JP2002151507A - Semiconductor element manufacturing method and apparatus thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor element manufacturing method along with an apparatus thereof which generates a uniform plasma under a pressure near the atmospheric pressure successively for manufacturing an oxide film in a semiconductor element manufacturing process, treats a base with the plasma and forms a good oxide film on the base. SOLUTION: The semiconductor element manufacturing method along with the apparatus thereof comprises a step for setting a solid dielectric on at least one opposite surface of a pair of opposed electrodes under a pressure near the atmospheric pressure, introducing a process gas between the pair of electrodes, applying a pulse-like electric field to obtain a plasma, contacting the plasma to a base, and holding an atmosphere containing one or more components selected from nitrogen, argon, helium, neon, xenon and dry air near the contact parts of the base with the plasma in forming an oxide film for semiconductor elements by the plasma CVD.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for forming an oxide film used for an interlayer insulating film, a passivation film and the like in a semiconductor device on a substrate surface by a plasma CVD method.

[0002]

2. Description of the Related Art Generally, a general structure of a semiconductor device is that a gate electrode, a gate insulating film, a silicon film, a source insulator, a drain insulating film, a source electrode, a drain electrode, a passivation film (protective film) are formed on a substrate. And so on. Here, the substrate is made of a glass substrate or a wafer substrate, the electrodes are made of a metal or a metal compound such as Al or Cu, and the interlayer insulator including the passivation film is silicon oxide, silicon nitride, or the like. It is made of silicon carbide or the like, and the silicon layer is made of a material such as a Si single crystal layer, an a-Si layer, and a-Si doped with P, B, As, Ge, or the like.

[0003] In a semiconductor device, these materials are combined according to required functions, and after cleaning a substrate or the like, a thin film such as an electrode, an insulating film, or a silicon layer is formed thereon. (For example, coating, developing, baking, resist stripping, etc.), and subsequently, a complicated process of repeating exposure, development, etching and the like. In these manufacturing steps, it is important to form a thin film such as an insulating film, a protective film, an electrode, and a silicon layer, and a plasma processing method is mainly used as the forming method.

As a method of forming a thin film, there are generally low pressure plasma CVD, normal pressure thermal CVD, vapor deposition, sputtering and the like. In the conventional atmospheric pressure plasma CVD, the gas species is limited, such as in a helium atmosphere. For example,
A method of performing treatment in a helium atmosphere is disclosed in JP-A-2-486.
Japanese Patent Application Laid-Open No. 4-745 discloses a method for performing a treatment in an atmosphere comprising argon, acetone and / or helium.
No. 25 discloses this.

However, in each of the above methods, plasma is generated in a gas atmosphere containing an organic compound such as helium or acetone, and the gas atmosphere is limited. Furthermore, helium is industrially disadvantageous because it is expensive, and when an organic compound is contained, the organic compound itself often reacts with the object to be treated, and the desired surface modification treatment cannot be performed. There is.

Further, the conventional method has a disadvantage that the processing speed is slow and disadvantageous for an industrial process. In addition, when a plasma-polymerized film is formed, the film decomposition speed is faster than the film formation speed, and high quality oxidation is performed. There was a problem that a film could not be obtained.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and in the production of an oxide film as an interlayer insulating film in the production process of a semiconductor device, a uniform plasma is continuously generated under a pressure near atmospheric pressure. An object of the present invention is to provide a method and an apparatus for easily manufacturing a high-quality oxide film by using a method for forming an oxide film on a substrate to be processed.

[0008]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, have combined a plasma CVD method capable of realizing a stable discharge state under atmospheric pressure conditions with a simple atmosphere control mechanism. As a result, the present inventors have found that a stable oxide film can be easily formed even at a high temperature, thereby completing the present invention.

That is, according to a first aspect of the present invention, in the formation of an oxide film in a semiconductor device by a plasma CVD method, a solid dielectric is formed on at least one of the opposing surfaces of a pair of opposing electrodes under a pressure near atmospheric pressure. Is installed, the plasma obtained by applying a pulsed electric field by introducing a processing gas between the pair of counter electrodes is brought into contact with the base material,
In addition, the vicinity of the contact portion between the plasma and the base material is nitrogen, argon, helium, neon, xenon, the atmosphere of one or more selected from the group consisting of dry air, a semiconductor element characterized by the above-mentioned. It is a manufacturing method.

Further, according to a second aspect of the present invention, the vicinity of the contact portion between the plasma and the substrate is nitrogen,
The method of manufacturing a semiconductor device according to the first aspect, wherein the atmosphere is maintained in at least one atmosphere selected from the group consisting of argon, helium, neon, xenon, and dry air.

The third invention of the present invention has a gas exhaust mechanism around a contact portion between the plasma and the base material, and arranges a gas curtain mechanism around the contact portion. 3. The semiconductor device according to the first or second aspect, wherein the vicinity of the contact portion is maintained in at least one atmosphere selected from the group consisting of nitrogen, argon, helium, neon, xenon, and dry air. Is the way.

[0012] A fourth aspect of the present invention is to provide a plasma treatment by performing a treatment in a container filled with at least one selected from the group consisting of nitrogen, argon, helium, neon, xenon, and dry air. The semiconductor device according to the first invention, wherein the vicinity of the contact portion with the substrate is maintained in an atmosphere of at least one selected from the group consisting of nitrogen, argon, helium, neon, xenon, and dry air. It is a manufacturing method of.

[0013] The fifth invention of the present invention is directed to a plasma processing apparatus and a plasma processing method, wherein at least one selected from the group consisting of nitrogen, argon, helium, neon, xenon and dry air is constantly supplied into a container. Nitrogen near the contact area with
The method for manufacturing a semiconductor device according to the fourth aspect, wherein the atmosphere is maintained in at least one kind of atmosphere selected from the group consisting of argon, helium, neon, xenon, and dry air.

According to a sixth aspect of the present invention, there is provided a method of manufacturing a semiconductor device according to any one of the first to sixth aspects, wherein the processing gas contains oxygen gas at 4% by volume or more. is there.

According to a seventh aspect of the present invention, the pulse-shaped electric field has a pulse rise and / or fall time of 100 μs or less and an electric field intensity of 0.5 to 250 kV / cm.
A method for manufacturing a semiconductor device according to any one of the first to sixth inventions, characterized in that:

According to an eighth aspect of the present invention, the pulsed electric field has a frequency of 0.5 to 100 kHz and a pulse duration of 1 to 1000 μs.
A method for manufacturing a semiconductor device according to any one of the above aspects.

A ninth aspect of the present invention is directed to a plasma C
In an apparatus for forming an oxide film in a semiconductor element by a VD method, a pair of counter electrodes having a solid dielectric disposed on at least one of the opposing surfaces, a mechanism for introducing a processing gas between the pair of counter electrodes, and a gap between the electrodes A mechanism for applying a pulsed electric field, a mechanism for bringing the plasma obtained by the pulsed electric field into contact with the substrate, and a portion near the contact portion between the plasma and the substrate comprising nitrogen, argon, helium, neon, xenon, and dry air. An apparatus for manufacturing a semiconductor device, comprising a mechanism for maintaining an atmosphere of one or more selected from a group.

Further, according to a tenth aspect of the present invention, the vicinity of the contact portion between the plasma and the base material is nitrogen,
The semiconductor device manufacturing apparatus according to the ninth aspect, characterized in that the apparatus is a mechanism for maintaining an atmosphere of at least one selected from the group consisting of argon, helium, neon, xenon, and dry air.

According to an eleventh aspect of the present invention, a gas exhaust mechanism is provided around a contact portion between a plasma and a substrate, and a gas curtain mechanism is disposed around the gas exhaust mechanism. The semiconductor device according to the ninth or tenth aspect, wherein the vicinity of the contact portion is a mechanism for maintaining at least one atmosphere selected from the group consisting of nitrogen, argon, helium, neon, xenon, and dry air. Manufacturing equipment.

A twelfth aspect of the present invention provides a container filled with at least one selected from the group consisting of nitrogen, argon, helium, neon, xenon, and dry air, wherein at least one of the opposing surfaces is solid. A pair of opposed electrodes provided with a dielectric, a mechanism for introducing a processing gas between the pair of opposed electrodes, a mechanism for applying a pulsed electric field between the electrodes, and a plasma obtained by the pulsed electric field By placing a mechanism for contacting the substrate with the substrate, the vicinity of the contact portion between the plasma and the substrate was maintained in an atmosphere of at least one selected from the group consisting of nitrogen, argon, helium, neon, xenon, and dry air. An apparatus for manufacturing a semiconductor device according to the ninth aspect, characterized in that the semiconductor element is manufactured.

According to a thirteenth aspect of the present invention, a plasma and a substrate are provided by constantly supplying at least one selected from the group consisting of nitrogen, argon, helium, neon, xenon and dry air into a container. A twelfth aspect of the present invention is characterized in that the vicinity of the contact portion is kept at at least one atmosphere selected from the group consisting of nitrogen, argon, helium, neon, xenon, and dry air. Is a semiconductor device manufacturing apparatus.

According to a fourteenth aspect of the present invention, the mechanism for bringing the plasma into contact with the base material is such that the plasma generated between the opposed electrodes is directed toward the base material through the solid dielectric having the gas outlet nozzle. An apparatus for manufacturing a semiconductor device according to any one of the ninth to thirteenth aspects, wherein the apparatus is manufactured.

According to a fifteenth aspect of the present invention, there is provided a semiconductor device according to the fourteenth aspect, further comprising a nozzle body standby mechanism for moving the gas outlet nozzle onto the surface of the base material after the preliminary discharge. Manufacturing equipment.

The sixteenth invention of the present invention is directed to the ninth to the ninth inventions.
A semiconductor device manufacturing apparatus comprising: the apparatus according to any one of the fifth aspects of the present invention; and a substrate transport mechanism.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The method and apparatus for forming an oxide film for manufacturing a semiconductor device by a plasma CVD method according to the present invention provide a method of forming a solid dielectric film on at least one of opposing surfaces of a pair of electrodes under a pressure near atmospheric pressure. A body is installed, a processing gas is introduced between the pair of opposed electrodes, and a pulsed electric field is applied between the electrodes, whereby a plasma of the obtained gas is brought into contact with the base material, and the base material is placed on the base material. A method for forming an oxide film, and wherein the vicinity of a contact portion between the plasma and the substrate is at least one gas selected from the group consisting of nitrogen, argon, helium, neon, xenon, and dry air (hereinafter, referred to as It is a method and apparatus characterized by being maintained in an atmosphere. Hereinafter, the present invention will be described in detail.

The pressure under the atmospheric pressure is defined as 1.333.
× 10 ^{4 to} 10.664 × 10 ⁴ Pa.
Above all, pressure adjustment is easy and the device is simple 9.33
The range of 1 × 10 ^{4 to} 10.297 × 10 ⁴ Pa is preferable.

It is known that under a pressure near the atmospheric pressure, except for a specific gas such as helium, ketone, etc., the plasma discharge state is not stably maintained and an instantaneous transition to the arc discharge state occurs. It is considered that by applying the applied electric field, a cycle of stopping the discharge before starting the arc discharge and restarting the discharge is realized.

Under pressure near atmospheric pressure, the method of applying a pulsed electric field of the present invention
It is possible to stably generate discharge plasma in an atmosphere that does not contain a component that takes a long time from a plasma discharge state such as helium to an arc discharge state.

According to the method of the present invention, glow discharge plasma can be generated regardless of the type of gas existing in the plasma generation space. In the atmospheric pressure plasma treatment under a specific gas atmosphere as well as the plasma treatment under the known low pressure condition, it is essential to perform the treatment in a closed vessel shielded from the outside air. According to the processing method, the processing can be performed in an open system or a low airtight system that prevents free flow of gas.

Furthermore, since a high-density plasma state can be realized by processing at atmospheric pressure, it has great significance in performing a semiconductor element manufacturing process such as continuous processing. The realization of the high-density plasma state involves two functions of the present invention.

First, the electric field strength is 0.5 to 250 kV /
By applying a pulsed electric field having a steep rise of 100 cm or less and a rise time of 100 cm or less, gas molecules existing in the plasma generation space are efficiently excited. Applying a pulsed electric field with a slow rise corresponds to the stepwise application of energies with different magnitudes.First, the excitation of molecules that ionize with low energy, that is, molecules with a small first ionization potential, takes precedence. When the next higher energy is applied, already ionized molecules are excited to a higher level, and it is difficult to efficiently ionize molecules existing in the plasma generation space. On the other hand, according to a pulse electric field having a rise time of 100 μs or less, energy is simultaneously applied to molecules existing in the space, and the absolute number of ionized molecules in the space is large,
That is, the plasma density is high.

Second, since a plasma in a gas atmosphere other than helium can be stably obtained, a molecule having more electrons than helium, that is, a molecule having a higher molecular weight than helium is selected as an atmosphere gas, and as a result, the electron density is reduced. This is the effect of realizing a high space. In general, molecules having many electrons are easier to ionize. As described above, helium is a component that is difficult to ionize. However, once it is ionized, it does not lead to an arc and remains in a glow plasma state for a long time, so it has been used as an atmospheric gas in atmospheric pressure plasma. However, if it is possible to prevent the discharge state from shifting to an arc, using molecules that are easily ionized and have a large mass number can increase the absolute number of molecules in the ionized state in space and increase the plasma. Density can be increased. In the prior art, it is impossible to generate glow discharge plasma in an atmosphere other than in an atmosphere in which helium is present at 90% or more. 4
Although it is disclosed in JP-A-74525, it is not possible to perform stable and high-speed processing at a practical level according to additional tests by the present inventors. Also, since acetone is contained in the atmosphere, treatments other than for the purpose of hydrophilicity are disadvantageous.

As described above, the present invention is stable only in an atmosphere in which molecules having more electrons than helium are present in excess, specifically, in an atmosphere containing 10% by volume or more of a compound having a molecular weight of 10 or more. It enables glow discharge, thereby realizing a high-density plasma state advantageous for surface treatment.

As the source gas for forming an oxide film of the present invention, for example, a silane-based gas such as SiH ₄ or Si ₂ H ₆ ;
An oxide film such as SiO ₂ or silicate glass can be obtained using a silane-containing gas such as an alkoxysilane-based gas such as tetraethoxysilane or TEOS and an oxygen-containing gas such as O ₂ , O ₃ , or dry air. Further, trimethyl phosphate (TMP), trimethyl borate (TM)
B) Addition of phosphine (PH ₃ ), diborane (B ₂ H ₆ ) to form an oxide film such as phosphorus silicate glass (PSG), boron silicate glass (BSG), boron phosphorus silicate glass (BPSG), etc. Can be.

In the present invention, the raw material gas may be used as it is as a processing gas. However, from the viewpoints of economy and safety, the raw material gas may be diluted with a diluent gas and used as a processing gas. Examples of the diluting gas include rare gases such as neon, argon, and xenon, and nitrogen gas. These may be used alone or in combination of two or more. Conventionally, at a pressure near the atmospheric pressure, processing in the presence of helium has been performed, but according to the method of applying a pulsed electric field of the present invention, as described above, compared to helium Stable processing is possible in inexpensive argon or nitrogen gas.

The mixing ratio between the source gas and the diluent gas in the processing gas is appropriately determined depending on the type of the diluting gas used, and the concentration of the silane-containing gas is from 0.01 to 0.01% in the processing gas.
5% by volume, more preferably 0.1% by volume.
２2% by volume. Further, the concentration of the oxygen-containing gas in the processing gas is preferably 4% by volume or more, more preferably 5 to 85% by volume.

Conventionally, at a pressure near the atmospheric pressure, the treatment has been carried out in an atmosphere in which helium is present in a large excess. However, according to the method of the present invention, argon and nitrogen are less expensive than helium. And the like, and the ratio of the source gas (oxygen) can be increased as compared with the case where helium is used. Furthermore, by instantaneously turning on the power, a high-density plasma state can be realized, and the processing speed can be increased.

Examples of the above-mentioned electrode include those made of a single metal such as copper and aluminum, alloys such as stainless steel and brass, and intermetallic compounds. The counter electrode is
In order to avoid occurrence of arc discharge due to electric field concentration, it is preferable that the distance between the opposed electrodes is substantially constant. Examples of an electrode structure that satisfies this condition include a parallel plate type, a cylindrical opposed plate type, a spherical opposed plate type, a hyperboloid opposed plate type, and a coaxial cylindrical type structure.

In addition, other than a substantially constant structure, a cylindrically opposed cylindrical type having a large cylindrical curvature can be used as a counter electrode because the degree of electric field concentration causing arc discharge is small. The curvature is preferably at least 20 mm in radius. Although it depends on the dielectric constant of the solid dielectric, at a curvature smaller than that, arc discharge due to electric field concentration tends to concentrate. If the respective curvatures are greater than this, the curvatures of the opposing electrodes may be different. The larger the curvature, the closer to the flat plate, the more stable the discharge can be obtained. Therefore, the radius is more preferably 40 mm or more.

Further, it is sufficient that at least one of the pair of electrodes for generating plasma has a solid dielectric disposed thereon, and even if the pair of electrodes are opposed to each other at an appropriate distance so as not to cause a short circuit. Well, they may be orthogonal.

The solid dielectric is provided on one or both of the opposing surfaces of the electrodes. At this time, it is preferable that the solid dielectric and the electrode on the side to be installed are in close contact with each other and completely cover the opposing surface of the contacting electrode. This is because if there is a portion where the electrodes directly face each other without being covered by the solid dielectric, an arc discharge is likely to occur therefrom.

The solid dielectric may be in the form of a sheet or a film, and preferably has a thickness of 0.01 to 4 mm. If it is too thick, a high voltage may be required to generate discharge plasma, and if it is too thin, dielectric breakdown may occur when a voltage is applied, and arc discharge may occur. As the shape of the solid dielectric, a container type can be used.

Examples of the material of the solid dielectric include plastics such as polytetrafluoroethylene and polyethylene terephthalate; glass; metal oxides such as silicon dioxide, aluminum oxide, zirconium dioxide and titanium dioxide; and double oxides such as barium titanate. And those obtained by layering them.

In particular, it is preferable that the solid dielectric has a relative dielectric constant of 2 or more (the same applies under a 25 ° C. environment). Specific examples of the dielectric having a relative dielectric constant of 2 or more include polytetrafluoroethylene, glass, and a metal oxide film. In order to stably generate a high-density discharge plasma, it is preferable to use a fixed dielectric having a relative dielectric constant of 10 or more. Although the upper limit of the relative permittivity is not particularly limited, about 18,500 of actual materials are known. As a solid dielectric having a relative dielectric constant of 10 or more, for example, a metal oxide film mixed with 5 to 50% by weight of titanium oxide and 50 to 95% by weight of aluminum oxide, or a metal oxide film containing zirconium oxide It is preferable to use a film having a thickness of 10 to 1000 μm.

The distance between the electrodes is determined by the thickness of the solid dielectric,
It is appropriately determined in consideration of the magnitude of the applied voltage, the purpose of utilizing the plasma, and the like, and is preferably 1 to 50 mm. If it is less than 1 mm, it may not be sufficient to place the electrodes at intervals. If it exceeds 50 mm, it is difficult to generate uniform discharge plasma.

The pulse electric field of the present invention will be described. FIG. 1 shows an example of a pulse voltage waveform. The waveforms (a) and (b) are impulse waveforms, the waveform (c) is a pulse waveform, and the waveform (d) is a modulation waveform. Although FIG. 1 shows a case where the voltage application is repeated positive and negative, a pulse of a type that applies a voltage to either the positive or negative polarity side may be used. Also,
A pulse electric field on which a direct current is superimposed may be applied. The waveform of the pulse electric field in the present invention is not limited to the above-mentioned waveforms, and may be modulated using pulses having different pulse shapes, rise times, and frequencies. Such modulation is suitable for performing high-speed continuous surface treatment.

The rise and / or fall time of the pulse electric field is preferably 100 μs or less. 100μ
If s exceeds s, the discharge state is likely to shift to an arc and becomes unstable, making it difficult to maintain a high-density plasma state due to a pulsed electric field. Further, the shorter the rise time and the fall time, the more efficiently the gas is ionized during the generation of plasma, but it is actually difficult to realize a pulse electric field with a rise time of less than 40 ns. More preferably, it is 50 ns to 5 μs. Here, the rise time refers to the time during which the voltage change is continuously positive, and the fall time refers to the time during which the voltage change is continuously negative.

It is preferable that the fall time of the pulse electric field is also steep.
It is preferable that the time scale is less than μs. Although it depends on the pulsed electric field generation technology, it is preferable that the rise time and the fall time can be set to the same time.

The electric field strength of the pulse electric field is 0.5 to 2
It is preferable that the pressure be 50 kV / cm. If the electric field strength is less than 0.5 kV / cm, it takes too much time for the treatment, and if it exceeds 250 kV / cm, arc discharge is likely to occur.

The frequency of the pulse electric field is 0.5 to 10
Preferably, it is 0 kHz. If the frequency is less than 0.5 kHz, the plasma density is low, so that it takes too much time for the treatment,
If it exceeds 100 kHz, arc discharge is likely to occur. More preferably, the frequency is 1 to 100 kHz. By applying such a high-frequency pulsed electric field, the processing speed can be greatly improved.

It is preferable that one pulse duration in the above-mentioned pulse electric field is 1 to 1000 μs. If the time is less than 1 μs, the discharge becomes unstable,
If it exceeds 000 μs, it is easy to shift to arc discharge.
More preferably, it is 3 to 200 μs. Here, one pulse duration is shown in FIG. 1 as an example,
In a pulsed electric field consisting of repetition of ON and OFF,
It refers to the continuous ON time of one pulse.

Examples of the treated base material of the present invention include:
Semiconductor wafer of silicon, GaAs, InP, etc., LC
A glass substrate for D, a plastic film such as PET or polyimide, a plastic plate, a glass plate and the like can be mentioned.
In addition, it can be applied to formation of a process oxide film for electronic parts.

Means for bringing the plasma into contact with the base material include, for example, (1) a method in which the base material is arranged in a discharge space of the plasma generated between the facing electrodes, and the plasma is brought into contact with the base material. 2) There is a method (gun type) in which plasma generated between opposing electrodes is brought into contact with a substrate placed outside the discharge space so as to be guided toward the substrate.

A specific method of the above (1) is a method in which a base material is placed between parallel plate type electrodes coated with a solid dielectric and brought into contact with plasma, and an upper electrode having a large number of holes is used. , A method of treating with a shower-like plasma, a method of running a film-like substrate in a discharge space, providing a container-like solid dielectric having an outlet nozzle on one electrode,
A method in which plasma is sprayed from the nozzle onto a substrate disposed on another electrode, and the like.

As a specific method of the above (2),
The solid dielectric is extended to form a plasma induction nozzle, such as a method of spraying toward a substrate disposed outside the discharge space, a parallel plate electrode and a long nozzle,
A combination of a coaxial cylindrical electrode and a cylindrical nozzle can be used. The material at the tip of the nozzle does not necessarily need to be the above-mentioned solid dielectric, and may be a metal or the like as long as it is insulated from the above-mentioned electrodes.

Among these, the method of spraying the plasma generated between the opposed electrodes onto the substrate through the solid dielectric having the gas outlet nozzle is such that the substrate, which is the object to be formed, is directly exposed to the high-density plasma space. This is a preferable method in which a gas in a plasma state is transported only to a target portion on the surface of the base material and a thin film can be formed, so that the electrical and thermal load on the base material is reduced.

In the formation of an oxide film by the plasma treatment of the present invention, the substrate temperature is preferably set to 80 to 400 ° C.
More preferably, it is 150 to 250 ° C.

In the formation of an oxide film by the plasma treatment according to the present invention, the substrate and the film may be humid air in the atmosphere in order to prevent oxidation of the substrate surface before film formation and to improve the film quality of the formed oxide film. In order to prevent contact with other impurities, the treatment needs to be performed in an inert gas atmosphere. Further, it is preferable to form an oxide film on the base material in a state where the plasma is stable.

Therefore, the apparatus of the present invention includes, in addition to the apparatus for forming an oxide film by bringing the plasma into contact with the base material,
It is necessary to provide an apparatus having a mechanism for maintaining the vicinity of the contact portion between the plasma and the substrate in an inert gas atmosphere.

In the present invention, as a mechanism for maintaining the vicinity of the contact portion between the plasma and the substrate in an inert gas atmosphere, a gas curtain mechanism using an inert gas, a mechanism performing processing in a container filled with an inert gas, and the like. Is mentioned.

As a means for transporting the substrate, if the substrate is in the form of a film, a transport system comprising a feeding roll and a winding roll is used.
A transfer system such as a transfer conveyor and a transfer robot can be used.

As the gas curtain mechanism using the inert gas, a gas exhaust mechanism is provided around the contact portion between the plasma and the base material, and a gas curtain mechanism using the inert gas is provided around the gas exhaust mechanism. The vicinity of the contact portion with the substrate can be kept in an inert gas atmosphere.

The method and apparatus of the present invention will be specifically described with reference to the drawings. FIG. 2 shows a device that uses a coaxial cylindrical nozzle and maintains the vicinity of the contact portion between the plasma and the substrate in an atmosphere of an inert gas or the like by a gas curtain mechanism, and has a gas exhaust mechanism around the contact portion. An example of an apparatus having a device for spraying plasma onto a substrate using a device having a shower function of an inert gas or the like in which a gas curtain mechanism is provided around the gas exhaust mechanism, and a device for transporting the substrate. FIG.
In FIG. 2, 1 is a power source, 2 is an outer electrode, 3 is an inner electrode, 4 is a solid dielectric, 5 is a gas outlet, 6 is a nozzle body having a coaxial cylindrical nozzle, 7 is a processing gas inlet, 1
0 is an inner exhaust gas cylinder, 11 is an outer exhaust gas cylinder, 12 is an inlet for an inert gas or the like, 13 is a pore for blowing an inert gas or the like, 14 is a substrate, 41 is a carry-in belt, and 42 is a processing unit. A belt 43 represents a carry-out belt.

For example, the processing gas is introduced into the cylindrical solid dielectric container from the gas inlet 7 in the direction of the white arrow, and the electrode 2 disposed outside the cylindrical solid dielectric container and the cylindrical solid dielectric container. By applying a pulsed electric field between the inner electrode 3 disposed inside the body container and the pulsed electric field, the gas is blown out from the outlet 5 as plasma gas, and is mainly sucked and collected from the inner peripheral exhaust gas cylinder 10. On the other hand, the base material 14 is first carried by the carry-in belt 41, and then carried by the processing unit belt 42, and the plasma gas is blown from the gas outlet,
The oxide film is formed and then conveyed through three conveying steps of being carried out by the carry-out belt 43. In addition, the inert gas or the like is introduced from the inlet 12 for the inert gas or the like, and is blown toward the base material 14 conveyed from the blowout hole 13 for the inert gas or the like at the bottom, and serves as a gas curtain. Then, the atmosphere of the substrate 14 is maintained at an atmosphere of an inert gas or the like. The inert gas and the like are mainly collected from the outer exhaust gas cylinder 11. The thickness of the deposited film can be controlled by using a transport belt whose feed speed can be adjusted arbitrarily. Further, the processing section belt preferably has a heating mechanism.

FIG. 3 shows a device that uses a parallel plate-type long nozzle and maintains the vicinity of the contact portion between the plasma and the substrate in an atmosphere of an inert gas or the like by a gas curtain mechanism. It has an exhaust mechanism, and further includes a device for blowing plasma to the substrate using a device having a shower function of an inert gas or the like in which a gas curtain mechanism is disposed around the gas exhaust mechanism, and a transport mechanism for the substrate. It is a figure showing an example of a device provided. 1 is a power supply, 2 is an electrode, 3 is an electrode, 4 is a solid dielectric, 5 is a gas outlet, 7 is a processing gas inlet, 10
Is an inner exhaust gas cylinder, 11 is an outer exhaust gas cylinder, 12 is an inlet for an inert gas or the like, 13 is a pore for blowing out an inert gas or the like, 14 is a base material, 41 is a carry-in belt, and 42 is a processing unit belt. , 43 denote carry-out belts, respectively.

In FIG. 3, for example, the processing gas is introduced into the box-shaped solid dielectric container from the gas inlet 7 in the direction of the outlined arrow, and the electrode 2 and the electrode 2 arranged outside the box-shaped solid dielectric container are introduced. By applying a pulsed electric field between the inner exhaust gas cylinder 3 and the inner exhaust gas cylinder 10, the plasma gas is blown out from the outlet 5 and is mainly collected by suction. On the other hand, substrate 1
Reference numeral 4 denotes a three-step conveyance in which the carrier gas is first carried by the carry-in belt 41, then carried by the processing unit belt 42, the plasma gas is blown from the gas outlet, an oxide film is formed, and then carried out by the carry-out belt 43. It is transported through the process. In addition, the inert gas or the like is introduced from the inlet 12 for the inert gas or the like, and is blown toward the base material 14 conveyed from the blowout hole 13 for the inert gas or the like at the bottom, and serves as a gas curtain. Then, the atmosphere of the substrate 14 is maintained at an atmosphere of an inert gas or the like. The inert gas and the like are mainly collected from the outer exhaust gas cylinder 11. The transport belt is
By using a material that can arbitrarily adjust the feed speed, the thickness of the deposited film can be controlled. Further, the processing section belt preferably has a heating mechanism.

It is preferable that the apparatus having a shower function of inert gas or the like has a bottom surface as shown in FIGS.

FIG. 4 shows a shower device for an inert gas or the like when a coaxial cylindrical nozzle is used, and corresponds to the bottom surface of the nozzle portion in FIG. The plasma gas is supplied to the gas outlet 5
After forming an oxide film on the base material, it is mainly discharged from the inner peripheral exhaust gas cylinder 10. Further, the inert gas or the like is blown out from the blowing holes 13 of the inert gas or the like existing in the shower region of the inert gas or the like, and is mainly discharged from the outer exhaust gas cylinder 11.

FIG. 5 shows a shower device for an inert gas or the like in the case of using a parallel-plate long nozzle, which corresponds to the bottom surface of the nozzle portion in FIG. The plasma gas is blown out from the gas blowout port 5, and after forming an oxide film on the base material, is mainly discharged from the inner peripheral exhaust gas cylinder 10. Further, the inert gas or the like is blown out from the blowing holes 13 of the inert gas or the like existing in the shower region of the inert gas or the like, and is mainly discharged from the outer exhaust gas cylinder 11.

In the present invention, as a mechanism for maintaining the vicinity of the contact portion between the plasma and the substrate in an atmosphere of an inert gas or the like, a method of performing the treatment in a container filled with an inert gas or the like is provided. The device shown in FIG.

In the apparatus shown in FIG. 6, an oxide film is formed in a container 30 filled with an inert gas or the like. For example, a container 3 such as an inert gas provided with a loading / unloading chamber 31 for using the substrate transfer robot 20 and a shutter 32 therefor.
It is preferable to use a device in which the main portion near the contact portion between the plasma and the base material is housed at 0. In FIG. 6, it is only necessary to always supply the inert gas or the like to the container 30 for the inert gas or the like in the direction of the arrow, there is no need for airtightness, no vacuum pump is required, and a simple blower-type exhaust fan is sufficient. Further, the pressure resistance of the container 30 itself such as an inert gas is not required, and a simple chamber may be used. In the film forming apparatus housed in a container such as an inert gas, a processing gas is introduced into a plasma gas nozzle body 6 having an XYZ moving mechanism from a direction of a white arrow, and is sprayed on a substrate 14 to form an oxide film. Let it form. Also,
The exhaust gas is exhausted from the exhaust gas cylinder 10. The base material 14
Is transferred into and out of the cassette 21 in the transfer chamber 31 by the transfer robot 20. The product after the formation of the oxide film is taken in and out through the shutter 32. Here, as the nozzle body 6, one provided with a container-shaped solid dielectric having an outlet nozzle on one electrode (detailed drawing 2) or one provided with a parallel plate-type long nozzle (detailed drawing 3)
And so on.

Further, in the case of using a gun-type plasma generator in which the solid dielectric has a gas outlet nozzle,
Suppress the occurrence of defective products by using a plasma generation mechanism that has a nozzle body standby mechanism that moves the gas outlet nozzle to the base material surface after performing preliminary discharge from the start of voltage application to the electrode until the discharge state is stabilized Can be. FIG. 7 schematically shows the apparatus.

In FIG. 7, the processing gas is introduced into the nozzle body 6 and the plasma is blown onto the substrate 14.
The nozzle body 6 stands by at the position A during the preliminary discharge until the discharge state is stabilized, and after the discharge state is stabilized, the substrate 14
The surface is moved to a position B where an oxide film is to be formed, and the deposition of the oxide film is started. In this device, the support 1
By providing a ring-shaped hood 10 surrounding 5
The processing gas can be evacuated, and the transfer robot 20 is additionally provided so that the wafer base material 14 can be taken in and out of the wafer cassette 21 to efficiently form an oxide film on the base material. The nozzle body standby mechanism can be used together with an XYZ moving device for sweeping the nozzle body. Further, the apparatus shown in FIG. 7 can be housed in the container 30 filled with the inert gas shown in FIG.

In the atmospheric pressure discharge using the pulse electric field according to the present invention, the discharge can be generated directly between the electrodes under the atmospheric pressure without depending on the kind of gas at all, and a more simplified electrode structure, Atmospheric pressure plasma device by discharge procedure,
In addition, high-speed processing can be realized with a processing method.
Further, parameters related to the formation of the oxide film can be adjusted by parameters such as a pulse frequency, a voltage, and an electrode interval.

The method of manufacturing an oxide film according to the present invention comprises an IC circuit,
The present invention can be applied to the manufacture of other semiconductor devices such as a solar cell and a switch device of a liquid crystal display.

[0076]

EXAMPLES The present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

Example 1 A substrate 14 (GaAs wafer,
It was deposited a SiO ₂ film to a diameter 75 mm) on. In the parallel plate opposed type long nozzle, a solid dielectric 4 made of alumina is sprayed on electrodes 2 and 3 made of aluminum. The discharge gap (the distance between opposing dielectrics) is adjusted to 1 mm.

As a processing gas, a mixed gas of 0.16% of tetraethoxysilane and 16% of oxygen diluted with argon was introduced from the gas inlet 7 in the direction of a white arrow, and the electrode 2
A pulse electric field having a pulse waveform shown in FIG. 1 (a), a pulse rising / falling speed of 5 μs, and a voltage of 10 kV was applied between the cells and 3, and discharged at 95 kPa (atmospheric pressure) to generate plasma. The GaAs wafer 14 on which the SiO ₂ film is to be applied is sent in the direction of the arrow by the carry-in belt 41. An SiO ₂ film is deposited on the GaAs wafer 14 while passing through the plasma gas outlet 5 on the processing unit belt 42 via the N ₂ gas shower blown out from the outlet pores 13. After that, it is again carried out by the carry-out belt 43 via the N ₂ gas shower. The deposition rate of the SiO ₂ film on a GaAs wafer having a diameter of 75 mm was about 1.3 μm / min (transport speed 500 mm / min).

The waste gas of the plasma gas is supplied to the exhaust gas cylinder 10.
Is discharged from Also, N₂Waste gas from gas shower
Is mainly collected and discharged from the outer exhaust pipe 11. Ma
The SiO₂Processing unit belt 42 located at the place where
Is kept at a temperature of 200 ° C.₂At the time of film deposition
The substrate (GaAs wafer) is heated. N ₂Gassi
By the power mechanism, SiO₂GaAs way before film deposition
Ha is N₂Oxidation of the surface because it is kept in a gas atmosphere
Is suppressed, and the SiO₂-GaAs interface
No metamorphosis.

Comparative Example 1 In Example 1, the applied electric field was 150 MHz s.
Except that in-wave was used, 0.16% of tetraethoxysilane and 16% of oxygen were mixed and used as processing gases, and helium was used as a diluting gas, as in Example 1,
A SiO ₂ thin film was formed on a polyimide film.
Although the formation of the SiO ₂ thin film was confirmed, the film formation rate was 0.26 μm / min.

Comparative Example 2 The same apparatus as in Example 1 was used.
Using a 56 MHz, 200 W sin wave electric field condition,
An SiO ₂ thin film was formed on a polyimide film in the same manner as in Example 1, except that an oxide film was formed under an environment of 13 Pa. Although the formation of the SiO ₂ thin film was confirmed, the film formation rate was 0.08 μm / min.

EXAMPLE 2 Using the apparatus shown in FIG. 3, a gas obtained by diluting 0.20% of tetraethoxysilane and 10% of oxygen with argon gas as a processing gas under the same conditions as in Example 1 under atmospheric pressure. A pulse electric field was applied, and a film was formed on the stainless steel substrate from the nozzle port 5. Generation of a SiO ₂ thin film on a stainless steel substrate was confirmed. At this time, the deposition rate was 1.0 μm /
Minutes.

[0083]

According to the method of manufacturing a semiconductor device for forming an oxide film to which a pulsed electric field is applied according to the present invention, a plasma of a processing gas is brought into contact with a substrate near atmospheric pressure to form an oxide film on the surface of the substrate. Is formed under an atmosphere of an inert gas or the like,
The film formation process can be made a more efficient system,
It can contribute to improving the yield. Further, since the method of the present invention can be carried out under atmospheric pressure, it can be easily inlined, and by using the method of the present invention, a reduction in the speed of the entire treatment step can be prevented.

[Brief description of the drawings]

FIG. 1 is a voltage waveform diagram showing an example of a pulse electric field according to the present invention.

FIG. 2 is a view showing an example of an oxide film forming apparatus of the present invention.

FIG. 3 is a view showing an example of an oxide film forming apparatus of the present invention.

FIG. 4 is a bottom view of an example of a shower function device such as an inert gas used in the present invention.

FIG. 5 is a bottom view of an example of a shower function device such as an inert gas used in the present invention.

FIG. 6 is a view showing an example of an oxide film forming apparatus of the present invention.

FIG. 7 is a view showing an example of an oxide film forming apparatus of the present invention.

[Explanation of symbols]

 Reference Signs List 1 power supply (high-voltage pulse power supply) 2, 3 electrode 4 solid dielectric 5 gas outlet 6 nozzle body 7 gas inlet 10, 11 exhaust gas cylinder 12 inlet for inert gas, etc. 13 outlet for inert gas, etc. Reference Signs List 14 base material 15 support stand 20 transfer robot 21 cassette 22 arm 30 container 31 carry-in / out room 32 shutter 41 carry-in belt 42 processing unit belt 43 carry-out belt

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Koji Honma 2-703, Tateno, Higashiyamato-shi, Tokyo F-term in Chemitronics Inc. (reference) 4K030 AA06 AA16 AA18 BA44 CA04 CA12 FA01 KA30 5F045 AA08 AB32 AC01 AC07 AC11 AC15 AC16 AC18 AD04 AD05 AD06 AD07 AD08 AE23 AE25 AE29 AF03 AF04 AF07 AF08 CB04 CB05 DP22 EE12 EE14 EF02 EF05 EF10 EF20 EH04 EH05 EH08 EH12 EH13 EH19 5F058 BB01 BB02 BB06 BB07 BC02 BF07 BF23 BF23

Claims (16)

[Claims] In forming an oxide film in a semiconductor element by a plasma CVD method, a solid dielectric is provided on at least one of the opposing surfaces of a pair of electrodes facing each other under a pressure near atmospheric pressure, and the pair of opposing electrodes is formed. A plasma obtained by applying a pulsed electric field by introducing a processing gas therebetween is brought into contact with a substrate, and the vicinity of a contact portion between the plasma and the substrate is near nitrogen, argon, helium, neon, xenon,
A method for manufacturing a semiconductor device, wherein the atmosphere is maintained in at least one atmosphere selected from the group consisting of dry air. 2. The gas curtain mechanism ensures that the vicinity of the contact portion between the plasma and the substrate is maintained in an atmosphere of at least one selected from the group consisting of nitrogen, argon, helium, neon, xenon, and dry air. The method for manufacturing a semiconductor device according to claim 1, wherein: 3. A gas exhaust mechanism is provided around a contact portion between the plasma and the substrate, and a gas curtain mechanism is arranged around the gas exhaust mechanism.
3. The method according to claim 1, wherein the atmosphere is maintained in at least one atmosphere selected from the group consisting of argon, helium, neon, xenon, and dry air. 4. The process is performed in a vessel filled with at least one selected from the group consisting of nitrogen, argon, helium, neon, xenon, and dry air. , Argon, helium,
2. The method according to claim 1, wherein the atmosphere is maintained in at least one kind selected from the group consisting of neon, xenon, and dry air. 5. The container is constantly supplied with at least one selected from the group consisting of nitrogen, argon, helium, neon, xenon, and dry air, so that the vicinity of the contact portion between the plasma and the substrate is nitrogen or argon. 5. The method according to claim 4, wherein the atmosphere is kept at least one selected from the group consisting of helium, neon, xenon, and dry air. 6. The method according to claim 1, wherein the processing gas contains oxygen gas in an amount of 4% by volume or more. 7. The pulsed electric field according to claim 1, wherein the pulse rise and / or fall time is 100 μs or less, and the electric field intensity is 0.5 to 250 kV / cm. 3. The method for manufacturing a semiconductor device according to item 1. 8. A pulse-like electric field having a frequency of 0.5 to 1
The method of manufacturing a semiconductor device according to claim 1, wherein the pulse duration is 00 kHz and the pulse duration is 1 to 1000 μs. 9. An apparatus for forming an oxide film in a semiconductor device by a plasma CVD method, wherein a pair of opposing electrodes having a solid dielectric disposed on at least one opposing surface, and a processing gas introduced between the pair of opposing electrodes. Mechanism, a mechanism for applying a pulsed electric field between the electrodes, a mechanism for contacting a plasma obtained by the pulsed electric field with a substrate, and nitrogen, argon, helium, near the contact portion between the plasma and the substrate,
An apparatus for manufacturing a semiconductor device, comprising: a mechanism for maintaining an atmosphere of at least one selected from the group consisting of neon, xenon, and dry air. 10. A mechanism for maintaining the vicinity of a contact portion between a plasma and a base material in an atmosphere of at least one selected from the group consisting of nitrogen, argon, helium, neon, xenon, and dry air by a gas curtain mechanism. The apparatus for manufacturing a semiconductor device according to claim 9, wherein: 11. A gas exhaust mechanism is provided around a contact portion between the plasma and the base material, and a gas curtain mechanism is disposed around the gas exhaust mechanism so that the vicinity of the contact portion between the plasma and the base material becomes nitrogen, argon, helium. 11. The apparatus for manufacturing a semiconductor device according to claim 9, wherein the apparatus is a mechanism for maintaining an atmosphere of at least one selected from the group consisting of neon, xenon, and dry air. 12. Nitrogen, argon, helium, neon,
Xenon, a container filled with at least one selected from the group consisting of dry air, a pair of counter electrodes having a solid dielectric on at least one of the opposing surfaces, and a processing gas between the pair of counter electrodes. By providing a mechanism for introducing, a mechanism for applying a pulsed electric field between the electrodes, and a mechanism for bringing the plasma obtained by the pulsed electric field into contact with the substrate, the vicinity of the contact portion between the plasma and the substrate 10. The apparatus for manufacturing a semiconductor device according to claim 9, wherein the temperature is kept at least one selected from the group consisting of nitrogen, argon, helium, neon, xenon, and dry air. 13. A container comprising nitrogen, argon, helium,
The vicinity of the contact portion between the plasma and the substrate is selected from the group consisting of nitrogen, argon, helium, neon, xenon, and dry air by constantly supplying at least one selected from the group consisting of neon, xenon, and dry air. 13. The apparatus for manufacturing a semiconductor device according to claim 12, wherein the atmosphere is maintained in at least one kind of atmosphere. 14. A mechanism for bringing plasma into contact with a substrate,
The semiconductor device according to any one of claims 9 to 13, wherein plasma generated between the counter electrodes is guided toward the substrate through a solid dielectric having a gas outlet nozzle. manufacturing device. 15. The semiconductor device manufacturing apparatus according to claim 14, further comprising a nozzle body standby mechanism for moving the gas outlet nozzle onto the surface of the base material after the preliminary discharge. 16. An apparatus for manufacturing a semiconductor device, comprising: the apparatus according to claim 9; and a substrate transport mechanism.