JP3327618B2 - Plasma processing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to the use of plasma
The present invention relates to a plasma processing apparatus for depositing a film on a substrate, etching a film on the substrate, and modifying a film on the substrate. The plasma processing apparatus of the present invention activates a gas with plasma, for example, and uses the gas to use various films (insulator film, protective film, semiconductor film, etc.) used for sensors, optical components, acoustic products, semiconductor devices, and the like. Film, metal film, etc.), etching these films, performing surface cleaning and surface modification of the workpiece, and performing surface hardening treatment of cutting tools and cutting tools. Involved.

[0002]

2. Description of the Related Art Gas is activated by discharge plasma,
The method of depositing the target substance on the substrate surface using this active species to make it thinner, or performing processing such as etching or surface modification, requires that the processing be possible at low temperatures, and that processing that is not possible in the past is possible. In recent years, it has made rapid progress because of its advantages. The active species refers to a free species (radical), an excited species, an electron, an ion, or a mixture thereof. The present invention particularly relates to a treatment method using a neutral active species. Neutral active species refer to electrically neutral free and excited species. Free species refers to active atoms or molecules released from the original stable molecule and is in principle in the ground state. Excited species are those that have been activated by the transition of an atom or molecule from the ground state to the excited state.

In the fields of sensors and optical components, particularly semiconductor devices, a large-area, uniform and high-speed surface treatment is required. Therefore, there is a demand for an apparatus capable of producing a large-area uniform high-density plasma and performing surface treatment while controlling active species. On the other hand, in the surface treatment for hardening a blade, a cutting tool, and the like, there is a need to produce a diamond-like film and a BN film at a high speed. For this reason, it has been desired to develop a device that performs high-speed surface treatment by installing a substrate in a place where the concentration of active species is high.

[0004] As an invention realizing such a high-speed and high-quality surface treatment process, Japanese Patent Publication No. Hei 4-71575,
JP-A-62-227089 and JP-A-63-1
There is one described in US Pat. These inventions have been filed by the applicant of the present invention, and as described in the specification thereof, extremely high quality surface treatment can be performed. Among them, the plasma processing apparatus described in Japanese Patent Publication No. 4-71575 is disclosed in J. Vac. Sci. Techno.
l. As described in A4 (3) (1986), pp. 475-479, it is important as a thin film production apparatus for semiconductor devices.
In the specifications of the three publications, "LTE plasma"
The term comes out, which is the same as the "high-temperature non-equilibrium plasma" in this specification.

In recent years, for example, in the production of semiconductor devices, the wafer size has become much larger. In addition, there is a demand for a larger display in the display field. Since the surface area to be subjected to the surface treatment has been widened as described above, and high-speed surface treatment is also required for these, there is a need for a high-density plasma production technique which is more uniform and can handle a large area.

As a technique for performing a large-area and uniform surface treatment, a technique using a multi-cusp magnetic field is known. For example, a multi-cusp magnetic field is formed in the plasma generation chamber, and a multi-cusp magnetic field is formed in the path from the plasma generation chamber to the processing chamber or in the processing chamber itself (for example, Japanese Patent Application Laid-Open No. 63-19222).
9, JP-A-2-17636, JP-A-2-176
No. 22532).

[0007]

It is known from the above-mentioned Japanese Patent Publication No. 4-71575 or the like to generate a large amount of active species using high-temperature non-equilibrium plasma and to process a substrate using the active species. It is also known from the above-mentioned Japanese Patent Application Laid-Open No. 63-192229 to uniformly treat a large-area substrate by uniformly confining plasma using a multi-cusp magnetic field. However, in a conventional plasma processing apparatus using a multi-cusp magnetic field, the plasma is uniformly confined using the multi-cusp magnetic field, and the substrate is processed using charged particles such as electrons and ions inside the plasma. On the other hand, there is a demand for an apparatus for realizing high-speed and large-area processing for substrate processing using neutral active species.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a plasma processing apparatus capable of performing a high-speed and large-area substrate processing using neutral active species.

[0009]

The first aspect of the present invention provides
A plasma generation chamber for generating neutral active species, a processing chamber disposed adjacent to the plasma generation chamber, a substrate holder installed in the processing chamber to hold a substrate to be processed, and a plasma generation chamber and a processing chamber. Oite an exhaust mechanism for exhausting the vacuum, the plasma treatment equipment and a gas introduction mechanism for introducing at least one of the processing chamber and the plasma generating chamber a gas necessary for the surface treatment of the substrate to be processed, the processing chamber Multi cusp magnet
And the inner wall of the processing chamber
Walls other than near the cusp of the cusp magnetic field are reflected by neutral active species
And the material of this neutral active species reflecting member
It is different from the material of the material. In this specification, the term “substrate” refers to an object on which plasma processing is performed, and is not limited to a thin plate, but includes any shape.

In this plasma processing apparatus , first, a large amount of neutral active species can be generated by using high-temperature non-equilibrium plasma as compared with ordinary plasma. Then, the neutral active species is guided to a processing chamber in which a multi-cusp magnetic field is formed, and the substrate is processed. By the way, the multi-cusp magnetic field affects the movement of the charged particles, but does not directly affect the behavior of the neutral active species. In the present invention, a multi-cusp magnetic field is used to keep the plasma in the processing chamber away from the inner wall surface of the processing chamber. Since the present invention actively utilizes neutral active species for substrate processing, it is important that a large amount of neutral active species generated by high-temperature non-equilibrium plasma is not wasted in the processing chamber. . Since neutral active species are electrically neutral, they cannot be confined near the center of the processing chamber depending on the magnetic field. Therefore, the neutral active species frequently collides with the inner wall surface of the processing chamber particularly in a low pressure region. When a neutral active species collides with the inner wall surface of the processing chamber, the activated state is lost depending on the material of the inner wall surface. Therefore, it is desirable that the material of the inner wall surface of the processing chamber be devised so that even if the neutral active species collides, the neutral active species returns to the inside of the processing chamber while remaining as active as possible. However, when the inner wall surface of the processing chamber is exposed to the plasma, the range of choice of the material of the inner wall surface is limited, and it becomes impossible to use an effective neutral active species reflecting member. Therefore, in the present invention, the plasma in the processing chamber is separated from the inner wall surface of the processing chamber by using a multi-cusp magnetic field, whereby the optimum neutral active species reflecting member can be selected.

The multi-cusp magnetic field according to the present invention may be a linear cusp magnetic field or a ring cusp magnetic field.
Alternatively, a combination of both may be used, and any cusp magnetic field can be used.

The meaning of high-temperature non-equilibrium plasma in the present invention is the same as "LTE plasma" described in Japanese Patent Publication No. 4-72575 filed by the present applicant. As described in this publication, high-temperature non-equilibrium plasma can generate a larger amount of active species than ordinary glow discharge plasma, and contains a large amount of neutral active species. In the present invention, this large amount of neutral active species is positively utilized for substrate processing. By the way, this invention
This does not preclude electrons and ions other than the neutral active species from participating in the substrate processing.As long as the neutral active species plays an important role in the substrate processing, other charged particles participate in the substrate processing. It does not matter.

[0013]

[0014]

According to the present invention, the inner wall surface of the processing chamber is covered with a neutral active species reflecting member, whereby the neutral active species is reflected by the neutral active species reflecting member while being kept as active as possible. , Preventing a decrease in neutral active species. The multi-cusp magnetic field prevents the plasma inside the processing chamber from approaching the wall of the processing chamber, thereby exposing the neutral active species reflecting member to the plasma and damaging the neutral active species reflecting member. This prevents substances that are inconvenient for substrate processing from scattering into the processing chamber. Since the plasma in the processing chamber can approach the inner wall surface of the processing chamber near the cusp of the multi-cusp magnetic field, it is better not to dispose the neutral active species reflecting member near this cusp. The neutral active species reflecting member may be coated on the inner wall surface of the processing chamber, or a member separate from the processing chamber may be arranged close to the inner wall surface of the processing chamber.

When the neutral active species collides with the metal wall, it is hardly expected that the neutral active species reflects while maintaining the active state. Therefore, the inner wall surface of the processing chamber should be covered with a material other than metal. Is desirable. Therefore, the second invention uses any one of an oxide, a fluororesin, and a silicon compound as a material of the neutral active species reflection member in the first invention. As the oxide, quartz glass or alumina (Al
₂ O ₃ ) or Pyrex (registered trademark) glass can be used. As the fluororesin, polytetrafluoroethylene is most preferable because of its excellent chemical stability and high-temperature stability. SiN or SiC can be used as the silicon compound. The material of the neutral active species reflection member is preferably selected according to the type of neutral active species used.

[0017]

FIG. 1 is a front sectional view of an example of a plasma processing apparatus according to the present invention. This plasma processing apparatus mainly
A processing chamber 3, a substrate holder 2 therein, a potential control mechanism 30 for controlling the potential of the substrate holder 2,
An exhaust mechanism 40, a high-temperature non-equilibrium plasma generating mechanism 50,
A first gas introduction mechanism 70 and a second gas introduction mechanism 80,
And a multi-cusp magnetic field generating mechanism 90.
Hereinafter, the structure of each part will be described in detail.

A substrate holder 2 is provided in the processing chamber 3, and a substrate 1 to be subjected to a surface treatment is held on the substrate holder 2. The processing chamber 3 is made of austenitic stainless steel.
It has an inner diameter of about 45 cm and a height of 30 cm. The diameter of the substrate holder-2 is about 30 cm.

The substrate holder 2 is provided with a temperature adjusting mechanism 20. The thermocouple 21 measures the temperature of the substrate holder 2. The substrate holder 2 is heated by the heater 22 and cooled by a cooling medium flowing in the cooling pipe 23. As the cooling medium, gas such as compressed air or He, or water is used. Based on the temperature of the substrate holder-2 measured by the thermocouple 21, the power supply to the heater 22 and the temperature and supply amount of the cooling medium in the cooling pipe 23 are adjusted by a temperature controller (not shown). The target substrate temperature can be set.

The substrate holder 2 is provided with a potential control mechanism 30 for controlling the potential of the substrate. There is an insulator 31 between the substrate holder-2 and the processing chamber 3,
Both are electrically insulated. High frequency power is applied to the substrate holder 2 from a high frequency power supply 33 through a capacitor 32. For example, a high frequency of 13.562 MHz is adjusted to a power of 1500 W and applied to the substrate holder-2. The capacitor 32 matches the impedance when a high frequency is applied. When a T-type circuit generally known as a matching circuit is used, such a capacitor 32 is inevitably formed. This capacitor 32 is provided with a self-bias (direct-current bias) of the substrate 1 caused by application of high-frequency power. Component) is prevented from being grounded. This self-bias is generally a negative direct current component, whereby the active species having a positive charge in the processing chamber 3 are accelerated toward the substrate 1. It is also possible to use a high-frequency power supply with a frequency on the order of kHz. In this case, positive charges can be moved not only by the self-bias component but also by a high-frequency electric field, and irradiation of active species can be arbitrarily selected. Becomes possible.
Further, a DC power supply or 50
A commercial frequency power supply of ６０60 Hz can also be used. In this case, the capacitor 32 will be removed.

Next, the exhaust mechanism 40 will be described. The gas in the processing chamber 3 is exhausted by a turbo molecular pump 42 through a main valve 41. The oil rotary pump 43 is for performing differential evacuation of the turbo molecular pump 42. When it is necessary to precisely control the pressure in the processing chamber 3, it is effective to install a variable conductance valve (not shown) between the main valve 41 and the turbo molecular pump 42. The pressure in the processing chamber 3 can be kept constant by changing the conductance of the variable conductance valve based on a signal from a pressure gauge (not shown) provided in the processing chamber 3. Further, in order to evacuate the processing chamber 3 from the atmospheric pressure to the operable pressure of the turbo molecular pump 42 (about 1 Torr) as in the case of substrate exchange, a rough exhaust system (not shown) is required. It is effective to use a root pump and an oil rotary pump together in the roughing exhaust system.

Next, the high-temperature non-equilibrium plasma generating mechanism 50 will be described. The plasma generation chamber is made of quartz glass (SiO
₂ ). This discharge tube 51
It is a double tube made of quartz glass, between which water is cooled for cooling. Thereby, the discharge tube 5 by plasma heating
1 is prevented from dissolving. When fluorine radicals are present in the plasma generation chamber, the higher the temperature of the discharge tube 51, the more the etching rate of the quartz glass by the fluorine radicals increases, and the greater the damage of the quartz glass.
The cooling means described above is also effective in preventing this.

A coil-shaped antenna 52 is arranged around the discharge tube 51. The alternating power generated from the high frequency power supply 53 is supplied to the antenna 52 through a matching circuit (not shown).
Is applied to When a gas is introduced into the plasma generation chamber and the above-described alternating power and the inner diameter of the discharge tube 51 satisfy predetermined conditions, a high-temperature non-equilibrium plasma 60 is generated. Switch 5
4 is for selecting the direction of grounding of the antenna 52. Note that both ends of the antenna 52 may be at a floating potential, or an upper end or a lower end may be grounded.

The method of producing the high-temperature non-equilibrium plasma 60 and the apparatus configuration thereof are described in Japanese Patent Publication No.
No. 75, JP-A-62-227089 and JP-A-63-166971. Note that the term LTE plasma described in these three publications refers to the same high-temperature non-equilibrium plasma in this specification. In the present specification, “LTE
The term "high-temperature non-equilibrium plasma" is more appropriate than the term "plasma" because it reflects the actual state of plasma.

Next, the gas introduction mechanism will be described. This embodiment includes a first gas introduction mechanism 70 and a second gas introduction mechanism 80. In the first gas introduction mechanism 70,
The first gas passes through a pressure reducing valve from a gas cylinder (not shown), and is flow-controlled by a flow controller.
1 is introduced into the discharge tube 51 from the direction of the arrow 72. The first gas is activated by the high-temperature non-equilibrium plasma 60, thereby generating a high concentration of active species 4, and among these active species, mainly neutral active species are used for the intended surface treatment.

In the second gas introduction mechanism 80, the second gas passes through a pressure reducing valve from a gas cylinder (not shown), is flow-controlled by a flow controller, and enters the processing chamber 3 through a valve 81 in the direction of arrow 82. be introduced. The second gas is introduced into the processing chamber 3 through a number of small holes 84 provided in a donut-shaped gas blowing ring 83.

With only the second gas, the high-temperature non-equilibrium plasma 6
If argon or the like is used as the first gas when 0 becomes unstable, the high-temperature non-equilibrium plasma 60 can be stabilized, and high-quality surface treatment with good controllability can be performed.

Next, the multi-cusp magnetic field generating mechanism 90 will be described. FIG. 2A is a sectional view taken along line AA of FIG. A multi-cusp magnetic field 93 is formed by arranging a large number of magnets 91 around the outer wall of the processing chamber 3. Each magnet 91 extends vertically in a long direction (see FIG. 1), and a linear multi-cusp magnetic field 9 is provided inside the processing chamber.
3 is formed. As the magnet 91, a strong magnet such as a samarium-cobalt magnet is preferably small and densely arranged. The magnetic pole surface opposite to the processing chamber 3 is fixed to a pole piece 92 made of ferritic stainless steel, so that a magnetic field can be generated more effectively.

FIG. 2B is an enlarged plan sectional view of the vicinity of the wall surface of the processing chamber. The inner wall surface of the processing chamber 3 is covered with a neutral active species reflecting member 94. This neutral active species reflection member 94
Is not present near the cusp 95 of the multi-cusp magnetic field, but is installed only at a position distant from the cusp 95. In this embodiment, the neutral active species reflecting member 94 is made of polytetrafluoroethylene. This neutral active species reflection member 94
Is coated on the inner wall surface of the processing chamber 3. Due to the presence of the multi-cusp magnetic field 93, the plasma in the processing chamber 3 is confined near the center of the processing chamber 3, and the plasma does not touch the neutral active species reflecting member 94. Also, cusp 95
In the vicinity, the plasma can approach the wall surface. However, since the neutral active species reflecting member 94 does not exist in this portion, the neutral active species reflecting member 94 is not exposed to the plasma. Therefore, the neutral active species reflection member 94 is not damaged, and substances that are inconvenient for substrate processing are not scattered in the processing chamber. The neutral active species collides with the neutral active species reflecting member 94 without being confined in the multi-cusp magnetic field 93, but the neutral active species is reflected by the neutral active species reflecting member 94 to maintain the active state. It is possible to return to the inside of the processing chamber as it is. If the neutral active species reflecting member 94 does not exist, the neutral active species collides with the inner wall surface of the stainless steel, and the activity is lost.

In the example of FIG. 2A, the pole piece 92 is formed in an annular shape, but in the example of FIG.
The pole piece 92b is divided so as to connect only a pair of adjacent magnets 91. In the latter case, since the outer wall of the processing chamber 3 can be approached from between the pole pieces 92 b, a viewing window and various ports can be provided between the magnets 91.

Next, an example in which the apparatus shown in FIGS. 1 and 2 is applied to an actual surface treatment process will be described. In FIG.
200 sc of oxygen gas through the first gas introduction mechanism 70
Flow at a flow rate of cm. Further, the silane gas flows at a flow rate of 100 sccm through the second gas introduction mechanism 80. The pressure in the processing chamber 3 is maintained at 8 × 10 ⁻³ Torr. High frequency power supply 5
An alternating power of 2 to 3560 MHz is output from 3 to 13.560 MHz to generate a high-temperature non-equilibrium plasma 60 inside the discharge tube 51. 13.562 MH from the high frequency power supply 33
z, an alternating power of 1500 W is output, and a bias voltage is applied to the substrate holder-2. The substrate 1 is heated and held at 150 ° C. through the substrate holder-2. Using these conditions, Si on a large area silicon wafer with a diameter of 10 inches
An O ₂ film was deposited. The film thickness distribution was 2 μm ± 3%, and the uniformity of the film thickness was extremely good.

The following phenomenon occurs before the SiO ₂ film is deposited on the substrate. First gas introduction mechanism 70
Is introduced by the high-temperature non-equilibrium plasma 60 to generate a large amount of oxygen atoms (neutral active species). On the other hand, silane gas (SiH ₄ ) is decomposed into SiH ₃ by plasma in the processing chamber. The above-mentioned oxygen atoms are spread in the processing chamber, and react with SiH ₃ with the help of thermal energy from the heated substrate 1 to form Si atoms on the substrate 1.
An O ₂ film is deposited. The pressure in the processing chamber 3 is 2 × 10 ^{-2 to} 5
Since it is as low as × 10 ^-4 Torr, its mean free path is relatively long, and oxygen atoms often reach the inner wall surface of the processing chamber without colliding much with other particles.
An oxygen atom is a neutral active species reflection member 94 (see FIG. 2B).
Most of the light is reflected as oxygen atoms (that is, while maintaining the active state), and returns to the inside of the processing chamber.

If the neutral active species reflecting member 94 does not exist, oxygen atoms directly collide with the inner wall surface of the stainless steel processing chamber, and temporarily bond with the wall metal to form an oxide. . When an oxygen atom collides with this part further, it reacts with the oxygen atom bonded to the metal to form an oxygen molecule. Even if these oxygen molecules return to the processing chamber, they do not contribute to the film deposition reaction and are simply exhausted.

After all, according to this embodiment, a large amount of oxygen atoms generated by the high-temperature non-equilibrium plasma can contribute to the film deposition reaction without being wasted in the processing chamber.
Even at low pressures (i.e., even if the mean free path is relatively long and the neutral active species is likely to collide with the wall), high-speed film deposition can be performed.

In this embodiment, the potential control mechanism 30
Is useful for improving the step coverage of the SiO ₂ film. Oxygen atoms contribute to the reaction in the deposition of the SiO ₂ film itself as described above. However, if the potential control mechanism 30 is used, the film can be bombarded by positive ions in the processing chamber. As a result, Si on the side surface of the step portion of the pattern previously formed on the silicon wafer
The coverage of the O ₂ film can be improved. The plasma confinement effect by the multi-cusp magnetic field acts on the positive ions, and the effect of the impact operation by the positive ions is uniformly generated over a large area. Potential control mechanism 3
If 0 is not used, the step coverage characteristics will be poor. When the potential control mechanism 30 was used, the surface was flattened by depositing an SiO ₂ film to a thickness of about 2 μm on a 1 μm step existing on the wafer in advance. This technique is particularly important for a technique for fabricating a multilayer wiring and an exposure technique for a fine pattern (the depth of the subject required for exposure is small) used with an increase in the degree of integration of a semiconductor.

When both oxygen and silane are introduced from the first gas introduction mechanism 70, the reaction proceeds mainly in and near the high-temperature non-equilibrium plasma 60, and as a result, the uniformity of the substrate processing is improved. However, there is a disadvantage that the raw material gas cannot be used effectively. On the other hand, when both oxygen and silane are introduced from the second gas introduction mechanism 80, only oxygen diffused into the discharge tube 51 is activated by the high-temperature non-equilibrium plasma, and the activation efficiency of oxygen is increased. However, there is a disadvantage that the raw material gas cannot be effectively used. Therefore, it was very useful to use the first gas introduction mechanism 70 and the second gas introduction mechanism 80 together as described above for depositing the SiO2 film.

Under the above film forming conditions, when nitrous oxide gas (N ₂ O) is introduced from the first gas introducing mechanism 70 instead of oxygen gas, SiO ₂ containing a small amount of nitrogen is introduced.
A film (also referred to as a SiON film) can be manufactured. Further, when an ammonia gas or an ammonia gas diluted with nitrogen is used instead of the oxygen gas, a SiN film can be formed. This SiN film is used for passivation of semiconductor devices and for TFT (thin film transistor).
Can be used for the gate insulating film. In the case of this SiN film, the potential control mechanism 30 can control not only the step coverage but also the stress of the deposited film.

Further, when oxygen gas is introduced only from the first gas introduction mechanism 70 and the second gas introduction mechanism 80 is not used, ashing for photoresist and cleaning for removing organic substances, or cleaning. It can be used for oxidation of the surface of a substrate material. For example, in the ashing of the photoresist and the cleaning for removing the organic substances, the substrate could be effectively treated by setting the substrate temperature to about 120 ° C. In this case, the effect was greater when the flow rate of oxygen was larger than 100 sccm. Also in this case, processing with good uniformity was possible on a silicon wafer having a diameter of 10 inches.

The treatment for oxidizing the material of the substrate is effective for producing an oxide superconductor, producing a metal oxide film of tantalum, titanium, ruthenium, iridium, tungsten, aluminum, etc., and producing an oxide film of silicon. The tantalum oxide film can be used as a dielectric film for a capacitor of a semiconductor device. Titanium can be used as a titanium dioxide semiconductor electrode, and ruthenium, iridium, and tungsten oxides can be used as an ion conductive film, as a thin film for sensing materials or chromism in various sensors. Aluminum oxide can be used as an insulator thin film for various devices. The thickness of the oxide layer in these oxidation treatments is 10 mm in diameter.
The distribution was within ± 3% within the inch area, and very good uniformity could be obtained.

FIG. 3 is a front sectional view of a second embodiment of the present invention. The embodiment differs from the embodiment shown in FIG. 1 in the multi-cusp magnetic field generating mechanism, and the other parts are the same. Therefore, the same parts as those in the embodiment of FIG. 1 are denoted by the same reference numerals. The multi-cusp magnetic field generating mechanism 90a according to this embodiment includes:
A ring-shaped multi-cusp magnetic field is formed by alternately arranging magnetic poles in the vertical direction outside the side wall. Further, magnets are arranged on the upper and lower sides of the processing chamber 3. Each magnet 91a is smaller and more densely arranged than the magnet shown in FIG. In this embodiment, it takes more time to manufacture the multi-cusp magnetic field generating mechanism than in the embodiment of FIG. 1, but it is possible to increase the utilization efficiency of the active species in the processing chamber.

FIG. 4 is a front sectional view of a third embodiment of the present invention. The embodiment differs from the embodiment shown in FIG. 1 in that a discharge magnetic field generating mechanism is provided around a discharge tube 51, and the other parts are the same. Therefore, the same parts as those in the embodiment of FIG. 1 are denoted by the same reference numerals. In this embodiment, the discharge tube 5
A magnetic field generating mechanism including an electromagnet 55 is provided around the antenna 52 outside the first antenna. As a result, a magnetic field is formed vertically inside the discharge tube 51. Generating a magnetic field inside the discharge tube 51 facilitates generation and maintenance of the high-temperature non-equilibrium plasma 60 at a low pressure.

FIG. 5 is a front sectional view of a fourth embodiment of the present invention. This embodiment combines the apparatus shown in FIG. 3 with the discharge magnetic field generating mechanism shown in FIG.
This is an improvement of the shape of the antenna 52a around the discharge tube 51. FIG. 6A shows the shape of the antenna 52a. The antenna 52a is not a coil as shown in FIG. 1, but has a shape in which two rings are arranged at an interval in the vertical direction. However, these rings are continuous with one conductor. When an antenna having this shape is used, a high-temperature non-equilibrium plasma having a higher ion density can be generated. FIG. 6B shows another embodiment of a similar antenna, in which a root portion of the antenna 52b is a coaxial cable 52c.

FIG. 7 is a front sectional view of a fifth embodiment of the present invention. This embodiment is obtained by removing the first gas introduction mechanism 70 from the apparatus shown in FIG. This is disadvantageous from the viewpoint of generation of active species as described above, but has an advantage that processing and mounting of the discharge tube 51 are facilitated from the viewpoint of device manufacturing.

Next, the combination of the type of neutral active species contributing to the plasma treatment and the material of the neutral active species reflecting member will be described. Table 1 below shows the purpose of the plasma processing, the neutral active species involved in the processing, and the material of the reflecting member for effectively reflecting the neutral active species.
Some of the materials of the reflection member are indicated by abbreviations, and their meanings are shown below the table.

[0045]

[Table 1] Treatment purpose Neutral active species Reflective member SiO2 deposition O atom SG, PG, AO, TF SiN deposition N atom SG, PG, AO, SiN Etching F atom TF, AO etching Cl atom TF, SG, PG, AO Diamond film deposition H atom SiC, SiN, SG, PG, AO Diamond-like carbon film deposition H atom SiC, SiN, SG, PG, AO However, SG: quartz glass PG: Pyrex (registered trademark)
Glass AO: Al ₂ O ₃ TF: Polytetrafluoroethylene

[0046]

According to the present invention, a large amount of neutral active species is generated using high-temperature non-equilibrium plasma, and the plasma in the processing chamber is separated from the inner wall surface of the processing chamber by a multi-cusp magnetic field. It is possible to cover the inner wall surface of the processing chamber with the seed reflection member, and it is possible to prevent the neutral active species from being wasted. As a result, high-quality substrate processing can be performed at high speed and uniformly over a large area.

[Brief description of the drawings]

FIG. 1 is a front sectional view of a first embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along the line AA of FIG. 1 and an enlarged horizontal cross-sectional view near a processing chamber wall surface.

FIG. 3 is a front sectional view of a second embodiment of the present invention.

FIG. 4 is a front sectional view of a third embodiment of the present invention.

FIG. 5 is a front sectional view of a fourth embodiment of the present invention.

FIG. 6 is a perspective view showing the shape of the antenna of the embodiment shown in FIG.

FIG. 7 is a front sectional view of a fifth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Substrate 2 ... Substrate holder 3 ... Processing chamber 4 ... Active species 20 ... Temperature adjustment mechanism 30 ... Potential control mechanism 40 ... Exhaust mechanism 50 ... High-temperature non-equilibrium plasma generation mechanism 60 ... High-temperature non-equilibrium plasma 70 ... First gas Introducing mechanism 80: Second gas introducing mechanism 90: Multi-cusp magnetic field generating mechanism

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) C23C 16/00-16/56 C23F 1/00-4/04 H01L 21/205 H01L 21/3065 H05H 1 / 46 JICST file (JOIS)

Claims (2)

(57) [Claims] 1. A plasma generating chamber for generating neutral active species, a processing chamber disposed adjacent to the plasma generating chamber, and a substrate holder installed in the processing chamber and holding a substrate to be processed.
A plasma processing apparatus, comprising: an exhaust mechanism for evacuating the plasma generation chamber and the processing chamber to a vacuum; and a gas introduction mechanism for introducing gas required for surface processing of the substrate to be processed into at least one of the plasma generation chamber and the processing chamber. Oite the location, to form a multi-cusp magnetic field in the processing chamber,
On the inner wall of the processing chamber, near the cusp of the multi-cusp magnetic field
The outer wall is covered with a reflection member of neutral active species, and this neutral active species
The material of the reflection member is different from that of the processing chamber components.
And a plasma processing apparatus. 2. The material of said neutral active species reflecting member is oxidized.
Substance, fluororesin or silicon compound
The plasma processing apparatus according to claim 1, wherein: