JP2000174003A - Device and method for processing micro wave exciting plasma - Google Patents

Abstract

PROBLEM TO BE SOLVED: To be able to suppress products from peeling. SOLUTION: This device 20 is so constituted of a ceiling board 30 which is provided at a terminal side of a guide wave tube and to which micro wave is propagated, as the micro wave to radiate from a micro wave introducing port formed on the ceiling board 30 toward the inside of a responding vessel 21 and as medium gas to turn to plastic radiation for a board 22 to be processed to plasmic radiation. In this case the device is provided with a dielectric window 37 which encloses an upper terminal port of the responding vessel 21 in airtight, transmits the micro wave and guides a processed of the micro wave at the inside, and with a dielectric member 33 which is provided corresponding to a slot antenna 32 at the spot closer to the ceiling board side 30 than the dielectric window 37, introduces the micro wave radiated by the slot antenna 32, and regulates the processed to the H surface direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a microwave-excited plasma processing apparatus and a plasma processing method used for etching and ashing in the production of semiconductors and liquid crystals.

[0002]

2. Description of the Related Art As a conventional microwave-excited plasma processing apparatus, one having a structure shown in FIGS. 11A and 11B is known. The microwave-excited plasma processing apparatus 1 includes:
A reaction vessel 2 is provided. The top plate 3 is attached to the upper end of the reaction vessel 2, and a rectangular waveguide 4
Are attached to form a microwave introduction part.
The top plate 3 is formed with a slit-shaped slot antenna 5 as a microwave introduction port for introducing microwaves downward.

[0003] Below the top plate 3, a dielectric window 6 is attached to the top plate 3 so as to hermetically close the reaction vessel 2 via a sealing member such as an O-ring 7. .

The reaction vessel 2 is vertically divided by a diffusion plate 8 into, for example, a cylindrical plasma generation chamber 9 and a processing chamber 10. A gas supply pipe 11 is connected to a side wall of the plasma generation chamber 9 to supply a processing gas such as oxygen to the inside.

[0005] Inside the processing chamber 10, there is provided a wafer holder 14 on which a rotating shaft 12 is mounted on a lower surface and on which a wafer 13 as a substrate to be processed is placed at a predetermined distance from the diffusion plate 8. .

An exhaust pipe 15 for vacuum suction of the inside of the reaction vessel 2 is formed on the bottom surface of the processing chamber 10 and connected to a suction pump provided outside, and the pressure inside the reaction vessel 2 is reduced to a low pressure. The suction operation is performed so that

In the microwave-excited plasma processing apparatus 1 having such a configuration, the processing gas is supplied into the plasma generation chamber 9 through the gas supply pipe 11 after the internal pressure is reduced to a low pressure by vacuum suction. After supplying the processing gas, a microwave is introduced into the inside through the waveguide 4, the top plate 3, and the dielectric window 6, and the processing gas is turned into plasma.

The processing gas converted into plasma passes through the diffusion plate 8 and is uniformly dispersed and introduced into the processing chamber 10 to plasma-process the wafer 13 on the wafer holder 14.

[0009]

When microwaves are radiated from the slot antenna 5 into the plasma generation chamber 9, the microwaves have a distribution shown in FIG. The microwave propagates through the dielectric window 6 and is absorbed by the plasma in the plasma generation chamber 9. Here, when the pressure inside the plasma generation chamber 9 is high (about 100 Pa), the microwaves are absorbed so much that the microwaves are attenuated and hardly propagated to the periphery of the dielectric window 6.

Conversely, when the pressure inside the plasma generation chamber 9 is low (20 Pa), the absorption of the microwave into the plasma is reduced, and the attenuation of the microwave is suppressed.
The plasma spreads throughout the dielectric window 6. In this case, the side wall inside the plasma generation chamber 9 is etched (sputtered, etc.) by the spread plasma, and when the inner wall inside the plasma generation chamber 9 is made of aluminum, the aluminum is scattered and dust is generated. generate.

Here, when a fluorine-based gas is used as the etching gas, the scattered aluminum and fluorine combine to generate dust of aluminum fluoride (AlF).

When dust of aluminum fluoride is generated, the dust adheres again to the plasma generation chamber 9 and forms a film. When the aluminum fluoride dust accumulates to a predetermined thickness, the aluminum fluoride dust may be peeled off to produce a peeled product. When a peeled object is generated, the wafer 1 which is a non-processing object
3 may fall as particles on the upper surface.

If the above-mentioned particles adhere to the upper surface of the wafer 13, the processing of the wafer 13 is affected.
There is a demand for a microwave-excited plasma processing apparatus having a configuration that minimizes the configuration of dust.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a plasma processing apparatus and a plasma processing apparatus capable of suppressing generation of a separated material.

[0015]

According to a first aspect of the present invention, a microwave is propagated by a waveguide to a microwave inlet, and the microwave is introduced from the microwave inlet through a dielectric window. In a microwave-excited plasma processing apparatus that introduces microwaves into a reaction vessel and converts the medium gas supplied into the reaction vessel into a plasma to plasma-treat a substrate to be processed, the microwaves propagating in the dielectric window are A microwave-excited plasma processing apparatus comprising a propagation direction control means for controlling a propagation direction.

According to a second aspect of the present invention, the propagation direction control means is provided between the microwave introduction port and the dielectric window, and is provided with a plate member having a hole corresponding to the microwave introduction port. 2. The microwave-excited plasma processing apparatus according to claim 1, further comprising a dielectric member fitted into said hole.

According to a third aspect of the present invention, there is provided the microwave-excited plasma processing apparatus according to the second aspect, wherein the dielectric members are provided separately according to the number of the microwave introduction ports. .

According to a fourth aspect of the present invention, the dielectric member includes:
3. The microwave-excited plasma processing apparatus according to claim 2, wherein the microwave-excited plasma processing apparatus is formed of a single member capable of covering all the microwave introduction ports.

According to a fifth aspect of the present invention, the microwave introduction port is formed on a top plate provided between the waveguide and the dielectric window, and the propagation direction control means includes: 2. The microwave-excited plasma processing apparatus according to claim 1, wherein a groove is formed on a surface of the plate on an outer peripheral side of the microwave introduction port and on a surface facing the dielectric window.

According to a sixth aspect of the present invention, the microwave introduction port is formed on a top plate provided between the waveguide and the dielectric window, and the propagation direction control means is provided on the top plate. A convex portion formed on the outer peripheral side of the microwave introduction port of the plate and facing the dielectric window, and a concave portion formed on the dielectric window so as to be fittable with the convex portion. The microwave-excited plasma processing apparatus according to claim 1, comprising:

According to a seventh aspect of the present invention, the microwave introduction port is formed on a top plate provided between the waveguide and the dielectric window, and the propagation direction control means is provided on the top plate. 2. The microwave-excited plasma processing apparatus according to claim 1, comprising a through-hole formed in the plate, and a rod-shaped member provided so that the insertion depth can be freely adjusted in the through-hole.

According to a ninth aspect of the present invention, the microwave introduction port is formed in a top plate provided between the waveguide and the dielectric window, and the propagation direction control means includes A through-hole formed in the plate, a hole formed at the position of the dielectric window corresponding to the through-hole, inserted into the through-hole and the hole, and provided so that the insertion depth can be freely adjusted. The microwave-excited plasma processing apparatus according to claim 1, wherein the apparatus is formed of a rod-shaped member.

As a result of taking the above measures, the following operation occurs. According to the first aspect of the present invention, since the propagation direction control means is provided, the traveling of the microwave in the dielectric window can be controlled in a predetermined direction. Therefore, if the microwaves reaching the inner wall of the reaction vessel are controlled, the microwaves reaching here are reduced. Thereby, it is possible to reduce the generation of dust due to the reaction of the inner wall by the microwave.

According to the second aspect of the present invention, since the dielectric member is fitted and attached to the hole of the plate member, the microwave member is disposed between the top plate and the dielectric window. Of the dielectric window in a predetermined direction, such as the width direction, can be controlled.

According to the third aspect of the present invention, since the dielectric members are separately provided in accordance with the number of the microwave introduction ports, it is sufficient to use only a necessary amount as the dielectric member, and the amount of material used is reduced. can do.

According to the fourth aspect of the present invention, since the dielectric member is formed of a single member that covers all the microwave introduction ports, the number of locations for attaching the dielectric member is small, and the installation is not troublesome.

According to the fifth aspect of the present invention, since the propagation direction control means is the groove formed on the outer peripheral side of the microwave introduction port of the top plate and on the surface facing the dielectric window, the microwave enters the groove. Can be reflected. Therefore, it is possible to reduce the propagation of the microwave in the direction along the width direction of the dielectric window.

According to the sixth aspect of the present invention, the convex portion and the concave portion fitted to the convex portion reflect microwaves along the width direction of the dielectric window, and reflect the microwave in the width direction of the dielectric window. The traveling microwave can be reduced.

According to the seventh aspect of the present invention, since the propagation direction control means is constituted by the through hole formed in the top plate and the rod-shaped member provided in this through hole so that the insertion depth can be freely adjusted, the through hole is provided. If you adjust the insertion depth of the rod-shaped member with respect to
The degree of microwave reflection can be adjusted.

Further, since the degree of reflection of microwaves can be freely adjusted, the degree of reflection of microwaves can be freely adjusted according to the insertion depth of the rod-shaped member.

According to the eighth aspect of the present invention, since the rod-shaped member can be inserted also into the hole formed in the dielectric window, the reflection of the microwave can be further improved by adjusting the insertion depth of the rod-shaped member. It becomes possible.

According to the ninth aspect of the present invention, by controlling the direction of propagation of microwaves, for example, the amount of microwaves reaching the inner wall of the reaction vessel can be reduced. For this reason, dust generated from the inner wall by the microwave can be reduced, and the plasma processing of the substrate to be processed can be favorably performed.

[0033]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) An embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 shows a microwave-excited plasma processing apparatus 2
FIG. 2 is a front cross-sectional view showing the configuration of FIG. 0. The microwave-excited plasma processing apparatus 20 shown in this figure enters a microwave into a reaction vessel 21 and utilizes the incident microwave to produce a reaction vessel. The processing is performed on a substrate to be processed 22 such as a liquid crystal substrate or a semiconductor wafer provided in the inside 21.

The reaction vessel 21 is made of aluminum. Inside the reaction vessel 21, a diffusion plate 25 is provided which divides the upper side into a plasma generation chamber 23 and the lower side into a processing chamber 24. ing. A medium gas is supplied to the plasma generation chamber 23 by a medium gas supply pipe 27 described later, and thereafter, the microwave is introduced to convert the medium gas into plasma. This diffusion plate 25
The diffusion plate 25 is used to make the concentration of the reaction gas in the processing chamber 24 appropriately uniform.

The plasma homogenized by the diffusion plate 25 travels toward the substrate 22 provided in the processing chamber 24, and plasma processing such as etching and ashing is performed on the surface of the substrate 22.

An exhaust pipe 26, the other end of which is connected to a vacuum pump (not shown), is connected to the bottom inside the processing chamber 24, and the inside of the reaction vessel 21 is evacuated to a high vacuum. The other end of the medium gas supply pipe 27 whose one end is connected to a medium gas supply source (not shown) is connected to the side wall of the plasma generation chamber 23. After the inside of the reaction vessel 21 is made high vacuum by the exhaust pipe 26, a medium gas such as a mixed gas of oxygen and a fluorine-based gas is supplied from the medium gas supply pipe 27 to the reaction vessel 2.
1 inside.

In the processing chamber 24, the substrate 22 to be processed is provided.
Is mounted on the wafer holder 28. A rotating shaft 29 is connected below the wafer holder 28, and the rotating shaft 29 projects from the bottom of the processing chamber 24 and is connected to a driving source (not shown). Therefore, a rotational driving force is transmitted to the wafer holder 28 from a driving source (not shown).

The wafer holder 28 is provided with a not-shown RF bias and He cooling mechanism, and is also connected to a not-shown RF oscillator and a chiller.

A dielectric window 37 is provided above the plasma generation chamber 23. The dielectric window 37 is made of a material such as SiO ₂ , Al ₂ O ₃ , AlN, or a fluororesin, and allows microwaves to propagate. The dielectric window 37 is connected to the plasma generation chamber 2.
3 is formed in a large area so as to cover the whole upper surface opening, and closes the plasma generation chamber 23. That is,
A step-shaped engaging portion 38 is formed on the upper end opening side of the plasma generation chamber 23, and the dielectric window 37 is locked to the engaging portion 38.

When the dielectric window 37 is locked to the engaging portion 38, the dielectric window 37 is locked to the engaging portion 38 via an O-ring (not shown) to hermetically close the inside of the reaction vessel 21. .

A top plate 30 made of a metal plate is provided above the dielectric window 37, and a rectangular waveguide 31 into which microwaves are introduced is provided above the top plate 30. It is provided so as to cover a part of the top plate 30. One end of the waveguide 31 is connected to an oscillator (not shown) via a matching device, and the microwave generated by the oscillator is introduced into the top plate 30 by the waveguide 31. I have. The waveguide 31 is made of a metal plate, and has a reflection surface 31a on the other end side for reflecting an incident microwave.

A slit-shaped slot antenna 32 serving as a microwave introduction port is formed on the top plate 30 along the longitudinal direction of the waveguide 31. The slot antenna 32 has a hole shape penetrating the top plate 30, and guides the microwaves that travel inside the waveguide 31 and reach the top plate 30 into the plasma generation chamber 23. The slot antenna 32 has a predetermined width as shown in FIG. 1, and formed one by one on both sides on the central axis O ₁ along the longitudinal direction a center in the width direction of the waveguide 31 as a symmetrical ing. Further, in the present embodiment, the slot antenna 32 is formed such that the reflection surface 31a side is formed to be narrow, and the entrance side becomes wide from a position facing the microwave incidence side from the reflection surface 31a by a predetermined distance. It is formed in a suitable shape.

However, the shape of the slot antenna 32 is not limited to this, and the shape and the number may be variously changed.

The dielectric window 3 is provided below the top plate 30.
Propagation direction control means for controlling the propagation direction of the microwave in 6 is provided. This propagation direction control means changes the shape of the slot antenna 32 so that the microwave passing through the slot antenna 32 can be introduced.
And a support plate 35 having a hole 36 which is a through hole whose width is regulated within a predetermined range in order to control the propagation direction of the microwave, and fitted into the hole 36. For example, SiO ₂ , Al ₂ O ₃ , AlN,
The dielectric member 33 is made of a dielectric material such as fluororesin.

The operation of the microwave-excited plasma processing apparatus 20 having the above configuration will be described below.

After vacuuming the inside of the reaction vessel 21, a medium gas is supplied into the plasma generation chamber 23 so as to have a predetermined pressure. Then, after this supply, the microwave is generated from the oscillator and transmitted inside the waveguide 31, and the microwave is transmitted from the slot antenna 32 to the plasma generation chamber 2.
3 Introduce inside.

The microwave introduced toward the plasma generation chamber 23 is introduced into the dielectric member 33. Dielectric member 33
Is provided such that its width becomes a predetermined width. When microwaves are emitted from the dielectric member 33, the emission direction is restricted. Specifically, as shown in FIG. 3, in the range of 0 to 35 degrees and the range of 145 to 180 degrees, which are angles nearly parallel to the dielectric window 37, microwave radiation is almost blocked. I have.

However, when microwaves are radiated from the dielectric member 33 to the dielectric window 37, the microwaves slightly travel inside the dielectric window 37 in a direction parallel to the dielectric window 37 due to microwave diffraction and the like. However, the intensity of the microwave traveling in a direction parallel to the dielectric window 37 is reduced.

As described above, the microwave traveling in the direction parallel to the dielectric window 37 is reduced and the plasma
Microwaves are emitted inside 3. When the microwave is emitted, the medium gas inside the plasma generation chamber 23 is turned into plasma.

The plasma generated inside the plasma generation chamber 23 is introduced into the processing chamber 24 after passing through the diffusion plate 25. Then, the plasma advances to the substrate to be processed 22 placed on the wafer holder 28, and the plasma processing of the substrate to be processed 22 is performed.

In this case, an RF oscillator and a chiller (not shown) are also operated so that the substrate 22 to be processed is satisfactorily processed.

The plasma processing is performed as described above.

According to the microwave-excited plasma processing apparatus 20 having such a configuration, the dielectric member 33 is provided, and the propagation direction of the microwave in the dielectric window 37 is restricted by the dielectric member 33. The state in which the microwaves reaching the inner wall surface of 21 are reduced. Therefore, it is possible to reduce the generation of dust made of aluminum as a result of the microwave reacting with the inner wall surface of the reaction vessel 21. Therefore, it is possible to reduce the generation of aluminum fluoride (AlF) dust by combining aluminum dust with the fluorine-based gas.

Therefore, it is possible to minimize the amount of aluminum fluoride dust re-adhering to the inner wall surface of the plasma generation chamber 23.

Further, the propagation of the microwave to the inner wall surface of the plasma generation chamber 23 is reduced, and the inner wall surface of the plasma generation chamber 23 is prevented from being etched. It also contributes to longer life.

Although the first embodiment of the present invention has been described above, the present invention can be variously modified. Hereinafter, this will be described.

In the above embodiment, the elongated hole 36 is formed in the support plate 35, and the dielectric member 33 corresponding to the elongated hole 36 is inserted and attached. The shape of the hole 33 and the hole 36 is not limited to this. For example, as shown in FIG. 4, a dielectric member 39 made of a single large-area member covering both the two slot antennas 32 is provided on a support plate 35. No problem. In this case, there are few places to attach the dielectric member 39, and it is not necessary to take time to attach the dielectric member 39.

The shape, number, and position of the slot antennas 32 can be variously modified.

Further, in the above embodiment, the waveguide 31
Is set so that the H plane (the plane perpendicular to the direction of the microwave electric field) is parallel to the dielectric window 37 and the E plane (the plane parallel to the direction of the microwave electric field) is perpendicular to the dielectric window 37. Although provided, the surface E may be provided so as to be parallel to the dielectric window 37. In this case, as shown in FIG.
In comparison with the structure, the waveguide 31 is provided vertically with respect to the top plate 30. In this case, the direction of the E-plane is different from that of the microwave-excited plasma processing apparatus 20 shown in FIGS. 1 and 2 and is parallel to the top plate 30. Can be performed.

When a plurality of slot antennas 32 are provided, a plurality of waveguides 31 may be provided, and a suitable number of slot antennas 32 may be covered with the waveguides 31. That is, even when a plurality of waveguides 31 are provided, each of the waveguides 31 may have one or a plurality of slot antennas 32.

Further, in the above embodiment, the reaction vessel 2
Although the material 1 is described as aluminum, the material of the reaction vessel 21 may be other than aluminum, such as iron, or the material of the inner wall may be aluminum.

(Second Embodiment) Hereinafter, a second embodiment of the present invention will be described with reference to FIGS.

The configuration of the microwave-excited plasma processing apparatus 40 of the present embodiment is basically the same as the configuration described in the first embodiment. That is, the microwave-excited plasma processing apparatus 40 also has the plasma generation chamber 2 on the upper side.
3. The lower side has a reaction vessel 21 divided into a processing chamber 24, and a diffusion plate 25 for dividing the reaction vessel 21 is provided.

A wafer holder 28 on which the substrate to be processed 22 is placed is provided inside the processing chamber 24, and a rotating shaft 29 is connected to the wafer holder 28. A medium gas supply pipe 27 (not shown in FIG. 6) for introducing a medium gas into the plasma generation chamber 23 is provided. Exhaust pipe 26 is provided.

The reaction vessel 21 is provided at the leading end of the waveguide 31 for propagating the microwave generated by the oscillator.
A top plate 41 for closing the inside is provided. The top plate 41 has a slot antenna 4 as in the first embodiment.
2 are formed, and microwaves can be emitted toward the inside of the reaction vessel 21 via the slot antenna 42. The microwave radiated from the slot antenna 42 is introduced into a dielectric window 37 provided to face and close to the top plate 41.

Here, on the outer side of the slot antenna 42 of the top plate 41, a groove 43 as a propagation direction control means is formed. The groove 43 is provided on the top plate 41.
And is formed in a long groove parallel to the slot antenna 42 and substantially corresponding to the length of the slot antenna 42.

The groove 43 is formed at a predetermined depth where microwaves can enter.
In order to prevent leakage of microwaves to the outside, it is formed so as not to penetrate the top plate 41.

In the present embodiment, three grooves 43 are formed on each side, and the three grooves 43 can reduce the progress of the microwave in the width direction in a stepwise manner. . However, when microwaves can be reduced by one groove 43, only one groove 43 may be formed, or a predetermined number of grooves may be formed.

According to the configuration of the microwave-excited plasma processing apparatus 40 having the above configuration, the microwave radiated from the slot antenna 42 to the dielectric window 37 will travel in a direction parallel to the dielectric window 37. However, since the groove 43 is formed in the middle of the microwave traveling path, the microwave enters the groove 43 and the groove 4
3 is reflected by the inner wall surface.

That is, since the microwaves that have entered the groove 43 are reflected by the inner wall surface of the groove 43, the microwaves that propagate to the inner wall surface of the plasma generation chamber 23 are reduced.

Therefore, only by forming the groove 43 in the top plate 41, the microwave is reflected and the plasma generation chamber 2
3, because the propagation of microwaves to the inner wall side can be reduced,
Although the configuration is simple, it is possible to achieve the same effects as those described in the first embodiment. That is, the propagation of the microwave in the direction parallel to the dielectric window 37 can be reduced, so that the inner wall surface of the plasma generation chamber 23 is etched to generate dust made of aluminum, and this aluminum is bonded to the fluorine-based gas. Thus, the generation of aluminum fluoride (AlF) dust can be reduced.

Therefore, the aluminum fluoride dust adheres again to the inner wall surface of the plasma generation chamber 23, and the amount of the film formed on the inner wall surface can be reduced. Can be minimized.

Further, since the propagation direction control means is formed only by forming the groove portion 43 on the top plate 41, the manufacture is easy, and the cost required for this is reduced because no separate dielectric member is provided. .

When the grooves 43 are formed, the microwave reflection state can be appropriately adjusted according to the number of grooves 43 formed, the interval, and the depth. For this reason, the degree of freedom of adjustment at the time of manufacture is increasing.

Although the second embodiment of the present invention has been described above, the present invention can be variously modified. This is described below.

In the above embodiment, the top plate 41 has the groove 43
The microwave is reflected by the groove 43. As shown in FIG. 9, the dielectric window 37 of the top plate 41 is formed.
A protruding portion 44 is formed by projecting a portion facing
A concave portion 45 that can be fitted with the convex portion 44 may be formed in the dielectric window 37. In this case, the reflection of the microwave is favorably performed by the convex portion 44 fitted to the dielectric window 37, and the same operation and effect as in the above-described case can be obtained.

The groove 43 does not necessarily have to be formed in a long groove shape, and the shape and arrangement thereof can be variously modified as long as microwaves can be reflected well.

(Third Embodiment) Hereinafter, a third embodiment of the present invention will be described with reference to FIG.

The microwave-excited plasma processing apparatus 50 of this embodiment has basically the same configuration as that described in the above-described first and second embodiments. That is, the microwave-excited plasma processing apparatus 50 also includes the plasma generation chamber 23, the processing chamber 24, the diffusion plate 25, and the exhaust pipe 2
6, a medium gas supply conduit 27, a wafer holder 28, a rotating shaft 29, a top plate 30, a waveguide 31, and a slot antenna 32. In addition, a dielectric window 37 is arranged to face the top plate 30.

A through hole 51 is formed in the top plate 30 at a position outside the waveguide 31. Also, the dielectric window 3
A hole 52 having an appropriate depth is formed at a position corresponding to the through hole 51 of FIG. The width and length of the hole 52 are
The through holes 51 are formed in the same manner. In the present embodiment, the through-hole 51 and the hole 52 are formed in a long hole shape as in the case of the slot antenna 32, and are substantially parallel to the through-hole 51 and the hole 52. Is formed.

A microwave shielding bar 53 is provided so as to be inserted into both the through hole 51 and the hole 52.
The microwave shielding bar 53 is provided so as to be freely inserted into the top plate 30 and the hole 52 from the outside of the top plate 30. The microwave shielding bar 53 is formed of an aluminum metal bar, and is made of a material that enables control of the propagation direction of the microwave in the dielectric window 37. The microwave shielding bar 53 is also formed in a long plate-like member so that the microwave shielding bar 53 can be fitted into the long hole shape of the through hole 51 and the hole 52.

In the present embodiment, three sets of the through-hole 51, the hole 52, and the microwave shielding rod 53 are provided, and the configuration is such that the microwave is reduced stepwise. In addition,
As long as the microwave can be effectively reduced, only one set of the through-hole 51, the hole 52, and the microwave shielding rod 53 may be provided, or any number of the through-holes and the microwave shielding rod 53 may be provided.

According to the configuration of the microwave-excited plasma processing apparatus 50 having the above-described configuration, the microwave radiated from the slot antenna 32 to the dielectric window 37 propagates in a direction parallel to the dielectric window 37. However, a through hole 51, a hole 52, and a microwave shielding bar 53 are provided in the middle of the microwave traveling path, and if the insertion depth of the microwave shielding bar 53 is adjusted and inserted, The propagation of the microwave is blocked and reflected by the microwave shielding bar 53.

For this reason, the microwave plasma generation chamber 2
3 can be reduced to be transmitted to the side wall, and the generation of aluminum dust can be suppressed.

Further, if the insertion depth of the microwave shielding bar 53 is adjusted, it is possible to appropriately adjust the degree of microwave reflection.

Although the third embodiment of the present invention has been described above, the present invention can be variously modified. Hereinafter, this will be described.

In the above embodiment, the through holes 51 and the holes 52 are formed in both the top plate 30 and the dielectric window 37, respectively. A configuration in which the hole 52 is not formed in the window 37 may be adopted. In this case, the insertion depth of the microwave shielding rod 53 is adjusted to form the groove as described in the second embodiment in the top plate 30 so that the microwave can be reflected. be able to.

The arrangement, shape, and the like of the through-hole 51, the hole 52, and the microwave shielding bar 53 can be appropriately modified.

The first to third embodiments of the present invention have been described above. However, the present invention can be variously modified without departing from the scope of the present invention.

[0091]

As described above, according to the present invention,
Since the propagation direction of the microwave can be regulated by the microwave traveling regulation means, the microwave reaching the inner wall of the reaction vessel can be reduced, and the generation of dust can be reduced.

[Brief description of the drawings]

FIG. 1 is a front sectional view showing a configuration of a microwave-excited plasma processing apparatus according to an embodiment of the present invention.

FIG. 2 is a side sectional view showing the configuration of the microwave-excited plasma processing apparatus according to the embodiment;

FIG. 3 is a diagram showing a state of emission of microwaves according to the embodiment;

FIG. 4 is a front cross-sectional view showing a configuration of a microwave-excited plasma processing apparatus according to a modification of the embodiment.

FIG. 5 is a front sectional view showing the configuration of a microwave-excited plasma processing apparatus according to a modification of the embodiment.

FIG. 6 is a front sectional view showing a configuration of a microwave-excited plasma processing apparatus according to a second embodiment of the present invention.

FIG. 7 is a plan view showing the shape of the top plate according to the embodiment.

FIG. 8 is a partially enlarged view of a top plate and a dielectric window according to the embodiment.

FIG. 9 is a partially enlarged view of a top plate and a dielectric window according to a modification of the embodiment.

FIG. 10 is a partial cross-sectional view illustrating a configuration of a microwave-excited plasma processing apparatus according to a third embodiment of the present invention.

11A and 11B are diagrams showing a configuration of a conventional microwave-excited plasma processing apparatus, wherein FIG. 11A is a front sectional view, and FIG. 11B is a front sectional view of a waveguide, a top plate, a dielectric window, and a plasma generation chamber. Is shown.

FIG. 12 is a diagram showing a conventional microwave emission state.

[Explanation of symbols]

20, 40, 50, 60 ... microwave excitation plasma processing apparatus 21 ... reaction vessel 22 ... substrate to be processed 23 ... plasma generation chamber 24 ... processing chamber 30 ... top plate 31 ... waveguide 32 ... slot antenna 33 ... dielectric member 35 ... Support plate 37 ... Dielectric window 43 ... Groove 51 ... Through hole 52 ... Hole 53 ... Microwave shielding rod 61 ... Matching device

Continued on the front page F term (reference) 5F004 AA16 BA16 BB11 BB18 BB28 BC08 DA01 DA02 DA03 DA15 DA16 DA17 DA18 DA19 DA20 DB00 DB09 DB16

Claims (9)

[Claims] 1. A microwave propagates through a waveguide to a microwave inlet, a microwave is introduced into the reaction vessel from the microwave inlet through a dielectric window, and a medium gas supplied into the reaction vessel is provided. A microwave-excited plasma processing apparatus for plasma-treating a substrate to be processed by converting it into plasma, comprising a propagation direction control means for controlling a propagation direction of the microwave propagating in the dielectric window. Plasma processing equipment. 2. A plate member provided between the microwave introduction port and the dielectric window and having a hole corresponding to the microwave introduction port, the propagation direction control means being fitted between the microwave introduction port and the dielectric window. 2. The microwave-excited plasma processing apparatus according to claim 1, wherein the apparatus is constituted by a combined dielectric member. 3. The microwave-excited plasma processing apparatus according to claim 2, wherein said dielectric members are provided separately according to the number of said microwave introduction ports. 4. The microwave-excited plasma processing apparatus according to claim 2, wherein the dielectric member is formed of a single member capable of covering all the microwave introduction ports. 5. The microwave introduction port is formed in a top plate provided between the waveguide and the dielectric window, and the propagation direction control means is configured to control the microwave introduction port of the top plate. 2. The microwave-excited plasma processing apparatus according to claim 1, wherein the groove is formed on the outer peripheral side of the substrate and on a surface facing the dielectric window. 6. The microwave introduction port is formed in a top plate provided between the waveguide and the dielectric window, and the propagation direction control means is configured to control the microwave introduction port of the top plate. A convex portion protrudingly formed on the outer peripheral side of the surface facing the dielectric window, and a concave portion formed on the dielectric window so as to be fittable with the convex portion. The microwave-excited plasma processing apparatus according to claim 1. 7. The microwave introduction port is formed in a top plate provided between the waveguide and the dielectric window, and the propagation direction control means includes a through-hole formed in the top plate. 2. The microwave-excited plasma processing apparatus according to claim 1, comprising a hole, and a rod-shaped member provided in the through-hole so that the insertion depth can be freely adjusted. 8. The microwave introduction port is formed in a top plate provided between the waveguide and the dielectric window, and the propagation direction control means includes a through-hole formed in the top plate. A hole, a hole formed at the position of the dielectric window corresponding to the through-hole, and a rod-shaped member inserted into the through-hole and the hole, and provided so that the insertion depth can be freely adjusted. The microwave-excited plasma processing apparatus according to claim 1, wherein: 9. A step of sucking a gas inside the reaction vessel to lower the inside of the reaction vessel to a predetermined pressure; a step of introducing a processing gas into the inside of the reaction vessel to bring the inside of the reaction vessel to a predetermined pressure; A step of propagating microwaves oscillated from an oscillator to a microwave inlet through a waveguide; and a dielectric disposed in an opening formed in the reaction vessel for the microwaves transmitted through the microwave inlet. While controlling the propagation direction in the window, it is introduced into the reaction vessel,
A step of generating plasma by reacting with the processing gas; a step of processing a substrate to be processed disposed in the reaction vessel with the generated plasma; and a step of exhausting a gas obtained by processing the substrate to be processed. A plasma processing method comprising: