is not output, and the voltage detection is performed. If the value is less than the voltage setting value, a voltage control unit that outputs a command value for increasing the output of the high-frequency power; and
A power detection unit that detects traveling wave power output from the high-frequency power supply device and directed to the load, or detects traveling wave power and reflected wave power reflected from the load side;
For controlling the load side power obtained by subtracting the reflected wave power from the traveling wave power detected by the power detection unit or the traveling wave power to be equal to a value obtained by adding the command value output from the voltage control unit to the power set value A power control unit that outputs a power control signal of
And an amplifying unit that outputs high-frequency power whose output value is increased or decreased according to a power control signal output from the power control unit.

Another high frequency power supply device provided by the present invention is, for example, as shown in FIG.
In a high-frequency power supply device that supplies high-frequency power to a load via a matching unit,
A current detection unit that detects a current on the load side of the matching unit of the matching unit;
The current detection value detected by the current detection unit is compared with a current setting value, and if the current detection value is equal to or greater than the current setting value, a command value for increasing the output of high-frequency power is not output, and the current detection If the value is less than the current set value, a current control unit that outputs a command value for increasing the output of the high-frequency power;
A power detection unit that detects traveling wave power output from the high-frequency power supply device and directed to the load, or detects traveling wave power and reflected wave power reflected from the load side;
In order to control so that the traveling wave power detected by the power detection unit or the load side power obtained by subtracting the reflected wave power from the traveling wave power is equal to the value obtained by adding the command value output from the current control unit to the power setting value A power control unit that outputs a power control signal of
And an amplifying unit that outputs high-frequency power whose output value is increased or decreased according to a power control signal output from the power control unit.

Another high frequency power supply device provided by the present invention is, for example, as shown in FIG.
In a high-frequency power supply device that supplies high-frequency power to a load via a matching unit,
A voltage detection unit that detects a voltage on the load side of the matching unit of the matching unit; and
The voltage detection value detected by the voltage detection unit is compared with a voltage setting value. When the voltage detection value is equal to or higher than the voltage setting value, a command value for increasing the output of high-frequency power is not output, and the voltage detection is performed. If the value is less than the voltage setting value, a voltage control unit that outputs a command value for increasing the output of the high-frequency power; and
A power detection unit that detects traveling wave power output from the high-frequency power supply device and directed to the load, or detects traveling wave power and reflected wave power reflected from the load side;
When the voltage detection value is equal to or higher than the voltage setting value, the traveling wave power detected by the power detection unit or the load side power obtained by subtracting the reflected wave power from the traveling wave power is controlled to be equal to the power setting value. When the voltage detection value is less than the voltage setting value, the traveling wave power detected by the power detection unit or the load side power obtained by subtracting the reflected wave power from the traveling wave power is the voltage control unit. A power control unit that outputs a power control signal for controlling to be equal to the command value output from
And an amplifying unit that outputs high-frequency power whose output value is increased or decreased according to a power control signal output from the power control unit.

Another high frequency power supply device provided by the present invention is, for example, as shown in FIG.
In a high-frequency power supply device that supplies high-frequency power to a load via a matching unit,
A current detection unit that detects a current on the load side of the matching unit of the matching unit;
The current detection value detected by the current detection unit is compared with a current setting value, and if the current detection value is equal to or greater than the current setting value, a command value for increasing the output of high-frequency power is not output, and the current detection If the value is less than the current set value, a current control unit that outputs a command value for increasing the output of the high-frequency power;
A power detection unit that detects traveling wave power output from the high-frequency power supply device and directed to the load, or detects traveling wave power and reflected wave power reflected from the load side;
When the current detection value is equal to or greater than the current setting value, the traveling wave power detected by the power detection unit or the load side power obtained by subtracting the reflected wave power from the traveling wave power is controlled to be equal to the power setting value. When the current detection value is less than the current setting value, the traveling wave power detected by the power detection unit or the load side power obtained by subtracting the reflected wave power from the traveling wave power is the current control unit. A power control unit that outputs a power control signal for controlling to be equal to the command value output from
And an amplifying unit that outputs high-frequency power whose output value is increased or decreased according to a power control signal output from the power control unit.

  In the high frequency power supply apparatus, the command value for increasing the output of the high frequency power may be a value that changes according to a value obtained by subtracting the voltage detection value from the voltage setting value. The command value for increasing the output of the high-frequency power may be a value that changes according to a value obtained by subtracting the current detection value from the current setting value.

Conventionally, when the load to be connected is a discharge load, the discharge may disappear between the start of discharge and the alignment, and there is a problem of adversely affecting the processing process of the etching apparatus and the CVD apparatus using the discharge. there were.
However, in the present invention, when the voltage detection value on the load side of the matching unit of the matching unit is less than the voltage setting value, the high frequency output is increased more than the power setting value, thereby increasing the load side of the matching unit of the matching unit. Since the voltage detection value is controlled so as not to be smaller than the voltage setting value, the discharge does not disappear from the start of the discharge to the matching state.
Alternatively, when the current detection value on the load side of the matching unit of the matching unit is less than the current setting value, the current detection value on the load side of the matching unit of the matching unit is increased by increasing the high-frequency output above the power setting value. Is controlled so as not to become smaller than the current set value, so that the discharge does not disappear from the start of the discharge until the matching state is reached.
For this reason, problems in processing processes that have occurred in the past can be solved.

  Hereinafter, details of the present invention will be described with reference to the drawings.

[First Embodiment]
FIG. 1 is a block diagram showing the configuration of the high-frequency power supply device 1a according to the first embodiment of the present invention, the configuration of the matching device 3a, and the connection relationship between the high-frequency power supply device 1a, the matching device 3a, and the load 5.

(Description of matcher)
The matching unit 3a according to the first embodiment of the present invention is different from the matching unit 3p of the prior art in that it includes a voltage detection unit 33 that detects an output voltage on the load side of the matching unit 32 of the matching unit. However, the rest is the same as the conventional matching device 3p, and is a device used for impedance matching between the high frequency power supply device 1a and the load 5. The voltage detection unit 33 detects an output voltage on the load side of the matching unit of the matching unit, and outputs a voltage detection signal Vv corresponding to the output voltage.

(Description of high frequency power supply)
A high frequency power supply device 1 a according to the first embodiment of the present invention is a power supply device for supplying high frequency power to a load 5 via a transmission line 2, a matching unit 3, and a load connection unit 4. In general, this type of high frequency power supply device outputs high frequency power having a frequency of several hundred kHz or more.

(Description of internal configuration of high frequency power supply device)
The oscillating unit 11 outputs a high-frequency signal Vos having a predetermined frequency. The high-frequency signal referred to here is not limited to a sine wave signal, and includes, for example, a rectangular wave signal, a triangular wave signal, and the like.

The amplifying unit 12 amplifies a high-frequency signal output from the oscillating unit 11 using an output signal of a power control unit 16a described later as an instruction value, and outputs traveling wave power PF.
The traveling wave power output from the amplifying unit 12 is output to the outside of the high frequency power supply device via the transmission line 2 connected to the high frequency power output connector 101 as an output end of the high frequency power supply device.

  The power detector 13 detects the traveling wave power PF output from the amplifying unit 12 and the reflected wave power PR returning from the outside of the high frequency power supply device, and the traveling wave power signal Vpf corresponding to the traveling wave power value and the reflected wave A reflected wave power signal Vpr corresponding to the wave power value is output. For example, a directional coupler is used for the power detection unit 13.

  The output voltage setting unit 17 outputs an output voltage setting signal Vvs that determines the output voltage setting value of the matching unit. In the case of a discharge load, the output voltage set value is preferably larger than the output voltage of the matching device when the load voltage is the discharge sustain voltage. The output voltage setting signal Vvs may be input from another device outside the high frequency power supply device.

  The voltage control unit 18 receives the voltage detection signal Vv output from the voltage detection unit 33 and the output voltage setting signal Vvs output from the output voltage setting unit 17, and outputs the voltage control signal Vvc to the power control unit 16a. . The voltage control signal Vvc is a 0V voltage signal when the magnitude of the voltage detection signal Vv is greater than or equal to the magnitude of the output voltage setting signal Vvs, and the magnitude of the voltage detection signal Vv is less than the magnitude of the output voltage setting signal Vvs. Sometimes it is a positive voltage signal. The magnitude of the positive voltage signal corresponds to a voltage value for setting the magnitude of the voltage detection signal Vv to the magnitude of the output voltage setting signal Vvs. The voltage detection signal Vv is input to the voltage control unit 18 via the output terminal 304 of the matching unit and the input terminal 102 of the high frequency power supply device.

  The output power setting unit 15 outputs an output power setting signal Vps that determines the output setting value of the traveling wave power PF output from the high frequency power supply device or the setting value of the load side power. The output power setting signal Vps may be input from another device outside the high frequency power supply device.

The power control unit 16a includes a traveling wave power signal Vpf and a reflected wave power signal Vpr output from the power detection unit 13, an output power setting signal Vps output from the output power setting unit 15, and a voltage output from the voltage control unit 18. A control signal Vvc is input. Further, when the traveling wave power is controlled to be constant, the traveling wave power signal Vpf corresponding to the traveling wave power value is used as the power detection signal Vp, and when the load side power is controlled to be constant, the reflected wave from the traveling wave power is reflected. A load-side power signal Vpl corresponding to the load-side power with reduced power is calculated, and this load-side power signal Vpl is set as a power detection signal Vp. It is determined in advance which of the traveling wave power signal Vpf and the load side power signal Vpl is the power detection signal Vp. Then, the power control signal Vpc1 serving as an instruction value is output to the amplifier so that the magnitude of the power detection signal Vp is equal to the magnitude of the output power setting signal Vps plus the voltage control signal Vvc.
When the above relationship is expressed by an arithmetic expression, Expression (1) is obtained.
Vpc1∝ (Vps + Vvc−Vp) (1)

That is, when the voltage detection value on the load side of the matching unit of the matching unit is equal to or higher than the voltage setting value, the power detection value is controlled to be equal to the power setting value.
On the other hand, when the voltage detection value on the load side of the matching unit of the matching unit is less than the voltage setting value, the power detection value changes to the power setting value according to the shortage (voltage setting value−voltage detection value). Control is performed so as to be equal to a value obtained by adding a command value for increasing the output of power, and control is performed so that the voltage detection value on the load side relative to the matching unit of the matching unit does not become smaller than the voltage setting value.

  In the case of an etching apparatus or a CVD apparatus that uses discharge, there are cases where discharge conditions (type of discharge gas, gas flow rate, pressure, etc.) are changed during discharge. For this reason, an optimum machining process can be performed by taking in a stable voltage that is equal to or higher than the discharge sustaining voltage under each discharge condition and the power required for the machining process as an output voltage set value and an output power set value, respectively. .

[Second Embodiment]
FIG. 2 is a block diagram showing the configuration of the high frequency power supply device 1b according to the second embodiment of the present invention, the configuration of the matching device 3b, and the connection relationship between the high frequency power supply device 1b, the matching device 3b, and the load 5.

(Description of matcher)
The matching unit 3b according to the second embodiment of the present invention is different from the matching unit 3p of the prior art in that it includes a current detection unit 34 that detects an output current flowing between the matching unit 32 and the load 5. However, the rest is the same as the conventional matching device 3p, and is a device used for impedance matching between the high frequency power supply device 1b and the load 5. The current detection unit 34 detects an output current that flows to the load side of the matching unit 32 of the matching unit, and outputs a current detection signal Vi corresponding to the output current.

(Description of high frequency power supply)
The high frequency power supply device 1b according to the second embodiment of the present invention is a power supply device for supplying high frequency power to the load 5 through the transmission line 2, the matching unit 3, and the load connecting portion 4. In general, this type of high frequency power supply device outputs high frequency power having a frequency of several hundred kHz or more.

(Description of internal configuration of high frequency power supply device)
The oscillating unit 11, the amplifying unit 12, the power detecting unit 13, and the output power setting unit 15 are the same as those of the high-frequency power supply device of FIG. 1 described in the first embodiment, and thus description thereof is omitted.

  The output current setting unit 20 outputs an output current setting signal Vis that determines the output current setting value of the matching unit. In the case of a discharge load, the output current set value is preferably larger than the output current of the matching device when the load current is the discharge sustaining current. The output current setting signal Vis may be input from another device outside the high frequency power supply device.

  The current control unit 21 receives the current detection signal Vi output from the current detection unit 34 and the output current setting signal Vis output from the output current setting unit 20, and outputs the current control signal Vic to the power control unit 16b. . The current control signal Vic is a voltage signal of 0V when the magnitude of the current detection signal Vi is greater than or equal to the magnitude of the output current setting signal Vis, and the magnitude of the current detection signal Vi is less than the magnitude of the output current setting signal Vis. Sometimes it is a positive voltage signal. The magnitude of the positive voltage signal corresponds to a voltage value for setting the magnitude of the current detection signal Vi to the magnitude of the output current setting signal Vis. The current detection signal Vi is input to the current control unit 21 via the output terminal 305 of the matching unit and the input terminal 103 of the high frequency power supply device.

The power control unit 16b includes a traveling wave power signal Vpf and a reflected wave power signal Vpr output from the power detection unit 13, an output power setting signal Vps output from the output power setting unit 15, and a current output from the current control unit 21. The control signal Vic is input. Further, when the traveling wave power is controlled to be constant, the traveling wave power signal Vpf corresponding to the traveling wave power value is used as the power detection signal Vp, and when the load side power is controlled to be constant, the reflected wave from the traveling wave power is reflected. A load-side power signal Vpl corresponding to the load-side power with reduced power is calculated, and this load-side power signal Vpl is set as a power detection signal Vp. It is determined in advance which of the traveling wave power signal Vpf and the load side power signal Vpl is the power detection signal Vp. Then, the power control signal Vpc2 serving as an instruction value is output to the amplifier so that the magnitude of the power detection signal Vp is equal to the magnitude obtained by adding the current control signal Vic to the output power setting signal Vps.
When the above relationship is expressed by an arithmetic expression, Expression (2) is obtained.
Vpc2∝ (Vps + Vic−Vp) (2)

That is, when the current detection value on the load side of the matching unit of the matching unit is equal to or greater than the current set value, control is performed so that the power detected value is equal to the power set value.
On the other hand, when the current detection value on the load side of the matching unit of the matching unit is less than the current setting value, the power detection value changes to the power setting value in accordance with the shortage (current setting value−current detection value). Control is performed so as to be equal to a value obtained by adding a command value for increasing the output of electric power, and control is performed so that the current detection value on the load side of the matching unit of the matching unit does not become smaller than the current set value.

  In the case of an etching apparatus or a CVD apparatus that uses discharge, there are cases where discharge conditions (type of discharge gas, gas flow rate, pressure, etc.) are changed during discharge. For this reason, an optimum machining process can be performed by taking in a stable current that is equal to or greater than the discharge sustaining current under each discharge condition and the power required for the machining process as an output current set value and an output power set value, respectively. .

[Third Embodiment]
FIG. 3 is a block diagram showing the configuration of the high-frequency power supply device 1c according to the third embodiment of the present invention, the configuration of the matching device 3a, and the connection relationship between the high-frequency power supply device 1c, the matching device 3a, and the load 5.

(Description of matcher)
The matching unit 3a is the same as that shown in FIG.

(Description of high frequency power supply)
In the high frequency power supply device 1c according to the third embodiment of the present invention, the power control unit 16a is changed to the power control unit 16c as compared with the high frequency power supply device 1a according to the first embodiment described in FIG. The point is different. Therefore, the power control unit 16c will be described. The rest of the configuration is the same as that of the high frequency power supply device of FIG.

The power control unit 16 c includes a traveling wave power signal Vpf and a reflected wave power signal Vpr output from the power detection unit 13, an output power setting signal Vps output from the output power setting unit 15, and a voltage output from the voltage control unit 18. A control signal Vvc is input. Further, when the traveling wave power is controlled to be constant, the traveling wave power signal Vpf corresponding to the traveling wave power value is used as the power detection signal Vp, and when the load side power is controlled to be constant, the reflected wave from the traveling wave power is reflected. A load-side power signal Vpl corresponding to the load-side power with reduced power is calculated, and this load-side power signal Vpl is set as a power detection signal Vp. It is determined in advance which of the traveling wave power signal Vpf and the load side power signal Vpl is the power detection signal Vp.
When the voltage control signal Vvc is a voltage signal of 0V, the power control signal Vpc3 serving as an instruction value is output to the amplifier so that the magnitude of the power detection signal Vp is equal to the magnitude of the output power setting signal Vps. When the voltage control signal Vvc is a positive voltage signal, the power control signal Vpc3 serving as an instruction value is output to the amplifier so that the magnitude of the power detection signal Vp is equal to the magnitude of the voltage control signal Vvc.
When the above relationship is expressed by an arithmetic expression, Expression (3) is obtained when the output voltage of the matching device 3a is equal to or higher than the voltage setting value, and Expression (4) is obtained when the output voltage of the matching device 3a is less than the voltage setting value. .
Vpc3∝ (Vps-Vp) (3)
Vpc3∝ (Vvc−Vp) (4)

That is, when the voltage detection value on the load side of the matching unit of the matching unit is equal to or higher than the voltage setting value, the power detection value is controlled to be equal to the power setting value.
On the other hand, when the voltage detection value on the load side of the matching unit of the matching unit is less than the voltage setting value, the power detection value is an output of high-frequency power that changes according to the shortage (voltage setting value−voltage detection value). Control is performed so as to be equal to the command value for increase, and control is performed so that the voltage detection value on the load side of the matching unit of the matching unit does not become smaller than the voltage setting value.

  In the case of an etching apparatus or a CVD apparatus that uses discharge, there are cases where discharge conditions (type of discharge gas, gas flow rate, pressure, etc.) are changed during discharge. For this reason, an optimum machining process can be performed by taking in a stable voltage that is equal to or higher than the discharge sustaining voltage under each discharge condition and the power required for the machining process as an output voltage set value and an output power set value, respectively. .

[Fourth Embodiment]
FIG. 4 is a block diagram showing the configuration of the high frequency power supply device 1d according to the fourth embodiment of the present invention, the configuration of the matching device 3b, and the connection relationship between the high frequency power supply device 1d, the matching device 3b, and the load 5.

(Description of matcher)
The matching unit 3b is the same as that shown in FIG.

(Description of high frequency power supply)
In the high frequency power supply device 1d according to the fourth embodiment of the present invention, the power control unit 16b is changed to the power control unit 16d as compared with the high frequency power supply device 1b according to the second embodiment described in FIG. The point is different. Therefore, the power control unit 16d will be described. The rest of the configuration is the same as that of the high frequency power supply device of FIG.

The power control unit 16d is a traveling wave power signal Vpf and a reflected wave power signal Vpr output from the power detection unit 13, an output power setting signal Vps output from the output power setting unit 15, and a current output from the current control unit 21. The control signal Vic is input. Further, when the traveling wave power is controlled to be constant, the traveling wave power signal Vpf corresponding to the traveling wave power value is used as the power detection signal Vp, and when the load side power is controlled to be constant, the reflected wave from the traveling wave power is reflected. A load-side power signal Vpl corresponding to the load-side power with reduced power is calculated, and this load-side power signal Vpl is set as a power detection signal Vp. It is determined in advance which of the traveling wave power signal Vpf and the load side power signal Vpl is the power detection signal Vp.
When the current control signal Vic is a voltage signal of 0V, the power control signal Vpc4 serving as an instruction value is output to the amplifier so that the magnitude of the power detection signal Vp is equal to the magnitude of the output power setting signal Vps. When the current control signal Vic is a positive voltage signal, the power control signal Vpc4 serving as an instruction value is output to the amplifier so that the magnitude of the power detection signal Vp is equal to the magnitude of the current control signal Vic.
When the above relationship is expressed by an arithmetic expression, Expression (5) is obtained when the output current of the matching unit 3b is equal to or greater than the current set value, and Expression (6) is obtained when the output current of the matching unit 3b is less than the current set value. .
Vpc4∝ (Vps-Vp) (5)
Vpc4∝ (Vic-Vp) (6)

That is, when the current detection value on the load side of the matching unit of the matching unit is equal to or greater than the current set value, control is performed so that the power detected value is equal to the power set value.
On the other hand, when the current detection value on the load side of the matching unit of the matching unit is less than the current setting value, the power detection value is an output of high-frequency power that changes according to the shortage (current setting value−current detection value). Control is performed so as to be equal to the command value for increase, and control is performed so that the current detection value on the load side relative to the matching unit of the matching unit does not become smaller than the current set value.

  In the case of an etching apparatus or a CVD apparatus that uses discharge, there are cases where discharge conditions (type of discharge gas, gas flow rate, pressure, etc.) are changed during discharge. For this reason, an optimum machining process can be performed by taking in a stable current that is equal to or greater than the discharge sustaining current under each discharge condition and the power required for the machining process as an output current set value and an output power set value, respectively. .

  In FIG. 1 and FIG. 3, the voltage detector is provided inside the matching unit to detect the output voltage of the matching unit, but the voltage at both ends of the load may be detected. 2 and 4, the current detector is provided inside the matching unit to detect the output current of the matching unit. However, the current flowing through the load may be detected.

FIG. 1 is a block diagram showing the configuration of the high-frequency power supply device 1a according to the first embodiment of the present invention, the configuration of the matching device 3a, and the connection relationship between the high-frequency power supply device 1a, the matching device 3a, and the load 5. FIG. 2 is a block diagram showing the configuration of the high frequency power supply device 1b according to the second embodiment of the present invention, the configuration of the matching device 3b, and the connection relationship between the high frequency power supply device 1b, the matching device 3b, and the load 5. FIG. 3 is a block diagram showing the configuration of the high-frequency power supply device 1c according to the third embodiment of the present invention, the configuration of the matching device 3a, and the connection relationship between the high-frequency power supply device 1c, the matching device 3a, and the load 5. FIG. 4 is a block diagram showing the configuration of the high frequency power supply device 1d according to the fourth embodiment of the present invention, the configuration of the matching device 3b, and the connection relationship between the high frequency power supply device 1d, the matching device 3b, and the load 5. FIG. 5 is a block diagram showing the configuration of the conventional high-frequency power supply device 1p, the configuration of the matching device 3p, and the connection relationship between the high-frequency power supply device 1p, the matching device 3p, and the load 5.

Explanation of symbols

1a High-frequency power supply device 1b according to the first embodiment of the present invention High-frequency power supply device 1c according to the second embodiment of the present invention High-frequency power supply device 1d according to the third embodiment of the present invention Fourth embodiment of the present invention High-frequency power supply device 1p according to the configuration Conventional high-frequency power supply device 2 Transmission line 3a Matching device 3b according to the first and third embodiments of the present invention Matching device 3p according to the second and fourth embodiments of the present invention Matching unit 4 Load connection unit 5 Load 11 Oscillation unit 12 Amplification unit 13 Power detection unit 15 Output power setting unit 16 Power control unit 17 Output voltage setting unit 18 Voltage control unit 20 Output current setting unit 21 Current control unit 22 Voltage current selection unit 31 Matching Unit Control Unit 32 Matching Unit 33 Voltage Detection Unit 34 Current Detection Unit

Claims (12)

In an output power control method of a high frequency power source that supplies high frequency power to a load via a matching unit,
When the voltage detection value on the load side of the matching unit of the matching device is equal to or higher than the voltage setting value, the power detection value of the high frequency power is controlled to be equal to the power setting value,
When the voltage detection value on the load side of the matching unit of the matching unit is less than the voltage setting value, the power detection value of the high-frequency power is set to a value obtained by adding the command value for increasing the output of the high-frequency power to the power setting value. Control to be equal,
An output power control method for a high-frequency power source, wherein control is performed so that a voltage detection value on a load side of a matching unit of a matching device does not become smaller than a voltage setting value. In an output power control method of a high frequency power source that supplies high frequency power to a load via a matching unit,
If the current detection value on the load side of the matching unit of the matching unit is equal to or greater than the current set value, control the power detection value of the high frequency power to be equal to the power set value,
When the current detection value on the load side of the matching unit of the matching unit is less than the current setting value, the power detection value of the high frequency power is set to a value obtained by adding the command value for increasing the output of the high frequency power to the power setting value. Control to be equal,
An output power control method for a high-frequency power source, wherein control is performed so that a current detection value on a load side of a matching unit of a matching unit does not become smaller than a current set value. In an output power control method of a high frequency power source that supplies high frequency power to a load via a matching unit,
When the voltage detection value on the load side of the matching unit of the matching device is equal to or higher than the voltage setting value, the power detection value of the high frequency power is controlled to be equal to the power setting value,
If the voltage detection value on the load side of the matching unit of the matching unit is less than the voltage setting value, the power detection value of the high frequency power is controlled to be equal to the command value for increasing the output of the high frequency power,
An output power control method for a high-frequency power source, wherein control is performed so that a voltage detection value on a load side of a matching unit of a matching device does not become smaller than a voltage setting value. In an output power control method of a high frequency power source that supplies high frequency power to a load via a matching unit,
If the current detection value on the load side of the matching unit of the matching unit is equal to or greater than the current set value, control the power detection value of the high frequency power to be equal to the power set value,
When the current detection value on the load side of the matching unit of the matching unit is less than the current setting value, the power detection value of the high frequency power is controlled to be equal to the command value for increasing the output of the high frequency power,
An output power control method for a high-frequency power source, wherein control is performed so that a current detection value on a load side of a matching unit of a matching unit does not become smaller than a current set value. 4. The output power of the high frequency power supply according to claim 1, wherein a command value for increasing the output of the high frequency power changes according to a value obtained by subtracting a voltage detection value from a voltage setting value. 5. Control method. 5. The output power of the high-frequency power source according to claim 2, wherein a command value for increasing the output of the high-frequency power changes according to a value obtained by subtracting a current detection value from a current setting value. Control method. In a high-frequency power supply device that supplies high-frequency power to a load via a matching unit,
A voltage detection unit that detects a voltage on the load side of the matching unit of the matching unit; and
The voltage detection value detected by the voltage detection unit is compared with a voltage setting value. When the voltage detection value is equal to or higher than the voltage setting value, a command value for increasing the output of high-frequency power is not output, and the voltage detection is performed. If the value is less than the voltage setting value, a voltage control unit that outputs a command value for increasing the output of the high-frequency power; and
A power detection unit that detects traveling wave power output from the high-frequency power supply device and directed to the load, or detects traveling wave power and reflected wave power reflected from the load side;
For controlling the load side power obtained by subtracting the reflected wave power from the traveling wave power detected by the power detection unit or the traveling wave power to be equal to a value obtained by adding the command value output from the voltage control unit to the power set value A power control unit that outputs a power control signal of
A high-frequency power supply apparatus comprising: an amplifying unit that outputs high-frequency power whose output value is increased or decreased according to a power control signal output from the power control unit. In a high-frequency power supply device that supplies high-frequency power to a load via a matching unit,
A current detection unit that detects a current on the load side of the matching unit of the matching unit;
The current detection value detected by the current detection unit is compared with a current setting value, and if the current detection value is equal to or greater than the current setting value, a command value for increasing the output of high-frequency power is not output, and the current detection If the value is less than the current set value, a current control unit that outputs a command value for increasing the output of the high-frequency power;
A power detection unit that detects traveling wave power output from the high-frequency power supply device and directed to the load, or detects traveling wave power and reflected wave power reflected from the load side;
In order to control so that the traveling wave power detected by the power detection unit or the load side power obtained by subtracting the reflected wave power from the traveling wave power is equal to the value obtained by adding the command value output from the current control unit to the power setting value A power control unit that outputs a power control signal of
A high-frequency power supply apparatus comprising: an amplifying unit that outputs high-frequency power whose output value is increased or decreased according to a power control signal output from the power control unit. In a high-frequency power supply device that supplies high-frequency power to a load via a matching unit,
A voltage detection unit that detects a voltage on the load side of the matching unit of the matching unit; and
The voltage detection value detected by the voltage detection unit is compared with a voltage setting value. When the voltage detection value is equal to or higher than the voltage setting value, a command value for increasing the output of high-frequency power is not output, and the voltage detection is performed. If the value is less than the voltage setting value, a voltage control unit that outputs a command value for increasing the output of the high-frequency power; and
A power detection unit that detects traveling wave power output from the high-frequency power supply device and directed to the load, or detects traveling wave power and reflected wave power reflected from the load side;
When the voltage detection value is equal to or higher than the voltage setting value, the traveling wave power detected by the power detection unit or the load side power obtained by subtracting the reflected wave power from the traveling wave power is controlled to be equal to the power setting value. When the voltage detection value is less than the voltage setting value, the traveling wave power detected by the power detection unit or the load side power obtained by subtracting the reflected wave power from the traveling wave power is the voltage control unit. A power control unit that outputs a power control signal for controlling to be equal to the command value output from
A high-frequency power supply apparatus comprising: an amplifying unit that outputs high-frequency power whose output value is increased or decreased according to a power control signal output from the power control unit. In a high-frequency power supply device that supplies high-frequency power to a load via a matching unit,
A current detection unit that detects a current on the load side of the matching unit of the matching unit;
The current detection value detected by the current detection unit is compared with a current setting value, and if the current detection value is equal to or greater than the current setting value, a command value for increasing the output of high-frequency power is not output, and the current detection If the value is less than the current set value, a current control unit that outputs a command value for increasing the output of the high-frequency power;
A power detection unit that detects traveling wave power output from the high-frequency power supply device and directed to the load, or detects traveling wave power and reflected wave power reflected from the load side;
When the current detection value is equal to or greater than the current setting value, the traveling wave power detected by the power detection unit or the load side power obtained by subtracting the reflected wave power from the traveling wave power is controlled to be equal to the power setting value. When the current detection value is less than the current setting value, the traveling wave power detected by the power detection unit or the load side power obtained by subtracting the reflected wave power from the traveling wave power is the current control unit. A power control unit that outputs a power control signal for controlling to be equal to the command value output from
A high-frequency power supply apparatus comprising: an amplifying unit that outputs high-frequency power whose output value is increased or decreased according to a power control signal output from the power control unit. 10. The high frequency power supply device according to claim 7, wherein a command value for increasing the output of the high frequency power changes according to a value obtained by subtracting a voltage detection value from a voltage setting value. 11. 11. The high frequency power supply apparatus according to claim 8, wherein a command value for increasing the output of the high frequency power changes according to a value obtained by subtracting a current detection value from a current set value.

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