JPH11149998A - Plasma treating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To uniformly conduct plasma treatment. SOLUTION: An exhaust path 28 opening an exhaust opening 16 toward a plasma treating space 13 is formed in a flat plate 11 on one side or a second mechanism 21 on a plasma generating space 22 side. The exhaust openings 16 are dispersed. Difference in distance moving for exhausting treatment-finished gas between the central part and the peripheral part of the plasma treating space is decreased, and as a result, uniformity exceeding uniformity obtained by the uniform supply of plasma or treating gas can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a plasma processing apparatus (plasma reactor) such as a plasma film forming apparatus and a plasma etching apparatus, and relates to an IC (semiconductor device).
The present invention relates to a plasma processing apparatus suitable for performing a plasma process, that is, a process based on a plasma reaction on a substrate or the like in a high-precision manufacturing process such as an LCD, a liquid crystal display panel (LCD), or a plasma display panel (PDP).

[0002]

2. Description of the Related Art As a typical example of a plasma processing apparatus, a plasma processing space is formed between a pair of parallel flat plates serving as counter electrodes, and an etching process (plasma process) is performed on a substrate (workpiece) such as a silicon wafer. A so-called parallel plate type etcher (RIE) for performing the above-mentioned is known. In such a parallel plate type plasma processing apparatus, a pair of parallel plates are provided in a vacuum chamber in a line up and down or left and right,
Plasma is generated or introduced into a plasma processing space formed between the two flat plates, and a predetermined processing gas or the like is also introduced into the plasma processing space. Then, a plasma reaction is performed in the plasma processing space, whereby the substrate surface in the plasma processing space is subjected to an etching process. In this case, for uniform processing, there is a type in which a processing gas supply port is formed in one of a pair of parallel flat plates, and a type in which the processing gas supply ports are dispersed in a large number.

On the other hand, a plasma processing space, a plasma generating space, and a plasma space are connected to each other in order to reduce damage to the object by ions and prevent the object from being directly exposed to the high-density plasma being generated. (Electron cyclotron resonance) and
JP-A-81324 discloses a device in which both spaces are spaced apart from each other, and a high-density plasma such as an inductively coupled plasma (ICP) confines high-density plasma to a plasma generation space adjacent to a plasma processing space. JP-A-4-29042, which is the same as that of the first embodiment, except that the plasma generation space is adjacent to the plasma processing space.
No. 8, such as the one described in Japanese Patent Application Laid-Open No. 8 (1999), confine high-density plasma using circularly polarized electromagnetic waves from a ring antenna.

Further, it is difficult to uniformly supply plasma in a single plasma generation space with the enlargement of a processing target such as a liquid crystal substrate and expansion of a plasma processing space. In some cases, a plurality of plasma generating spaces are provided. In this case, each of the plasma generation spaces is provided with a control valve,
The processing gas is introduced and supplied. In addition, the plasma generation space is divided into vertical cylindrical spaces so that the opening area does not decrease even if it is divided into multiple spaces, each side is surrounded by a high-frequency coil for excitation, and the magnetism for sealing the plasma is formed by a cylinder. It is also fed from the upper and lower end faces.

[0005] In any case, the exhaust of the treated gas, that is, the exhaust, is performed by suctioning a portion connected to the greatly opened side portion and peripheral portion of the plasma processing space by a vacuum pump. Exhaust is performed from the open peripheral portion between the parallel plates at the edge of the flat plate that cannot be covered by the parallel plates, or from the open side surface of the plasma processing space between the plasma generation space and the workpiece,
No exhaust was performed from the place where the parallel plate or the plasma generation space was placed.

[0006]

However, when exhausting air from the open side of the plasma processing space, the distance between the central portion and the peripheral portion of the plasma processing space until the air is exhausted is different. The by-product gas generated by the plasma processing, in particular, the processed gas from the surface of the object to be processed is discharged relatively quickly in the peripheral portion of the plasma processing space,
In the central part of the plasma processing space, it tends to stay for a long time and its concentration tends to be high. In addition, the presence of such a reaction product gas may hinder the desired plasma reaction or cause an undesirable secondary reaction. For this reason, even if the plasma density and the processing gas supply concentration are made uniform, there is a limit to the uniformity of the plasma processing on the surface of the processing object.

On the other hand, the substrates and the like have become much larger with the increase in the degree of integration of ICs and the size of display panels, and the demand for plasma processing apparatuses for processing such substrates has been increasing. This does not mean that the demand for uniform processing is relaxed. Rather, it is necessary to improve the uniformity of the plasma treatment regardless of whether the size is large or the same size. Therefore, in order to meet such a demand, it is an issue how to exhaust the treated gas from the plasma processing space without unevenness.

The present invention has been made to solve such a problem, and has as its object to realize a plasma processing apparatus capable of performing plasma processing uniformly.

[0009]

The first to fifth solving means invented to solve such a problem are as follows.
The configuration and operation and effect will be described below.

[First Solution] A plasma processing apparatus according to a first solution (as described in claim 1 at the beginning of the application) comprises a pair of opposed flat plates each having a processing gas supply port formed in one flat plate. In a plasma processing apparatus for performing plasma processing by forming a plasma processing space between parallel flat plates, an exhaust path having an exhaust port opened toward the plasma processing space is formed in the one flat plate (and an adjacent mechanism). It is characterized by having been done.

[0011] In the plasma processing apparatus of the first solution, the processed gas containing an undesired component secondaryly generated from the surface or the like of the object to be processed by the plasma processing is subjected to plasma processing. The gas enters the exhaust port from the processing space and is further discharged through the exhaust path.However, since the exhaust port is formed on one flat plate and the exhaust is performed from the place where the parallel plate is placed, it is generated at the center of the plasma processing space. Even the extracted component is quickly discharged without moving a long distance to the peripheral portion of the plasma processing space.

[0012] This reduces the difference between the central portion and the peripheral portion of the plasma processing space with respect to the moving distance until the processed gas is exhausted, so that the processed gas is exhausted from the plasma processing space without unevenness. Therefore, the concentration distribution of the processed gas in the plasma processing space also approaches a uniform state. Therefore, according to the present invention, it is possible to realize a plasma processing apparatus capable of performing more uniform plasma processing beyond the uniformity obtained by the uniform supply of the processing gas.

[Second Solution] A plasma processing apparatus according to a second solution (as described in claim 2 at the beginning of the application) comprises a first mechanism in which a plasma processing space is formed, and the first mechanism. A plasma generating space, wherein the plasma generating space is adjacent to and communicates with the plasma processing space. An exhaust path having an exhaust port opened toward the processing space is formed in the second mechanism.

[0014] In the plasma processing apparatus according to the second solution, the processed gas containing an undesired component secondaryly generated from the surface or the like of the object to be processed by the plasma processing is a plasma processing apparatus. The gas enters the exhaust port from the processing space, and is further discharged through the exhaust path. However, since the exhaust port is formed in the second mechanism and the exhaust is performed from the place where the plasma generation space is placed, the central portion of the plasma processing space is used. Even the generated components are quickly discharged without moving a long distance to the peripheral portion of the plasma processing space.

[0015] This reduces the difference between the central portion and the peripheral portion of the plasma processing space with respect to the moving distance until the processed gas is exhausted, so that the processed gas is exhausted from the plasma processing space without unevenness. Therefore, the concentration distribution of the processed gas in the plasma processing space also approaches a uniform state. Therefore, according to the present invention, it is possible to realize a plasma processing apparatus capable of performing plasma processing more uniformly than the uniformity obtained by uniform supply of plasma.

[Third Solution] The plasma processing apparatus of the third solution (as described in claim 3 at the beginning of the application) is the plasma processing apparatus of the first and second solutions. The exhaust ports are formed in a dispersed manner.

Here, the above “dispersion etc.” means, in addition to the literal dispersal of being scattered in a point-like manner, and the case of being divided so as not to be close to each other,
When a plurality, or a mixture thereof, of a linear shape, a broken line shape, a straight shape, a curved shape, or the like is distributed in an adjacent portion or a communicating portion with the plasma processing space, further, a ring shape, a circular shape, a polygon shape, a spiral shape It is also applicable that many of them are concentrically or non-concentrically arranged in a row or formed independently and widely.

In the plasma processing apparatus according to the third solution, most of the processed gas is quickly discharged from the exhaust port near where the processed gas is generated. Thereby, there is almost no difference in the moving distance until the treated gas is exhausted over substantially the entire plasma processing space, so that the concentration distribution of the treated gas in the plasma processing space approaches a more uniform state. Therefore,
According to the present invention, a plasma processing apparatus capable of performing plasma processing more uniformly can be realized.

[Fourth Solution] The plasma processing apparatus of the fourth solution (as described in claim 4 at the beginning of the application) is the plasma processing apparatus of the first to third solutions. Further, a porous insulating member is loaded in the exhaust passage near or at the exhaust port.

In the plasma processing apparatus according to the fourth solution, the plasma that has jumped into the exhaust port opened in the plasma processing space is discharged through the pores of the porous insulating member. You. Moreover, in such pores, it is difficult to maintain a plasma state due to a short mean free path of atoms and the like, and the gas quickly becomes a normal gas.

This eliminates the possibility that the exhaust path is contaminated by the plasma and that the contaminants do not flow back into the plasma processing space, so that the exhaust port and the exhaust path can be formed sufficiently wide. The design and processing of arranging the exhaust port and the exhaust path so as to accurately cancel the unevenness of the gas concentration are also facilitated. Therefore, according to the present invention,
A plasma processing apparatus capable of performing plasma processing uniformly can be easily realized.

[Fifth Solution Means] The plasma processing apparatus of the fifth solution means (as described in claim 5 at the beginning of the application) is the plasma processing apparatus of the first solution means, Among the processing gas supply ports, those positioned on both sides of the exhaust port are inclined (formed) so as to expand (when viewed along an extension line into the plasma processing space). .

In the plasma processing apparatus according to the fifth solution, since the processing gas is sent so as to spread into the plasma processing space, there is little space between the processing gas supply ports, that is, the exhaust port. However, since the pressure of the air pocket wind is relatively low, the processed gas from the object to be processed is diffused toward the exhaust port without being obstructed by the flow of the processing gas. Exhaust gas is discharged quickly even in places other than the peripheral part of the plasma processing space.

Thus, even if the exhaust port and the exhaust path are the same, the exhaust capacity is enhanced, and the design and processing of arranging the exhaust port and the exhaust path so as to accurately cancel the unevenness in the concentration of the processed gas are facilitated. Therefore, according to the present invention, a plasma processing apparatus that can perform plasma processing uniformly can be easily realized.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The plasma processing apparatus of the present invention achieved by such a solution is generally used by being mounted on an appropriate vacuum chamber. For this purpose, each mechanism such as a first mechanism in which the plasma processing space is formed and a second mechanism in which the plasma generation space is formed, or a parallel plate of the parallel plate in which the plasma generation space adjacent to the plasma processing space is formed. Each of the mechanical parts, such as one of the flat plates and its adjacent mechanism, is separately formed and then attached from the viewpoint of, for example, balancing the ease of incorporation into the vacuum chamber and the necessity of the degree of vacuum. In many cases, for example, they are often fixedly attached to each other, but may be integrally formed by processing a part or all of the same or single member such as a clad material.

Hereinafter, embodiments of the present invention will be described in detail with reference to first to third embodiments. The first embodiment embodies the above-described first to fourth solving means. The second embodiment also embodies the fifth solving means described above. In addition, while these use a square substrate as an object to be processed, the third embodiment uses a round substrate as an object to be processed.

[0027]

First Embodiment A specific structure of a plasma etcher as a first embodiment of the plasma processing apparatus of the present invention will be described with reference to the drawings. FIG. 1 is a plan view and a longitudinal sectional view around the plasma space, and FIG.
FIG. 3 is a vertical cross-sectional perspective view around the plasma generation space, and FIG.
4 is an enlarged view of one of the plasma generation spaces, FIG. 4 is an enlarged view of one of the exhaust chambers, and FIG. 5 is a cross-sectional view of the entire apparatus including the vacuum chamber.

This plasma etcher includes a first mechanism for securing a plasma processing space, a second mechanism for securing a plasma generation space and an additional portion thereof, and an application mechanism for applying an electric field or a magnetic field to each plasma. And a circuit section. In order to process a square workpiece 1 such as a liquid crystal substrate, both the first mechanism and the second mechanism are formed substantially in a substantially rectangular shape (see FIG. 1A).

The first mechanism has an anode portion 11 and a cathode portion 12, both of which are a pair of parallel flat plates opposed to each other and made of metal. The anode portion 11 is disposed above and an object to be processed such as a liquid crystal substrate. 1 is mounted on the lower side, and a cathode processing section 13 for the low-temperature plasma 10 is interposed between the cathode section 12 and the cathode processing section 13.
Is formed. Also, the anode part 11
In FIG. 1, a large number of communication ports 14 penetrate and are drilled in advance, and a large number of processing gas supply ports 15 opened toward the plasma processing space 13 are formed (FIG. 1).
(B), see longitudinal sections in FIGS. 2 and 3). In this example, the ratio of the cross-sectional area of the communication port 14 to the effective cross-sectional area of the plasma processing space 13, that is, the first ratio is 0.05. The plasma processing space 13 is supplied via the processing gas supply port 15.
As the processing gas B supplied to the reactor, a gas obtained by mixing an appropriate amount of a diluting gas with a reactive gas such as a CF-based gas or a silane gas is supplied.

The second mechanism is mainly composed of a plasma generation chamber 21 made of an insulator such as a ceramic. The plasma generation chamber 21 has a plurality of plasma generation spaces 22 (4 in FIG. 1A). ) Straight grooves are engraved in parallel. Thereby, the plasma generation space 22 is linear. The plasma generation chamber 21 is fixedly mounted with the opening side (the lower surface in the longitudinal sectional view) of the plasma generation space 22 in close contact with the upper surface of the anode section 11. At this time, the positioning is performed so that the opening of the plasma generation space 22 overlaps the communication port 14 of the anode unit 11. Thereby, the plasma generation space 22
And the plasma processing space 13 are adjacent to and communicate with each other, and the plasma generating space 22 extends linearly along the surface adjacent to the plasma processing space 13. In this example, the ratio of the cross-sectional area of the communication port 14 to the cross-sectional area of the plasma generation space 22, that is, the second ratio is 0.5. The values of these ratios can be freely changed as long as the magnitude relation is not reversed.

In the plasma generation chamber 21, a plasma gas supply path 23 is also formed in a straight line by a gas distribution member 21a attached deeper (upward in the longitudinal sectional view) of the plasma generation space 22, Both are communicated by a large number of small holes, and the plasma generation space 22 receives the supply of the plasma generation gas A from the bottom (the upper side in the vertical sectional view) to generate the high-density plasma 20 and performs the plasma processing through the communication port 14. It is sent to the space 13. An inert gas that does not react chemically, such as argon, is used as the plasma generation gas A.

Further, in the plasma generation chamber 21, a back surface (an upper surface in a longitudinal sectional view) on the opening side of the plasma generation space 22 is cut off so as to leave a side wall and a bottom portion surrounding the plasma generation space 22. Then, the one permanent magnet 25 (the lower part in the longitudinal sectional view), the coil 24 and the other permanent magnet 25 (the upper part in the longitudinal sectional view) are sequentially stacked and packed therein. Each of the permanent magnets 25 has a rod shape and is cut to have substantially the same length as the plasma generation space 22 (see FIG. 1A). In addition, a pair of permanent magnets 25 and coils 24 are added to both side walls of each plasma generation space 22 so that all the plasma generation spaces 22 are
It is sandwiched by 5. Thereby, the magnetic member 25 is provided on the second mechanism side and attached to the plasma generation space 22, and linearly extends together with the plasma generation space 22 along the adjacent surface between the plasma generation space 22 and the plasma processing space 13. It has become something.

The permanent magnet 25 has a height obtained by adding the coil 24 to the pair and is substantially equal to that of the plasma generation space 22, and the magnetic poles are oriented in the direction of the horizontal plasma generation space 22 (vertical section in FIG. 3). Face). More specifically, the magnetic flux lines 26 extending laterally from the lower half of the permanent magnet 25 in the upper part of the figure pass near the coil 24 and return to the opposite side in the figure. There is a magnetic peak with the top at approximately the lower end of 25. A substantially similar magnetic peak is formed at the upper end of the permanent magnet 25 in the lower part of the figure. Since the permanent magnets 25 are provided on both sides of the plasma generation space 22, four magnetic peaks are formed around the plasma generation space 22. Therefore, a so-called magnetic basin surrounded by magnetic peaks is formed in the plasma generation space 22. Then, the electrons are captured here. The potential field wind has been described. However, since it is actually a vector field, it is complicated to describe precisely. In short, however, electrons are sealed in a rod shape in the columnar / beam-like plasma generation space 22 as a whole. is there.

Further, the surface of the plasma generation chamber 21 opposite to the anode portion 11 (the upper surface in the longitudinal section of FIGS. 1 and 2).
On the other hand, between the parallel running plasma generating space 22 and the space between the coil 24 and the permanent magnet 25 provided respectively (see FIGS. 1 and 2), a hollow exhaust surrounding member 27 is provided. Is attached. Each of the exhaust surrounding members 27 has substantially the same length as that of the plasma generating space 22 (see FIG. 1A), both ends are closed, and the hollow is an exhaust reservoir 28 which is a part of the exhaust passage. . The exhaust surrounding member 27 and the anode portion 11 are formed with a large number of exhaust holes 16 that penetrate them and communicate the exhaust reservoir 28 and the plasma processing space 13 (see FIGS. 1 and 2).

The exhaust surrounding member 27 is connected to the exhaust port 16.
On the opposite side (the upper part in FIG. 2), an external pipe communicating with the exhaust reservoir 28 is connected. The external pipe has a variable throttle valve 6 for adjusting the exhaust flow rate and a source of the suction / discharge force. A vacuum pump 7 for generating a vacuum pressure is also connected (see FIG. 5). Thereby, the exhaust port 16, the exhaust reservoir 28,
The variable throttle valve 6, the vacuum pump 7, and a path connecting them are an exhaust path having an exhaust port 16 opened toward the plasma processing space 13.
And the second mechanism 21.

In addition, the direction of the magnetic pole of the permanent magnet 25 sandwiching the exhaust reservoir 28 is reversed from that of the permanent magnet 25 with respect to the plasma generating space 22 so that plasma is not induced (see FIG. 4). A porous insulating member made of ceramic or resin is loaded in the portion on the exhaust port 16 side (the lower half in FIG. 4). The outer pipe (upper half in FIG. 4) of the exhaust reservoir 28 that is remote from the exhaust port 16 is open in order to equalize the vacuum pressure and uniformly exhaust the air from each exhaust port 16. . As a result, a porous insulating member is loaded near the exhaust port 16 in the exhaust path 28 described above.

The application circuit section is divided into a first application circuit centered on the RF power supply 31 and a second application circuit centered on the RF power supply 32. The output power of the RF power supply 31 is variable. The output of the RF power supply 31 is supplied to the cathode section 12 via a blocking capacitor in order to apply an alternating electric field to the grounded anode section and generate a bias voltage. Will be sent. This also includes a frequency of 500
A frequency of KHz to 2 MHz is often used. Thus, the first application circuit applies an electric field that contributes to the low-temperature plasma 10 to some extent to the plasma processing space 13. The RF power source 32 also has a variable output power, and drives both coils 24 sandwiching the plasma generation space 22 to apply an alternating magnetic field to the plasma generation space 22. Its maximum output power is large,
The frequency is often 13 MHz to 100 MHz. Thereby, the second application circuit is provided with the high-density plasma 2
A magnetic field that contributes to generation and enhancement of zero is applied to the plasma generation space 22.

Each of these components is mounted directly or indirectly on the vacuum chamber to complete a plasma processing apparatus. That is, the cathode section 12 on which the object 1 is placed
Is installed in the center of a box-shaped vacuum chamber main body 2 having an open top. The vacuum chamber main body 2 has a vacuum chamber lid 3 attached to the top so as to be openable and closable, and a vacuum at the bottom or side. A vacuum pump 5 such as a turbo pump is connected via a variable valve 4 for pressure control. Vacuum chamber lid 3
The plasma generation chamber 21 and the anode section 11 are attached, and water cooling is also possible. When this is closed, the inside of the vacuum chamber main body 2 and further the plasma processing space 13 and the plasma generation space 22 are sealed. As a result, the plasma processing apparatus mainly has an exhaust path via the variable valve 4 and the vacuum pump 5 for exhausting from the peripheral portion of the plasma processing space 13, and exhausts from the anode section 11 and the plasma generation space 22. The exhaust gas is exhausted through the exhaust port 16, the exhaust reservoir 28, the variable throttle valve 6, and the exhaust path via the vacuum pump 7.

Regarding the plasma processing apparatus of this embodiment,
The mode of use and operation will be described with reference to the drawings. 6A and 6B are explanatory diagrams of the operation. FIG.
(B) is for the above-described plasma etcher in which the exhaust path 28 is formed on the anode section 11 side, while the apparatus has no exhaust path 28 on the side.

When the vacuum pump 5 and the vacuum pump 7 are operated and the supply of the plasma gas A and the supply of the processing gas B through the processing gas supply port 15 are appropriately started, the vacuum pump 5 is mounted on the cathode section 12. The preparation for the plasma processing for the processed object 1 is completed. Specifically, the plasma processing space 13 and the plasma generation space 22 are maintained at a vacuum pressure suitable for plasma processing mainly by exhausting the vacuum pump 5. Further, the plasma gas A is supplied to the respective plasma generation spaces 22 through the plasma gas supply path 23.
Will be introduced. The processing gas B has a large number of processing gas supply ports 1
After being divided into five, they are introduced into the plasma processing space 13.

Then, when the RF power source 32 is also operated,
An RF electromagnetic field is applied to the plasma generation space 22 via the coil 24, and the electrons of the plasma gas A in the plasma generation space 22 are vigorously moved. At this time, the electrons stay in the plasma generating space 22 for a long time due to the action of the magnetic circuit by the permanent magnet pieces 25, fly around while spiraling in the annular space, and excite the plasma gas A. Thus, high-density plasma is generated in the plasma generation space 22. The high-density plasma has a high energy of 10 to 15 eV or more, which greatly contributes to generation of ion species, in the electrons sealed in the plasma generation space 22. Become.
The high-density plasma expanded in the plasma generation space 22, particularly, its radical species and ionic species components are rapidly transferred to the plasma processing space 13 through the communication port 14 by the expansion pressure.

Further, when the RF power supply 31 is also operated, an RF electric field is applied to the plasma processing space 13 via the anode unit 11 and the cathode unit 12. Since there is no magnetic circuit or the like for confining electrons, even if the processing gas B or the like is excited, high-density plasma cannot be generated, and the low-temperature plasma remains. When only the power from the RF power source 31 is used, the low-temperature plasma 10 has a small amount of electrons having energy of 10 to 15 eV or more, so that the ratio of radical species components increases. However, in the case of low-temperature plasma in this apparatus, since the above-described high-density plasma is mixed, the actual ratio between the radical species component and the ion species component is determined by the RF power source 3.
Depending on the output ratio of 1, 32, etc., it will be any ratio between the two.

Then, the ratio between the radical species component and the ion species component in the low-temperature plasma in the plasma processing space is variably controlled, and if the etching process proceeds efficiently under the optimum conditions for the etching at that time, the low-temperature plasma The by-product gas 10a contained in 10 increases. Since the by-product gas 10a mainly comes out of the object to be processed 1, the by-product gas 10a becomes thicker immediately above the cathode portion 12. In addition, the center of the cathode 12 tends to be darker. Such a concentration distribution remains even if the high-density plasma 20 and the processing gas supply port 15 are dispersed and then introduced into the low-temperature plasma 10 (see FIG. 6A). Exhaust port 16 and exhaust reservoir 28
In the case of this plasma etcher, which is also distributed,
The by-product gas 10a is quickly discharged from the exhaust port 16 nearby to the exhaust reservoir 28 and thereafter (see FIG. 6B).

Since the discharge effect is greater in the central portion and the middle portion of the cathode portion 12 where the concentration of the by-product gas 10a is high, the concentration distribution of the by-product gas 10a is reduced in variation and approaches a uniform distribution. . In addition, the by-product gas 10a becomes uniform in a preferable state in which the concentration of the by-product gas 10a becomes low as a whole. In this manner, the plasma processing on the processing target 1 is performed more uniformly.

Further, with the exhaust through the exhaust port 16,
Some of the low-temperature plasma 10 may enter the exhaust port 16 and further reach the exhaust reservoir 28, but they may reach the porous insulating member in the exhaust reservoir 28 and lose energy when colliding therewith. As a result, the plasma state cannot be maintained, and the state returns to the normal gas state. In this way, even if the gas is exhausted from a position facing the central portion or the intermediate portion of the low-temperature plasma 10, the exhaust can be efficiently performed, and high-quality plasma is maintained.

Moreover, since the plasma generating spaces 22 and the exhaust chambers 28 are alternately arranged, no matter how large the object 1 and thus the plasma processing space 13 become, the number of these 22, 22 can be easily increased. In addition, uniformity of the plasma processing can be ensured.

[0047]

Second Embodiment FIG. 7 is a longitudinal sectional perspective view showing the vicinity of a plasma generation space. The second embodiment differs from the second embodiment shown in FIG. The processing gas supply port 15a located on the right side of FIG. 2 is formed obliquely from the upper left to the lower right, and the processing gas supply port 15b located on the left side of the exhaust port 16 in the figure is inclined from the upper right to the lower left. This is a point that is formed inclined. As a result, the processing gas supply ports 15a and 15b located on both sides of the exhaust port 16 of the processing gas supply port 15 are inclined in such a manner as to expand when viewed along the extension line into the plasma processing space 13. It has been formed.

In contrast, in the case of the first embodiment in which all the processing gas supply ports 15 are vertical (see FIG. 8A), the processing gas A sent to the low-temperature plasma 10 There is also a small amount of gas that is not put into the low-temperature plasma 10 and contributes to the plasma processing without being contributing to the plasma processing, and is immediately discharged in a U-turn toward the exhaust reservoir 28 to some extent. The diffusion of
It may be partially pushed back.

On the other hand, in the case of the second embodiment (FIG. 8)
(B)), inclined processing gas supply ports 15a, 15b
Most of the processing gas A sent obliquely toward the low-temperature plasma 10 enters the low-temperature plasma 10 in such a manner that most of the processing gas A leaves the exhaust port 16 and is dragged by the high-density plasma from the communication port 14. Contributes to plasma processing. As a result, the by-product gas 10a is diffused to a place where there is no obstruction, and consequently the exhaust gas 16 is quickly discharged toward the exhaust port 16. In this way, the plasma processing on the processing target 1 is performed more uniformly and efficiently.

[0050]

Third Embodiment A third embodiment of the plasma processing apparatus according to the present invention, which is a plan view showing the vicinity of the plasma generation space in FIG. 9, will be described. This is different from the first and second embodiments described above in that the plasma generation chamber 21 and the like are formed in a disk shape for plasma processing a round IC wafer, and the plasma generation space 22 and permanent magnet 25
And the exhaust surrounding member 27 is provided in the center of the plasma generation chamber 21 in a shape that is not a bar but a shape close to a point. Is a point.

In this case, the by-product gas in the central portion, which tends to be the thickest, can be efficiently exhausted, and the uniformity of the plasma processing is improved. That is, as for the plasma generation space 22, a plurality of plasma generation spaces and magnetic members attached thereto are linearly provided along the adjacent surface to the plasma processing space, and are alternately arranged and run in parallel. Is what it is. By devising the shape and arrangement of the plasma generation space and the magnetic member, the cross-sectional area ratio between the plasma generation space and the plasma processing space changes, and the magnetic member is processed and processed.
By making mounting easier, it is possible to realize a plasma generator that supplies high-quality plasma by preventing gas from flowing from the plasma processing space to the plasma generation space and that is easy to manufacture. In addition, the effective use of the magnetic member and the fact that the plasma generation spaces can be arranged densely allow the mounting and manufacturing to be further facilitated.

[0052]

As is apparent from the above description, in the plasma processing apparatus according to the first aspect of the present invention, the moving distance until the processed gas is exhausted is set at the center of the plasma processing space. By reducing the difference between the peripheral portion and the peripheral portion, there is an advantageous effect that a plasma processing apparatus capable of performing plasma processing more uniformly than the uniformity obtained by the uniform supply of the processing gas can be realized. Yes.

Further, in the plasma processing apparatus according to the second solution of the present invention, the difference between the central portion and the peripheral portion of the plasma processing space with respect to the moving distance until the processed gas is exhausted is reduced. This has an advantageous effect that a plasma processing apparatus capable of performing plasma processing more uniformly than the uniformity obtained by uniform supply of plasma can be realized.

Further, in the plasma processing apparatus according to the third solution of the present invention, there is almost no difference in the moving distance until the processed gas is exhausted over substantially the entire plasma processing space. This has an advantageous effect that a plasma processing apparatus capable of performing plasma processing more uniformly can be realized.

In the plasma processing apparatus according to the fourth solution of the present invention, since the exhaust path is not contaminated by plasma, a plasma processing apparatus capable of uniformly performing plasma processing can be easily realized. It has the advantageous effect of becoming.

Further, in the plasma processing apparatus according to the fifth solution of the present invention, the plasma processing apparatus can uniformly perform the plasma processing by increasing the exhaust capacity even if the exhaust port and the exhaust path are the same. Is easily realized.

[Brief description of the drawings]

FIG. 1A is a plan view and FIG. 1B is a longitudinal sectional view around a plasma space in a plasma etcher as a first embodiment of the plasma processing apparatus of the present invention.

FIG. 2 is a vertical cross-sectional perspective view around the plasma generation space.

FIG. 3 is an enlarged view of one of the plasma generation spaces.

FIG. 4 is an enlarged view of one of the exhaust pools.

FIG. 5 is an overall cross-sectional view including a vacuum chamber.

FIG. 6 is an explanatory diagram of the operation.

FIG. 7 is a vertical cross-sectional perspective view around a plasma generation space of a second embodiment of the plasma processing apparatus of the present invention.

FIG. 8 is an explanatory diagram of the operation.

FIG. 9 is a plan view around a plasma generation space of a third embodiment of the plasma processing apparatus of the present invention.

[Explanation of symbols]

Reference Signs List 1 workpiece 2 vacuum chamber main body 3 vacuum chamber lid 4 variable valve (pressure control mechanism, exhaust means) 5 vacuum pump (vacuum pressure generation source, exhaust means) 6 variable throttle valve (flow rate adjustment mechanism, exhaust path, exhaust) Means 7 Vacuum pump (vacuum pressure generation source, exhaust path, exhaust means) 10 Low temperature plasma 10a By-product gas 11 Anode unit (one of parallel plates, first mechanism, first application circuit) 12 Cathode unit (the other of parallel plates) , First mechanism, first application circuit) 13 plasma processing space (low-temperature plasma space) 14 communication port 15 processing gas supply port 15a, 15b inclined processing gas supply port 16 exhaust port (processed gas discharge path, exhaust path, exhaust) Means) 20 High density plasma 21 Plasma generation chamber (adjacent mechanism, second mechanism) 21a Gas distribution member (second mechanism) 22 Plasma generation space (high density plasma) 23) Gas supply path for plasma (non-reactive gas supply path) 24 Coil (second application circuit) 25 Permanent magnet (magnetic member for magnetic circuit) 26 Magnetic flux line (magnetic circuit) 27 Exhaust surrounding member (Adjacent mechanism, second mechanism, exhaust path, exhaust means) 28 Exhaust reservoir (processed gas exhaust path, exhaust path, exhaust means) 29 Porous insulating member 31 RF power supply (first application circuit) 32 RF power supply (second Application circuit) A Argon gas (non-reactive gas, gas for plasma generation) B CF-based gas (reactive gas, processing gas) C Exhaust (suction exhaust gas)

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI // H01L 21/31 H01L 21/302 C (72) Inventor Toshihisa Nozawa 1-5-5 Takatsukadai, Nishi-ku, Kobe-shi, Hyogo Kobe Steel, Ltd.Kobe Research Institute (72) Inventor Kiyotaka Ishibashi 1-5-5 Takatsukadai, Nishi-ku, Kobe City, Hyogo Prefecture Kobe Steel Research Institute, Kobe Research Institute

Claims (5)

[Claims] 1. A plasma processing apparatus for performing plasma processing by forming a plasma processing space between a pair of opposed parallel flat plates having a processing gas supply port formed in one flat plate, wherein the plasma processing space is directed toward the plasma processing space. An exhaust path having an exhaust port is formed on the one flat plate. 2. A plasma generating space comprising: a first mechanism having a plasma processing space formed therein; and a second mechanism having a plasma generating space formed by being attached to or integral with the first mechanism. A plasma processing apparatus, wherein a space is adjacent to and communicates with the plasma processing space, wherein an exhaust path having an exhaust port opened toward the plasma processing space is formed in the second mechanism. apparatus. 3. The plasma processing apparatus according to claim 1, wherein the exhaust ports are formed in a dispersed manner. 4. The plasma according to claim 1, wherein a porous insulating member is mounted in the exhaust passage near or at all of the exhaust port. Processing equipment. 5. The plasma processing apparatus according to claim 1, wherein the processing gas supply ports located on both sides of the exhaust port are inclined so as to expand.