JPH11251094A - Plasma processing device and impedance measuring tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a membrane having a small susceptor impedance, low frequency dependency, high power consumption efficiency, a high forming speed and good quality by alternatingly short-circuiting a chamber wall and an electrode having the same DC potential as that of a chamber. SOLUTION: A chamber wall 10 and the susceptor shield 12 of an electrode having the same DC potential as that of a chamber are alternatingly short- circuited by metal plates 80a, 80b. The chamber wall 10 and the shield 12 are alternatingly short-circuited at two positions. For this short-circuit, one-end sections of the metal plates 80a, 80b made of an elastic spring body are connected to the bottom section 10b of the chamber wall 10 at short-circuit points B1, B2, and the other ends are connected to the shield 12 at short-circuit points A1, A2. The short-circuit points B1, B2 are arranged near the outermost periphery of the shield 12, and the distances to the side wall 10s of the chamber wall 10 are minimized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma processing apparatus.

[0002]

2. Description of the Related Art FIG.
The following are known.

A conventional plasma processing apparatus includes a high-frequency power source 1
A matching circuit is interposed between the electrode and the plasma excitation electrode 4. The matching circuit is a circuit for obtaining impedance matching between the high-frequency power supply 1 and the plasma excitation electrode 4.

The high frequency power from the high frequency power supply 1 is supplied to the plasma excitation electrode 4 by the power supply plate 3 through the matching circuit.

The matching circuit and the power supply plate 3 are housed in a matching box 2 formed by a housing 21 made of a conductor.

A shower plate 5 having a large number of holes 7 formed under a plasma excitation electrode (cathode electrode) 4
Are provided, and a space 6 is formed by the plasma excitation electrode 4 and the shower plate 5. The space 6 is provided with a gas introduction pipe 17. The gas introduced from the gas introduction pipe 17 is supplied into the chamber 60 formed by the chamber wall 10 through the hole 7 of the shower plate 5. Reference numeral 9 denotes an insulator that insulates the chamber wall 10 from the plasma excitation electrode (cathode electrode) 4. Also,
Illustration of the exhaust system is omitted.

On the other hand, a wafer susceptor (susceptor electrode) 8 on which the substrate 16 is mounted and also serves as a plasma excitation electrode is provided in the chamber 60, and a susceptor shield 12 is provided around the wafer susceptor. The wafer susceptor 8 and the susceptor shield 12 can be moved up and down by the bellows 11 so that the distance between the plasma excitation electrodes 4 and 8 can be adjusted.

A second high frequency power supply 15 is connected to the wafer susceptor 8 via a matching circuit housed in a matching box 14. The chamber and the susceptor shield 12 have the same DC potential.

FIG. 14 shows another conventional plasma processing apparatus. The plasma processing apparatus shown in FIG. 12 is a so-called two-frequency excitation type plasma processing apparatus, whereas the plasma processing apparatus shown in FIG. 14 is a one-frequency excitation type plasma processing apparatus. That is, high-frequency power is supplied only to the cathode electrode 4, and the susceptor electrode 8 is grounded. High frequency power supply 15 and matching box 1 shown in FIG.
There is no 4. The susceptor electrode 8 and the chamber wall 10 have the same DC potential.

FIG. 15 shows another conventional plasma processing apparatus. In the plasma processing apparatus shown in FIG. 15, a shower plate is not used, and the cathode electrode 4 which is a plasma excitation electrode and the wafer susceptor 8 are directly opposed. A shield 20 is provided around the back surface of the cathode electrode 4. The other points have the same configuration as the plasma processing apparatus shown in FIG.

FIG. 16 shows another conventional plasma processing apparatus. The plasma processing apparatus shown in FIG. 15 is a so-called dual frequency excitation type plasma processing apparatus.
Is a single frequency excitation type plasma processing apparatus. That is, high-frequency power is supplied only to the cathode electrode 4, and the susceptor electrode 8 is grounded. There is no high frequency power supply 15 and matching box 14 shown in FIG. Also, the susceptor electrode 8 and the chamber wall 1
0 has the same DC potential.

However, when the conventional plasma processing apparatus was examined in detail, it was found that the power consumption efficiency (the ratio of the power consumed in the plasma to the power supplied from the high frequency power supply 1 to the plasma excitation electrode 4) was not always good. In particular, the higher the frequency supplied from the high-frequency power source, the more the power consumption efficiency decreases. The present inventors have also found that the larger the substrate size is, the more remarkable the decrease is.

In the conventional plasma processing apparatus shown in FIGS. 12, 14, 15 and 16, the value of the susceptor impedance (impedance between the susceptor and the chamber) is high. As the frequency of the high frequency increases, its impedance becomes even greater. That is, these impedances have frequency dependence. Therefore, as the frequency of the high frequency supplied from the high frequency power supply 1 increases, the high frequency current flowing through the plasma in series with the susceptor impedance decreases, and the power consumption efficiency decreases significantly.

The power consumption efficiency was investigated as follows. The chamber wall of the plasma processing apparatus is replaced with an equivalent circuit including a lumped constant circuit. The constant of each circuit is determined by measuring the impedance of the components of the chamber using an impedance analyzer. Using the fact that the impedance of the entire chamber during discharge is in a complex conjugate relationship with the impedance of a matching box having a dummy load of 50Ω on the input side, the impedance of the entire chamber during discharge is known. The plasma space is regarded as a series circuit of a resistor R and a capacitor C, and the respective constants are calculated from the values obtained in the above. Based on the equivalent circuit model of the chamber during discharge obtained by the above method, a circuit calculation is performed to derive the power consumption efficiency.

As described above, in the conventional plasma processing apparatus, the power consumption efficiency is low, so that the film forming speed is low.
For example, in the case of forming an insulating film, there is a problem that it is difficult to form an insulating film having a higher withstand voltage.

The inventor has diligently searched for the cause of low power consumption efficiency. As a result, the inventors have found that the cause of the low power consumption efficiency is as follows.

That is, first, a description will be given on the susceptor electrode 8 side of the conventional plasma processing apparatus shown in FIG.
The high frequency power is supplied from the high frequency power supply 1 to the coaxial cable, the matching circuit, the power supply plate 3 and the plasma excitation electrode (cathode electrode) 4 as shown by an arrow in FIG. On the other hand, when considering the path of the high-frequency current, the current passes through the plasma space (chamber chamber 60) via these, and then the other electrode (susceptor electrode) 8, the vertical portion of the shield 12, the bellows 11, the chamber The bottom 10b of the wall 10, the side wall 10 of the chamber wall 10
Pass through a. Then, it passes through the housing of the matching box 2 and returns to the ground of the high frequency power supply 1.

In the plasma processing apparatus shown in FIG. 14, high-frequency power from the high-frequency power supply 1 is supplied from the high-frequency power supply 1 to the cathode electrode 4 via the coaxial cable, the matching circuit, and the power supply plate 3. On the other hand, when considering the path of the high-frequency current, the current passes through the plasma space through these, and then the other electrode (susceptor electrode) 8, the shaft 13, the bottom 10b of the chamber wall 10, the chamber wall 10
Pass through the side wall 10s. Then, it passes through the housing of the matching box 2 and returns to the ground of the high frequency power supply 1.

However, in the conventional plasma processing apparatus shown in FIGS. 12 and 14, since the shaft 13 (or the vertical portion of the shield 12) of the susceptor electrode 8 and the chamber side wall 10a are parallel to each other, the forward current and the backward Is parallel between the vertical portion of the shield 12 and the side wall 10s of the chamber, resulting in an increase in mutual inductance. As a result, the power consumption efficiency is reduced, and as a result, the deposition rate is reduced or the film quality is reduced. In particular, the influence of the mutual inductance is greater as the size of the substrate 16 is increased, and as a result, the distance between the power supply plate 3 and the housing of the matching box 2 is increased.

It should be noted that the knowledge including such a problem was first found by the present inventors.

[0021]

SUMMARY OF THE INVENTION The present invention solves the problems of the prior art, has a low susceptor impedance and low frequency dependency, has a high power consumption efficiency, and has a higher film forming speed than the conventional one. It is another object of the present invention to provide a plasma processing apparatus capable of forming a higher quality film.

[0022]

The plasma processing apparatus according to the present invention is characterized in that an AC short circuit is provided between a chamber wall and an electrode having the same DC potential as the chamber.

With this short-circuit structure, the high-frequency current passes through the short-circuit portion where the mutual inductance with the chamber wall is smaller than the vertical portion of the electrode. By reducing the mutual inductance of the high-frequency current path, the efficiency of consuming high-frequency power supplied to the high-frequency current path can be significantly increased.

The short circuit must be provided as close to the chamber wall as possible in order to effectively reduce the mutual inductance.
It is desirable that the short circuit occurs within a range of less than mm.

Further, the same short-circuit occurs when the short-circuit point on the chamber side is 50
It is desirable that the distance be less than 0 mm.

The short-circuit is desirably short-circuited at a plurality of points in order to reduce the high-frequency resistance of the path of the high-frequency current through the short-circuit portion and reduce the power loss at the short-circuit portion.

The plasma processing apparatus according to the present invention is characterized in that an AC short circuit is provided between the chamber wall and a shield of an electrode having the same DC potential as the chamber. The short-circuit is substantially point-symmetric with respect to the center of the electrode so that the path through which the high-frequency current flows is uniform and the plasma processing effect is uniformly applied to the object disposed at the center of the electrode. It is desirable.

In addition, the short-circuit point is located approximately at the center of the shield so that the path through which the high-frequency current flows becomes uniform and the plasma processing effect is uniformly applied to the object disposed at the center of the electrode. It is desirable to be symmetric.

Further, the present invention provides a novel impedance measuring tool. This measuring tool has an insulation coating on the conductor,
A plurality of conductors disposed radially around the probe and electrically connected to the outer conductor of the probe; and a free end of each conductor. And a sample terminal having an equal impedance from the probe to the terminal for attachment / detachment via the conducting wire.

By using the measuring instrument having the above configuration, even if the object to be measured is large, the same impedance as during plasma processing can be accurately measured without being restricted by the distance between two measurable points. Becomes possible. In addition, by connecting a conducting wire to each of a plurality of points on the object to be measured, the impedance of the sample can be reduced. As a result, the ratio of the impedance of the DUT to the impedance of the entire measurement system including the DUT is increased, and more accurate impedance measurement can be performed.

In the impedance measuring instrument of the present invention, the specimen may be detachably attached to the probe via a probe attaching instrument which is attached by electrically connecting the other ends of the plurality of conductors. Good.

With this configuration, various specimens are prepared, and only the specimens are appropriately replaced according to the specimen, so that the impedance of the specimen having various shapes and sizes is measured using the same probe. be able to.

Preferably, the plurality of conductors are electrically connected to each other by different conductors in the middle of each conductor.

With this configuration, the impedance of the specimen can be reduced because the number of paths of the measurement current increases. As a result, the ratio of the impedance of the DUT to the impedance of the entire measurement system including the DUT is increased, and more accurate impedance measurement can be performed.

[0035]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment of Plasma Processing Apparatus) FIG. 1 shows a first embodiment of a plasma processing apparatus according to the present invention. In this plasma processing apparatus, the metal plates 80a and 80b alternately short-circuit the chamber wall 10 and the shield 12 of the electrode having the same DC potential as the chamber.

FIG. 2 shows details of the wafer susceptor electrode 8 side. In the present example, the AC short circuit between the chamber wall 10 and the shield 12 is performed at two points. In this short circuit, one end of the metal plate 80a, 80b, which is a resilient and spring body, is connected to the bottom 10b of the chamber wall 10 at short points B1 and B2, and the other end is connected to the shield 12 at short points A1 and A2. By doing so. Short-circuit point B1, B
Numeral 2 is arranged near the outermost periphery of the shield 12 so as to minimize the distance between the shield 12 and the side wall 10s of the chamber wall 10. That is, it is preferable to set the short-circuit points B1 and B2 at or near the closest point from the side wall 10s of the chamber wall 10.

As the material of the metal plate, it is preferable to use Inconel 625 (trade name) from the viewpoint that the amount of gas released in vacuum is small.
A metal plate having a size of 40 cm × 0.3 mm was used.

In this embodiment, a plate-shaped one is used.
It is also preferable to use a mesh-like material. The shape of the mesh is preferably a tortoise-like shape or a lattice shape shown in FIG. It is preferable that the mesh-shaped metal plate is cylindrically arranged along the periphery of the susceptor shield 12. FIG. 3B is a cross-sectional view taken along the line III-III of FIG. 1, and is a diagram in which a metal plate of a turtle-like mesh shown in FIG. 3A is arranged instead of the metal plates 80 a and 80 b. Since the metal plate is in a mesh shape, the vacuum exhaust in the chamber is not hindered by the metal plate, and
The flow of the high-frequency current can be made uniform. In addition, it has high elasticity and can easily follow the vertical movement of the bellows.

In this embodiment, the short-circuit points A1 and A2 in the shield 12 are set almost immediately above the short-circuit points B1 and B2.

In the plasma processing apparatus of this embodiment, the high frequency power is supplied from the high frequency power supply 1 to a coaxial cable, a matching circuit,
The power is supplied to the power supply plate 3 and the plasma excitation electrode (cathode electrode) 4. This is the same as in the conventional plasma processing apparatus. On the other hand, when considering the path of the high-frequency current, the current passes through the plasma space (chamber chamber 60) via these, and then the other electrode (susceptor electrode) 8, the horizontal portion of the shield 12, the metal plate 80a, 80b, through the bottom 10b of the chamber wall 10 and the side wall 10a of the chamber wall 10. Then, it passes through the housing of the matching box 2 and returns to the ground of the high frequency power supply 1.

In the conventional plasma processing apparatus, the high-frequency current passed through the vertical portion of the shield 12. Substrate 16
Becomes larger, the distance between the shield 12 and the side wall of the chamber inevitably increases. Mutual inductance caused by high-frequency currents flowing through the shield 12 and the chamber side wall 10s increases as the distance between them increases and power consumption efficiency decreases. Therefore, in the conventional plasma processing apparatus, power consumption is large for a large-sized substrate. The efficiency had to be low.

However, in the plasma processing apparatus according to the present embodiment, since the high-frequency current passes through the metal plates 80a and 80b closer to the chamber side wall 10s than the vertical portion of the shield 12, the generation of mutual inductance is significantly reduced, and the power consumption efficiency is reduced. Can be significantly increased.

An insulating film made of silicon nitride was formed by using the apparatus shown in FIG. 1 and the apparatus shown in FIG. 12, and the power consumption efficiency was measured. In the case of the apparatus shown in FIG. The power consumption efficiency was twice as high as that of the device shown in FIG.

Further, the susceptor impedance was measured. FIG. 4 shows the results. (A) shows the case of the plasma processing apparatus shown in FIG. 12 (conventional example), and (b) shows the case of FIG.
This is the case of the plasma processing apparatus shown in FIG.

As can be seen from FIG. 4, the susceptor impedance of the plasma processing apparatus according to the present embodiment is extremely smaller than that of the conventional plasma processing apparatus, and has less frequency dependence.

(Second Embodiment of Plasma Processing Apparatus)
FIG. 5 shows a plasma processing apparatus according to the second embodiment. This example is an example in which metal plates 80a and 80b are provided in the plasma processing apparatus shown in FIG. 14, that is, a single-frequency excitation type plasma processing apparatus.

That is, the metal plate 80a, 80b alternately short-circuits the chamber wall 10 and an electrode (susceptor electrode 8) having the same DC potential as that of the chamber. The other points are the first embodiment. This is the same as the embodiment.

(Third Embodiment of Plasma Processing Apparatus)
In this example, the influence of the position where the metal plate is provided was examined.

That is, in the apparatus shown in FIG. 1, short-circuit points B1 and B2
Are the short-circuit points A1,
Immediately below A2, the distance x from the short-circuit point to the chamber side wall 10a was changed to investigate the mutual inductance.

FIG. 6 shows the result. As can be seen from FIG. 6, the inductance starts to decrease at a distance x of 500 mm, and the decrease rate increases from around 350 mm.
From around 200 mm, the reduction rate increases more rapidly.

Accordingly, the position of the short-circuit point is preferably less than 500 mm from the side wall of the chamber, more preferably less than 350 mm, and even more preferably less than 200 mm. Most preferably, the chamber sidewall 1
0a or a point at the shortest distance from 0a.

(Fourth Embodiment of Plasma Processing Apparatus)
In this example, the influence of the number of metal plates arranged was examined.

That is, by changing the number of metal plates arranged,
The magnitude of the inductance was measured. In addition, the metal plate was arranged substantially symmetrically with respect to the center of the shield. FIG. 7 shows the result.

As shown in FIG. 7, the inductance starts to decrease by arranging the metal plates, but the reduction rate is substantially the same when four or eight metal plates are arranged. That is, saturation starts from around four. Therefore,
It is preferable to provide four. In addition, when a rectangular electrode is used, the path through which the high-frequency current flows is made uniform, and considering that the plasma processing effect is uniformly applied to the workpiece disposed at the center of the rectangular electrode, the metal plate is taken into consideration. It is preferable to provide four or eight.

(Fifth Embodiment of Plasma Processing Apparatus)
FIG. 8 shows a fifth embodiment.

In this embodiment, the metal plate 80a is arranged obliquely. That is, one end of the metal plate 80a is short-circuited at a point B1 closest to the chamber side wall in the shield 12, and the other end of the metal plate 80a is not shortly below B1 but at a point A1 from the chamber side wall, so that the metal plate is inclined. Has been placed. In addition, when the metal plate 80a is arranged obliquely, the inclination angle θ is preferably less than 45 ° from the viewpoint of suppressing the occurrence of mutual inductance.

In the fifth embodiment, the power consumption efficiency is higher than in the first embodiment.

(Sixth Embodiment of Plasma Processing Apparatus)
FIG. 9 shows a sixth embodiment.

In this embodiment, the metal plate 80a is substantially perpendicular to the chamber side wall 10a, that is, the susceptor electrode 8
Placed almost horizontally. In this example, the power consumption efficiency was further improved than in the case of the fifth embodiment.

(Seventh Embodiment of Plasma Processing Apparatus)
FIG. 10 shows a seventh embodiment.

This embodiment is an example in which a metal plate is provided in the conventional plasma processing apparatus shown in FIG.

The other points are the same as in the first embodiment.
The plasma processing apparatus according to the present example also had better power consumption efficiency, film forming speed, and dielectric strength than the conventional plasma processing apparatus shown in FIG.

(Eighth Embodiment of Plasma Processing Apparatus)
FIG. 11 shows an eighth embodiment.

This embodiment is an example in which a metal plate is provided in the conventional plasma processing apparatus shown in FIG. Other points are the same as in the first embodiment.

The plasma processing apparatus according to the present example was also superior in power consumption efficiency, film forming speed, and dielectric strength to the conventional plasma processing apparatus shown in FIG.

In the above invention, it is possible to improve the power consumption efficiency by reducing the impedance.

However, the desired power consumption efficiency has not yet been achieved. The present inventor searched for the cause, and got the idea that the cause was the impedance of the high-frequency power supply 1 and the impedance of the matching circuit.

That is, conventionally, the substrate size is also 80 cm.
Since the frequency is smaller, the plasma density is not high, and the frequency used is 13.56 MHz, the impedance of the high-frequency power supply and the impedance of the matching circuit did not affect the power consumption efficiency.
However, a high plasma density can be achieved, the substrate size becomes large, and the frequency used is 13.56M.
The idea was that the influence of the impedance of the high-frequency power supply and the impedance of the current matching circuit on the power consumption efficiency could not be neglected in a situation exceeding Hz. Conventionally, the resistance value of the high frequency power supply is 50Ω.

When a test was conducted based on this idea,
In the case where a frequency exceeding 13.56 MHz is used, it has been found that when the resistance value of the high-frequency power supply is less than 50Ω and the resistance value of the matching circuit is less than 50Ω, power consumption efficiency is improved. In addition, 10 Ω or less is more preferable.

Fixture (specimen) is semiconductor, LC
It is used for an impedance measuring device and a measuring method of a plasma device used for manufacturing a D or MR head. The conventional techniques for fixtures are as follows.

In the film forming step and the etching step, a plasma apparatus utilizing plasma generated by glow discharge using a high frequency power supply is used. In such a process, due to the parasitic impedance of the apparatus, the ratio of the effective power effectively consumed in the plasma space to the input power is reduced, which affects the deposition rate and the withstand voltage of the film, This has led to a decrease in productivity and film quality. In order to improve this, it was necessary to quantitatively understand the parasitic impedance of the device.

For such a measurement, an impedance analyzer having a coaxial probe or a network analyzer is used. However, the size of the object to be measured or the distance between two measurable points has been limited due to restrictions on the probe shape.

Conventionally, as a method for addressing this problem,
Measure and measure the size of the object to be measured on the ground side of the probe 2
The simplest method is to attach a conducting wire having a length corresponding to the distance between the points as a fixture to the ground side of the probe and to correct and use the residual impedance of the fixture.

However, the above-mentioned conventional fixture has the following problems. (1) Since the current flows asymmetrically in the measurement object, only a partial impedance of the measurement object is measured, and it is not possible to know an accurate impedance. (2) Since the current is limited by the impedance of the ground wire attached as a fixture, low impedance measurement cannot be performed accurately.

The size of the object to be measured or 2 to be measured
A dedicated fixture that can be designed to have a residual impedance value that does not affect the measurement of the impedance of the measurement target, without restricting the distance between the points and that can uniformly flow the current to the measurement target. The present inventor has conceived a novel impedance measuring instrument for the purpose of providing a measuring method.

(First Embodiment of Impedance Measuring Tool) A first embodiment of the impedance measuring tool according to the present invention will be described with reference to FIG. This fixture is characterized in that one ends of a plurality of conducting wires 101a to 101h whose impedances match each other are connected to a probe fixture 104.

The probe fixture 104 is, for example, 50 mm
A copper plate of × 10 mm × 0.5 mm is formed so that the fastening portion 106 and the ring portion are formed. The ring portion has a diameter that can be fitted to the outside of the probe 105.

The probe mounting portion 104 is connected to the conducting wire 101a.
One end of the electric motor is connected electrically by soldering or the like.

At the other end of each of the conductors 101a to 101h, a terminal (crimp terminal) 102 for attachment / detachment to / from an object to be measured (object to be measured)
a to 102 h are attached.

When using this fixture, the ring-shaped portion 104 of the probe fixture 104 is
5 and tightened by the tightening unit 106. On the other hand, each of the conductors 101a to 101h is measured at the crimping terminals 102a to 102h so as to be substantially point-symmetric,
As shown in FIG. This probe 105 is, as shown in FIG.
An insulating coating 112 is provided on the base 10 and the outer conductor 111 is coated on the insulating coating 112. The probe 105 is connected to an impedance measuring device (not shown) through a coaxial cable.

The conductors 101a to 101h may be made of, for example, aluminum, copper, silver, gold, or
Silver and gold may be plated by 50 μm or more.

After arranging the fixtures in this way, the impedance of the object to be measured was measured. The result is shown in FIG. FIG. 19A shows the result of the conventional example, and FIG.
(B) shows the result of this example. The measurement in the conventional example of FIG. 19A was performed using the probe 105 shown in FIG.

The impedance Z is represented by ωL−1 / ωC. At a certain frequency f ₀ , there is an inflection point between a hyperbola representing 1 / ωC and a straight line representing ωL, at which point the phase changes. I do. However, such a point is not clearly shown in FIG. 19A showing the result of the conventional example. On the other hand, in FIG. 19B showing the result of this example, the hyperbola, the straight line, and the inflection point clearly appear at the frequency f ₀ , and it can be seen that the impedance was accurately measured.

It is preferable to use copper having a small specific resistance for the conductors 101a to 101h in consideration of reducing the current from being limited by the impedance of the conductors 101a to 101h. The use of the conductor has an advantage that the parasitic capacitance between the conductor and the object to be measured can be reduced.

Next, using the impedance measuring device described in the present embodiment, the plasma excitation electrode (cathode electrode) 4, the plasma space 60, the susceptor electrode 8, the shield 12 horizontal sections,
Metal plate 80a, 80b, bottom 1 of chamber wall 10
0b, a method of measuring the impedance of the path leading to the side wall 10a of the chamber wall and the housing 21 will be described with reference to FIG.

First, the high frequency power supply 1 and the matching box 2 of the plasma processing apparatus are removed from the plasma processing apparatus.
The conductor 110 of the probe 105 of the impedance measuring instrument is connected to the conductor 11 connecting the matching box 2 and the power supply plate 3.
Connect to 3. Next, the crimp terminal 10 connected to the conductors 101a to 101h of the fixture of the impedance measuring instrument.
2a to 102h are screwed into the housing 21 of the plasma processing apparatus so as to be substantially point-symmetric about the power supply plate 3.
Screw. After arranging the impedance measuring tool in this way, a measurement signal is supplied to the conductor 110 of the impedance measuring tool, and the impedance of the path from the power supply plate 3 of the plasma processing apparatus to the housing 21 via the plasma space 60 is measured.

The fixture is attached to a measurement probe which has been calibrated at 0S, 0Ω, and 50Ω, respectively, and used. The effect of the residual impedance of this fixture can be solved by performing open and short correction. It is possible. Note that the same effect can be obtained as shown in FIG. 20 by performing the above calibration on the probe with the fixture attached.

(Second Embodiment of Impedance Measuring Tool) FIG. 18 shows a second embodiment of the impedance measuring tool according to the present invention. This impedance measuring instrument is used when the object to be measured is large.
Between 1a and 101h, another short-circuiting conductor 108 is used for short-circuiting.

According to this impedance measuring instrument, the path of the measurement current is increased, so that the impedance of the specimen can be reduced. As a result, the ratio of the impedance of the device under test to the total impedance of the measurement system including the device under test increases, and more accurate impedance measurement is possible.

(Third Embodiment of Impedance Measuring Tool) FIG. 22 shows a third embodiment of the impedance measuring tool according to the present invention. In the present embodiment, the first
Conductors 101a to 101h according to the embodiment of the present invention.
One end of the probe 1 directly without the probe fixture
The first embodiment differs from the first embodiment in that the outer conductor 111 is connected to the outer conductor 111 by soldering with a solder terminal 121.
The other parts are the same as in the first embodiment. In this embodiment, the same effects as those of the first embodiment according to the impedance measuring instrument of the present invention are obtained.

[0091]

According to the present invention, power consumption efficiency can be increased, and a film can be formed with a higher film forming speed and a higher quality than before. Further, the susceptor impedance can be reduced and the frequency dependency can be reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view of a plasma processing apparatus according to a first embodiment of the plasma processing apparatus.

FIG. 2 is an enlarged view near a susceptor electrode in FIG. 1;

3A is a partial side view of a mesh-like metal plate, and FIG. 3B is a plan view thereof.

FIG. 4 is a graph showing measurement results according to the first embodiment of the plasma processing apparatus and a conventional example.

FIG. 5 is a sectional view of a plasma processing apparatus according to a second embodiment of the plasma processing apparatus.

FIG. 6 is a graph showing a relationship between a distance between a metal plate and a chamber wall and a mutual inductance.

FIG. 7 is a graph showing the influence of the number of metal plates arranged.

FIG. 8 is a sectional view showing a part of a plasma processing apparatus according to a fifth embodiment of the plasma processing apparatus.

FIG. 9 is a sectional view showing a part of a plasma processing apparatus according to a sixth embodiment of the plasma processing apparatus.

FIG. 10 is a sectional view showing a plasma processing apparatus according to a seventh embodiment of the plasma processing apparatus.

FIG. 11 is a sectional view showing a plasma processing apparatus according to an eighth embodiment of the plasma processing apparatus.

FIG. 12 is a cross-sectional view of a plasma processing apparatus according to a conventional example.

FIG. 13 is a partially enlarged view of a susceptor electrode shown in FIG. 12 and a peripheral portion thereof.

FIG. 14 is a sectional view of a plasma processing apparatus according to another conventional example.

FIG. 15 is a sectional view of a plasma processing apparatus according to another conventional example.

FIG. 16 is a sectional view of a plasma processing apparatus according to another conventional example.

FIG. 17 is a view showing a first embodiment of the impedance measuring instrument of the present invention.

FIG. 18 is a view showing a second embodiment according to the impedance measuring instrument of the present invention.

FIG. 19 is a graph showing the results of measurement using the impedance measuring instrument shown in FIG.

FIG. 20 is a graph showing a result of measurement using the impedance measuring instrument shown in FIG. 17;

21 is a diagram showing a method for measuring the impedance of the plasma processing apparatus shown in FIG. 1 using the impedance measuring tool shown in FIG.

FIG. 22 is a perspective view showing a third embodiment of the impedance measuring instrument according to the present invention.

FIG. 23 is a perspective view showing a probe used for the impedance measuring instrument shown in FIGS. 17, 18, and 22.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 High frequency power supply, 2 Matching box, 3 Power supply plate, 4 Plasma excitation electrode (cathode electrode), 5 Shower plate, 6 Space, 7 holes, 8 Plasma excitation electrode (wafer susceptor, susceptor electrode), 9 Insulator, 10 Chamber wall 10a chamber side wall, 10b chamber wall bottom, 10s chamber side wall, 10u chamber upper part, 11 bellows, 12 susceptor shield, 13 shaft, 14 matching box, 15 high frequency power supply, 16 substrate, 17 gas introduction pipe, 21 housing, 20 shield, 60 chamber chamber, 80a, 80b metal plate, 101a-101h conducting wire, 102a-102h crimp terminal, 104 probe mounting fixture, 105 probe, 106 fastening part, 111 outer conductor, 112 insulating coating, 114 screw, 12 Short-circuit point, A1, A2 short-circuit point, B1, B2 short-circuit point.

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Yo Nakano 1-7 Yukitani Otsuka-cho, Ota-ku, Tokyo Alps Electric Co., Ltd. (72) Inventor Koichi Fukuda 3-31 shares of Meidori, Izumi-ku, Sendai, Miyagi Prefecture. Front Tech Co., Ltd. (72) Inventor Kim Seok-Lt 533 El-Gee Research Complex, 533, Hugye-dong, Dong'an-gu, Anyang-si, Gyeonggi-do, Republic of Korea (72) Inventor Yasuhiko Kasama 3-31 Ametori Izumi-ku, Sendai City, Miyagi Prefecture Inside Frontec Co., Ltd. (72) Inventor Tadahiro Omi 2-1-17-301 Yonegabukuro, Aoba-ku, Sendai, Miyagi Prefecture (72) Inventor Shoichi Ono 1-7 Yukitani Otsuka-cho, Ota-ku, Tokyo Alps Electric Co., Ltd.

Claims (10)

[Claims] 1. A plasma processing apparatus, wherein an AC short circuit is provided between a chamber wall and an electrode having the same DC potential as the chamber. 2. A plasma processing apparatus, wherein an AC short circuit is provided between a chamber wall and a shield of an electrode having the same DC potential as the chamber. 3. 500 mm horizontally from the side wall of the chamber
2. A short circuit in a range of less than
The plasma processing apparatus as described in the above. 4. The plasma processing apparatus according to claim 1, wherein the short-circuit point on the chamber side is less than 500 mm in a horizontal direction from the side wall of the chamber. 5. The plasma processing apparatus according to claim 1, wherein a short circuit occurs at a plurality of points. 6. The plasma processing apparatus according to claim 5, wherein the short-circuit point is substantially point-symmetric with respect to the center of the electrode. 7. The plasma processing apparatus according to claim 5, wherein the short-circuit point is substantially point-symmetric with respect to the center of the shield. 8. A probe comprising an insulating coating provided on a conducting wire, a probe having an outer conductor covered on the insulating coating, and radially centered on the probe and electrically connected to the outer conductor of the probe. A sample comprising a plurality of conductors arranged and terminals for attachment / detachment to / from an object to be measured provided at the free ends of the respective conductors, wherein the impedance from the probe to the attachment / detachment terminals via the conductors is equal. An impedance measuring instrument comprising: 9. The probe according to claim 1, wherein the sample is detachably attached to the probe via a probe attachment which is attached by electrically connecting the other ends of the plurality of wires. 9. The impedance measuring instrument according to 8. 10. The impedance measuring instrument according to claim 8, wherein the plurality of conductors of the sample are electrically connected to each other by different conductors in the middle of each conductor.