JP2003332241A - Microwave plasma treatment apparatus, microwave plasma treatment method, and structure manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a microwave plasma treatment apparatus which can control a reflection electric power and easily generate a discharge in a wide conditional range, a microwave plasma treatment method, and a structure manufacturing method. <P>SOLUTION: A desired electric power is supplied from a microwave power source into the plasma treatment chamber, then, the microwave, which is introduced into an endless loop waveguide 118 through a reflection limitation slot 110, is divided in two at an E branch 111 right and left, and are propagated. The divided microwaves interfere each other, and the antinodes of stationary waves 112 produce for each half of a wave length in the waveguide. Then, the microwave penetrates a dielectric window 107 through a slot 113 located to cross a surface current and is introduced into the plasma treatment chamber. A part of the microwave incident to the endless loop waveguide 118 returns as a reflection component in a direction of a power source, whereas the reflected electric power is limited to less than a half of the incident electric power by the reflection limitation slot 110. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a microwave plasma processing apparatus, a microwave plasma processing method, and a method of manufacturing a structure, which are capable of easily generating discharge in a wide range of conditions by limiting reflected power.

[0002]

2. Description of the Related Art A CVD (chemical vapor deposition) apparatus, an etching apparatus, an ashing apparatus and the like are known as plasma processing apparatuses using microwaves as excitation sources for generating plasma.

A CVD process using a microwave plasma CVD apparatus is performed as follows, for example. That is, the gas is introduced into the plasma generation chamber and the film formation chamber of the microwave plasma CVD apparatus, and at the same time, microwave energy is input to generate plasma in the plasma generation chamber to excite and decompose the gas. A deposited film is formed on the substrate to be processed arranged in the film chamber.

Further, the etching process of the substrate to be processed using the microwave plasma etching apparatus is performed as follows, for example. That is, an etchant gas is introduced into the processing chamber of the microwave plasma etching apparatus, and at the same time, microwave energy is input to excite and decompose the etchant gas to generate plasma in the processing chamber, which causes the plasma in the processing chamber. The surface of the arranged substrate to be processed is etched.

Further, the ashing process of the substrate to be processed using the so-called microwave plasma ashing device is performed as follows, for example. That is, by introducing ashing gas into the processing chamber of the microwave plasma ashing device and at the same time inputting microwave energy, the ashing gas is excited and decomposed to generate plasma in the processing chamber. The surface of the disposed substrate to be processed is ashed.

As described above, in various microwave plasma processing apparatuses, since microwaves are 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 or excited. Can be made. Therefore, according to the microwave plasma processing apparatus, gas ionization efficiency, excitation efficiency, and decomposition efficiency are high, and high-density plasma can be formed relatively easily.
In addition, high-quality processing can be performed at low temperature and at high speed.
Further, since the microwave has a property of transmitting the dielectric, the plasma processing apparatus can be configured as an electrodeless discharge type. Therefore, there is also an advantage that highly clean plasma processing can be performed.

In order to further increase the speed of such a microwave plasma processing apparatus, electron cyclotron resonance (EC
A plasma processing apparatus utilizing R: electron cyclotron resonance has been put into practical use. When the magnetic flux density is 87.5 mT, the ECR shows that the electron cyclotron frequency at which the electrons rotate around the lines of magnetic force coincides with the general microwave frequency of 2.45 GHz, and the electrons are resonantly absorbed by the microwaves. This is a phenomenon in which high-density plasma is generated by being accelerated. 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 facing surface of the substrate to be processed through the transmission window, and coaxial with the central axis of the plasma generation chamber. (NTT method) in which the divergent magnetic field is introduced via an electromagnetic coil provided around the plasma generation chamber;
i) The microwave transmitted through the waveguide is introduced into the bell-shaped plasma generating chamber from the facing surface of the substrate to be processed, and a magnetic field coaxial with the central axis of the plasma generating chamber is provided around the plasma generating chamber. Introduced via electromagnetic coil (Hitachi method); (iii) Microwave is introduced into the plasma generation chamber from the periphery via the Rizzitano coil, which is a type of cylindrical slot antenna, and the central axis of the plasma generation chamber A structure in which a coaxial magnetic field is introduced through an electromagnetic coil provided around the plasma generation chamber (rigitano method); (iv) The microwave transmitted through the waveguide is flat from the facing surface of the substrate to be processed. It is introduced into the cylindrical plasma generation chamber through the slot antenna of the above, and the loop-shaped magnetic field parallel to the antenna plane is introduced through the permanent magnet provided on the back surface of the planar antenna (planar slot antenna). Tena method), it is.

As an example of the microwave plasma processing apparatus,
In recent years, an apparatus using an endless annular waveguide having a plurality of slots formed on the H-plane has been proposed as a uniform and efficient introduction apparatus for microwaves (Japanese Patent No. 2886752 and Japanese Patent No. 2925535). Such a microwave plasma processing apparatus is shown in FIG. 6 (a), and its plasma generation mechanism is shown in FIG. 6 (b).

In this conventional microwave plasma processing apparatus, as shown in FIG.
01, a support 903 for supporting the substrate 902 to be processed,
A substrate temperature adjusting means 904 for adjusting the temperature of the substrate 902 to be processed is provided. Also, the plasma processing chamber 90
A gas introduction unit 905 for microwave plasma processing is provided inside the wall of No. 1. The exhaust 906 is performed below the substrate temperature adjusting unit 904. Further, on the plasma processing chamber 901, there is provided a microwave supplier 908 with a slot in which an endless annular waveguide 918 is formed. A flat plate-shaped dielectric window 907 that separates the plasma processing chamber 901 from the atmosphere side is embedded in the lowermost surface of the microwave supplier with slots 908, and the endless annular waveguide 918 and the dielectric window 907 are separated from each other. Slots 913 are formed at predetermined intervals therebetween. Microwaves are introduced into the plasma processing chamber 901 through the dielectric window 907.
An E branch 911 is formed on the upper portion of the microwave supplier with slots 908 to divide the microwave introduced from the outside into two in the endless annular waveguide 918.

Microwave plasma processing using the microwave plasma processing apparatus thus configured is performed as follows. First, the inside of the plasma processing chamber 901 is evacuated through an exhaust system (not shown). Then, the processing gas is introduced into the plasma processing chamber 901 at a predetermined flow rate through the gas introduction unit 905. Next, exhaust system (not shown)
By adjusting a conductance valve (not shown) provided in the plasma processing chamber 901, the inside of the plasma processing chamber 901 is maintained at a predetermined pressure.
Then, a desired power is supplied from a microwave power source (not shown) through the endless annular waveguide 918 to the plasma processing chamber 901.
Supply in. At this time, the microwave introduced into the endless annular waveguide 918 is divided into two parts on the left and right by the E branch 911 and propagates with a guide wavelength longer than the free space. The distributed microwaves interfere with each other, and an "antinode" of the standing wave 912 occurs for each 1/2 of the in-tube wavelength. Microwaves introduced into the plasma processing chamber 901 through the dielectric window 907 through the slot 913 provided so as to cross the surface current generate initial high-density plasma in the vicinity of the slot 913. In this state, the microwave incident on the interface between the dielectric window 907 and the initial high-density plasma cannot propagate into the initial high-density plasma, and the interface between the dielectric window 907 and the initial high-density plasma, that is, the dielectric window. 907 surface wave 9
Propagate as 14. Then, the surface waves 914 introduced from the slots 913 adjacent to each other interfere with each other,
A surface standing wave 915 having an “antinode” is generated for each half of the wavelength of the surface wave 914. Surface plasma 916 is generated by the surface standing wave 915. Further, the surface plasma 91
Bulk plasma 917 is generated by the diffusion of 6. The processing gas is the generated surface wave interference plasma (surface plasma 9
16) is excited, and the surface of the substrate 902 to be processed placed on the support 903 is processed. The "antinode" of each standing wave is located at a position marked with an upward or downward arrow in the region showing the standing wave 912 or the surface standing wave 915 in FIG. 6B.

By using such a microwave plasma processing apparatus, with a microwave power of 1 kW or more, an electron density of 10 ¹² cm ^-3 or more, and an electron density of 10 ¹² cm ^-3 or more can be obtained in a large diameter space of about 300 mm with uniformity. High-density low-potential plasma having a temperature of 3 eV or less and a plasma potential of 15 V or less can be generated. Therefore, the gas can be sufficiently reacted and supplied to the substrate in an active state, and the substrate surface damage due to incident ions can be reduced, so that high-quality, uniform and high-speed processing can be performed even at a low temperature.

[0013]

However, when the microwave plasma processing apparatus as described above is used, the reflected power from the microwave introducing means to the power supply direction becomes large depending on the processing conditions, and it is difficult to discharge. There is a problem that the power supply and / or the matching device may fail.

The present invention has been made in view of the above problems, and a microwave plasma processing apparatus, a microwave processing method, and a microwave processing method capable of easily generating a discharge in a wide condition range by limiting reflected power. An object is to provide a method for manufacturing a structure.

[0015]

A microwave plasma processing apparatus according to a first invention of the present application is a plasma processing chamber and a substrate-to-be-processed substrate mounted in the plasma processing chamber, on which a substrate to be processed is placed. Means, a dielectric window arranged to face the substrate-to-be-treated mounting means, and a microwave introduction means for introducing microwaves into the plasma processing chamber through the dielectric window. In the plasma processing apparatus, the microwave introduction means, a waveguide, a microwave introduction port for introducing microwaves into the waveguide,
A reflection limiting slot provided at the microwave introduction port so that the incident wave power is twice or more the reflected wave power.

A microwave plasma processing apparatus according to a second aspect of the present invention is the microwave plasma processing apparatus according to the first aspect, wherein the microwave introducing means has a flat plate-shaped multi-slot antenna using an endless annular waveguide. Characterize.

The microwave plasma processing apparatus according to the third invention of the present application is characterized in that, in the first or second invention, the waveguide constitutes a cavity resonator.

A microwave plasma processing apparatus according to a fourth invention of the present application is the microwave plasma processing apparatus according to any one of the first to third inventions, wherein n is a natural number, the natural wavelength of the microwave is λ _s ,
When the dielectric constant of the dielectric window is ε _d , the thickness of the dielectric window is approximately (2n−1) λ _s ε _d ^−1/2 / 4.

A microwave plasma processing apparatus according to a fifth invention of the present application is the microwave plasma processing apparatus according to any one of the first to fourth inventions, wherein the surface of the dielectric window on the plasma processing chamber side is in the plasma processing chamber. To the microwave reflection means provided at a position separated by an odd multiple of 1/4 of the natural wavelength of the microwave.

The microwave plasma processing apparatus according to the sixth invention of the present application is the microwave plasma processing apparatus according to any one of the first to fifth inventions, wherein the substrate to be processed is placed from the surface of the dielectric window on the plasma processing chamber side. The distance from the means is an odd multiple of 1/4 of the natural wavelength of the microwave.

A microwave plasma processing method according to a seventh invention of the present application is a step of placing a substrate to be processed on a substrate to be processed placing means provided in a plasma processing chamber, a waveguide,
The microwave introducing means for introducing microwaves into the waveguide, and the microwave introducing means provided with a reflection limiting slot provided so that the incident wave power is twice or more the reflected wave power Supplying microwave power to allow microwaves to be introduced into the plasma processing chamber by passing through a dielectric window arranged to face the substrate-to-be-processed mounting means.

The microwave plasma processing method according to the eighth invention of the present application is characterized in that, in the seventh invention, a film is formed on the substrate to be processed by a chemical vapor deposition method.

The microwave plasma processing method according to the ninth invention of the present application is characterized in that the substrate to be processed is subjected to etching processing.

A microwave plasma processing method according to a tenth invention of the present application is characterized in that, in the seventh invention, an ashing process is performed on the substrate to be processed.

The microwave plasma processing method according to the eleventh invention of the present application is characterized in that, in the seventh invention, a doping process is performed on the substrate to be processed.

According to a twelfth aspect of the present invention, a method of manufacturing a structure performs a microwave plasma treatment on the substrate to be treated by the microwave plasma treatment method according to any one of the seventh to eleventh aspects. It is characterized by having a process.

The present inventor has solved the above-mentioned problems in the conventional microwave plasma processing apparatus and made diligent efforts to achieve the above object. As a result, by providing a reflection limiting slot in the microwave introducing means, the reflected power can be reduced. It has been found that it is possible to provide a microwave plasma processing apparatus which can easily discharge in a wide range of conditions by limiting the above. The above-mentioned present inventions are all based on such knowledge.

[0028]

BEST MODE FOR CARRYING OUT THE INVENTION A microwave plasma processing apparatus, a microwave plasma processing method, and a structure manufacturing method according to embodiments of the present invention will be specifically described below with reference to the accompanying drawings.

(First Embodiment) First, a first embodiment of the present invention will be described. FIG. 1 is a schematic cross-sectional view showing the structure of the microwave plasma processing apparatus according to the first embodiment of the present invention. In the microwave plasma processing apparatus according to the first embodiment, as shown in FIG. 1, the temperature of the support 103 that supports the substrate 102 to be processed and the temperature of the substrate 102 to be processed are adjusted in the plasma processing chamber 101. Substrate temperature adjusting means 104 is provided. Further, a microwave plasma processing gas introduction unit 105 is provided inside the wall of the plasma processing chamber 101. The exhaust 106 is
It is performed below the substrate temperature adjusting means 104. Further, on the plasma processing chamber 101, there is provided a microwave supplier 108 with a slot in which an endless annular waveguide (waveguide) 118 is formed. The plasma processing chamber 10 is provided on the lowermost surface of the microwave supplier with slots 108.
A flat plate-shaped dielectric window 107 for separating 1 from the atmosphere side is embedded, and a plurality of slots 113 are formed at predetermined intervals between the endless annular waveguide 118 and the dielectric window 107. . Endless circular waveguide 1 through the dielectric window 107
Microwaves are introduced into the plasma processing chamber 101 from 18. The microwave introduced from the outside is guided by an endless annular waveguide 118 on the upper part of the microwave supplier with slots 108.
An E-branch 111 is formed so as to be divided into two in the left and right.
In this embodiment, the endless annular waveguide 118 is further added.
A reflection limiting slot 110 is provided at the entrance of the. The reflection limiting slot 110 is processed into a shape in which the power on the incident side is twice or more the power on the reflecting side, that is, the power on the reflecting side is less than ½ the power on the incident side.

In the following description, the surface of the endless annular waveguide on the side of the dielectric window (the surface on which a plurality of slots are formed at predetermined intervals) is referred to as a multi-slot surface, which corresponds to the microwave input side. The surface (the surface on which the reflection limiting slot is formed) is called the reflection limiting slot surface.

Next, a microwave plasma processing method using the microwave plasma processing apparatus configured as described above will be described. FIG. 2 is a schematic diagram showing a plasma generation mechanism in a processing method using the microwave plasma processing apparatus according to the first embodiment of the present invention.

First, the inside of the plasma processing chamber 101 is evacuated through an exhaust system (not shown). Then, the processing gas is introduced into the plasma processing chamber 101 at a predetermined flow rate through the gas introduction unit 105. Next, a conductance valve (not shown) provided in the exhaust system (not shown) is adjusted to maintain the inside of the plasma processing chamber 101 at a predetermined pressure.
Next, desired power is supplied from a microwave power source (not shown) through the endless annular waveguide 118 to the plasma processing chamber 101.
Supply in. At this time, the microwave introduced into the endless annular waveguide 118 via the reflection limiting slot 110 is divided into two parts to the left and right by the E branch 111, and propagates with a guide wavelength λ _g longer than the free space. The distributed microwaves interfere with each other, and a standing wave 112 is generated for each half of the guide wavelength.
"Belly" occurs. Microwaves are introduced into the plasma processing chamber 101 through the dielectric window 107 through the slot 113 provided so as to cross the surface current.

Although a part of the microwave incident on the endless annular waveguide 118 returns as a reflection component in the power supply direction, the reflection limiting slot 110 limits the reflection side power to less than 1/2 of the incidence side power. To be done.

Then, the microwave introduced into the plasma processing chamber 101 generates an initial high density plasma in the vicinity of the slot 113. In this state, the microwave incident on the interface between the dielectric window 107 and the initial high-density plasma is
The dielectric window 107 cannot propagate in the initial high-density plasma.
And the initial high-density plasma, that is, the surface of the dielectric window 107 propagates as a surface wave 114. Then, the surface waves 114 introduced from the slots 113 adjacent to each other interfere with each other, and a surface standing wave 115 having an “antinode” is generated for each half of the wavelength of the surface wave 114. This surface standing wave 11
5, the surface plasma 116 is generated. Further, the bulk plasma 117 is generated by the diffusion of the surface plasma 116. The processing gas is excited or ionized by the generated surface wave interference plasma (surface plasma 116), or reacts and is activated to process the surface of the substrate 102 to be processed placed on the support 103. The "antinode" of each standing wave is located at a position marked with an upward or downward arrow in the region showing the standing wave 112 or the surface standing wave 115 in FIG.

As described above, according to the first embodiment, the reflection of the microwave incident on the endless annular waveguide 118 is limited by the reflection limiting slot 110. For this reason,
It is possible to stably secure stable discharge. It is also possible to reduce the occurrence rate of failures of the power supply and the matching box.

Next, a specific example of the first embodiment will be described. In this example, the reflection limiting slot 110 has a rectangular shape with a length of 80 mm and a width of 4 mm. The material of the dielectric window 107 is anhydrous synthetic quartz, the thickness is 16 mm, and the relative dielectric constant at the microwave frequency of 2.45 GHz used is 3.8. The dimension of the inner wall cross section of the endless annular waveguide 118 is 27 mm × 96 mm, and the center diameter of the waveguide is 202 mm. That is, the waveguide circumference is λ
_It is 4 times the _g . Microwave feeder with slot 1
The material of No. 08 uses Al in order to suppress the propagation loss of microwaves. Microwave feeder with slot 1
A slot 113 for introducing microwaves into the plasma processing chamber 101 is formed on the H surface of 08. The shape of the slot 113 is a rectangular shape having a length of 40 mm and a width of 4 mm. Further, the slots 113 are radially formed at intervals of ½ of the guide wavelength. The in-tube wavelength depends on the frequency of the microwave used and the size of the cross section of the waveguide, but when the microwave of the frequency of 2.45 GHz and the waveguide of the above size are used, the wavelength is about It is 158.8 mm. In this specific example, eight slots 113 are formed at intervals of about 45 degrees. Microwave supplier with slot 10
To the microwave input side of 8, a 4E tuner, a directional coupler, an isolator, and a microwave power source (not shown) having a frequency of 2.45 GHz are sequentially connected.

(Second Embodiment) Next, a second embodiment of the present invention will be described. FIG. 3 is a schematic sectional view showing the structure of the microwave plasma processing apparatus according to the second embodiment of the present invention. In the microwave plasma processing apparatus according to the second embodiment, as shown in FIG. 3, the temperature of the support body 203 that supports the substrate 202 to be processed and the temperature of the substrate 202 to be processed are adjusted in the plasma processing chamber 201. Substrate temperature adjusting means 204 is provided. Further, a microwave plasma processing gas introduction unit 205 is provided inside the wall of the plasma processing chamber 201. Further, in the present embodiment, the reflecting surface 209 is projected inward from the wall at an intermediate position in the height direction of the plasma processing chamber 201.
Is provided. The shape of the reflecting surface 209 is, for example, 80
It is a rectangle of about 4 mm. Further, as the shape of the reflecting surface 209, various shapes having a length of about 40 mm in the direction traversing the surface current may be applied similarly to the slot of the multi-slot surface. However, it is not limited to this.
The exhaust 206 is performed below the substrate temperature adjusting unit 204. Further, on the plasma processing chamber 201, there is provided a microwave supplier 208 with a slot in which an endless annular waveguide (waveguide) 218 is formed. On the lowermost surface of the microwave supplier with slots 208, a flat dielectric window 20 for separating the plasma processing chamber 201 from the atmosphere side is provided.
7 are embedded, and a plurality of slots 2 are provided at a predetermined interval between the endless annular waveguide 218 and the dielectric window 207.
13 is formed. Microwaves are transmitted from the endless annular waveguide 218 through the dielectric window 207 to the plasma processing chamber 20.
Introduced in 1. An E branch 211 that divides the microwave introduced from the outside into two in the endless annular waveguide 218 is formed on the upper portion of the microwave supplier with slot 208. Further, a reflection limiting slot 210 is provided at the entrance of the endless annular waveguide 218. Similar to the first embodiment, the shape of the reflection limiting slot 210 is processed so that the power on the incident side is twice or more the power on the reflecting side.

The reflection limiting slot 210 has a shape of length 8
It has a rectangular shape of 0 mm and a width of 4 mm. The material of the dielectric window 207 is anhydrous synthetic quartz, and the thickness is 16 mm. The dimension of the inner wall cross section of the endless annular waveguide 218 is 27 mm × 96 mm.
And the center diameter of the waveguide is 202 mm. That is,
The circumference of the waveguide is four times the guide wavelength λ _g . As the material of the microwave supplier with slots 208, Al is used in order to suppress the propagation loss of microwaves. A slot 21 for introducing microwaves into the plasma processing chamber 201 is provided on the H surface of the microwave supplier 208 with slots.
3 is formed. The shape of the slot 213 has a length of 40
mm, and a rectangular shape with a width of 4 mm. In addition, the slot 213
Are radially formed at intervals of 1/2 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. When the microwave of the frequency of 2.45 GHz and the guide of the above size are used,
It is about 158.8 mm. In this example, slot 2
Eight 13 are formed at intervals of about 45 degrees. 4E is provided on the microwave input side of the microwave supplier with slot 208.
Tuner, directional coupler, isolator and 2.45G
A microwave power source (not shown) having a frequency of Hz is connected in sequence.

The distance from the multi-slot surface of the endless annular waveguide 218 to the reflecting surface 209, and the reflecting surface 20.
The distances from 9 to the upper surface of the substrate support 203 to be treated are 91.8 mm and 30.6 mm, respectively. That is, these intervals are defined by the natural wavelength of the microwave of 2.45 GHz, 122.
The values are set to 3/4 times and 1/4 times the value of 4 mm.

The microwave plasma processing method using the microwave plasma processing apparatus according to the second embodiment having the above structure is performed in the same manner as in the first embodiment.
That is, first, the inside of the plasma processing chamber 201 is evacuated through an exhaust system (not shown). Subsequently, the processing gas is introduced into the plasma processing chamber 201 around the gas introduction means 20.
The gas is introduced into the plasma processing chamber 201 at a predetermined flow rate through 5. Next, the conductance valve (not shown) provided in the exhaust system (not shown) is adjusted to adjust the plasma processing chamber 2
The inside of 01 is maintained at a predetermined pressure. Endless annular waveguide 21
A desired electric power is supplied to the plasma processing chamber 201 from a microwave power source (not shown) via 8. At this time, the processing gas introduced from the periphery is excited, ionized or reacted by the generated high density plasma to be activated, and the support 20
The surface of the substrate 202 to be processed placed on the substrate 3 is processed.

According to the second embodiment as described above, the same effect as that of the first embodiment can be obtained. Further, as will be described later, a resonator is provided between the multi-slot surface and the microwave reflection surface. Therefore, the microwave electric field in the vicinity of the surface of the dielectric window is strengthened, and the effect of facilitating discharge is also obtained.

The shape of the reflection limiting slot is not particularly limited. For example, a rectangular shape, an elliptical shape, or a dumbbell shape may be used as long as the power on the incident side is twice or more the power on the reflecting side, and the effect of the present invention can be obtained.

Further, in order to make the low reflection characteristics of the microwave plasma processing apparatus of the present invention more effective, it is desirable that at least one of the following three conditions be satisfied at the same time. (1) It is desirable to form a cavity resonator between the reflection limiting slot surface and the multi-slot surface. If this condition is satisfied, the multi-slot electric field is strengthened, and microwaves can be efficiently introduced into the plasma processing chamber. (2) The thickness of the dielectric window is approximately (2n-1) λ _s · ε _d ^-1/2
/ 4 is desirable. Here, n is a natural number, λ _s is the microwave natural wavelength, and ε _d is the dielectric constant of the dielectric window. If this condition is satisfied, interference reflection on the front and back surfaces of the dielectric window is prevented, and microwaves can be efficiently introduced into the plasma processing chamber. (3) It is desirable that the substrate support means or the microwave reflecting surface to be processed is provided at a position that is an odd multiple of λ _s / 4 from the lower surface of the dielectric window on the plasma processing chamber side. When this condition is satisfied, a resonator is formed between the multi-slot surface and the substrate supporting means to be treated or the microwave reflecting surface, the microwave electric field near the surface of the dielectric window is strengthened, and discharge is facilitated. Become. The second embodiment satisfies this condition.

The material of the dielectric window used in the microwave plasma processing apparatus of the present invention is applicable as long as it has a sufficient mechanical strength and a small dielectric loss so that the microwave transmittance is sufficiently high. For example, quartz, alumina (sapphire), aluminum nitride, fluorocarbon polymer (Teflon (registered trademark)) and the like are most suitable.

As the material of the microwave supplier with a slot used in the microwave plasma processing apparatus of the present invention, a conductive material can be used, but in order to suppress microwave propagation loss as much as possible, Al having high conductivity is used. , Cu, Ag /
Cu-plated stainless steel or the like is most suitable. The direction of the inlet of the slotted microwave feeder used in the present invention is such that it can efficiently introduce microwaves into the endless annular waveguide (microwave propagation space) in the slotted microwave feeder. , Parallel to the H-plane and tangential to the propagation space, or perpendicular to the H-plane and divided into two in the lateral direction of the propagation space at the introduction portion. The shape of the slot on the dielectric window side of the microwave supplier with slots used in the present invention is rectangular or elliptical as long as the length in the direction perpendicular to the microwave propagation direction is about ¼ of the guide wavelength. However, it may be dumbbell-shaped or anything. Further, it is optimal that the spacing between these slots is 1/2 of the guide wavelength so that electric fields that cross the slots are mutually strengthened due to interference.

In the microwave plasma processing apparatus and 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, any magnetic field perpendicular to the electric field generated in the width direction of the slot can be applied. As the magnetic field generating means, a permanent magnet other than a coil can be used. When using a coil, a water cooling mechanism or other cooling means such as air cooling may be used to prevent overheating.

In order to improve the quality of the treatment, the surface of the substrate to be treated may be irradiated with ultraviolet light. Any light source that emits light that is absorbed by the substrate to be treated or the gas adhering to the substrate to be treated can be applied, and an excimer laser, an excimer lamp, a rare gas resonance line lamp, a low-pressure mercury lamp, or the like is suitable. .

In the microwave plasma processing method of the present invention
The pressure inside the plasma processing chamber is 0.1 mTorr (approx.
1.33 x 10^-2Pa) to 10 Torr (about 1.33)
× 10 ³Pa) is preferable and 10 mT
orr (about 1.33 Pa) to 5 Torr (about 6.67)
× 10²The range of Pa) is more preferable.

Next, as a description of an embodiment of the microwave plasma processing method according to the present invention, a method of manufacturing a structure, for example, a semiconductor device will be described with reference to FIGS. 4 (a) to 4 (e).

In the method of manufacturing this structure, first, referring to FIG.
As shown in (a), an inorganic substance such as silicon oxide, silicon nitride, silicon oxynitride, aluminum oxide, tantalum oxide, or tetrafluoro is formed on the object to be processed 1 such as a silicon substrate by a CVD device or a surface improving device. The insulating film 2 made of an organic material such as ethylene or polyaryl ether is formed.

Next, as shown in FIG. 4B, a photoresist is applied and baked to form a photoresist layer 3.

Next, as shown in FIG. 4C, a hole pattern latent image is formed by an exposure device, and this is developed to form a photoresist pattern 3a having holes 4.

After that, as shown in FIG. 4D, the insulating film 2 under the photoresist pattern 3a is etched by an etching device to form a hole 5.

Then, as shown in FIG. 4E, the photoresist pattern 3a is removed by ashing using an ashing device.

In this way, the structure having the insulating film with holes is obtained.

Subsequently, when depositing a conductor or the like in the hole, it is also preferable to clean the inside of the hole by a cleaning device or the like in advance.

The microwave plasma processing apparatus according to the present invention can be used as at least one of the CVD apparatus, the surface reforming apparatus, the etching apparatus and the ashing apparatus used in the above steps.

Next, referring to FIGS. 5A to 5C,
As a description of another embodiment of the microwave plasma processing method according to the present invention, another manufacturing method of a structure, for example, a semiconductor device will be described.

In the method of manufacturing this structure, first, referring to FIG.
As shown in (a), a metal such as aluminum, copper, molybdenum, chromium, or tungsten, or an alloy containing at least one of these metals as a main component is provided on the object 1 to be processed such as a silicon substrate. A conductor pattern or a polycrystalline silicon pattern (here, line and space 6) made of is formed.

Next, as shown in FIG. 5B, the insulating film 7 is formed by a CVD device or the like.

Next, after forming a photoresist pattern (not shown), a hole 8 is formed in the insulating film 7 by an etching apparatus as shown in FIG. 5 (c).

Thereafter, the photoresist pattern is removed by an ashing device or the like to obtain a structure as shown in FIG. 5 (c).

The microwave plasma processing apparatus according to the present invention can be used as a CVD apparatus, an etching apparatus, and an ashing apparatus used in the above-mentioned steps, but as will be described later, it is limitedly applied thereto. is not.

The formation of the deposited film by the microwave plasma processing method of the present invention is performed by appropriately selecting the gas to be used. Si ₃ N ₄ , SiO ₂ , SiOF, Ta ₂ O ₅ , Ti
Insulating film of O ₂ , TiN, Al ₂ O ₃ , AlN, MgF _2, etc.,
a (amorphous) -Si, poly-Si, SiC, Ga
It is possible to efficiently form various deposited films such as a semiconductor film of As or the like, a metal film of Al, W, Mo, Ti, Ta or the like.

The substrate to be treated by the plasma treatment method of the present invention may be made of a semiconductor, may be conductive, or may be electrically insulating.

As the conductive substrate, Fe, Ni,
Cr, Al, Mo, Au, Nb, Ta, V, Ti, P
Examples thereof include metals such as t and Pb or alloys thereof, such as brass and stainless steel.

Insulating substrates to be treated include SiO ₂ -based quartz, various types of glass, Si ₃ N ₄ , NaCl, KCl, and Li.
Inorganic substances such as F, CaF ₂ , BaF ₂ , Al ₂ O ₃ , AlN and MgO, films of organic substances such as polyethylene, polyester, polycarbonate, cellulose acetate, polypropylene, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyamide and polyimide, A sheet etc. are mentioned.

The direction of the gas introducing means used in the plasma processing apparatus of the present invention is such that the gas passes through the plasma region generated in the vicinity of the dielectric window and is then sufficiently supplied in the vicinity of the center and then the surface of the substrate from the center Optimally, it has a structure that allows the gas to be blown towards the dielectric window so that it flows towards the periphery.

As a gas used for forming a thin film on a substrate by the CVD method, a generally known gas can be used.

As a raw material gas containing Si atoms to be introduced into the plasma processing chamber through the processing gas introducing means for forming a Si-based semiconductor thin film such as a-Si, poly-Si, or SiC, SiH ₄ , Inorganic silanes such as Si ₂ H ₆ , tetraethylsilane (TES), tetramethylsilane (T
MS), dimethylsilane (DMS), dimethyldifluorosilane (DMDFS), dimethyldichlorosilane (D
Organosilanes such as MDCS), SiF ₄ , Si ₂ F ₆ , S
i ₃ F ₈ , SiHF ₃ , SiH ₂ F ₂ , SiCl ₄ , Si ₂ C
l ₆ , SiHCl ₃ , SiH ₂ Cl ₂ , SiH ₃ Cl, Si
Examples thereof include halogenated silanes such as Cl ₂ F ₂ and the like, which are in a gas state at normal temperature and pressure or which can be easily gasified. Further, as the additive gas or carrier gas which may be introduced by mixing with the Si source gas in this case, H ₂ , H
Examples thereof include e, Ne, Ar, Kr, Xe and Rn.

As the raw material containing Si atoms introduced through the processing gas introducing means for forming a Si compound type thin film such as Si ₃ N ₄ or SiO ₂ , SiH ₄ and Si ₂ H _{6 are used.}
Inorganic silanes such as tetraethoxysilane (TEO
S), tetramethoxysilane (TMOS), octamethylcyclotetrasilane (OMCTS), dimethyldifluorosilane (DMDFS), dimethyldichlorosilane (DMDCS), and other organic silanes, SiF ₄ , Si
₂ F ₆ , Si ₃ F ₈ , SiHF ₃ , SiH ₂ F ₂ , SiCl ₄ ,
Si ₂ Cl ₆ , SiHCl ₃ , SiH ₂ Cl ₂ , SiH ₃ C
1, halogenated silanes such as SiCl ₂ F ₂ , and the like, which are in a gas state at normal temperature and pressure or which can be easily gasified. Further, in this case, as the nitrogen source gas or the oxygen source gas which are simultaneously introduced, N ₂ , NH ₃ , N ₂ H ₄ , hexamethyldisilazane (HMDS), O ₂ , O ₃ and H are used.
₂ O, NO, N ₂ O, NO _{2 and the} like can be mentioned.

As the raw material containing metal atoms introduced through the processing gas introduction means when forming a metal thin film of Al, W, Mo, Ti, Ta or the like, trimethyl aluminum (TMAl) and triethyl aluminum (TEA) are used.
l), triisobutylaluminum (TIBAl), dimethylaluminum hydride (DMAlH), tungsten carbonyl (W (CO) ₆ ), molybdenum carbonyl (Mo (CO) ₆ ), trimethylgallium (TMG)
a), triethylgallium (TEGa), tetraisopropoxytitanium (TIPOTi), pentaethoxytantalum (PEOTa) and other organic metals, AlCl ₃ , WF ₆ ,
Examples thereof include metal halides such as TiCl ₃ and TaCl ₅ . Further, as the additive gas or carrier gas which may be introduced by mixing with the Si source gas in this case, H ₂ , H
Examples thereof include e, Ne, Ar, Kr, Xe and Rn.

Al ₂ O ₃ , AlN, Ta ₂ O ₅ , TiO ₂ ,
As a raw material containing a metal atom to be introduced through a processing gas introducing means when a metal compound thin film such as TiN or WO ₃ is formed, trimethylaluminum (TMAl),
Triethyl aluminum (TEAl), triisobutyl aluminum (TIBAl), dimethyl aluminum hydride (DMAlH), tungsten carbonyl (W (CO) ₆ ), molybdenum carbonyl (Mo (C
O) ₆ ), trimethylgallium (TMGa), triethylgallium (TEGa), tetraisopropoxytitanium (TIPOTi), pentaethoxytantalum (PEOT)
a) or other organic metal, AlCl ₃ , WF ₆ , TiCl ₃ , T
Examples thereof include metal halides such as aCl ₅ . Further, in this case, as the oxygen source gas or the nitrogen source gas introduced at the same time, O ₂ , O ₃ , H ₂ O, NO, N ₂ O, NO ₂ ,
N ₂ , NH ₃ , N ₂ H ₄ , hexamethyldisilazane (HMD
S) and the like.

As the etching gas introduced from the processing gas introduction port when etching the surface of the substrate to be treated, F ₂ , CF ₄ , CH ₂ F ₂ , C ₂ F ₆ , C ₃ F ₈ and C ₄ F are used. ₈ ,
CF ₂ Cl ₂ , SF ₆ , NF ₃ , Cl ₂ , CCl ₄ , CH ₂ C
L ₂ , C ₂ Cl _{6 and the} like can be mentioned.

As the ashing gas to be introduced from the processing gas introduction port when the organic components on the surface of the substrate to be treated such as photoresist are removed by ashing, O ₂ , O ₃ , and H are used.
₂ O, NO, N ₂ O, NO ₂ , H _{2 and the} like can be mentioned.

When the microwave plasma processing apparatus and processing method of the present invention is also applied to surface modification, by appropriately selecting the gas to be used, for example, Si, Al, Ti as the substrate to be processed or the surface layer, Using Zn, Ta or the like, it is possible to perform an oxidation treatment or a nitriding treatment on the substrate or the surface layer to be treated, or a doping treatment of B, As, P or the like. Further, the film forming technique adopted in the present invention can be applied to the cleaning method. In that case, it can also be used for cleaning oxides or organic substances or heavy metals.

Oxidizing gas introduced through the processing gas introduction port when the substrate to be treated is subjected to the oxidation surface treatment is O
₂ , O ₃ , H ₂ O, NO, N ₂ O, NO _{2 and the} like can be mentioned.
Further, as the nitriding gas introduced through the processing gas introduction port when the substrate to be treated is subjected to the nitriding surface treatment, N ₂ , N
H ₃ , N ₂ H ₄ , hexamethyldisilazane (HMDS) and the like can be mentioned.

The organic substance on the surface of the substrate to be treated is cleaned.
Or on the surface of the substrate to be processed such as photoresist
Introduce from the gas inlet when removing components by ashing
O as a cleaning / ashing gas₂,
O₃, H₂O, NO, N₂O, NO ₂, H₂Etc.
It Also, the inorganic substance on the surface of the substrate to be treated is cleaned.
In the case of the cleaner introduced from the gas inlet for plasma generation
As the gas for ringing, F₂, CF_Four, CH₂F₂, C₂F₆,
C_FourF₈, CF₂Cl₂, SF₆, NF₃Etc.

[0079]

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

Example 1 Photoresist ashing was performed using the microwave plasma processing apparatus according to the first embodiment shown in FIG.

Interlayer SiO ₂ is used as the substrate 102 to be processed.
A silicon (Si) substrate (φ300 mm) was used immediately after the film was etched to form a via hole.

First, the target substrate (Si substrate) 102 is placed on the target substrate support 103, and then the temperature adjusting means 1 is used.
The heater as 04 is used to heat up to 250 ° C., and the inside of the plasma processing chamber 101 is evacuated through an exhaust system (not shown) to 10 ⁻⁴ Torr (about 1.33 × 10 ⁻² Pa).
The pressure was reduced to. Oxygen gas is supplied through the plasma processing gas introduction port 105 at a flow rate of 2 slm to the plasma processing chamber 101.
Introduced in.

Then, a conductance valve (not shown) provided in the exhaust system (not shown) is adjusted to set the processing chamber 1
The inside of 01 was maintained at 1.5 Torr (about 2.00 × 10 ² Pa). Power of 2.5 kW was supplied from the 2.45 GHz microwave power source into the plasma processing chamber 101 through the endless annular waveguide 118.

Thus, plasma was generated in the plasma processing chamber 101. At this time, the oxygen gas introduced through the plasma processing gas introduction port 105 is discharged into the plasma processing chamber 1
In 01, it was excited, decomposed, and reacted to become oxygen atoms, which were transported to the substrate (Si substrate) 102 to be processed, the photoresist on the substrate 102 to be processed was oxidized, and the photoresist was vaporized and removed. After the ashing, the gate dielectric breakdown evaluation, the ashing speed and the substrate surface charge density were evaluated.

The obtained ashing rate and its uniformity were extremely good at 6.7 μm / min ± 3.7%, and the surface charge density was 0.4 × 10 ¹¹ cm ^-2, which was a sufficiently low value, and the gate Dielectric breakdown was not observed either.

Example 2 Photoresist ashing was performed using the microwave plasma processing apparatus according to the second embodiment shown in FIG.

Interlayer SiO ₂ is used as the substrate 202 to be processed.
A silicon (Si) substrate (φ12 inch (about 30.5 cm)) was used immediately after the film was etched to form a via hole.

First, the substrate (Si substrate) 202 to be processed is placed on the substrate 203 to be processed, and then the temperature adjusting means 2 is used.
The heater is heated to 250 ° C. using a heater 04, and the inside of the plasma processing chamber 201 is evacuated through an exhaust system (not shown) to 10 ⁻⁵ Torr (about 1.33 × 10 ⁻³ Pa).
The pressure was reduced to. Oxygen gas is supplied through the plasma processing gas inlet 205 at a flow rate of 2 slm to the plasma processing chamber 201.
Introduced in.

Then, a conductance valve (not shown) provided in the exhaust system (not shown) is adjusted to adjust the processing chamber 2
The inside of 01 was maintained at ² Torr (about 2.67 × 10 ² Pa). In the plasma processing chamber 201, the endless annular waveguide 2
2. From the microwave power supply of 2.45 GHz via 18.
Power of 5 kW was supplied.

Thus, plasma was generated in the plasma processing chamber 201. At this time, the oxygen gas introduced through the plasma processing gas introduction port 205 is discharged from the plasma processing chamber 2
In 01, it was excited, decomposed, and reacted to become oxygen atoms, which were transported to the substrate (Si substrate) 202 to be processed, the photoresist on the substrate 202 to be processed was oxidized, and the photoresist was vaporized and removed. After ashing, gate insulation evaluation, ashing speed, substrate surface charge density, etc. were evaluated.

The obtained ashing rate and its uniformity were extremely good at 8.6 μm / min ± 4.8%, and the surface charge density was 1.2 × 10 ¹¹ cm ^-2, which was a sufficiently low value, and the gate Dielectric breakdown was not observed either.

Example 3 The microwave plasma processing apparatus according to the first embodiment shown in FIG. 1 was used to form a silicon nitride film for protecting a semiconductor element.

As the substrate 102 to be processed, a P-type single crystal silicon substrate with an inter-layer SiO ₂ film on which an Al wiring pattern (line and space 0.5 μm) was formed (plane orientation <100>, resistivity 10 Ω · cm). It was used. This P
The diameter of the mold single crystal silicon substrate is 300 mm.

First, the substrate to be processed (silicon substrate) 102.
After being placed on the substrate supporter 103 to be processed, the inside of the plasma processing chamber 101 was evacuated through an exhaust system (not shown), and a value of 10 ⁻⁷ Torr (about 1.33 × 10 ⁻⁵ Pa) was obtained. The pressure was reduced to.

Subsequently, the heater as the temperature adjusting means 104 was energized to heat the substrate 102 to be treated to 300 ° C., and the substrate 102 to be treated was kept at this temperature. Nitrogen gas was introduced into the processing chamber 101 through the plasma processing gas introduction port 105 at a flow rate of 600 sccm, and monosilane gas was introduced at a flow rate of 200 sccm.

Next, the conductance valve (not shown) provided in the exhaust system (not shown) is adjusted to adjust the processing chamber 1
The inside of 01 was maintained at 20 mTorr (about 2.67 Pa).

Then, a 2.45 GHz microwave power source (not shown) is used to 3.
Electric power of 0 kW was supplied into the plasma processing chamber 101.

Thus, plasma was generated in the plasma processing chamber 101. At this time, the nitrogen gas introduced through the plasma processing gas introduction port 105 is supplied to the plasma processing chamber 1
In 01, it is excited and decomposed into nitrogen atoms, which are transported toward the substrate (Si substrate) 102 to be processed and react with monosilane gas to form a silicon nitride film on the substrate 102 1.
It was formed with a thickness of 0 μm. After the film formation, the gate dielectric breakdown evaluation, film formation rate, film quality such as stress, etc. were evaluated. The stress changes the amount of warpage of the substrate before and after film formation by a laser interferometer
The product name was measured and determined.

The film formation rate and the uniformity of the obtained silicon nitride film were very good at 560 nm / min ± 2.6%, and the film quality was 0.8 × 10 ⁹ dyne · cm ⁻² (0.
8 × 10 ⁸ N ・ m ^-2 ) (compression), leak current 1.2 × 1
It was confirmed that the film had an extremely good quality of 0 ⁻¹⁰ A · cm ⁻² and a withstand voltage of 10.3 MV / cm, and no gate dielectric breakdown was observed.

Example 4 The microwave plasma processing apparatus according to the second embodiment shown in FIG. 3 was used to form a plastic lens antireflection silicon oxide film and a silicon nitride film.

The substrate 202 to be processed has a diameter of 50 mm.
A plastic convex lens was used.

First, after the substrate to be processed (lens) 202 is installed on the substrate to be processed substrate 203 to be processed, the inside of the plasma processing chamber 201 is evacuated via an exhaust system (not shown).
The pressure was reduced to a value of 0 ⁻⁷ Torr (about 1.33 × 10 ⁻⁵ Pa). Nitrogen gas was introduced into the processing chamber 201 at a flow rate of 150 sccm and monosilane gas at a flow rate of 70 sccm through the plasma processing gas introduction port 205.

Then, a conductance valve (not shown) provided in the exhaust system (not shown) is adjusted to adjust the process chamber 2
The inside of 01 was maintained at 5 mTorr (about 6.67 × 10 ⁻¹ Pa).

Then, a 2.45 GHz microwave power source (not shown) is used to connect the endless annular waveguide 218 to the 3.
Electric power of 0 kW was supplied into the plasma processing chamber 201.

Thus, plasma was generated in the plasma processing chamber 201. At this time, the nitrogen gas introduced through the plasma processing gas introduction port 205 is excited and decomposed in the plasma processing chamber 201 to become active species such as nitrogen atoms, and transported toward the substrate (lens) 202 to be processed. And reacts with monosilane gas to form a silicon nitride film on the substrate 2 to be treated.
It was formed on 02 in a thickness of 20 nm.

Next, oxygen gas was introduced into the processing chamber 201 at a flow rate of 200 sccm and monosilane gas at a flow rate of 100 sccm through the plasma processing gas introduction port 205. Then, a conductance valve (not shown) provided in the exhaust system (not shown) is adjusted to adjust the process chamber 20.
The inside of 1 was kept at 2 mTorr (about 2.67 × 10 ⁻¹ Pa).

Then, a 2.45 GHz microwave power source (not shown) 2.
Electric power of 0 kW was supplied into the plasma generation chamber 201.

Thus, plasma was generated in the plasma processing chamber 201. At this time, the oxygen gas introduced through the plasma processing gas introduction port 205 is excited and decomposed in the plasma processing chamber 201 to become active species such as oxygen atoms, and is directed toward the substrate (glass substrate) 202 to be processed. The silicon oxide film was transported and reacted with monosilane gas to form a silicon oxide film on the substrate 202 to be processed with a thickness of 85 nm. After film formation,
The gate dielectric breakdown evaluation, film formation rate, and reflection characteristics were evaluated.

The film formation rates and the uniformity of the obtained silicon nitride film and silicon oxide film were 370 nm / min ± 2.7% and 410 nm / min ± 2.8%, respectively, and the film quality was around 500 nm. It was confirmed that the reflectance was 0.17%, which was extremely good optical characteristics, and no gate dielectric breakdown was observed.

Example 5 The microwave plasma processing apparatus according to the first embodiment shown in FIG. 1 was used to form a silicon oxide film for semiconductor element interlayer insulation.

As the substrate 102 to be processed, Al is formed on the uppermost part.
A P-type single crystal silicon substrate (plane orientation <100>, resistivity 10 Ω · cm) on which a pattern (line and space 0.5 μm) was formed was used. The diameter of this P-type single crystal silicon substrate is 300 mm.

First, the substrate to be processed (silicon substrate) 102.
After being placed on the substrate support 103 to be processed, the inside of the plasma processing chamber 101 was evacuated through an exhaust system (not shown) to obtain a value of 10 ⁻⁷ Torr (about 1.33 × 10 ⁻⁵ Pa). The pressure was reduced to.

Subsequently, the heater as the temperature adjusting means 104 was energized to heat the substrate 102 to be treated to 300 ° C. and maintain the substrate 102 at this temperature. Oxygen gas was introduced into the processing chamber 101 through the plasma processing gas introduction port 105 at a flow rate of 400 sccm, and monosilane gas was introduced at a flow rate of 200 sccm.

Then, the conductance valve (not shown) provided in the exhaust system (not shown) was adjusted to maintain the inside of the plasma processing chamber 101 at 20 mTorr.

Next, 300 W of electric power is applied to the substrate support 102 through the high frequency applying means of 2 MHz, and 2.5 kW of electric power is supplied from the microwave power source of 2.45 GHz through the endless annular waveguide 118. It was supplied into the plasma processing chamber 101.

Thus, plasma was generated in the plasma processing chamber 101. The oxygen gas introduced through the plasma processing gas introduction port 105 is excited and decomposed in the plasma processing chamber 101 to become active species, which is transported toward the substrate (Si substrate) 102 to be processed and reacts with the monosilane gas, The silicon oxide film has a thickness of 0.8 μm on the substrate 102 to be processed.
Formed with a thickness of. At this time, the ion species are accelerated by the RF bias and enter the substrate to scrape the film on the pattern and improve the flatness.

After the treatment, the film forming rate, uniformity, withstand voltage, 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 the uniformity of the obtained silicon oxide film were as good as 310 nm / min ± 2.8%, and the film quality was a withstand voltage of 9.1 MV / cm, void-free, and was a good quality film. It was confirmed that no gate dielectric breakdown was observed.

Example 6 The microwave plasma processing apparatus according to the second embodiment shown in FIG. 3 was used to etch a semiconductor element interlayer SiO ₂ film.

As the substrate 202 to be processed, a P-type single crystal silicon substrate (plane orientation <100>, resistivity 10 Ω.multidot.m) having a 1 μm thick interlayer SiO ₂ film formed on an Al pattern (line and space 0.35 μm) was formed. cm) was used. The diameter of this P-type single crystal silicon substrate is 300 mm.

First, the substrate to be processed (silicon substrate) 202
Of the exhaust system (see FIG.
The inside of the etching chamber 201 is evacuated via (not shown),
10 ^-7Torr (about 1.33 × 10^-FiveReduced to the value of Pa)
Pressed. C through the plasma processing gas inlet 205
_FourF₈80 sccm, Ar 120 sccm, O₂4
Introduced into the plasma processing chamber 201 at a flow rate of 0 sccm
It was

Then, a conductance valve (not shown) provided in the exhaust system (not shown) is adjusted to move the inside of the plasma processing chamber 201 to 5 mTorr (about 6.67 × 10 ^-1 P
The pressure of a) was maintained.

Then, 280 W of electric power is applied to the substrate support 202 through the high frequency applying means of 2 MHz, and 3.0 kW of electric power is supplied from the 2.45 GHz microwave power source through the endless annular waveguide 218. It was supplied into the plasma processing chamber 201.

Thus, plasma was generated in the plasma processing chamber 201. The C ₄ F ₈ gas introduced through the plasma processing gas introduction port 205 is excited and decomposed in the plasma processing chamber 201 to become an active species, which is transported toward the substrate (silicon substrate) 202 to be processed and self-biased. The interlayer SiO ₂ film was etched by the ions accelerated by. The cooler 207 with an electrostatic chuck caused the substrate temperature to rise to only 30 ° C.

After etching, the gate dielectric breakdown evaluation, etching rate, selection ratio, and etching shape were evaluated. The etching shape was evaluated by observing the cross section of the etched silicon oxide film with a scanning electron microscope (SEM).

The etching rate and its uniformity, and the selectivity to polysilicon are 720 nm / min ± 2.4, respectively.
%, 20, the etching shape was almost vertical, the microloading effect was small, and no gate dielectric breakdown was observed.

Example 7 Using the microwave plasma processing apparatus according to the first embodiment shown in FIG. 1, the polysilicon film between semiconductor element gate electrodes was etched.

As the substrate 102 to be processed, a P-type single crystal silicon substrate having a polysilicon film formed on the top (plane orientation <100>, resistivity 10 Ω · cm) was used. The diameter of this P-type single crystal silicon substrate is 300 mm.

First, the substrate to be processed (silicon substrate) 102.
After being placed on the substrate supporter 103 to be processed, the inside of the plasma processing chamber 101 was evacuated through an exhaust system (not shown), and a value of 10 ⁻⁷ Torr (about 1.33 × 10 ⁻⁵ Pa) was obtained. The pressure was reduced to. CF ₄ gas was introduced into the plasma processing chamber 101 at a flow rate of 300 sccm and oxygen at a flow rate of 20 sccm through the plasma processing gas introduction port 105.

Then, a conductance valve (not shown) provided in the exhaust system (not shown) is adjusted to move the inside of the plasma processing chamber 101 to 2 mTorr (about 2.67 × 10 ^-1 P
The pressure of a) was maintained.

Next, high-frequency power of 300 W from a high-frequency power source (not shown) of 2 MHz is applied to the substrate support 103, and 2.
A power of 2.0 kW was supplied from the 45 GHz microwave power supply into the plasma processing chamber 101.

Thus, plasma was generated in the plasma processing chamber 101. The CF ₄ gas and oxygen introduced through the plasma processing gas introduction port 105 are excited and decomposed in the plasma processing chamber 101 into active species, which are transported toward the substrate (silicon substrate) 102 to be processed and self-biased. The polysilicon film was etched by the ions accelerated by. Due to the cooler 104 with an electrostatic chuck, the substrate temperature rose only to 30 ° C.

After the etching, the gate dielectric breakdown evaluation, the etching rate, the selection ratio, and the etching shape were evaluated. The etching shape was evaluated by observing the cross section of the etched polysilicon film with a scanning electron microscope (SEM).

The etching rate and its uniformity, and the selection ratio to SiO ₂ were 820 nm / min ± 2.9% and 2 respectively.
2, the etching shape was vertical, the microloading effect was small, and no gate dielectric breakdown was observed.

[0135]

As described above, according to the present invention,
Since the microwave introduction means is provided with the reflection limiting slot, the reflected power is limited and the discharge can be easily generated in a wide range of conditions.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing the structure of a microwave plasma processing apparatus according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram showing a plasma generation mechanism in a processing method using the microwave plasma processing apparatus according to the first embodiment of the present invention.

FIG. 3 is a schematic cross-sectional view showing the structure of a microwave plasma processing apparatus according to a second embodiment of the present invention.

FIG. 4 is a schematic cross-sectional view showing one embodiment of a method for manufacturing a structure in the order of steps.

FIG. 5 is a schematic cross-sectional view showing another embodiment of the method of manufacturing the structure in the order of steps.

FIG. 6A is a schematic cross-sectional view showing the structure of a conventional microwave plasma processing apparatus, and FIG. 6B shows a plasma generation mechanism in a processing method using the conventional microwave plasma processing apparatus. It is a schematic diagram.

[Explanation of symbols]

1; object to be processed 2, 7; insulating film 3; photoresist layer 3a; photoresist patterns 4, 5, 8; hole 6; line and space patterns 101, 201; plasma processing chambers 102, 202; substrate to be processed 103, 203; Supports 104 and 204; Substrate temperature adjusting means 105 and 205; Microwave plasma processing gas introducing means 106 and 206; Exhaust air 107 and 207; Dielectric windows 108 and 208; Microwave feeders with slots 110 and 210; Reflection limiting slots 111, 211; E branches 112, 212; standing waves 113, 213; slots 114, 214; surface waves 115, 215; surface standing waves 116, 216; surface plasmas 117, 217; bulk plasmas 118, 218. Endless annular waveguide 209; reflective surface

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 4K030 AA06 AA14 AA18 BA40 BA44                       CA04 CA07 FA01 KA30 KA46                 5F004 AA16 BA04 BB14 BB18 BB32                       DA00 DA01 DA23 DA26 DB02                       DB26 EB08                 5F045 AA09 AB33 AC01 AC15 AD07                       AE07 BB08 DP02 DQ10 EH03

Claims (12)

[Claims] 1. A plasma processing chamber, a target substrate mounting means for mounting a target substrate in the plasma processing chamber, and a dielectric material arranged to face the target substrate mounting means. A microwave plasma processing apparatus comprising: a window; and a microwave introducing unit that introduces a microwave into the plasma processing chamber by passing through the dielectric window, wherein the microwave introducing unit includes a waveguide and a microwave. A microwave plasma, comprising: a microwave introduction port introduced into the waveguide; and a reflection limiting slot provided at the microwave introduction port so that an incident wave power is twice or more a reflected wave power. Processing equipment. 2. The microwave plasma processing apparatus according to claim 1, wherein the microwave introducing unit has a flat plate-shaped multi-slot antenna using an endless annular waveguide. 3. The microwave plasma processing apparatus according to claim 1, wherein the waveguide constitutes a cavity resonator. 4. When n is a natural number, λ _{s is} the natural wavelength of the microwave, and ε _d is the dielectric constant of the dielectric window, the thickness of the dielectric window is approximately (2n−1) λ _s. -[Epsilon] _d ^{- 1} / 2/4, The microwave plasma processing apparatus according to any one of claims 1 to 3, wherein 5. A microwave reflecting means provided in the plasma processing chamber at a position separated from the surface of the dielectric window on the plasma processing chamber side by an odd multiple of ¼ of the natural wavelength of the microwave. The microwave plasma processing apparatus according to any one of claims 1 to 4, further comprising: 6. The distance between the surface of the dielectric window on the side of the plasma processing chamber and the target substrate mounting means is an odd multiple of 1/4 of the natural wavelength of the microwave. The microwave plasma processing apparatus according to claim 1. 7. A step of placing a substrate to be processed on a substrate to be processed placing means provided in a plasma processing chamber, a waveguide, a microwave inlet for introducing microwaves into the waveguide, and the microwave. By supplying the microwave power to the microwave introducing means having the reflection limiting slot provided so that the incident wave power is twice or more the reflected wave power at the wave introducing port, the microwave processing means is opposed to the substrate mounting means. And a microwave is introduced into the plasma processing chamber by passing through the dielectric window arranged as described above, and the microwave plasma processing method. 8. The microwave plasma processing method according to claim 7, wherein a film is formed on the substrate to be processed by a chemical vapor deposition method. 9. The microwave plasma processing method according to claim 7, wherein the substrate to be processed is subjected to etching processing. 10. The microwave plasma processing method according to claim 7, wherein the substrate to be processed is subjected to an ashing process. 11. The microwave plasma processing method according to claim 7, wherein the substrate to be processed is subjected to a doping process. 12. A method of manufacturing a structure, comprising the step of subjecting the substrate to be processed to microwave plasma processing by the microwave plasma processing method according to claim 7. .