TW201345325A - Microwave irradiating antenna, microwave plasma source, and plasma processing device - Google Patents

Abstract

A microwave radiation antenna (45) for irradiating microwaves propagated over a microwave propagation path into a chamber and generating a surface wave plasma has: an antenna unit (121) comprising a conductor; a plurality of slots (122) through which microwaves are irradiated, the slots (122) being provided in the antenna unit (121); and a plurality of gas discharge apertures (125) for discharging a processing gas into the chamber, the gas discharge apertures (125) being provided in the antenna unit (121). A dielectric layer (126) is provided so that a metallic surface wave is formed on a surface by the microwaves, a surface wave plasma is generated by the metallic surface wave, and at least a portion of the metallic surface of the antenna unit (121) is insulated in terms of direct current from the surface wave plasma.

Description

Microwave radiation antenna, microwave plasma source and plasma processing device

The invention relates to a microwave radiation antenna, a microwave plasma source and a plasma processing device.

In recent years, the demand for the manufacture of semiconductor devices for plasma processing is indispensable. In recent years, the design rules for semiconductor devices constituting LSIs have become increasingly finer due to the demand for integration and higher speed of LSIs, and semiconductor wafers have become larger. Along with this, the plasma processing apparatus is also required to be finer and larger in size.

However, in the conventional parallel plate type or inductively coupled plasma processing apparatus, since the generated electron temperature of the plasma is high, plasma damage is caused to the fine components, and since it is limited to a high plasma density. The area makes it difficult to homogenize large semiconductor wafers and perform plasma processing at high speed.

Therefore, an RLSA (Radial Line Slot Antenna) microwave plasma processing apparatus which can uniformly generate a surface wave plasma having a low electron temperature at a high density has been attracting attention (for example, Patent Document 1).

The RLSA microwave plasma processing apparatus is provided with a microwave radiation antenna for radiating microwaves for generating surface wave plasma, and a radial groove for a planar slot antenna having a plurality of slots formed in a predetermined pattern in the upper portion of the chamber. Radial Line Slot Antenna, which radiates microwaves guided from a microwave plasma source from a slot of an antenna and is radiated to a vacuum through a microwave penetrating plate formed by a dielectric body disposed thereunder. In the chamber, surface wave plasma is generated in the chamber by the microwave electric field, and the object to be processed such as a semiconductor wafer is processed.

Further, there is also a plasma processing apparatus which is configured to distribute microwaves into a plurality of microwave radiation sections having a planar slot antenna having the above-described microwave radiation antenna, and to introduce microwaves radiated from the planar slot antennas. Microwaves are synthesized in the chamber to generate plasma in the chamber (Patent Document 2).

[Previous Technical Literature]

Patent Document 1: Japanese Laid-Open Patent Publication No. 2000-294550

Patent Document 2: International Publication No. 2008/013112

However, in the processing apparatuses described in Patent Documents 1 and 2, the microwave is introduced from the top wall of the chamber, and the processing gas is supplied from the side wall of the chamber or the shower plate provided in the chamber. However, such conditions can make it difficult to control the flow of gas. In addition, the shower plate must be formed of quartz with plasma resistance. Since the microwave will pass through the quartz, there will be gas plasma at the gas hole of the shower plate, and the microwave power is lost or abnormal discharge is generated. Happening.

In order to prevent such a problem, it is conceivable that the microwave radiating antenna made of metal (conductor) has a gas hole shower structure, and the microwave and the gas are introduced from the same portion. In this case, since the gas is radiated by the microwave radiation antenna made of metal, the gas is ejected by the presence of the shower plate without being affected by the microwave, and a metal surface wave plasma can be formed on the surface of the planar slot antenna.

However, in the case where the surface on which the microwave is radiated is made of metal, the plasma concentrates on the periphery of the slot, and it is found that the uniformity of the radial direction is disturbed.

Accordingly, an object of the present invention is to provide a microwave radiation antenna, a microwave plasma source, and a plasma processing apparatus which can supply microwaves and processing gases from a microwave radiation antenna to form a surface wave plasma having high uniformity on the surface.

That is, according to a first aspect of the present invention, a microwave radiation antenna is provided in a plasma processing apparatus that forms a surface wave plasma in a chamber and performs plasma processing, and outputs the microwave output unit to a microwave transmission path. The microwave radiation antenna radiated into the chamber has: an antenna body composed of a conductor; a plurality of slots provided in the antenna body to radiate microwaves; and a antenna body disposed to discharge the processing gas into the chamber a plurality of gas ejection holes; and a microwave surface wave is formed on the surface by the microwave, thereby generating surface wave plasma by the metal surface wave; and at least a portion of the metal surface of the antenna body is subjected to DC from the surface wave plasma The ground insulation method is constructed.

In the above first aspect, at least a part of the surface of the antenna body is insulated by covering with a dielectric layer capable of maintaining the thickness of the metal surface wave. In this case, preferably, the thickness of the dielectric layer is λ/7 or less when the microwave wavelength in the vacuum is λ.

The dielectric layer may be a film formed by a film forming technique or a dielectric thin plate. In the case of using a dielectric thin plate, preferably, the dielectric thin plate has a metal film having a pattern in which the groove and the gas ejection hole are removed in a part of the opposing surface of the antenna body. This situation Preferably, the plurality of slots are circumferentially disposed on the surface of the antenna body, and the metal film is disposed at a position ranging from a center of the dielectric sheet to an outer diameter of the slot. Also, the antenna body can be insulated from the chamber by DC.

According to a second aspect of the present invention, a microwave plasma source is provided, which is a microwave plasma source that radiates microwaves into a chamber of a plasma processing apparatus to form a surface wave plasma, and has a microwave output unit that generates microwaves and outputs the microwaves. And a microwave supply unit for supplying microwaves output from the microwave output unit to the chamber; the microwave supply unit includes: a transmission path for transmitting microwaves output from the microwave output unit; and microwaves a microwave radiation antenna radiated into the chamber; the microwave radiation antenna having: an antenna body formed of a conductor; a plurality of slots provided in the antenna body to radiate microwaves; and a antenna body disposed on the antenna body to discharge the processing gas to the antenna a plurality of gas ejection holes in the chamber; and a microwave surface wave is formed on the surface by the microwave, thereby generating a surface wave plasma by the metal surface wave, and at least a portion of the metal surface of the antenna body is from the surface wave plasma It is constructed by DC insulation.

According to a third aspect of the present invention, a plasma processing apparatus includes: a chamber that houses a substrate to be processed; a gas supply mechanism that supplies a processing gas; and a microwave that radiates into the chamber to form a surface wave plasma a microwave plasma source; the microwave plasma source is provided with: a microwave output portion for generating microwaves; and a microwave supply portion for supplying microwaves outputted from the microwave output portion to the chamber; the microwave supply portion The present invention includes: a transmission path for transmitting microwaves output from the microwave output unit; and a microwave radiation antenna for radiating microwaves into the chamber; the microwave radiation antenna having: an antenna body formed of a conductor; a plurality of slots for radiating microwaves in the body; and a plurality of gas ejection holes provided in the antenna body to eject the processing gas into the chamber; and the surface waves are formed on the surface by the microwaves, thereby generating a surface by the surface waves of the metal Wave plasma, and at least a portion of the metal surface of the antenna body is constructed by DC-insulating the surface wave plasma; a surface wave generated on the surface of the microwave radiation antenna by microwaves supplied from the microwave plasma source into the chamber to generate surface wave plasma of the gas supplied from the gas supply mechanism, and plasma The substrate to be processed in the chamber is treated.

In the second and third aspects described above, the microwave supply unit may have a plurality of microwave radiation antennas.

1‧‧‧ chamber

2‧‧‧Microwave plasma source

11‧‧‧crystal seat

12‧‧‧Support members

15‧‧‧Exhaust pipe

16‧‧‧Exhaust device

17‧‧‧ moving out of the entrance

30‧‧‧Microwave Output Department

31‧‧‧Microwave power supply

32‧‧‧Microwave Oscillator

40‧‧‧Microwave Supply Department

41‧‧‧Antenna Module

42‧‧‧Increase

43‧‧‧Microwave Radiation Department

44‧‧‧ Guided path (microwave transmission path)

45‧‧‧Microwave radiation antenna

52‧‧‧Outer conductor

53‧‧‧Inside conductor

54‧‧‧Power supply agency

55‧‧‧Microwave electric power introduction埠

60‧‧‧ Tuner

82‧‧‧ Slow wave material

85‧‧‧ top board

100‧‧‧ Plasma processing unit

110‧‧‧ gas supply

111‧‧‧ gas piping

121‧‧‧Antenna body

122‧‧‧Slots

123‧‧‧ gas diffusion space

125‧‧‧ gas ejection holes

126‧‧‧Dielectric layer (dielectric thin plate)

130‧‧‧ gap

131‧‧‧Metal film

140‧‧‧Control Department

W‧‧‧Semiconductor Wafer

1 is a view showing a microwave plasma having a microwave radiation antenna according to an embodiment of the present invention. A cross-sectional view of a schematic configuration of a source plasma processing apparatus.

Fig. 2 is a view showing the configuration of a microwave plasma source used in the plasma processing apparatus of Fig. 1.

Fig. 3 is a plan view schematically showing a microwave supply unit in a microwave plasma source.

Fig. 4 is a longitudinal sectional view showing a microwave radiation portion including a microwave radiation antenna used in the plasma processing apparatus of Fig. 1.

Fig. 5 is a cross-sectional view showing the AA' line of Fig. 4 of the power supply mechanism of the microwave radiating portion.

Fig. 6 is a cross-sectional view showing the slag in the tuner and the BB' line of Fig. 4 of the sliding material.

Fig. 7 is a cross-sectional view showing the CC' line of Fig. 4 inside the microwave radiation antenna.

Fig. 8 is a plan view showing an example of the shape and arrangement of the slots of the microwave radiating antenna.

Fig. 9 is a view showing a case where the surface of the microwave radiating antenna is a metal (conductor), and a difference in thickness of the sheath portion between the slot portion and the portion other than the slot.

Fig. 10 is a view showing the thickness of the sheath portion at the portion of the slot where the dielectric layer is provided on the surface of the microwave radiating antenna and the portion outside the slot.

Fig. 11 is a view showing a state of a surface wave plasma in a case where a dielectric layer is not formed in an antenna body of a microwave radiation antenna and a state in which it is formed.

Fig. 12 is a view showing an electron density distribution in a case where a dielectric layer is not formed in an antenna body of a microwave radiation antenna and a case where it is formed.

Fig. 13 is a view showing an electron density distribution pattern normalized by the electron density at a position where the radial distance of Fig. 12 is zero.

Fig. 14 is a view for explaining the mechanism of abnormal discharge generated in the gap between the antenna body and the dielectric thin plate in the case where a dielectric thin plate is used as the dielectric layer.

Fig. 15 is a view showing an electric field portion of a gap between an antenna body and a dielectric thin plate obtained by electromagnetic field simulation.

Fig. 16 is a view showing a portion of an electric field portion in which a gap between an antenna body and a dielectric thin plate obtained by electromagnetic field simulation is performed by coating a metal film on a surface of a dielectric thin plate opposite to an antenna body.

Fig. 17 is a view schematically showing a state in which a metal film formed on a dielectric thin plate is formed in an inner region of a slot of a dielectric thin plate.

Fig. 18 is a view showing the electric field portion of the gap between the antenna body and the dielectric thin plate obtained by electromagnetic field simulation using the dielectric thin plate in which the metal film is formed in the state of Fig. 17; formula.

Fig. 19 is a view schematically showing a state in which a metal film formed on a dielectric thin plate is aligned with an inner region of a slot of a dielectric thin plate and an outermost periphery is aligned with an outer diameter of the slot.

Fig. 20 is a view showing a portion of an electric field portion of a gap between an antenna body and a dielectric thin plate obtained by electromagnetic field simulation using a dielectric thin plate in which a metal film is formed in the state of Fig. 19.

Figure 21 is a cross-sectional view showing an example of a preferred microwave antenna in the case of a dielectric thin plate.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

<Composition of plasma processing device>

1 is a cross-sectional view showing a schematic configuration of a plasma processing apparatus including a microwave plasma source of a microwave radiation antenna according to an embodiment of the present invention, and FIG. 2 is a view showing a microwave plasma source used in the plasma processing apparatus of FIG. FIG. 3 is a plan view showing a microwave supply unit in a microwave plasma source, FIG. 4 is a cross-sectional view showing a microwave radiation portion of a microwave radiation antenna including a microwave plasma source, and FIG. 5 is a view showing a microwave radiation portion. FIG. 6 is a cross-sectional view of the AA' line of FIG. 4 of the power supply mechanism, and FIG. 6 is a cross-sectional view showing the slag and the BB' line of the sliding material in the tuner of the microwave radiation portion, and FIG. 7 is a view showing the microwave radiation portion. A cross-sectional view of the CC' line of FIG. 4 of the microwave radiation antenna.

The plasma processing apparatus 100 is configured as a plasma etching apparatus which applies a plasma treatment to a wafer, for example, an etching treatment, and has a cylindrical ground chamber 1 composed of a metal material such as aluminum or stainless steel which is hermetically sealed, and A microwave plasma source 2 for forming microwave plasma in the chamber 1. An opening 1a is formed in an upper portion of the chamber 1, and the microwave plasma source 2 is disposed from the opening 1a facing the inside of the chamber 1.

The inside of the chamber 1 is provided with a semiconductor wafer W (hereinafter referred to as wafer W) for supporting the object to be processed in a state of being supported by the cylindrical support member 12 which is erected in the center of the bottom of the chamber 1 through the insulating member 12a. The crystal seat 11 supported by the ground. The material constituting the crystal seat 11 and the support member 12 is exemplified by aluminum whose surface is subjected to an alumite treatment (anodizing treatment) or a ceramic such as AlN.

Further, although not shown, the crystal holder 11 is provided with an electrostatic chuck for electrostatically adsorbing the wafer W, a temperature control mechanism, a gas flow path for supplying heat transfer gas to the inner surface of the wafer W, and a gas flow path for Lifting the lifting and lowering of the wafer W. Furthermore, the crystal holder 11 is electrically connected through the matching unit 13 High frequency bias power supply 14. By supplying high frequency electric power from the high frequency bias power source 14 to the crystal stage 11, ions in the plasma are attracted to the wafer W side. In addition, the high frequency bias power supply 14 may not be provided depending on the characteristics of the plasma treatment.

An exhaust pipe 15 is connected to the bottom of the chamber 1, and the exhaust pipe 15 is connected to an exhaust device 16 including a vacuum pump. Then, by operating the exhaust device 16, the inside of the chamber 1 is exhausted, and the inside of the chamber 1 can be decompressed at a high speed to a predetermined degree of vacuum. Further, a side wall of the chamber 1 is provided with a carry-out port 17 for carrying in and out of the wafer W, and a gate valve 18 for opening and closing the carry-out port 17.

The microwave plasma source 2 is provided on a top plate 85 supported by a support ring 29 provided on the upper portion of the chamber 1. The support ring 29 and the top plate 85 are hermetically sealed.

The microwave plasma source 2 has a microwave output unit 30 that distributes microwaves distributed in a plurality of channels, and a microwave supply unit 40 that transmits microwaves output from the microwave output unit 30 and radiates into the chamber 1. Further, the microwave plasma source 2 has a gas supply source 110 for supplying a plasma generating gas for generating plasma or a processing gas for performing a film forming process or an etching process.

The plasma generating gas can be applied to a rare gas such as an Ar gas. Further, the processing gas may be various gases in accordance with processing contents such as a film forming process or an etching process.

As shown in FIG. 2, the microwave output unit 30 includes a microwave plasma source 31, a microwave oscillator 32, an amplitude booster 33 for amplifying the microwave after oscillation, and a distributor 34 for distributing the amplified microwaves into a plurality.

The microwave oscillator 32 is such that a microwave of a predetermined frequency (for example, 915 MHz) is oscillated by, for example, a PLL. The distributor 34 is configured to obtain impedance matching between the input side and the output side in such a manner as not to cause microwave loss as much as possible, and to distribute the microwaves amplified by the amplifier 3. In addition, the frequency of the microwave can be 700 MHz to 3 GHz in addition to 915 MHz.

The microwave supply unit 40 has a plurality of antenna modules 41 that introduce microwaves distributed by the distributor 34 into the chamber 1. Each of the antenna modules 41 has an amplification unit 42 that mainly increases the distributed microwaves, and a microwave radiation unit 43. Further, as will be described later, the microwave radiating portion 43 has a microwave transmission path 44 in which the tuner 60 for matching the impedance is provided, and an antenna 45 that radiates the amplified microwave into the chamber 1. Then, the microwaves are radiated toward the chamber 1 from the antenna 45 of the microwave radiation portion 43 of each antenna module 41. As shown in FIG. 3, the microwave supply unit 40 has seven antenna modules 41, and the microwave radiation portions 43 of the antenna modules 41 are arranged in a circular shape in a horizontal arrangement and one in the center. The top plate 85.

The antenna 45 is a shower structure in which a plasma generating gas or a processing gas is ejected as will be described later, and a gas pipe 111 extending from the gas supply source 110 is connected to the antenna 45. Then, the plasma generating gas introduced into the chamber 1 from the antenna 45 is plasmad by the microwave radiated from the antenna 45, whereby the plasma is excited and introduced into the chamber 1 from the antenna 45 in the same manner. The process gas is used to produce a plasma of the process gas.

The amplification unit 42 has a phaser 46, a variable gain amplifier 47, a main amplifier 48 constituting a solid-state amplifier, and an isolator 49.

The phaser 46 is configured to change the phase of the microwave, and by adjusting this, the radiation characteristics can be adjusted. For example, by adjusting the phase according to each antenna module, the directivity can be controlled to change the plasma distribution. Moreover, in the adjacent antenna module, a circular depolarization wave can be obtained by shifting the phase of each phase by 90°. Further, the phaser 46 can be used as a delay characteristic between the members of the adjuster for spatial synthesis in the tuner. However, it is not necessary to provide the phaser 46 in the case where the change in the radiation characteristics or the delay adjustment between the members in the amplifier is not required.

The variable gain amplifier 47 adjusts the number of electrical power levels of the microwaves input to the main amplifier 48 as an amplitude adjuster for adjusting the difference or plasma intensity adjustment of each antenna module. By varying the variable gain amplifier 47 depending on the antenna modules, it is also possible to form a distribution in the generated plasma.

The main amplifier 48 constituting the solid state amplifier may be configured to have, for example, an input matching circuit, a semiconductor amplifying element, an output matching circuit, and a high Q resonance circuit.

The isolator 49 is separated by the reflected microwaves reflected by the antenna 45 and directed toward the main amplifier 48, and has a circulator and a simulated load (coaxial terminator). The circulator will direct the microwave reflected by the antenna 45 toward the simulated load, and the simulated load will convert the reflected microwave guided by the circulator into heat.

Next, the microwave radiation portion 43 will be described in detail with reference to Figs. 4 to 7 .

As shown in FIG. 4, the microwave radiation portion 43 has a waveguide path (microwave transmission path) 44 that transmits a coaxial structure of microwaves, and an antenna 45 that radiates microwaves transmitted to the microwave transmission path 44 into the chamber 1. Then, the microwaves radiated from the antenna 45 into the chamber 1 are combined in the space inside the chamber 1, and surface wave plasma is formed in the chamber 1.

The microwave transmission path 44 is configured such that a cylindrical outer conductor 52 and a rod-shaped inner conductor 53 provided at the center thereof are disposed coaxially, and an antenna 45 is provided at the front end of the microwave transmission path 44. In the microwave transmission path 44, power is supplied to the inner conductor 53, and the outer conductor 52 is grounded. A reflector 58 is attached to the upper ends of the outer conductor 52 and the inner conductor 53.

A power supply mechanism 54 for supplying microwaves (electromagnetic waves) is provided on the base end side of the microwave transmission path 44. The power supply mechanism 54 has a microwave electric power introduction port 55 for introducing microwave electric power provided on the side surface of the microwave transmission path 44 (outer conductor 52). The microwave electric power introduction port 55 is connected to a coaxial line 56 composed of an inner conductor 56a and an outer conductor 56b as a power supply line for supplying microwaves amplified from the amplification unit 42. Then, the front end of the inner conductor 56a of the coaxial line 56 is connected to a power supply antenna 90 that extends horizontally toward the inside of the outer conductor 52.

The power feeding antenna 90 is formed, for example, by cutting a metal plate such as aluminum and then inserting it into a mold of a dielectric member such as Teflon (registered trademark). A diffusing material 59 composed of a dielectric body such as Teflon (registered trademark) for shortening the effective wavelength of the reflected wave is provided between the reflecting plate 58 and the feeding antenna 90. Further, in the case of using a high microwave of a frequency of 2.45 GHz or the like, the slow wave material 59 may not be provided. At this time, by optimizing the distance from the power supply antenna 90 to the reflection plate 58, and reflecting the electromagnetic wave reflected from the power supply antenna 90 by the reflection plate 58, the maximum electromagnetic wave is transmitted to the microwave transmission path 44 of the coaxial structure. .

The power supply antenna 90 has an inner conductor 56a connected to the coaxial line 56 in the microwave electric power introduction port 55, and has a first pole 92 for supplying electromagnetic waves and electromagnetic waves to be supplied, as shown in FIG. 5 of the AA' cross-sectional view of FIG. The antenna main body 91 of the second pole 93 to be radiated and the reflection portion 94 extending from the both sides of the antenna main body 91 along the outer side of the inner conductor 53 to form an annular reflection portion 94 are configured to be electromagnetic waves incident on the antenna main body 91 and reflected The electromagnetic waves reflected by the portion 94 form a standing wave. The second pole 93 of the antenna main body 91 is in contact with the inner conductor 53.

When the microwave (electromagnetic wave) is reflected by the power supply antenna 90, the microwave electric power is supplied between the outer conductor 52 and the inner conductor 53. Then, the microwave electric power supplied to the power supply mechanism 54 is transmitted to the antenna 45.

Further, the microwave transmission path 44 is provided with a tuner 60. The tuner 60 is configured to match the load (plasma) impedance in the chamber 1 to the characteristic impedance of the microwave power source of the microwave output unit 30, and has a microwave transmission path 44 that moves up and down between the outer conductor 52 and the inner conductor 53. The two slags 61a and 61b and the slag material driving unit 70 provided on the outer side (upper side) of the reflecting plate 58.

In the slag, the slag 61a is provided on the side of the slag drive unit 70, and the slag 61b is provided on the side of the antenna 45. Further, the inner space of the inner conductor 53 is provided with two slag moving shafts 64a, 64b for moving the slag formed by, for example, a screw having a trapezoidal screw, along the longitudinal direction thereof.

As shown in Fig. 6 of the BB' cross-sectional view of Fig. 4, the slag 61a is an annular shape formed of a dielectric body. A sliding material 63 made of a resin having slip properties is embedded in the inner side. The sliding material 63 is provided with a screw hole 65a to which the slag moving shaft 64a is screwed and a through hole 65b through which the slag moving shaft 64b is inserted. On the other hand, the slag 61b has a screw hole 65a and a through hole 65b similarly to the slag 61a. However, contrary to the slag 61a, the screw hole 65a is screwed to the slag moving shaft 64b, and the through hole 65b is provided. The slag moving shaft 64a penetrates. Thereby, the slag 61a moves up and down by rotating the slag moving shaft 64a, and the slag 61b moves up and down by rotating the slag moving shaft 64b. That is, the slag 61a, 61b moves up and down by the screw mechanism formed by the slag moving shafts 64a, 64b and the sliding material 63.

The inner conductor 53 is formed with three slits 53a at equal intervals in the longitudinal direction. On the other hand, the sliding material 63 is provided with three protruding portions 63a at equal intervals corresponding to the slits 53a. Then, the sliding members 63 are fitted into the interior of the slags 61a, 61b in a state in which the projections 63a are in contact with the inner periphery of the slags 61a, 61b. The outer peripheral surface of the sliding material 63 is in contact with the inner peripheral surface of the inner conductor 53 without a gap, and by the rotation of the slag moving shafts 64a, 64b, the sliding material 63 is slid and moved up and down on the inner conductor 53. That is, the inner peripheral surface of the inner conductor 53 has a slip guiding function of the slags 61a, 61b.

The resin material constituting the sliding material 63 is a resin which has good slip property and is easy to process, and preferably, for example, a polyphenylene sulfide (PPS) resin.

The slag moving shafts 64a, 64b extend through the reflecting plate 58 and extend to the slag driving portion 70. A bearing (not shown) is provided between the slag drive shafts 64a, 64b and the reflector 58. Further, a bottom plate 67 composed of a conductor is provided at the lower end of the inner conductor 53. The lower ends of the slag moving shafts 64a, 64b are generally open ends for absorbing vibration during driving, and are provided with a bottom plate 67 away from the lower ends of the slag moving shafts 64a, 64b by about 2 to 5 mm. Alternatively, the bottom plate 67 may be used as a bearing to support the lower ends of the moving shafts 64a, 64b by the bearings.

The slag material driving unit 70 has a casing 71, and the slag moving shafts 64a and 64b extend in the casing 71, and gears 72a and 72b are assembled to the upper ends of the slag moving shafts 64a and 64b, respectively. Further, the slag material driving unit 70 is provided with a motor 73a that rotates the slag moving shaft 64a and a motor 73b that rotates the slag moving shaft 64b. A gear 74a is assembled to the shaft of the motor 73a, a gear 74b is assembled to the shaft of the motor 73b, the gear 74a is meshed with the gear 72a, and the gear 74b is meshed with the gear 72b. Therefore, the slag moving shaft 64a is rotated by the motor 73a passing through the gears 74a and 72a, and the slag moving shaft 64b is rotated by the motor 73b passing through the gears 74b and 72b. Further, the motors 73a and 73b are, for example, stepping motors.

Further, the slag moving shaft 64b is longer than the slag moving shaft 64a and reaches the upper portion, so that the positions of the gears 72a and 72b are shifted up and down, and the motors 73a and 73b are also shifted up and down, When the space of the power transmission mechanism such as the motor and the gear is small, the casing 71 has the same diameter of the outer conductor 52.

The motors 73a and 73b are provided with incremental encoders 75a and 75b for detecting the positions of the slags 61a and 61b, respectively, by directly connecting the output shafts.

The positions of the slags 61a and 61b are controlled by the slag controller 68. Specifically, based on the input impedance values detected by the impedance detector not shown, and the position information of the slags 61a and 61b detected by the encoders 75a and 75b, the slag controller 68 will The control signal is transmitted to the motors 73a and 73b, and the impedance is adjusted by controlling the positions of the slags 61a and 61b. The slag material controller 68 performs impedance matching in such a manner that the terminal will become, for example, 50 Ω. When only one of the two slags is moved, the trajectory through the Smith chart origin is drawn, and when both sides move simultaneously, only the phase is rotated.

The antenna 45, which is a microwave radiating antenna, is configured as a planar slotted antenna having a planar shape and having a slot. A slow wave material 82 is disposed on the antenna 45. The center of the slow wave material 82 is inserted through a cylindrical member 82a composed of a conductor, and the cylindrical member 82a is connected to the bottom plate 67 and the antenna 45. Therefore, the inner conductor 53 is connected to the antenna 45 through the bottom plate 67 and the cylindrical member 82a. Further, the lower end of the outer conductor 52 extends to the antenna 45, and the periphery of the slow-wave material 82 is covered by the outer conductor 52.

The slow wave material 82 has a dielectric constant larger than that of a vacuum, and is made of, for example, a fluorine-based resin such as quartz, ceramic, or polytetrafluoroethylene or a polyimide resin. This is because the wavelength of the microwave in the vacuum becomes longer, so the wavelength of the microwave is shortened to make the antenna smaller. The slow wave material 82 can adjust the phase of the microwave by the thickness thereof, and adjust the thickness of the surface of the antenna 45 (the microwave radiation surface) so as to become the "antinode" of the standing wave. Thereby, the minimum reflection can be made to maximize the radioactivity of the microwave.

As shown in FIG. 4, the antenna 45 has an antenna body 121 which is formed in a hollow disk shape, and is formed in the antenna body 121 for radiating microwaves transmitted from the microwave transmission path 44 to the plurality of slots 122 in the chamber 1. a gas diffusion space 123 formed inside the antenna body 121; a gas introduction port 124 for introducing a plasma generating gas or a processing gas into the gas diffusion space 123; and a plurality of gas ejection holes extending from the gas diffusion space 123 toward the chamber 1 And a dielectric layer 126 formed on a microwave radiating surface of the antenna body 121. An O-ring (not shown) is interposed between the slow wave material 82 and the antenna body 121.

The antenna body 121 is formed of an electrical conductor. Preferably, the conductor constituting the antenna body 121 is an example. High electrical conductivity metal such as aluminum or copper. The antenna body 121 has an upper wall 121a, a side wall 121b, and a bottom wall 121c.

The gas introduction port 124 is provided on the outer peripheral side of the slot 122 of the upper wall 121a, and is connected to the gas pipe 111 extending from the gas supply source 110, and is supplied to the gas pipe 111 from the gas supply source 110. The slurry generating gas or a processing gas such as a C ₄ F ₈ -like fluorinated carbon gas is introduced into the gas diffusion space 123 through the gas introduction port 124. The gas ejection hole 125 is formed in the bottom wall 121c, and the gas introduced into the gas diffusion space 123 is ejected into the chamber 1.

The slot 122 has an upper portion 122A formed through the gas diffusion space 123 from the upper wall 121a and a lower portion 122B formed through the bottom wall 121c. The portion corresponding to the gas diffusion space 123 in the upper portion 122A of the slot 122 is as shown in Fig. 7 of the CC' cross-sectional view of Fig. 4, and is formed with a partition portion 127 which partitions the gas diffusion space 123. Thereby, the microwave passing through the slot 122 is separated from the gas flowing through the gas diffusion space 123 to avoid generation of plasma inside the antenna 45.

A step described later is formed between the upper portion 122A and the lower portion 122B. The slot 122 may also be filled with a dielectric body. By filling the dielectric hole in the slot 122, the effective wavelength of the microwave is shortened, and the thickness of the entire slot (the thickness of the antenna body 121) can be made thin.

The shape of the slot 122 of the microwave radiating surface which determines the radiation characteristics of the slot 122 is as shown in Fig. 8, for example. Specifically, four slots 122 are equally formed in such a manner that the overall shape is a circumferential shape. The slots 122 are all of the same shape and are formed in an elongated shape along the circumference. The slots 122 are symmetrically arranged with respect to the center O of the microwave radiating surface of the antenna body 121.

The circumferential length of the slot 122 is (λg/2)-δ, which is designed such that the peak of the microwave electric field strength will come to the center of the slot 122. Among them, λg is the effective wavelength of the microwave, and δ is a fine adjustment component (including 0) which is finely adjusted so that the electric field intensity uniformity in the circumferential direction (angular direction) is high. Λg can be expressed by the following formula.

Λg=λ/εs ^1/2

Where εs is the dielectric constant of the slot and λ is the microwave wavelength in the vacuum. Further, the length of the slot 122 is not limited to about λg/2, as long as the fine adjustment component (including 0) is subtracted from an integral multiple of λg/2.

The portions of the slots 122 that are adjacent to each other are formed such that the end portions of the slots 122 and the ends of the other slots 122 overlap in the radial direction at regular intervals. Thereby, in the circumferential direction, there is no portion where the groove is not present, and the radiation characteristics in the circumferential direction are designed to be uniform. The slot 122 is divided into three portions of the central portion 122a, the left end portion 122b, and the right end portion 122c in the circumferential direction, and the left end portion 122b and the right end portion 122c are slightly fan-shaped (arc-shaped). They are disposed on the outer peripheral side and the inner peripheral side, respectively, and the central portion 122a is connected to the straight line. Then, the left end portion 122b and the right end portion of the adjacent slot are disposed such that the left end portion 122b is above, and the right end portion 122c and the left end portion of the adjacent slot are disposed such that the right end portion 122c is below. The central portion 122a and the left end portion 122b and the right end portion 122c have a slightly equal length. That is, the central portion 122a has a length of (λg / 6) - δ ₁ , and the left end portion 122b and the right end portion 122c on both sides are (λg / 6) - δ ₂ and (λg / 6) - δ _{3 , respectively.} The length. Among them, δ ₁ , δ ₂ , and δ ₃ are fine adjustment components (including 0) which are finely adjusted so that the electric field intensity uniformity in the circumferential direction (angular direction) becomes high. Since the length of the overlapping portion of the adjacent slots is preferably equal, it is preferably δ ₂ = δ ₃ .

The inner periphery of the slot 122 is formed so as to become the center of the microwave radiating surface (λg/4) ± δ' of the antenna main body 121. Here, δ' is a fine adjustment component (including 0) which is finely adjusted in order to uniformize the electric field intensity distribution in the radial direction. Further, the length from the center to the inner circumference of the slot is not limited to λg/4, and may be an integer multiple of λg/4 plus a fine adjustment component (including 0).

Thus, the antenna 45 is disposed by overlapping the ends of the slots having a lower electric field strength, and the electric field intensity of the portion can be increased. As a result, the electric field intensity distribution in the circumferential direction (angular direction) can be made uniform.

Further, the number of slots is not limited to four, and for example, even if it is five or more, the same effect can be obtained. Further, the shape of the slit is not limited to those shown in Fig. 8, and for example, the other of the plurality of arcuate slits may be uniformly formed on the circumference.

In the upper portion 122A of the slot 122, the interval between the overlapping portion of the left end portion 122b and the right end portion 122c is wider than the interval between the lower portion 122B, and therefore, a step is formed between the upper portion 122A and the lower portion 122B. By thus widening the interval between the overlapping portion of the left end portion 122b and the right end portion 122c in the upper portion 122A, the conductance of the gas in the gas diffusion space 123 can be made large, and the uniformity of the gas flow velocity can be improved.

The dielectric layer 126 is made of a dielectric such as quartz and is used to set the surface of the antenna 45 to the floating potential of the plasma. That is, the surface of the metal (conductor) of the antenna body 121 and the plasma are DC-insulated by the dielectric layer 126. Further, from the viewpoint of preventing abnormal discharge, the entire antenna 45 may be grounded without being grounded. For example, by making the outer conductor 52 Insulation between the antenna 45 and the top plate 85 and the antenna 45 allows the antenna 45 to be insulated from the ground outer conductor 52 and the chamber 1 so as to have a floating potential as a whole.

The dielectric layer 126 has a thickness of λ/7 or less (λ is a microwave wavelength in a vacuum) so that a metal surface wave is formed on the surface of the antenna 45. The dielectric layer 126 may be a mold formed by a film forming technique such as flame spraying, or may be in the form of a plate.

The antenna 45 can also apply a DC voltage. Thereby, the thickness of the sheath region of the metal surface wave formed on the surface of the transmitting antenna 45 can be controlled in the case where the microwave electric power is applied. Thereby, the electron density distribution, the ion density distribution, and the radical density distribution of the plasma can be optimized.

In the present embodiment, the main amplifier 48, the tuner 60, and the antenna 45 are arranged close to each other. Then, the tuner 60 and the antenna 45 constitute a lumped circuit existing in 1/2 wavelength, and the antenna 45 and the slow wave material 82 are set to have a combined impedance of 50 Ω, so the tuner 60 will be plasma. The load is directly tuned to transfer energy efficiently to the plasma.

Each component of the plasma processing apparatus 100 is controlled by a control unit 140 including a microprocessor. The control unit 140 includes a memory unit that stores a program recipe that is a program mechanism and control parameters of the plasma processing apparatus 100, an input unit, a display, and the like, and controls the plasma processing apparatus according to the selected program recipe.

<Operation of Plasma Processing Apparatus>

Next, the operation of the plasma processing apparatus 100 configured as above will be described.

First, the wafer W is carried into the chamber 1 and placed on the wafer holder 11. Then, a plasma generating gas is supplied from the gas supply source 110 through the gas pipe 111, and for example, Ar gas is introduced into the gas diffusion space 123 of the antenna 45, and is ejected from the gas ejection hole 125, and is discharged from the microwave output portion 30 of the microwave plasma source 2. The microwaves transmitted from the amplification unit 42 and the microwave radiation portion 43 of the antenna modules 41 of the microwave supply unit 40 are radiated into the cavity 1 by the slots 122 of the antenna 45, and a metal surface wave is formed on the surface of the antenna 45 to Surface wave plasma is produced. Further, similarly, the process gas introduced from the gas supply source 110 through the gas pipe 111 into the gas diffusion space 123 is ejected from the gas ejection hole 125 into the chamber 1, and is plasma-plasmrated by surface wave plasma excitation, and by The plasma of the process gas is subjected to a plasma treatment, such as an etching process, on the wafer W.

When the surface wave plasma is generated, in the microwave plasma source 2, the microwave electric power oscillated from the microwave oscillator 32 of the microwave output unit 30 is amplified by the amplifier 33, and then distributed to the plural by the distributor 34, and distributed. The microwave electric power is directed toward the microwave supply unit 40. In the microwave supply unit 40, this The microwave electric power that is generally distributed into a plurality of numbers is individually amplified by the main amplifier 48 constituting the solid-state booster, and supplied to the microwave transmission path 44 of the microwave radiation portion 43 to be transmitted to the microwave transmission path 44, and then penetrates the slow wave material. 82 is radiated through the slot 122 of the antenna 45. Then, a metal surface wave is formed in the sheath region formed on the surface of the antenna 45, and surface wave plasma is generated in the space inside the chamber 1 by the surface wave.

In the present embodiment, both the microwave and the gas are introduced into the chamber 1 by the antenna 45 provided in the top plate 85, so that the flow controllability of the gas is good, and the radiation direction of the microwave overlaps with the flow direction of the gas. The gas can be efficiently plasmad.

Further, since the antenna 45 is made of metal (conductor), the microwave does not penetrate, and when the gas passes through the gas diffusion chamber 123 and the gas ejection hole 125, power loss due to gas plasma formation or abnormal discharge does not occur. Happening. Further, in the past, when a shower structure is to be formed by a thick dielectric member (microwave penetrating window) provided on the distal end side of the antenna 45, there is a problem that processing is difficult, in addition to problems such as abnormal discharge. However, in the present embodiment, the gas ejection hole 125 can be easily formed in the metal antenna 45.

However, in the case where the surface wave plasma is formed on the surface of the microwave radiation antenna made of metal, it is known that the plasma concentrates on the periphery of the slot 122 to emit light (generated), and the uniformity of the radial direction is disturbed.

As a result of reviewing the cause, it was found that the thickness of the sheath portion of the portion other than the slot was different. As shown in FIG. 9, the slot portion is a dielectric body and is a floating potential, so as shown in (a), the potential difference from the plasma becomes larger, and the thickness of the sheath region becomes a thickness corresponding to the plasma state ( The ratio is 1/2 of the self-bias voltage Vdc). On the other hand, since the portion other than the slot portion is made of metal and is grounded, as shown in (b), the potential difference from the plasma becomes small, and the sheath region becomes thin. In such a region where the sheath region is thinned, microwave reflection and attenuation occur, and the surface wave is blocked. Therefore, in the part thereof, sufficient surface wave plasma cannot be generated to make the light emission weak. That is, the surface wave plasma cannot be sufficiently diffused to a portion other than the slot portion.

Therefore, in the present embodiment, the dielectric layer 126 is provided on the surface of the antenna 45 of the microwave radiation antenna, so that the portion other than the slot portion also becomes the floating potential with respect to the plasma. That is, by the dielectric layer 126, by insulating the metal (conductor) surface of the antenna main body 121 from the plasma DC, not only the slot portion but also the slot portion is a floating potential. As a result, as shown in FIG. 10, the sheath region of the portion other than the slot portion of the surface of the antenna 45 of (b) becomes thicker, and the thickness of the sheath portion of the slot portion of (a) is the same, so that Blocking metal surface waves, and generating charge Surface wave plasma of the foot. Therefore, the surface wave plasma can also be sufficiently diffused to a portion other than the slot portion to generate a uniform surface wave plasma in the radial direction. Further, since the dielectric body groove 126 is thin, it is easy to process the gas ejection hole or the groove.

As described above, according to the present embodiment, since at least a part of the metal surface of the antenna main body is configured to be insulated from the surface wave plasma by DC, the sheath portion of the insulated portion can be thickened, and the metal surface wave can be prevented from being blocked. The surface wave plasma will diffuse sufficiently, and a surface wave plasma with high uniformity can be generated on the surface.

In addition, the dielectric layer 126 does not have to be formed on the entire surface of the antenna body 121, and may be formed in at least a part.

Actually, a plasma generation experiment in which the dielectric layer 126 is not formed and the case where it is formed has been performed. Here, the dielectric layer 126 is formed as a film, and the plasma generating gas system uses Ar gas to generate plasma under the conditions of a pressure of 0.5 Torr, a microwave electric power of 400 W, and a pressure of 1 Torr and microwave electric power of 100 W and 125 W.

The results are shown in Figs. 11 to 13 . 11 shows the state of light emission of the plasma. When the dielectric layer 126 is not formed, as shown in (a), the surface wave plasma is not sufficiently diffused, whereas the dielectric layer 126 is formed. In the case, as shown in (b), it is known that the surface wave plasma is sufficiently diffused. Further, Fig. 12 is a diagram in which the radial distance is the horizontal axis, the electron density is the vertical axis, and the electron density distribution is shown, and Fig. 13 shows the electron density at the position where the radial distance of Fig. 12 is zero. Normalized electron density distribution pattern. As can be seen from the figures, by providing the dielectric layer 126, the surface wave plasma is diffused, and a more uniform electron density distribution can be obtained.

However, it is not always easy to form a film such as quartz into a metal by flame spraying or the like. On the other hand, it is relatively easy to use a dielectric thin plate as the dielectric layer 126. Therefore, in terms of manufacturing, a dielectric thin plate is preferably used as the dielectric layer 126.

However, when a dielectric thin plate is used as the dielectric layer 126, a small gap (about 0.3 to 0.5 mm) between the antenna main body 121 and the dielectric thin plate is inevitably caused, and it is known that abnormal discharge occurs in the gap. . When an abnormal discharge is generated, the electric power transmission effect to the plasma is remarkably lowered.

In order to understand the cause of such abnormal discharge, the electromagnetic field simulation analysis of the dielectric thin plate was performed. As a result, when the dielectric thin layer is used as the dielectric layer 126, in the case where the microwave electric power is supplied, as shown in FIG. 14, the TE ₁₀ wave is transmitted to the gap between the antenna main body 121 and the dielectric thin plate 126. 130, as shown in FIG. 15, especially in the inner region of the plurality of slots 122, the electric field becomes strong, and abnormal discharge is likely to occur.

In order to attenuate such a TE ₁₀ wave, it is considered that a metal film is coated on the opposite surface of the dielectric thin plate and the antenna body 121.

However, in the case where the metal film is covered on the entire surface except for the slot 122 and the gas ejection hole 125 of the dielectric thin plate, according to the electromagnetic field simulation analysis, as shown in FIG. 16, the antenna body 121 and the dielectric thin plate 126 are as shown in FIG. The electric field in the gap will become higher. This should be because when the metal film is applied over the entire surface, the effect of microwave reflection will become larger.

Therefore, in the case where a dielectric thin plate is used as the dielectric layer 126, a metal film is applied to a portion of the dielectric thin plate 126 opposite to the antenna body 121.

Next, the pattern when the metal film is covered is reviewed.

As shown in Fig. 17, the metal film was applied to the central portion of the dielectric thin plate 126 (the inner region of the slot 122), and the electromagnetic field simulation analysis was performed. As shown in Fig. 18, the antenna body was confirmed. The electric field between the 121 and the dielectric thin plate 126 may become lower. However, in the case of FIG. 17, since the metal film exists in the vicinity of the outer diameter of the upper portion 122A of the lower portion 122B of the microwave radiating portion of the slot 122, the electric field of the slot portion becomes high. There is a concern about abnormal discharge at the slot portion.

Here, as shown in FIG. 19, as a result of optimization of the outer diameter of the lower portion 122B of the microwave radiating portion of the slot 122, the result of the electromagnetic field simulation analysis is as shown in FIG. The electric field of the slot portion is moderated, and the possibility of abnormal discharge is lowered.

Therefore, as shown in FIG. 21, in the opposing surface of the dielectric thin plate 126 and the antenna main body 121, the metal film 131 is preferably coated from the center to the outer diameter of the slot 122. Thereby, abnormal discharge of the gap 130 between the antenna body 121 and the dielectric thin plate 126 can be suppressed.

At this time, the method of forming the metal film 131 is not particularly limited as long as it is a film forming technique, but flame spraying is preferably used. Further, the thickness of the metal film 131 is preferably 5 to 150 μm.

<Other applicable>

Further, the present invention is not limited to the above embodiment, and various modifications are possible within the scope of the inventive concept. For example, the configuration of the microwave output unit 30 or the microwave supply unit 40 is not limited to the above embodiment. For example, when it is not necessary to perform microwave pointing control from the antenna or a circularly polarized wave, a phaser is not required. Further, in the microwave radiation portion 43, the slow wave member 82 is not necessary.

Further, in the above-described embodiment, an example in which a plurality of microwave radiation portions are provided, and a plurality of microwave radiation antennas are provided, but only one of a microwave radiation portion and a microwave radiation antenna may be used.

In the above embodiment, the etching treatment apparatus is exemplified as the plasma processing apparatus. However, the present invention is not limited thereto, and may be used for oxynitride treatment, ashing treatment, etc. including film formation treatment, oxidation treatment, and nitridation treatment. Other plasma treatments. Further, the substrate to be processed is not limited to the semiconductor wafer W, and may be an FPD (flat display) substrate represented by a substrate for an LCD (liquid crystal display) or another substrate such as a ceramic substrate.

111‧‧‧ gas piping

121‧‧‧Antenna body

121a‧‧‧ upper wall

121b‧‧‧ sidewall

121c‧‧‧ bottom wall

122‧‧‧Slots

122A‧‧‧Upper

122B‧‧‧ lower

123‧‧‧ gas diffusion space

124‧‧‧ gas inlet

125‧‧‧ gas ejection holes

126‧‧‧ dielectric layer

127‧‧ ‧ district

43‧‧‧Microwave Radiation Department

44‧‧‧Microwave transmission path

45‧‧‧Antenna

52‧‧‧Outer conductor

53‧‧‧Inside conductor

54‧‧‧Power supply agency

55‧‧‧Microwave electric power introduction埠

56‧‧‧Coaxial line

56a‧‧‧Inside conductor

56b‧‧‧Outer conductor

58‧‧‧reflector

59‧‧‧Slow wave material

60‧‧‧ Tuner

61a, 61b‧‧‧ slag

63‧‧‧Sliding material

64a, 64b‧‧‧Slag moving axis

67‧‧‧floor

68‧‧‧Slag controller

70‧‧‧Slag Drive Department

71‧‧‧ frame

72a, 72b‧‧‧ gears

73a, 73b‧‧‧ motor

74a, 74b‧‧‧ gears

75a, 75b‧‧‧ encoder

82‧‧‧ Slow wave material

82a‧‧‧Cylindrical components

90‧‧‧Power antenna

91‧‧‧Antenna body

92‧‧‧1st pole

93‧‧‧2nd pole

94‧‧‧Reflection Department

Claims (12)

A microwave radiation antenna is a microwave radiation antenna that radiates microwaves that are output from a microwave output unit and is transmitted to a microwave transmission path into a chamber, in a plasma processing apparatus that forms surface wave plasma in a chamber and performs plasma processing. An antenna body composed of a conductor; a plurality of slots provided in the antenna body to radiate microwaves; and a plurality of gas ejection holes provided in the antenna body to discharge the processing gas into the chamber; and A metal surface wave is formed on the surface, whereby surface wave plasma is generated by the metal surface wave; and at least a portion of the metal surface of the antenna body is electrically insulated from the surface wave plasma by DC. The microwave radiation antenna of claim 1, wherein at least a portion of the surface of the antenna body is insulated by covering with a dielectric layer capable of maintaining a thickness of the surface wave of the metal. The microwave radiation antenna of claim 2, wherein the thickness of the dielectric layer is λ/7 or less when the microwave wavelength in the vacuum is λ. The microwave radiation antenna of claim 2, wherein the dielectric layer is a film formed by a film formation technique. The microwave radiation antenna of claim 2, wherein the dielectric layer is formed by a dielectric thin plate. The microwave radiation antenna of claim 5, wherein the dielectric thin plate has a metal film having a pattern in which the groove and the gas ejection hole are removed in a portion opposite to the antenna body. The microwave radiation antenna of claim 6, wherein the plurality of slots are circumferentially disposed on a surface of the antenna body, and the metal film is disposed on the dielectric thin plate. The center corresponds to the position range of the outer diameter of the slot. The microwave radiation antenna of claim 1, wherein the antenna system is insulated from the chamber by DC. A microwave plasma source is a microwave plasma source that radiates microwaves into a chamber of a plasma processing apparatus to form a surface wave plasma, and has a microwave output portion that generates microwaves and outputs; and is used for outputting from the microwaves The microwave outputted from the unit is supplied to the microwave supply unit in the chamber; the microwave supply unit includes a transmission path for transmitting the microwave output from the microwave output unit, and a microwave radiation antenna for radiating the microwave into the chamber; The microwave radiation antenna includes: an antenna body composed of a conductor; a plurality of slots provided in the antenna body to radiate microwaves; and a plurality of gas ejection holes provided in the antenna body to discharge the processing gas into the chamber; The surface wave is formed on the surface by the microwave, and the surface wave plasma is generated by the surface wave of the metal, and at least a part of the metal surface of the antenna body is electrically insulated from the surface wave plasma by DC. The microwave plasma source of claim 9, wherein the microwave supply unit has a plurality of microwave radiation antennas. A plasma processing apparatus comprising: a chamber for accommodating a substrate to be processed; a gas supply mechanism for supplying a processing gas; and a microwave plasma source for radiating microwaves into the chamber to form surface wave plasma; the microwave plasma The source system has: a microwave output unit that generates microwaves and outputs a microwave supply unit for supplying microwaves output from the microwave output unit to the chamber; the microwave supply unit includes microwaves to be output from the microwave output unit a transmission path for transmitting; and a microwave radiation antenna for radiating microwaves into the chamber; the microwave radiation antenna having: an antenna body formed of a conductor; a plurality of slots provided in the antenna body to radiate microwaves; and Disposing a processing gas to the plurality of gas ejection holes in the chamber; and forming a metal surface wave on the surface by the microwave, thereby generating a surface wave plasma by the metal surface wave, and at least a metal surface of the antenna body a part of the surface wave plasma is electrically insulated from the surface; the metal surface wave formed on the surface of the microwave radiation antenna by microwaves supplied from the microwave plasma source into the chamber generates The surface wave plasma of the gas supplied by the gas supply mechanism is treated by plasma to treat the substrate to be processed in the chamber. The plasma processing apparatus of claim 11, wherein the microwave supply unit has a plurality of the microwave radiation antennas.