JPH10335095A - Microwave applying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device, which can set a load impedance at a reference impedance with the microwave of a really operated magnetron, by providing a means for adjusting the impedance of a main circuit so as to coincide with the impedance set in an auxiliary circuit. SOLUTION: Even in the case where the oscillating microwave frequency of a magnetron 1, which is replaced new, is changed, the microwave flowing in an auxiliary circuit system is similarly changed, and since an impedance adjusting unit 16 is already set at the reference impedance, output of an impedance detecting unit 15 corresponding to the reference impedance, which reflects the changed frequency, is obtained. Namely, a necessity of measuring the frequency of the microwave generated from the magnetron 1 so as to correct the frequency is eliminated. Impedance can be set at the original reference impedance by adjusting an impedance adjusting unit 7 so that the output of the impedance detecting unit 12 and the output of the impedance detecting unit 15 coincide with each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a microwave application device, and more particularly to a microwave plasma etching device used as a semiconductor manufacturing device.

[0002]

2. Description of the Related Art In a conventional impedance adjuster of a microwave application device, an impedance adjuster and an impedance detector are arranged in a main circuit, and a load impedance is matched (reflection state) while monitoring a detection voltage / current of the detector. The impedance adjuster was driven to adjust the impedance so that the value became zero.

[0003] The setting of the matching state is achieved by setting the detection signal of the detector to a constant value irrespective of the detection location, so that it can be relatively easily performed.

[0004] However, a method of relatively simply setting an impedance of a certain value other than matching has not been proposed so far.

[0005] The impedance is determined only when both the standing wave ratio (reflection coefficient) and the phase are clear. However, while the standing wave ratio can be detected relatively easily, it is difficult to detect the phase. is there.

For this reason, a method for keeping only the standing wave ratio constant (ie, monitoring the traveling wave power and the reflected wave power,
The method of adjusting each of them to a certain value) is adopted in a semiconductor manufacturing apparatus such as a microwave plasma etching apparatus.

However, in this method, since the phase condition is ignored, the impedance cannot be made constant.
For example, if the material of the etching gas is changed or the magnetron which is a microwave tube is replaced, the performance or yield of the product will be adversely affected.

If the microwave frequency is constant and known, it is possible to set a constant impedance other than matching by devising the detection part.

However, the magnetron has the property that the oscillation frequency is different when the operating current condition and the load impedance condition are different even in the same solid, and the matching frequency is also different depending on the solid, so that when measuring the impedance, the frequency is measured. Must be done, which can be very large and expensive.

An example of a conventional automatic impedance adjuster is:
For example, as described in page 6 of the microwave heating device catalog (CATALOG Vol.2) of Japan High Frequency Co., Ltd., a matching device (impedance adjuster) and a signal detector are arranged in the circuit from the load side. A technique that sends the result calculated by the operation unit to the servomotor in the matching unit so that the detection signals of up to five detection units have the same value and moves the impedance adjustment unit of the matching unit. There is.

In this case, the system is set so that the load impedance is matched (that is, there is no reflected wave).

According to a microwave automatic matching device (Cat No. LZ-L3-0167) manufactured by Daihen Co., Ltd., the result calculated by the controller unit so that the detection signals of the three detection units have the same value. Is sent to the servo motor in the matching unit, and the technique for moving the impedance adjusting unit of the matching unit to match the load impedance is described.

Also, from the block diagram in the description of the automatic matching device on page 6 of the catalog (CATALOGVol.2) of the microwave heating device of the Japan High Frequency Corporation, the method for keeping only the standing wave ratio constant (ie, The method of monitoring the traveling wave power and the reflected wave power and adjusting each to have a certain value) can be realized by releasing the automatic control unit and manually adjusting the matching device. There is an explanation to ask. A conventional example will be described with reference to FIG. 2 with reference to this block diagram.

FIG. 1 shows a microwave plasma etching apparatus (semiconductor manufacturing apparatus) to which a microwave plasma generator is applied.

1 is a magnetron, 1a is a magnetron antenna, and radiates microwaves oscillated by the magnetron. Numeral 2 is a high-frequency coupler, which ensures that microwaves radiated from the magnetron antenna are efficiently transmitted to the waveguide circuit system and does not leak to parts other than the waveguide circuit system. Reference numeral 3 denotes an isolator, which transmits microwaves radiated from the magnetron antenna, that is, traveling waves without attenuation, reflected from the load side opposite to the magnetron, and returns to the magnetron side, ie, reflected waves. Has a large damping function. 4 is a connecting waveguide for adjusting the length of the waveguide circuit. Reference numeral 5 denotes a power monitor for detecting the power of the traveling wave and the reflected wave propagating through the waveguide. 6 is a connecting waveguide for adjusting the length of the waveguide circuit. 7 is an impedance adjuster. Reference numeral 9 denotes a load portion, which includes a portion for converting the etching gas into plasma by microwaves, that is, an applicator (not shown). 8 is a connecting waveguide.

In the conventional example of the above configuration shown in FIG. 2, the state of the load section is estimated by a power monitor. In other words, the optimum condition is set for the plasma state based on the wafer etching state obtained in advance and the relationship between the anode current value of the magnetron, the traveling wave power, and the reflected wave power. Are adjusted by the impedance adjuster 7 so as to satisfy the following relationship.

However, in the above-described adjusting method, for example, the impedance is uniquely determined under the condition that there is no reflected wave power (that is, the matching condition). Therefore, even if the traveling wave power and the reflected wave power are set to constant values, the impedance is not determined because this is merely a condition setting for keeping the standing wave ratio constant. It was a bad device.

[0018]

In an apparatus utilizing plasma generated by exciting a gas or the like by a microwave oscillated by a magnetron (for example, a semiconductor manufacturing apparatus for etching or ashing a semiconductor wafer), a magnetron is used. Is treated as a consumable item, and the magnetron is usually replaced with a new one before the end of its life.
This is because when the magnetron reaches the end of its life, the entire wafer to be processed becomes defective.

Although magnetrons are produced in modern mass production plants, their microwave performances vary from individual to individual and are not exactly the same, and so-called microwaves such as frequency, sink phase, output coupling degree, etc. Performance is slightly different. Further, even with one magnetron, the microwave output and frequency greatly change due to the load impedance. Even if the anode current is changed, the microwave output and the frequency also change greatly. Magnetron manufacturers publish the changes in frequency and microwave output due to load impedance as a Leake diagram (Leake diagram) and the change in microwave output and frequency with respect to anode current as performance charts in catalogs, specifications, technical documents, etc. doing. Further, the magnetron has a phenomenon called pushing, and even if the average current value and the load impedance are the same, when the peak current changes, the oscillation frequency also changes according to the change.

Therefore, in the plasma application apparatus, an isolator is inserted next to the magnetron to absorb only the reflected wave from the load, thereby making the load impedance of the magnetron as close as possible to the matching state.

However, even in this case, as described above, the oscillation frequency under the matching load condition of the magnetron varies depending on the individual. When the frequency changes, the length of the wavelength also changes, so the standing wave distribution of the microwave from the magnetron (or isolator) to the applicator also changes. That is, even if the load impedance is the same, the frequency is different, so that the detection voltage value / current value of the impedance detection unit does not indicate the same value. Of course, there is no problem if a method of detecting and correcting the frequency is used, but the detection circuit becomes very expensive.

At first glance, it may be considered that the impedance can be measured by using a network analyzer. However, the network analyzer is a method of measuring the impedance using a stable, continuous, constant-frequency microwave oscillator. , Modern analyzers digitize signal processing to increase accuracy,
It cannot cope with the condition where the oscillation frequency changes in a complicated manner like a magnetron, and cannot measure the actual operating impedance (impedance using the oscillation frequency of the magnetron). Of course, if a new impedance measuring device using the oscillation frequency of the magnetron is newly designed, the measurement of the load impedance is not impossible, but becomes very expensive.

On the other hand, in a plasma application apparatus, not only one kind of plasma gas but various kinds of gases are used. Since the plasma generation state differs depending on the type of this gas, a container (applicator) in which the plasma exists
The density and location of the plasma in the room change. As a result, the load impedance as seen from the waveguide by the applicator changes.

However, based on past experience, in the case of plasma-applied equipment having the same specifications, if the load impedance viewed from the waveguide is set within a certain range, the product will be good even if the type of gas changes. I understand that.
However, it is said that the optimum load impedance point is different when the specifications of the plasma application device are different.

Therefore, in the conventional microwave application apparatus, each time the magnetron is replaced and the operating current of the magnetron is changed, the setting conditions of the apparatus are optimized while actually recognizing the product yield. I had to do it.

The present invention has been made in view of such circumstances, and has as its object to set a load impedance to a reference impedance (a load impedance to be set) using microwaves of a magnetron actually operating. It is to provide a microwave application device that can be used.

[0027]

SUMMARY OF THE INVENTION Among the inventions disclosed in the present application, the outline of a representative one will be briefly described.
It is as follows.

That is, a sub-circuit is provided via a directional coupler to a main circuit including a detector for detecting a load impedance and an adjuster for adjusting the load impedance, and the sub-circuit is a sub-circuit of the main circuit. An adjuster for setting the non-reflection terminator on the side where the reflected wave from the load flows, and a desired impedance on the side where the traveling wave of the main circuit flows, a non-reflection terminator and a detector for confirming and detecting the impedance A microwave application device, characterized by comprising means for adjusting the impedance of the main circuit so as to match the impedance set in the sub-circuit.

The microwave application device thus configured is configured so that the microwave of the magnetron flows also in its sub-circuit, and the impedance adjuster in this sub-circuit causes the load impedance to be changed to the reference impedance (the load impedance to be set). Is set, and the distribution of the standing wave of the microwave oscillated by the magnetron when the reference impedance is set by the detector in the sub-circuit can be known.

Therefore, the load impedance of the main circuit is adjusted to the reference impedance by adjusting the impedance adjuster of the main circuit so that the output of the detector of the main circuit exhibits the same standing wave distribution as the detector of the sub-circuit. It can be set equally.

From this, when the microwave application device is, for example, a microwave plasma etching device,
Even if the etching gas or the like is changed, a uniform plasma with the highest etching performance can be generated, and as a result, an inexpensive device with a high yield can be obtained.

[0032]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the microwave application apparatus according to the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing a microwave plasma generator.

In FIG. 1, first, there is a magnetron 1, and a microwave is radiated from an antenna 1a provided therein.

Reference numeral 2 denotes a high-frequency coupler, which is configured so that microwaves radiated from the magnetron 1 can efficiently propagate to the waveguide circuit system without leakage.

Reference numeral 3 denotes an isolator which transmits microwaves (traveling waves) radiated from the magnetron 1 without being attenuated to the load side, and reflects the microwaves (reflected waves) reflected from the load side and returned to the magnetron 1 side. ) Is greatly attenuated.

Reference numeral 10 denotes a connecting waveguide, which is configured so that the length of the waveguide circuit can be adjusted.

Reference numeral 11 denotes a directional coupler, which is configured to guide the traveling wave and the reflected wave propagating in the main circuit to the sub-circuit at a predetermined degree of coupling (degree of coupling of P (dB)).

That is, the traveling wave and the reflected wave in the sub-circuit have outputs that are attenuated by P (dB) with respect to those in the main circuit.

The reflected wave in the sub-circuit is absorbed by the non-reflection terminator 13 so as not to be reflected. On the other hand, the traveling wave in the sub-circuit is connected to the connecting waveguide 14 and the impedance detector 1.
5, through the impedance adjuster 17, the non-reflection terminator 1
7 so that the light is not absorbed and reflected by the non-reflection terminator 17.

A part of the microwave reflected by the impedance adjuster 16 is coupled to the main circuit via the directional coupler 11. In this case, P (d
B) It attenuates and propagates to the main circuit. However, the effect of this component is so small that the traveling wave flowing through the main circuit is extremely small and can be ignored.

A power monitor 5 is connected to the main circuit of the directional coupler 11 and is configured to detect the power of the traveling wave and the reflected wave propagating through the main circuit.

Reference numeral 12 denotes an impedance detector, 7 denotes an impedance adjuster, 8 denotes a connecting waveguide, and 9 denotes a load.

Here, the load 9 is configured as a device including an applicator for converting, for example, an etching gas into plasma by microwaves.

Hereinafter, the operation of the microwave application apparatus according to the present invention will be described in comparison with a microwave application apparatus to which the present invention has not been applied and other conditions are completely the same (FIG. 2).

The waveguide of the impedance detector 12 shown in FIG. 1 and the waveguide of the connecting waveguide 6 shown in FIG. 2 have the same specifications including the length, and the impedance adjuster 7 common to FIG. 1 and FIG. The connecting waveguide 8 and the load section 9 have the same specifications. Further, the cross-sectional dimensions of the waveguide used in the microwave circuit system used in FIGS. 1 and 2 are the same.

Here, as shown in FIGS. 1 and 2, point B is a connection point on the load side of the impedance adjuster 7, and point C is a connection point on the load side of the isolator. Point A in FIG. 1 indicates a connection point on the magnetron side of the impedance detector 12,
Point A in FIG. 2 is a connection point on the magnetron side of the connecting waveguide 6.

Further, the distance from point B to point C in FIG. 1 is n, and the distance from point B to point C in FIG. 2 is m.

In such a configuration, the configuration from point A to the load in FIG. 1 and the configuration from point A to the load in FIG. 2 have the same specifications.

Further, the distance n in FIG. 1 is the same as the distance m in FIG. On the other hand, the impedance adjuster 16 and the impedance detector 1 used in the sub-circuit system of FIG.
5 has the same specifications as the impedance adjuster 7 and the impedance detector 12 of the main circuit system, respectively. A connection point of the impedance detector 15 of the sub-circuit system on the directional coupler 11 side is defined as a point D.

With the above configuration, the apparatus shown in FIG. 1 and the apparatus shown in FIG. 2 have exactly the same functions as far as the main circuit is concerned.

Here, the impedance detectors 12 and 15 are of a type for obtaining a standing wave of a micro wave propagating in a waveguide, for example. Specifically, for example, a certain number of intervals are set in the center of the E-plane of the waveguide in a range of about 3/4 of the guide wavelength of the microwave in the direction of the waveguide axis. At a point, the microwave voltage in the waveguide is measured. To measure the microwave voltage, for example, a small antenna of the electric field coupling type couples with the microwave in the waveguide, rectifies it with a diode, and
Find the voltage. Since the voltage standing wave is obtained from the position of the minute antenna and the detected voltage, the impedance when the load is viewed from the reference plane A point or the reference plane D point can be calculated.

Here, when the apparatus is newly introduced, the impedance adjuster 7 is adjusted so that the etching performance of the wafer in the applicator (not shown) of the load section 9 is optimized. In the apparatus of this embodiment, the best operating point as a result of the adjustment is obtained in the form of a voltage standing wave waveform as the output of the impedance detector 12, whereby the voltage standing wave ratio and the voltage standing wave from the reference point A are obtained. The impedance is determined from the wave number up to the minimum value of the standing wave.

Then, the impedance adjuster 16 is adjusted so that the same voltage standing wave ratio as the voltage standing waveform of the output of the impedance detector 12 and the wave number up to the minimum value of the standing wave can be obtained from the impedance detector 15. .

With this adjustment, the impedance when viewing the impedance adjuster 16 from the point D is the same as the impedance when viewing the load section 9 from the point A. This impedance is called a reference impedance.

Thereafter, when the etching gas is changed,
As a result, the distribution of the plasma changes, so that the impedance when the load section 9 is viewed from the point B changes. Therefore, the impedance when the load section 9 is viewed from the point A also changes.

When the change in impedance is small, the microwave frequency oscillated by the magnetron 1 does not change due to the function of the isolator 3. However, when the change in impedance is large (especially when the voltage standing wave changes greatly), depending on the specifications of the isolator 3,
The oscillation frequency of the magnetron 1 changes so that the change in impedance cannot be ignored.

When the frequency hardly changes, by adjusting the impedance adjuster 7 so that the output of the impedance detector 12 matches the voltage standing waveform of the output of the impedance detector 15, the load from the point A is adjusted. The impedance looking at the part can be set to the initial impedance.

Here, even if the output of the impedance detector 12 does not need to be matched with the output of the impedance detector 15, the output of the impedance detector 12 at the time of the initial reference impedance is stored, and such an output is stored. It may be considered that the impedance adjuster 7 should be adjusted so as to be as follows.

However, the problem here is that the oscillation frequency of the magnetron 1 changes. This is because when the above-mentioned change in impedance is so large that the movement of the isolator 3 cannot be ignored, the Can occur when the magnetron is replaced and when the magnetron anode current is changed.

As described above, when the oscillation frequency of the magnetron changes, the wavelength propagating in the waveguide (so-called guide wavelength) also changes, so that the waveform of the voltage standing wave also changes. Therefore, the stored impedance detector 1
The output of the impedance adjuster 7 cannot be matched so that the output becomes 2.

In this case, the frequency of the microwave is measured, and the output of the stored impedance detector, that is, the waveform of the voltage standing wave is corrected by the guide wavelength, and the output of the impedance detector 12 is made equal to the corrected waveform. Thus, if the impedance adjuster 7 is adjusted, the impedance can be matched with the reference impedance. However, there is a disadvantage that the entire system becomes large and expensive due to frequency detection, output waveform correction, and the like.

On the other hand, in the present embodiment, for example, even if the oscillating micro frequency of the newly exchanged magnetron 1 changes, the microwave flowing in the sub-circuit system also changes. Since the impedance adjuster 16 has already been set to the reference impedance,
The output of the impedance detector 15 is an output corresponding to the reference impedance reflecting the changed frequency.

From this, the impedance detector 12
The impedance adjuster 7 can be adjusted so that the output of the impedance detector 15 matches the voltage standing wave ratio of the impedance detector 15 and the wave number up to the minimum standing wave, and can be set to the initial reference impedance. .

Such adjustment can be automated as shown in the block diagram of FIG. In FIG. 3, a particularly characteristic configuration is a comparing means for comparing the output from the detector for detecting the load impedance of the main circuit with the output from the detector for confirming and detecting the impedance of the sub-circuit, Means is provided for driving a regulator for adjusting the load impedance so that the output of the detector for detecting the load impedance is equal to the output from the detector for confirming and detecting the impedance of the sub-circuit.

Such an operation is referred to as a conventional operation (see FIG. 4).
This will be described in comparison with.

First, in the prior art, (1) at the stage where a semiconductor manufacturing apparatus (microwave plasma etching apparatus) is installed and adjusted at a semiconductor manufacturing maker, an impedance adjuster is adjusted by performing an actual experiment while adjusting an optimum value. Adjust to impedance.

(2) The output of each antenna jig of the impedance detector at this time is stored. Here, the antenna jig is to project the antenna (probe) into the waveguide,
A jig for detecting and rectifying a microwave voltage generated by a potential difference between the tip and the wall of the waveguide by a diode.

(3) Therefore, even if the composition of the etching gas is changed, the impedance adjuster may be adjusted so that the stored output of each antenna jig is obtained.

(4) In this case, however, there is an isolator between the magnetron and the impedance detector, and only when the operating current value of the magnetron is not changed even if the component of the etching gas is changed (that is, the microwave output is (No change).

(5) That is, in practice, in order to obtain optimum etching conditions, it is usually necessary to change the components of the etching gas and also the operating current value of the magnetron.

(6) The operating current value of the magnetron is changed or the specifications of the anode power supply of the magnetron are changed (especially, when the ripple rate is different, the peak anode current value changes).
If so, the oscillation frequency of the magnetron changes.

Of course, even under the same operating conditions, if the magnetron is replaced, the oscillation frequency changes due to the individual difference of the magnetron.

(7) When the oscillation frequency changes, the wavelength changes. Therefore, no matter how the impedance adjuster is adjusted to obtain the stored output of each antenna jig, there is no match. When the number of antenna jigs is small, they may coincide with each other, but the impedance is no longer the same as the initial one.

(8) As described above, conventionally, when trying to match the impedance, the oscillation frequency is measured, and
A change in frequency (change in wavelength) is corrected for the output of the impedance detector, and the impedance adjuster is adjusted by comparing the output with the stored impedance.

On the other hand, in this embodiment, (9) the impedance is adjusted to the optimum position as in the above (1).

(10) At the same time, the impedance adjuster is adjusted and fixed so that the impedance of the sub-circuit becomes the same as that of the main circuit.

In this case, as a product of the semiconductor manufacturing apparatus (microwave plasma etching apparatus), when the optimum impedance is known, the impedance adjuster of the sub-circuit may be a fixed impedance element.

(11) Even if the oscillation frequency changes, the reference impedance does not change, so that the output of the impedance detector of the sub-circuit and the output of the impedance detector of the main circuit become the same. Is adjusted, the impedance adjusted in (9) can be set.

According to this embodiment, the impedance when the load 9 is viewed from the point A can always be set to the reference impedance, so that the inexpensive microwave plasma etching with uniform etching performance, high yield, and high yield can be achieved. The device can be obtained.

It is to be noted that, by configuring the portion between B and C in FIG. 1 by itself and replacing it with the portion between B and C in FIG. 2, the existing device can be added high value. It is also possible to commercialize the portion between them as an impedance adjuster.

The reference point A is the impedance adjuster 7
In principle, the point may be at a point C from the connection point on the side of the magnetron 1; therefore, the point C may be used in principle. However, when the frequency changes, the voltage standing wave changes (by changing the wavelength, Considering the change of the position of the standing wave minimum point), it is better to set the impedance adjuster 7 at or near the connection point on the magnetron 1 side. Further, the impedance adjuster can be downsized. This is because the isolator 3 absorbs the reflected waves from the load section 9 and the impedance adjuster 7, so that the distance from the connection point on the magnetron side of the impedance detector 12 to the point C can be arbitrarily selected. That is, needless to say, it is not necessary to stick to m = n.

If the impedance detectors 12 and 15 have exactly the same specifications, the output of the impedance detector 15 of the sub-circuit system is set to P (d
By amplifying only B), the output can be made the same value as the output of the impedance detector 12 of the main circuit. Therefore, the servo motor is driven to adjust the impedance adjuster 7 so that both outputs have the same value. If this method is adopted, the automation will be very simple.

Further, as described above, in the case of the microwave plasma application device, the impedance showing the best performance of the device has almost the same value in the device having the same specification. The structure of the portion to be formed does not need to be a structure having an adjusting function like the impedance adjuster 16, and it is needless to say that a structure having a fixed impedance equal to the reference value can be obtained. It is important that the reference point D in FIG.
Is the same as the reference point A, that is, the distance from the impedance detection unit to the impedance addition unit is made equal (h = k in FIG. 1).

Although the specification of the impedance detector has been described in the form of outputting the standing wave waveform to obtain the impedance, if the configuration for obtaining the impedance is adopted,
It goes without saying that any configuration may be used.

As described above, according to the above-described embodiment, for example, even if the microwave frequency oscillated by the newly replaced magnetron 1 changes, the microwave flowing through the sub-circuit system also changes. Since the impedance adjuster 16 has already been set to the reference impedance, the output of the impedance detector 15 becomes an output corresponding to the reference impedance reflecting the changed frequency. That is, there is no need to measure the frequency of the microwave oscillated by the magnetron and perform frequency correction. The initial reference impedance can be set by adjusting the impedance adjuster 7 so that the output of the impedance detector 12 matches the output of the impedance detector 15.

Therefore, according to the present invention, the impedance when the load 9 is viewed from the point A can always be set to the reference impedance, so that even if the etching gas is changed, the uniform plasma that maximizes the etching performance can be obtained. Can be generated, and as a result, an inexpensive microwave plasma etching apparatus with a high yield can be obtained.

[0088]

As described above, according to the microwave application apparatus of the present invention, the load impedance can be set to the reference impedance (the load impedance to be set) by using the microwave of the magnetron actually operating. become.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an embodiment of a microwave application device according to the present invention.

FIG. 2 is a configuration diagram illustrating an example of a conventional microwave application device.

FIG. 3 is a block diagram showing one embodiment of the operation of the microwave application device according to the present invention.

FIG. 4 is a configuration diagram showing an example of the operation of a conventional microwave application device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Magnetron, 2 ... High frequency coupler, 3 ... Isolator, 4, 6, 8, 10, 14 ... Connecting waveguide, 5 ... Power monitor, 7, 16 ... Impedance adjuster, 9 ... Load part, 11 ... Direction Sex couplers, 12, 15: Impedance detector, 13, 17: Non-reflection terminator.

Claims (2)

[Claims] 1. A sub-circuit is provided via a directional coupler to a main circuit including a detector for detecting load impedance and an adjuster for adjusting the load impedance, wherein the sub-circuit is a main circuit. An adjuster for setting the non-reflection terminator on the side where the reflected wave from the load flows, and a desired impedance on the side where the traveling wave of the main circuit flows, a non-reflection terminator and a detector for confirming and detecting the impedance A microwave application device comprising means for adjusting the impedance of the main circuit so as to match the impedance set in the sub-circuit. 2. A comparing means for comparing an output from a detector for detecting the load impedance of the main circuit with an output from a detector for confirming and detecting the impedance of the sub-circuit, and a detecting means for detecting the load impedance of the main circuit. 2. A micro-controller according to claim 1, further comprising means for driving an adjuster for adjusting a load impedance such that an output of the detector is equal to an output from a detector for confirming and detecting the impedance of the sub-circuit. Wave application equipment.