JP4481538B2 - 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. 11 is a diagram illustrating a configuration example of a conventional microwave plasma processing apparatus. The plasma processing apparatus shown in this figure accommodates a substrate 4 that is an object to be processed and performs plasma processing on the substrate 4, and supplies the microwave MW into the processing vessel 1 and the action of its electromagnetic field. And the electromagnetic field supply device 110 for generating the plasma P in the processing container 1.
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, plasma gas such as Ar from the nozzle 6 and CF _Four Etching gas such as is introduced.
[0004]
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.
[0005]
The electromagnetic field supply device 110 includes a high-frequency power source 111 that generates a microwave MW, an RLSA 112, and a coaxial waveguide 113 that connects the high-frequency power source 111 and the RLSA 112.
The RLSA 112 includes two circular conductor plates 122 and 123 that form a radial waveguide 121 and parallel to each other, and a conductor ring 124 that connects and shields the outer peripheral portions of the two conductor plates 122 and 123. An opening 125 for introducing the microwave MW from the coaxial waveguide 113 into the radial waveguide 121 is formed at the center of the conductor plate 122 that is the upper surface of the radial waveguide 121. 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.
The coaxial waveguide 113 includes an outer conductor 113A and an inner conductor 113B arranged coaxially. The outer conductor 113A is connected around the opening 125 of the conductor plate 122 of the RLSA 112, and the inner conductor 113B passes through the opening 125. Are connected to the center of the conductor plate 123 of the RLSA 112.
[0006]
In such a configuration, the microwave MW generated by the high frequency power supply 111 is introduced into the radial waveguide 121 via the coaxial waveguide 113. Then, it propagates radially in the radial waveguide 121 and is supplied into the processing container 1 from the slot 126 via the dielectric plate 7. 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.
[0007]
[Problems to be solved by the invention]
However, the coaxial waveguide 113 used in the conventional electromagnetic field supply device 110 has low transmission efficiency because the transmission power is easily converted into heat and the transmission loss is large. For this reason, the conventional plasma processing apparatus using the electromagnetic field supply apparatus 110 has a problem that the generation efficiency of the plasma P is low.
Further, when a large electric power is supplied to the coaxial waveguide 113 and the inner conductor 113B is overheated, the heat of the inner conductor 113B causes the conductor plate 123 of the RLSA 112 to be distorted at the connection portion with the inner conductor 113B, and as a result, the inner conductor 113B and There was a gap between the conductor plate 123 and abnormal discharge sometimes occurred. In order to prevent this, it is necessary to provide a cooling mechanism in the thin inner conductor 113B, but the structure becomes complicated and the cost increases. For this reason, the conventional plasma processing apparatus has a problem that it is difficult to obtain a stable operation at a low cost.
[0008]
The present invention has been made to solve such problems, and an object thereof is to improve the supply efficiency of the electromagnetic field.
Another object is to improve plasma generation efficiency.
Another object is to obtain a stable operation at a low cost.
[0009]
[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. And a cylindrical waveguide connected to the opening of the second conductor plate, and projecting toward the opening of the second conductor plate provided on the first conductor plate and at least partly formed of a dielectric. With bumps The bump has a multilayer structure in which layers made of metal and layers made of a dielectric are alternately arranged. It is characterized by that.
Comparing a cylindrical waveguide and a coaxial waveguide having the same transmission frequency, the cylindrical waveguide generally has a larger characteristic impedance than the coaxial waveguide. Therefore, the wall current generated when the same power is applied is smaller in the cylindrical waveguide than in the coaxial waveguide. As the wall current is smaller, the transmission loss due to the transmission power being converted into heat becomes smaller. Therefore, the transmission loss can be reduced by using a cylindrical waveguide having a smaller wall current.
Also, It is a multilayer structure in which layers made of metal and layers made of dielectric are alternately arranged. By providing the bumps, the impedance change from the cylindrical waveguide to the waveguide constituted by the two conductor plates can be moderated, and the reflection of power at the connecting portion between them can be reduced.
Further, since the cylindrical waveguide does not have an inner conductor, abnormal discharge due to overheating of the inner conductor does not occur. Therefore, it is not necessary to provide a complicated structure such as a cooling mechanism in order to prevent abnormal discharge.
[0010]
In this electromagnetic field supply device , Ba The tip toward the opening of the amplifier 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.
In addition, 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 constituted by two conductor plates. As a result, the impedance change from the cylindrical waveguide to the waveguide can be made more gradual, and the reflection of power at the connecting portion between them can be further reduced.
[0011]
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.
[0012]
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. 11 are denoted by the same reference numerals, and description thereof will be omitted as appropriate.
[0013]
The plasma processing apparatus shown in FIG. 1 accommodates a substrate 4 such as a semiconductor or LCD, which is an object to be processed, and performs plasma processing on the substrate 4, and supplies a microwave MW into the processing vessel 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.
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 It is.
[0014]
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 inner surface position of the conductor ring 24 is substantially the same as the radial position of the inner surface of the side wall of the processing container 1. The length of the difference between the inner surface position of the shield material 8 and the radial position of the inner surface of the side wall of the processing container 1 is a space formed by the lower surface of the conductor plate 23, the upper surface of the side wall of the processing container 1, and the inner surface of the shield material 8. The wavelength λg ′ of the microwave MW in FIG. Other dimensions may be used.
An opening 25 connected to the cylindrical waveguide 14 is formed in the central portion of the conductor plate 22 that becomes the upper surface of the radial waveguide 21, and the microwave MW is introduced into the radial waveguide 21 from the opening 25. 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.
[0015]
FIG. 2 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.
[0016]
As shown in FIG. 1, a bump 27 made of a dielectric material 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. The bump 27 is preferably formed of a dielectric having a relative dielectric constant of 10 or more, but may be smaller than that. By this bump 27, the change in impedance from the cylindrical waveguide 13 to the radial waveguide 21 can be moderated, and the reflection of the microwave MW at the connecting portion between the cylindrical waveguide 13 and the radial waveguide 21 can be reduced. it can. For example, when the substantially conical bump 27 is formed of a dielectric having a relative dielectric constant εr = 20 and the bottom surface has a diameter of 70 mm and a height of 48 mm, the reflectivity (reflected power / incident power) is approximately 20 dB or less. A good simulation result is obtained.
[0017]
FIG. 3 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 substantially 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 can be reduced there. .
As shown in FIG. 1, a plurality of pillars 28 made of a dielectric are provided around the bumps 27. The column 28 is fastened to both the conductor plates 22 and 23 to prevent the conductor plate 23 from being bent by the load of the bumps 27.
[0018]
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.
The circular polarization converter 14 is a TE that propagates through the cylindrical waveguide 13. ₁₁ The mode microwave MW is converted into a circularly polarized wave. 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. 4 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 made of TE. ₁₁ It is arranged in a direction forming 45 ° with respect to the main direction of the electric field E of the mode microwave MW. In addition, you may use the circularly polarized wave converter of another structure.
[0019]
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, a plurality of reactance elements provided in the axial direction of the cylindrical waveguide 13 and four sets in the circumferential direction of the cylindrical waveguide 13 at an angular interval of 90 ° 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.
[0020]
Next, the operation of the plasma processing apparatus shown in FIG. 1 will be described. FIG. 5 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 supply 11 is converted into a circularly polarized wave by the circularly polarized wave converter 14 provided in the cylindrical waveguide 13 and propagates toward the radial waveguide 21. Microwave MW uses cylindrical waveguide 13 through TE. ₁₁ Since the propagation in the mode is, the direction of the electric field E of the microwave MW is the “horizontal direction” perpendicular to the axis of the cylindrical waveguide 13, but the microwave MW is connected to the cylindrical waveguide 13 and the radial waveguide 21. As shown in FIG. 5, the direction of the electric field E of the microwave MW gradually changes to a “vertical direction” perpendicular to the conductor plates 22 and 23 by the bumps 27 as shown in FIG. The microwave MW introduced into the radial waveguide 21 propagates in the radial direction in the TEM mode.
[0021]
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.
[0022]
Next, the effect obtained by the plasma processing apparatus shown in FIG. 1 will be described. The electromagnetic field supply apparatus 10 generally uses a cylindrical waveguide 13 having a large characteristic impedance. According to the JIS standard, the characteristic impedance of the coaxial waveguide 113 for 2.45 GHz is 50Ω, whereas the characteristic impedance of the cylindrical waveguide 13 for the same frequency is as large as 500 to 600Ω. For this reason, the wall surface current generated when the same power is applied is smaller in the cylindrical waveguide 13 than in the coaxial waveguide 113. Since the transmission loss due to the transmission power being converted into heat becomes smaller as the wall current becomes smaller, the transmission loss can be reduced by using the cylindrical waveguide 13 whose wall current is relatively small.
[0023]
Further, by providing the bumps 27 made of a dielectric, the change in impedance from the cylindrical waveguide 13 to the radial waveguide 21 is moderated, and the electric power at the connection portion between the cylindrical waveguide 13 and the radial waveguide 21 is reduced. Reflection can be reduced.
Thus, by reducing the transmission loss and the reflection of electric power, the electromagnetic field supply efficiency by the electromagnetic field supply apparatus 10 can be improved. Furthermore, by forming a plasma processing apparatus using the electromagnetic field supply apparatus 10, the generation efficiency of the plasma P can be improved.
[0024]
Further, since the cylindrical waveguide 13 used in the electromagnetic field supply device 10 does not have the inner conductor 113B like the coaxial waveguide 113, abnormal discharge due to overheating of the inner conductor does not occur. Although the electromagnetic field supply device 10 includes the bumps 27, the amount of heat generated by the cylindrical waveguide 13 is smaller than that of the coaxial waveguide 113. Therefore, even when large power is supplied to the cylindrical waveguide 13, the cylindrical waveguide 13 Abnormal discharge caused by the bump 27 being overheated by heat from the tube 13 is unlikely to occur. Therefore, it is not necessary to provide a complicated structure such as a cooling mechanism in order to prevent abnormal discharge. Therefore, stable operation of the electromagnetic field supply apparatus 10 and the plasma processing apparatus can be realized at low cost.
[0025]
Further, the microwave MW passes the cylindrical waveguide 13 through the TE. ₁₁ Propagation in the mode causes the electric field intensity distribution in the radial waveguide 21 to have a portion F having a high electric field intensity unevenly distributed in the direction of the electric field E in the cylindrical waveguide 13 as shown in FIG. 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.
[0026]
Next, a modified example of the bump 27 will be described. 7 to 9 are diagrams showing modified examples of the bumps.
The bumps 27 shown in FIG. 1 are made of only a dielectric, whereas the bumps 30 shown in FIG. 7A are made of a lower layer 31 made of a metal such as aluminum or copper, and a dielectric. It has a two-layer structure composed of the formed upper layer 32.
In order to join the upper layer 32 to the lower layer 31, for example, as shown in FIG. 7B, the upper layer 32 and the lower layer 31 may be fastened with bolts 33. Further, as shown in FIG. 7C, a metal thin film 34 may be formed on the lower surface of the upper layer 32 formed of a dielectric, and the upper layer 32 and the lower layer 31 may be thermocompression bonded. In this case, a brazing material may be used. By forming the metal thin film 34 with a material having good thermal conductivity, the heat generated in the upper layer 32 is released to the conductor plate 23 through the lower layer 31, and overheating of the bumps 30 can be prevented.
[0027]
Further, like the bump 40 shown in FIG. 8A, the lower layer 41 may be formed of a dielectric, and the upper layer 42 may be formed of metal.
Further, like the bump 50 shown in FIG. 8 (b), it has a multilayer structure in which layers 51 and 53 formed of metal and layers 52 and 54 formed of a dielectric are alternately arranged. Also good.
Further, like the bump 60 shown in FIG. 8C, the bump body 61 may be formed of a dielectric, and a part of the surface of the bump body 61 may be covered with the metal thin film 62. .
Further, like the bump 70 shown in FIG. 9, portions 71, 73, 75, 77 made of metal and portions 72, 74, 76, 78 made of dielectric are formed by the surface including the axis of the bump 70. You may have the structure divided | segmented into.
[0028]
As described above, the bumps are not necessarily formed only from the dielectric, and may be partially formed from metal. By partially forming a metal, a low-cost dielectric having a low relative dielectric constant can be used. Therefore, the manufacturing cost of bumps can be reduced.
[0029]
(Second Embodiment)
FIG. 10 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 7 are denoted by the same reference numerals, and description thereof will be omitted as appropriate.
The electromagnetic field supply device shown in FIG. 10 has a tapered portion 81 that extends from the cylindrical waveguide 13 toward the conductor plate 22A at the connecting portion between the cylindrical waveguide 13 and the radial waveguide 21. A bump 30 is provided at the center of the conductor plate 23. The bump 30 includes a lower layer 31 formed of metal and an upper layer 32 formed of a dielectric.
Like this electromagnetic field supply device, the bumps 30 are provided, and the tapered portion 81 is provided at the connecting portion between the cylindrical waveguide 13 and the radial waveguide 21, so that the cylindrical waveguide 13 is connected to the radial waveguide 21. Impedance changes can be made more gradual, and the reflection of power at the connection between the two can be further reduced.
[0030]
The simulation result about the reflectance of this electromagnetic field supply apparatus 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. The difference Wt between the radius of the bottom surface of the tapered portion 81 and the radius of the cylindrical waveguide 13 (Lg / 2) was 5 mm, and the height Ht of the tapered portion 81 was 5 mm. Further, the diameter Lb and height Hb of the bottom surface of the bump 30 are set to φ70 mm and 50 mm, the lower layer 31 of the bump 30 is formed of aluminum, and the upper layer 32 is formed of BaTiO 3. _Three (Barium titanate: relative dielectric constant εr = 13-15 at 2.45 GHz, tan δ = 10 ^-Four ). In such a configuration, when the microwave MW having a frequency of 2.45 GHz was input from the high-frequency power supply 11, the reflectance was as extremely low as −30 to −25 dB. Therefore, it can be said that this electromagnetic field supply device has high electromagnetic field supply efficiency. By using this electromagnetic field supply apparatus for a plasma processing apparatus, plasma can be generated efficiently.
[0031]
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 microwave MW is TM ₀₁ It may be a mode.
[0032]
Further, although the RLSAs 12 and 12A have been described as an example of the slot antenna, the present invention is not limited to this, and 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.
[0033]
【The invention's effect】
As described above, the electromagnetic field supply apparatus of the present invention uses a cylindrical waveguide instead of the conventional coaxial waveguide. Generally, a cylindrical waveguide has a larger characteristic impedance than a coaxial waveguide. Therefore, by using a cylindrical waveguide, wall current can be reduced, and transmission loss due to conversion of transmission power to heat can be reduced. .
Also, by providing bumps that are at least partially formed of a dielectric, the impedance change from the cylindrical waveguide to the waveguide composed of two conductor plates is moderated, and power is reflected at the connection between the two. Can be reduced.
Thus, by reducing the transmission loss and the reflection of electric power, the supply efficiency of the electromagnetic field can be improved.
Further, since the cylindrical waveguide does not have an inner conductor, abnormal discharge due to overheating of the inner conductor does not occur. For this reason, since it is not necessary to provide a complicated structure such as a cooling mechanism in order to prevent abnormal discharge, a stable operation can be obtained at low cost.
[0034]
Further, by rounding the tip of the bump, it is possible to suppress the occurrence of abnormal discharge due to the concentration of the electric field at the tip of the bump. Therefore, more stable operation can be obtained.
In addition, by providing a tapered portion at the connection portion between the cylindrical waveguide and the waveguide constituted by two conductor plates, the impedance change from the cylindrical waveguide to the waveguide is further moderated. The reflection of power can be further reduced, and the supply efficiency of the electromagnetic field can be further improved.
[0035]
Further, by configuring the plasma processing apparatus using the above-described electromagnetic field supply apparatus, it is possible to improve the plasma generation efficiency and obtain a stable operation at low cost.
[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 plan view of a conductor plate serving as a lower surface of the radial waveguide as viewed from the direction of the line II-II ′ in FIG.
FIG. 3 is a conceptual diagram showing a desirable side shape of a bump.
FIG. 4 is a diagram illustrating a configuration example of a circular polarization converter.
FIG. 5 is a conceptual diagram showing a state of propagation of microwaves at a connection portion between a cylindrical waveguide and a radial waveguide.
FIG. 6 is a diagram for explaining the distribution of microwaves in a radial waveguide.
FIG. 7 is a cross-sectional view showing a modification of a bump.
FIG. 8 is a cross-sectional view showing a modified example of a bump.
FIG. 9 is a plan view showing a modified example of bumps.
FIG. 10 is a cross-sectional view showing the main configuration of a second embodiment of the present invention.
FIG. 11 is a diagram showing a configuration example of a conventional plasma processing apparatus.
[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, 12A ... radial line slot antenna, 13 ... cylindrical waveguide, 14 ... circular polarization converter, 14A, 14B ... stub, 15 ... matching device, 21 ... radial waveguide, 22, 22A, 23 ... Circular conductor plate, 24 ... Ring member, 25 ... Opening, 26 ... Slot, 27, 30, 40, 50, 60, 70 ... Bump, 28 ... Post, 31, 41 ... Lower layer, 32, 42 ... upper layer, 33 ... bolt, 34, 62 ... metal thin film, 51, 53 ... layer made of metal, 52, 54 ... layer made of dielectric, 61 ... bump body, 71, 73, 75, 77 ... Parts made of metal, 72, 74, 76, 78 Portion formed of a dielectric, 81 ... tapered portion, E ... electric field, a strong portion of F ... field intensity, MW ... microwave, P ... plasma.

Claims (6)

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 bump provided on said first conductive plate on protrudes toward the opening of the second conductive plate and at least part of which is formed of a dielectric,
2. The electromagnetic field supply device according to claim 1, wherein the bump has a multilayer structure in which layers made of metal and layers made of a dielectric are alternately arranged . The electromagnetic field supply device according to claim 1,
2. The electromagnetic field supply device according to claim 1, wherein the bump has a two-layer structure including a lower layer made of metal and an upper layer made of a dielectric. The electromagnetic field supply device according to claim 1,
2. The electromagnetic field supply device according to claim 1, wherein the bump has a two-layer structure including an upper layer made of metal and a lower layer made of a dielectric. In the electromagnetic field supply device according to any one of claims 1 to 3 ,
The electromagnetic field supply device according to claim 1, wherein a tip of the bump toward the opening is rounded. In the electromagnetic field supply device according to any one of claims 1 to 4 ,
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 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 1-5 , The plasma processing apparatus characterized by the above-mentioned.

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