JPH10158846A - Batch type microwave plasma processing apparatus and processing method - Google Patents

Abstract

(57) Abstract: A batch-type microwave plasma processing apparatus and a processing method capable of performing plasma processing with few defects at high throughput are provided. SOLUTION: The microwave plasma processing apparatus includes a processing chamber 101, substrate supporting means 103 for disposing a plurality of substrates in the processing chamber, and means for supplying microwaves into the processing chamber, wherein the microwave plasma processing apparatus includes: A batch type microwave plasma processing apparatus characterized in that the means for supplying the plasma is an endless annular waveguide 108 having a plurality of openings (slots 122); and a plasma processing method using the apparatus.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a batch type microwave plasma processing apparatus and a processing method. More specifically, the present invention relates to a batch-type microwave plasma processing apparatus and a plasma processing method capable of processing a large amount of substrates at high speed and with low defects by using plasma of high performance confined at high density. This plasma processing method is useful for forming a deposited film such as CVD, surface modification such as ashing and etching, and the like.

[0002]

2. Description of the Related Art CVD, sputtering, etching, ashing, cleaning, surface modification, and the like are known as plasma processing used in the manufacturing process of electronic parts such as semiconductor elements. In these steps, for example, a gas is introduced into a processing chamber of a plasma processing apparatus, and at the same time, power such as high frequency is supplied to generate plasma in the processing chamber, and the gas is excited, decomposed, and reacted to be distributed in the processing chamber. The surface of the substrate thus subjected is subjected to plasma treatment.

FIG. 3 is a schematic diagram showing an example of a conventional batch inductively coupled RF plasma processing apparatus. In FIG. 3, 3
01 is a plasma processing chamber, 302 is a plasma processing chamber 301
A plurality of substrates to be processed, 303 a support for the substrate 302, 304 a heater for heating the substrate 302, 305
Is a plasma processing gas introducing means, 306 is an exhaust port, 30
Reference numeral 7 denotes a dielectric constituting the plasma processing chamber 301, and reference numeral 308 denotes a high-frequency power supply coil.

[0004] Plasma generation and plasma processing using the plasma processing apparatus of FIG. 3 are performed, for example, as follows. The inside of the plasma processing chamber 301 is evacuated from the exhaust port 306 via an exhaust system (not shown). Subsequently, a plasma processing gas is introduced into the plasma processing chamber 301 at a predetermined flow rate via the gas introduction unit 305. Next, the exhaust port 3
06 conductance valve (not shown)
Is adjusted, and the inside of the plasma processing chamber 301 is maintained at a predetermined pressure. A desired power is supplied from a radio frequency (RF) power supply to the coil 30.
8, an induced magnetic field is generated parallel to the central axis of the coil 308. Furthermore, a vortex-like dielectric electric field is generated in the plasma processing chamber 301 by the induction magnetic field, and electrons are accelerated by the induction electric field to generate plasma. The plasma processing gas is excited, decomposed, and reacted by the generated plasma, and plasma-treats the surfaces of the plurality of substrates 302 mounted on the support 303.

The conventional batch-type inductively-coupled plasma processing apparatus as shown in FIG. 3 simultaneously processes a plurality of substrates 302, so that the throughput is high. However, there is a disadvantage that the surface of the base 302 is easily damaged by the plasma spread to the processing chamber 301. Further, the controllability of the process is also insufficient.

On the other hand, as a plasma processing apparatus that does not cause these problems, a single-wafer plasma processing apparatus that processes substrates one by one is known. In this apparatus, as an electromagnetic wave for supplying energy for generating plasma, there are a high frequency (RF), a microwave (MW), and the like.

FIG. 4 is a schematic diagram showing an example of a conventional single-wafer type capacitively coupled RF plasma processing apparatus. In FIG.
1 is a plasma processing chamber, 402 is a substrate to be processed disposed in the plasma processing chamber 401, 403 is a support of the substrate 402,
Reference numeral 404 denotes a heater for heating the base 402, reference numeral 405 denotes a plasma processing gas introducing unit, reference numeral 406 denotes an exhaust port, and reference numeral 408 denotes a high-frequency power supply plate electrode.

The generation and plasma processing of plasma using the single-wafer type capacitively coupled RF plasma processing apparatus shown in FIG. 4 are performed, for example, as follows. The inside of the plasma processing chamber 401 is evacuated from the exhaust port 406 via an exhaust system (not shown). Subsequently, the plasma processing gas is supplied to the gas introduction means 405.
Through the plasma processing chamber 401 at a predetermined flow rate. Next, a conductance valve (not shown) provided at the subsequent stage of the exhaust port 406 is adjusted, and the plasma processing chamber 401 is adjusted.
Is maintained at a predetermined pressure. By supplying desired power from the high-frequency power source to the plate electrode 408, a high-frequency electric field is generated perpendicular to the electrode 408, and the electric field accelerates electrons to generate plasma. The plasma processing gas is excited, decomposed, and reacted by the generated plasma, and performs plasma processing on the surface of the processing target substrate 402 mounted on the support 403.

In place of the RF plasma processing apparatus, a plasma processing apparatus using a microwave plasma down flow is also used. This is used for processes such as ashing and CVD of a gate insulating film, which dislike defects caused by the incidence of ions in plasma.

FIG. 5 is a schematic view showing an example of a conventional single-wafer microwave plasma processing apparatus. 5, reference numeral 501 denotes a plasma processing chamber; 502, a substrate to be processed disposed in the plasma processing chamber 501; 503, a support of the substrate 502;
Reference numeral 4 denotes a heater for heating the base 502, reference numeral 505 denotes a plasma processing gas introduction unit, reference numeral 506 denotes an exhaust port, and reference numeral 508 denotes a microwave power introduction resonator.

Generation of plasma and plasma processing using the plasma processing apparatus of FIG. 5 are performed, for example, as follows. The inside of the plasma processing chamber 501 is evacuated from the exhaust port 506 via an exhaust system (not shown). Subsequently, a plasma processing gas is introduced into the plasma processing chamber 501 at a predetermined flow rate via the gas introduction unit 505. Next, the exhaust port 5
06 conductance valve (not shown)
Is adjusted, and a predetermined pressure (0.
(Low pressure of about 01 to 3 Torr). By supplying desired power from a microwave power supply (not shown) via the resonator 508, electrons are accelerated by an electric field perpendicular to the direction in which the microwave travels to generate plasma. The plasma processing gas is excited, decomposed, and reacted by the generated plasma, and plasma-treats the surface of the substrate 502 placed on the support 503.

[0012]

When a single-wafer plasma processing apparatus as shown in FIG. 4 or FIG. 5 is used, plasma processing with few defects is possible. However, it is difficult to dramatically improve the throughput. On the other hand, the batch-type inductively coupled plasma processing apparatus as shown in FIG. 3 has high throughput as described above, but it is difficult to perform plasma processing with few defects, and process controllability is insufficient.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the conventional plasma processing apparatus, to reduce the number of defects, to improve the controllability of the process, and to realize a high-throughput batch type microwave plasma processing. An object of the present invention is to provide an apparatus and a processing method.

[0014]

SUMMARY OF THE INVENTION The present invention provides a microwave plasma processing apparatus having a processing chamber, a substrate supporting means for arranging a plurality of substrates in the processing chamber, and a means for supplying microwaves to the processing chamber. Wherein the means for supplying the microwave is an endless annular waveguide having a plurality of openings, wherein the batch type microwave plasma processing apparatus is provided.

Further, the present invention is a batch type microwave plasma processing method characterized in that a plurality of substrates are subjected to plasma processing using the above apparatus.

In the present invention, the use of an endless annular waveguide having a plurality of openings as the microwave supply means provides a high level of plasma confinement performance and generates high-density plasma with extremely few substrate incident ions. And thereby the object of the present invention can be achieved.

[0017]

Preferred embodiments of the present invention will be described below.

FIG. 1A is a schematic view showing an example of a microwave plasma processing apparatus according to the present invention, and FIG.
FIG. 2 is a schematic view showing a plasma generation mechanism of this apparatus, and FIG.
FIG. 2 is a sectional view taken along line AA of FIG.

In FIGS. 1A and 1B and FIG. 2, 101 is a plasma processing chamber, 102 is a substrate to be processed, and 103 is a substrate 10
2, a support for heating the substrate 102;
05 is a plasma processing gas introducing means, 106 is an exhaust port,
Reference numeral 107 denotes a dielectric that forms the plasma processing chamber 101;
Reference numeral 8 denotes an endless annular waveguide with a slot for introducing microwaves into the plasma processing chamber 101, 121 denotes a block for distributing microwaves to the left and right, 122 denotes slots, and 123 denotes an annular waveguide. Microwave, 124 is a microwave propagating in the annular waveguide 108, 125 is a leakage wave of the microwave introduced into the plasma processing chamber 101 through the slot 122 and the dielectric 107, and 126 is a dielectric wave passing through the slot 122 and the dielectric 107. The surface wave of the microwave propagating in the inside, 127 is the plasma generated by the leak wave,
128 is a plasma generated by the surface wave.

The generation and plasma processing of plasma using the microwave plasma processing apparatus of FIG. 1 are performed, for example, as follows. An exhaust port 106 is provided via an exhaust system (not shown).
Then, the inside of the plasma processing chamber 101 is evacuated. continue,
The plasma processing gas is introduced into the plasma processing chamber 101 at a predetermined flow rate through the gas introduction means 105. next,
By adjusting a conductance valve (not shown) provided in an exhaust system (not shown), the inside of the plasma processing chamber 101 is maintained at a predetermined pressure.

Then, desired power is supplied from a microwave power source (not shown) through the annular waveguide 108 to the plasma processing chamber 1.
When supplied into the plasma processing chamber 01, plasma is generated in the plasma processing chamber 101. That is, the microwave 123 introduced into the annular waveguide 108 is divided into two right and left by the distribution block 121 and propagates in the annular waveguide 108. Leakage waves 125 introduced into the plasma processing chamber 101 through the dielectric 107 from the slots 122 provided for every 又 は or の of the guide wavelength emit the plasma 12 near the slots 122.
7 is generated. Further, the microwave incident on the straight line perpendicular to the surface of the dielectric 107 at an angle equal to or greater than the Brewster angle is totally reflected on the surface of the dielectric 107 and propagates as a surface wave 126 on the surface of the dielectric 107. Adjacent slot 1
The surface waves 126 generated from the surface waves 12 interfere with each other, and the surface waves 12
A strong electric field, that is, an "antinode" is generated for every 1/2 wavelength of 6. The plasma 128 is also generated by the electric field exuding from the surface wave 126. At this time, if a gas is introduced into the processing chamber 101 from the plasma processing gas introducing means 105, the plasma processing gas is excited by the generated high-density plasma, and the plurality of plasma processing gases are placed on the support 103. The surface of the base 102 is subjected to plasma processing.

In the apparatus shown in FIGS. 1A and 1B and FIG. 2, at least a part of the inner wall of the processing chamber 101 is formed of a cylindrical dielectric 107 and has a plurality of openings (slots 122). An endless annular waveguide 108 is arranged so as to surround the cylindrical dielectric 107. And
This annular waveguide 108 has a cylindrical double wall structure of an inner wall and an outer wall, and has a configuration in which microwaves can propagate in a space between the inner wall and the outer wall. Further, a microwave introduction port is provided on the outer wall side, and the distribution block 121 described above is disposed near the microwave introduction port. The opening (slot 122) described above is provided on the inner wall. It is preferable that the slots 122 are provided every １ ／ or の of the guide wavelength, but the present invention is not limited to this. Note that the guide wavelength depends on the frequency of the microwave used and the cross-sectional dimension of the waveguide.

The shape of the annular waveguide 108 is not limited to such a cylindrical shape, but may be a desired shape according to the shape of the plasma generation chamber. For example, the shape may be a disk, a polygon, or the like.

In the present invention, the plasma processing chamber 101
It is desirable to perform plasma processing while maintaining the internal pressure of 0.1 Torr or more. Furthermore, 0.3 Torr to 10
Torr is preferred, and 1 Torr to 5 Torr is more preferred. When plasma is generated at a pressure of 0.1 Torr or more, the plasma is highly confined in the vicinity of the dielectric 107, and the tendency that the plasma does not exist in the vicinity of the base 102 is further increased. As a result, the energy of the ions incident on the substrate 102 becomes lower, and even in a batch type in which a plurality of substrates 102 are processed, plasma processing with fewer defects can be performed with high throughput.

Further, it is preferable that the end of the substrate 102 is arranged at least 20 mm away from the inner wall (the dielectric 107) of the processing chamber in order to prevent the influence of the plasma on the substrate 102.

In the present invention, the microwave frequency is set to 0.1.
It is preferable to appropriately select from the range of 8 GHz to 20 GHz. When microwaves are used as a gas excitation source, electrons can be accelerated by an electric field having a high frequency, gas molecules can be efficiently ionized and excited, the electron temperature is low, ion incident energy is low, and plasma is easily confined. There are advantages. Therefore, the microwave plasma processing apparatus has the effects of high gas ionization / excitation / decomposition efficiency, relatively easy formation of high-density plasma, and low-temperature, high-speed, low-defect processing. Further, 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 also an effect that highly clean plasma processing can be performed.

Dielectric 1 used to construct processing chamber
07 is SiO ₂ -based quartz, various glasses, Si ₃
N ₄ , NaCl, KCl, LiF, CaF ₂ , BaF ₂ ,
Inorganic substances such as Al ₂ O ₃ , AlN, MgO, polyethylene,
Films and sheets of organic substances such as polyester, polycarbonate, cellulose acetate, polypropylene, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyamide, and polyimide are applicable.

Further, the throughput can be further improved by connecting the transfer chamber for transferring the substrate to the processing chamber to the processing chamber via a gate valve and preheating the substrate. It is desirable that a desired substrate heating unit be provided inside the processing chamber and / or the substrate loading chamber.

Further, the apparatus can be provided with a magnetic field generating means so that a magnetic field can be applied to the substrate to perform plasma processing. As the magnetic field generating means, a coil or a permanent magnet can be used. When a coil is used, a cooling means such as a water cooling mechanism or air cooling may be used to prevent overheating.

Further, the apparatus is provided with an ultraviolet irradiation means, and the ultraviolet irradiation is performed on the surface of the substrate. Higher quality of processing can be achieved. As the light source, a light source that emits light that is absorbed by the substrate to be processed, the substrate attached to the substrate, or the reaction intermediate can be used. Examples of the light source include an excimer laser, an excimer lamp, a rare gas resonance line lamp, and a low-pressure mercury lamp. Appropriate.

(1) When the present invention is applied to deposition film formation The present invention can be applied to deposition film formation such as CVD. Specifically, by appropriately selecting the gas to be used, for example,
Si ₃ N ₄ , SiO ₂ , Ta ₂ O ₅ , TiO ₂ , TiN, Al
Insulating film such as ₂ O ₃ , AlN, MgF ₂ , a-Si, pol
semiconductor films such as y-Si, SiC, GaAs, Al, W,
Various deposited films such as metal films of Mo, Ti, Ta and the like can be efficiently formed.

The substrate to be processed may be any of conductive, electrically insulating or semiconductor. As the conductive substrate, Fe, Ni, Cr, Al, Mo, Au, Nb, T
metals such as a, V, Ti, Pt, Pb or alloys thereof;
Examples include brass and stainless steel. Examples of the insulating substrate include SiO ₂ -based quartz and various glasses, Si ₃ N ₄ ,
NaCl, KCl, LiF, CaF ₂ , BaF ₂ , Al ₂
Inorganic substances such as O ₃ , AlN, and MgO, polyethylene, polyester, polycarbonate, cellulose acetate,
Examples include films and sheets of organic substances such as polypropylene, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyamide, and polyimide.

As a gas for forming a deposited film, a generally known gas can be used. Gases that are easily decomposed by the action of plasma and can be deposited alone can be introduced into the plasma processing chamber by providing a film-forming gas introduction means near the substrate to achieve a stoichiometric composition and prevent film deposition in the plasma generation chamber. It is desirable to do. Further, it is desirable that a gas that is not easily decomposed by the action of plasma and that is difficult to deposit by itself is introduced into a plasma processing chamber by providing a plasma processing gas introducing means in a high-density region of plasma.

S such as a-Si, poly-Si, SiC, etc.
The source gas for forming the i-based semiconductor thin film is S
iH_Four, Si_TwoH₆ Inorganic silanes, such as tetraethylsila
(TES), Tetramethylsilane (TMS), Dimethyl
Organic silanes such as silane (DMS), SiF_Four, Si_Two
F₆, SiHF_Three, SiH_TwoF_Two, SiCl_Four, Si_TwoC
l ₆, SiHCl_Three, SiH_TwoCl_Two, SiH_ThreeCl, Si
Cl_TwoF_Two Such as halosilanes in a gaseous state at normal temperature and pressure
Certain or those that can be easily gasified. Ma
Also, as a gas introduced simultaneously with these source gases
Is H_Two, He, Ne, Ar, Kr, Xe, Rn, etc.
I can do it.

When forming a thin film of a Si compound such as Si ₃ N ₄ , SiO _2, etc., the source gas is SiH ₄ , Si ₂ H
Inorganic silanes such as ₆ , tetraethoxysilane (TEO)
S), organic silanes such as tetramethoxysilane (TMOS), octamethylcyclotetrasilane (OMCTS), SiF ₄ , Si ₂ F ₆ , SiHF ₃ , SiH ₂ F ₂ , Si
Cl ₄ , Si ₂ Cl ₆ , SiHCl ₃ , SiH ₂ Cl ₂ , Si
Halosilanes such as H ₃ Cl and SiCl ₂ F ₂ , and the like, which are in a gaseous state at normal temperature and normal pressure or can be easily gasified. The gases introduced simultaneously with these source gases include N ₂ , NH ₃ , N ₂ H ₄ , hexamethyldisilazane (HMDS), O ₂ , O ₃ , H ₂ O, NO, N ₂ O,
NO _{2 and the} like.

When forming a metal thin film of Al, W, Mo, Ti, Ta, or the like, the source gases are trimethyl aluminum (TMAl) and triethyl aluminum (TEA).
l), triisobutylaluminum (TIBAl), dimethylaluminum hydride (DMAIH), tungsten carbonyl (W (CO) ₆ ), molybdenum carbonyl (Mo (CO) ₆ ), trimethylgallium (TMG)
a), an organic metal such as triethylgallium (TEGa),
Examples include metal halides such as AlCl ₃ , WF ₆ , TiCl ₃ , and TaCl ₅ . The gases introduced simultaneously with these source gases include H ₂ , He, Ne, A
r, Kr, Xe, Rn and the like.

Al ₂ O ₃ , AlN, Ta ₂ O ₅ , TiO ₂ ,
As a source gas for forming a thin film of a metal compound such as TiN or WO ₃ , trimethyl aluminum (TMA) is used.
l), triethyl aluminum (TEAl), triisobutyl aluminum (TIBAl), dimethyl aluminum hydride (DMAIH), tungsten carbonyl (W (CO) ₆ ), molybdenum carbonyl (Mo (C
O) ₆ ), organic metals such as trimethylgallium (TMGa) and triethylgallium (TEGa), AlCl ₃ , W
Metal halides such as F ₆ , TiCl ₃ , TaCl _{5 and the} like can be mentioned. The gases introduced simultaneously with these source gases include O ₂ , O ₃ , H ₂ O, NO, N ₂ O, N
O ₂ , N ₂ , NH ₃ , N ₂ H ₄ , hexamethylene disilazane (HMDS) and the like can be mentioned.

(2) When the present invention is applied to surface modification: The present invention provides ashing, oxidized surface treatment, nitrided surface treatment,
It can be applied to surface modification such as doping, etching, and cleaning. Specifically, by appropriately selecting a gas to be used, for example, Si,
Using Al, Ti, Zn, Ta, etc., these substrates or surface layers are oxidized or nitrided, and B, A
Doping treatment of s, P, etc. is possible. As for cleaning, for example, cleaning of oxides, organic substances, heavy metals, and the like can be performed.

Oxidizing gases for ashing or oxidizing surface treatment of the substrate include O ₂ , O ₃ , H ₂ O, NO, N
₂ O, NO _{2 and the} like. In addition, when the substrate is subjected to nitriding surface treatment, the nitriding gas may be N ₂ , NH ₃ , N _2
2 H ₄ and hexamethyldisilazane (HMDS).

A place for cleaning organic substances on the substrate surface
In this case, the cleaning gas is O _Two, O_Three, H_TwoO,
NO, N_TwoO, NO_Two And the like. Also, the substrate surface
Cleaning gas when cleaning inorganic substances
As F_Two, CF_Four, CH_TwoF_Two, C_TwoF₆, CF_TwoC
l_Two, SF₆, NF_Three And the like.

[0041]

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

Example 1 Using the microwave plasma processing apparatus shown in FIG. 1, it was confirmed that plasma having good confinement performance was formed as follows.

A cylindrical quartz tube having a center diameter of 320 mm is used as the dielectric 107. The annular waveguide 108 has an inner wall section of 26 mm × 96 mm and a center diameter of 354 m.
m. The material of the annular waveguide 108 is made of stainless steel to maintain its mechanical strength, and its inner wall surface is coated with copper to suppress the propagation loss of microwaves, and is further subjected to silver-coated two-layer plating. did. Slots 122 for introducing microwaves into the plasma generation chamber 101 were formed in the annular waveguide 108. Slot 12
The shape of No. 2 was a rectangle having a length of 41 mm and a width of 3 mm, and was formed at intervals of 1/4 of the guide wavelength. The guide wavelength depends on the frequency of the microwave to be 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, it is about 159 mm. is there. In the annular waveguide 108 of this embodiment, 28 slots were formed at intervals of about 40 mm. Also, 4E
Tuner, directional coupler, isolator, 2.45GH
A microwave power supply (not shown) having a frequency of z was connected in order.

Using the microwave plasma processing apparatus shown in FIG. 1, the Ar flow rate was 500 sccm, and the pressure was 0.3 To.
Plasma was generated under the conditions of rr and microwave power of 3.0 kW. The obtained plasma was measured by the single probe method as follows. The voltage applied to the probe was changed in the range of -50 to +50 V, and the current flowing through the probe was measured by an IV measuring instrument. From the obtained IV curve, the electron density,
The electron temperature and the plasma potential were calculated. As a result, the electron density of the plasma near the quartz tube 107 is 1.2 × 10 ¹² / c
Although the density is high at m ³ , at a position 20 mm or more inside the quartz tube, it is 2.0 × 10 ⁸ / cm ³ , which is below the measurement limit of the probe used this time, and a plasma with extremely good confinement performance is formed. It was confirmed that it was.

In each of the following examples, the microwave plasma processing apparatus of this example was used unless otherwise specified.

Example 2 Ashing of a photoresist for ULSI was performed using the microwave plasma processing apparatus shown in FIG. 1 as follows.

As the substrate 102, a Si substrate (φ8 inch) with a 1.2 μm-thick photoresist (OFPR-800, manufactured by Tokyo Ohka Co., Ltd., hard-baked) was used. First, a carrier having five Si substrates 102 mounted thereon is placed on a substrate support 103 and heated to 200 ° C., and then the inside of the plasma processing chamber 101 is evacuated from an exhaust port 106 via an exhaust system (not shown). The pressure was reduced to 10 ^-4 Torr. Oxygen gas was introduced into the plasma processing chamber 101 through the plasma processing gas introduction pipe 105 at a flow rate of 500 sccm. Next, the conductance valve (not shown) provided in the exhaust system (not shown) is adjusted, and the plasma processing chamber 1 is adjusted.
01 was kept at 0.5 Torr. Plasma processing chamber 1
01 from the microwave power supply of 2.45 GHz to 3.0
kW of power was supplied through the annular waveguide 108. Thus, plasma was generated in the plasma processing chamber 101.
At this time, the oxygen gas introduced through the plasma processing gas introduction pipe 105 is excited and decomposed in the plasma processing chamber 101 to become active species such as oxygen atoms, and reacts with the photoresist on the Si substrate 102 to form carbon dioxide. A gas such as carbon was generated and the photoresist was removed. All the photoresist was removed in 23 seconds.

Ashing speed of the obtained photoresist
Is as large as 3.2 μm / min, and charged particles in the plasma
The charge density generated in / on the thermal oxide film is also 3.6 ×
10 ¹¹/ Cm^Two Was a sufficiently low value.

Example 3 Using the microwave plasma processing apparatus shown in FIG. 1, a silicon nitride film for a magneto-optical disk was formed as follows.

As the substrate 102, a polycarbonate (PC) substrate (φ3.5 inch) having a groove having a width of 1.2 μm was used. First, after a carrier having twelve PC substrates 102 mounted thereon was placed on the substrate support 103, the inside of the plasma processing chamber 101 was evacuated via an exhaust system (not shown) to reduce the pressure to 10 ^-6 Torr. The plasma processing chamber 1 was supplied with a nitrogen gas at a flow rate of 100 sccm and an argon gas at a flow rate of 600 sccm through the plasma processing gas introduction pipe 105.
01. At the same time, a monosilane gas was introduced into the plasma processing chamber 101 at a flow rate of 200 sccm via a film forming gas introducing means (not shown). Next, a conductance valve (not shown) provided in an exhaust system (not shown) is adjusted so that the inside of the plasma processing chamber 101 becomes 0.1 Torr.
r. 2.45 G in the plasma processing chamber 101
A power of 3.0 kW was supplied from the microwave power supply of Hz through the annular waveguide 103. Thus, plasma was generated in the plasma processing chamber 101. At this time, the nitrogen gas introduced through the plasma processing gas introduction pipe 105 is excited and decomposed into active species in the plasma processing chamber 101,
The silicon nitride film is transported in the direction of the silicon substrate 102 and reacts with the monosilane gas introduced through the film-forming gas introduction means, and a silicon nitride film is deposited on the silicon substrate 102 for 12 seconds.
It was formed with a thickness of 0 nm.

The deposition rate of the obtained silicon nitride film is 50
The film was extremely large at 0 nm / min, the film quality was 2.2, and it was confirmed that the film was a very good film having good adhesion and durability. Further, since the plasma was confined at a high density, an increase in the substrate temperature due to the incidence of ions was suppressed, and no deformation or the like of the substrate was observed.

Example 4 Using the microwave plasma processing apparatus shown in FIG. 1, a silicon oxide film and a silicon nitride film for preventing plastic lens reflection were formed as follows.

As the substrate 102, a plastic convex lens having a diameter of 50 mm was used. After a carrier having 21 lenses 102 mounted thereon was placed on the substrate support 103, the inside of the plasma processing chamber 101 was evacuated via an exhaust system (not shown) to reduce the pressure to 10 ^-6 Torr. 150 sc of nitrogen gas through the plasma processing gas introduction pipe 105
It was introduced into the plasma processing chamber 101 at a flow rate of cm. At the same time, a monosilane gas was introduced into the plasma processing chamber 101 at a flow rate of 100 sccm via a film formation gas introduction pipe (not shown). Next, a contactance valve (not shown) provided in an exhaust system (not shown) was adjusted to maintain the inside of the plasma processing chamber 101 at 0.5 Torr. Then, 2.4
A power of 3.0 kW from a microwave power supply (not shown) of 5 GHz is supplied to the plasma generation chamber 101 through the annular waveguide 108.
Supplied within. Thus, plasma was generated in the plasma generation chamber 101. At this time, the nitrogen gas introduced through the plasma processing gas introduction pipe 105 is excited and decomposed in the plasma processing chamber 101 to become active species such as nitrogen atoms, and is transported in the direction of the lens 102 to be formed. By reacting with the monosilane gas introduced through the gas introduction means, a silicon nitride film was formed on the lens 102 with a thickness of 21 nm.

Next, oxygen gas was introduced into the plasma processing chamber 101 through the plasma processing gas introducing pipe 105 at a flow rate of 200 sccm. At the same time, a monosilane gas was introduced into the plasma processing chamber 101 at a flow rate of 100 sccm through a gas introduction pipe for film formation. Next, the conductance valve (not shown) provided in the exhaust system (not shown) is adjusted,
The inside of the plasma processing chamber 101 was kept at 0.1 Torr.
Next, a power of 2.0 kW was supplied from a microwave power supply (not shown) of 2.45 GHz into the plasma processing chamber 101 via the annular waveguide 108. Thus, plasma was generated in the plasma processing chamber 101. At this time, the oxygen gas introduced through the plasma processing gas introduction pipe 105 is
It is excited and decomposed in the plasma processing chamber 101 to become active species such as oxygen atoms, is transported in the direction of the lens 102, reacts with the monosilane gas introduced through the film-forming gas introduction pipe, and forms the silicon oxide film on the lens 102. It was formed with a thickness of 86 nm on top.

The deposition 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 have a very good optical characteristic of a reflectance of about 0.3% at around 500 nm.

Embodiment 5 Using the microwave plasma processing apparatus shown in FIG. 1, a silicon nitride film for protecting a semiconductor element was formed as follows.

As the base 102, a P-type single crystal silicon substrate with an interlayer SiO ₂ film on which an Al wiring pattern (line and space 0.5 μm) was formed (plane orientation <10
0>, resistivity 10 Ωcm). First, a carrier on which five silicon substrates 102 are mounted is placed on a base support 103.
After being installed above, the inside of the plasma processing chamber 101 was evacuated via an exhaust system (not shown) to reduce the pressure to a value of 10 ^-6 Torr. Subsequently, a heater (not shown) was energized to heat the silicon substrate 102 to 300 ° C., and the substrate was kept at this temperature. Nitrogen gas was introduced into the plasma processing chamber 101 through the plasma processing gas introduction tube 105 at a flow rate of 500 sccm. At the same time, a monosilane gas was introduced into the plasma processing chamber 101 at a flow rate of 100 sccm via a film forming gas introducing means (not shown). Next, an exhaust system (not shown)
The conductance valve (not shown) provided in the plasma processing chamber 101 was adjusted to maintain the inside of the plasma processing chamber 101 at 0.01 Torr. Next, power of 3.0 kW was supplied from a microwave power supply (not shown) of 2.45 GHz via the annular waveguide 108. Thus, plasma was generated in the plasma processing chamber 101. At this time, the plasma processing gas inlet 10
Nitrogen gas introduced through the plasma processing chamber 101
Is excited and decomposed into active species in the silicon substrate 10
The silicon nitride film was transported in the direction of No. 2 and reacted with the monosilane gas introduced through the film-forming gas introduction means, so that a silicon nitride film was formed on the silicon substrate 102 to a thickness of 1.0 μm.

The deposition rate of the obtained silicon nitride film is 46
Extremely large at 0 nm / min, and film quality is 1.1 × 1
0 ⁹ dyn / cm ² (compression), leak current 1.2 × 10
It was confirmed that the film was a very good film having a ^-10 A / cm ² and a withstand voltage of 9 MV / cm. In addition, this 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).
Was measured and determined.

<Embodiment 6> Using the microwave plasma processing apparatus shown in FIG.
The isotropic etching of the iN film was performed.

As the substrate 102, a P-type single crystal silicon substrate (plane orientation <100>, resistivity 10 Ωcm) having a 1 μm thick BPSG film formed on a polysilicon pattern (line and space 0.5 μm) was used. . First,
After a carrier having five silicon substrates 102 mounted thereon was placed on the substrate support 103, the inside of the plasma processing chamber 101 was evacuated via an exhaust system (not shown) to reduce the pressure to 10 ^-6 Torr. CF ₄ was introduced into the plasma processing chamber 101 through the plasma processing gas introduction pipe 105 at a flow rate of 300 sccm. Next, a conductance valve (not shown) provided in an exhaust system (not shown) was adjusted to maintain the inside of the plasma processing chamber 101 at 0.1 Torr.
1.5 kW of electric power was supplied from a 2.45 GHz microwave power supply into the plasma generation chamber 101 via the annular waveguide 103. Thus, plasma was generated in the plasma generation chamber 101. The CF ₄ gas introduced via the plasma processing gas introduction pipe 105 was excited and decomposed in the plasma processing chamber 101 to become active species, was transported in the direction of the silicon substrate 102, and the SiN film was etched.

The etching rate was as good as 300 nm / min. The etching selectivity and the etching shape were also good. The etched shape was evaluated by observing the cross section of the etched silicon nitride film with a scanning electron microscope (SEM).

Example 7 Using the microwave plasma processing apparatus shown in FIG. 1, a silicon oxide film for semiconductor device gate insulation was formed as follows.

As the base 102, a P-type single crystal silicon substrate (plane orientation <100>, resistivity 10 Ωcm) was used. After installing a carrier on which five silicon substrates 102 are mounted on the substrate support 103, the inside of the plasma processing chamber 101 is evacuated via an exhaust system (not shown) to 10 ^-6 Torr.
The pressure was reduced to the value of r. Subsequently, power was supplied to a heater (not shown) to heat the silicon substrate 102 to 300 ° C., and the silicon substrate 102 was maintained at this temperature. Oxygen gas was introduced into the plasma processing chamber 201 through the plasma processing gas introduction pipe 105 at a flow rate of 200 sccm. At the same time, monosilane gas is supplied through a film forming gas introducing means (not shown).
It was introduced into the plasma processing chamber 101 at a flow rate of 0 sccm. Next, the conductance valve (not shown) provided in the exhaust system (not shown) is adjusted, and the plasma processing chamber 101 is adjusted.
Was maintained at 0.2 mTorr. Then 2.45G
An electric power of 1.5 kW was supplied from the microwave power supply of 1 Hz into the plasma processing chamber 101 through the annular waveguide 108.
Thus, plasma was generated in the plasma processing chamber 101. At this time, the oxygen gas introduced through the plasma processing gas inlet 105 is excited and decomposed in the plasma processing chamber 101 to become active species such as oxygen atoms, and is transported in the direction of the silicon substrate 102 to form a film. Reacted with the monosilane gas introduced through the use gas introduction means, a silicon oxide film was formed on the silicon substrate 102 to a thickness of 0.1 μm.

The film formation rate and uniformity of the obtained silicon oxide film were as good as 120 nm / min ± 2.2%, the film quality was 5 × 10 ⁻¹¹ A / cm ² , the withstand voltage was 10 MV / min.
cm, and the interface state density was 5 × 10 ¹⁰ cm ⁻² , and it was confirmed that the film was an extremely good film. The interface state density was determined from a CV curve obtained by applying a high frequency of 1 MHz obtained by a capacitance measuring device.

Example 8 Using the microwave plasma processing apparatus shown in FIG. 1, a silicon oxide film for a semiconductor element interlayer insulating film was formed as follows.

As the substrate 102, a P having an Al pattern (line and space 0.5 μm) formed on the uppermost portion was used.
Type single crystal silicon substrate (plane orientation <100>, resistivity 10
Ωcm). First, after a carrier on which five silicon substrates 102 are mounted is placed on the substrate support 103,
The inside of the plasma processing chamber 101 was evacuated through an exhaust system (not shown) to reduce the pressure to a value of 10 ^-6 Torr. Subsequently, the heater 104 is energized and the silicon substrate 102 is heated to 300 ° C.
And the substrate was kept at this temperature. Oxygen gas was introduced into the plasma processing chamber 101 through the plasma processing gas introduction pipe 105 at a flow rate of 500 sccm. At the same time, a tetraethoxysilane (TEOS) gas was introduced into the plasma processing chamber 101 at a flow rate of 200 sccm from a film forming gas introducing means (not shown). Next, the conductance valve (not shown) provided in the exhaust system (not shown) is adjusted,
The inside of the plasma processing chamber 101 was maintained at 0.3 Torr.
Next, 1.5 kW from a microwave power supply of 2.45 GHz
Is supplied to the plasma processing chamber 10 through the annular waveguide 108.
1. Thus, plasma was generated in the plasma processing chamber 101. Gas inlet tube 105 for plasma processing
The oxygen gas introduced through the plasma processing chamber 101 becomes active species that are excited and decomposed in the plasma processing chamber 101, and the silicon substrate 102
And reacted with the tetraethoxysilane gas introduced through the film-forming gas introduction means to form a silicon oxide film on the silicon substrate 102 with a thickness of 0.8 μm.

The obtained silicon oxide film had a good film formation rate and uniformity of 190 nm / min ± 2.5%, and the film quality was confirmed to be a good film with a dielectric strength of 9.5 MV / cm. The cover factor showing the step coverage was 0.9, and the gas confinement of TEOS was suppressed by plasma confinement, indicating a good shape. The step coverage was A
The cross section of the silicon oxide film formed on the l wiring pattern was observed with a scanning electron microscope (SEM), and the ratio (cover factor) of the film thickness on the step side wall to the film thickness on the step was obtained and evaluated.

[0068]

According to the present invention described above, high confinement performance can be obtained around the plasma processing chamber, high-density plasma with very few substrate incident ions can be generated, and plasma processing with few defects can be performed by controlling the process. And can be performed with high throughput.

The present invention relates to batch-type plasma processing for processing a plurality of substrates at once, and is very useful for various processing techniques such as formation of a deposited film such as CVD, surface modification such as ashing and etching, and the like.

[Brief description of the drawings]

FIG. 1A is a schematic diagram illustrating an example of a microwave plasma processing apparatus according to the present invention, and FIG. 1B is a schematic diagram illustrating a plasma generation mechanism of the apparatus.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a schematic view showing a conventional batch type inductively coupled RF plasma processing apparatus.

FIG. 4 is a schematic diagram showing a conventional single-wafer type capacitively coupled RF plasma processing apparatus.

FIG. 5 is a schematic view showing a conventional single-wafer microwave plasma processing apparatus.

[Explanation of symbols]

101, 301, 401, 501 Plasma processing chamber 102, 302, 402, 502 Substrate 103, 303, 403, 503 Substrate support 104, 304, 404, 504 Heater 105, 305, 405, 505 Plasma processing gas introducing means 106 , 306, 406, 506 Exhaust port 107, 307 Dielectric 108 Endless annular waveguide 308 Inductively coupled coil 408 Capacitively coupled electrode 508 Microwave resonator 121 Block for distributing microwaves left and right 122 Slot 123 Ring waveguide Microwave introduced into tube 124 Microwave propagating in annular waveguide 125 Leakage wave 126 Surface wave 127 Plasma generated by leakage wave 128 Plasma generated by surface wave

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI H01L 21/027 H01L 21/30 572A

Claims (11)

[Claims] 1. A microwave plasma processing apparatus comprising: a processing chamber; substrate support means for arranging a plurality of substrates in the processing chamber; and means for supplying microwaves into the processing chamber. A batch type microwave plasma processing apparatus, wherein the supply means is an endless annular waveguide having a plurality of openings. 2. The process chamber according to claim 1, wherein at least a part of an inner wall of the processing chamber is formed of a cylindrical dielectric, and the endless annular waveguide is disposed so as to surround the cylindrical dielectric. Batch type microwave plasma processing equipment. 3. The batch type microwave plasma processing apparatus according to claim 1, wherein said substrate support means is means for disposing end portions of said plurality of substrates at least 20 mm from an inner wall of said processing chamber. 4. A batch-type microwave plasma processing method, wherein a plurality of substrates are subjected to plasma processing using the processing apparatus according to claim 1. 5. A method in which a plurality of substrates are placed in a processing chamber, the processing chamber is evacuated, and a plasma processing gas is introduced into the processing chamber to maintain the internal pressure at 0.1 Torr or more. 5. The batch-type microwave plasma processing method according to claim 4, wherein microwaves are introduced by an annular waveguide, plasma is generated in the processing chamber, and the plurality of substrates are subjected to plasma processing. 6. The batch type microwave plasma processing method according to claim 4, wherein the end portions of the plurality of substrates are arranged at least 20 mm apart from the inner wall of the processing chamber. 7. A method for forming a deposited film, comprising the step of performing the batch type microwave plasma processing method according to claim 4, 5 or 6. 8. The method according to claim 7, wherein the plasma processing method is performed for CVD. 9. A surface modification method comprising the step of performing the batch type microwave plasma treatment method according to claim 4, 5 or 6. 10. The surface modification method according to claim 9, wherein the plasma processing method is performed for ashing. 11. The method according to claim 9, wherein the plasma processing method is performed for etching.