JP4499323B2 - Electromagnetic field supply apparatus and plasma processing apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electromagnetic field supply device, and more particularly to an electromagnetic field supply device that supplies an electromagnetic field propagating through a waveguide to an object through a slot.
The present invention also relates to a plasma processing apparatus, and more particularly to a plasma processing apparatus that generates plasma using an electromagnetic field and processes a target object such as a semiconductor or an LCD (liquid crystal desplay).
[0002]
[Prior art]
In the manufacture of semiconductor devices and flat panel displays, plasma processing apparatuses are frequently used to perform processes such as oxide film formation, semiconductor layer crystal growth, etching, and ashing. In one of these plasma processing apparatuses, a microwave is supplied into a processing container from a radial line slot antenna (hereinafter abbreviated as RLSA), and the gas in the processing container is ionized and dissociated by the action of the electromagnetic field. There is a microwave plasma processing apparatus that generates plasma. Since this microwave plasma processing apparatus can generate high-density plasma at a low pressure, efficient plasma processing is possible.
[0003]
FIG. 10 is a diagram illustrating a configuration example of a conventional microwave plasma processing apparatus. FIG. 11 is an enlarged cross-sectional view of a part of the configuration shown in FIG. 10 (connection portion between the cylindrical waveguide and the radial waveguide).
The plasma processing apparatus shown in FIG. 11 accommodates a substrate 4 that is an object to be processed and performs plasma processing on the substrate 4, and supplies microwave MW into the processing container 1 to operate the electromagnetic field. And the electromagnetic field supply device 110 for generating the plasma P in the processing container 1.
[0004]
The processing container 1 has a bottomed cylindrical shape with an open top. A substrate table 3 is fixed to the center of the bottom surface of the processing container 1 via an insulating plate 2. A substrate 4 is disposed on the upper surface of the substrate table 3. An exhaust port 5 for evacuation is provided on the peripheral edge of the bottom surface of the processing container 1. A gas introduction nozzle 6 for introducing gas into the processing container 1 is provided on the side wall of the processing container 1. For example, when this plasma processing apparatus is used as an etching apparatus, a plasma gas such as Ar and an etching gas such as CF ₄ are introduced from the nozzle 6.
[0005]
The upper opening of the processing container 1 is sealed with a dielectric plate 7 so that the plasma P generated in the processing container 1 does not leak outside. An RLSA 112 of an electromagnetic field supply device 110 described later is disposed on the dielectric plate 7. The RLSA 112 is isolated from the processing container 1 by the dielectric plate 7 and is protected from the plasma P generated in the processing container 1. The outer peripheries of the dielectric plate 7 and the RLSA 112 are covered with a shield material 8 arranged in an annular shape on the side wall of the processing container 1 so that the microwave MW does not leak to the outside.
[0006]
The electromagnetic field supply device 110 includes a high-frequency power source 111 that generates a microwave MW and a cylindrical waveguide 113 that connects the RLSA 112.
The RLSA 112 includes two circular conductor plates 122 and 123 arranged opposite to each other to form a radial waveguide 121, and a conductor ring 124 that connects and shields the outer peripheral portions of the two conductor plates 122 and 123. . An opening 125 connected to the cylindrical waveguide 113 is formed in the central portion of the conductor plate 122 on the upper surface of the radial waveguide 121, and the microwave MW is introduced into the radial waveguide 121 from the opening 125. A plurality of slots 126 for supplying the microwave MW propagating in the radial waveguide 121 into the processing container 1 are formed in the conductor plate 123 which is the lower surface of the radial waveguide 121.
[0007]
Bumps 127 made of aluminum are provided at the center on the conductor plate 123. The bump 127 is a member formed in a substantially conical shape protruding toward the opening 125 of the conductor plate 122. By this bump 127, the change in impedance from the cylindrical waveguide 113 to the radial waveguide 121 can be moderated, and the reflection of the microwave MW at the connecting portion between the cylindrical waveguide 113 and the radial waveguide 121 can be reduced. it can. Under the condition that the diameter Lg of the cylindrical waveguide 113 is 90 mm, the height D of the radial waveguide 121 is 15 mm, and the operating frequency is f = 2.45 GHz, the reflectivity (= reflected power / input power) is about −15 dB. For example, the diameter Lb of the bottom surface of the bump 127 is set to 70 mm and the height Hb is set to 50 mm.
A plurality of support columns 128 made of ceramic are provided around the opening 125 of the conductor plate 122. The column 128 is fastened to both the conductor plates 122 and 123 with screws, and prevents the conductor plate 123 from being bent by a load due to the bump 127 and the conductor plate 123 itself.
[0008]
[Problems to be solved by the invention]
However, the conventional bump 127 has a large mass, and the load applied to the conductor plate 123 which is the lower surface of the radial waveguide 121 is large. For this reason, for example, when an impact is given by colliding with the RLSA 112 at the time of assembling, there is a problem that the column 128 supporting the conductor plate 123 is frequently damaged.
In order to suppress the breakage of the column 128, the column 128 may be thickened to increase the strength. However, even if the support 128 is made of ceramic, if the support 128 is made too thick, the influence on the electromagnetic field in the radial waveguide 121 cannot be ignored.
[0009]
The present invention has been made to solve such a problem, and an object thereof is to suppress the breakage of the support column without greatly affecting the electromagnetic field in the waveguide.
[0010]
[Means for Solving the Problems]
In order to achieve such an object, an electromagnetic field supply device according to the present invention is a waveguide comprising a first conductor plate having a plurality of slots and a second conductor plate disposed opposite to the first conductor plate. A cylindrical waveguide connected to the opening of the second conductor plate, and a tapered portion provided at a connection portion between the cylindrical waveguide and the waveguide, and extending from the cylindrical waveguide toward the waveguide. And a support post disposed around the opening of the second conductor plate and fastened to the first and second conductor plates and formed of a dielectric . The tapered portion can moderate the impedance change from the cylindrical waveguide to the waveguide, and reduce the reflection of power at the connecting portion. Therefore, it is not always necessary to provide a bump protruding from the first conductor plate toward the opening of the second conductor plate. Even if the bump is provided, the volume can be reduced and the mass can be reduced as compared with the conventional case. For this reason, the load concerning a 1st conductor board can be made small.
In addition, when providing a bump, you may form the bump with a metal.
[0011]
The electromagnetic field supply device according to the present invention includes a waveguide including a first conductor plate having a plurality of slots and a second conductor plate disposed opposite to the first conductor plate, and a second conductor plate. A cylindrical waveguide connected to the opening, and a bump provided on the first conductor plate and projecting toward the opening of the second conductor plate, wherein the bump is made of a dielectric body, the Ri Do and a metal film covering the surface of the bump body, provided with a strut which is formed in fastened and the dielectric to the first and second conductive plates together is arranged around the opening of the second conductive plate It is characterized by that. By forming the bump body with a dielectric material having a density lower than that of conventionally used aluminum, it is possible to reduce the mass of the entire bump and to reduce the load applied to the first conductor plate. Also, by covering the surface of the bump body with a metal film, the same characteristics as when the entire bump is formed of metal can be obtained. It is not necessary to cover the bump body with the metal film up to the surface facing the first conductor plate.
[0012]
The electromagnetic field supply device according to the present invention includes a waveguide including a first conductor plate having a plurality of slots and a second conductor plate disposed opposite to the first conductor plate, and a second conductor plate. In the electromagnetic field supply device including a cylindrical waveguide connected to the opening and a bump provided on the first conductor plate and projecting toward the opening of the second conductor plate, the bump is made of a hollow metal. The support is formed and disposed around the opening of the second conductor plate and fastened to the first and second conductor plates and formed of a dielectric.
[0013]
In the electromagnetic field supply device described above, a tapered portion that extends from the cylindrical waveguide toward the waveguide may be provided at a connection portion between the cylindrical waveguide and the waveguide. Thereby, the impedance change from a cylindrical waveguide to the said waveguide can be made loose, and reflection of the electric power in a connection part can be reduced. Therefore, the volume of the bump can be reduced as compared with the conventional case, and the mass can be further reduced. For this reason, the load applied to the first conductor plate can be further reduced.
In the electromagnetic field supply device described above, the tip toward the bump opening may be rounded. As a result, it is possible to suppress abnormal discharge caused by the concentration of the electric field at the tip of the bump .
[0014]
In order to achieve the above-described object, a plasma processing apparatus of the present invention includes a processing container in which an object to be processed is accommodated, and an electromagnetic field supply device that supplies an electromagnetic field into the processing container. The above-described electromagnetic field supply device is used as the device.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
(First embodiment)
FIG. 1 is a diagram showing the configuration of the first exemplary embodiment of the present invention. In this figure, the same or corresponding parts as those in FIG. 10 are denoted by the same reference numerals, and description thereof will be omitted as appropriate.
The plasma processing apparatus shown in FIG. 1 accommodates a substrate (object to be processed) 4 such as a semiconductor or LCD and performs a plasma process on the substrate 4, and supplies a microwave MW into the processing container 1. It has an electromagnetic field supply device 10 that generates plasma P in the processing container 1 by the action of the electromagnetic field.
[0016]
The electromagnetic field supply device 10 connects a high-frequency power source 11 that generates a microwave MW having a frequency of 2.45 GHz, a radial line slot antenna (hereinafter abbreviated as RLSA) 12, and the high-frequency power source 11 and the RLSA 12. And a cylindrical waveguide 13. The transmission frequency of the cylindrical waveguide 13 is 2.45 GHz, and the transmission mode is TE ₁₁ .
The cylindrical waveguide 13 is provided with a circular polarization converter 14 on the high frequency power supply 11 side and a matching unit 15 on the RLSA 12 side.
[0017]
The circular polarization converter 14 converts the TE ₁₁ mode microwave MW propagating through the cylindrical waveguide 13 into a circular polarization. Here, the circularly polarized wave is an electromagnetic wave whose electric field vector is a rotating electric field that rotates once in one cycle on a plane perpendicular to the axis of travel.
FIG. 2 is a diagram illustrating a configuration example of the circular polarization converter 14 and illustrates a cross section perpendicular to the axis of the cylindrical waveguide 13. The circularly polarized wave converter 14 shown in this figure has a pair of two columnar protrusions 14A and 14B opposed to each other on the inner wall surface of the cylindrical waveguide 13, or a plurality of these in the axial direction of the cylindrical waveguide 13. It is provided. The two cylindrical protrusions 14A and 14B are arranged in a direction that forms 45 ° with respect to the main direction of the electric field E of the TE ₁₁ mode microwave MW. In addition, you may use the circularly polarized wave converter of another structure.
[0018]
The matching unit 15 performs impedance matching between the supply side (that is, the high frequency power supply 11 side) of the cylindrical waveguide 13 and the load side (that is, the RLSA 12 side). As the matching unit 15, for example, one set includes a plurality of reactance elements provided in the axial direction of the cylindrical waveguide 13, and four sets thereof are provided at an angular interval of 90 ° in the circumferential direction of the cylindrical waveguide 13. Can be used. As the reactance element, a stub made of a conductor or a dielectric projecting radially from the inner wall surface of the cylindrical waveguide 13 or a branch having one end opened in the cylindrical waveguide 13 and the other end electrically short-circuited. A waveguide or the like can be used.
[0019]
FIG. 3 is an enlarged cross-sectional view of the RLSA 12 shown in FIG. The RLSA 12 is composed of two circular conductor plates 22 and 23 arranged opposite to each other to form a radial waveguide 21, and a conductor ring 24 that connects and shields the outer peripheral portions of the two conductor plates 22 and 23. . The conductor plate 22 and the conductor ring 24 that are the upper surface of the radial waveguide 21 are integrally formed, and the conductor plate 23 that is the lower surface of the radial waveguide 21 is fastened to the conductor ring with bolts 30.
A circular opening 25 is formed in the central portion of the conductor plate 22 that becomes the upper surface of the radial waveguide 21, and the flange 13 </ b> F of the cylindrical waveguide 13 is fastened with a bolt (not shown) around the opening 25. . Thereby, the cylindrical waveguide 13 and the radial waveguide 21 are connected, and the microwave MW propagating through the cylindrical waveguide 13 is introduced into the radial waveguide 21 from the opening 25.
[0020]
A plurality of slots 26 for supplying the microwave MW propagating in the radial waveguide 21 into the processing container 1 are formed in the conductor plate 23 which is the lower surface of the radial waveguide 21.
FIG. 4 is a plan view showing an example of the slot arrangement on the conductor plate 23. As shown in this figure, slots 26 extending in the circumferential direction of the conductor plate 23 may be concentrically arranged on the conductor plate 23. The slot 26 may be disposed on the spiral line. The radial spacing of the conductor plate 23 may be about λg (λg is the in-tube wavelength in the radial waveguide 21) or a radiating antenna, or about λg / 3 to λg / 40. Alternatively, a plurality of pairs of slots 26 having a C shape may be arranged to radiate circularly polarized waves.
A dielectric having a relative dielectric constant greater than 1 may be disposed in the radial waveguide 21. As a result, the guide wavelength λg is shortened, so that the slots 26 arranged in the radial direction of the conductor plate 23 can be increased, and the supply efficiency of the microwave MW can be improved.
[0021]
As shown in FIG. 3, the connecting portion between the cylindrical waveguide 13 and the radial waveguide 21 has a tapered portion 29 that spreads from the cylindrical waveguide 13 toward the radial waveguide 21. The cross-sectional shape of the taper may be linear or arcuate.
A bump 27 is provided at the center of the conductor plate 23. The bump 27 is a member formed in a substantially conical shape protruding toward the opening 25 of the conductor plate 22, and is formed of a metal such as aluminum or copper.
[0022]
FIG. 5 is a conceptual diagram showing a desirable side surface shape of the bump 27. As shown in this figure, by rounding the tip of the bump 27 into a spherical shape, it is possible to suppress the occurrence of abnormal discharge due to the concentration of the electric field at the tip of the bump 27. Further, by reducing the inclination of the ridge line of the hem portion of the bump 27 with respect to the conductor plate 23, the impedance change at the boundary between the bump 27 and the conductor plate 23 can be reduced, and the reflection of the microwave MW there can be reduced. it can.
Due to the action of the substantially conical bump 27 and the tapered portion 29 described above, the impedance change from the cylindrical waveguide 13 to the radial waveguide 21 is moderated, and the cylindrical waveguide 13 and the radial waveguide 21 are The reflection of the microwave MW at the connecting portion can be reduced.
[0023]
Further, as shown in FIG. 3, a plurality of support columns 28 are arranged around the opening 25 of the conductor plate 22. The column 28 has a columnar shape as a whole, a screw portion is formed on the upper outer surface, and a screw hole is formed on the lower surface. The column is inserted into a rectangular through hole formed in the periphery of the opening 25 of the conductor plate 22 and the flange 13F of the cylindrical waveguide 13, and the bottom surface of the column 28 is in contact with the conductor plate 23. By inserting the bolt 31 from below into the screw hole of the support 28, the support 28 is fastened to the conductor plate 23. Moreover, the support | pillar 28 is fastened to the conductor board 22 by inserting the nut 32 in the thread part which protrudes upwards from the flange 13F. By fastening the support post 28 to both the conductor plates 22 and 23 in this way, the vicinity of the center of the conductor plate 23 is supported by the support post 28, and the conductor plate 23 is bent by the load of the bump 27 and the conductor plate 23 itself. Can be prevented. In addition, the influence which it has on the electromagnetic field in the radial waveguide 21 is suppressed by forming the support | pillar 28 and the volt | bolt 31 with dielectric materials, such as a ceramic.
[0024]
Next, the operation of the plasma processing apparatus shown in FIGS. 1 to 5 will be described. FIG. 6 is a conceptual diagram showing a state of propagation of the microwave MW at the connection portion between the cylindrical waveguide 13 and the radial waveguide 21.
The microwave MW generated by the high-frequency power source 11 propagates through the cylindrical waveguide 13 in the TE ₁₁ mode, is converted into circularly polarized wave by the circularly polarized wave converter 14, and the cylindrical waveguide 13 and the radial waveguide 21 Reach the connection. At this connection portion, the microwave MW is divided into left and right within a plane including the axis of the cylindrical waveguide 13 by the bumps 27 as shown in FIG. The direction is gradually inclined by the bump 27 and the taper portion 29, and finally changes in the vertical direction. The microwave MW thus introduced into the radial waveguide 21 propagates in the radial direction in the TEM mode.
[0025]
The microwaves MW propagating through the radial waveguide 21 are supplied into the processing container 1 via the dielectric plate 7 from a plurality of slots 26 formed in the conductor plate 23 which is the lower surface of the radial waveguide 21. In the processing chamber 1, the plasma gas introduced from the nozzle 6 is ionized by the electromagnetic field of the microwave MW, and in some cases dissociated to generate plasma P, and the substrate 4 is processed.
[0026]
Since the microwave MW propagates through the cylindrical waveguide 13 in the TE ₁₁ mode, the electric field strength distribution in the radial waveguide 21 has an electric field strength in the direction of the electric field E in the cylindrical waveguide 13 as shown in FIG. The strong part F is strongly unevenly distributed. However, since the microwave MW propagating through the cylindrical waveguide 13 is circularly polarized, and the electric field E of the microwave MW rotates around the axis of the cylindrical waveguide 13, the electric field strength in the radial waveguide 21 is increased. The portion F having a strong rotation also rotates in the same manner. Therefore, the electric field intensity distribution in the radial waveguide 21 is made uniform on a time average basis. As a result, the electric field intensity distribution in the processing container 1 is also made uniform over time, so that uniform processing can be performed in the plane of the substrate 4 using the plasma P generated by the electromagnetic field in the processing container 1. it can.
[0027]
Next, the simulation result about the electromagnetic field supply apparatus 10 shown in FIG. 3 is shown. In this simulation, the diameter Lg of the cylindrical waveguide 13 is φ90 mm, the diameter La and the height D of the radial waveguide 21 are φ480 mm and 15 mm, respectively. Further, the difference Wt between the radius of the bottom surface of the tapered portion 29 and the radius (Lg / 2) of the cylindrical waveguide 13 was 5 mm, and the height Ht of the tapered portion 81 was 5 mm. The bumps 27 are made of aluminum, and the diameter Lb and height Hb of the bottom surface are set to φ85 mm and 30 mm, respectively. In such a configuration, a simulation was performed on the assumption that a microwave MW having a frequency of 2.45 GHz was input to the cylindrical waveguide 13. As a result, the reflectance at the connection portion between the cylindrical waveguide 13 and the radial waveguide 21 ( The reflected power / input power was -15 dB.
[0028]
From this simulation result, the reflectance obtained by using the bump 127 having Lb = φ70 mm and Hb = 50 mm in the related art is provided in the electromagnetic field supply apparatus 10 shown in FIG. It can be seen that the bump 27 having a small Lb = φ85 mm and Hb = 30 mm is obtained. By reducing the volume of the bump 27, the mass thereof can be reduced and the load applied to the conductor plate 23 can be reduced. For this reason, when an impact is applied to the RLSA 12, it is possible to reduce the frequency with which the support 28 supporting the conductor plate 23 is damaged.
In this electromagnetic field supply device 10, since the frequency of breakage of the support 28 can be reduced without increasing the thickness of the support 28, the influence given to the electromagnetic field in the radial waveguide 21 is small.
[0029]
Further, when a similar simulation was performed by changing only the diameter Lb of the bottom surface of the bump 27, the diameter Lb was 90 mm or more and the reflectance was -20 dB or less. From this result, a taper portion 29 with Wt = Ht = 5 mm is formed, and a bump 27 with Lb ≧ φ90 mm and Hb = 30 mm is used, so that reflection at the connecting portion between the cylindrical waveguide 13 and the radial waveguide 21 is performed. It can be said that it can be made extremely small.
[0030]
(Second Embodiment)
FIG. 8 is a cross-sectional view showing the main configuration of the second embodiment of the present invention. In this figure, the same or corresponding parts as those in FIGS. 1 and 3 are denoted by the same reference numerals, and description thereof will be omitted as appropriate.
The electromagnetic field supply apparatus 10 shown in FIGS. 1 and 3 is provided with the bump 27 and the taper portion 29, but the bump 27 is not provided in the electromagnetic field supply apparatus shown in FIG. 8. However, since only the taper portion 29 </ b> A can act to moderate the impedance change from the cylindrical waveguide 13 to the radial waveguide 21, the diameter Lg of the cylindrical waveguide 13 and the height D of the radial waveguide 21 can be obtained. By adjusting the ratio, it is possible to obtain a reflectance comparable to that of the electromagnetic field supply device 10 shown in FIGS.
[0031]
As shown in FIG. 8, by removing the bumps 27 from the conductor plate 23, the load applied to the conductor plate 23 can be further reduced. For this reason, when an impact is applied to the RLSA 12A, it is possible to further reduce the frequency with which the support 28 supporting the conductive plate 23 is damaged.
[0032]
(Third embodiment)
FIG. 9 is a cross-sectional view showing the main configuration of the third embodiment of the present invention. In this figure, the same or corresponding parts as those in FIGS. 1 and 3 are denoted by the same reference numerals, and description thereof will be omitted as appropriate.
The electromagnetic field supply device shown in FIG. 9 has a bump 40 composed of a bump body 41 and a metal thin film 42 covering the surface of the bump body 41.
[0033]
The bump body 41 is formed of a dielectric material having a density lower than that of aluminum conventionally used for bump formation. Specifically, it is made of a plastic having a density smaller than 2.69 × 10 ³ kg / m ³ at 20 ° C. The bump body 41 may also be formed of a porous material having a lower density than aluminum. The size of the bump body 41 may be approximately the same as the size of the metal bump 127 that has been conventionally used.
The metal thin film 42 is made of, for example, aluminum, copper, silver, or the like, and the thickness thereof can be set to about 0.1 mm, for example. The metal thin film 42 does not need to cover the lower surface of the bump 40, that is, the surface facing the conductor plate 23.
[0034]
Thus, by forming the bump body 41 with a material having a low density, the mass of the entire bump 40 can be reduced, and the load applied to the conductor plate 23 can be reduced. For this reason, when an impact is applied to the RLSA 12B, it is possible to reduce the frequency with which the support 28 supporting the conductor plate 23 is damaged.
Further, by covering the surface of the bump body 41 with the metal thin film 42, the same characteristics as when the entire bump is formed of metal can be obtained.
In the electromagnetic field supply device shown in FIG. 9, the frequency of breakage of the support 28 can be reduced without increasing the thickness of the support 28. Therefore, the influence exerted on the electromagnetic field in the radial waveguide 21 is small.
[0035]
In the electromagnetic field supply device shown in FIG. 9, the tapered portion 29 may be provided in the same manner as in FIG. 3, although the tapered portion is not provided at the connecting portion between the cylindrical waveguide 13 and the radial waveguide 21. Thereby, the volume of the bump 40 can be reduced and the mass can be further reduced. Therefore, the load applied to the conductor plate 23 can be further reduced, and the frequency with which the support 28 is broken can be further reduced.
Even if the bump is formed of a hollow metal, it is possible to reduce the mass of the bump, reduce the load applied to the conductor plate 23, and thus reduce the frequency of breakage of the support column 28 supporting the conductor plate 23.
[0036]
Although the example using the microwave MW having a frequency of 2.45 GHz has been described above, the usable frequency is not limited to 2.45 GHz. For example, the same effect can be obtained for microwaves having a frequency of 1 GHz to several tens of GHz. Further, the same effect can be obtained even when a high frequency including a frequency band lower than the microwave is used.
The transmission mode of the cylindrical waveguide 13 may be a TM ₀₁ mode.
[0037]
Moreover, although RLSA12, 12A, 12B was demonstrated as an example of a slot antenna, it is not limited to this, Other slot antennas may be used.
The plasma processing apparatus of the present invention can be used for an etching apparatus, a CVD apparatus, an ashing apparatus, and the like.
[0038]
【The invention's effect】
As described above, the present invention has a tapered portion at the connecting portion between the waveguide made of the first and second conductor plates and the cylindrical waveguide. By this taper portion, the impedance change from the cylindrical waveguide to the waveguide can be moderated, and the reflection of power at the connection portion can be reduced. Therefore, it is not always necessary to provide bumps on the first conductor plate, and even if bumps are provided, the volume can be reduced and the mass can be reduced as compared with the prior art. For this reason, the load concerning a 1st conductor board can be made small. Therefore, it is possible to suppress breakage of the column supporting the first conductor plate without greatly affecting the electromagnetic field in the radial waveguide.
[0039]
Further, the present invention uses a bump comprising a bump body made of a dielectric and a metal film covering the surface of the bump body. By forming the bump body with a dielectric material having a density lower than that of conventionally used aluminum, the mass of the bump can be made smaller than in the conventional case, and the load applied to the first conductor plate can be reduced. Therefore, it is possible to suppress breakage of the column supporting the first conductor plate without greatly affecting the electromagnetic field in the radial waveguide.
[Brief description of the drawings]
FIG. 1 is a diagram showing a configuration of a first exemplary embodiment of the present invention.
FIG. 2 is a diagram illustrating a configuration example of a circularly polarized wave converter.
FIG. 3 is an enlarged cross-sectional view of a radial line slot antenna.
4 is a plan view of a conductor plate serving as a lower surface of the radial waveguide as viewed from the direction of the line IV-IV ′ in FIG. 3;
FIG. 5 is a conceptual diagram showing a desirable side surface shape of a bump.
FIG. 6 is a conceptual diagram showing a state of propagation of microwaves at a connection portion between a cylindrical waveguide and a radial waveguide.
FIG. 7 is a diagram for explaining the distribution of microwaves in a radial waveguide.
FIG. 8 is a cross-sectional view showing a main configuration of a second embodiment of the present invention.
FIG. 9 is a cross-sectional view showing a main configuration of a third embodiment of the present invention.
FIG. 10 is a diagram showing a configuration example of a conventional microwave plasma processing apparatus.
FIG. 11 is an enlarged cross-sectional view of a connection portion between a cylindrical waveguide and a radial waveguide.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Processing container, 2 ... Insulating plate, 3 ... Substrate stand, 4 ... Substrate (object to be processed), 5 ... Exhaust port, 6 ... Nozzle for gas introduction, 7 ... Dielectric plate, 8 ... Shield material, 10 ... Electromagnetic Field supply device 11... High frequency power supply 12, 12 A, 12 B Radial line slot antenna (RLSA) 13 Cylindrical waveguide 14 Circular polarization converter 14 A 14 B Stub 15 Matching unit 21 ... Radial waveguide, 22, 22A, 22B ... Circular conductor plate (second conductor plate), 23 ... Circular conductor plate (first conductor plate), 24 ... Ring member, 25 ... Opening, 26 ... Slot, 27, 40 ... Bump, 28 ... Post, 29,29A ... Tapered portion, 30,31 ... Bolt, 32 ... Nut, 41 ... Bump body, 42 ... Metal thin film, E ... Electric field, F ... Part with high electric field strength, MW ... Micro Wave, P ... Plasma.

Claims (8)

A waveguide comprising a first conductor plate having a plurality of slots and a second conductor plate disposed opposite to the first conductor plate; a cylindrical waveguide connected to an opening of the second conductor plate; In an electromagnetic field supply device comprising:
The connecting portion between the waveguide and the cylindrical waveguide, have a tapered portion extending toward the waveguide from the cylindrical waveguide,
Electromagnetic field supply apparatus according to claim Rukoto includes a strut formed by fastened and dielectric to said first and second conductive plates together is arranged around the opening of the second conductive plate. The electromagnetic field supply device according to claim 1,
An electromagnetic field supply device comprising a bump provided on the first conductor plate and projecting toward an opening of the second conductor plate. The electromagnetic field supply device according to claim 2,
2. The electromagnetic field supply device according to claim 1, wherein the bump is made of metal. A waveguide comprising a first conductor plate having a plurality of slots and a second conductor plate disposed opposite to the first conductor plate; a cylindrical waveguide connected to an opening of the second conductor plate; An electromagnetic field supply device including a bump provided on the first conductor plate and protruding toward an opening of the second conductor plate;
The bumps, Ri Do from the bump main body formed of a dielectric material, a metal film covering the surface of the bump body,
Electromagnetic field supply apparatus according to claim Rukoto includes a strut formed by fastened and dielectric to said first and second conductive plates together is arranged around the opening of the second conductive plate. A waveguide comprising a first conductor plate having a plurality of slots and a second conductor plate disposed opposite to the first conductor plate; a cylindrical waveguide connected to an opening of the second conductor plate; An electromagnetic field supply device including a bump provided on the first conductor plate and protruding toward an opening of the second conductor plate;
The bump is formed of a hollow metal ,
Electromagnetic field supply apparatus according to claim Rukoto includes a strut formed by fastened and dielectric to said first and second conductive plates together is arranged around the opening of the second conductive plate. In the electromagnetic field supply device according to claim 4 or 5 ,
An electromagnetic field supply device having a taper portion extending from the cylindrical waveguide toward the waveguide at a connection portion between the cylindrical waveguide and the waveguide. In the electromagnetic field supply device according to any one of claims 2 to 6 ,
The electromagnetic field supply device according to claim 1, wherein a tip of the bump toward the opening is rounded. In a plasma processing apparatus including a processing container in which an object to be processed is stored, and an electromagnetic field supply device that supplies an electromagnetic field in the processing container,
The said electromagnetic field supply apparatus is an electromagnetic field supply apparatus of any one of Claims 1-7, The plasma processing apparatus characterized by the above-mentioned.

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