JPH11329792A - Microwave supply container - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide uniform microwave radiation intensity distribution by concentrically arranging a plurality of circular wave guide paths having a plane-shaped H surface having a plurality of slots separately installed each other and a rectangular cross section vertical to the advancing direction of a microwave so that the H surface becomes the same plane. SOLUTION: This microwave supply container 3 has a circular wave guide 3a having an H surface on which a plurality of slots are separately installed and a rectangular cross section vertical to the advancing direction (direction vertical to space) of a microwave. Microwaves introduced from a microwave guide inlet 13 into the microwave supply container 3 change courses in the opposite directions each other with a distributor 10 such as an E branch block, and are propagated into a circular wave guide path 3a. Active species of gas or gas ions are sufficiently supplied also to the vicinity of the center O of a space 9 where the slots 3b do not exist. Uniform plasma treatment is conducted over the whole treating surface of a treated object W.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a microwave feeder having multiple annular waveguides.

[0002]

2. Description of the Related Art As a plasma processing apparatus using a microwave as an excitation source for generating plasma, a plasma polymerization apparatus, a CVD apparatus, a surface reforming apparatus, an etching apparatus, an ashing apparatus, a cleaning apparatus and the like are known.

[0003] CVD using such a so-called microwave plasma processing apparatus is performed, for example, as follows. That is, a gas is introduced into a plasma generation chamber and / or a film formation chamber of a microwave plasma CVD apparatus, and at the same time, microwave energy is applied to generate plasma in the plasma generation chamber to excite and / or decompose the gas to generate plasma. A deposited film is formed over an object to be processed provided in a chamber or a deposition chamber. And the plasma polymerization of organic matter, acid value, nitriding,
Surface modification such as fluorination can also be performed.

[0004] Etching of an object to be processed using a so-called microwave plasma etching apparatus is performed, for example, as follows. That is, an etchant gas is introduced into the processing chamber of the apparatus, and simultaneously, microwave energy is applied to excite and / or decompose the etchant gas to generate plasma in the processing chamber. The surface of the processed object is etched.

[0005] Further, ashing processing of an object to be processed using a so-called microwave plasma ashing apparatus is performed, for example, as follows. That is, an ashing gas is introduced into the processing chamber of the apparatus, and at the same time, microwave energy is applied to excite and / or decompose the ashing gas to generate plasma in the processing chamber. Ashing the surface of the object to be processed, ie, the photoresist. In the same manner as ashing, cleaning for removing unnecessary substances attached to the surface of the object to be processed can be performed.

In a microwave plasma processing apparatus,
Since a microwave is used as a gas excitation source, electrons can be accelerated by an electric field having a high frequency, and gas molecules can be efficiently ionized and excited. Therefore, for microwave plasma processing equipment, gas ionization efficiency,
It has the advantages of high excitation efficiency and decomposition efficiency, relatively easy formation of high-density plasma, and high-speed processing at low temperature and high speed. In addition, since the microwave has a property of transmitting through the dielectric, the plasma processing apparatus can be configured as an electrodeless discharge type, and therefore, there is an advantage that a highly clean plasma processing can be performed.

In order to further increase the speed of such a microwave plasma processing apparatus, an electron cyclotron resonance (EC)
R) has also been put to practical use. The ECR is such that when the magnetic flux density is 87.5 mT, the electron cyclotron frequency at which electrons rotate around the lines of magnetic force is:
Coincides with the general microwave frequency of 2.45 GHz,
This is a phenomenon in which electrons are resonantly absorbed by microwaves, accelerated, and high-density plasma is generated. In such an ECR plasma processing apparatus, the following four configurations are known as typical configurations of the microwave introduction unit and the magnetic field generation unit.

That is, (i) microwaves propagated through the waveguide are introduced into the cylindrical plasma generation chamber from the opposing surface of the substrate through the transmission window, and are coaxial with the central axis of the plasma generation chamber. (Ii) a microwave transmitted from a waveguide is transmitted from a facing surface of a substrate to be processed into a bell-shaped plasma generating chamber by introducing a diverging magnetic field through an electromagnetic coil provided around the plasma generating chamber. And a magnetic field coaxial with the central axis of the plasma generation chamber is introduced through an electromagnetic coil provided around the plasma generation chamber; (iii) through a digital coil which is a kind of cylindrical slot antenna. A configuration in which microwaves are introduced into the plasma generation chamber from the periphery and a magnetic field coaxial with the central axis of the plasma generation chamber is introduced through an electromagnetic coil provided around the plasma generation chamber (Rigitano method); (iv) Microwaves transmitted through the waveguide are introduced into the cylindrical plasma generation chamber from the opposing surface of the substrate to be processed through a flat slot antenna, and a loop-shaped magnetic field parallel to the antenna plane is applied to the back of the planar antenna. (Planar slot antenna system).

In the specification of US Pat. No. 5,034,086, a radial line slot antenna (RLS) is disclosed.
A plasma processing apparatus using A) is disclosed.

[0010] Alternatively, Japanese Patent Application Laid-Open No. H5-290995, the specification of US Patent No. 5,359,177, EP
Japanese Patent No. 0564359 discloses a plasma processing apparatus using an annular waveguide with a termination.

Apart from these, as an example of a microwave plasma processing apparatus, an apparatus using an annular waveguide having a plurality of slots formed on an inner surface thereof has been recently proposed as a uniform and efficient introduction apparatus for microwaves. (Japanese Patent Laid-Open No. 5-34)
No. 5982, U.S. Pat. No. 5,538,699).

This microwave plasma processing apparatus is shown in FIG.
FIG. 28 shows the microwave supply means.

Reference numeral 501 denotes a plasma generation chamber, 502 denotes a dielectric window for separating the plasma generation chamber 501 from the atmosphere side, and 503 denotes a slotted endless ring having a cylindrical outer shape for supplying microwaves to the plasma generation chamber 501. Waveguide, 505
Is a gas supply means for plasma generation, 511 is a processing chamber connected to the plasma generation chamber 501, 512 is an object to be processed, 513
514 is a heater for heating the substrate 512, 515 is a processing gas supply means, 516 is an exhaust port, 521 is a block for distributing microwaves to the left and right, 5
Reference numeral 22 denotes a slot provided on the curved surface 523. Also, 5
24 is a partition plate, and 525 is a microwave introduction port.

The generation and processing of plasma are performed as follows.

The inside of the plasma generation chamber 501 and the inside of the processing chamber 511 are evacuated via an exhaust system (not shown). Subsequently, a plasma generation gas is introduced into the plasma generation chamber 501 at a predetermined flow rate through the gas supply port 505.

Next, a conductance valve (not shown) provided in an exhaust system (not shown) is adjusted to
01 is maintained at a predetermined pressure. Desired power is supplied from a microwave power supply (not shown) into the plasma generation chamber 501 via the annular waveguide 503.

At this time, the microwave introduced into the annular waveguide 503 is split right and left by the distribution block 521, and propagates in the tube with a guide wavelength longer than the free space wavelength. Microwaves are supplied to the plasma generation chamber 501 from the slots 522 provided for every ま た は or の of the guide wavelength, through the dielectric window 502, and generate plasma 527.

At this time, if the processing gas is supplied into the processing chamber 511 through the processing gas supply pipe 515, the processing gas is excited by the generated high-density plasma, and
The surface of the object to be processed 512 placed on the surface 13 is processed.

By using such a microwave plasma processing apparatus, a microwave power of 1 kW or more and uniformity within ± 3% in a space having a diameter of about 200 mm can be obtained.
Since high-density low-potential plasma having an electron density of 10 ¹² / cm ³ or more, an electron temperature of 3 eV or less, and a plasma potential of 20 V or less can be generated, a gas can be sufficiently reacted and supplied to an object to be processed in an active state. Since surface damage of the object to be processed is also reduced, high-quality and high-speed processing can be performed even at a low temperature.

However, using a microwave plasma processing apparatus for generating high-density low-potential plasma as shown in FIG.
When processing is performed in a high-pressure region of 00 mTorr (about 13.3322 Pa) or more, plasma diffusion is suppressed, so that plasma is localized in the periphery and the processing speed of the central portion of the base may decrease.

Japanese Patent Application Laid-Open No. 7-90591 discloses a plasma processing apparatus using a disk-shaped microwave introducing device. In this apparatus, a gas is introduced into a waveguide, and the gas is emitted from a slot provided in the waveguide toward a plasma generation chamber.

[0022]

SUMMARY OF THE INVENTION Japanese Patent Application Laid-Open No. 7-90591
In the device described in the publication, the supply pressure of gas, the conductance and conductance of the slot, the conductance of the slot, the exhaust pressure, and the like must be precisely adjusted so that plasma is not generated in the waveguide. Therefore, it is very difficult to design an apparatus that can be commonly used for any of CVD, etching, ashing, and the like having different optimum pressures.

In order to process a recently required surface of a 12-inch wafer having a diameter of 305 mm (sometimes referred to as a 300 mm wafer) or a glass substrate having an area corresponding thereto, it is necessary to have a uniform large area and a thin high density. A layer of plasma is required.

For this purpose, it is necessary to further improve the structure of the gas supply means and / or the structure of the microwave supply means.

[0025]

SUMMARY OF THE INVENTION A first object of the present invention is to:
An object of the present invention is to provide a microwave supply device capable of obtaining a uniform microwave radiation intensity distribution.

A second object of the present invention is to provide a microwave feeder capable of generating a thin layer of a high-density plasma that is uniform, large in area and large.

A third object of the present invention is to provide a microwave supply device capable of plasma processing a wafer having a diameter of 300 mm or more or a substrate having a large area corresponding to the wafer.

According to the present invention, an annular waveguide having a planar H-plane having a plurality of slots provided apart from each other and a rectangular cross section perpendicular to the direction in which microwaves travel is provided. And a microwave supply device for supplying microwaves from the plurality of slots provided on the planar H-plane of each annular waveguide.

According to the present invention, a plurality of endless annular waveguides having different circumferential lengths are arranged concentrically,
The microwave feeder is characterized in that the planes are made the same plane and a plurality of slots are provided therein.

Thus, a microwave having a uniform and large-area intensity distribution can be radiated and supplied.

[0031]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows main components of a plasma processing apparatus according to a preferred embodiment using a microwave supply of the present invention.

Reference numeral 1 denotes a container whose inside can be depressurized, 2 a holding means for holding the object to be processed thereon, and 3 a microwave supply means for supplying a microwave for generating plasma in the container 1 ( A microwave supplier or a microwave antenna).

Reference numeral 4 denotes a dielectric window, and 7 denotes gas supply means for supplying gas into the container 1.

FIG. 2 is a sectional view of a plasma processing apparatus constituted by using the components shown in FIG.

The microwave supply device 3 has an H surface 3c having a plurality of slots 3b provided apart from each other, a rectangular cross section perpendicular to the microwave traveling direction (a direction perpendicular to the paper in FIG. 2), Is provided.

The microwaves introduced into the microwave supply device 3 from the microwave introduction port 13 change their courses in directions opposite to each other by the distributor 10 such as an E-branch block, and propagate in the annular waveguide 3a. To go.

The annular waveguide 3a looks like a single rectangular waveguide in which the E-plane is bent and both ends are connected.

In the course of propagation and traveling in the annular waveguide 3a, a plurality of slots 3b provided in the lower H-plane 3c
The microwave is radiated from.

The microwave radiated from each slot 3 b passes through the dielectric window 4 below the microwave supplier 3 and is supplied to the plasma generation space 9 in the container 1.

The inside of the plasma generating space 9 in the container 1 is evacuated by an exhaust means (not shown) communicating with the exhaust path 8 and is in a reduced pressure state. Also, from the gas discharge port 7a of the gas supply means 7,
Gas is released into the plasma generation space 9.

Therefore, a glow discharge is generated by the microwave supplied into the plasma generation space 9, and the constituent molecules of the gas are ionized or become active species. The plasma is generated in a donut shape below the slot, or in a layer shape (disc shape) continuous with the lower surface of the H-plane.

The gas discharge port 7a of the gas supply means 7 is provided so as to discharge gas toward the H surface 3c of the annular waveguide 3a of the microwave supply device 3.

Therefore, the gas discharged from the gas discharge port 7a passes through the high-density plasma region below the slot 3b,
It heads near the center 0 of the microwave supplier 3.

Therefore, the space 9 where the slot 3b does not exist
The active species of the gas or the ions of the gas are also sufficiently supplied to the vicinity of the center 0.

For this reason, uniform plasma processing can be performed over the entire surface of the object W to be processed.

FIG. 3 is a schematic diagram for explaining the propagation of microwaves in the annular waveguide of the microwave supplier and the state of microwave radiation from the slots.

FIG. 3A shows a state when the annular waveguide is viewed from above, FIG. 3B shows a cross section taken along the line BB ′, and FIG. 3A (c) shows a cross section taken along the line CC ′. Is shown.

The vicinity of the microwave inlet 13 is an equivalent circuit of an E-plane branch, and the microwave introduced from the microwave inlet 13 travels in such a way as to be distributed clockwise d ₂ and counterclockwise d _1. change. Each slot is provided so as to intersect with the traveling directions d ₁ and d _{2 of} the microwave, and the microwave travels while emitting the microwave from the slot.

Since the annular waveguide is endless, the directions d ₁ ,
Microwaves propagating to d ₂ interfere with each other to generate a standing wave of a predetermined mode. Reference numeral 3g denotes a ring (ring) formed by connecting the centers of the waveguides. If this length, that is, the circumference is an integral multiple of the guide wavelength (the guide wavelength), a standing wave is easily generated. .

FIG. 3B shows a plane perpendicular to the traveling direction of the microwave, and the upper and lower surfaces 3c of the waveguide are formed by electric fields EF.
H plane perpendicular to the direction of the waveguide.
d is an E plane parallel to the direction of the electric field EF.

The cross section of the waveguide perpendicular to the microwave traveling direction is a rectangular cross section.

From the microwave inlet 13 to the annular waveguide 3a
The microwave MW introduced into the inside is divided into two right and left sides in the figure by the distributor 10, and propagates with a guide wavelength longer than free space.

In the figure, EF indicates an electric field vector perpendicular to the direction in which the microwave travels and perpendicular to the H plane of the waveguide 3a. For example, the leakage wave EW radiated from the slot 3b provided for every 1/2 or 1/4 of the guide wavelength through the dielectric window 4 generates plasma P1 near the slot 4. Also, the microwave incident on the straight line perpendicular to the inner surface 524S of the dielectric window 4 at an angle equal to or larger than the Brewster angle is totally reflected by the inner surface 524S of the dielectric window 4, and the surface wave SW is applied to the inner surface 524S of the dielectric window 4. Propagate as The plasma P2 is generated by the electric field exuding from the surface wave SW.

The gas is excited by the generated high-density plasma to process the surface of the workpiece W.

By using such a plasma processing apparatus, a microwave power of 1 kW or more and a diameter of 300 m
A high-density low-potential plasma with an electron density of 10 ¹² / cm ³ or more, an electron temperature of 3 eV or less, and a plasma potential of 20 V or less can be generated in a large-diameter space of m or more with uniformity of ± 3% or less. It can be supplied to the surface to be processed in an activated state. In addition, when the pressure is 2.7 Pa and the microwave power is 2 kW, it is impossible to detect the current by the microwave at a position 8 to 10 mm away from the inner surface of the dielectric window. This means that a very thin layer of plasma is created. Accordingly, substrate surface damage due to incident ions is reduced, so that high-quality and high-speed processing can be performed even at a low temperature.

FIG. 4 shows the position of the slot of the microwave supply device, the position of the gas discharge port, and the position of the object to be processed.

1w indicates a distance from one end to the other end of the object W (an interval in a direction parallel to the H plane), and for a disk-shaped object such as a Si wafer, its diameter is Is equivalent to For an 8-inch wafer, lw is about 200m
m. In the case of a square object to be processed such as a glass substrate, the length corresponds to the side, that is, the vertical or horizontal length.

In FIG. 4A, lg is a distance (an interval in a direction parallel to the H plane) from one gas discharge port to another gas discharge port at a position facing the gas discharge port.
g is longer than the distance lw.

Ls represents the length of one slot,
lso indicates a distance (an interval in a direction parallel to the H plane) from the outer end of one slot to the outer end of the other slot at a position facing the slot, and satisfies the relationship lsoｓlg.

More preferably, in the embodiment of the present invention, the relationship of l ₁ <l ₂ should be satisfied in the direction perpendicular to the H plane where the slots are provided. Wherein l ₁ denotes the distance from the dielectric window lower surface (inner surface) immediately below the slot until gas outlet 7a (normal direction interval).

Reference numeral ₂ denotes a distance from the gas discharge port 7a to the surface to be processed of the workpiece W (interval in the normal direction).

As described above, by setting the position of the gas discharge port closer to the dielectric window 4 than the workpiece W, the gas excitation efficiency or decomposition efficiency can be further improved.

FIG. 4B shows the position of the slot of the microwave supply means, the position of the gas discharge port, and the position of the object to be processed, as in FIG. 4B. It is a modification example of the example of (a).

1w indicates the distance from one end to the other end of the object W, and corresponds to the diameter of a disk-shaped object such as a Si wafer. For a 12-inch wafer, lw is about 300 mm. In the case of a square object to be processed such as a glass substrate, the length corresponds to the side, that is, the vertical or horizontal length.

Lg is the distance from one gas outlet to the gas outlet at a position opposite to it, and the distance lg
Is shorter than the distance lw. Thus, the released gas easily flows to the vicinity of the center 0 through the region having a high plasma density immediately below the slot.

Ls indicates the length of one slot, lso indicates the distance from the outer end of one slot to the outer end of the other slot at a position facing the slot, and lso <lg Satisfy the relationship.

In the embodiment of the present invention, it is more preferable that the relationship of l ₁ <l ₂ is satisfied in a direction perpendicular to the H plane where the slots are provided.

Here, l ₁ indicates the distance from the lower surface (inner surface) of the dielectric window immediately below the slot to the gas outlet 7a.

Reference numeral ₂ denotes a distance from the gas discharge port 7a to the surface of the workpiece W to be processed.

As described above, by setting the position of the gas discharge port closer to the dielectric window 4 than the target object W, the gas excitation efficiency or decomposition efficiency can be further improved.

In particular, an apparatus satisfying the relationship shown in FIG.
It is more suitable for processing a large-area object such as a wafer having a diameter of 300 mm or more or a substrate corresponding thereto as compared with FIG.

(Microwave Supply Means) As a microwave supply means used in the present invention, as shown in FIGS. 1 to 3, an annular waveguide (annular waveguide) having a rectangular cross section and having a plurality of slots on its H surface. Tube) is preferably used. More preferably, it is desirable to have no end.

The example of FIG. 1 has a ring-shaped outer shape obtained by bending a rectangular waveguide into an annular shape, but the microwave supply means used in the present invention has a disk-shaped outer shape as shown in FIG. You may have.

FIG. 5 shows a microwave supplier according to a reference example.

The microwave supply device shown in FIG. 5 has a first conductive member 32 in which an endless annular concave portion 33 and an opening serving as a microwave introduction port 13 are formed, and a relatively thin member in which a plurality of slots 3b are formed. It is an assembly with a disc-shaped second conductive member 31.

(A) shows a cross section, (b) shows a first conductive member 32, and (c) shows a second conductive member 31, respectively.

If the H-plane having the slot 3b can be detached, the following effects can be obtained.

If a plurality of types of second conductive members 31 having different shapes, sizes, the number of slots, distribution of slots, etc. are prepared in advance, the second conductive members 3
1 can be replaced with an appropriate one in accordance with the microwave radiation intensity or plasma treatment that requires the use of the same. As a result, the degree of freedom in designing the microwave feeder is increased, and the microwave feeder can be manufactured at low cost.

The disk-shaped second conductive member 31 is indicated by a broken line D
In L, of course, the center portion may be hollowed out and processed into a donut shape.

The second conductive member 31 is assembled by being sandwiched between the first conductive member 32 and the above-described dielectric window.

FIG. 6 shows another microwave supply means used in the present invention. FIG. 6A shows a vertical cross section, and FIG. 6B shows a horizontal cross section taken along the line DD '.

This microwave supplier 3 has a rectangular annular waveguide 3a with a sharp corner as shown in FIG. 3B, and is used for a rectangular substrate such as a glass substrate for a flat panel display or a solar cell. This is suitable when the web substrate described above is used as the object to be processed.

In the microwave supply means 3, the microwave introduced from the rectangular waveguide 5 is divided into a clockwise d ₂ and a counterclockwise d ₁ by the distributor 10 while traveling in a plane. Microwaves are emitted from slots 3b provided on the H-plane 3c. Microwaves traveling in both directions d ₁ and d ₂ attenuate while interfering with each other. Waveguide 3
When the propagation of the microwave in a becomes stable, a standing wave is generated in the waveguide 3a.

The microwave radiated from the slot 3b is supplied to the plasma generating space in the container 1 through the dielectric window 4 based on the principle described with reference to FIG.

In the container 1, gas is discharged from the gas discharge port 7a provided obliquely, and is excited immediately below the dielectric window 4 and flows as indicated by an arrow GF in the figure.

As the material of the member constituting the annular waveguide used in the microwave plasma processing apparatus of the present invention described above, any material can be used as long as it is a conductor. Al, C with high
u, Ag / Cu-plated stainless steel or the like is optimal. The inlet to the annular waveguide used in the present invention is provided on the H-plane as described above and is perpendicular to the H-plane as long as microwaves can be efficiently introduced into the microwave propagation space in the annular waveguide. The microwave may be introduced into the transmission space and divided into two in the left and right direction of the propagation space by the introduction unit, but may be introduced from the tangential direction of the propagation space parallel to the H plane.

The shape of the slot used in the present invention may be rectangular or elliptical as long as the length in the direction perpendicular to the microwave propagation direction is at least １ ／ of the wavelength in the waveguide (wavelength in the tube). It may be S-shaped, cross-shaped or array-shaped. The slot interval used in the present invention is not particularly limited, but the slots are arranged at least at intervals of a half of the guide wavelength so that the electric field crossing the slot due to interference is strengthened. In particular, 1/1 of the guide wavelength
2 is optimal. The slots are, for example, 1 to 1
A vertically long opening having a width of 0 mm and a length of 40 to 50 mm is preferable. It is also preferable that the slots are arranged radially with respect to the center of the ring of the annular waveguide, for example.

A specific example will be described with reference to the drawings.

FIG. 7 shows the shapes of various slots used in the microwave supply means of the present invention.

FIG. 7A shows the traveling direction d _{1 of the} microwave.
(D ₂ ) is a slot having a length l ₁ where the longitudinal direction intersects with (d ₂ ), and is provided apart from each other with a pitch l _P.

FIG. 7B shows the traveling direction d _{1 of the} microwave.
(D ₂ ) is a slot that intersects with a tilt angle θ and has a component l in a direction perpendicular to the traveling direction d ₁ (d ₂ ).
₁ and are spaced apart from each other with a pitch l _P.

FIG. 7C shows an S-shaped slot.

As described above, the slot arrangement interval, that is, the pitch l _P, is １ ／ or 1/1 of the waveguide wavelength (guide wavelength).
A value of 4 is more preferable.

It is more preferable that the length l ₁ of the slot in the direction perpendicular to the traveling direction of the microwave is in the range of １ ／ to ／ of the guide wavelength.

Further, it is not necessary that all the slots are arranged at equal intervals, for example, at a half pitch of the guide wavelength, and as shown in FIG.
They may be arranged at intervals longer than / 2.

A broken line 3g in the figure is a ring (distance) formed by connecting the centers of the annular waveguides, and it is preferable that the circumference is an integral multiple of the guide wavelength.

Further, in order to improve the uniformity of the microwave emission intensity, it is preferable that the power of the inputted microwave is such that it can propagate in the annular waveguide one or more rounds, more preferably two or more rounds. In this case, it may be better to omit the distributor 10.

(Dielectric Window) The dielectric window used in the present invention is formed of a shape or material that can transmit microwaves of 0.8 to 20 GHz but does not transmit gas.

The shape may be a disk that covers the entire lower surface of the H plane as shown in FIG. 1, or a donut shape, or may correspond to each slot so as to cover only the slot portion. May be provided. However, in order to facilitate the assembly of the vacuum container and to increase the degree of freedom in designing the slot, it is more preferable to configure the slot with a plate-shaped member common to the slots.

As the dielectric used in the microwave plasma processing apparatus and the processing method of the present invention, silicon oxide-based quartz, various glasses, Si ₃ N ₄ , NaCl, K
Cl, LiF, CaF ₂ , BaF ₂ , Al ₂ O ₃ , Al
Inorganic substances such as N and MgO are suitable, but films and sheets of organic substances such as polyethylene, polyester, polycarbonate, cellulose acetate, polypropylene, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyamide, and polyimide are also applicable.

In particular, a plate made of quartz, alumina or the like is preferably used.

(Container) As the container used in the present invention, a container capable of reducing the pressure to a pressure lower than the atmospheric pressure is used for the purpose of replacing gas or generating plasma inside.

The container is made of a conductor such as aluminum or stainless steel, an insulator such as quartz or silicon carbide, or a combination of a conductive member and an insulating member.

In the case where an insulator is used, a container can be formed integrally with the above-described dielectric window.

The inner surface of the conductive container may be covered with an insulating film.

Then, the inside is at least 0.1 mTorr.
The pressure is reduced to about r (about 1.33 × 10 ⁻² Pa).

(Gas Supply Means) As the gas supply means used in the present invention, a gas supply means having a discharge port for discharging gas toward the H surface of the microwave supply means is used. By forming the gas discharge path communicating with the gas discharge port perpendicularly or obliquely to the H plane, the direction of the gas discharge port can be easily determined.

The gas outlet may be a plurality of openings provided apart from each other along the annular waveguide as shown in FIG. 1 or may be formed in the annular waveguide as shown in FIG. It may be a slit provided along.

Alternatively, a plurality of gas supply pipes can be provided as shown in FIG.

It is more preferable that the position of the gas discharge port in the direction parallel to the H plane is as shown in FIG. 4, thereby facilitating uniform processing of a large area.

These gas supply means are connected to a gas cylinder or a vaporizer via a mass flow controller (not shown), a valve, a joint or the like.

The holding means for the object to be processed may have a flat holding surface or may be held at several points by pins or the like. The holding surface or the holding point may be a conductor or an insulator. And other various materials. The holding means further includes
A heating unit and a cooling unit may be provided. Further, in order to facilitate loading and unloading of the object to be processed, a configuration having lift pins that can be moved up and down is also preferable as the holding means.

In addition, in order to control the movement and position of the particles in the plasma, it is preferable to provide a bias applying means in the holding means so that a DC or AC bias can be applied to the object to be processed.

In the microwave plasma processing apparatus and the processing method of the present invention, a magnetic field generating means may be used for processing at a lower pressure. As the magnetic field used in the plasma processing apparatus and the processing method of the present invention, a mirror magnetic field or the like can be applied. The magnetic flux density is optimally a magnetron magnetic field larger than the magnetic flux density of the magnetic field near the substrate. As the magnetic field generating means, a permanent magnet other than a coil can be used.
When using a coil, other cooling means such as a water cooling mechanism or air cooling may be used to prevent overheating.

In order to improve the quality of the treatment, the surface of the base may be irradiated with ultraviolet light. As a light source, any light source that emits light absorbed by a substrate to be processed or a gas attached to the substrate can be used. ArF, KrF, or Xe
An excimer laser using a dimer such as Cl, an excimer lamp, a rare gas resonance line lamp, a low-pressure mercury lamp and the like are suitable.

In the present invention, 0.8 GHz
It is preferable to use a plasma generator such as a magnetron that generates a microwave selected from the range of from about 20 GHz to about 20 GHz. Propagation and supply to the feeder.

As the microwave introduced into the inlet of the microwave supply device, a TE mode microwave is preferably used. In particular, a microwave called TE _n0 mode or H _0n mode (where n is a natural number) is introduced. Is more preferable.

In the annular waveguide, the electric field vector of the microwave is perpendicular to the plane with the slots, and this plane becomes the H plane.

[0119] Also in the annular waveguide 3a, but the microwave is propagated in the TE ₁₀ mode (H ₀₁ mode), since eventually sometimes standing waves occur, the waveguide 3 in this case
The propagation mode of the microwave in a can be regarded as another mode.

Next, the processing method according to the present invention will be described.

First, the container 1 is opened, the object is placed on the object holding means 2, and the container 1 is closed (step S1 in FIG. 10).

Next, the pressure in the container 1 is reduced from atmospheric pressure to about 1.3 Pa or less by a vacuum pump (not shown) (step S2 in FIG. 10).

The gas outlet 7a of the gas supply means 7
To release the gas into the container 1 (step S3 in FIG. 10).

When the pressure in the container 1 is stabilized, a microwave oscillator (not shown) is turned on to generate a microwave, and the microwave is supplied into the container 1 from the microwave introducing means 3 of the present invention (step shown in FIG. 10). S4).

The plasma emission is observed through a monitor window provided as necessary in the container 1.

When a predetermined processing time has elapsed, the supply of the microwave is stopped (step S5 in FIG. 10).

The gas in the container 1 is purged with nitrogen for purging Ar, H
The gas is replaced with a gas such as e, Ne or clean air, and the pressure is returned to the atmospheric pressure (step S6 in FIG. 10).

Then, the container 1 is opened and the object is carried out (step S7 in FIG. 10).

The above processing may be repeated for each object to be processed.

In the microwave plasma processing method of the present invention, the pressure in the plasma processing chamber is 0.1 mTorr (about 0.133 Pa) to 10 Torr (about 1330 Pa).
, More preferably 1 mTorr (about 0.133 Pa) to 10 m in the case of CVD, plasma polymerization or surface modification.
0 mTorr (about 13.3 Pa), and 0.5 mTorr (about 0.067 Pa) to 50 mTorr for etching.
rr (approximately 6.67 Pa), ashing range 100
mTorr (about 13.3 pa) to 10 Torr (about 1
330 Pa). In the case of cleaning, the pressure is preferably set to 0.067 Pa to 13.3 Pa.

The formation of the deposited film by the microwave plasma processing method of the present invention can be performed by appropriately selecting a gas to be used by using Si ₃ N ₄ , SiO ₂ , Ta ₂ O ₅ , TiO ₂ , T _{2
iN, Al 2 O 3, AlN} , an insulating film such as _{MgF 2, AlF 3, a-} Si ( amorphous silicon), poly
Semiconductor films such as -Si (polysilicon), SiC, GaAs, metal films such as Al, W, Mo, Ti, Ta, etc .;
Various deposited films such as iN, TiW, and TiSiN can be efficiently formed.

The target object 112 to be processed by the plasma processing method of the present invention may be a semiconductor, a conductive one, or an electrically insulating one.
Then, the surface may be a semiconductor, an insulator, a conductor, or a composite surface of these three.

As the conductive substrate, Fe, Ni, Cr,
Al, Mo, Au, Nb, Ta, V, Ti, Pt, Pb
And alloys thereof, such as brass and stainless steel.

Examples of the insulating substrate include SiO ₂ -based quartz and various glasses, Si ₃ N ₄ , NaCl, KCl, LiF,
Inorganic substances such as CaF ₂ , BaF ₂ , Al ₂ O ₃ , AlN, MgO, etc., films and sheets of organic substances such as polyethylene, polyester, polycarbonate, cellulose acetate, polypropylene, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyamide, polyimide, etc. Is mentioned.

As a gas used for forming a thin film on a substrate by the CVD method, a-Si, poly-s
i, when forming a Si-based semiconductor thin film such as SiC: S
Source gases containing i atoms include SiH ₄ , Si ₂
Inorganic silanes such as H ₆ , tetraethylsilane (TE
S), tetramethylsilane (TMS), dimethylsilane (DMS), dimethyldifluorosilane (DMDF)
S), organic silanes such as dimethyldichlorosilane (DMDCS), SiF ₄ , Si ₂ F ₆ , Si ₃ F ₈ , Si
HF ₃ , SiH ₂ F ₂ , SiCl ₄ , Si ₂ Cl ₆ , S
iHCl ₃ , SiH ₂ Cl ₂ , SiH ₃ Cl, SiCl ₂
Examples include halosilanes such as F ₂ and the like, which are in a gaseous state at normal temperature and normal pressure, or those which can be easily gasified. In this case, the additive gas or carrier gas which may be introduced by being mixed with the Si source gas is H ₂ , He, N
e, Ar, Kr, Xe, and Rn.

Si_Three N_Four , SiO_Two Si compound such as
As a raw material containing Si atoms when forming thin films
Is SiH_Four , Si_Two H₆ Inorganic silanes, such as tetra
Ethoxysilane (TEOS), tetramethoxysilane
(TMOS), octamethylcyclotetrasilane (OM
CTS), dimethyldifluorosilane (DMDFS),
Organic sila such as dimethyldichlorosilane (DMDCS)
, SiF_Four , Si_Two F ₆ , Si_Three F₈ , SiHF
_Three , SiH_Two F_Two , SiCl_Four , Si_Two Cl₆ , SiH
Cl_Three , SiH_Two Cl_Two , SiH_Three Cl, SiCl_Two F
_Two Such as halosilanes are in a gaseous state at normal temperature and pressure
Easier to gasify by or vaporizer or bagler
What can be done. Also in this case introduced at the same time
The nitrogen source gas or oxygen source gas is_Two ,
NH_Three , N_Two H_Four , Hexamethyldisilazane (HMD
S), O_Two , O_Three , H_Two O, NO, N_Two O, NO_Two Such
Is mentioned.

When forming a metal thin film such as Al, W, Mo, Ti, Ta, and TiW, the raw materials containing metal atoms include trimethylaluminum (TMAl), triethylaluminum (TEAl), and triisobutylaluminum (TIBAl). , Dimethylaluminum hydride (DMAlH), tungsten carbonyl (W (C
O) ₆ ), molybdenum carbonyl (Mo (CO) ₆ ),
Organic metals such as trimethylgallium (TMGa) and triethylgallium (TEGa), AlCl ₃ , WF ₆ , T
Metal halides such as iCl ₃ and TaCl ₅ are exemplified. In this case, it may be introduced by being mixed with the above-mentioned Si source gas. Examples of the additive gas or the carrier gas include H ₂ , He, Ne, Ar, Kr, Xe, and Rn.

Al ₂ O ₃ , AlN, Ta ₂ O ₅ , TiO
Raw materials containing metal atoms when forming a metal compound thin film such as ₂ , TiN, WO ₃ , TiW, TiSiN include trimethyl aluminum (TMAl), triethyl aluminum (TEAl), triisobutyl aluminum (TIBAl), and dimethyl aluminum. Hydride (DMAlH), tungsten carbonyl (W (C
O) ₆ ), molybdenum carbonyl (Mo (CO) ₆ ),
Organic metals such as trimethylgallium (TMGa) and triethylgallium (TEGa), AlCl ₃ , WF ₆ , T
Metal halides such as iCl ₃ and TaCl ₅ are exemplified. In this case, the oxygen source gas or the nitrogen source gas introduced simultaneously may be O ₂ , O ₃ , H ₂ O, N
O, N ₂ O, NO ₂ , N ₂ , NH ₃ , N ₂ H ₄ , hexamethyldisilazane (HMDS) and the like.

As the etching gas introduced from the processing gas inlet 115 for etching the substrate surface, F ₂ , CF ₄ , CH ₂ F ₂ , C ₂ F ₆ , CF ₂ Cl
₂ , SF ₆ , NF ₃ , Cl ₂ , CCl ₄ , CH ₂ Cl
₂ , C ₂ Cl _{6 and the} like.

As the ashing gas introduced from the processing gas inlet 115 for removing ashing such as photoresist from organic components on the substrate surface, O ₂ , O ₃ , H
₂ O, NO, N ₂ O, NO _{2 and the} like.

In the case of cleaning, the above etching gas, ashing gas, hydrogen gas or inert gas is used.

When the microwave plasma processing apparatus and the processing method of the present invention are applied to surface modification, for example, Si, Al, T
Oxidation treatment or nitridation treatment of the substrate or surface layer made of i, Zn, Ta, or the like, and doping treatment of B, As, P, or the like can also be performed. Further, the film forming technique employed in the present invention can be applied to the cleaning method as described above. In that case, it can be used for cleaning oxides, organic substances, heavy metals, and the like.

The oxidizing gas used when the substrate is subjected to an oxidizing surface treatment is O ₂ , O ₃ , H ₂ O, NO, N ₂ O, NO ₂
And the like. In addition, as the nitriding gas when the substrate is subjected to the nitriding surface treatment, N ₂ , NH ₃ , N ₂ H ₄ , hexamethyldisilazane (HMDS) and the like can be mentioned.

In particular, the gas for cleaning / ashing introduced from the gas inlet 105 when cleaning organic substances on the surface of the substrate or ashing and removing organic components such as photoresist on the surface of the substrate is O
₂ , O ₃ , H ₂ O, NO, N ₂ O, NO _{2 and the} like. The cleaning gas introduced from the gas introduction port for plasma generation when cleaning the inorganic substance on the substrate surface is F ₂ , CF ₄ , CH ₂ F ₂ , C ₂ F
₆ , CF ₂ Cl ₂ , SF ₆ , NF _{3 and the} like.

The microwave power supplied from the microwave power source radiates the microwave from the slot in the annular waveguide one or more rounds, preferably two or more rounds, in order to improve the uniformity of the microwave radiation intensity. The value should be sufficient to allow propagation. In this case, it is better not to provide a distributor.

(Plasma Processing Apparatus) Hereinafter, the microwave plasma processing apparatus will be described more specifically.

(First Plasma Processing Apparatus) A specific example of the first plasma processing apparatus is as described with reference to FIGS.

(Second Plasma Processing Apparatus) An example of a microwave plasma processing apparatus using a two-partition interference type flat annular waveguide with slots will be described with reference to FIG. 1
09 is a plasma generation chamber in the container 101, 104 is a dielectric window for separating the plasma processing chamber 109 from the atmosphere side, 103
Is a microwave supply means tube for supplying microwaves into the plasma generation chamber 109, and 105 is a flat slotted H
A rectangular waveguide 103a for introducing microwaves into the annular waveguide 103b having a surface;
A waveguide, which is a microwave propagation space having a rectangular cross section through which microwaves propagate, 103b is a slot for introducing microwaves, W is an object to be processed, 102 is a holding unit, 114 is a heater as a heating unit, and 107 is a heater. Gas supply means, 1
08 is an exhaust port.

In this plasma processing apparatus, the gas supply system has at least a gas source 21 such as a gas cylinder or a vaporizer or a bubbler, a valve 22, and a mass flow controller 23. The amount of gas supplied to 109 is controlled. Then, the gas is discharged from the gas discharge port 107a facing obliquely upward.

The gas exhaust system has at least an exhaust conductance control valve 26, an opening / closing valve 25, and a vacuum pump 24.
The pressure at the time of processing in the plasma generation chamber 109 is controlled by 6.

Reference numeral 6 denotes a microwave power supply.
It has a microwave oscillator such as a magnetron, and in addition, adjusting means such as a tuner, an isolator, and a mode converter are additionally provided as necessary.

The generation and processing of plasma are performed as follows. The object W is placed on the substrate holding means 102, and the substrate W is heated to a desired temperature using the heater 114. Plasma generation chamber 10 via an exhaust system (not shown)
The inside of 9 is evacuated. Subsequently, a plasma processing gas is introduced into the plasma generation chamber 109 at a predetermined flow rate via the gas supply means 107. Next, a conductance valve (not shown) provided in an exhaust system (not shown) is adjusted to maintain the inside of the plasma generation chamber 109 at a predetermined pressure. A desired power is supplied from a microwave power supply (not shown) to the T
It is introduced into the circular waveguide 103 E ₁₀ mode. The introduced microwave is split into two by the splitter 110 and the space 103
Propagate in a. The divided microwaves interfere with each other to generate a standing wave. The microwave is １ ／ of the guide wavelength
In each case, the electric field across slot 103b is
Plasma generation chamber 1 through dielectric window 104
09. The electrons are accelerated by the electric field of the microwave supplied into the plasma generation chamber 109, and a plasma P is generated, for example, in the upper part of the plasma processing chamber 109. At this time, the processing gas is excited by the generated high-density plasma, and processes the surface of the processing target substrate W placed on the holding means 102.

The dielectric window 104 is made of synthetic quartz having a diameter of 299 mm and a thickness of 12 mm. The annular waveguide 103 with a flat slot has an inner wall cross-sectional dimension of 27 mm × 96 mm.
A is a central diameter it is capable of propagating microwaves of TE ₁₀ mode 202 mm. A1 is used for the material of the annular waveguide 103 with a slot in the form of a plate in order to suppress the propagation loss of the microwave. Microwaves are applied to the H-plane of the annular waveguide 103 with a slot in the form of a plate.
A slot is formed for introduction into the device. The shape of the slot is a rectangle having a length of 42 mm and a width of 3 mm, and is radially formed at a half interval of the guide wavelength. Guide wavelength is a frequency of microwave to be used depends on the dimensions of the cross section of the waveguide, approximately in the case of using a microwave frequency 2.45 GHz _Z, and a waveguide of the dimensions 159m
m. Used annular waveguide 103 with flat slot
In the figure, eight slots 103b are formed at intervals of about 79.5 mm. In the annular waveguide 103 with a flat slot, a 4E tuner, a directional coupler, an isolator, and 2.
45GH microwave power having a frequency of _Z (not shown) are bonded in this order, so as to introduce microwave TE ₁₀ mode.

Using the microwave plasma processing apparatus shown in FIG. 11, an Ar flow rate of 500 sccm and a pressure of 10 mT
Plasma was generated under the conditions of orr, 1 Torr, and microwave power of 1.5 kW, and the obtained plasma was measured. The plasma measurement was performed by the single probe method as follows. Apply a voltage of -50 to the probe.
The current flowing through the probe was measured by an IV measuring instrument, and the electron density, electron temperature and plasma potential were calculated from the obtained IV curve by the method of Langmuir et al. As a result, the electron density is 10 m
In the case of Torr, 1.3 × 10 ¹² / cm ³ ± 2.1% (φ
Within 200 planes) 7.2 × 10 ¹¹ / cm at 1 Torr
³ ± 5.3% (within φ200 plane), and it was confirmed that high-density and uniform plasma was formed even in a high-pressure region.

(Third Plasma Processing Apparatus) An example of a microwave plasma processing apparatus using a tangentially-introduced flat annular waveguide with a slot will be described with reference to FIG. 10
9 is a plasma generation chamber, 104 is a dielectric window for separating the plasma processing chamber 109 from the atmosphere side, 103 is a microwave supply means for supplying microwaves to the plasma generation chamber 109, and 205 is an annular waveguide with a flat slot. An introduction unit 10 for introducing microwaves provided in front of the outer periphery of the tube 103;
Reference numeral 3a denotes a microwave propagation space having a rectangular cross section through which the microwave propagates in the annular waveguide 103 having a slot with a flat plate, and 10;
3b is a slot for emitting microwaves provided on the H-plane of the annular waveguide 103 with a slot in the form of a plate, 102 is holding means for the object W, 114 is a heater for heating the object W, and 107 is a member for processing. The gas introduction means 108 is an exhaust port.

In this plasma processing apparatus, the gas supply system has at least a gas source 21 such as a gas cylinder or a vaporizer or a bubbler, a valve 22, and a mass flow controller 23. The amount of gas supplied to 109 is controlled. The gas is discharged from the gas outlet 107a facing obliquely upward.
It is emitted more towards the dielectric window. Further, the gas exhaust system has at least an exhaust conductance control valve 26, an opening / closing valve 25, and a vacuum pump 24, and the exhaust conductance control valve 26 controls the pressure in the plasma generation chamber 109 during processing.

Reference numeral 6 denotes a microwave power supply, which has a microwave oscillator such as a magnetron, and further has adjusting means such as a tuner, an isolator, and a mode converter if necessary. I have.

The plasma processing is as follows.

The object W is placed on the holding means 102, and the object W is heated by the heater 144 to a predetermined temperature.

The interior of the plasma generation chamber 109 is evacuated via an exhaust system (not shown). Subsequently, a plasma processing gas is introduced into the plasma generation chamber 109 at a predetermined flow rate through the processing gas discharge port 107a. Next, a conductance valve (not shown) provided in an exhaust system (not shown) is adjusted to maintain the inside of the chamber 109 at a predetermined pressure. A desired power from a microwave power supply (not shown) is tangentially introduced into the annular waveguide 203 with a flat slot from the introduction unit 205. The introduced TE ₁₀ mode microwaves are 1/1 of the guide wavelength.
The dielectric window 10 is formed through the slot 103b formed every two.
4 and is supplied into the plasma generation chamber 109. Room 1
The microwaves that have not been supplied into the tube 09 but have propagated one round in the tube 103 interfere with each other and are strengthened by the microwaves newly introduced by the introduction unit 205. 109. The electrons are accelerated by the supplied electric field of the microwave, and plasma P is generated above the plasma generation 109. At this time, the processing gas is excited by the generated high-density plasma, and processes the surface of the workpiece W placed on the holding means 102.

The dielectric window 104 is a synthetic quartz plate having a diameter of 299 mm and a thickness of 16 mm. The annular waveguide 103 with a flat slot has an inner wall cross-sectional dimension of 27 mm × 96 mm.
This is the same waveguide as described above, having a rectangular cross section and a center diameter of 202 mm. Annular waveguide 10 with flat slot
All of the materials No. 3 use A1 in order to suppress microwave propagation loss. Annular waveguide 10 with flat slot
A slot for introducing microwaves into the plasma generation chamber 109 is formed in the H plane 3. The shape of the slot is a rectangle having a length of 42 mm and a width of 3 mm, and is radially formed at a half interval of the guide wavelength. Guide wavelength is a frequency of microwave to be used depends on the dimensions of the cross section of the waveguide, approximately in the case of using a microwave frequency 2.45 GHz _Z, and a waveguide of the dimensions 159 mm. In the used annular waveguide 103 with a flat slot,
Eight slots are formed at intervals of about 79.5 mm.
A flat slotted annular waveguide 103, 4E tuner, a directional coupler, an isolator, a microwave power having a frequency of 2.45 GHz _Z (not shown) is joined in this order.

Using the microwave plasma processing apparatus shown in FIG. 12, an Ar flow rate of 500 sccm and a pressure of 10 mT
Plasma was generated under the conditions of orr, 1 Torr, and microwave power of 1.5 kW, and the obtained plasma was measured. The plasma measurement was performed by the single probe method as follows. Apply a voltage of -50 to the probe.
The current flowing through the probe was measured by an IV measuring instrument, and the electron density, electron temperature and plasma potential were calculated from the obtained IV curve by the method of Langmuir et al. As a result, the electron density is 10 m
In the case of Torr, 1.8 × 10 ¹² / cm ³ ± 2.3% (φ
7.7 × 10 ¹¹ / cm at 1 Torr
³ ± 5.6% (within φ200 plane), and it was confirmed that high-density and uniform plasma was formed even in a high-pressure region.

(Fourth Plasma Processing Apparatus) A microwave plasma processing apparatus using an RF bias applying mechanism will be described with reference to FIG. 109 is a plasma generation chamber, 1
04 is a dielectric window for separating the plasma generation chamber 109 from the atmosphere side, 103 is a microwave supply means for supplying microwaves to the plasma generation chamber 109, and 102 is the workpiece W
Holding means 114, a heater for heating the object to be processed,
7 is a gas supply means, 108 is an exhaust port, and 302 is an RF bias applying means.

In this plasma processing apparatus, the gas supply system has at least a gas source 21 such as a gas cylinder or a vaporizer or a bubbler, a valve 22, and a mass flow controller 23. The amount of gas supplied to 109 is controlled. The gas is passed through the dielectric window 10 through the gas outlet 107a.
It is emitted obliquely upward toward 4.

The gas exhaust system has at least an exhaust conductance control valve 26, an opening / closing valve 25, and a vacuum pump 24.
The pressure at the time of processing in the plasma generation chamber 109 is controlled by 6.

Reference numeral 6 denotes a microwave power supply, which has a microwave oscillator such as a magnetron, and in addition, adjusting means such as a tuner, an isolator, and a mode converter are additionally provided as necessary. I have.

The generation and processing of plasma are performed as follows. The workpiece W is placed on the holding means 102 and heated to a desired temperature using the heater 114. Exhaust system (2
4 to 26), the inside of the plasma generation chamber 109 is evacuated. Subsequently, the plasma processing gas is supplied to the gas supply means 10.
7 is introduced into the plasma generation chamber 109 at a more predetermined flow rate. Next, the conductance control valve 26 provided in the exhaust system (24 to 26) is adjusted, and the plasma generation chamber 109 is adjusted.
Is maintained at a predetermined pressure. RF bias applying means 30
RF power is supplied to the holding means 102 by using the microwave power supply 2 and desired power is supplied from the microwave power source 6 through the slot 103 b of the microwave supply means 103.
To the plasma generation chamber 109. Electrons are accelerated by the electric field of the microwave supplied into the plasma generation chamber 109, and plasma is generated in the plasma generation chamber 109. At this time, the processing gas is excited by the generated high-density plasma, and processes the processing surface of the processing target W placed on the holding unit 102. Further, the kinetic energy of ions incident on the object can be controlled by the RF bias.

A microwave plasma processing apparatus using cooling means will be described with reference to FIG. Reference numeral 109 denotes a plasma generation chamber; 104, a dielectric window for separating the plasma generation chamber 109 from the atmosphere; and 203, a microwave supply means for introducing microwaves into the plasma generation chamber 109. Consists of a waveguide. 10
2 is a holding means for the object W, 414 is a cooler for cooling the object, 107 is a gas supply means, 108 is an exhaust port,
02 is an RF bias applying means.

In this plasma processing apparatus, the gas supply system has at least a gas source 21 such as a gas cylinder or a vaporizer or a bubbler, a valve 22, and a mass flow controller 23. The amount of gas supplied to 109 is controlled. The gas is discharged obliquely upward from the gas discharge port.

The gas exhaust system has at least an exhaust conductance control valve 26, an opening / closing valve 25, and a vacuum pump 24.
The pressure at the time of processing in the plasma generation chamber 109 is controlled by 6.

Reference numeral 6 denotes a microwave power supply, which has a microwave oscillator such as a magnetron, and further includes adjusting means such as a tuner, an isolator, and a mode converter as necessary. I have.

The cooling means 414 includes a heat pipe 417 having an inlet pipe 415 for introducing the refrigerant and an outlet pipe 416 for extracting the refrigerant.

The heat generated by heating the workpiece W by etching or sputtering development is released to the outside by the heat pipe 417.

Further, in this plasma processing apparatus, the length of the slot of the microwave
Although the width h of the H-plane of 03a is equal to the width h of the slot 203b, it is also possible to make the length of the slot 203b shorter than the width h as in the slot of the microwave supply means of each embodiment described above.

The generation and processing of plasma are performed as follows. The object W is placed on the holding means 102 and cooled using the cooler 114. The inside of the plasma generation chamber 108 is evacuated via the exhaust system (24 to 26). continue,
The plasma processing gas is supplied into the plasma generation chamber 109 at a predetermined flow rate via the gas supply means 107. Next, the conductance control valve (26) provided in the exhaust system (24 to 26) is adjusted to maintain the inside of the plasma generation chamber 109 at a predetermined pressure. RF power is supplied to the holding means 102 using the RF bias applying means 302 and desired power is supplied from the microwave power source 6 to the microwave supplying means 2.
Introduced into the plasma processing chamber 109 through the dielectric window 104 through the slot 203b of No. 03. Plasma generation 10
Electrons are accelerated by the electric field of the microwave supplied to the inside 9, and plasma is generated in the plasma generation chamber 109. At this time, the processing gas is excited by the generated high-density plasma, and processes the surface of the workpiece W placed on the holding means 102. Further, the kinetic energy of ions incident on the substrate can be controlled by the RF bias. Cooler 4
By using 14, it is possible to suppress overheating of the substrate due to ion incidence, which is a problem when using high-density plasma and high bias.

FIG. 15 is a schematic sectional view showing a plasma processing apparatus.

[0177] Reference numeral 1 denotes a vacuum container which accommodates the object W to be processed and can generate plasma P inside the generation chamber 9, and is a container open to the atmosphere.

Reference numeral 2 denotes a case where the object W is accommodated in the vacuum vessel 1,
It is an object holding means for holding the object, and has a lift pin 2a that can move up and down the object W to be processed.

Reference numeral 3 denotes microwave supply means for supplying microwave energy for generating plasma in the vacuum vessel 1.

Reference numeral 4 denotes a dielectric window for hermetically sealing the inside of the vacuum vessel 1 and transmitting microwaves.

Reference numeral 5 denotes a microwave waveguide, and reference numeral 6 denotes a microwave power supply.

Reference numeral 7 denotes a gas supply path for supplying a processing gas to be converted into plasma by microwaves. The gas supply path 7 has a gas discharge port 7a at the end of a discharge path directed obliquely upward.

The gas supply path 7 communicates with a gas supply system similar to the gas supply systems (21 to 23) in FIGS.

Reference numeral 8 denotes an exhaust passage for exhausting the inside of the vacuum vessel 1, which communicates with the same exhaust system as the exhaust systems (24 to 26) shown in FIGS.

A plasma processing method using the apparatus shown in FIG. 15 is as follows. The processing gas is supplied from the gas supply path 7 into the vacuum vessel 1 evacuated and evacuated to a predetermined pressure.

After the processing gas is released into the space 9 serving as the plasma generation chamber, it flows into the exhaust path 8.

On the other hand, the microwave generated by the microwave power supply 6 is propagated through a coaxial waveguide, a cylindrical waveguide or a rectangular waveguide 5 and supplied to the microwave supply means 3.

The microwave propagates through the endless annular waveguide 3a of the microwave supply means 3.

Since the H-plane 3c of the endless annular waveguide 3a is provided with a vertically elongated slot 3b intersecting with the traveling direction of the microwave, the microwave is transmitted from the slit 3b toward the space 9. Radiated.

The microwave is supplied into the space 9 through the microwave transmitting window 4a.

In the space 9, there is a processing gas.
This processing gas is microwave-excited to generate plasma P.

The surface of the workpiece W is subjected to a surface treatment using this plasma. The plasma P may exist only below the slot as shown in the figure, or may spread over the entire lower surface of the dielectric window 4 depending on the power of the supplied microwave or the pressure in the container.

FIG. 16 is a schematic diagram showing an appearance and a cross section of the microwave supplier 3. As shown in FIG.

FIG. 17 is a sectional view of a connecting portion (introducing portion) between the microwave supplier 3 and the microwave waveguide 5. As shown in FIG.

FIG. 18 is a view of the H plane provided with the slots 3b of the microwave supplier 3 as viewed from below.

The microwave supply means 3 shown in FIG. 15 is equivalent to a rectangular waveguide bent into a ring shape so that the E surface 3d of the rectangular waveguide becomes a curved surface. Therefore, the two opposing H planes are respectively on the same plane.

The microwave propagating in the TE ₁₀ mode, for example, from the waveguide 5 is distributed in opposite directions by a microwave distributor 10 such as an E-branch block at the connection portion.

The microwave propagating through the endless annular waveguide 3a propagates while being emitted from the slot 3b extending in a direction intersecting the traveling direction MD.

Such a microwave supply means is called an annular waveguide with a flat slot or a multi-slot antenna (PMA).

In the endless annular waveguide 3a, the microwave propagates while attenuating due to energy emission from the slot. Moreover, since the traveling direction is both directions,
The traveling microwaves interfere with each other, and microwaves having a uniform intensity are radiated in the space 9.

The features are summarized below.

High density: Since high-frequency microwaves are used and a surface wave mode with high propagation efficiency is generated, high-density plasma with an electron density of the order of 10 ¹² cm ⁻³ is generated. Therefore, high-speed and highly reactive processing can be performed.

Large diameter uniformity: Microwaves are introduced from many slots at multiple points, the propagation efficiency of surface waves in the dielectric window is high near the dielectric window, and the electric field can be increased without using a magnetic field that is difficult to uniformize. Since a localized plasma is formed near the window, a large-diameter and uniform plasma can be generated. Therefore, uniform processing of a large-area substrate becomes possible.

Low temperature / low potential: microwave absorption, that is, plasma generation is performed near the inner surface of the dielectric window, and the electric field is localized on the window side, and plasma is generated on the substrate side by diffusion. Can be suppressed. Therefore, notch generation during etching, charge-up damage, DUV
Damage is reduced. In addition, since the electron temperature is low, the sheath potential is also kept low, and low-damage processing can be performed.

High confinement: Since the electric field can be localized near the dielectric window, the pressure at which the plasma diffusion is suppressed is reduced to 40P.
Plasma having high confinement can be generated in a high pressure region of a or more. Therefore, highly low-damage processing can be performed.

Capacitively coupled plasma (CCP) has problems such as low electron density, and electron cyclotron resonance (ECR) plasma and helicon wave plasma (HWP) have problems such as high electron temperature and difficulty in uniforming large diameter. The present invention is promising as a next generation plasma source.

In the case of application to an asher, a high-density confined plasma can be generated since the plasma is required to be processed with low damage and high speed that cannot be achieved by contacting the plasma with the substrate. it is conceivable that.

In particular, in the plasma processing apparatus of the present invention, since the gas is emitted toward the H surface, the gas flows to the center via a uniform and thin high-density low-temperature plasma generation region. In this manner, even near the center of the object to be processed, uniform processing can be performed without reducing the processing speed.

Next, another microwave feeder according to a preferred embodiment of the present invention will be described.

FIG. 19 shows a top view (a), a transverse section (b) and a longitudinal section (c) of the microwave supplier 3.

[0211] The microwave supplier 3 has a plurality of annular waveguides 43 and 44 having different diameters.

The large-diameter outer annular waveguide 43 includes an outer wall 49 serving as an E-plane, an inner wall 48 serving as another E-plane,
An upper wall 53 serving as a planar H surface and another planar H surface
And a lower wall 52 serving as a surface. The lower wall 52 is provided with a plurality of slots 36 '.

The small-diameter inner annular waveguide 44 is likewise E-shaped.
The lower wall 52 includes an innermost side wall 47 serving as a surface, the inner wall 48, the upper wall 53, and the lower wall 52.
Is provided with a plurality of slots 36.

Each of the annular waveguides 43 and 44 has the same configuration as the annular waveguide 3a (see FIG. 1 and the like) according to the above-described embodiment, and each has a TE structure as shown in FIG.
It has a rectangular cross section capable of transmitting microwaves in a mode.

Numeral 54 is a microwave introduction port to the outer annular waveguide 43, and more preferably has a rectangular cross section of the same size as the rectangular cross section of the waveguide 43. Reference numeral 55 denotes a microwave introduction port to the inner annular waveguide 44, and more preferably, has a rectangular cross section having the same size as the rectangular cross section of the waveguide 44.
More preferably, it is preferable that each waveguide is not provided with a termination surface and is formed into a non-terminal ring.

In the example shown in FIG. 19, the two waveguides are integrated, but even if the individual annular waveguides are arranged in a concentric manner on a certain support table, as shown in FIG. An assembly including a flat plate and a member having a plurality of annular grooves serving as a waveguide may be used.

When the microwave feeder is formed as an assembly, a slotted flat plate for the outer annular waveguide 43 and a slotted flat plate for the inner annular waveguide 44 can be formed separately. And like the embodiment of FIG. 5 described above,
By preparing a large number of slotted flat plates with different shapes, numbers, sizes, distributions, etc., and making them interchangeable, it is possible to easily produce a microwave supplier suitable for the desired microwave radiation intensity distribution. it can.

The shape of each of the annular waveguides 43 and 44 is not limited to a circle as shown in FIG. 19, and may be a square as in the embodiment of FIG. It may be a star shape or the like.

The outer annular waveguide 43 and the inner annular waveguide 44
May be the same or different from each other in the shape, number, size, and distribution of the slots provided in each of them. Except for special plasma processing applications, the inner waveguide 4
4, the number of slots 3b of the outer waveguide 43
If the number is smaller than b ', the device design becomes easier.

In order to simplify the apparatus configuration and use only one microwave power source, electromagnetic wave distribution and introduction means should be formed near the microwave introduction ports 54 and 55 of the microwave supply device 3 and microwave distribution should be performed. It is preferable to provide an H-branch for determining the ratio.

Microwaves are introduced into the microwave introduction ports 55 and 56, for example, in a TE _no mode.

The microwaves introduced into the annular waveguides 43 and 44 are distributed by the distributor 10 in opposite directions.
Waveguide 43 in clockwise or counterclockwise TE _no mode,
44, respectively.

During propagation, microwaves are radiated outside from slots 3b and 3b 'provided on the H plane.

The microwaves traveling in opposite directions interfere with each other in the waveguides 43 and 44, and in some cases, generate a standing wave, and the radiation intensity of the microwave from the slot is stabilized.

As described above, according to the microwave supply device of the present invention, microwaves having a relatively large intensity in a relatively large area can be radiated in a substantially planar manner.

Here, with reference to FIGS. 20 to 23, an assembly type microwave supplier, electromagnetic wave distribution and introduction means,
A plasma processing apparatus using them will be described in detail.

In FIG. 20, reference numeral 1 denotes a container for forming the plasma generation chamber 9. 4 is a dielectric window, 3 is a multiple annular waveguide with a flat slot as a microwave supplier for supplying microwaves to the plasma generation chamber 9, and 57 is a microwave introducing into the endless annular waveguide 3. Waveguide 57 for
W is an object to be processed, 2 is holding means for the object to be processed W, 7 is a processing gas supply means, and 8 is an exhaust port.

[0228] The microwave supply device is a grooved first conductive member 3.
2 and a second conductive member 31 formed of a flat plate with slots 3b and 3b 'as shown in FIG.

In the vicinity of the microwave introduction ports 54 and 55, a distributor 56 for determining a distribution ratio of microwaves to the waveguides 43 and 44 is provided. In the apparatus shown in FIG. 20, the electromagnetic wave distribution introducing means is a waveguide 5 having a branch path.
7 and a distributor 56 such as an H branch.

FIG. 20 shows an example in which the distributor 56 is formed of a conductor having a triangular cross section having at least two distribution surfaces.
However, the present invention is not limited to this, and may be a plate-shaped member.

[0231] The distributor can also be configured to make the distribution ratio variable.

FIG. 22 shows an example of an H-branch with a distributor to each of the waveguides 43 and 44 used in the present invention. Reference numeral 61 denotes a plate-shaped or triangular prism-shaped movable distribution block 56 provided at the center of the T-shaped branch. Reference numeral 62 denotes a rotatable movable part of the Y-shaped branch. Reference numeral 63 denotes a rotatable movable portion of the modified Y-shaped branch, and reference numeral 64 denotes a type in which the other portion expands and contracts.

The distributor 56 has a small reflection of the microwave in the incident direction and has a distribution ratio of one to the other of at least 0.2 to 0.5, more preferably 0.0 to 0.6.
If it can be adjusted up to, it is applicable. Distributor 56
In the case of a type that expands and contracts, for example, by using a screw and adjusting the height of the screw by adjusting the pushing amount of the screw, a distributor that can easily expand and contract can be realized with a variable distribution ratio.

As an example, FIG. 23 shows the relationship between the tilt angle and the microwave intensity in the tilt type in which the movable part rotates. The distribution ratio could be changed from about 0.9 to about 3.5 on the outer side, assuming that the inner side is 1. Of course, when it is desired to change the distribution ratio, the length or rotation angle of the distribution block or the shape of the triangular prism may be appropriately changed.

The H-branch having a mechanism for adjusting the distribution ratio of electromagnetic waves is used not only in the plasma processing apparatus but also in other cases where the distribution ratio of electromagnetic waves needs to be adjusted. On the other hand, E in the annular waveguides 43 and 44
The branching device 10 can be omitted.

The materials constituting the H-branch unit, the E-branch unit, and the multiple annular waveguide of the present invention described above are the same as those of the single annular waveguide described above. Although it is possible, and in order to minimize the propagation loss of the microwave, a high conductivity such as Al,
Optimum is Cu, Ag / Cu-plated stainless steel, or the like. The direction of the introduction port to the multiple endless annular waveguide used in the present invention is parallel to the H plane from the tangential direction as long as the microwave can be efficiently introduced into the microwave propagation space in the multiple annular waveguide. It may be introduced, or it may be introduced perpendicularly to the H plane and divided into two inside and outside waveguides near the introduction port.

The shape of the slot provided in each waveguide of the multiple annular waveguide used in the present invention is the same as the slot shape of the single annular waveguide described above, and has a length perpendicular to the microwave propagation direction. May be rectangular, elliptical, S-shaped, cross-shaped or array-shaped, as long as is equal to or more than １ ／ of the guide wavelength.

The slot spacing and slot size of the multiple annular waveguide used in the present invention are selected and designed in the same manner as in the case of the single annular waveguide described above.

The rectangular cross sections of the respective annular waveguides may have mutually different areas, but the cross sections perpendicular to the traveling direction of the microwaves have the same rectangular cross section so that microwaves of the same mode can propagate. It is desirable to choose a wave path.

It is desirable that the radiation intensity of the microwave is adjusted by the slot arrangement density or the like.

According to the microwave supply device of the present embodiment and the plasma processing apparatus using the same, a multiple annular waveguide in which a plurality of annular waveguides having different sizes are concentrically arranged and a slot is provided in a plane portion thereof. By using a wave tube, the diameter 30
A large-area plasma suitable for processing a 0-mm wafer or a large-area substrate equal to or larger than the wafer can be generated. This makes it possible to perform high-quality processing at a lower temperature more uniformly.

In particular, when a plurality of waveguides are arranged so that the H-plane of the annular waveguide is on the same plane, high-density low-potential plasma is efficiently generated uniformly even under a high-pressure condition and a large-area substrate. I can make it. Such effects can be achieved without using a magnetic field.

(Sixth Plasma Processing Apparatus) A plasma processing apparatus using a multiple endless waveguide as a microwave supply means of the present invention will be described with reference to FIG.

Reference numeral 1 denotes a plasma processing chamber, 4 denotes a dielectric separating the plasma generation chamber 9 from the atmosphere side, 3 denotes a multiple endless annular waveguide for introducing a microwave into the plasma processing chamber 101, and 56 denotes a multi-endless waveguide. An H-branch with a distribution ratio adjusting mechanism for distributing and introducing microwaves to the terminal annular waveguide 3; 43 and 44 are waveguides which are microwave propagation spaces through which microwaves propagate;
3b, 3b 'are slots for supplying microwaves from the multiple endless annular waveguide 3 into the plasma generation chamber 9, W is the object to be processed, 2 is a holding means, 114 is a heater for heating the object to be processed W, 7 Denotes a processing gas supply means, and 8 denotes an exhaust port. It is more preferable that the gas outlet 7a is directed to the H plane.

Generation and processing of plasma are performed as follows. The target object W is set on the holding means 2 and the target object W is heated to a desired temperature using the heater 114 as necessary. The inside of the plasma generation chamber 9 is evacuated via an exhaust system (not shown).

Subsequently, the plasma processing gas is discharged into the plasma generation chamber 9 at a predetermined flow rate through the processing gas discharge port 7a. Next, the conductance valve (not shown) provided in the exhaust system (not shown) is adjusted, and the plasma generation chamber 9 is adjusted.
Is maintained at a predetermined pressure. Desired power from the microwave power supply 6 is introduced into the annular waveguides 43 and 44 from the H-branch 56 with the distribution ratio adjusting mechanism. The introduced microwave is split into two by the H-branch 56, and the waveguide 4 is a propagation space.
It propagates several times clockwise and counterclockwise in 3, 44.

The microwaves divided into two interfere with each other, for example, strengthen the electric field crossing the slots 3b, 3b 'provided for every half of the guide wavelength, and pass through the dielectric window 4 through the slots 3b, 3b'. It is supplied to the plasma generation chamber 9. Electrons are accelerated by the electric field of the microwave supplied into the plasma generation chamber 9, and plasma is generated in the plasma generation chamber 9.
At this time, the processing gas is excited by the generated high-density plasma, and processes the surface of the processing target W placed on the holding unit 2.

For example, the dielectric window 4 is made of synthetic quartz having a diameter of 299 mm and a thickness of 12 mm. The endless annular waveguides 3b and 3b 'have a cross section of 27 mm x 96 mm in the inner wall perpendicular to the direction in which the microwave travels, and the center diameter of the inner annular waveguide 44 is 152 mm (perimeter 3).
λg), and the center diameter of the outer annular waveguide 43 is 354 mm (perimeter 7λg). Multiple endless annular waveguide members 31, 3
As for the material of No. 2, A1 is used as a conductor in order to suppress the propagation loss of the microwave.

The member 31 constituting the H-plane of the multiple endless annular waveguide 3 has a slot for supplying microwaves to the plasma generation chamber 9. One slot shape is a rectangle having a length of 45 mm and a width of 4 mm, and is formed radially at a half interval of the guide wavelength. The guide wavelength depends on the frequency of the microwave used and the size of the cross section of the waveguide, and when the microwave having the frequency of 2.45 GHz and the waveguide having the above dimensions are used, about 159 mm is used. Becomes

FIG. 20 shows the structure of the multiple endless annular waveguide 3 shown in FIG.
As shown in FIG. 1, six slots are formed in the inner waveguide and 14 slots are formed in the outer waveguide at intervals of about 79.5 mm. A microwave power supply 6 having a frequency of 2.45 GHz and having a 4E tuner, a directional coupler, and an isolator is connected to the multiple endless annular waveguide 3 in this order.

Using the microwave plasma processing apparatus shown in FIG. 20, an Ar flow rate of 500 sccm and a pressure of 10 mT
Plasma was generated under the conditions of orr, 1 Torr, and microwave power of 1.5 kW, and the obtained plasma was measured.

The plasma measurement was performed by the single probe method as follows. The voltage applied to the probe was changed in the range of -50 to +100 V, and the current flowing through the probe was measured by an IV measuring instrument.
The electron density, electron temperature, and plasma potential were calculated from the curves by the method of Langmuir et al.

As a result, the electron density was 1.1 × 10 ¹² / cm ³ ± 2.7% at 10 mTorr (within φ300 plane) and 5.7 × 10 ¹¹ / cm ³ ± 4 at 1 Torr.
It was 2% (within φ300 plane), and it was confirmed that high-density and uniform plasma was formed in the large-diameter space.

(Seventh Plasma Processing Apparatus) FIG. 24 shows a plasma processing apparatus of a system in which microwaves are tangentially introduced into one of the multiple annular waveguides 143 and introduced into the other 144 toward the distributor 110.

Reference numeral 101 denotes a vacuum vessel having an internal plasma generation chamber 109, and reference numeral 102 denotes holding means for mounting and holding the object W to be processed, and has a heater 114 as required.

Numeral 103 denotes a microwave supply means. Here, a plurality of annular waveguides 143 and 144 are provided as in the example of FIG.
And a multiple endless annular waveguide having slots 103b and 103b 'in the H plane. Microwaves from the microwave power supply 6 pass through the waveguides 103b 'and 103 from the tangential inlet 105b and the normal inlet 105a, respectively.
3b.

The microwaves are transmitted through the slots 103b, 103
b ′ is radiated into the chamber 109 through the dielectric window 104. The method of plasma processing by this apparatus is as follows. The object W is placed on the holding means 102 and heated to a predetermined temperature by the heater 114.

On the other hand, the inside of the container 101 is evacuated using the exhaust system (24, 25, 26). Subsequently, the gas supply system (21,
22 and 23), when a gas is introduced into the supply means 107 at a predetermined flow rate, the gas is released from the gas discharge port 107a. It is more preferable that the direction of the gas outlet 107a is directed to the H plane.

Next, the conductance control valve 26 of the exhaust system (24, 25, 26) is adjusted to maintain the inside of the chamber 109 at a predetermined pressure.

A desired electric power is introduced from the microwave power supply 6 into the multiple endless annular waveguide 103. The introduced microwaves pass through the dielectric windows 104 via slots 103b and 103b 'formed every 1/2 or 1/4 of the guide wavelength.
And is introduced into the plasma generation chamber 109. The microwave propagated one round without being emitted from the slot after being introduced tangentially interferes and strengthens with the newly introduced microwave, and most of the microwave is emitted into the plasma generation chamber 109 until it propagates several times. Is done.

The electrons are accelerated by the electric field of the microwave introduced into the plasma generation chamber 109, and
In 09, plasma is generated. At this time, the processing gas is excited by the generated high-density plasma, and the holding means 102
The surface of the object to be processed W placed thereon is processed.

The shape, size and material of the dielectric window 104 are the same as those of the dielectric window 4 in FIG.

The shapes and dimensions of the waveguides 143 and 144, the shapes and dimensions of the slots 103b and 103b ', the arrangement density, and the like are the same as those of the corresponding parts in FIG.

Using the microwave plasma processing apparatus shown in FIG. 24, the Ar flow rate was 500 sccm, and the pressure was 10 mT.
Plasma was generated under the conditions of orr, 1 Torr, and microwave power of 1.5 kW, and the obtained plasma was measured. The plasma measurement was performed by the single probe method as follows. Apply a voltage of -50 to the probe.
The current flowing through the probe was measured by an IV measuring instrument, and the electron density, electron temperature, and plasma potential were calculated from the obtained IV curve by the method of Langmuir et al.

As a result, the electron density was 1.3 × 10 ¹² / cm ³ ± 3.3% (within φ300 plane) at 10 mTorr and 6.2 × 10 ¹¹ / cm ³ ± 4 at 1 Torr.
It was 6% (within φ300 plane), and it was confirmed that high-density and uniform plasma was formed in the large-diameter space.

(Eighth Plasma Processing Apparatus) The plasma processing apparatus shown in FIG. 25 is provided with a bias applying mechanism 302 for applying an RF bias to the holding means 102 of the plasma processing apparatus shown in FIG.

Generation and processing of plasma are performed as follows. The workpiece W is placed on the holding means 102 and heated to a desired temperature using the heater 114. Exhaust system (2
The inside of the plasma generation chamber 109 is evacuated via (4, 25, 26).

Subsequently, the plasma processing gas is supplied at a predetermined flow rate through the processing gas discharge port 107a into the plasma generation chamber 1.
Release in 09. It is more preferable that the direction of the gas outlet 107a is directed to the H plane.

Next, the conductance control valve 26 provided in the exhaust system (24, 25, 26) is adjusted to maintain the inside of the plasma generation chamber 109 at a predetermined pressure. RF power is supplied to the holding means 102 using the RF bias applying means 302, and desired power is supplied from the microwave power supply 6 to the H-branch 56 with a distribution ratio adjusting mechanism from the waveguide 57. The distributed microwave is applied to each waveguide 1
43, 144, and slots 103b, 103
b 'through the dielectric 302 and the plasma generation chamber 109
Supplied to Electrons are accelerated by the electric field of the microwave introduced into the plasma generation chamber 109, and plasma is generated in the chamber.

At this time, the processing gas is excited by the generated high-density plasma, and processes the surface of the workpiece W placed on the holding means 102. Further, the kinetic energy of ions incident on the substrate can be controlled by the RF bias.

(Ninth Plasma Processing Apparatus) In the plasma processing apparatus of FIG. 26, a cooler 414 as cooling means is provided in the plasma processing apparatus of FIG.

The generation and processing of plasma are performed as follows. The object W is placed on the holding means 102 and cooled using the cooler 414. Exhaust system (24, 25,
The inside of the plasma generation chamber 109 is evacuated via 26).

Subsequently, the plasma processing gas is supplied at a predetermined flow rate through the processing gas discharge port 107a into the plasma generation chamber 1.
Release in 09.

Next, the conductance control valve 26 provided in the exhaust system (24, 25, 26) is adjusted to
9 is maintained at a predetermined pressure. RF bias applying means 3
02, RF power is supplied to the holding means 102, and desired power is supplied from the microwave power supply 6 to the H-branch unit 56 with the distribution ratio adjusting mechanism and the slots 103b and 103b 'of the multiple endless annular waveguide 103. The plasma is supplied to the plasma generation chamber 109 through the dielectric window 104. Electrons are accelerated by the electric field of the microwave introduced into the plasma generation chamber 109, and plasma is generated in the chamber.

At this time, the processing gas is excited by the generated high-density plasma, and is held by the holding means 10 with the cooler 414.
The surface of the object to be processed W, which is placed on the substrate 2 and whose temperature rise is suppressed, is processed.

Also, the kinetic energy of ions incident on the substrate can be controlled by the RF bias. Further, by using the cooler 414, overheating of the substrate due to ion incidence, which is a problem when high-density plasma and high bias are used, can be suppressed.

(Plasma Processing Apparatus in FIG. 10) The plasma processing apparatus in FIG. 27 has a microwave supplier 103 in which two endless annular waveguides 43 and 44 are concentrically arranged, similarly to the above-described apparatus. ing.

The microwave supplier 103 is an assembly of a grooved conductive member 32 and a plate-shaped conductive member 31 having slots 103b and 103b '.

[0279] In the vicinity of the microwave introduction port, an H branch 56
Are provided and the installation angle is arranged so as to be adjustable.

The microwave introduced from the waveguide 57 is H
The light is distributed and introduced into the inner waveguide 44 and the outer waveguide 43 by the branching device 56.

In each of the waveguides 43 and 44, the microwave is distributed in the clockwise direction and the counterclockwise direction by the distributor 110, and propagates through the endless waveguides 43 and 44 to interfere with each other. The microwave introduced into each of the waveguides 43 and 44 is supplied from the slots 103b and 103b 'through the dielectric window 104 into the plasma generation chamber / plasma processing chamber 109 in the container 101. Then, the annular waveguide 43,
Propagating through the inside 44 for two or three rounds, respectively, attenuates so that plasma cannot be generated. The gas supply means 10 is provided in the chamber 109.
Seven gas outlets 107a are provided.

Gas is discharged from the gas discharge port 107a at the end of the gas discharge path directed obliquely upward toward the dielectric window 104 and the H surface of each of the waveguides 43 and 44.

[0283] The discharge port 1 is placed on the inner wall around the container 101.
Since a plurality of 07a are provided diagonally, the gas is discharged toward the center of the chamber 109 via the plasma region P. The structure of the gas outlet 107a can be selected and designed in the same manner as in the embodiment shown in FIGS. 1, 2, 6, and 9.

Reference numeral 7P denotes a purge gas supply means. The discharge port at the end of the gas discharge path which is directed obliquely upward is a dielectric window 104.
Is aimed at. The purge gas supply means 7P includes nitrogen,
It is connected to a supply system (27 to 29) for a purge gas such as argon, and the purge gas in the cylinder 27 is supplied to the room via a valve 28 and a mass flow controller 29.

The processing using the apparatus shown in FIG. 27 is as follows.

First, the holding means 102 is lowered to open the container.

The target object W is placed on the place where the lift pins 102a are raised.

By lowering the lift pins 102a, the workpiece W is placed immediately above the holding means 102, the holding means 102 is raised, and the container is closed.

By operating the vacuum pump 24,
The inside of the container is further evacuated to reduce the pressure.

The processing gas is supplied from the gas supply system (21 to 23) into the container at a predetermined flow rate. In this manner, the processing gas is released from the plurality of gas discharge ports 107a toward the H surface having the slots.

The microwave power supply 6 is operated to supply microwaves to the microwave supplier 103. At this time, the microwave is supplied in the TE ₁₀ mode, and the power is supplied to each waveguide 4.
A value such as 1.0 k that can propagate 2, 3 rounds of 3, 44
W or more.

Since this value depends on the circumference of the waveguide, the size of the slot, and the like, it is not limited to this value.

The microwaves radiated from the slots 103b and 103b 'are supplied to the space 109 between the plasma generating chambers in the container 101 through the dielectric window to turn the processing gas into plasma.

The object to be processed W is processed using the radicals, ions and electrons of the plasma.

When the processing is completed, a purge gas is introduced,
Increase the pressure in the vessel to atmospheric pressure.

The holding means 102 is lowered to open the container,
The workpiece W is taken out by raising the lift pins 102a.

[0297]

EXAMPLES Hereinafter, the microwave plasma processing apparatus and the processing method of the present invention will be described more specifically with reference to examples.
The present invention is not limited to these examples.

Reference Example 1 Photoresist ashing was performed using the microwave plasma processing apparatus shown in FIG.

As the object to be processed W, an 8-inch silicon wafer immediately after a via hole was formed by etching an interlayer insulating film exposed from a photoresist pattern was used. First, after the Si wafer is set on the holding means 102, the plasma generation chamber 10 is set via the exhaust system (24 to 26).
The inside of 9 was evacuated, and the pressure was reduced to 10 ^-5 Torr. Oxygen gas is supplied through the plasma processing gas supply means 107.
It was introduced into the room at a flow rate of slm. Then, the exhaust system (24
26), the inside of the generation chamber 109 was maintained at 2 Torr. A microwave power of 2.45 GHz 1.5 kW from the microwave power source 6 is applied to the annular waveguide 103 with a flat slot in TE ₁₀ mode.
Was introduced. Thus, the microwave was radiated from the slot 103b to generate plasma in the chamber 109. At this time, the oxygen gas introduced through the plasma processing gas supply port 107 is excited, decomposed and reacted in the plasma generation chamber 109 to become ozone, transported in the direction of the Si wafer W, and
The photoresist on the surface of the i-wafer was oxidized, and the oxidized photoresist was vaporized and removed. After such ashing,
The ashing speed and the substrate surface charge density were evaluated.

The ashing speed obtained was 8.6 μm /
min ± 8.5%, and the surface charge density is −
The value was a sufficiently low value of 1.3 × 10 ¹¹ / cm ² .

Reference Example 2 Photoresist ashing was performed using the microwave plasma processing apparatus shown in FIG.

As an object to be processed W, an 8-inch silicon wafer immediately after a via hole was formed by etching an interlayer insulating film exposed from a photoresist pattern was used. First, after setting the Si wafer on the holding means 102,
The inside of the plasma generation chamber 109 was evacuated through the exhaust system (24 to 26) to reduce the pressure to 10 ^-5 Torr. 2 sl of oxygen gas was supplied through the plasma processing gas supply means 107.
m into the room. Then, the exhaust system (24-2
6) adjust the conductance valve 26 provided in
The room was kept at 2 Torr. A microwave power of 2.45 GHz and 1.5 kW from the microwave power supply 6 was tangentially introduced into the annular waveguide 103 having a slot with a flat plate. Thus, microwaves were radiated from the slots to generate plasma in the plasma generation chamber 109. At this time, the oxygen gas introduced through the plasma processing gas supply port 107 is excited, decomposed and reacted in the plasma generation chamber 109 to become ozone, transported in the direction of the Si wafer W, and removes the photoresist on the surface of the Si wafer. The oxidized and oxidized photoresist was vaporized and removed. After such ashing, the ashing speed and the substrate surface charge density were evaluated.

The obtained ashing speed was 8.9 μm /
min ± 9.4% is extremely large, and the surface charge density is also −
It was a sufficiently low value of 1.4 × 10 ¹¹ / cm ² .

Reference Example 3 Using the microwave plasma processing apparatus shown in FIG. 11, a silicon nitride film for protecting a semiconductor element was formed.

As the object to be processed W, a P-type single-crystal silicon substrate with an interlayer insulating film on which a line and space Al wiring pattern having a width of 0.5 μm and a pitch of 0.5 μm is formed (plane orientation <100>, resistivity 10 Ωcm). First, after the silicon substrate W is set on the holding means 102, the plasma generation chamber 1 is set via the exhaust system (24 to 26).
09 was evacuated and evacuated to a value of 10 ^-7 Torr. Subsequently, a current is supplied to the heater 114 so that the silicon substrate W
The substrate was heated to 00 ° C. and kept at this temperature. Nitrogen gas is supplied through the plasma processing gas supply
At a flow rate of sccm, monosilane gas is supplied at 200 sc
cm into the room. Then, the exhaust system (24 ~
The conductance valve 26 provided in 26) was adjusted to maintain the room at 20 mTorr. Then, a microwave power of 2.45 GHz 3.0 kW from the microwave power source 6 is supplied to the annular waveguide 10 with a flat slot in the TM ₁₀ mode.
3 was introduced. Thus, plasma was generated in the plasma generation chamber 109. At this time, the nitrogen gas supplied through the plasma processing gas supply port 107 is excited and decomposed into an active species in the plasma generation chamber 109, is transported in the direction of the silicon substrate W, reacts with the monosilane gas, and reacts with the silicon nitride. The film was formed on the silicon substrate W with a thickness of 1.0 μm. After the film formation, film quality such as film formation speed and stress was evaluated. The stress was determined by measuring the change in the amount of warpage of the substrate before and after film formation using a laser interferometer Zygo (trade name).

The rate of film formation of the obtained silicon nitride film is 5
Extremely large at 40 nm / min, and the film quality is stress 1.1 ×
10⁹ dyne / cm^Two (Compression), leak current 1.2 ×
10 ^-Ten A / cm^Two , Very good withstand voltage 9MV / cm
It was confirmed that the film was a quality film.

Reference Example 4 Using the microwave plasma processing apparatus shown in FIG. 12, a silicon oxide film and a silicon nitride film for preventing reflection of a plastic lens were formed.

As the object to be processed, a plastic convex lens having a diameter of 50 mm was used. After placing the lens on the holding means 102, the inside of the plasma generation chamber 109 was evacuated via the exhaust system (24 to 26) to reduce the pressure to 10 ^-7 Torr. Nitrogen gas was introduced into the room at a flow rate of 150 sccm, and monosilane gas was introduced at a flow rate of 100 sccm via the plasma processing gas supply means 107. Next, the conductance valve 26 provided in the exhaust system (24 to 26) was adjusted to maintain the room at 5 mTorr.
Then, 2.45 GHz, 3.0 k from microwave power supply 6
W microwave power is applied to the annular waveguide 10
3 was tangentially introduced.

[0309] Thus, the microwave was radiated from the slot to generate plasma in the room. At this time, the nitrogen gas supplied through the plasma processing gas supply port 107 is
Excited and decomposed indoors to become active species such as nitrogen atoms,
It is transported in the direction of the lens W and reacts with monosilane gas,
A silicon nitride film was formed on the lens W with a thickness of 21 nm.

Next, plasma processing gas supply means 107
, Oxygen gas was introduced into the room at a flow rate of 200 sccm, and monosilane gas was introduced into the room at a flow rate of 100 sccm. Next, the conductance control valve 26 provided in the exhaust system (24 to 26) is adjusted, and the room is adjusted to 1 mTorr.
Held. Next, a microwave power of 2.45 GHz and 2.0 kW was tangentially introduced from a microwave power supply (not shown) into the annular waveguide 103 having a flat slot. Thus, plasma was generated in the plasma generation chamber. At this time, the oxygen gas supplied via the plasma processing gas supply port 107 is excited and decomposed in the plasma generation chamber 109 to become active species such as oxygen atoms, is transported in the direction of the lens, and reacts with the monosilane gas. A silicon oxide film was formed on the lens with a thickness of 86 nm. After the film formation, the film formation speed and the reflection characteristics were evaluated.

[0311] The film formation rates of the obtained silicon nitride film and silicon oxide film were 300 nm / min and 360 n, respectively.
m / min, and the film quality was confirmed to be very good optical characteristics, with a reflectivity at around 500 nm of 0.3%.

Reference Example 5 A silicon oxide film for interlayer insulation of a semiconductor element was formed using the microwave plasma processing apparatus shown in FIG.

The object to be processed has a width of 0.5 μm at the top.
A P-type single-crystal silicon substrate (plane orientation <100>, resistivity 10 Ωcm) on which a line and space A1 pattern having a pitch of 0.5 μm was formed. First, the silicon substrate W was set on the holding means 102. The inside of the plasma generation chamber 109 was evacuated via the exhaust system (24 to 26) to reduce the pressure to a value of 10 ^-7 Torr. Subsequently, electricity was supplied to the heater 114 to heat the silicon substrate to 300 ° C., and the substrate was kept at this temperature. Oxygen gas was introduced into the room at a flow rate of 500 sccm, and monosilane gas was introduced at a flow rate of 200 sccm via the plasma processing gas supply means 107. Next, the conductance control valve 26 provided in the exhaust system (24 to 26) was adjusted to maintain the inside of the plasma generation chamber 301 at 30 mTorr. Next, while applying a high frequency power of 13.56 MHz and 300 W to the holding means 102, the microwave power supply 2.4.
5 GHz, was introduced in the TM ₁₀ mode microwave power of 2.0kW to flat slotted annular waveguide 103. Thus, microwaves were radiated from the slots to generate plasma in the plasma generation chamber 109. Oxygen gas supplied through the plasma processing gas supply port 107 is excited and decomposed into active species in the room, is transported in the direction of the silicon substrate, reacts with the monosilane gas, and the silicon oxide film is deposited on the silicon substrate W. It was formed with a thickness of 0.8 μm. At this time, the ion species are accelerated by the RF bias and are incident on the substrate to cut the film on the pattern to improve the flatness, thereby producing an effect. After the treatment, the film formation rate, uniformity, dielectric strength, and step coverage were evaluated. The step coverage was evaluated by observing a cross section of the silicon oxide film formed on the Al wiring pattern with a scanning electron microscope (SEM) and observing voids.

The film formation rate and uniformity of the obtained silicon oxide film are as good as 240 nm / min ± 2.5%, the film quality is 8.5 MV / cm in dielectric strength, and the film is void-free and of good quality. Was confirmed.

Reference Example 6 The microwave plasma processing apparatus shown in FIG. 14 was used to etch an insulating film between layers of a semiconductor element.

The object to be processed has a width of 0.35 μm and a thickness of 0.35 μm.
P-type single crystal silicon substrate having a 1 μm thick silicon oxide film formed on a 35 μm pitch line-and-space Al pattern (plane orientation <100>, resistivity 10 Ωcm)
It was used. First, after the silicon substrate was set on the holding means 102, the inside of the plasma generation chamber 109 was evacuated via the exhaust system (24 to 26) to reduce the pressure to a value of 10 ^-7 Torr. CF ₄ was introduced into the plasma generation chamber at a flow rate of 300 sccm via the plasma processing gas supply means 107. Next, the conductance control valve 26 provided in the exhaust system (24 to 26) was adjusted to maintain the inside of the plasma generation chamber 109 at a pressure of 5 mTorr. Then 1
A high frequency power of 3.56 MHz 300 W is applied to the holding means, and a microwave power source 6 supplies 2.45 GHz.
Microwave power of 2.0kW was introduced in TM ₁₀ mode in the flat slotted annular waveguide 203. Thus, microwaves are radiated from the slots and the plasma generation chamber 109
A plasma was generated inside. The CF ₄ gas supplied through the plasma processing gas supply port 107 is excited and decomposed into an active species in the plasma generation chamber 109, is transported in the direction of the silicon substrate W, and is oxidized by ions accelerated by a self-bias. The silicon film has been etched.
The cooler 414 did not raise the substrate temperature beyond 90 ° C. After the etching, the etching rate, the selectivity, and the etching shape were evaluated. The etched shape was evaluated by observing the cross section of the etched silicon oxide film with a scanning electron microscope (SEM).

The etching rate was as good as 600 nm / min and the selectivity to polysilicon was 20. The etching shape was almost vertical, and it was confirmed that the microloading effect was small.

Reference Example 7 A polysilicon film for a gate electrode of a semiconductor element was etched using the microwave plasma processing apparatus shown in FIG.

As the object to be processed, a P-type single crystal silicon substrate having a polysilicon film formed on the uppermost portion (plane orientation <10
0>, resistivity 10 Ωcm). First, after the silicon substrate is set on the holding means 102, the exhaust system (24 to
The inside of the plasma generation chamber 109 is evacuated via 26),
The pressure was reduced to a value of 10 ^-7 Torr. The CF ₄ gas is supplied at 300 scc via the plasma processing gas supply means 107.
m and oxygen at a flow rate of 20 sccm.
Introduced within. Next, the conductance control valve 26 provided in the exhaust system (24 to 26) was adjusted to maintain the inside of the plasma generation chamber 109 at a pressure of 2 mTorr. Then, the holding means 1 holds the high frequency power of 400 kHz and 300 W.
It is applied with 02, introduced in TM ₁₀ mode microwave power 2.45GHz1.5kW in tabular slotted annular waveguide 203. Thus, microwaves were radiated from the slots to generate plasma in the plasma generation chamber 109. The CF ₄ gas and oxygen supplied through the plasma processing gas supply port 107 are supplied to the plasma generation chamber 40.
1, is excited and decomposed into active species, and the silicon substrate W
And the polysilicon film was etched by ions accelerated by the self-bias. Cooler 4
According to No. 14, the substrate temperature did not rise above 80 ° C. After the etching, the etching rate, the selectivity, and the etching shape were evaluated. The etched shape was evaluated by observing the cross section of the etched polysilicon film with a scanning electron microscope (SEM).

The etching rate was 800 nm / min and the selectivity to SiO ₂ was as good as 30. The etching shape was vertical, and it was confirmed that the microloading was small.

Reference Example 8 Photoresist ashing using plasma was performed in the same manner as in Example 1 using the plasma processing apparatus shown in FIG. As a result, uniform and residue-free ashing was performed in a short time.

(Example 1) Ashing of photoresist was performed using the microwave plasma processing apparatus shown in FIG.

As the object to be processed W, a silicon wafer (300 mm wafer) immediately after forming a via hole by etching the SiO ₂ film exposed from the photoresist pattern
It was used.

First, after the Si wafer is set on the holding means 2, the room is evacuated via an exhaust system (not shown) to
The pressure was reduced to 0 ^-5 Torr. Oxygen gas was introduced into the room at a flow rate of 2 slm through the plasma processing gas supply means 7.

Next, the conductance control valve (not shown) provided in the exhaust system (not shown) was adjusted to
Torr.

In a room, power of 2.0 kW from a microwave power supply of 2.45 GHz is not multiplexed by using an H splitter 56 adjusted so that the distribution ratio becomes 0.5 inside / 0.5 outside. It was supplied via a terminating annular waveguide 3.

[0327] Thus, plasma was generated in the room.
At this time, the supplied oxygen gas was excited, decomposed and reacted in the plasma generation chamber 9 to become ozone, transported in the direction of the silicon wafer, oxidized the photoresist on the wafer, and was vaporized and removed. After the ashing, the ashing speed and the substrate surface charge density were evaluated.

The resulting ashing speed was 8.2 μm /
min ± 7.2% is extremely large, and the surface charge density is also 1.
This was a sufficiently low value of 3 × 10 ¹¹ / cm ² .

Example 2 Ashing of photoresist was performed using the microwave plasma processing apparatus shown in FIG.

The same object as in Example 1 was used as the object to be processed.

First, after the Si wafer was set on the holding means 102, the plasma processing chamber was evacuated via the exhaust system (24 to 26) to reduce the pressure to 10 ^-5 Torr. Oxygen gas is supplied through the plasma processing gas discharge port 107a.
It was introduced into the plasma processing chamber at a flow rate of slm.

Next, the valve 26 provided in the exhaust system (24 to 26) was adjusted to maintain the inside of the processing chamber at 2 Torr. 2.0 kW of power was supplied from a microwave power supply of 2.45 GHz into the plasma processing chamber through the multiple endless annular waveguide 103 whose distribution ratio was adjusted to 0.6 inside / 0.4 outside. Thus, plasma was generated in the plasma processing chamber. At this time, the plasma processing gas discharge port 10
Oxygen gas released via 7a was excited, decomposed and reacted in the plasma processing chamber to become ozone, transported in the direction of the silicon wafer, oxidized the photoresist on the silicon wafer, and was vaporized and removed. After the ashing, the ashing speed and the substrate surface charge density were evaluated.

The ashing speed obtained was 8.6 μm /
min ± 7.8% is extremely large, and the surface charge density is also 1.
The value was a sufficiently low value of 2 × 10 ¹¹ / cm ² .

Example 3 Using the microwave plasma processing apparatus shown in FIG. 20, a silicon nitride film for protecting a semiconductor element was formed.

As the object to be processed, the width of Al was 0.5 μm,
P-type single crystal silicon wafer of about 300 mm diameter with an interlayer insulating film on which a line and space pattern with a pitch of 0.5 μm is formed (plane orientation <100>, resistivity 10Ωc)
m) was used.

First, after the silicon wafer was set on the holding means 2, the plasma processing chamber was evacuated via an exhaust system (not shown) to reduce the pressure to 10 ^-7 Torr. Subsequently, a current is supplied to the heater 114 so that the silicon wafer is
C. and the substrate was kept at this temperature. Nitrogen gas was introduced into the processing chamber at a flow rate of 600 sccm, and monosilane gas was introduced at a flow rate of 200 sccm through the plasma processing gas discharge port 7a.

Next, the conductance control valve (not shown) provided in the exhaust system (not shown) was adjusted to maintain the inside of the processing chamber at 20 mTorr.

Next, power of 3.0 kW was supplied from a microwave power supply (not shown) of 2.45 GHz, and the distribution ratio was set to be 0.
It was fed through a multiple endless annular waveguide 3 adjusted to 45 / outer 0.55.

[0339] Thus, plasma was generated in the plasma processing chamber. At this time, the nitrogen gas introduced through the plasma processing gas discharge port 7a is excited in the plasma processing chamber,
It was decomposed into active species, transported in the direction of the silicon wafer, reacted with the monosilane gas, and formed a silicon nitride film with a thickness of 1.0 μm on the silicon wafer. After film formation,
The film quality such as film formation speed and stress was evaluated. The stress is obtained by measuring the change in the amount of warpage of the substrate before and after film formation using a laser interferometer Zygo.
(Trade name).

The film formation rate of the obtained silicon nitride film is 5
Extremely large at 40 nm / min, and the film quality is stress 1.1 ×
10⁹ dyne / cm^Two (Compression), leak power 1.3x
10 ^-Ten A / cm^Two , Withstand voltage of 9.7MV / cm
It was confirmed that the film was of good quality.

Example 4 Using the microwave plasma processing apparatus shown in FIG. 24, a silicon oxide film and a silicon nitride film were formed as a plastic lens antireflection film.

As the workpiece W, a plastic convex lens having a diameter of 50 mm was used. After being set on the lens holding means 102, the inside of the plasma processing chamber was evacuated via the exhaust system (24 to 26) to reduce the pressure to 10 ^-7 Torr. Nitrogen gas was introduced into the processing chamber at a flow rate of 150 sccm, and monosilane gas was introduced at a flow rate of 100 sccm through the plasma processing gas discharge port 107a.

Next, the valve 26 provided in the exhaust system (24 to 26) was adjusted to maintain the inside of the processing chamber at 5 mTorr. Then, 3.0 kW of electric power was supplied from the microwave power source 6 of 2.45 GHz, and the distribution ratio was 0.7 inside / 0.3 outside.
And supplied to the plasma processing chamber through the multi-endless annular waveguide 103 adjusted to.

[0344] Thus, plasma was generated in the plasma processing chamber. At this time, the plasma processing gas discharge port 107
The nitrogen gas introduced through a is excited and decomposed in the plasma processing chamber to become active species such as nitrogen atoms, is transported in the direction of the lens, reacts with the monosilane gas, and a silicon nitride film having a thickness of 21 nm is formed on the lens. It was formed with.

Next, the plasma processing gas discharge port 107a
, An oxygen gas was introduced into the processing chamber at a flow rate of 200 sccm, and a monosilane gas was introduced into the processing chamber at a flow rate of 100 sccm. Next, the valve 26 provided in the exhaust system (24 to 26) was adjusted to maintain the processing chamber at 1 mTorr.
Then, from the microwave power source 6 of 2.45 GHz, 2.0
kW of power was supplied to the plasma generation chamber through the multiple endless annular waveguide 103 whose distribution ratio was adjusted to 0.7 inside / 0.3 outside.

[0346] Thus, plasma was generated in the plasma processing chamber. At this time, the plasma processing gas discharge port 107
The oxygen gas introduced via a is excited and decomposed in the plasma processing chamber to become active species such as oxygen atoms, is transported in the direction of the lens, reacts with the monosilane gas, and a silicon oxide film is formed on the lens with a thickness of 86 nm. It was formed with. After the film formation, the film formation speed and the reflection characteristics were evaluated.

The deposition rates of the obtained silicon nitride film and silicon oxide film were 320 nm / min and 380 n, respectively.
m / min, and the film quality was confirmed to be extremely good optical characteristics with a reflectivity around 500 nm of 0.25%.

(Example 5) A silicon oxide film for an interlayer insulating film of a semiconductor element was formed using the microwave plasma processing apparatus shown in FIG.

As the workpiece W, a P-type single crystal silicon wafer (plane orientation <100>, resistivity 10 Ωcm) having an Al pattern (line and space 0.5 μm) formed on the uppermost portion and having a diameter of about 300 mm was used. used.

First, a silicon wafer was set on the holding means 102. The plasma processing chamber was evacuated through the exhaust system (24 to 26) to reduce the pressure to a value of 10 ^-7 Torr. Subsequently, the heater-114 was energized to heat the silicon wafer to 300 ° C., and the substrate was kept at this temperature. Oxygen gas is supplied through the plasma processing gas discharge port 107a.
At a flow rate of 0 sccm, and a monosilane gas of 200 s
It was introduced into the processing chamber at a flow rate of ccm.

Next, the valve 26 provided in the exhaust system (24 to 26) was adjusted, and the inside of the plasma processing chamber was 30 mTo
rr. Then, 300 W of power is applied to the holding means 102 through a 13.56 MHz high frequency applying means, and 2.0 kW of power is supplied from a 2.45 GHz microwave power supply, with a distribution ratio of 0.5 inside / 0.5 outside. 5
And supplied to the plasma processing chamber through the multi-endless annular waveguide 103 adjusted to.

[0352] Thus, plasma was generated in the plasma processing chamber. The oxygen gas introduced through the plasma processing gas supply means 107 is excited and decomposed into active species in the plasma processing chamber, transported in the direction of the silicon wafer, reacts with the monosilane gas, and forms a silicon oxide film on the silicon wafer. It was formed with a thickness of 0.8 μm.

At this time, the ion species are accelerated by the RF bias and are incident on the substrate to cut the film on the pattern and improve the flatness. After the treatment, the film forming speed, uniformity, dielectric strength, and step coverage were evaluated. The step coverage was evaluated by observing a cross section of the silicon oxide film formed on the Al wiring pattern with a scanning electron microscope (SEM) and observing voids.

The obtained silicon oxide film has a good film forming rate and uniformity of 270 nm / min ± 2.3%, a film quality of 9.3 MV / cm, a void-free film and a good film. Was confirmed.

(Example 6) Using the microwave plasma processing apparatus shown in FIG. 26, the interlayer insulating film for a semiconductor element was etched.

As an object to be processed, a 1 μm thick interlayer Si was formed on an Al pattern (line and space 0.35 μm).
A P-type single crystal silicon wafer (plane orientation <100>, resistivity 10 Ωcm) having a diameter of about 300 mm and an O ₂ film formed thereon was used.

First, after the silicon wafer was set on the holding means 102, the inside of the plasma generation chamber was evacuated via the exhaust system (24 to 26) to reduce the pressure to 10 ^-7 Torr. CF through the plasma processing gas emission port 107a
₄ was introduced into the plasma processing chamber at a flow rate of 300 sccm. Next, the valve 26 provided in the exhaust system (24 to 26) was adjusted, and the pressure in the plasma processing chamber was maintained at 5 mTorr.

Next, a power of 2.0 kW is applied from the microwave power source 6 of 2.45 GHz to the power holding means 102 of 300 W via a high frequency applying means 302 of 13.56 MHz, and the distribution ratio is set to 0.4 on the inner side. / Outside 0.6
And supplied to the plasma processing chamber through the multi-endless annular waveguide 103 adjusted to. Thus, plasma was generated in the plasma processing chamber.

The CF ₄ gas introduced through the plasma processing gas discharge port 107a is excited and decomposed into active species in the plasma processing chamber, transported in the direction of the silicon wafer, and oxidized by ions accelerated by a self-bias. The silicon film has been etched. The cooler 414 raised the substrate temperature only to 90 ° C. After the etching, the etching rate, the selectivity, and the etching shape were evaluated. The etched shape was evaluated by observing the cross section of the etched silicon oxide film with a scanning electron microscope (SEM).

Etching Rate and Selectivity to Polysilicon 6
It was confirmed to be 90 nm / min, 21 which was good, the etching shape was almost vertical, and the microloading effect was small.

Example 7 A polysilicon film serving as a gate electrode for a semiconductor element was etched using the microwave plasma processing apparatus shown in FIG.

As a processing target, a P-type single crystal silicon wafer (plane orientation <100>, resistivity 10 Ωcm) having a diameter of 300 mm and a polysilicon film formed on the uppermost portion was used.

First, after the silicon wafer was set on the holding means 102, the inside of the plasma processing chamber was evacuated via the exhaust system (24 to 26) to reduce the pressure to 10 ^-7 Tirr. CF through the plasma processing gas emission port 107a
_Four gases were introduced into the plasma processing chamber at a flow rate of 300 sccm and oxygen at a flow rate of 20 sccm.

Next, the valve 26 provided in the exhaust system (24 to 26) was adjusted, and the inside of the plasma processing chamber was adjusted to 2 mTorr.
r. Next, RF bias applying means 3
02, a high frequency power of 300 kHz of 400 kHz is applied to the wafer, and 1.5 kW of power is supplied from a microwave power supply of 2.45 GHz to a multi-endless terminal whose distribution ratio is adjusted to 0.45 inside / 0.55 outside. The liquid was supplied into the plasma processing chamber through the annular waveguide 103.

[0365] Thus, plasma was generated in the plasma processing chamber. The CF ₄ gas and oxygen introduced through the plasma processing gas discharge port 107a are excited and decomposed into active species in the plasma processing chamber, are transported in the direction of the silicon wafer, and are polysulfated by ions accelerated by a self-bias. The film was etched. Cooler 414
As a result, the substrate temperature rose only to 80 ° C.

After the etching, the etching rate, the selectivity,
And the etching shape was evaluated. The etched shape was evaluated by observing the cross section of the etched polysilicon film with a scanning electron microscope (SEM).

The etching rate and the selectivity ratio to SiO ₂ were good at 870 nm / min and 26, respectively, and it was confirmed that the etching shape was vertical and the microloading effect was small.

Example 8 Photoresist ashing was performed in the same manner as in Example 9 using the apparatus shown in FIG.

[0369] As a result, uniform processing without residue could be performed in a short time.

[0370]

According to the present invention, by arranging a plurality of annular waveguides concentrically so that the H-plane with slots is coplanar, microwaves having a uniform and large-area intensity distribution are radiated.・ Can be supplied. Thus, a diameter of about 30
It is possible to satisfactorily perform plasma processing on an object to be processed having a wafer area of 0 mm or a large area equal to or larger than the wafer.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing main components of a plasma processing apparatus.

FIG. 2 is a schematic view showing a longitudinal section of the plasma processing apparatus.

FIG. 3 is a schematic diagram showing a state of propagation and radiation of microwaves in a microwave supply device.

FIG. 4 is a schematic diagram showing positions of a slot, a gas outlet, and an object to be processed in the plasma processing apparatus.

FIG. 5 is a schematic view showing a microwave supply device.

FIG. 6 is a schematic diagram showing a microwave supply device.

FIG. 7 is a plan view showing a configuration of a slot used in the present invention.

FIG. 8 is a schematic diagram showing an example of another slot arrangement used in the present invention.

FIG. 9 is a schematic diagram illustrating a configuration of a gas supply unit.

FIG. 10 is a view showing a flowchart of a plasma processing method.

FIG. 11 is a schematic view showing another plasma processing apparatus.

FIG. 12 is a schematic view showing still another plasma processing apparatus.

FIG. 13 is a schematic view showing another plasma processing apparatus.

FIG. 14 is a schematic view showing still another plasma processing apparatus.

FIG. 15 is a schematic view showing another plasma processing apparatus.

FIG. 16 is a schematic diagram showing an appearance and a cross section of a microwave supply device.

FIG. 17 is a schematic diagram showing a cross section of a microwave introduction unit of the microwave supply device.

FIG. 18 is a schematic view showing a slotted H-plane of the microwave supply device.

FIG. 19 is a schematic diagram showing a microwave supplier according to an embodiment of the present invention.

FIG. 20 is a schematic diagram showing a microwave supply device and a plasma processing apparatus using the same according to another embodiment of the present invention.

FIG. 21 is a schematic diagram showing an example of an arrangement of slots used in a multiple annular waveguide according to another embodiment of the present invention.

FIG. 22 is a schematic view showing various structures of a microwave distribution and introduction unit used in the present invention.

FIG. 23 is a diagram illustrating a glass of a change in microwave radiation intensity with respect to a tilt angle of a distributor.

FIG. 24 is a schematic view showing another plasma processing apparatus of the present invention.

FIG. 25 is a schematic view showing still another plasma processing apparatus of the present invention.

FIG. 26 is a schematic view showing another plasma processing apparatus of the present invention.

FIG. 27 is a schematic view showing still another plasma processing apparatus of the present invention.

FIG. 28 is a schematic cross-sectional view of a conventional microwave supply device.

FIG. 29 is a schematic longitudinal sectional view of a conventional microplasma processing apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Container 2 Holding means 3 Microwave supply device 4 Dielectric window 7 Gas supply means 7a Gas discharge port W Workpiece

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI H01L 21/3065 H01L 21/31 C 21/31 H01Q 21/06 H01Q 21/06 H01L 21/302 B

Claims (9)

[Claims] 1. An annular waveguide having a planar H-plane having a plurality of slots provided apart from each other and a rectangular section perpendicular to the direction in which microwaves travel, the H-plane is coplanar. A plurality of concentrically arranged microwave supply devices for supplying microwaves from the plurality of slots provided on the planar H surface of each annular waveguide. 2. A ring formed by connecting the centers of the respective waveguides constituting the plurality of annular waveguides has an integral length that is an integral multiple of the guide wavelength, and along the ring at least the guide wavelength. The microwave supply according to claim 1, wherein the slots are formed radially at half intervals. 3. The microwave feeder according to claim 1, wherein the length of the slot perpendicular to the traveling direction of the microwave is in a range of １ ／ to ／ of a guide wavelength. 4. An introduction port for microwaves to each of the annular waveguides is provided on the other H plane, and the introduction section distributes the microwaves in two directions parallel to the H plane. 2. A means for providing propagation on both sides in an annular waveguide.
The microwave supply device according to claim 1. 5. The microwave feeder according to claim 1, wherein each of the annular waveguides is an endless waveguide. 6. The annular waveguide has one annular waveguide.
2. The microwave supply device according to claim 1, wherein a microwave having a power sufficient to propagate over the circumference is supplied. 7. The microwave feeder according to claim 1, wherein the power is a microwave having a power sufficient to propagate through the annular waveguide two or more times. 8. The microwave feeder according to claim 1, wherein the circumference of the annular waveguide is determined so that a standing wave is generated therein. 9. A microwave feeder comprising a plurality of endless annular waveguides having different perimeters arranged concentrically, their planar H-planes being respectively coplanar, and a plurality of slots provided therein.