JPH08330241A - Method of preventing clog of gas vent in film former, and film former where this clogging prevention method is executed - Google Patents

Abstract

PURPOSE: To prevent the drop of film growth speed and the inequalization of film thickness by providing a constitution which can effective prevent the clogging of the gas vent in a film former. CONSTITUTION: It is introduced, being mixed in monosilane gas or the like having film depositing action, into the gas vent 35 of the gas introducer 322 constituting a gas introduction mechanism 3. In the plasma being produced in a gas plasma production chamber 1 by the energy given by a power supply mechanism, fluorine active species or fluorine ions are produced, and by those being supplied to gas vents 35, the film deposited on the gas vents 35 is suppressed, and the clogging is prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin film forming apparatus used in the production of various semiconductor devices, liquid crystal displays and the like, and in particular, a gas is blown out from a gas outlet to produce a gas in a plasma generating chamber. The present invention relates to a thin film forming apparatus of the type that introduces.

[0002]

2. Description of the Related Art In manufacturing various semiconductor devices, liquid crystal displays and the like, a predetermined thin film is formed on a substrate. FIG. 6 is a schematic diagram illustrating the configuration of an example of a conventional thin film forming apparatus of this type, which is plasma CVD.
An apparatus for forming a thin film by (chemical vapor deposition) is illustrated.

Further, the thin film forming apparatus of FIG. 6 generates plasma by a plasma generation chamber 1, a power supply mechanism 2 for supplying electric power to the plasma generation chamber 1, and electric power supplied by the power supply mechanism 2. A gas introduction mechanism 3 for introducing gas into the plasma generation chamber 1 is provided. The thin film forming apparatus of FIG. 6 has a film formation chamber 4 and a vacuum exhaust chamber 5 in addition to the plasma generation chamber 1. As shown in FIG. 6, the plasma generation chamber 1 is a small space located above the film formation chamber 4, and the vacuum exhaust chamber 5 is a slightly larger space located below the film formation chamber 4.

The film forming chamber 4 and the vacuum exhaust chamber 5 are constituted by one or two vacuum containers 6 which are hermetically connected. An exhaust system 7 for exhausting the inside is connected to the vacuum container 6, and the exhaust system 7 includes a roughing pump 71 and a roughing pump 7
The main pump 72 is arranged in the preceding stage of No. 1, and the main valve 73 and the variable conductance valve 74 which are arranged on the exhaust path exhausted by these pumps 71, 72 are mainly configured. A dry pump is used as the roughing pump 71, and a turbo molecular pump is used as the main pump 72. Plasma generation chamber 1
Is a bell jar 11 hermetically connected to the vacuum container 6.
It is composed by. The bell jar 11 has a cylindrical shape with a diameter of about 100 mm having a hemispherical end and an opening at the lower end, and is made of a dielectric material such as quartz glass. The vacuum container 6 has a circular opening at the center of the upper wall, and the bell jar 11 is arranged by airtightly connecting to this opening.

The power supply mechanism 2 is mainly composed of a high frequency coil 21 arranged around the bell jar 11 and a high frequency power source 23 for supplying high frequency power to the high frequency coil 21 via a matching unit 22. There is. As the high frequency power supply 23, for example, one that generates high frequency power of 400 kHz is adopted, and the high frequency power is supplied from the high frequency coil 21 into the bell jar 11.

In the example shown in FIG. 6, the gas introduction mechanism 3 is composed of two gas introduction systems 31 and 32 so that two different gases can be introduced simultaneously. Each of the gas introduction systems 31 and 32 is mainly composed of pipes 311 and 321 connected to a gas cylinder (not shown), and gas introduction bodies 312 and 322 connected to the ends of the pipes 311 and 321.

FIG. 7 is a diagram for explaining the structure of the gas introduction body. As shown in FIG. 7, gas introduction bodies 312, 32
2 is composed of an annular pipe having a circular cross section.
The gas introduction bodies 312 and 322 are supported by a support rod 33 provided in the vacuum container 6, and are horizontally arranged along the inner surface of the vacuum container 6. The vacuum container 6 may have a cylindrical shape or a rectangular tube shape. Further, a transport pipe 34 is provided in a state of penetrating the wall of the vacuum container 6 in an airtight manner.
It is connected to 322. The other ends of the gas introduction bodies 312 and 322 are connected to the pipes 311 and 321 of FIG. And, as shown in FIG. 7, each of the gas introduction bodies 312 and 322 has a gas outlet 35 on its inner surface. The gas outlet 35 is an opening having a diameter of about 0.5 mm, and is provided on the circumference at intervals of about 4 mm.

On the other hand, returning to FIG. 6, a substrate holder 8 is provided in the vacuum container 6 below the bell jar 11. The substrate holder 8 mounts a substrate 9 on which a thin film is to be formed on its upper surface, and incorporates a temperature adjusting mechanism 81 for heating or cooling the substrate 9 as necessary. Also,
A substrate bias power supply 82 for applying a predetermined bias voltage to the substrate 9 by the interaction between the generated plasma and the high frequency is connected to the substrate holder 8 and applies a predetermined high frequency.

The thin film forming apparatus shown in FIGS. 6 and 7 operates as follows. First, the substrate 9 is loaded into the vacuum container 6 through a gate valve (not shown) provided in the vacuum container 6, and placed on the substrate holder 8. The gate valve is closed and the exhaust system 7 is operated to move the inside of the vacuum container 6 to, for example, 5 mTo
Exhaust to about rr. Next, the gas introducing mechanism 3 is operated to introduce a predetermined gas into the vacuum container 6 at a predetermined flow rate. At this time, the gas flows from the pipes 311 and 321 to the transportation pipe 3
It is supplied to the gas introduction bodies 312 and 322 via 4 and is introduced into the vacuum container 6 so as to be blown inward from the gas blowing ports 35 of the gas introduction bodies 312 and 322. The introduced gas diffuses in the vacuum container 6 and reaches the bell jar 11.

In this state, the power supply mechanism 2 is operated, and the high frequency power supply 23 and the high frequency coil 21 through the matching unit 22.
Apply high frequency power to the. This high-frequency power is supplied into the bell jar 11 by the high-frequency coil 21 to give energy to the gas present in the bell jar 11 to generate plasma. The generated plasma is bell jar 1
Diffuse from 1 toward the lower substrate 9. A predetermined gas phase reaction occurs in the plasma, and a predetermined thin film is deposited on the substrate 9 by the decomposition products and the like generated by this gas phase reaction. For example, when forming a silicon oxide thin film, monosilane gas is introduced by the first gas introduction system 31 and oxygen gas is introduced by the second gas introduction system 32. The monosilane / oxygen plasma decomposes monosilane and reacts with oxygen to form a silicon oxide thin film.

[0011]

In the above conventional thin film forming apparatus, when a thin film is formed, there is a problem that a thin film is deposited on the gas outlet of the gas introducing member and the gas outlet is clogged. It was Further, even if the gas is not completely clogged, a thin film is deposited on the gas outlet, and as a result, the amount of gas blown out is reduced. As a result, the film formation rate on the substrate is reduced, and a problem arises that the film thickness does not reach a predetermined value even if film formation is performed for a predetermined time, or the film formation time is longer than expected. Furthermore, the thin film deposition on the gas outlets does not occur uniformly at each gas outlet. Therefore, the decrease in the gas blowing amount occurs unevenly at each gas blowing port, and as a result,
The gas distribution in the vacuum container becomes uneven. When this occurs, the film thickness distribution of the thin film deposited on the substrate becomes non-uniform.

The present invention has been made to solve the above problems, and provides an effective structure capable of preventing clogging of a gas blowing port in a thin film forming apparatus, thereby lowering the film forming rate and reducing the film thickness. The purpose is to prevent nonuniformity in advance.

[0013]

In order to achieve the above-mentioned object, the invention according to claim 1 of the present invention comprises:
An electric power supply mechanism for applying electric power to the plasma generation chamber, and a gas introduction mechanism for introducing a gas that generates plasma into the plasma generation chamber by the electric power supplied by the power supply mechanism, and the generated plasma causes an object A thin film forming apparatus for forming a predetermined thin film on the surface of the plasma generating chamber, wherein the gas introducing mechanism has a gas introducing body for blowing gas from a gas outlet in the plasma generating chamber. Is introduced into the gas, and the generated plasma produces fluorine-based active species or fluorine-based ions from the fluorine-based gas, and the fluorine-based active species or fluorine-based ions are supplied to the gas outlet, whereby the gas outlet The method is a method of suppressing the deposition of a thin film on the surface to prevent clogging. Similarly, in order to achieve the above-mentioned object, the invention according to claim 2 is the above-mentioned claim 1.
In the above configuration, the introduction amount of the fluorine-based gas is selected in the range of 1% to 50% with respect to the total introduction amount of the gas. Similarly, in order to achieve the above object, the invention according to claim 3 is the structure according to claim 1 or 2, wherein hydrogen gas is introduced into the plasma generation chamber together with the fluorine-based gas. Similarly, in order to achieve the above object, the invention of claim 4 is the same as claim 1, 2 or 3.
A thin film forming apparatus in which the described method for preventing clogging is implemented, wherein a plasma generation chamber, a power supply mechanism for applying power to the plasma generation chamber, and plasma generated by the power supplied by the power supply mechanism. A thin film forming apparatus for forming a predetermined thin film on the surface of an object by the generated plasma, the gas introducing mechanism having a gas introducing mechanism for introducing gas into the plasma generating chamber, An introduction body is provided in the plasma generation chamber, and the gas introduction mechanism uses a fluorine-based gas so that the plasma generates a fluorine-based active species or fluorine-based ions that can be supplied to the gas outlet. It has a configuration that can be introduced into. Similarly, in order to achieve the above object, in the invention of claim 5, in the structure of claim 4, the gas introduction system mixes the fluorine-based gas with a gas that causes a thin film deposition action by the generated plasma. And is introduced into the plasma generation chamber from the gas outlet. Similarly, in order to achieve the above object, the invention according to claim 6 is the structure according to claim 4 or 5, wherein the gas introducing member is an inner surface of a vacuum container in which a film is formed by the plasma generated by the plasma generating chamber. Is a pipe-shaped member arranged along the line, and prevents the plasma from reaching the inner surface of the vacuum container to prevent plasma loss on the inner surface, and the plasma to the gas outlet of the gas introduction body. Of the plasma control magnet for accelerating the arrival of Similarly, in order to achieve the above-mentioned object, the invention according to claim 7 is the structure according to claim 4 or 5, further comprising a vacuum chamber in which a film forming chamber in which a thin film is formed is formed separately from the plasma generating chamber. The gas introduction body is arranged at a predetermined position in the vacuum container, and has a configuration in which a magnet is provided to set a magnetic force line for transporting the plasma generated in the plasma generation chamber to the gas introduction body.

[0014]

EXAMPLES Examples of the present invention will be described below. FIG.
FIG. 3 is a schematic diagram illustrating a configuration of a thin film forming apparatus in which the clogging prevention method of the present invention is implemented. At the same time, it is also a schematic view of an embodiment of the thin film forming apparatus. The thin film forming apparatus shown in FIG. 1 is similar to the apparatus shown in FIG. 6, and has a plasma generation chamber 1, a power supply mechanism 2 for applying power to the plasma generation chamber 1, and a plasma generated by the power supplied by the power supply mechanism 2. And a gas introduction mechanism 3 for introducing the gas for generating the gas into the plasma generation chamber 1. And the plasma generation chamber 1
Is disposed above the film forming chamber 4, and the vacuum exhaust chamber 5 is disposed below the film forming chamber 4.

The apparatus shown in FIG. 1 is different from the apparatus shown in FIG. 6 in the structure of the gas introduction mechanism 3. That is, the gas introduction mechanism 3 shown in FIG. 1 has a third gas introduction system 33 in addition to the first and second gas introduction systems 31 and 32. The third gas introduction system 33 is configured to introduce a fluorine-based gas. Further, in the apparatus of this embodiment, like the apparatus of FIG. 6, the first gas introduction system 31 is configured to introduce the monosilane gas, and the second gas introduction system 32 is configured to introduce the oxygen gas. .

Each of the gas introduction systems 31, 32 and 33 is provided with a pipe 3 for supplying gas from a gas cylinder storing a predetermined gas.
Flow rate regulator 313 arranged on 11, 321, 331
323 and 333 are provided. The pipe 331 of the third gas introduction system 33 that supplies fluorine gas is connected to the pipe 311 of the first gas introduction system 31 that supplies monosilane gas. That is, the apparatus of this embodiment is configured so that the monosilane gas and the fluorine-based gas are mixed and introduced.

In the apparatus of this embodiment, the plasma control magnet 61 is arranged on the outer surface of the vacuum container 6. Figure 2
[Fig. 2] is a schematic plan sectional view for explaining the configuration of a plasma control magnet 61 adopted in the apparatus of Fig. 1. As shown in FIGS. 1 and 2, the plasma control magnet 61 is a plurality of plate-shaped permanent magnets arranged so as to contact the outer surface of the vacuum container 6 and extend vertically. Each plasma control magnet 61 is
The magnetic poles on the inner surface of the vacuum container 6 are configured to be different from each other, and a cusp magnetic field as shown in FIG. 2 is formed along the inner surface of the vacuum container 6.

By disposing the plasma control magnet 61 in this way, plasma loss on the inner surface of the vacuum container 6 is prevented, and the processing efficiency for depositing a thin film on an object is improved. Further, in particular, in the apparatus of the present embodiment, the pipe-shaped gas introduction bodies 312, 322, 3 similar to those shown in FIG.
32 is arranged along the inner surface of the vacuum container 6. Figure 2
The magnetic field lines of the cusp magnetic field set as above capture the plasma in the vicinity of the gas introduction bodies 312 and 322 and prevent the plasma from diffusing, so that the arrival of the plasma at the gas outlet 35 is promoted and generated in the plasma. The resulting fluorine-based active species and fluorine-based ions are effectively supplied to the gas outlet 35. The configuration of the device other than the above is almost the same as the device of FIG.

Next, an embodiment of the invention of the clogging prevention method will be described while explaining the operation of the thin film forming apparatus of this embodiment. In the thin film forming apparatus of this embodiment, the first gas introduction system 31 and the third gas introduction system 33 mix the monosilane gas and the fluorine-based gas while mixing the first gas introduction body 31.
2, and oxygen gas is supplied to the second gas introduction body 322 by the second gas introduction system 32. Then, when the power supply mechanism 2 is operated, plasma by these gases is generated in the bell jar 11, and a silicon oxide thin film is deposited on the substrate 9 by a predetermined vapor phase growth reaction.

At this time, the fluorine-based gas blown out from the first gas introduction body 312 produces fluorine-based active species or fluorine-based ions in the plasma. The fluorine-based active species or fluorine-based ions operate to etch the thin film deposited on the gas outlet 35, and suppress the thin film deposition on the gas outlet 35. For example, when silicon tetrafluoride gas is introduced as a fluorine-based gas, plasma produces active species such as SiF ^* and F ^* , and ions such as SiF ⁺ and F ⁺ . These active species and ions etch the deposited silicon oxide thin film and prevent the thin film from growing.

It is important to select the introduction amount of the fluorine-based gas. According to a study by the inventor, if the amount of gas introduced into the vacuum container 6 is less than 1%, the effect of preventing clogging cannot be sufficiently obtained. On the other hand, when the amount of the fluorine-based gas introduced increases, a large amount of fluorine-based active species and ions are generated by the plasma, so that the gas introduction bodies 312, 322.
There is a problem that the surface of the is chemically corroded by being etched. When the gas introduction bodies 312 and 322 are made of stainless steel, such a problem does not occur, but when they are made of an aluminum alloy or the like, the introduction amount of the fluorine-based gas is 50% of the total gas introduction amount. Above the above range, the above corrosion problem occurs. Therefore, it is preferable to set the introduction amount to 1% or more and 50% or less. In addition, specifically, each gas introduction system 3
Flow rate adjusters 313, 32 provided at 1, 32, 33
3,333 is controlled so that the flow rate ratio of the fluorine-based gas is this ratio to the flow rate of all gases.

FIG. 3 and FIG. 4 are diagrams showing experimental results for confirming the effect of the clogging prevention method of the above-mentioned embodiment. First, FIG. 3 shows the thin film forming apparatus of FIG. 1 or FIG.
FIG. 4 is a graph showing a result of a deposition process of a silicon oxide thin film having a thickness of 0.4 μm on a 6-inch silicon semiconductor wafer, showing a change in in-plane film formation average speed with respect to the number of processed semiconductor wafers. . The vertical axis in FIG. 3 represents the average in-plane film formation rate of the silicon oxide thin film, and the horizontal axis represents the number of processed semiconductor wafers. Average in-plane deposition rate is 6 inches of silicon semiconductor wafer diameter 1
The film forming rate was measured at 56 points in the area inside 40 mm, and the average value was obtained.

The polygonal line A (● marker) is the change in the in-plane average film formation rate of the silicon oxide thin film when the conventional apparatus of FIG. 6 is used, and the polygonal line B (■ marker) is shown in FIG. 5 is a change in in-plane average film formation rate of a silicon oxide thin film containing fluorine when the thin film forming apparatus of the example is used. In the polygonal line A, the average value of the film forming rate tends to decrease after the film forming process of the semiconductor wafer is started, and the degree of decrease is remarkable especially after the number exceeds 70. Then, when the number of sheets exceeds 100, the average film formation speed of 400 nm / min at the start of film formation is reduced to a half of 200 nm / min or less. The flow rate of each gas when the data of this broken line A was obtained was 90 sccm for monosilane and 180 sccm for oxygen. Note that sccm is s
standard cubic centimeter
It is an abbreviation for "permute" and is represented by the amount (volume) of gas flowing at 1 ° C. and 0 ° C. per minute. On the other hand, in polygonal line B, the number of semiconductor wafers subjected to film formation is 200.
Up to the number of sheets, the average film forming speed is about 330 nm / min, which is a substantially constant value. The flow rate of each gas when the data of this broken line B was obtained was 90 sccm of monosilane, 180 sccm of oxygen, and 10 sccm of silicon tetrafluoride.

Further, FIG. 4 shows that the thin film forming apparatus of FIG. 1 or 6 is used to form 0.4 μm on a 6-inch silicon semiconductor wafer.
It is a figure of a result of performing a deposition process of a silicon oxide thin film with a thickness of m, and is a graph showing a change in non-uniformity of the in-plane film thickness distribution of the silicon oxide thin film with respect to the number of processed semiconductor wafers. is there. The vertical axis in FIG. 4 represents the non-uniformity of the in-plane film thickness distribution of the silicon oxide thin film, and the horizontal axis represents the number of processed semiconductor wafers. The non-uniformity of the in-plane film thickness distribution was obtained by measuring the film thickness at 56 points in a region inside a diameter of 140 mm of a 6-inch silicon semiconductor wafer.

In FIG. 4, a polygonal line C (marker ○) is a change in the non-uniformity of the in-plane film thickness distribution of the silicon oxide thin film when the conventional apparatus of FIG. 6 is used, and a polygonal line D (marker ○). 3 is a change in non-uniformity of the in-plane film thickness distribution of the silicon oxide thin film containing fluorine when the thin film forming apparatus of the embodiment shown in FIG. 1 is used. In the polygonal line C, the non-uniformity of the in-plane film thickness distribution tends to increase after the semiconductor wafer film formation process is started.
In particular, the degree of rise is remarkable from around 70 sheets,
The non-uniformity exceeds 10%. The flow rate of each gas when the data of this broken line C was obtained was 90 sccm for monosilane and 180 sccm for oxygen. On the other hand, polygonal line D
Shows that the non-uniformity of the in-plane film thickness distribution maintains a good value of 6% or less when the number of film forming treatments of semiconductor wafers is 200. The flow rate of each gas when the data of this broken line D was obtained was 90 sccm of monosilane, 200 sccm of oxygen, and 10 sccm of silicon tetrafluoride.

Further, after the film formation process of 200 semiconductor wafers, the first gas introduction body shown in FIG. 1 or 6 is taken out from the film formation chamber 4 and the deposition state of the thin film in the gas outlet 35 is observed. In the one used in the conventional thin film forming apparatus of FIG. 6, deposition of a laminated film was observed inside the gas outlet 35. Further, in some places, a gas outlet 35 that was completely blocked was also observed. However,
In the case of using the thin film forming apparatus of the embodiment shown in FIG. 1, deposition of a laminated film on the gas outlet 35 was not observed.

As described above, by supplying the fluorine-based gas such as silicon tetrafluoride, it is possible to prevent the gas blowout port 35 from being clogged, and the average in-plane film formation rate decreases with respect to the number of thin film deposition processes. It also has an effect of suppressing deterioration of the in-plane film thickness distribution. Further, in particular, in the above embodiment, since the fluorine-based gas and the gas having the thin film deposition action are mixed and supplied, the clogging effect of the gas outlet 35 is further improved as compared with the case where they are supplied separately. The amount of fluorine-based gas introduced is 1% or more with respect to the total amount of gas introduced as described above. 5
It is preferably 0% or less, but more preferably selected in the range of 5% or more and 20% or less. That is, if it is 5% or more, the effect of suppressing the film deposition on the structures in the film forming chamber 4 is suppressed, and if it is 20% or less, the content of excessive fluorine in the thin film formed on the substrate 9 is increased. Can be suppressed.

As the fluorine-based gas, in addition to the above-mentioned silicon tetrafluoride gas, dihydrogen hexafluoride gas and CFC 14 gas (CF) are used.
Gases such as ₄ ) and Freon 116 gas (C ₂ F ₆ ) can be used. Further, as a gas for depositing a thin film, in the case of forming a silicon oxide thin film, disilane gas, tetraethyl orthosilicate gas (Si (C
₂ H ₅ O) ₄ ), octamethylcyclotetrasiloxane gas (Si ₄ C ₈ H ₂₄ O ₄ ) and the like can be used. Also,
When forming a silicon nitride thin film, nitrogen gas may be used instead of the oxygen gas. Furthermore, monosilane,
A combination of argon, oxygen and hydrogen gases can also be used. Further, in particular, when hydrogen gas is used together with fluorine-based gas, hydrogen reacts with fluorine on the surface of the object to form hydrogen fluoride having a high vapor pressure, so that the effect of suppressing incorporation of fluorine into the thin film is suppressed. is there. In plasma, fluorine-based active species or fluorine-based ions chemically react with free hydrogen or hydrogen ions to form active hydrogen fluoride. Since the active hydrogen fluoride has a strong etching action on a thin film of silicon oxide or the like, the effect of preventing the thin film deposition of the gas outlet 35 is further improved.

Next, another embodiment of the thin film forming apparatus of the present invention will be described. FIG. 5 is a schematic diagram illustrating the configuration of another embodiment of the thin film forming apparatus. The thin film forming apparatus of this embodiment generates helicon wave plasma to form a thin film. In this device, a loop antenna 24, which is formed by bending one rod-shaped member into a round loop shape having two upper and lower stages, replaces the high frequency coil 21 of FIG.
1 are arranged so as to surround the antenna 1, and the high frequency power supplies 23 to 13.
A high frequency of 56 MHz is supplied.

Two electromagnets 25 are concentrically arranged so as to surround the outside of the antenna 24. The two electromagnets 25 are adjusted in the winding direction and the energizing direction of the coils so that magnetic fields in opposite directions are formed.
When the two electromagnets 25 are concentrically arranged and the winding direction and the energization direction of the coil are adjusted in this way, there is an advantage that a magnetic field having a desired shape and strength can be easily created. The two electromagnets 25 are energized by direct current, and the magnetic field strength near the central axis of the bell jar 11 is set to about 100 gauss, for example.

The apparatus of FIG. 5 produces a helicon wave plasma in the bell jar 11 with such a configuration. The helicon wave plasma utilizes the fact that an electromagnetic wave with a frequency lower than the plasma frequency propagates in the plasma without being attenuated when a strong magnetic field is applied, and has recently attracted attention as a technology that can generate high-density plasma at low pressure. There is something. When the propagation direction of the electromagnetic wave in the plasma and the direction of the magnetic field are parallel, the electromagnetic wave becomes circularly polarized light in a certain fixed direction and travels spirally. For this reason, it is called helicon wave plasma.

Also in the apparatus of FIG. 5, as described above,
A fluorine-based gas is mixed with the thin film forming gas and introduced. As a result, thin film deposition on the gas outlet 35 is suppressed, and clogging is prevented in advance. Also, the electromagnet 25
Sets a magnetic field line that spreads from the lower end opening of the bell jar 11 into the film forming chamber 4, so that the plasma is efficiently transported to the film forming chamber 4 by this magnetic field line. The lines of magnetic force also promote the transport of plasma to the gas outlets 35 of the gas introduction bodies 312 and 322. Therefore, plasma is more efficiently supplied to the gas outlet 35, and the above-described thin film deposition suppressing effect is further improved.

In each of the above-described embodiments, as the object for forming a thin film, in addition to the semiconductor wafer, a transparent substrate for liquid crystal displays, substrates for various information recording media, magnetic heads, various sensors, etc. are manufactured. It is possible to target a head or the like at the time. In addition, although the case where the annular pipe member is used as the gas introduction body has been described in each of the above-described embodiments, the present invention is not limited to the annular pipe member, and for example, the wall of the vacuum container 6 can be formed. It is also possible to form a tunnel-shaped gas introduction hole through which the gas is passed and blow the gas out from the opening (gas blowing port) at the tip.

[0034]

As described above, according to the invention of claim 1 or 4 of the present application, it is possible to effectively prevent the clogging of the gas blowing port, so that the film forming speed is reduced and the film thickness is made uneven. Can be prevented. Further, according to the invention of claim 2, in addition to the effect of claim 1, it is possible to effectively prevent the deposition of a thin film on the gas outlet without corroding the gas introducing body. Further, according to the invention of claim 3, hydrogen reacts with fluorine on the surface of the object to form hydrogen fluoride having a high vapor pressure, so that there is an effect that the incorporation of fluorine into the thin film is suppressed. Further, since active hydrogen fluoride having a strong etching action generated in plasma is formed, the effect of preventing thin film deposition at the gas outlet is further improved. Further, according to the invention of claim 5, in addition to the effect of claim 4, since the fluorine-based gas is mixed with the gas having the thin film deposition action and introduced, the gas is blown out as compared with the case where they are introduced separately. The effect of preventing thin film deposition on the mouth is further improved. Further, according to the invention of claim 6, in addition to the effect of claim 4 or 5, the loss of plasma on the inner surface of the vacuum container is prevented, and the efficiency of the thin film deposition process on the object is improved. Since the arrival of plasma at the gas outlet is promoted, the effect of preventing thin film deposition at the gas outlet is further improved. Further, according to the invention of claim 7, the plasma generated in the plasma generation chamber is transported to the gas introduction body by the magnetic force lines, so that the effect of preventing thin film deposition on the gas outlet is further improved.

[Brief description of drawings]

FIG. 1 is a schematic diagram illustrating the configuration of a thin film forming apparatus in which a method for preventing clogging of the present invention is implemented.

FIG. 2 is a schematic plan cross-sectional view illustrating the configuration of a plasma control magnet used in the apparatus of FIG.

FIG. 3 is a diagram showing experimental results for confirming the effect of the clogging prevention method of the example.

FIG. 4 is a diagram showing experimental results for confirming the effect of the clogging prevention method of the example.

FIG. 5 is a schematic diagram illustrating the configuration of another embodiment of the thin film forming apparatus.

FIG. 6 is a schematic diagram illustrating a configuration of an example of a conventional thin film forming apparatus.

FIG. 7 is a diagram illustrating a configuration of a gas introduction body.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Plasma generation chamber 2 Electric power supply mechanism 25 Electromagnet 3 Gas introduction mechanism 312 Gas introduction body 322 Gas introduction body 35 Gas blowout port 4 Film formation chamber 5 Vacuum exhaust chamber 6 Vacuum container 61 Plasma control magnet 7 Exhaust system 8 Substrate holder 9 Target Substrate as a thing

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[Procedure amendment]

[Submission date] September 20, 1995

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be amended] Claims

[Correction method] Change

[Correction content]

[Claims]

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0013

[Correction method] Change

[Correction content]

[0013]

In order to achieve the above-mentioned object, the invention according to claim 1 of the present invention comprises:
A power supply mechanism for supplying power to the plasma generating chamber, and a gas introduction mechanism power supply mechanism for introducing a gas for generating a plasma by the electric power supplied to the plasma generating chamber, generated object by plasma A thin film forming apparatus for forming a predetermined thin film on the surface of the plasma generating chamber, wherein the gas introducing mechanism has a gas introducing body for blowing gas from a gas outlet in the plasma generating chamber. Is introduced into the gas, and the generated plasma produces fluorine-based active species or fluorine-based ions from the fluorine-based gas, and the fluorine-based active species or fluorine-based ions are supplied to the gas outlet, whereby the gas outlet The method is a method of suppressing the deposition of a thin film on the surface to prevent clogging. Similarly, in order to achieve the above-mentioned object, the invention according to claim 2 is the above-mentioned claim 1.
In the above configuration, the introduction amount of the fluorine-based gas is selected in the range of 1% to 50% with respect to the total introduction amount of the gas. Similarly, in order to achieve the above object, the invention according to claim 3 is the structure according to claim 1 or 2, wherein hydrogen gas is introduced into the plasma generation chamber together with the fluorine-based gas. Similarly, in order to achieve the above object, the invention of claim 4 is the same as claim 1, 2 or 3.
A thin film forming apparatus for carrying out a method for preventing clogging as described above, wherein power is supplied to the plasma generation chamber and the plasma generation chamber.
A power supply mechanism for supplying, and a gas introduction mechanism power supply mechanism for introducing a gas for generating a plasma by the electric power supplied to the plasma generating chamber, a predetermined thin film on the surface of the resulting object by plasma In the thin film forming apparatus for forming, the gas introduction mechanism has a gas introduction body for blowing gas from a gas blowout port in the plasma generation chamber, and the gas introduction mechanism is a fluorine that can be supplied to the gas blowout port. It has a configuration in which a fluorine-based gas can be introduced into the plasma generation chamber so that the system active species or fluorine-based ions are generated by the plasma. Similarly, in order to achieve the above object, the invention according to claim 5 is the structure of claim 4 in which the gas introduction mechanism is
It is configured such that a gas that causes a thin film deposition action by the generated plasma is mixed with the fluorine-based gas and introduced into the plasma generation chamber from the gas outlet. Similarly, in order to achieve the above object, the invention according to claim 6 is the structure according to claim 4 or 5, wherein the gas introducing member is an inner surface of a vacuum container in which a film is formed by the plasma generated by the plasma generating chamber. Is in the shape of a pipe arranged along the line, and prevents the plasma from reaching the inner surface of the vacuum container to prevent the loss of plasma on the inner surface, and the plasma to the gas outlet of the gas introducing body. Of the plasma control magnet for accelerating the arrival of Similarly, in order to achieve the above-mentioned object, the invention according to claim 7 is the structure according to claim 4 or 5, further comprising a vacuum chamber in which a film forming chamber in which a thin film is formed is formed separately from the plasma generating chamber. The gas introduction body is arranged at a predetermined position in the vacuum container, and has a configuration in which a magnet is provided to set a magnetic force line for transporting the plasma generated in the plasma generation chamber to the gas introduction body.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0034

[Correction method] Change

[Correction content]

[0034]

As described above, according to the invention of claim 1 or 4 of the present application, it is possible to effectively prevent the clogging of the gas blowing port, so that the film forming speed is reduced and the film thickness is made uneven. Can be prevented. Further, according to the invention of claim 2, in addition to the effect of claim 1, it is possible to effectively prevent the deposition of a thin film on the gas outlet without corroding the gas introducing body. Further, according to the invention of claim 3, hydrogen reacts with fluorine on the surface of the object to form hydrogen fluoride having a high vapor pressure, so that there is an effect that the incorporation of fluorine into the thin film is suppressed. Further, since active hydrogen fluoride having a strong etching action generated in plasma is formed, the effect of preventing thin film deposition at the gas outlet is further improved. Further, according to the invention of claim 5, in addition to the effect of claim 4, since the fluorine-based gas is mixed with the gas having the thin film deposition action and introduced, the gas is blown out as compared with the case where they are introduced separately. The effect of preventing thin film deposition on the mouth is further improved. Further, according to the invention of claim 6, in addition to the effect of claim 4 or 5, the loss of plasma on the inner surface of the vacuum container is prevented, and the efficiency of the thin film deposition process on the object is improved. Since the arrival of plasma at the gas outlet is promoted, the effect of preventing thin film deposition at the gas outlet is further improved. Further, according to the invention of claim 7, the plasma generated in the plasma generation chamber is transported to the gas introduction body by the magnetic force lines, so that the effect of preventing thin film deposition on the gas outlet is further improved.

Claims (7)

[Claims] 1. A plasma generation chamber, a power supply mechanism for applying power to the plasma generation chamber, and a gas introduction mechanism for introducing a gas that generates plasma into the plasma generation chamber by the power supplied by the power supply mechanism. A thin film forming apparatus for forming a predetermined thin film on the surface of an object by the generated plasma, wherein the gas introduction mechanism has a gas introduction body for blowing out gas from a gas outlet in a plasma generation chamber. In the apparatus, a fluorine-based gas is introduced into the plasma generation chamber, the generated plasma generates fluorine-based active species or fluorine-based ions from the fluorine-based gas, and the fluorine-based active species or fluorine-based ions are discharged from the gas outlet. To suppress clogging by suppressing the deposition of thin film on the gas outlet. Clogging prevention method of definitive gas blow-out port. 2. The gas blowing in the thin film forming apparatus according to claim 1, wherein the introduction amount of the fluorine-based gas is selected in the range of 1% to 50% with respect to the total introduction amount of the gas. A method to prevent clogging of the mouth. 3. The method for preventing clogging of a gas outlet in a thin film forming apparatus according to claim 1, wherein hydrogen gas is introduced into the plasma generation chamber together with the fluorine-based gas. 4. A thin film forming apparatus for carrying out the method for preventing clogging according to claim 1, 2, or 3, wherein a plasma generation chamber, a power supply mechanism for applying power to the plasma generation chamber, and a power supply. A thin film forming apparatus for forming a predetermined thin film on a surface of an object by the generated plasma, the gas introducing mechanism introducing a gas that generates plasma into the plasma generation chamber by the electric power supplied by the supply mechanism, The mechanism has a gas introduction body that blows out gas from a gas outlet in the plasma generation chamber, and the gas introduction mechanism supplies a fluorine-based active species or fluorine-based ions that can be supplied to the gas outlet, to the plasma. The thin film forming apparatus is characterized in that a fluorine-based gas can be introduced into the plasma generation chamber so as to generate. 5. The gas introduction system is characterized in that a gas that causes a thin film deposition action by the generated plasma is mixed with the fluorine-based gas and introduced into the plasma generation chamber from the gas outlet. The thin film forming apparatus according to claim 4. 6. The gas introduction body is a pipe-shaped member arranged along an inner surface of a vacuum container where a film is formed by the generated plasma, and suppresses the arrival of the plasma on the inner surface of the vacuum container. 6. A plasma control magnet is arranged to prevent the plasma loss on the inner surface and to promote the arrival of the plasma at the gas outlet of the gas introducing body. Thin film forming equipment. 7. A vacuum container is provided, in which a film forming chamber for forming a thin film is formed separately from the plasma generating chamber, and the gas introducing body is arranged at a predetermined position in the vacuum container. 5. A magnet is provided for setting a magnetic field line for transporting the generated plasma to the gas introduction body.
Alternatively, the thin film forming apparatus described in item 5.