JP2007173033A - Plasma treatment device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a plasma treatment device with improved uniformity of plasma treatment with the use of an RF incident window of a stepped structure free from risk of damage due to thermal stress. <P>SOLUTION: In the plasma treatment device in which electromagnetic waves from a plurality of coiled high-frequency antennas are made incident into a vacuum chamber 1 through a disc-like RF incident window 3 of an insulating property and gas in the vacuum chamber 1 is plasmolyzed, the RF incident window 3 is to be formed at nearly uniform thickness with its center part protruded inward in a circular shape, around which (a stepped part 3b) ring-shaped plasma 15 is to be formed. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a plasma processing apparatus, and is suitable, for example, for a plasma processing apparatus having a window for entering an electromagnetic wave in a container.

  In an inductively coupled plasma processing apparatus, in order to turn the gas supplied into the apparatus's container into plasma, an electromagnetic wave is transmitted from an antenna outside the container to the inside of the container through an RF (Radio Frequency) incident window. Is incident. In such a plasma processing apparatus having an RF incident window, a ceramic material is used for the RF incident window in consideration of heat resistance and plasma resistance.

P. L. G. Ventzek, M. Grapperhaus and M. J. Kushner, "Investigation of Electron Source and Ion Flux Uniformity in High Plasma Density Inductively Plasma Tools Using 2-dimensional Modeling", J. Vac. Science Tech. B 12, 3118 (1994).

  In a plasma processing apparatus for semiconductors whose substrate diameter is increasing, the uniformity of film thickness and film quality is more important than ever. For example, in the case of a CVD plasma processing apparatus that embeds an interlayer insulating film or STI (element isolation film), it is necessary to achieve both the uniformity of deposition and sputter etching and the uniformity of the ratio for uniform film formation. . Specifically, in order to improve deposition uniformity, it is necessary to set the distance from the position of the gas nozzle to the substrate within a predetermined range. When ring-shaped plasma is used as a plasma source, it is necessary to set the diameter of the ring-shaped plasma and the distance from the plasma to the substrate within a predetermined range in order to improve the uniformity of sputter etching. That is, to adjust the uniformity of sputter etching, it is necessary to adjust the diameter of the ring-shaped plasma and the height of the substrate.

  Further, it has been reported that the uniformity of sputter etching is improved by forming a step on the plasma side of the RF incident window (Non-Patent Document 1). However, since it is difficult to make the entire surface of the RF incident window made of a ceramic material homogeneous, the physical properties are likely to be different between the central portion and the peripheral portion. In particular, as in Non-Patent Document 1, the central portion is thick, When the step shape is such that the peripheral portion is thin, there is a problem in manufacturing that the difference is further increased. In addition, the RF incident window in the plasma processing apparatus has a temperature distribution in which the temperature is high in the central portion and low in the peripheral portion during the plasma processing. Therefore, when considering the thermal stress of such temperature distribution, However, the stepped shape with a thick and thin peripheral part could not withstand the structure and was highly likely to be damaged by thermal stress. Therefore, an RF incident window having a step structure that can be used practically has been demanded.

  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 that improves the uniformity of plasma processing by using an RF incident window having a step structure that is not damaged by thermal stress. .

A plasma processing apparatus according to a first invention for solving the above-mentioned problems is
In a plasma processing apparatus for making electromagnetic waves from one or a plurality of coiled antennas enter a container through an insulating disk-like window and converting the gas in the container into plasma,
The window is formed with a substantially uniform thickness, and a central portion of the window is projected in a circular shape inside the container so that a ring-shaped plasma is formed around the projected portion. It is characterized by that.

A plasma processing apparatus according to a second invention for solving the above-mentioned problems is as follows.
In the plasma processing apparatus according to the first invention,
The protruding portion is characterized by being protruded through a gentle inclined portion.

A plasma processing apparatus according to a third invention for solving the above-described problem is
In a plasma processing apparatus for making electromagnetic waves from one or a plurality of coiled antennas enter a container through an insulating disk-like window and converting the gas in the container into plasma,
The window is formed by overlapping a disk-shaped first flat plate with a large diameter and a uniform thickness and a disk-shaped second flat plate with a small diameter and a uniform thickness, and the second flat plate side Is arranged inside the container to form a protruding portion, and ring-shaped plasma is formed around the protruding portion.

A plasma processing apparatus according to a fourth invention for solving the above-mentioned problems is as follows.
In the plasma processing apparatus according to the third invention,
The second flat plate is supported on the first flat plate side by a bolt member penetrating the first flat plate.

A plasma processing apparatus according to a fifth invention for solving the above-described problems is
In the plasma processing apparatus according to the third invention,
The second flat plate is supported on the first flat plate side by a support member disposed inside the container.

A plasma processing apparatus according to a sixth invention for solving the above-described problems is
In a plasma processing apparatus for making electromagnetic waves from one or a plurality of coiled antennas enter a container through an insulating disk-like window and converting the gas in the container into plasma,
The window has a ring-shaped ring member with a uniform thickness having a circular opening at the center and a circular dome-shaped dome member with a substantially uniform thickness, and the dome member is located at the opening. It is inserted, and the bottom of the dome member is protruded inside the container so that ring-shaped plasma is formed around the protruding portion.

A plasma processing apparatus according to a seventh invention for solving the above-described problems is
In the plasma processing apparatus according to any one of the first to sixth inventions,
The outer diameter of the protruding portion is made larger than the diameter of the substrate, and the diameter of the one antenna or the average diameter of the plurality of antennas is made larger than the outer diameter of the protruding portion,
When the density center position of the ring-shaped plasma is higher than the inner surface of the container of the projecting portion with respect to the substrate, and the substrate is desired from the density center position of the plasma, the projecting The antenna and the substrate are arranged so that a portion becomes a shadow of the substrate.

A plasma processing apparatus according to an eighth invention for solving the above-mentioned problems is as follows.
In the plasma processing apparatus according to the seventh aspect,
The supply port for supplying a gas into the container with respect to the substrate is made lower than the inner surface of the container at the projecting portion.

  According to the present invention, the window for receiving electromagnetic waves is composed of one or a plurality of insulating members having a substantially uniform thickness. Is easy to form and assemble.

  Further, since the size of the window, the antenna, and the arrangement of the substrate are appropriately set, it is possible to achieve sputter etching uniformity in plasma processing such as CVD and etching.

  Hereinafter, some embodiments of the plasma processing apparatus according to the present invention will be described in detail with reference to FIGS.

Fig.1 (a) is a schematic block diagram which shows an example of embodiment of the plasma processing apparatus based on this invention.
In the plasma processing apparatus according to the present invention, as shown in FIG. 1A, the inside of a cylindrical vacuum chamber 1 is configured as a processing chamber 2, and a step shape is formed in the upper opening of the vacuum chamber 1. An RF incident window 3 made of ceramic and having a circular shape when viewed from above is disposed so as to close the opening. A support table 4 is provided at the lower part of the vacuum chamber 1, and a substrate 5 such as a semiconductor is held on the upper surface of the support table 4.

  A plurality of, for example, circular coil-shaped high-frequency antennas 7 are arranged on the upper part of the RF incident window 3, and the high-frequency antennas 7 are independently connected to the matching unit 8. A power source 9 is connected to supply different currents to the high-frequency antennas 7. In the vacuum chamber 1, a plurality of gas nozzles 10 a and 10 b (supply ports) for introducing a desired gas into the processing chamber 2 are provided evenly in the circumferential direction through the outer wall of the vacuum chamber 1. .

  The position of the support table 4 that supports the substrate 5 can be moved up and down by the lifting device 11. In addition, an electrode portion 12 is provided on the support base 4 that supports the substrate 5, and a low frequency (LF) power source 14 is connected to the electrode portion 12 via a matching unit 13. The low-frequency power source 14 can apply a lower frequency than the high-frequency power source 9 to the electrode unit 12 to apply bias power to the substrate 5.

  In the plasma processing apparatus having the above-described configuration, by supplying power to the high-frequency antenna 7, electromagnetic waves are incident on the processing chamber 2 through the RF incident window 3, and the incident electromagnetic waves are processed through the gas nozzles 10a and 10b. The gas introduced into the gas 2 is ionized to generate plasma 15. At this time, the plasma 15 has a ring shape so as to correlate with the arrangement position of the high frequency antenna 7.

Here, the configuration of the ceramic RF entrance window 3 will be described in detail with reference to FIGS.
As shown in FIGS. 1A and 1B, the RF incident window 3 has a shape in which a central portion of a flat plate having the same thickness is recessed. Specifically, a step portion 3b is projected from the peripheral portion 3a on the lower side (lower side in FIG. 1B) via a vertical portion 3d substantially perpendicular to the peripheral portion 3a. The step surface 3 c, which is the surface on the projecting side of the step portion 3 b, is arranged inside the processing chamber 2 and functions as a step portion of the RF incident window 3. The RF incident window 3 is integrally formed with a substantially uniform thickness, and the bent portion of the vertical portion 3d is formed with an appropriate curvature so that stress is not concentrated. Therefore, since the RF incident window 3 is formed with a substantially uniform thickness and the difference in physical properties between the central portion and the peripheral portion is made as small as possible, a step structure that is not easily damaged by thermal stress can be obtained.

  Furthermore, in the present invention, in order to make sputter etching and deposition on the substrate 5 uniform, the shape of the RF incident window 3 (for example, the outer diameter A of the step portion 3b and the height of the step surface 3c is increased under the following conditions. And other conditions such as the arrangement position of the high-frequency antenna 7 and the substrate 5 are set.

(1) The outer diameter A of the step portion 3b> the diameter C of the substrate 5
(2) Average diameter D of high-frequency antenna 7> Outer diameter A of step portion 3b
(3) Height position E of plasma density center 16 <height B of step surface 3c
(4) When the substrate 5 is desired from the plasma density center 16, the step portion 3b becomes a shadow.
(5) Height G of gas nozzles 10a and 10b> Height B of step surface 3c
Each of the above conditions will be described in detail below with reference to FIGS. 2 (a), 2 (b), 3 (a), and 3 (b), the RF incident window 3, the substrate 5, the high-frequency antenna 7, the plasma 15 and the like from FIG. It is extracted and illustrated.

  In the present invention, the uniformity of the sputter etching amount on the substrate 5 is improved by setting the region of the plasma 15 to the optimum position, and the conditions for this are the above conditions (1) and (2).

(1) The outer diameter A of the step portion 3b> the diameter C of the substrate 5
Here, a simple model that does not consider the shielding effect (the above conditions (3) and (4)) by the step portion 3b is assumed, and the outer diameter A1 of the step portion 3b <the diameter C of the substrate 5 (FIG. 2 ( Description will be made by comparing a)) with the case where the outer diameter A of the step portion 3b> the diameter C of the substrate 5 (FIG. 2B).

  As shown in FIG. 2A, when the outer diameter A1 of the step portion 3b is smaller than the diameter C of the substrate 5, the region of the generated plasma 15 is the outer diameter of the step portion 3b because the step portion 3b exists. The ring shape is larger than A1 and smaller than the diameter C of the substrate 5. In this case, as shown in the graph of FIG. 2 (c), the peak position of the sputter etching amount exists inside the diameter C of the substrate 5, and the sputter etching amount greatly changes in the plane of the substrate 5, and the substrate After increasing from the periphery of 5 toward the center, the profile decreases once.

  On the other hand, as shown in FIG. 2B, when the outer diameter A of the step portion 3b> the diameter C of the substrate 5, the region of the plasma 15 to be generated is the step portion 3b. The ring shape is larger than the outer diameter A and larger than the diameter C of the substrate 5. In this case, as shown in the graph of FIG. 2C, the peak position of the sputter etching amount exists outside the diameter C of the substrate 5, and the sputter etching amount gradually changes in the plane of the substrate 5, The profile gradually decreases from the periphery of the substrate 5 toward the center.

  Considering such a tendency, in order to improve the uniformity of the sputter etching amount on the substrate 5, the region of the plasma 15 to be generated is set so that the outer diameter A of the step portion 3b> the diameter C of the substrate 5 It can be seen that it is desirable to make the diameter larger than C.

(2) Average diameter D of high-frequency antenna 7> Outer diameter A of step portion 3b
As described in the above condition (1), in order to improve the uniformity of the sputter etching amount on the substrate 5, the region of the generated plasma 15 is formed in a ring shape having a diameter larger than the diameter C of the substrate 5. Is desirable. For this purpose, the outer diameter A of the step portion 3b needs to be greater than the diameter C of the substrate 5, and the arrangement position of the high-frequency antenna 7 that generates the plasma 15 is made larger than the outer diameter A of the step portion 3b. It is also important. This is because the generated plasma 15 is mainly influenced by the arrangement position of the high-frequency antenna 7. Therefore, the position of the region where the plasma 15 is generated can be set by the arrangement position of the high-frequency antenna 7, and the arrangement of the high-frequency antenna 7 so that the average diameter D of the high-frequency antenna 7> the outer diameter A of the step portion 3b. The position (horizontal position) may be set. Thereby, the region of the generated plasma 15 can be formed in a ring shape having a diameter larger than the outer diameter A of the step portion 3 b and larger than the diameter C of the substrate 5. The average diameter D is the average of the diameters of the plurality of high frequency antennas 7. When different currents flow through the respective high frequency antennas 7, the average diameter D is set to the diameter of the high frequency antenna 7 according to the amount of current. The weight is weighted and the average of them is obtained. If there is one high-frequency antenna 7, the diameter is used.

  In the present invention, the uniformity of the sputter etching amount on the substrate 5 is improved by utilizing the shielding effect, and the conditions for this are the above conditions (3) and (4).

(3) Height position E of plasma density center 16 <height B of step surface 3c
In order to improve the uniformity of the sputter etching amount on the substrate 5 by using the shielding effect by the step portion 3b of the RF incident window 3, as shown in FIG. , The step portion 3b needs to be shaded so that the entire substrate 5 cannot be seen. For this purpose, at least the height position E of the plasma density center 16 <the height B of the step surface 3c. It will be necessary. Therefore, film formation process conditions such as RF power, pressure, and gas type may be set so that the height position E of the plasma density center 16 <the height B of the step surface 3c. By utilizing this, the uniformity of the sputter etching amount on the substrate 5 can be improved. In addition, since the height E of the plasma density center 16 can be obtained with a relatively high accuracy by plasma analysis, the lower limit value of the height B of the step surface 3c can be obtained in advance.

  Furthermore, in order to further improve the uniformity of the sputter etching amount on the substrate 5, it is necessary to satisfy the above condition (4) in order to optimally use the shielding effect.

(4) When the substrate 5 is desired from the plasma density center 16, the step portion 3b becomes a shadow.
In order to further improve the uniformity of the sputter etching amount on the substrate 5 by optimally using the shielding effect, when the substrate 5 is desired from the plasma density center 16, the step portion 3b may be shaded within an appropriate range. is necessary.

  When the appropriate range is verified, if the substrate 5 is desired from the plasma density center 16, the step portion 3b is not shaded and the entire substrate 5 is visible (radiation range F1 in FIG. 3B). 3), the amount of sputter etching tends to be high at the center of the substrate 5 and low at the periphery of the substrate 5. This is because the radiation range F1 from each point of the plasma density center 16 overlaps more in the central part of the substrate 5 than in the peripheral part of the substrate 5.

  On the other hand, when the substrate 5 is desired from the plasma density center 16, when the step portion 3b is shaded and the center of the substrate 5 is visible (see the radiation range F2 in FIG. 3B), the graph of FIG. As indicated by F2, the amount of sputter etching tends to be low at the center of the substrate 5 and high at the periphery of the substrate 5. This is because the radiation ranges F2 from the respective points of the plasma density center 16 do not overlap at the center of the substrate 5, and the radiation distances from the respective points of the plasma density center 16 are short at the periphery of the substrate 5.

  Considering such a tendency, in order to further improve the uniformity of the sputter etching amount on the substrate 5, the entire substrate 5 cannot be seen within the radiation range F from the plasma density center 16, and from the plasma density center 16. It can be seen that it is desirable to make at least the central portion of the substrate 5 visible in the radiation range F. Therefore, the height position of the substrate 5 and the height position of the plasma density center 16 are such that the entire substrate 5 cannot be seen in the radiation range F from the plasma density center 16 and at least the center portion of the substrate 5 can be seen. Should be set.

  The relationship between the height position of the substrate 5 and the uniformity of the sputter etching amount is as shown in FIG. 4 when the distance from the high-frequency antenna 7 to the substrate 5 is taken on the horizontal axis. It can be seen that the minimum point of the uniformity of the etching amount is at a position away from the high frequency antenna 7 by a predetermined distance. This distance can be determined relatively accurately by plasma analysis if the RF power, pressure, and gas type are determined in advance. Accordingly, the height position of the substrate 5 may be set by obtaining an optimum position from a graph as shown in FIG. When the distance to the substrate can be set (variable), the plasma is set so that the optimum position that minimizes the uniformity is within the variable range of the distance to the substrate even if the conditions of the film formation process change. What is necessary is just to set the upper limit of the height B of the step surface 3c with respect to the height position E of the density center 16.

  In addition, in the present invention, uniformity of deposition on the substrate 5 is ensured, and the condition for this is the condition (5).

(5) Height G of gas nozzle 10b> Height B of step surface 3c
The plurality of gas nozzles 10 a and 10 b are provided in the vacuum chamber 1 evenly in the circumferential direction toward the center of the vacuum chamber 1, and their positions are also important for ensuring uniformity of deposition on the substrate 5. It becomes a condition. Specifically, the position where the step portion 3b of the RF incident window 3 does not interfere with the height position of the gas nozzles 10a and 10b, that is, the position of the gas nozzle 10b so as not to hinder the gas flow from the gas nozzles 10a and 10b. It is necessary that height G> height B of the step surface 3c (see FIG. 1).

  FIG. 5A is a schematic configuration diagram showing another example of the embodiment of the plasma processing apparatus according to the present invention. The plasma processing apparatus of the present embodiment is substantially the same as the plasma processing apparatus shown in FIG. 1 of the first embodiment except for the configuration of the RF incident window 21 as shown in FIG. Therefore, the same reference numerals are given to the apparatus configurations that are the same as those in the plasma processing apparatus shown in FIG. 1, and the present embodiment will be described mainly based on the differences.

  In the present embodiment, the ceramic RF entrance window 21 is provided with a step structure and is not easily damaged by thermal stress, and the manufacturability is further improved.

  As shown in FIGS. 5A and 5B, the RF incident window 21 has a shape in which a central portion of a flat plate having the same thickness is recessed. Specifically, a step portion 21b is provided on the lower side (lower side in FIG. 5B) with respect to the peripheral portion 21a via an inclined portion 21d, and the step portion 21b is provided with a protrusion. The step surface 21c, which is the surface on the side that is formed, is disposed so as to be inside the processing chamber 2, and functions as a step portion of the RF incident window 21. The RF incident window 21 is formed with a substantially uniform thickness. The inclined portion 21d is gently inclined with respect to the peripheral edge portion 21a and the step portion 21b, and stress is applied to the bent portion of the inclined portion 21d. It is formed with a moderate curvature so as not to concentrate. Therefore, since the RF incident window 21 is integrally formed with a substantially uniform thickness and the difference in physical properties between the central portion and the peripheral portion is made as small as possible, a step structure that is not easily damaged by thermal stress can be obtained. In order to improve the manufacturability, it is desirable that the width of the peripheral portion 21a is small. In the case of the RF incident window 21 of the present embodiment, the step portion 21b is connected to the peripheral portion 21a via the inclined portion 21d. The width of the peripheral edge portion 21a is reduced, which contributes to the improvement of manufacturability. In the plasma processing apparatus of the present embodiment, the arrangement position of the high-frequency antenna 7 is arranged along the inclined portion 21d of the RE incident window 21 in accordance with the shape of the RF incident window 21, and this inclined portion 21d. Plasma 15 is generated in the outer peripheral portion of the.

  Further, also in this embodiment, in order to make the sputter etching and deposition on the substrate 5 uniform, the shape of the RF incident window 21 (for example, outside the step portion 21b) under the following conditions as in the first embodiment. The diameter A, the height B of the step surface 21c, etc.), the arrangement positions of the high-frequency antenna 7 and the substrate 5 are set.

(1) Outer diameter A of step portion 21b> Diameter C of substrate 5
(2) Average diameter D of high-frequency antenna 7> Outer diameter A of step portion 21b
(3) The height position E of the plasma density center 16 <the height B of the step surface 21c.
(4) When the substrate 5 is desired from the plasma density center 16, the step portion 21b becomes a shadow.
(5) Height G of gas nozzles 10a and 10b> Height B of step surface 21c
The above conditions are the same as those described in the first embodiment, and thus detailed description thereof is omitted here.

  FIG. 6A is a schematic configuration diagram showing another example of the embodiment of the plasma processing apparatus according to the present invention. The plasma processing apparatus of the present embodiment is also substantially the same as the plasma processing apparatus shown in FIG. 1 of the first embodiment, except for the configuration of the RF incident window 31, as shown in FIG. Therefore, the same reference numerals are given to the apparatus configurations that are the same as those in the plasma processing apparatus shown in FIG. 1, and the present embodiment will be described mainly based on the differences.

  In this embodiment, the ceramic RF entrance window 31 is provided with a step structure and is not easily damaged by thermal stress, and further improves the manufacturability.

  As shown in FIGS. 6A and 6B, the RF incident window 31 has a stepped structure at the center portion by using overlapping disk-shaped flat plates having different diameters. Specifically, with respect to the disk-shaped flat plate ceiling portion 32 having a large diameter and a uniform thickness, a circle having a small diameter and a uniform thickness is provided on the lower side (the lower side in FIG. 6B). A plate-shaped flat step portion 33 is overlapped, and the step portion 33 is suspended and fixed by a suspension bolt 34 penetrating the center portion of the ceiling portion 32. The step surface 33 a, which is the lower surface of the step portion 33, is disposed inside the processing chamber 2 and functions as a step portion of the RF incident window 31. In this way, the disk-shaped flat plates with different thicknesses are overlapped to form the RF incident window 31, and the difference in physical properties between the central portion and the peripheral portion is made as small as possible. Therefore, it is possible to obtain a step structure that is not easily damaged, and the individual members (the ceiling plate 32 and the step portion 33) have a simple shape, so that the manufacturability can also be improved.

  As shown in FIG. 6C (enlarged view of the region H in FIG. 6B), the upper surface of the ceiling portion 32 is sealed to seal between the ceiling portion 32 and the suspension bolt 34. A groove 32a is formed, and a seal member 35 is disposed in the seal groove 32a.

  Further, also in this embodiment, in order to make sputter etching and deposition on the substrate 5 uniform, the shape of the RF incident window 31 (for example, outside of the step portion 33) is obtained under the following conditions as in the first embodiment. The diameter A, the height B of the step surface 33a, etc.), the arrangement positions of the high-frequency antenna 7 and the substrate 5 are set.

(1) The outer diameter A of the step portion 33> the diameter C of the substrate 5
(2) Average diameter D of high-frequency antenna 7> Outer diameter A of step portion 33
(3) Height position E of plasma density center 16 <height B of step surface 33a
(4) When the substrate 5 is desired from the plasma density center 16, the step portion 33 becomes a shadow.
(5) Height G of gas nozzles 10a, 10b> Height B of step surface 33a
Since the above conditions are the same as those described in the first embodiment, detailed description thereof is omitted here.

  FIG. 7A is a schematic configuration diagram showing another example of the embodiment of the plasma processing apparatus according to the present invention. The plasma processing apparatus of the present embodiment is also substantially the same as the plasma processing apparatus shown in FIG. 1 of the first embodiment except for the configuration of the RF incident window 41 as shown in FIG. Therefore, the same reference numerals are given to the apparatus configurations that are the same as those in the plasma processing apparatus shown in FIG. 1, and the present embodiment will be described mainly based on the differences.

  In this embodiment, the ceramic RF entrance window 41 is provided with a step structure and is not easily damaged by thermal stress.

  As shown in FIGS. 7A and 7B, the RF incident window 41 is provided with a step structure in the central portion by inserting and using a dome-shaped member in the central opening portion of the ring-shaped member. It is what I did. Specifically, the ring portion 42 having a uniform thickness having a circular opening at the center, and a dome-shaped dome portion 43 having a substantially uniform thickness and having a flat surface at the bottom, is provided. The dome part 43 is inserted in the opening part of 42, and the bottom part of the dome part 43 is arrange | positioned at the downward side (lower side of FIG.7 (b)). The step surface 43 a, which is the lower surface of the dome 43, is disposed inside the processing chamber 2 and functions as a step portion of the RF incident window 41. Thus, the ring portion 42 having a uniform thickness is combined with the dome portion 43 having a substantially uniform thickness to constitute the RF incident window 41, thereby reducing stress concentration points and reducing the center portion and the peripheral portion. Since the difference in physical properties is made as small as possible, a step structure that is not easily damaged by thermal stress can be obtained.

  In addition, as shown in FIG.7 (c) (enlarged view of the area | region I of FIG.7 (b)), the flange 43a is formed in the edge part of the dome part 43, and the ring part 42 and the flange 43a are connected. In order to seal between the ring portion 42 and the dome portion 43, a seal member 44 is disposed on a seal portion 42 a formed by cutting off the corner of the ring portion 42. Further, in order to protect the sealing member 44 from the plasma 15, a protective groove 42b is formed on the vacuum chamber 1 side of the sealing member 44, and the protective member made of a fluororesin such as Teflon (registered trademark) is formed in the protective groove 42b. 45 is arranged.

  Further, as a structure for sealing between the ring portion 42 and the dome portion 43, a structure as shown in FIG. Specifically, a groove portion 42c is formed on the upper surface of the ring portion 42 between the ring portion 42 and the flange 43a of the dome portion 43, and a seal member 44 is disposed in the groove portion 42c. Further, in order to protect the sealing member 44 from the plasma 15, a protective groove 42d is formed on the vacuum chamber 1 side of the sealing member 44, and a protective member 45 made of fluororesin such as Teflon is disposed in the protective groove 42d. Has been.

  Further, also in this embodiment, in order to make sputter etching and deposition on the substrate 5 uniform, the shape of the RF incident window 41 (for example, outside of the dome 43 is formed under the following conditions as in the first embodiment). The diameter A, the height B of the step surface 43a, etc.), the arrangement positions of the high frequency antenna 7 and the substrate 5, etc. are set.

(1) Outer diameter A of dome portion 43> Diameter C of substrate 5
(2) Average diameter D of high-frequency antenna 7> Outer diameter A of dome portion 43
(3) The height position E of the plasma density center 16 <the height B of the step surface 43a.
(4) When the substrate 5 is desired from the plasma density center 16, the dome portion 43 becomes a shadow.
(5) Height G of gas nozzles 10a and 10b> Height B of step surface 43a
Since the above conditions are the same as those described in the first embodiment, detailed description thereof is omitted here.

  FIG. 8A is a schematic configuration diagram showing another example of the embodiment of the plasma processing apparatus according to the present invention. The plasma processing apparatus of the present embodiment is also substantially the same as the plasma processing apparatus shown in FIG. 1 of the first embodiment, except for the configuration of the RF incident window 51, as shown in FIG. Therefore, the same reference numerals are given to the apparatus configurations that are the same as those in the plasma processing apparatus shown in FIG. 1, and the present embodiment will be described mainly based on the differences.

  In this embodiment, the ceramic RF incident window 51 is provided with a step structure and is not easily damaged by thermal stress, and further improves the manufacturability.

  As shown in FIGS. 8A and 8B, the RF incident window 51 is provided with a step structure at the center portion by using overlapping flat plates having different diameters. Specifically, with respect to the disk-shaped flat plate ceiling 52 having a large diameter and a uniform thickness, a circle having a small diameter and a uniform thickness is provided on the lower side (the lower side in FIG. 8B). A plate-shaped flat step portion 53 is overlapped, and the step portion 53 is supported from below by a rod-shaped support member 54 made of an insulating material extending from the bottom of the vacuum chamber 1. And it arrange | positions so that the step surface 53a which is a lower surface of the step part 53 may become the inner side of the process chamber 2, and functions as a level | step-difference part of the RF incident window 51. FIG. In this way, the disk-shaped flat plates of uniform thickness with different diameters are overlapped to constitute the RF incident window 51, and the difference in physical properties between the central portion and the peripheral portion is made as small as possible. Therefore, it is possible to obtain a step structure that is not easily damaged, and because the individual members (ceiling board 52 and step portion 53) have a simple shape, the manufacturability can also be improved.

  Note that the support member 54 has an elliptical cross-sectional shape, and the long axis side is disposed so as to be directed toward the center of the vacuum chamber 1 so as not to obstruct the gas flow from the gas nozzles 10a and 10b. (See FIG. 8C). The support member 54 may be extended from the wall surface of the vacuum chamber 1 instead of extending from the bottom of the vacuum chamber 1 to support the step portion 53. Further, in the plasma processing apparatus of the present embodiment, the support table 4 can be moved up and down by the elevating device 11, but the support table 4 is supported from the support table 4 when it is fixed without moving up and down. The member 54 may be extended to support the step portion 53.

  Further, in this embodiment, in order to make the sputter etching and deposition on the substrate 5 uniform, the shape of the RF incident window 51 (for example, outside of the step portion 53) is obtained under the following conditions as in the first embodiment. The diameter A, the height B of the step surface 53a, etc.), the arrangement positions of the high-frequency antenna 7 and the substrate 5 are set.

(1) The outer diameter A of the step portion 53> the diameter C of the substrate 5
(2) Average diameter D of high-frequency antenna 7> Outer diameter A of step portion 53
(3) Height position E of plasma density center 16 <height B of step surface 53a
(4) When the substrate 5 is desired from the plasma density center 16, the step portion 53 becomes a shadow.
(5) Height G of gas nozzles 10a and 10b> Height B of step surface 53a
Since the above conditions are the same as those described in the first embodiment, detailed description thereof is omitted here.

  The present invention can be applied to any plasma processing apparatus having a window for entering electromagnetic waves into a container.

It is a block diagram which shows an example of embodiment of the plasma processing apparatus which concerns on this invention. It is a figure explaining the arrangement | positioning conditions of a plasma area | region in the plasma processing apparatus which concerns on this invention. It is a figure explaining the arrangement | positioning conditions using a shielding effect in the plasma processing apparatus which concerns on this invention. It is a figure which shows the relationship between uniformity and a substrate position in the plasma processing apparatus which concerns on this invention. It is a block diagram which shows another example of embodiment of the plasma processing apparatus which concerns on this invention. It is a block diagram which shows another example of embodiment of the plasma processing apparatus which concerns on this invention. It is a block diagram which shows another example of embodiment of the plasma processing apparatus which concerns on this invention. It is a block diagram which shows another example of embodiment of the plasma processing apparatus which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vacuum chamber 2 Deposition room 3 RF entrance window 4 Support stand 5 Substrate 6 Thin film 7 High frequency antenna 8 Matching device 9 High frequency power source 10a Gas nozzle 10b Gas nozzle 11 Lifting device 12 Electrode unit 13 Matching device 14 Low frequency power source 15 Plasma 16 Plasma density center 21 RF incident window 31 RF incident window 41 RF incident window 51 RF incident window

Claims (8)

In a plasma processing apparatus for making electromagnetic waves from one or a plurality of coiled antennas enter a container through an insulating disk-like window and converting the gas in the container into plasma,
The window is integrally formed with a substantially uniform thickness, and a central portion of the window is projected in a circular shape inside the container, and a ring-shaped plasma is formed around the projected portion. A plasma processing apparatus characterized in that it is configured as described above. The plasma processing apparatus according to claim 1,
The plasma processing apparatus is characterized in that the protruding portion is protruded through a gentle inclined portion. In a plasma processing apparatus for making electromagnetic waves from one or a plurality of coiled antennas enter a container through an insulating disk-like window and converting the gas in the container into plasma,
The window is formed by overlapping a disk-shaped first flat plate with a large diameter and a uniform thickness and a disk-shaped second flat plate with a small diameter and a uniform thickness, and the second flat plate side Is disposed on the inside of the container to form a protruding portion, and a ring-shaped plasma is formed around the protruding portion. The plasma processing apparatus according to claim 3, wherein
The plasma processing apparatus, wherein the second flat plate is supported on the first flat plate side by a bolt member penetrating the first flat plate. The plasma processing apparatus according to claim 3, wherein
The plasma processing apparatus, wherein the second flat plate is supported on the first flat plate side by a support member disposed inside the container. In a plasma processing apparatus for making electromagnetic waves from one or a plurality of coiled antennas enter a container through an insulating disk-like window and converting the gas in the container into plasma,
The window has a ring-shaped ring member with a uniform thickness having a circular opening at the center and a circular dome-shaped dome member with a substantially uniform thickness, and the dome member is located at the opening. A plasma processing apparatus, wherein the plasma processing apparatus is inserted so that the bottom of the dome member is protruded inside the container so that a ring-shaped plasma is formed around the protrusion. The plasma processing apparatus according to any one of claims 1 to 6,
The outer diameter of the protruding portion is made larger than the diameter of the substrate, and the diameter of the one antenna or the average diameter of the plurality of antennas is made larger than the outer diameter of the protruding portion,
When the density center position of the ring-shaped plasma is higher than the inner surface of the container of the projecting portion with respect to the substrate, and the substrate is desired from the density center position of the plasma, the projecting The plasma processing apparatus, wherein the antenna and the substrate are arranged so that a portion becomes a shadow of the substrate. The plasma processing apparatus according to claim 8, wherein
A plasma processing apparatus, wherein a supply port for supplying a gas into the container is set lower than an inner surface of the container at the protruding portion with respect to the substrate.

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