JP2000357683A - Plasma treatment method and apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To uniformly treat in a substrate surface, in a plasma treatment of large-aperture substrates by correcting the off centering of the plasma density distribution to uniformly distribute it in a chamber of a plasma treatment apparatus for forming a plasma with electromagnetic waves fed into the chamber. SOLUTION: This plasma treatment apparatus, which feeds electromagnetic waves to a first plate to generate a plasma in a vacuum atmosphere between the first plate and a second plate facing the first plate, thereby treating a substrate laid on the second plate, comprises a dielectric window 12 for propagating the electromagnetic waves at the periphery of the first plate and an electric conductor- or dielectric-made electromagnetic wave distributing correction body 14 buried in the window 12 apart from the first plate not, so as to expose at least the side face and bottom face of the correction body 14 to the vacuum atmosphere.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an etching apparatus or a CVD apparatus using plasma, and relates to processing a sample such as a semiconductor element substrate or a liquid crystal substrate using a gas dissociated by plasma. The present invention relates to a plasma processing apparatus suitable for controlling distribution of a processing speed in a substrate, and a plasma processing method for processing a substrate surface using the apparatus.

[0002]

2. Description of the Related Art In a conventional plasma processing apparatus, for example, an electromagnetic wave is introduced into a chamber through a microwave introduction window, and a magnetic field is separately formed in a processing chamber to generate plasma.

In a conventional microwave plasma generating apparatus, for example, in a microwave plasma apparatus as disclosed in Japanese Patent Application Laid-Open No. 5-263274, plasma is diffused by increasing the distance between a microwave introduction window and a substrate. By doing so, the plasma distribution on the substrate, particularly the ion flux distribution, has been made uniform. Furthermore, Japanese Patent Application Laid-Open
In Japanese Patent No. 104210, by disposing a plurality of dielectrics in a processing chamber and distributing a microwave incident from a window between the dielectrics, the distribution of radicals generated by the microwave is uniformly distributed in the processing chamber. It was devised to become.

Further, in Japanese Patent Application Laid-Open No. 6-104210, a shielding plate for shielding a plasma reaction chamber from a microwave plasma generation chamber is provided between these chambers, and these chambers are communicated with each other through pores. . In addition, JP-A-7-
In Japanese Patent No. 263348, a plurality of dielectric pieces are arranged on a microwave incident surface of a microwave introduction window member that separates a plasma generation chamber and a microwave introduction unit, and a microwave intensity distribution radiated into the plasma generation chamber is controlled. I was trying to do it. Further, in Japanese Patent Application Laid-Open No. 9-148097, a dielectric window for isolating an electromagnetic wave transmission unit and a discharge chamber is provided in the electromagnetic wave transmission unit, an electromagnetic wave reflection plate is provided on the discharge chamber side of the dielectric window, and a ring-shaped plasma is provided in the discharge chamber. Was generated.

[0005]

SUMMARY OF THE INVENTION Recent semiconductor memories,
For example, 256MDRAM (Dynamic Random Access Memor)
The y) and later devices, for fine contact hole formation and the like, increase the SiO ₂ / SiN selection ratio of SiO ₂ film etching, for example, be more than 20 are required. On the other hand, the diameter of a substrate (wafer) used for manufacturing a semiconductor memory is increasing year by year, and for example, a substrate having a diameter of 300 mm is being adopted. When plasma treatment is performed on such a large-diameter substrate, it is important to ensure uniformity of plasma in the radial direction.

As a plasma processing apparatus, for example, 450 MHz
Those that generate plasma with the electromagnetic wave of z include, for example, 2.
Compared with the case of the electromagnetic wave of 45 GHz, the electromagnetic wave propagates in the plasma under the condition of 29 times higher electron density and 5.4 times higher pressure according to the theory of electromagnetic wave propagation in plasma. On the other hand, the higher the density and pressure, the greater the attenuation (absorption) of the electromagnetic waves in the plasma. Therefore, when the electromagnetic wave of 450 MHz enters the plasma, it attenuates immediately before reaching the ECR surface. Also, an attenuated electric field exists in a magnetic field region lower than the ECR surface. Thus, the electromagnetic wave is absorbed in the plasma near the sheath immediately below the antenna. An electric field having a center height is generated, and a medium-high power deposition, and as a result, a medium-high electron density distribution is obtained.

In the above prior art, when the height of the chamber is reduced, if the power is low, the plasma concentrated at the center as a whole does not sufficiently diffuse to the periphery, so that the ion flux to the substrate decreases as the outer periphery. Occurred. Also,
In an apparatus with a structure in which an electrode for applying a bias voltage is placed on the wall (quartz window) facing the substrate, depending on the conditions of the magnetic field, the microwave concentrates below the electrode, and the generated plasma density has a radius. There was a problem that the directions became non-uniform.

In a microwave plasma processing apparatus, a member for absorbing or reflecting microwaves is fixedly provided in a waveguide, and the microwave is generated in the plasma generation chamber and re-entered after being irregularly reflected. And a structure in which a plurality of dielectric pieces are arranged on the microwave incident surface of the window to control the microwave intensity distribution radiated into the plasma generation chamber, Alternatively, a structure in which an electromagnetic wave reflecting plate is provided on the discharge chamber side of the microwave introduction window material has been proposed, but when applied to a structure having an electrode in the center, the electromagnetic wave reflecting plate or a dielectric piece has an electrode surface in the center. Away from the structure, or
The structure is separated from the plasma, and there is a problem that the effect of increasing the electric field near the outer periphery of the electrode is small. Also, if the electromagnetic wave reflecting plate or the dielectric piece is in direct contact with the plasma, depending on the type of gas, the electromagnetic wave concentrates at those corners and locally strong plasma is generated, and the electromagnetic wave reflecting plate or the dielectric piece Has been consumed, and the abrasion has scattered to contaminate the substrate.

An object of the present invention is to provide a plasma processing apparatus for forming a plasma by introducing an electromagnetic wave into a chamber.
A plasma processing apparatus and a plasma processing apparatus, which correct a bias of a plasma density distribution toward a central portion, uniformly distribute the plasma in a chamber, and perform a uniform processing in a substrate surface when performing a plasma processing on a substrate having a large diameter. It is to provide a processing method.

[0010]

In order to solve the above-mentioned problems, the present invention provides an electromagnetic wave supplied to a first plate and evacuated to a vacuum atmosphere between the first plate and a second plate disposed opposite to the first plate. In a plasma processing apparatus for generating plasma and processing a substrate placed on a second plate, a dielectric window for transmitting an electromagnetic wave is provided on an outer peripheral portion of the first plate, and the first window is provided in the window. An electromagnetic wave distribution corrector made of an electric conductor or a dielectric is buried separately from the plate such that at least the side surface and the lower surface of the magnetic wave distribution corrector are not exposed to the vacuum atmosphere.

Another feature of the present invention is that an electromagnetic wave is supplied to a first plate, and a plasma is generated in a vacuum atmosphere between the first plate and a second plate disposed opposite to the first plate. A plasma processing method for processing a substrate placed on the second plate, wherein the atmosphere in which the substrate is placed on the second plate is a vacuum atmosphere, and a step of introducing a gas into the vacuum atmosphere; An electromagnetic wave of 100 to 900 MHz is applied to the vacuum atmosphere through a dielectric window provided with an electric conductor or a dielectric electromagnetic wave distribution corrector made of an electric conductor or a dielectric provided inside the outer periphery of one plate and separated from the first plate inside. Introducing and generating a plasma; and
Etching a substrate provided on a plate; and removing the substrate from the vacuum atmosphere.

According to the present invention, the center of the electromagnetic wave is concentrated by inserting a substance that changes the dispersion of the electromagnetic wave, for example, a ring of a conductor into the window into which the electromagnetic wave near the outer diameter of the first plate is introduced. Can control the density distribution of the plasma in the radial direction.
A plasma processing apparatus and a plasma processing method capable of performing uniform processing in a substrate surface can be provided.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a sectional view of a plasma processing apparatus according to the method of the present invention. FIG. 2 is a detailed sectional view of the embodiment. 3 and 4 are conceptual diagrams showing the effects of the present embodiment. Here, an etching process will be described as an example.

In FIGS. 1 and 2, a substrate 4 is placed on a second plate 3 arranged inside a chamber 1 so as to face a first plate 2. The first plate 2 has 100 to 900 MHz,
For example, a coaxial cable 11 for supplying an electromagnetic wave of 450 MHz
Is connected to a 450 MHz power supply (not shown). The 450 MHz electromagnetic wave propagates between the chamber 1 and the coaxial cable 11, passes through the quartz block 12, and is introduced into the processing chamber 6. The space between the chamber 1 and the coaxial cable 11 may be filled with a dielectric 16 so that electromagnetic waves can easily propagate. The frequency of the electromagnetic wave is UH
A frequency such as an F band, a VHF band, a microwave band, or an RF band may be used.

An electromagnetic coil 13 is provided outside the chamber 1 to generate a magnetic field. The frequency of the electromagnetic wave is 300
In the case of 450 MHz out of ~ 600 MHz, the magnetic field strength is 0.0
Electron cyclotron resonance (ECR) occurs at 161 Tesla (161 Gauss). Thus, the plasma 7 is generated in the processing chamber 6 between the first plate 2 and the second plate 3,
The substrate 4 is processed. First plate 2 and second plate
RF is applied to each of the plates 3 so that a bias voltage is applied thereto.
(High frequency) auxiliary power supplies 5a and 5b are connected.

An electromagnetic coil 13 is provided outside the chamber 1 to generate a magnetic field. The frequency of the electromagnetic wave is 300
In the case of 450 MHz out of ~ 600 MHz, the magnetic field strength is 0.0
Electron cyclotron resonance (ECR) occurs at 161 Tesla (161 Gauss). Thus, the plasma 7 is generated in the processing chamber 6 between the first plate 2 and the second plate 3,
The substrate 4 is processed. First plate 2 and second plate
RF is applied to each of the plates 3 so that a bias voltage is applied thereto.
(High frequency) auxiliary power supplies 5a and 5b are connected. These auxiliary power supply 5a, the 5b, so the frequency is first plate 2 a high frequency power of 14MHz from 100kHz, to 8W / cm ² is applied from the second plate 3 and 0.5 W / cm ² per unit area on the substrate 4 ing.

A large number of gas holes 2a are formed in the center of the first plate 2, and are connected to gas supply means 8 to form a so-called shower head. Further, an exhaust port 9 is provided on the outer periphery of the second plate 3 and is evacuated by a vacuum pump (not shown). The first plate 2 is made of carbon, silicon, or the like.

As a plasma generating gas for etching, a mixed gas of argon and a fluorocarbon-based gas such as CF ₄ or C ₄ F ₈ , Cl ₂ , BCl ₃ , SF ₆ , HB
A gas such as r is properly used depending on the film to be etched.

In the above embodiment, in this embodiment,
It is characterized in that an electromagnetic wave distribution corrector 14 made of a conductor ring is arranged and fixed in an annular concave portion provided in the quartz block 12. FIG. 2 is a sectional view taken along line AA in FIG. The quartz block 12 may be formed integrally with the electromagnetic wave distribution corrector 14. However, since it is generally difficult to manufacture these integrally, it is preferable to divide the quartz block 12 into a plurality of parts, insert the electromagnetic wave distribution corrector 14, and assemble them together.

Here, the electromagnetic wave distribution corrector (conductor ring) 14 is in the form of a ring made of a conductor such as aluminum, copper, or iron. Is a floating state that is not electrically connected.

The quartz block 12 has a conductor ring 14
Does not need to be completely covered, and it is sufficient that the surface in contact with the plasma is covered with a quartz plate or the like so that the conductor ring 14 is not directly exposed to the plasma. That is, the thickness of the quartz inserted between the surface of the chamber and the conductor ring 14 is set to, for example, about 6 mm so that at least the side surface and the lower surface of the conductor ring 14 are not exposed to the plasma atmosphere. Various diameters of the first plate 2 are designed depending on the conditions to be used.
It is set smaller than twice. The conductor rings 14 are installed at an interval near the outer diameter of the first plate 2. This interval is, for example, about 10 mm. In many cases, the conductor ring 14 is installed beside the first plate 2. That is, the conductor ring 14 and the first plate 2 are set to have substantially the same axial height on the surface facing the plasma.

According to this embodiment, the electromagnetic wave propagates along the inside and outside of the conductor ring 14 which is an electromagnetic wave distribution corrector, in addition to the propagation toward the center along the first plate 2 as shown in FIG. Also propagates.

Here, a conventional plasma processing apparatus and a plasma processing apparatus having a conductor ring according to the present invention will be described.
A simulation was performed. The resulting UHF
FIG. 4 shows a contour map of the electric field intensity E _ab , power deposition, and electron density distribution. In the conventional type, an electric field having a center height is generated, and a medium-high power deposition, and as a result, a medium-high electron density distribution is obtained.

On the other hand, when a conductor ring is employed, an auxiliary electric field is held immediately below the conductor on the outer peripheral portion, a power deposit is added thereto, and a W-shaped electron density distribution is obtained, which has an effect of radial uniformity. From these results, the conductor ring is
It can be seen that the effect of increasing the outer periphery of the middle-high plasma distribution is high.

As described above, by employing the conductor ring, a strong electric field is maintained under the conductor ring 14 together with the electric field under the first plate 2. Therefore, as shown in FIG. 3, the auxiliary power deposition 15b is also provided under the conductor ring 14 similarly to the power deposition 15a at the center of the first plate 2.
Is performed, and the plasma is generated. Therefore, the outer peripheral portion of the plasma distribution which becomes maximum near the center is increased, and the plasma distribution is made uniform. The material of this ring may be a dielectric medium having a dielectric constant different from that of the quartz block 12. With this configuration, by selecting the dielectric constant of the conductor ring 14, there is an effect that the intensity of the electric field that can be held below the conductor ring 14 can be adjusted.

Therefore, according to the present invention, φ200 mm to 3 mm
A substrate having a large diameter of 50 mm can be plasma-processed uniformly in a plane.

The material of the conductor ring is not limited to a solid, but may be a liquid. As this liquid, for example,
Water or a refrigerant that also controls the temperature of the window may be used. With such a configuration, there is an effect that an apparatus having a uniform plasma distribution and little change over time can be provided. Also, in the case of a conductor, the inside may be empty only with the outer shell. With this configuration, it is possible to provide a lightweight plasma processing apparatus having a uniform plasma distribution.

Further, the conductor ring 14 and the first plate 2 or the chamber 1 may be connected by a wire via a switch (not shown). When the switch is turned on in such a configuration, the conductor ring 14 and the first plate 2 or the chamber 1 are electrically conducted to have the same potential. By controlling the intensity of the electric field formed below the conductor ring 14 by such an operation, the distribution of the plasma in the chamber can be arbitrarily controlled. In addition, such a conductor ring 1
4 may be provided in the radial direction. By changing the width and spacing of these conductor rings 14, there is an effect that the distribution of the intensity of the electric field held below the conductor rings 14 can be changed.

Next, FIG. 5 is a view showing another embodiment of the present invention.
Is thicker than the thickness of the first plate 2, and the lower surface of the conductor ring 14 whose upper surface is arranged at the same height as the upper surface of the first plate protrudes below the lower surface position of the first plate.

FIG. 6 is a view showing another embodiment of the present invention, in which the thickness of the electromagnetic wave distribution compensator, that is, the conductor ring 14 is thinner than the thickness of the first plate 2, so that the lower surface of the conductor ring 14 is It is retracted upward from the lower surface position of the first plate. When the lower surface of the conductor ring 14 protrudes downward as in the example of FIG. 5, the electric field of the electromagnetic wave is easily held under the conductor ring 14, and the plasma density below the conductor ring 14 increases. Conversely, when the lower surface of the conductor ring 14 is retracted as in the example of FIG. 6, the electric field under the conductor ring 14 is weakened,
The plasma density below the conductor ring 14 decreases.

In order to examine the characteristics of the conductor ring when the arrangement position is changed as in the embodiments of FIGS. 5 and 6, the antenna diameter, the material (dielectric constant) of the conductor ring, and the thickness of the conductor ring are changed. The distribution of the ion current density (ICF) incident on the substrate was examined by simulation. The relative dielectric constant of quartz is 3.
It was set to 5. FIG. 7 shows the result. According to the simulation, the ring with a thick shape protruding downward is
It was found that the effect of increasing the outer circumference of CF was great.

FIG. 8 is a view showing another embodiment of the present invention, in which a conductor ring 14 as an electromagnetic wave distribution corrector is located below the quartz block 12. That is, the upper surface of the conductor ring 14 is located at a position corresponding to the lower surface of the first plate 2a.
By configuring the conductor ring 14 in this manner, there is an effect that the electric field can be efficiently held with a small size.

FIG. 9 is a diagram showing the effect of the outer circumferential gap of the thin conductor ring. Further, the outer circumferential gap refers to a radial gap G between the outer circumference of the conductor ring 14 and the outer circumference of the quartz block 12 in FIG. Small outer clearance, eg 13mm
It can be seen that by setting the degree to less than or equal to the range, the intensity of the electric field immediately below the conductor ring, the resulting power deposit, and the resulting auxiliary plasma density can be changed. if,
When a strong magnetic field condition is commonly used, the outer circumferential gap of the conductor ring may be increased.

FIG. 10 is a cross-sectional view of another embodiment of the present invention, in which the electromagnetic wave distribution compensator 14 is not a continuous ring but a plurality of conductor pieces divided in the circumferential direction and arranged at equal intervals. ing. By using the electromagnetic wave distribution corrector 14 as a plurality of conductor pieces in this manner, there is an effect that the size of the electromagnetic wave distribution corrector can be reduced in size and the processing cost can be reduced.

FIG. 11 is a sectional view of another embodiment of the present invention. A moving mechanism 17 is connected to an electromagnetic wave distribution compensator 14 composed of a conductor ring provided in a cavity 14a of a quartz block 12, and You can move to. With this configuration, the intensity of the electric field held below the electromagnetic wave distribution corrector 14 can be changed, and the distribution of the plasma in the radial direction can be controlled.

FIG. 12 is a cross-sectional view of another embodiment of the present invention. A dielectric 16 is inserted in a space between the chamber 1, the coaxial cable 11, and the first plate 2, and the electromagnetic wave distribution correction is performed. The body 14 includes a correction body main body 14a and an auxiliary plate 14b.
, And the auxiliary plate 14 b protrudes into the dielectric 16. The auxiliary plate 14b is formed of a conductor. The auxiliary plate 14b may be connected to the corrector body 14a or may be separated by a small distance.

The auxiliary plate 14 made of such a lightweight member
The addition of b has the effect of controlling the radial distribution of plasma. That is, since the electromagnetic waves are distributed between the front and back of the auxiliary plate 14b and guided to the correction body 14a, the ratio of the intensity of the electric field formed below the first plate to the intensity of the electric field held under the electromagnetic wave distribution correction body 14 is reduced. This has the effect of controlling the radial distribution of the plasma.

The correction body 14a and the auxiliary plate 14b of the electromagnetic wave distribution corrector 14 may be formed of a thin conductive film. The compensator body 14a and the auxiliary plate 14b may be formed by depositing a conductor film such as aluminum on a dielectric plate such as alumina. With such a configuration, there is an effect that a lightweight and low-cost device can be obtained.

FIG. 13 is a sectional view of another embodiment of the present invention, in which the chamber 1, the first plate 2, and the quartz block 12 are shown.
In the space of the dielectric 16 on the first plate 2 sandwiched by the gaps, the gap in the axial direction is changed in the radial direction by the gap changing plate 1a. In particular, the axial gap above the electromagnetic wave distribution corrector 14 is smaller than the other. With this configuration,
Since the electric field of the electromagnetic wave formed between the electromagnetic wave distribution corrector 14 and the gap changing plate 1a becomes stronger, the electric field held under the electromagnetic wave distribution corrector 14 is lower than the electric field held below the first plate. The intensity ratio can be increased, and there is an effect of increasing the density of plasma generated below the electromagnetic wave distribution corrector 14.

FIG. 14 is a cross-sectional view of another embodiment of the present invention, in which a quartz block 12 having a shower head formed on a surface of a first plate 2 facing a second plate 3 is provided. . An electromagnetic wave distribution corrector 14 is provided on the outer periphery of the quartz block 12.
Is inserted. Such a device configuration is applied to a device that does not want to expose electrodes directly on the surface facing the substrate. With such a configuration, there is an effect that the consumption of the electrodes is suppressed and the life of the device is prolonged.

FIG. 15 is a sectional view of another embodiment of the present invention. The electromagnetic wave distribution corrector 14 includes a plate 14a facing the center of the device and a plate 14b connected to the plate 14a. With this configuration, the auxiliary power deposition 15 generated on the side of the surface 14a opposed to the center of the device.
b is a power deposition 15a formed at the center of the device
Generated near The plate 14b is formed of a conductor, and adjusts the distance between the chamber 1 and the first plate 2,
It has a function to guide a strong electric field to the surface a. With this configuration, a uniform and high-density plasma can be formed in the radial direction within a small radius, and there is an energy saving effect.

FIGS. 16A and 16B are sectional views of another embodiment of the present invention. The electromagnetic wave distribution corrector 14 includes a first correction plate 14a facing the center of the device and a second correction plate 14a connected to the first correction plate 14a.
The correction plate 14b has a substantially L-shaped cross section. That is, the electromagnetic wave distribution corrector includes a first correction plate 14a forming an angle θ1 within 90 ° ± 45 ° with the first plate, and a second correction plate intersecting the first correction plate at an angle θ2 within 90 ° ± 45 °. It consists of When θ1 and θ2 are 90 degrees, it is easy to manufacture the electromagnetic wave distribution corrector 14 and the quartz block 12 surrounding the same, but the auxiliary power digit 15b is generated obliquely with respect to the first plate 2 to increase the diameter. Is designed to be 90 degrees or more.

When the electromagnetic wave distribution compensator 14 is formed in a substantially L-shape in this manner, the first compensator 14 facing the center of the apparatus
An auxiliary power deposition 15b generated on the side of a is generated near the power deposition 15a formed in the center of the device. The second correction plate 14b is formed of a conductor, and has a function of adjusting the distance between the chamber 1 and the first plate 2 to guide a strong electric field to the surface of the first correction plate 14a. With this configuration, a uniform and high-density plasma can be formed in the radial direction within a small radius,
At the same time as the effect of energy saving, the structure is simpler than that of the embodiment of FIG. 15, the assembly with the quartz block 12 is easy, and the manufacturing cost is reduced.

FIG. 17 shows the structure of the electromagnetic wave distribution compensator 14 generated from the study of the workability of the conductor ring for generating the vertical auxiliary plasma and the simulation results thereof. The UHF electric field distribution shows contour lines and electric field vectors together. When the wing extends to the back of the antenna, the structure is complicated. Therefore, a hisher type conductor ring with horizontal wings shown in FIG. 17A has been devised. Further, while studying a simple structure, it has been found that the substantially L-shaped conductor ring of FIG. 17B has equivalent performance.

FIG. 18 is a sectional view of another embodiment of the present invention. This is one in which the substantially L-shaped electromagnetic wave distribution corrector shown in FIG. 16 is applied to an electrode structure as shown in FIG. A quartz block 12 having a shower head is provided on a surface of the first plate 2 facing the second plate 3. The quartz block 12 comprises a quartz block 12a and a quartz block 12b protruding into the plasma from the quartz block 12a. The substantially L-shaped electromagnetic wave distribution corrector 14 is inserted into the quartz block 12b. The quartz block 12a and the quartz block 12b may be separate bodies or may be integrated. The method of dividing the quartz block 12 is determined based on the ease of assembling parts. Such a device configuration is applied to a device that does not want to expose electrodes directly on the surface facing the substrate. With such a configuration, there is an effect that the consumption of the electrodes is suppressed and the life of the device is prolonged.

FIG. 19 is a sectional view of another embodiment of the present invention. An outer peripheral ring 18 is provided on the wall surface of the chamber 1 further outside the electromagnetic wave distribution corrector 14 with a gap between the electromagnetic wave distribution corrector 14. This configuration has the effect of reducing the amount of electromagnetic waves leaking out of the electromagnetic wave distribution corrector 14 along the wall surface of the chamber 1 to the exhaust port 9 and increasing the strength of the power deposition 15.

FIG. 20 is a sectional view of another embodiment of the present invention. The electromagnetic wave distribution corrector 14 includes a plate 14a facing the center of the apparatus and a plurality of plates 14b connected thereto.
14c. The plurality of plates 14b and 14c are arranged with a gap in the axial direction. When the electromagnetic wave distribution compensator 14 is configured in this manner, the auxiliary power deposition 15 generated on the side of the surface 14a facing the center of the device.
The intensity of b can be increased, high density plasma can be formed, and there is an effect of energy saving.

When the plasma processing apparatus to which the present invention is applied is used for a method of manufacturing an LSI by processing a semiconductor substrate, a highly reliable product can be obtained because damage due to non-uniform plasma does not occur. effective.

Although the above is an embodiment for a UHF electromagnetic wave ECR plasma apparatus, the present invention is also applicable to a wave excitation plasma apparatus such as a UHF plasma apparatus having no magnetic field and a microwave plasma apparatus of 2.45 GHz. Can be implemented. For example, FIGS. 21 to 24 show an embodiment in which the present invention is applied to a UHF plasma apparatus having no magnetic field.

First, in the embodiment shown in FIGS.
The first plate 2 constitutes a spoke antenna having the spokes 2c. With this configuration, there is an effect that an inexpensive plasma device with a small number of components can be manufactured without requiring a magnetic field generating coil.

In the embodiment shown in FIGS.
The first plate 2 has a plurality of openings and forms an antenna that extends to the wall surface of the chamber 1. With this configuration, there is an effect that the uniform diameter of the plasma can be increased as compared with the embodiment of FIG.

FIG. 25 shows an embodiment in which the present invention is applied to a surface wave plasma device. The electromagnetic waves enter the space 16 ′ as surface waves, and the electromagnetic waves enter the processing chamber 6 from the slots 19 and 20 via the quartz block 12 to generate plasma. With this configuration, uniform and stable plasma can be generated, and there is an effect that deterioration in uniformity of the processing speed in the substrate surface can be prevented. Further, the present invention can be applied to a plasma CVD apparatus and a sputtering apparatus. Further, the present invention can be applied to a parallel plate capacitively coupled plasma device and an inductively coupled plasma device. 1
When a power supply having a frequency of 00 MHZ or less is used, electric charges are induced on the surface of the electrically floating electromagnetic wave distribution compensator facing the plasma, and an electric field is generated.
Generate an auxiliary plasma.

[0053]

According to the present invention, it is possible to provide a plasma processing apparatus and a plasma processing method capable of performing uniform processing within a substrate surface when performing plasma processing on a substrate having a large diameter.

[Brief description of the drawings]

FIG. 1 is a sectional view of a plasma processing apparatus according to one embodiment of the present invention.

FIG. 2 is a sectional view of the plasma processing apparatus taken along line AA of FIG. 1;

FIG. 3 is a conceptual diagram illustrating the operation and effect of the plasma processing apparatus of FIG.

FIG. 4 shows a UHF electric field intensity E _ab , a power deposition, and an electron obtained by performing a simulation on a conventional plasma processing apparatus and a plasma processing apparatus having a conductor ring according to an embodiment of the present invention. It is a figure which shows the contour line of a density distribution.

FIG. 5 is an explanatory diagram of another embodiment of the present invention.

FIG. 6 is an explanatory diagram of another embodiment of the present invention.

7 is a graph showing the distribution of ICF by changing the antenna diameter, the material (dielectric constant) of the conductor ring, and the thickness of the conductor ring in order to examine the characteristics of the conductor ring in the apparatus of the embodiment shown in FIGS. FIG.

FIG. 8 is an explanatory diagram of another embodiment of the present invention.

FIG. 9 is an explanatory view of another embodiment of the present invention.

FIG. 10 is an explanatory diagram of another embodiment of the present invention.

FIG. 11 is an explanatory diagram of another embodiment of the present invention.

FIG. 12 is an explanatory diagram of another embodiment of the present invention.

FIG. 13 is an explanatory diagram of another embodiment of the present invention.

FIG. 14 is an explanatory diagram of another embodiment of the present invention.

FIG. 15 is an explanatory diagram of another embodiment of the present invention.

FIG. 16 is an explanatory diagram of another embodiment of the present invention.

FIG. 17 is a diagram showing a structure of the electromagnetic wave distribution corrector 14 and a simulation result thereof.

FIG. 18 is an explanatory diagram of another embodiment of the present invention.

FIG. 19 is an explanatory diagram of another embodiment of the present invention.

FIG. 20 is an explanatory diagram of another embodiment of the present invention.

FIG. 21 is an explanatory diagram of another embodiment of the present invention.

FIG. 22 is a BB cross section of FIG.

FIG. 23 is an explanatory diagram of another embodiment of the present invention.

FIG. 24 is a BB cross section of FIG.

FIG. 25 is an explanatory diagram of another embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Chamber, 2 ... 1st board, 2a ... Gas hole, 2c ... Spoke, 3 ... 2nd board, 4 ... Substrate, 5a, 5b ... Power supply, 6 ... Processing chamber, 7 ... Plasma, 8 ... Gas supply means, 9 ... exhaust port,
11: Antenna, 12: Quartz block, 13: Electromagnetic coil, 14, 14a, 14b, 14c: Electromagnetic wave distribution corrector,
15a, b: power deposition, 16: dielectric, 1
6 ': space, 17: moving mechanism, 18: outer ring, 1
9, 20, ... slot

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) H01L 21/205 H01L 21/205 H05H 1/46 H05H 1/46 C B (72) Inventor Ichiro Sasaki Tsuchiura, Ibaraki Pref. 502 Nachi-machi Machinery Research Laboratory Co., Ltd. (72) Inventor Tatsuto Usui 502 Kunitachicho, Tsuchiura-shi, Ibaraki Pref. Machinery Research Laboratory Co., Ltd. (72) Inventor Hironobu Kawahara Kazamatsu City, Yamaguchi Prefecture 794 Address Inside the Kasado Plant of Hitachi, Ltd.

Claims (20)

[Claims] An electromagnetic wave is supplied to a first plate, a plasma is generated in a vacuum atmosphere between the first plate and a second plate disposed opposite to the first plate, and the substrate is placed on the second plate. In a plasma processing apparatus for processing, a dielectric window for transmitting an electromagnetic wave is provided on an outer peripheral portion of the first plate, and an electromagnetic wave distribution made of an electric conductor or a dielectric is provided in the window apart from the first plate. A plasma processing apparatus, wherein a correcting member is embedded such that at least a side surface and a lower surface of the electromagnetic wave distribution correcting member are not exposed to the vacuum atmosphere. 2. A vacuum chamber for holding a vacuum, a mechanism for introducing a gas at a predetermined flow rate into the chamber to maintain a predetermined pressure, and a mechanism for introducing an electromagnetic wave for converting the introduced gas into plasma. A plasma processing apparatus comprising: a window through which the electromagnetic wave is introduced into the vacuum chamber; and a magnetic field generation mechanism that generates a magnetic field within the vacuum chamber. A window is provided, and an electromagnetic wave distribution corrector made of an electric conductor or a dielectric is separated from the first plate in the window so that at least a side surface and a lower surface of the electromagnetic wave distribution corrector are not exposed to the vacuum chamber. A plasma processing apparatus characterized by being buried. 3. The plasma processing apparatus according to claim 1, wherein said electromagnetic wave distribution corrector has a ring shape having substantially the same central axis as said substrate. 4. The plasma processing apparatus according to claim 1, wherein said electromagnetic wave distribution corrector has a fragment shape divided in a circumferential direction. 5. The plasma processing apparatus according to claim 1, wherein a material of the electromagnetic wave distribution corrector is an electric conductor such as aluminum, copper, or iron. 6. The plasma processing apparatus according to claim 1, wherein said electromagnetic wave distribution corrector is a liquid. 7. The plasma processing apparatus according to claim 2, wherein said electromagnetic wave distribution corrector is electrically floating from a conductor surface of said chamber or a dielectric window mechanism for transmitting said electromagnetic wave. apparatus. 8. The plasma processing apparatus according to claim 1, wherein the electromagnetic wave distribution corrector and the chamber are connected via a switch so that a potential of the electromagnetic wave distribution corrector can be controlled. Characteristic plasma processing apparatus. 9. The plasma processing apparatus according to claim 1, wherein said electromagnetic wave distribution corrector is movable up and down. 10. The plasma processing apparatus according to claim 1, wherein a gap changing plate is disposed in a space between the chamber and the upper surfaces of the first plate and the window, and a gap in an axial direction of the space is formed in a radial direction. Wherein the axial gap above the electromagnetic wave distribution corrector is made narrower than the other. 11. The plasma processing apparatus according to claim 1, wherein said electromagnetic wave distribution compensator is provided at a distance of 9 mm from said first plate.
A first distribution correction plate having an angle of 0 ° ± 45 ° or less and a second distribution correction plate intersecting the first distribution correction plate at an angle of 90 ° ± 45 ° or less. Plasma processing equipment. 12. The plasma processing apparatus according to claim 1, wherein said electromagnetic wave distribution compensator is located at a distance from said first plate.
A first distribution correction plate having an angle of 0 ° ± 45 ° or less, and a plurality of second distribution correction plates intersecting the first distribution correction plate at an angle of 90 ° ± 45 ° or less. Characteristic plasma processing apparatus. 13. The plasma processing apparatus according to claim 1, wherein said electromagnetic wave distribution compensator is provided with a distance of 9 m from said first plate.
It comprises a first distribution correction plate having an angle of 0 ° ± 45 ° or less, and a plurality of second distribution correction plates intersecting the first distribution correction plate at an angle of 90 ° ± 45 ° or less. Second
On the wall surface of the chamber corresponding to the outer peripheral side of the distribution correction plate,
A plasma processing apparatus comprising a ring. 14. A plasma processing apparatus according to claim 11, wherein a first distribution correction plate of said electromagnetic wave distribution correction member is substantially perpendicular to said first plate. apparatus. 15. The plasma processing apparatus according to claim 11, wherein an intersection of the first distribution correction plate of the electromagnetic wave distribution correction body with the second distribution correction plate is a first one.
A plasma processing apparatus characterized in that the end is farther from the plate. 16. The plasma processing apparatus according to claim 11, wherein an end opposite to an intersection of the second distribution correction plate surface and the first distribution correction plate surface constituting the electromagnetic wave distribution correction member is formed by a first A plasma processing apparatus extending to the vicinity of the chamber wall behind one plate. 17. A plasma processing method using the plasma processing apparatus according to claim 1, wherein an electromagnetic wave of 100 to 900 MHz is supplied to said first plate 2 and said second plate is
A high frequency power of 100 kHz to 14 MHz is applied to a sample to be processed on a plate by 0.5 W / cm per unit area of the sample to be processed.
A plasma processing method, comprising applying a surface treatment of the sample to be processed by applying ² to 8 W / cm ² . 18. A substrate provided on a second plate by supplying an electromagnetic wave to a first plate to generate plasma in a vacuum atmosphere between the first plate and a second plate disposed opposite to the first plate. In the plasma processing method, the step of setting the atmosphere in which the substrate is mounted on the second plate to a vacuum atmosphere, the step of introducing gas into the vacuum atmosphere, Into the vacuum atmosphere through a dielectric window in which an electric conductor or a dielectric electromagnetic wave distribution compensator made of a dielectric is provided apart from the first plate.
Generating a plasma by introducing an electromagnetic wave of 0 to 900 MHz, etching the substrate placed on the second plate using the plasma, and removing the substrate from the vacuum atmosphere. A plasma processing method characterized by the above-mentioned. 19. A vacuum chamber for holding a vacuum, a mechanism for introducing an electromagnetic wave for converting a gas introduced into the vacuum chamber into a plasma, a dielectric window for introducing the electromagnetic wave into the vacuum chamber, In a plasma processing method for a substrate by a plasma processing apparatus including a magnetic field generating mechanism that generates a magnetic field in the vacuum chamber, a step of evacuating the vacuum chamber in which the substrate is mounted on the second plate; Introducing a gas into the vacuum chamber, through the window provided with an electromagnetic conductor distribution correction body made of an electric conductor or a dielectric provided inside the outer periphery of the first plate and separated from the first plate inside. 100-
Introducing a 900 MHz electromagnetic wave to generate plasma; using the plasma to etch the substrate placed on the second plate; and removing the substrate from the vacuum chamber. A plasma processing method characterized by the above-mentioned. 20. The plasma processing method according to claim 17, wherein said substrate has a diameter of φ200 mm to 350 mm.