JP5139029B2 - Plasma processing equipment - Google Patents

Description

  The present invention relates to a plasma processing apparatus having a plurality of inductive coupling elements.

Conventionally, as this kind of plasma processing apparatus, those shown in Patent Document 1 and Patent Document 2 are known.
In Patent Document 1, a plurality of concentric coil units are arranged on the ceiling side of the vacuum chamber, and an RF power source that applies a high frequency to the plurality of coil units is provided. Further, an RF shield is arranged so as to cover the outer peripheral side of each coil unit. This publication discloses that the shield is formed of an iron material as a magnetic material or an aluminum material.

Also in Patent Document 2, similarly, a plurality of concentric coil units arranged on the ceiling side of the vacuum chamber, an RF power source that collectively applies a high frequency to the plurality of coil units, and each coil unit The mutual interference reducing means arranged so as to cover the outer peripheral side of the.
US Pat. No. 5,683,548 JP 2000-58296 A

In order to provide a more powerful and uniform plasma processing apparatus, when an RF power supply is individually installed to control power supply to a plurality of coil units, electromagnetic coupling occurs between the plurality of coil units. Cheap. When electromagnetic coupling occurs, power is supplied from one coil unit to the other coil unit.
In general, the matching box detects an incident wave and a reflected wave between an RF power source and a coil unit, and dynamically performs impedance matching for preventing the most reflected wave. However, when the above-described electromagnetic coupling occurs, an external factor cannot be eliminated even if impedance matching is attempted, and the matching box cannot be controlled.

On the other hand, the conventional plasma processing apparatus described above has the following problems.
In the technique disclosed in Patent Document 1, a high frequency is applied collectively from a single RF power source to a plurality of coil units, and the above-described problem of independence of the RF power source cannot be solved as it is. Therefore, it does not lead to solving the problems caused by individualizing the RF power source and the matching box.
The same problem occurs in the one shown in Patent Document 2.
Furthermore, in the thing shown in patent document 1 and patent document 2, although the RF shield is arrange | positioned also at the outer peripheral side of the largest diameter coil unit, if RF power supply is connected to each coil unit, it will flow into the RF shield of an outer peripheral side. Loss due to current occurs. This loss increases as the electric power supplied to each coil unit increases. Therefore, there is a problem that the current loss caused by the RF shield disposed on the outer peripheral side of the maximum diameter coil unit is very large.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a plasma processing apparatus capable of improving the uniformity of generated plasma while reducing current loss.

  To achieve the above object, the present invention provides a vacuum chamber in which a plasma processing space is formed, a plurality of inductive coupling elements attached to the vacuum chamber, and individually applying a high frequency to the plurality of inductive coupling elements. A plurality of power supply means, a plurality of impedance matching means for impedance matching when a high frequency is applied to the inductive coupling element, and an outermost inductive coupling element provided between the plurality of inductive coupling elements It is set as the structure provided with the electromagnetic coupling reduction means which is not arrange | positioned on the outer side.

At least the following matters will become clear from the description of the present specification and the accompanying drawings.
According to the configuration of the above invention, the plurality of power supply units individually apply the high frequency to the plurality of inductive coupling elements attached to the vacuum chamber via the impedance matching unit. An alternating electromagnetic field is generated from the plurality of inductive coupling elements, but electromagnetic coupling mitigating means is provided between the inductive coupling elements, so that almost no electromagnetic coupling occurs between the inductive coupling elements. For this reason, each impedance matching means performs impedance matching based only on the relationship between the incident wave and the reflected wave between the inductive coupling element and the power supply means without being affected by others.

As described above, according to the present invention, by providing independent power supply means for each inductive coupling element, it is possible to perform fine control over each inductive coupling element and to perform electromagnetic coupling with other inductive coupling elements. Thus, it becomes possible to prevent the impedance matching means from being out of control.
The impedance matching means is often called a matching box as an actual product, but any name can be used as long as impedance matching is performed as a function thereof.
In providing the impedance matching means, two modes are practical. The first is the case where the impedance matching means exists alone and is interposed between each pair of the inductive coupling element and the power supply means, and the second is the impedance matching means in the power supply means. This is the case.

In any case, it is provided to reduce high-frequency current loss applied from one power supply means, and the present invention is applicable.
The reason why the impedance matching means cannot perform the original control by electromagnetic coupling is due to the energy supplied by electromagnetic coupling from other power supply means. Therefore, it is necessary to reduce the electromagnetic coupling between the inductive coupling elements for each pair of the impedance matching means and the power supply means.
In view of such an environment, the impedance matching means is paired with the power supply means, and the electromagnetic coupling reducing means is provided for each set of inductive coupling elements connected to the impedance matching means. A configuration such as this is also possible.

In such a configuration, electromagnetic coupling mitigation means is provided between inductive coupling elements with different power supply means. It can be said that there is no influence from. Therefore, each impedance matching means does not become defective in control.
Each inductive coupling element can be arranged on a one-to-one basis with respect to the pair of the impedance matching means and the power supply means. It is also possible to provide supply means.

  In other words, in the former, one inductive coupling element is connected to a set of the impedance matching means and the power supply means, and one electromagnetic coupling mitigation corresponding to the one inductive coupling element. In the latter case, a plurality of inductive coupling elements are connected to a set of the impedance matching means and the power supply means, and the plurality of inductive coupling elements are combined into a set. One electromagnetic coupling mitigation means corresponds to

As described above, if an RF shield exists outside the outermost inductive coupling element, current loss is large. For this reason, in this invention, it can also be set as the structure by which the said electromagnetic coupling reduction means is not arrange | positioned outside the said inductive coupling element of the outermost periphery.
The electromagnetic coupling reducing means reduces electromagnetic coupling generated between the inductive coupling elements by an alternating electromagnetic field generated at a high frequency applied from another power supply means, and generally corresponds to a grounded good conductor. As a specific example, the electromagnetic coupling mitigation means can be formed of a band-shaped metal ring.

  By the way, in such a plasma processing apparatus, plasma uniformity is an important factor. For this reason, the said strip | belt-shaped metal ring can be set as the structure which adjusts the degree of the electromagnetic coupling between the said inductive coupling elements by setting it as the shape from which a width | variety changes with parts. If there is a metal body grounded between the inductive coupling elements, the electric field is affected by its presence. In general, if there is a ground conductor, the potential of the space in the vicinity of the ground conductor must be very close to the ground potential. Since the range affected by this depends on the shape of the conductor, the influence can be adjusted by changing the width of the band-shaped metal ring.

Originally, electromagnetic coupling with a nearby inductive coupling element, which is a disadvantage, can be made to act as an adjustment means in this way.
As an example of adjusting the electromagnetic coupling, the band-shaped metal ring can be configured so that there are a thick part and a thin part depending on the part.
As another example, the band-shaped metal ring can be configured to have a cut in the width direction depending on a portion.
In either case, if the width of the ground conductor is increased, the portion where the potential is close to the ground potential in the space is increased, and if the width of the ground conductor is decreased, the portion where the potential is close to the ground potential is decreased in the space. . As a result, the degree of electromagnetic coupling between the inductive coupling elements increases and decreases. Of course, the notch will make the ground conductor smaller. Therefore, these can also be used as a means for adjusting uniformity.

  As an example of a more specific configuration of the above-described means, the plurality of inductive coupling elements are configured by a plurality of concentric coils, and the vacuum chamber is configured by a vacuum chamber lid portion and a vacuum chamber body portion. The vacuum chamber lid is formed with a plurality of concentric coil receiving grooves capable of receiving the plurality of coils on the side facing the outside of the vacuum chamber, and on the side facing the inside of the vacuum chamber. A plurality of concentric annular plasma generating grooves are formed inside the groove, and the band-shaped metal ring is disposed so as to be interposed between the inductive coupling elements in the coil receiving groove; can do.

Further, assuming such a configuration, the coil receiving groove has a bottom surface formed substantially horizontally, an inner peripheral wall surface and an outer peripheral wall surface formed substantially vertically, respectively, It is arrange | positioned in the surrounding side wall surface vicinity, The said strip | belt-shaped metal ring can be set as the structure arrange | positioned in the said outer peripheral side wall surface vicinity.
This specific configuration will be described in detail below based on the drawings.
FIG. 1 schematically shows a plasma processing apparatus according to an embodiment of the present invention.

In FIG. 1, a plasma processing apparatus 10 includes a vacuum chamber body 12 having a plasma processing space 11 formed therein, a vacuum chamber lid 13 (vacuum chamber), and coils (coil units: plural) attached to the vacuum chamber. Inductive coupling elements) 14-16, RF power sources (power supply means) 17-19 for applying a high frequency to the plurality of inductive coupling elements 14-16, and matching boxes (impedance matching means) 21-23. ing.
Further, the vacuum chamber main body 12 is connected to a vacuum pump for ensuring a vacuum pressure suitable for plasma maintenance, and is exhausted through a through hole (not shown).

The vacuum chamber lid 13 is made of an insulating material such as ceramic, and plasma generating spaces (plasma generating annular grooves) 31 to 33 are formed on the side facing the plasma processing space 11. The plasma generation spaces 31 to 33 are annular grooves engraved concentrically, and are arranged to extend linearly along the adjacent surfaces of the vacuum chamber lid portion 13 and the plasma processing space 11 while communicating with the plasma processing space 11. Will be.
The plasma gas is composed of a plasma generation gas and a processing gas, and is supplied from an external gas unit to the plasma generation spaces 31 to 33 via a nozzle disposed on the ceiling surface of the annular groove. It is fed into the processing space 11. As the gas for generating plasma, an inert gas that does not chemically react such as argon is used, and as the processing gas, a gas obtained by mixing an appropriate amount of diluent gas with a reactive gas such as CF gas or silane gas is supplied. It has become.

On the side facing the outside of the vacuum chamber in the vacuum chamber lid portion 13, coil housing grooves 34 to 36 are formed as annular grooves engraved concentrically on the outside surrounding the plasma generation spaces 31 to 33. is there. Each of the coil receiving grooves 34 to 36 accommodates one coil 14 to 16 and each of the coil receiving grooves 34 and 35 serving as an annular groove between the innermost circumference and the intermediate groove has a belt-like metal plate. The band-shaped metal rings 44 and 45 which consist of are accommodated.
The coils 14 to 16 are two-turn coils, and are disposed in the coil receiving grooves 34 to 36 which must be very narrow, so as to approach the vicinity of the inner peripheral side wall surface. Further, the band-shaped metal rings 44 and 45 are arranged so as to be close to the vicinity of the outer peripheral side wall surface in the coil receiving grooves 34 and 35. The coils 14 to 16 are not necessarily 2 turns, and may be a coil of 1 turn or 3 turns or more depending on various conditions.

  The band-shaped metal rings 44 and 45 are band-shaped rings having a predetermined width, the band-shaped metal ring 44 is between the innermost coil 14 and the middle coil 15, and the band-shaped metal ring 45 is the middle coil 15. And the outermost peripheral coil 16. The band-shaped metal rings 44 and 45 are formed of a conductor and are grounded (ground conductor). By forming it from a band-shaped metal material, it becomes wider than the coils 14 to 16, and as will be described later, the alternating electromagnetic field generated by the coils 14 to 16 is affected by the electric field strength due to the presence of the ground conductor. This makes it difficult for electromagnetic coupling to occur.

Although it is difficult to completely break the electromagnetic coupling, the influence can be almost ignored by arranging such a ground conductor between each other while generating alternating electromagnetic fields having the same strength. On the other hand, if the width is different, the degree of electromagnetic coupling and the space potential distribution can be slightly adjusted. These help to improve plasma uniformity.
On the other hand, in the plasma processing space 11, a cathode portion 24 on which the workpiece 51 is mounted is installed, and this cathode portion 24 is supported by a support (not shown) implanted in the inner bottom of the vacuum chamber body 12. The RF power source 26 is connected via the matching box 25.

  FIG. 2 is a schematic circuit diagram showing the coils 14 to 16, the RF power sources 17 to 19, and the matching boxes 21 to 23. When applying a high frequency from the RF power sources 17 to 19 to the coils 14 to 16, matching boxes 21 to 23 as impedance matching means are inserted in order to make the reflected power of the output of the RF power source zero. The matching boxes 21 to 23 theoretically adjust the internal variable capacitors so that the output impedance viewed from the RF power source is constant and the phase angle is zero.

FIG. 3 shows an internal circuit of the matching box, which has a circuit configuration for performing general-purpose π-type impedance conversion.
The matching box is a variable inductance connected between the fixed inductances L1 and L2 interposed in series between the RF power source and the load, and the capacitance of which can be changed and is connected between the front stage and the rear stage of the fixed inductance L2. C1 and C2 and a detector D that outputs a predetermined control signal.
The detector D detects the impedance of the voltage and current supplied from the RF power source and the phase difference between the voltage and current, and the capacitances of the variable capacitors C1 and C2 are determined based on the detected impedance and phase difference. A control signal is output for adjustment.

Such control can be realized by analog control or digital control.
In the case of the matching box shown in FIG. 3, it is separated from the RF power source and is interposed between the coils 14 to 16 and the RF power sources 17 to 19 independently. However, the matching box itself can be realized by being integrated with the RF power source in the sense that impedance matching is performed. In this sense, the former corresponds to a case where a matching box is interposed between each pair of the inductive coupling element and the power supply means, and the latter is a case where the matching box is incorporated in the power supply means. It corresponds to the case.

  For example, if a single matching box and an RF power source are connected to the coils 14 to 16, the detector D of the matching box is supplied from the RF power source to the coils 14 to 16 that are loads. It is possible to achieve impedance matching only from the relationship between the wave and the reflected wave. At this time, even if electromagnetic coupling occurs from one coil to another coil and power is supplied, the relationship between the incident wave and the reflected wave does not change from the matching box, so there is no need to consider anything. . On the other hand, when the coils 14 to 16 are supplied with power from a plurality of RF power sources, if power is supplied by electromagnetic coupling between the coils 14 to 16, the reflected wave and the incident wave are used even if impedance matching is attempted. Will become unstable and cannot be properly aligned. In the meantime, the control signal output from the detector D is not appropriate and causes control failure. Needless to say, a poor control of the matching box leads to a malfunction of the entire power control system including the RF power supply.

4 to 6 show perspective views of the band-shaped metal ring.
FIG. 4 shows a band-shaped metal ring having the most basic configuration, which is formed from a band-shaped metal plate having a constant width over the entire circumference. By arranging the ground conductor between the coils 14 to 16 in the band-shaped metal ring, the alternating electromagnetic field generated by each coil 14 to 16 affects another coil 14 to 16 located on the opposite side beyond the ground conductor. To reduce the occurrence of so-called electromagnetic coupling. The electric field strength in the space generated by each alternating electromagnetic field is influenced by the presence of the ground conductor. Therefore, the shape of the ground conductor, such as width and thickness, is useful for adjusting the distribution of the conductive field strength.

  FIG. 5 shows an example in which the width of the band-shaped metal plate is partially narrowed. Of course, it is also possible to increase the width partially. FIG. 6 shows an example in which a plurality of cuts are formed in the width direction with respect to the band-shaped metal plate. Of course, it is possible to partially form a plurality of small protrusions on the contrary. In the case of notches and small projections, the influence on the distribution of the electric field strength is considered to be slightly reduced. Therefore, the width is broadened by varying the width as shown in FIG. 5, and fine adjustment is performed as shown in FIG. It is preferable to use a notch or small protrusion.

By the way, if the strip-shaped metal rings 44 and 45 are disposed close to the coils 14 and 15 that generate the alternating electromagnetic field, a loss occurs because eddy current flows on the strip-shaped metal plate by the alternating electromagnetic field. This loss is proportional to the electromotive voltage.
Each of the coils 14 to 16 applies an alternating electromagnetic field to the plasma generation spaces 31 to 33 located inside thereof, thereby converting the plasma generating gas into plasma. Since the energy required for plasma formation in a predetermined space is a certain value or more, the larger the plasma generation spaces 31 to 33, the larger the required power. That is, in the coils 14 to 16, the required power increases from the inner peripheral side toward the outer peripheral side, and the power supplied from the RF power sources 17 to 19 increases in the same manner. This power ratio is approximately 1: (2-3) :( 5-6).

That is, if the belt-shaped metal rings are arranged on the outermost circumference in the same manner as the innermost circumference and the middle, the loss caused by the outermost circumference coil 16 is 5 to 6 times that of the innermost circumference. 5/3 to 3 times as large as the above. Loss of one coil does not mean a 1/3 loss reduction.
However, in this invention, it arrange | positions only between the coils 14-16 to the last, and does not arrange | position outside the outermost coil 16. None of the conventional techniques does not arrange a ground conductor on the outermost periphery. Further, the loss that can be reduced by not arranging the ground conductor on the outermost periphery is very large, but the effect is great.

FIG. 7 is a graph showing the power supplied on the horizontal axis and the current value flowing through the coil 16 on the vertical axis. In the experiment, measurement was performed with and without a similar band-shaped metal ring disposed on the outer peripheral side of the coil 16. In addition, in the presence or absence of a band-shaped metal ring, the measurement results in the presence of 10 mTorr of argon gas and in the presence of 100 mTorr, respectively.
For example, when the strip-shaped metal rings 44 and 45 are disposed, the current value flowing through the coil 16 when supplying 1000 Watt power is about 8.5 A in both cases of 10 mTorr and 100 mTorr due to the presence of the loss described above.

On the other hand, when the band-shaped metal ring is not disposed, the above-described loss does not exist, so that the current value flowing through the coil 16 when supplying 1000 Watt is about 12.5 A when the power is 10 mTorr, and about 12 when the power is 100 mTorr. 0A.
This experimental result also demonstrates that current loss can be extremely reduced while reducing or preventing electromagnetic coupling between the coils 14 to 16.
Next, the operation of the present embodiment configured as described above will be described.

  In the above-described configuration, the workpiece 51 is carried onto the cathode portion 24 through a gated through hole (not shown), and when the plasma processing space 11 reaches a predetermined gas pressure or the like, the RF power sources 17 to 19 are connected to the coil 14. When a high frequency is applied to .about.16, the gas in the plasma generation spaces 31 to 33 is excited by the alternating electromagnetic fields generated from the coils 14 to 16, and plasma is generated and formed here. The plasma generated in the plasma generation spaces 31 to 33 is blown out to the communicating plasma processing space 11, and the upper surface of the workpiece 51 placed on the cathode portion 24 in the plasma processing space 11 is exposed to the plasma. The As a result, plasma processing is performed on the workpiece 51. At that time, if the RF power source 26 is also operated, anisotropy can be imparted to the plasma processing.

  When applying a high frequency from each RF power source 17-19 to the coils 14-16, each RF power source oscillates at a predetermined frequency to generate a high frequency. The high frequency passes through the matching boxes 21 to 23 and is applied to the coils 14 to 16. The alternating electromagnetic fields generated from the coils 14 to 16 propagate not only to the plasma generation spaces 31 to 33 but also around the coils 14 to 16 to form an electromagnetic field. The space potential formed by the same electromagnetic field affects the potential of the peripheral object, and as a result, the space potential is in a predetermined state. At this time, if there is a ground conductor, a space potential corresponding to the potential difference is formed between the ground conductor and the coils 14 to 16. Of course, the space potential is affected by the size and shape of the ground conductor. However, when the strip-shaped metal rings 44 and 45 are arranged between the coils 14 to 16 as in the present embodiment, each of the coils 14 to 16 has its own strip-shaped metal rings 44 and 45. The positional relationship is most unlikely to be affected by the space potential formed by the other coils 14 to 16. Therefore, although it cannot be said that the electromagnetic coupling between the coils 14 to 16 does not occur at all, it is greatly reduced. In this sense, the belt-shaped metal rings 44 and 45 are the electromagnetic coupling reducing means of the present invention.

  Therefore, each matching box 21 to 23 is purely configured to reduce the reflected wave as much as possible based on the relationship between the incident wave and the reflected wave supplied from the RF power sources 17 to 19 to the coils 14 to 16. Impedance matching is performed by changing C2. At this time, since there is no electromagnetic coupling with other coils, there is no control based on an unknown component in controlling the capacitance change of the variable capacitors C1 and C2, which is accompanied by oscillation, divergence, etc. in the matching boxes 21-23. There is no control failure and no failure is induced.

  Since the shape and position of the ground conductor affect the space potential as described above, various shapes can be employed as the electromagnetic coupling reducing means. As an example, in addition to the basic shape shown in FIG. 4, a band-shaped metal ring having a different width depending on the portion shown in FIGS. 5 and 6 can be used. Although it has a surface which adjusts the degree of the electromagnetic coupling between each coil by utilizing such a strip-shaped metal ring, the purpose is the uniformity of the generated alternating electromagnetic field. Therefore, it is not intended only for the degree of electromagnetic coupling but also for adjusting the spatial potential distribution.

In the present embodiment, a plurality of concentric annular grooves (plasma generating spaces 31 to 33 and coil housing grooves 34 to 36) are formed on the front surface and the back surface of the vacuum chamber lid portion 13. Since these are positioned so as to be nested with each other, the plasma generation spaces 32 and 33 are located between the coil receiving grooves 34 to 36. Therefore, a ground conductor cannot be installed at this position.
Therefore, in order to arrange the band-shaped metal rings 44 and 45 between the coils 14 to 16, the coils 14 to 16 and the band-shaped metal rings 44 and 45 are arranged as shown in FIG. That is, the coils 14 to 16 are arranged so as to be close to the vicinity of the inner peripheral side wall surface in the coil housing grooves 34 to 36. The band-shaped metal rings 44 and 45 are arranged so as to approach each other in the vicinity of the outer peripheral side wall surface of the coil housing grooves 34 and 35. And both are arrange | positioned, without contacting.

  In the above-described embodiment, the coils 14 to 16, the matching boxes 21 to 23, and the RF power sources 17 to 19 are connected independently one by one. However, when a matching box and an RF power source are paired, a plurality of coils can be connected as a load. In this case, the band-shaped metal ring is required between coils connected to different sets when the matching box and the RF power source are paired. For example, a high frequency is applied to two coils by one set of matching box and RF power source, and a high frequency is applied to the other coil by another set of matching box and RF power source. In this case, the first two coils are regarded as one, and one band-shaped metal ring is required between the second coil and the subsequent coil.

  It is natural that the band-shaped metal ring itself has a substantially annular shape on the assumption that the coil is circular. However, in view of the purpose of reducing electromagnetic coupling between a plurality of coils, it is not always necessary to have an annular shape. It is technically possible to form a rectangular ring-shaped metal ring with respect to a square coil. Also, in order to make the installation conductor that reduces electromagnetic coupling with a small area between the two coils, a band-shaped metal ring made of a band is efficient, but the shape of the installation conductor covers or blocks more parts. It is also possible to do. Moreover, it may be a shape that cannot be said to be a ring shape because a part of a plate shape is attached to the part, or may not be a complete ring that is partially open.

  As described above, when the plasma is generated and formed by connecting the matching boxes 21 to 23 and the RF power sources 17 to 19 independently to the plurality of coils 14 to 16 and applying a high frequency, the coils 14 to 16 are generated. By arranging the band-shaped metal ring as the installation conductor between ˜16, the electromagnetic coupling between the coils 14-16 is inhibited / reduced, and the control of the matching boxes 21-23 is prevented while being accurate. It is also possible to reduce the current loss by guaranteeing impedance matching and not intentionally arranging the strip metal ring outside the outermost coil 16.

Needless to say, the present invention is not limited to the above embodiments. It goes without saying for those skilled in the art,
・ Applying mutually interchangeable members and configurations disclosed in the above embodiments by appropriately changing the combination thereof.− Although not disclosed in the above embodiments, it is a publicly known technique and the above embodiments. The members and configurations that can be mutually replaced with the members and configurations disclosed in the above are appropriately replaced, and the combination is changed and applied. It is an embodiment of the present invention that a person skilled in the art can appropriately replace the members and configurations that can be assumed as substitutes for the members and configurations disclosed in the above-described embodiments, and change the combinations and apply them. It is disclosed as.

It is the schematic which shows the plasma processing apparatus concerning one Embodiment of this invention. It is a typical circuit diagram of a coil, RF power supply, and a matching box. It is a block diagram of the internal circuit of a matching box. It is a perspective view of a strip-shaped metal ring. It is a perspective view of the strip | belt-shaped metal ring concerning a modification. It is a perspective view of the strip | belt-shaped metal ring concerning a modification. It is a graph which shows the electric power supplied to a horizontal axis, and shows the electric current value which flows into a coil on a vertical axis | shaft.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Plasma processing apparatus 11 ... Plasma processing space 12 ... Vacuum chamber main-body part 13 ... Vacuum chamber cover parts 14-16 ... Coil (inductive coupling element)
17 to 19: RF power supply (power supply means)
21-23 ... matching box 24 ... cathode part 25 ... matching box 26 ... RF power supply 31-33 ... plasma generation space (annular groove for plasma generation)
34-36 ... Coil housing grooves 44, 45 ... Band-shaped metal ring 51 ... Object D ... Detectors C1, C2 ... Variable capacitors L1, L2 ... Inductance

Claims (8)

A vacuum chamber formed with a plasma processing space and composed of a vacuum chamber lid and a vacuum chamber body ;
A plurality of inductive coupling element that is attached to the vacuum chamber,
A plurality of power supply means for individually applying a high frequency to the plurality of inductive coupling elements;
A plurality of impedance matching means for performing impedance matching when applying a high frequency to the inductive coupling element, wherein the power supply means is paired between each pair of the inductive coupling element and the power supply means. A plurality of impedance matching means interposed respectively ,
Wherein an electromagnetic coupling reducing means provided between the plurality of inductive coupling elements, and a electromagnetic coupling reducing means provided for each set of the inductive coupling element connected to said impedance matching means,
A plurality of inductive coupling elements are connected to a set of the impedance matching means and the power supply means, and one electromagnetic coupling mitigation means corresponds to the plurality of inductive coupling elements as a set. ,
The inductive coupling element is composed of a plurality of concentric coils,
The vacuum chamber lid is formed with a plurality of concentric coil receiving grooves that can receive the plurality of coils on the side facing the outside of the vacuum chamber, and on the side facing the inside of the vacuum chamber. A plurality of concentric annular plasma generating grooves are formed inside the groove,
The coil housing groove has a bottom surface formed substantially horizontally, an inner peripheral side wall surface and an outer peripheral side wall surface each formed substantially vertical,
The coil is disposed in the vicinity of the inner peripheral side wall surface,
The electromagnetic coupling reducing means is disposed so as to be interposed between the coil and the outer peripheral side wall surface in the coil housing groove.
Flop plasma processing apparatus. The Symbol impedance matching means, the plasma processing apparatus according to 請 Motomeko 1 characterized in that it is incorporated within the power supply unit. Against a set of the impedance matching means and said power supply means, is connected to one of said inductive coupling elements, one of said electromagnetic coupling reducing means in response to the inductive coupling elements of this one corresponds the plasma processing apparatus according to 請 Motomeko 1 you wherein a. It said electromagnetic coupling relief means, plasma processing apparatus according to any one of claims 3 to 請 Motomeko 1 you, characterized in that the outside of the outermost of the inductive coupling element is not disposed. It said electromagnetic coupling relief means, plasma processing apparatus according to any one of claims 4 to be composed of a strip-shaped metal ring from 請 Motomeko 1 shall be the features. The strip metal ring is a width different shapes depending on the site, a plasma processing apparatus according to 請 Motomeko 5 you and adjusting the degree of electromagnetic coupling between the inductive coupling element. The strip metal ring plasma processing apparatus according to 請 Motomeko 6 you, characterized in that there are a wide width portion and a thin portion by portion. The strip metal ring plasma processing apparatus according to 請 Motomeko 6 characterized as having a cut in the width direction by the site.

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