TW201424463A - Plasma emission device and substrate processing device - Google Patents

Abstract

A plasma emission device (2) which emits plasma by supplying RF electricity to a plasma generation electrode (3) comprises: an RF oscillator (31) which is capable of changing an oscillating RF frequency; an RF electricity emitter (32) which amplifies the frequency RF which is oscillated from the RF oscillator (31) and emits RF electricity; a transmission path (33) which transmits the RF electricity from the RF electricity emitter (32) to the plasma generation electrode (3); a matcher (34) which is disposed upon the transmission path (33) for impedance matching; a directional coupler (35) which is disposed upon the transmission path (33); and a detector (36) which detects a spectrum of a reflected wave which is guided via the directional coupler (35), and sends feedback of a reflected component of a base frequency within the spectrum to the matcher (34).

Description

Plasma generating device and substrate processing device

The present invention relates to a plasma generating apparatus and a substrate processing apparatus using the same.

2. In the past, it was known that a parallel plate type plasma processing device is provided with an anode in a chamber. The cathode electrode is supplied with high-frequency power from the high-frequency power generator (high-frequency power source) provided outside the chamber via an impedance matching device (matcher) to the cathode electrode (for example, Patent Document 1).

When such a parallel plate type plasma processing apparatus is applied to a plasma processing such as a film forming process or an etching process of a glass substrate such as a solar panel or a flat panel, a high frequency (RF) frequency (RF frequency) is applied. It is fixed to one type such as 13.56 MHz, and the plasma treatment is performed by using the type of the processing gas, the flow rate, the pressure, the distance between the electrodes, the high-frequency power, and the like as program parameters.

[Previous Technical Literature] [Patent Document]

[Patent Document 1] Japanese Patent Laid-Open No. 61-119686

Among them, when a parallel plate type plasma processing apparatus is used for, for example, a CVD (Chemical Vapor Deposition) device of a solar panel, it is known that frequency can be an effective program parameter for controlling plasma density or increasing crystallinity, etc. Change the frequency in each program.

However, in the plasma processing apparatus of the parallel plate type, in the conventional state, the high frequency power generator or the impedance matching device (matcher) must use a dedicated device for each frequency, and if it is desired to change the frequency, depending on the situation, The high frequency generator for each frequency must be replaced with an RF coaxial cable, etc., so the RF frequency is not changed during the mass production phase.

Accordingly, an object of the present invention is to provide a plasma generating apparatus capable of changing an RF frequency without replacing a high frequency power generator or an impedance matching device, and a substrate processing apparatus using the same.

In other words, according to a first aspect of the present invention, a plasma generating apparatus for generating a plasma by supplying high frequency electric power to a plasma generating electrode is provided, and the plasma generating apparatus includes a high frequency oscillator and can be changed. a frequency of a high frequency of oscillation; a high frequency power generator that amplifies a high frequency of a frequency oscillated by the high frequency oscillator and generates high frequency power; and a transmission line that transmits high frequency power from the high frequency power generator to The plasma generating electrode; the impedance matching device is disposed on the transmission line, and the generated plasma load impedance is matched with the impedance of the transmission line on the high frequency power generator side; the directional coupler is disposed in the transmission The aforementioned high frequency electricity Between the force generator and the aforementioned impedance matching device; the detector detects the spectrum of the guided reflected wave via the directional coupler, and feeds back the reflected component of the fundamental frequency to the impedance matcher.

Further, the plasma generating apparatus according to the first aspect of the invention may further include: a pass-through type power sensor provided between the high-frequency power generator of the transmission line and the impedance matching device; and a power meter; The signal from the pass-through power sensor is fed back to the aforementioned high frequency generator.

Also, a spectrum analyzer can be used as the aforementioned detector. Further, as the aforementioned detector, a Fourier transform function having a spectrum in which an input signal is converted into a digital signal and subjected to fast Fourier transform and frequency is obtained can be used.

According to a second aspect of the present invention, a substrate processing apparatus for processing a substrate through a plasma of a processing gas generated by high-frequency power, the substrate processing apparatus comprising: a chamber for accommodating the substrate and being held under vacuum; a plasma generating electrode is provided in the chamber, and is supplied with high-frequency electric power to generate plasma; a plasma generating device supplies high-frequency electric power to the plasma generating electrode to generate plasma; and a processing gas supply mechanism to the chamber The processing gas is supplied, and the plasma generating device includes a high frequency oscillator that changes a frequency of a high frequency that oscillates, and a high frequency power generator that amplifies a high frequency of a frequency oscillated by the high frequency oscillator. a high frequency power; a transmission line for transmitting high frequency power from the high frequency power generator to the plasma generating electrode; and an impedance matching device disposed on the transmission line to generate a plasma load impedance and the high frequency power generated The aforementioned pass The impedance of the transmission line is matched; the directional coupler is disposed between the high frequency power generator of the transmission line and the impedance matching device; and the detector detects the spectrum of the guided reflected wave via the directional coupler And returning the reflected component of the fundamental frequency therein to the aforementioned impedance matcher.

In the substrate processing apparatus according to the second aspect of the invention, the plurality of plasma generating electrodes are provided corresponding to the plurality of substrates, and the plasma generated by supplying the high-frequency power to the respective plasma generating electrodes from the plasma generating device , capable of processing a plurality of substrates.

In the present invention, the reflected wave passing through the impedance matching device is guided to the detector by the directional coupler, and the spectrum of the reflected wave is detected by the detector, and the detector feeds back the reflection component of the fundamental frequency to the impedance. Matcher. Thereby, the reflection component and the high harmonic component of the fundamental frequency can be accurately separated, and in fact only the reflection component of the fundamental frequency is fed back to the impedance matcher. Therefore, even when the frequency is made variable, high-precision tuning can be performed in the impedance matching device. Since high-precision tuning can be performed in this way, the RF frequency can be changed without replacing the high-frequency power generator or the impedance matching device, and a program for changing the frequency can be performed in practical use.

1‧‧‧ chamber

2‧‧‧ Plasma generating device

3‧‧‧Cathode electrode (upper electrode)

4‧‧‧Anode electrode (lower electrode)

5‧‧‧Process Gas Supply Department

6‧‧‧Exhaust Department

7‧‧‧Control Department

10‧‧‧ sprinkler

14‧‧‧heater

15‧‧‧Processing gas supply mechanism

18‧‧‧Exhaust device

31‧‧‧External Oscillator

32‧‧‧High frequency power generator

33‧‧‧Transmission line

34‧‧‧impedance matcher

35‧‧‧ Directional Coupler

36‧‧‧Spectrum Analyzer

37‧‧‧ Pass-through power sensor

38‧‧‧Power meter

100,200‧‧‧ substrate processing device

S‧‧‧Substrate

Fig. 1 is a cross-sectional view showing a substrate processing apparatus according to a first embodiment of the present invention.

Fig. 2 is a view showing a circuit configuration of an impedance matching device.

[Fig. 3] A high-harmonic component is a graph showing a frequency spectrum when an excessively high second harmonic component is output as compared with a fundamental frequency component as a result of a low-pass filter not being sufficiently attenuated.

FIG. 4 is a view showing an output waveform of FIG. 3. FIG.

Fig. 5 is a view showing a suitable output waveform.

Fig. 6 is a cross-sectional view showing a substrate processing apparatus according to a second embodiment of the present invention.

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

<First embodiment>

Hereinafter, the first embodiment will be described. Fig. 1 is a cross-sectional view showing a substrate processing apparatus according to a first embodiment of the present invention.

The substrate processing apparatus 100 is configured as a parallel plate type plasma processing apparatus. The substrate processing apparatus 100 includes a chamber 1 that houses a substrate S and performs plasma processing, a plasma generating device 2, a cathode electrode 3 and an anode electrode 4, and constitutes a parallel plate electrode provided in the chamber 1; a processing gas supply unit 5. The processing gas is supplied into the chamber 1; the exhaust unit 6 exhausts the inside of the chamber 1, and the control unit 7 controls each component of the substrate processing apparatus 100.

The cathode electrode 3 is configured as an upper electrode and functions as a plasma generating electrode to which high-frequency power is supplied. Further, the cathode electrode 3 has a gas diffusion space 3a inside, and a gas discharge hole 3b from which the gas The body diffusion space 3a is provided in the chamber 1 to constitute a head 10 that forms a part of the gas supply unit 5. The cathode electrode 3 is supported on the top wall of the chamber 1 via the insulating member 12.

On the other hand, the anode electrode 4 is configured as a lower electrode and functions as a mounting table on which the substrate S is placed. Further, a heater 14 is embedded in the anode electrode 4, and power is supplied from a power source (not shown) to the heater 14, whereby the heater 14 generates heat and the substrate S on the anode electrode 4 is heated to a predetermined temperature. The anode electrode 4 is supported on the bottom wall of the chamber 1 via the insulating member 13. The anode electrode 4 is grounded. In addition, the distance between the cathode electrode 3 and the anode electrode 4 can also be adjusted.

The processing gas supply unit 5 includes a processing gas supply unit 15 that supplies a processing gas, a processing gas supply path 16 that guides the processing gas from the head 10 and the processing gas supply unit 15 to the shower head 10.

The exhaust unit 6 includes an exhaust pipe 17 connected to the bottom of the chamber 1 and an exhaust device 18 composed of a vacuum pump connected to the exhaust pipe 17; an automatic pressure control valve (APC) 19 for controlling the device The pressure in the chamber 1 in the middle of the exhaust pipe 17.

The loading/unloading port 20 for carrying in and carrying out the substrate S is provided in the side wall of the chamber 1, and the loading/unloading port 20 is switchable by the gate valve 21.

The plasma generating device 2 has an external oscillator (high frequency oscillator) 31, a high frequency power generator 32, a transmission line 33, an impedance matching unit 34, a directional coupler 35, a spectrum analyzer (detector) 36, and a pass. Over-type power sensor 37 and power meter 38.

The external oscillator (high frequency oscillator) 31 generates high frequency oscillation and can change the frequency of the oscillated high frequency. The high frequency power generator 32 amplifies the high frequency of the frequency oscillated by the external oscillator 31 and generates high frequency power. The transmission line 33 transmits high frequency power from the high frequency power generator 32 to the cathode electrode 3. The impedance matching unit 34 is provided on the transmission line 33 to match the plasma load impedance generated in the chamber 1 with the impedance of the transmission line 33 on the high-frequency power generator 32 side. The directional coupler 35 is disposed between the high frequency power generator 32 of the transmission line 33 and the impedance matcher 34. The spectrum analyzer 36 detects the spectrum of the guided reflected wave via the directional coupler 35 and feeds back the reflected component of the fundamental frequency to the impedance matcher 34. The pass-through power sensor 37 is disposed between the high-frequency power generator 32 of the transmission line 33 and the impedance matcher 34. The power meter 38 measures the signal from the pass-through power sensor 37 and feeds back to the high-frequency generation. 32.

The external oscillator 31 has an external interface, and the frequency can be made variable by remote control. Further, the high-frequency power generator 32 amplifies the high frequency oscillated by the external oscillator 31 by the C-stage or AB-stage analog amplifier. In the high frequency power generator 32, a low pass filter (LPF) 32a for attenuating high harmonics is provided.

The external oscillator 31 can be mounted in the same casing as the high-frequency power generator 32. Further, the high frequency power generator 32 may have a variable frequency function of the external oscillator 31. Since the circuit constant of the low pass filter (LPF) 32a provided in the high frequency power generator 32 is fixed, Thus, in the case where the frequency is made variable, the cutoff frequency will become inconsistent with the output frequency, and the high harmonic component that cannot be attenuated by the low pass filter (LPF) 32a will be generated from the high frequency power generator 32. .

The transmission line 33 is constituted by a coaxial cable. Further, as shown in FIG. 2, the impedance matching unit 34 has a transmission line 41 connected to the input side and the output side of the transmission line 33, and a first variable capacitor 43 which is branched from the branching point 42 of the transmission line 41; The second variable capacitor 44 is provided on the output side of the branching point 42 of the transmission line 41; the coil (inductor) 45 is provided on the input side of the branching point 42. Further, according to the detected value of the built-in RF sensor (not shown), the position (capacity) of the first variable capacitor 43 and the second variable capacitor 44 can be automatically adjusted, and the transmission line 33 can be automatically matched. Impedance (50Ω) and plasma load impedance. The transmission line 33 on the outlet side of the impedance matching unit 34 is connected to the center of the upper surface of the cathode electrode 3.

The directional coupler 35 is inserted into the transmission line 33, and the reflected wave of the propagation transmission line 33 is taken out to other sputum, and the spectrum analyzer 36 is connected to the other port.

The spectrum analyzer 36 is reflected by the plasma, and after passing through the impedance matching unit 34, the spectrum of the signal including the high harmonics obtained via the directional coupler 35 can be obtained, from which only the fundamental frequency is taken out. The component is reflected and the signal is fed back to the impedance matcher 34. Thereby, in the impedance matching unit 34, it is possible to perform tuning in which only the fundamental frequency is detected. Regarding the RF sensor existing in the impedance matching unit 34, when the frequency is made variable, there is a case where the reflection component and the high harmonic component of the fundamental frequency cannot be accurately separated, and thus, by using the directional coupler 35 and spectrum The analyzer 36 is capable of accurately detecting only the fundamental frequency and is capable of performing high-precision tuning in the impedance matching unit 34.

As the spectrum analyzer 36, an FFT method having a fast Fourier transform (FFT) function is preferred. The FFT method converts the input signal into a digital signal and performs fast Fourier transform with the CPU to obtain the frequency spectrum, that is, the frequency and amplitude information.

The pass type power sensor 37 detects the high frequency power (power) in the transmission line 33. In general, pass-through power sensors are more accurate than power sensors built into high-frequency power generators. Therefore, in the pass type power sensor 37, compared with the high frequency power generator 32, the high frequency power (power) of the high harmonic overlap can be more accurately recognized. Therefore, the pass-through type power sensor 37 is provided on the transmission line 33, and the signal is fed back to the high-frequency power generator 32 via the power meter 38. By using it in power control and reflected wave control, the frequency can be set to be increased. Variable power accuracy.

The control unit 7 controls each component of the substrate processing apparatus 100, and includes a controller including a microprocessor, a user interface, a keyboard for observing an input operation command of the substrate processing apparatus 100, and the like, and an observable A display or the like that displays the operation state of the substrate processing apparatus 100; the memory unit is applied to control processing or processing conditions for realizing various processes executed by the substrate processing apparatus 100 under control of the controller, and is stored for processing on the substrate. The device 100 executes a processing program of a predetermined process. The processing program and the like are memorized in the memory medium, and are read and executed from the memory medium in the memory unit. Memory media can also be hard disk or semiconductor memory. It can be a portable device such as a CD-ROM, a DVD, or a flash memory. The processing program or the like is read from the memory unit and executed by the controller by an instruction from the user's face, etc., thereby performing the desired processing in the substrate processing apparatus 100 under the control of the controller. Processing.

Next, the processing operation of the substrate processing apparatus 100 having this configuration will be described.

Initially, the gate valve 21 is opened, and the substrate S is carried into the chamber 1 from the loading/unloading port 20 by a transfer device (not shown), and placed on the anode electrode 4 functioning as a mounting table. The conveyance device is retracted from the chamber 1, and after the gate valve 21 is closed, the inside of the chamber 1 is exhausted by the exhaust device 18, and the chamber is brought into a predetermined vacuum environment. At this time, the substrate S on the anode electrode 4 is heated to a predetermined temperature by the heater 14.

Further, the processing gas supply means 15 discharges the processing gas into the chamber 1 through the processing gas supply path 16 and the head 10, and simultaneously supplies the high-frequency power from the high-frequency power generator 32 to the cathode electrode 3.

Thereby, a high-frequency electric field is generated between the cathode electrode 3 and the anode electrode 4 opposed to each other, and the plasma of the processing gas generated by the high-frequency electric field is transmitted through the substrate S heated by the heater 14. A predetermined plasma treatment such as plasma CVD.

In the present embodiment, the frequency of the high-frequency power output by the high-frequency power generator 32 by the external oscillator 31 is variable. For example, when the frequency of the reference of the high-frequency power generator 32 is 13.56 MHz, a frequency change of about ±3 MHz can be generated. In the high frequency power generator 32 In the middle, a low-pass filter 32a for setting a high harmonic with respect to a fundamental frequency of a reference frequency (for example, when the fundamental frequency is 10 MHz, 20 MHz, 30 MHz, or the like) is provided. Although the attenuation is constant, when the frequency is changed from the reference frequency, high harmonics that cannot be completely attenuated by the low-pass filter (LPF) 32a are generated.

For example, as shown in the spectrum of FIG. 3, the high harmonic component is not sufficiently attenuated by the low pass filter (LPF) 32a, and the output from the high frequency power generator 32 is too high as compared with the fundamental frequency component. Second harmonic component. The output waveform at this time becomes as shown in FIG. 4, and distortion is generated as compared with an appropriate output waveform shown in FIG. 5 in which the harmonic component is sufficiently attenuated and substantially sinusoidal.

As described above, high-frequency power generator 32 generates high harmonics that cannot be completely attenuated by the low-pass filter (LPF) 32a, and high harmonics are generated from the plasma load, and the waves are transmitted in the transmission line 33. It is synthesized and causes problems when the impedance matcher 34 performs tuning. That is, the tuning is preferably performed at a fundamental frequency (which is a changed frequency in the case where the frequency is changed). In the impedance matching unit 34, only the fundamental frequency is sensed and performed by the RF sensor. Tuning, in general, the RF sensor of the impedance matcher has poor frequency characteristics (low Q), so that the high harmonic component cannot be removed in the case of containing a high harmonic component generated when the frequency is variable. Therefore, its high harmonic component reacts to the detector of the impedance matcher 34 and causes problems in tuning, and thus becomes difficult to match.

Therefore, in the present embodiment, the directional coupler 35 directs the reflected wave through the impedance matcher 34 to the spectrum analyzer 36, and detects the spectrum of the reflected wave, so that the reflected component of the fundamental frequency is fed back to the impedance matcher 34. The spectrum analyzer 36 is capable of accurately separating the reflection component and the high harmonic component of the fundamental frequency, and actually only the reflection component of the fundamental frequency thereof is fed back to the impedance matcher 34, so even in the case where the frequency is made variable, High-precision tuning can also be performed at the impedance matcher 34.

Since high-precision tuning can be performed in this way, the RF frequency can be changed without replacing the high-frequency power generator or the impedance matching device, and a program for changing the frequency can be performed in practical use.

For example, when it is desired to increase the plasma density, in particular, in order to increase the film formation rate in CVD film formation, it is preferable to increase the RF frequency and perform product processing, and for example, in CVD processing of solar panels, It is preferable to reduce the RF frequency and to carry out product processing in the case of increasing the crystallization ratio.

In addition, the signal from the directional coupler 35 can be effectively utilized as a condition of a new program or as a failure analysis or monitoring of an RF signal.

Further, as described above, since various types of high harmonics are reflected by the plasma and returned to the high frequency power generator 32, it is sometimes impossible to read the correct traveling wave by the power sensor of the high frequency power generator 32. The case of reflected waves. In particular, the situation is more pronounced when the frequency is changed and the frequency is operated at a frequency other than the originally adjusted frequency.

This problem can be eliminated by setting the pass-through power sensor 37. As mentioned above, usually, the pass type power sensor is built in high frequency electricity. The power sensor of the force generator is more precise. Therefore, in the pass type power sensor 37, compared with the high frequency power generator 32, the high frequency power (power) of the high harmonic overlap can be more accurately recognized. Therefore, the signal detected by the pass-through power sensor 37 is fed back to the high-frequency power generator 32 via the power meter 38, and by using this for power control and reflected wave control, it is possible to increase the frequency when the frequency is made variable. Power accuracy.

The pass-through type power sensor 37 is attached to the front end of the coaxial cable constituting the transmission line 33 even when the frequency is not changed, and therefore, by feeding back the detection signal to the high-frequency power generator 32, The loss due to the transmission line 33 can be corrected, and the power value can be controlled to be closer to the power value used in the actual program. Further, the frequency range of the pass-through power sensor 37 is appropriately selected, and the fundamental frequency (the changed frequency in the case where the frequency is changed) is set within the range of the pass-through power sensor 37 and will be high. The harmonic frequency is set outside the frequency range, thereby improving accuracy.

In addition, in the case where the amount of change from the frequency of the high-frequency power generator 32 is not too large, even in the case where the detection signal of the pass-through power sensor 37 is fed back to the impedance matcher 34, the impedance matcher 34 can be realized. High precision tuning in the middle.

<Second embodiment>

Next, a second embodiment will be described. Fig. 6 is a schematic view showing a substrate processing apparatus according to a second embodiment of the present invention. The substrate processing apparatus 200 of the present embodiment is basically applied to the substrate processing of the first embodiment. The apparatus 100 is a device (bulk type device) that performs plasma processing of a plurality of substrates. Therefore, in FIG. 6, the same symbols as those in FIG. 1 are denoted by the same reference numerals and will be described.

The substrate processing apparatus 200 is configured as a parallel plate type plasma processing apparatus that performs plasma processing on a plurality of substrates, and accommodates a plurality of (three sheets in FIG. 6) substrates S and has a chamber 1 for performing plasma processing. . The chamber 1 is the same as that of the first embodiment, and is grounded.

In the chamber 1, a plurality of pairs (three pairs in FIG. 6) of parallel plate electrodes are disposed in the vertical direction, and the parallel plate electrodes are arranged such that the cathode electrodes 3 and the anode electrodes 4 face each other in the vertical direction. The anode electrode 4 is configured as a lower electrode, and functions as a mounting table of the substrate S in the same manner as the substrate processing apparatus 100, and the heater 14 is buried and grounded. The cathode electrode 3 is configured as an upper electrode and functions as a plasma generating electrode to which high-frequency power is supplied. However, unlike the first embodiment, the cathode electrode 3 does not have a function as a head.

The cathode electrode 3 and the anode electrode 4 are supported by the chamber 1 by the support member 52. Further, by providing the elevating mechanism and raising and lowering the cathode electrode 3 or the anode electrode 4, it is possible to adjust the distance between the cathode electrode 3 and the anode electrode 4.

In the present embodiment, the processing gas supply unit 5 includes the processing gas supply unit 15 and the processing gas supply path 16, but the processing gas supply path 16 is connected to the gas introduction port 10 ' provided on the top wall of the chamber 1. And do not use the nozzle. Of course, as in the first embodiment, each of the cathode electrodes 3 can function as a head, and the processing gas can be introduced into the cathode electrode in a sprayed manner.

The exhaust unit 6 has a basic configuration similar to that of the first embodiment, and includes an exhaust pipe 17, an exhaust device 18, and an automatic pressure control valve (APC) 19. However, the exhaust pipe 17 is not connected to the bottom of the chamber 1, but It is connected to the upper and lower parts of the side wall.

A transfer port (not shown) that can transport a plurality of substrates at a time is provided in the side wall of the chamber 1, and the transfer port can be opened and closed by a gate valve (not shown).

The substrate processing apparatus 200 of the present embodiment has the same plasma generating apparatus 2 as that of the first embodiment. That is, even in the present embodiment, the plasma generating device 2 has: an external oscillator 31; a high frequency power generator 32; a transmission line 33; an impedance matching unit 34; a directional coupler 35; a spectrum analyzer 36; The pass type power sensor 37 is provided at the upstream side of the impedance matching unit 34 of the transmission line 33; the power meter 38 measures the signal from the pass type power sensor 37 and feeds it back to the high frequency generator 32. The transmission line 33 is branched at the front end of the impedance matching unit 34 as a transmission line 51, and the branched transmission line 51 is connected to the center of the upper surface of each cathode electrode 3.

In the substrate processing apparatus 200 of the present embodiment, the control unit (computer) 7 having the same configuration as that of the first embodiment is provided, and the control unit 7 controls the respective components.

In the substrate processing apparatus 200 of this configuration, plasma processing such as plasma CVD processing is performed in the same manner as the substrate processing apparatus 100 of the first embodiment. That is, a plurality of (three) substrates S are placed on the respective anode electrodes 4, and the inside of the chamber 1 is evacuated to make a predetermined vacuum environment in the chamber, and the substrate S is heated by the heater 14 to At a predetermined temperature, the processing gas is introduced into the chamber 1 from the processing gas supply unit 15 via the processing gas supply path 16 and the gas introduction port 10 ' , and high-frequency power is supplied from the high-frequency power generator 32 to the respective cathode electrodes. 3.

Thereby, a high-frequency electric field is generated between the cathode electrode 3 and the anode electrode 4 opposed to each of the parallel plate electrodes, and is heated by the heater 14 by the plasma of the processing gas generated by the high-frequency electric field. A predetermined plasma treatment such as plasma CVD is performed on the substrate S.

Even in the present embodiment, the reflected wave via the impedance matching unit 34 is guided to the spectrum analyzer 36 by the directional coupler 35, and the spectrum of the reflected wave is taken out, and only the reflection component of the fundamental frequency can be fed back to the impedance. The matcher 34, therefore, in the impedance matcher 34, enables high-precision tuning.

Further, by providing the pass-through power sensor 37, the signal detected at the place is fed back to the high-frequency power generator 32 via the power meter 38, and this can be used for power control and reflected wave control, and can be improved. The power accuracy when the frequency is set to be variable.

<Modifications, etc.>

Further, the present invention is not limited to the above embodiment, and various modifications can be made. For example, in the above embodiment, the transmission type power sensor 37 is disposed closer to the high frequency power generator 32 than the directional coupler 35 in the transmission line 33, and these positions may be reversed.

Further, in the above embodiment, the spectrum analyzer 36 is used. As a detector for obtaining a spectrum of a reflected wave signal including high harmonics, the frequency spectrum is not limited thereto. Further, although the FFT method is preferred as the detector, the present invention is not limited thereto, and may be a super-heterodyne method or the like.

Further, although plasma CVD is used as the plasma treatment in the substrate processing apparatus, the principle of the present invention is of course not limited thereto, and can be applied to other plasma processing such as plasma etching. Further, in the above embodiment, the high-frequency power is introduced to the upper electrode of the parallel plate electrode and the lower electrode is grounded. However, the upper electrode may be grounded and high-frequency power may be introduced to the lower electrode, and high-frequency power may be introduced. To both the upper electrode and the lower electrode. Further, in the case where the present invention is applied to a batch type apparatus, the number of substrates to be processed at one time is not limited to three. Further, the substrate to which the present invention is applied is not particularly limited, and can be applied to various substrates such as a solar substrate or a glass substrate for a flat panel display (FPD).

1‧‧‧ chamber

2‧‧‧ Plasma generating device

3‧‧‧Cathode electrode

3a‧‧‧ gas diffusion space

3b‧‧‧ gas discharge hole

4‧‧‧Anode electrode

5‧‧‧Process Gas Supply Department

6‧‧‧Exhaust Department

7‧‧‧Control Department

10‧‧‧ sprinkler

12‧‧‧Insulating components

13‧‧‧Insulating components

14‧‧‧heater

15‧‧‧Processing gas supply mechanism

16‧‧‧Processing gas supply path

17‧‧‧Exhaust piping

18‧‧‧Exhaust device

19‧‧‧Automatic pressure control valve

20‧‧‧ moving into and out

21‧‧‧ gate valve

31‧‧‧External Oscillator

32‧‧‧High frequency power generator

32a‧‧‧Low-pass filter

33‧‧‧Transmission line

34‧‧‧impedance matcher

35‧‧‧ Directional Coupler

36‧‧‧Spectrum Analyzer

37‧‧‧ Pass-through power sensor

38‧‧‧Power meter

100‧‧‧Substrate processing unit

S‧‧‧Substrate

Claims (6)

A plasma generating device generates plasma by supplying high-frequency power to a plasma generating electrode, and is characterized in that: a high-frequency oscillator is provided to change a frequency at which a high frequency is oscillated; and a high-frequency power generator is amplified by a high frequency of the frequency at which the high frequency oscillator oscillates generates high frequency power; a transmission line transmits high frequency power from the high frequency power generator to the plasma generating electrode; and an impedance matching device is provided in the transmission line And matching the generated plasma load impedance with the impedance of the transmission line on the high frequency power generator side; the directional coupler is disposed between the high frequency power generator of the transmission line and the impedance matching device And a detector that detects a spectrum of the guided reflected wave via the directional coupler and feeds back a reflected component of the fundamental frequency to the impedance matcher. The plasma generating device of claim 1, further comprising: a pass-through power sensor disposed between the high-frequency power generator of the transmission line and the impedance matching device; and a power meter, the measurement is from The signal of the pass-through power sensor is fed back to the aforementioned high frequency generator. The plasma generating apparatus of claim 1, wherein the detector is a spectrum analyzer. The plasma generating apparatus of claim 1, wherein the detector has a Fourier transform function of converting an input signal into a digital signal and performing fast Fourier transform to obtain a frequency spectrum. A substrate processing apparatus for processing a substrate by a plasma of a processing gas generated by high-frequency power, characterized in that: a chamber is provided, and the substrate is housed and held under vacuum; and a plasma generating electrode is disposed in the chamber a high frequency electric power is supplied to generate plasma; a plasma generating device supplies high frequency electric power to the plasma generating electrode to generate plasma; and a processing gas supply means supplies a processing gas to the chamber, the plasma generating device A high-frequency oscillator that changes a frequency of a high frequency that oscillates; a high-frequency power generator that amplifies a high frequency of a frequency oscillated by the high-frequency oscillator to generate high-frequency power; and a transmission line from the foregoing The high frequency power generator transmits the high frequency power to the plasma generating electrode; the impedance matching device is disposed on the transmitting line to cause the generated plasma load impedance to be the impedance of the transmitting line on the high frequency power generator side a directional coupler disposed between the high frequency power generator of the foregoing transmission line and the impedance matching device; the detector passes through the foregoing direction Spectrum of the reflected wave guide coupler detector, and wherein the reflection component is fed back to the fundamental frequency of the impedance Matcher. The substrate processing apparatus according to claim 5, wherein a plurality of plasma generating electrodes are provided corresponding to the plurality of substrates, and the high frequency electric power is generated by supplying the high frequency electric power to the respective plasma generating electrodes from the plasma generating device. Plasma to process a plurality of substrates.