JP2004107182A - Film deposition method and film deposition apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a film deposition method by which a uniform film can be efficiently deposited at a predetermined position by using laser, and a film deposition apparatus. <P>SOLUTION: In the film deposition method, a film of a reaction product is formed on the surface of a substrate by irradiating the surface of the substrate with a laser beam so as to heat the substrate and react raw material components while introducing the raw material components containing a gaseous substance in the direction of the substrate. It is preferable that the raw material components are introduced perpendicular to the substrate. The film deposition apparatus is equipped with a raw material introducing means including a vaporization unit, a film deposition chamber into which the raw material components are introduced through the raw material introducing means and in which the substrate is arranged, and a laser generating device for irradiating the substrate with laser, which is installed in the chamber. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a film forming method and a film forming apparatus, and more particularly, to a film forming method and a film forming apparatus capable of efficiently forming a uniform film at a predetermined position using a laser. INDUSTRIAL APPLICABILITY The film forming method and film forming apparatus of the present invention are useful for thin film manufacturing technology.
[0002]
[Prior art]
A general CVD method for forming a film is a method for producing a film of a metal, a metal oxide, a metal nitride, or the like. Usually, the substrate is heated in advance by a heater or the like, and the raw material is heated on the substrate surface by thermal excitation. It is intended to obtain a high-quality film of high purity by reacting components, and is widely used as a method for forming a film of a ferroelectric substance, a magnetic substance, or the like. In this method, since the raw material components react on the substrate surface, it is necessary to excite a chemical bond near the substrate surface by heat, plasma, or the like.
Further, as a CVD method using a laser, according to Patent Document 1, a laser beam is incident on a substrate surface directly in parallel with the substrate surface, and in a space directly above the substrate, raw material components are reacted by plasma excitation to form a film on the substrate. A forming technique is disclosed.
[0003]
[Patent Document 1]
JP-A-5-78847
[Problems to be solved by the invention]
It is an object of the present invention to provide a film forming method and a film forming apparatus capable of efficiently forming a uniform film at a predetermined position using a laser.
[0005]
[Means for Solving the Problems]
The present invention is described below.
[1] A method of forming a film on the surface of a substrate, wherein a laser beam is irradiated on the substrate surface while introducing a raw material component containing a gaseous substance in the direction of the substrate, and the substrate is heated and reacted by the reaction of the raw material component at the same time. A film forming method comprising forming a film made of a product.
[2] The film forming method according to [1], wherein the raw material components are introduced perpendicularly to the substrate.
[3] A raw material introducing means, a film forming chamber in which raw material components are introduced from the raw material introducing means and a substrate is disposed therein, and a film forming chamber disposed in the film forming chamber and irradiating the substrate with a laser. A film forming apparatus, comprising: a laser generator.
[4] The film forming apparatus according to [3], wherein the raw material introducing means includes a vaporizer.
[5] The vaporizer includes a gas-permeable porous container, heating means for heating the gas-permeable porous container, and gas supply means for supplying a predetermined gas into the gas-permeable porous container. 5. The film forming apparatus according to the above item 4.
[0006]
【The invention's effect】
According to the film forming method of the present invention, a film can be efficiently formed on the surface of a substrate. In particular, since the substrate surface can be instantaneously heated to the reaction temperature of the raw material components by using laser light, it is not necessary to provide a means for heating the substrate in the film forming apparatus itself, and a film can be formed in a short time. can do. When a predetermined position is irradiated with a laser beam, a patterned film can be formed. Further, when a raw material component containing a gaseous substance is introduced vertically to the substrate, the reaction product can be grown vertically to the substrate, and a uniform film can be obtained.
According to the film forming apparatus of the present invention, the above film forming method can be effectively achieved. In particular, when the raw material introduction means includes a vaporizer, the raw material components including the gaseous substance can be introduced toward the substrate without waste. In addition, by making this vaporizer a predetermined configuration, it is possible to efficiently vaporize a substance such as a sublimable substance without deteriorating inside the container, and to supply a constant amount of the sublimable substance for a long time. Can be. In addition, by using a gas-permeable porous container and gas supply means, substances such as sublimable substances are heated while always being in contact with a gas to be sent without being densely located. It can be vaporized efficiently in the flowing gas.
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
The present invention will be described in more detail.
The film forming method of the present invention is to irradiate a laser beam onto the substrate surface while introducing a raw material component containing a gaseous substance in the direction of the substrate, and simultaneously heat the substrate to form a film formed of a reaction product by the reaction of the raw material component on the substrate. It is formed on the surface.
The raw material component is composed of at least one kind containing a gaseous substance. The gaseous substance is not particularly limited as long as it reacts by itself or with other components by irradiation with laser light. For example, a vaporized substance (sublimation substance) of a material used as a raw material in a known CVD method may be used. In addition, the raw material component may be a particulate solid substance that is not a gas. Further, a gas having an action of promoting the formation of a film, for example, a gas containing oxygen gas, carbon monoxide gas, carbon dioxide gas, water vapor, or the like may be used.
[0008]
The raw material component is introduced in the direction of the substrate for forming a film on the surface of the substrate.At this time, when the raw material component is composed of a plurality of components, the raw material component may be introduced as a uniform mixture, Each component may be introduced separately. In addition, some or all of the raw material components may or may not be heated. When the gaseous substance in the raw material component is a vaporized compound, it is preferable that the gaseous substance remains in a gas state until the raw material component reaches the substrate direction. This makes it possible to form a film made of a reaction product having a high yield without side reactions.
Further, a component that reacts with the above-mentioned raw material component may be previously present on the substrate surface.
[0009]
The substrate is not particularly limited, but is preferably a substrate that is not deformed, decomposed, or degraded by the irradiated laser light. Examples include metals, alloys, and ceramics.
[0010]
When introducing the raw material components, it is preferable to introduce the raw material components perpendicularly to the substrate in order to form a uniform film on the surface of the substrate. Here, “vertical” is defined as follows. When the raw material component is one component, it is preferably 80 to 90 degrees, more preferably 85 to 90 degrees with respect to the substrate, but when the raw material component is composed of two or more components, it is close to 90 degrees. Since it is difficult to introduce, the range is preferably 60 to 85 degrees, more preferably 70 to 85 degrees.
[0011]
The laser light is applied to a predetermined position on the substrate surface. The laser beam to be irradiated may be selected in consideration of the reactivity of the raw material components, and is not particularly limited. Usually, a long-wavelength laser such as a YAG laser or a carbon dioxide laser is used. Further, an optical fiber may be used.
[0012]
The angle with respect to the substrate at the time of laser light irradiation is not particularly limited, and may be an oblique direction or an acute angle close to parallel. Also, if there is a through hole in the substrate mounting table for placing the substrate, the laser light is passed through the through hole on the back side of the substrate to form a film on the substrate that is thin and has good thermal conductivity. Irradiation can also be performed. In any case, in order to form a film at a predetermined position on the substrate surface more accurately, a preferable irradiation angle is 10 to 90 degrees, and more preferably 45 to 90 degrees. In order to form the film efficiently, the output and irradiation time of the laser beam, the volume of the chamber in which the substrate is placed, the type, concentration, and reactivity of the raw material components may be appropriately selected.
When the position of the substrate is fixed, laser light may be scanned in order to form a film with a large area or a predetermined pattern shape.
[0013]
The film forming apparatus according to the present invention includes a raw material introducing means, a film forming chamber in which raw material components are introduced from the raw material introducing means, and a substrate is disposed therein, and a laser disposed in the film forming chamber and having a laser on the substrate. And a laser generator for irradiating light.
[0014]
The raw material introduction means is not particularly limited as long as the raw material components can be efficiently supplied in the direction of the substrate in the film forming chamber. Further, a material that can be continuously supplied at a predetermined concentration is preferable. The supply rate of the raw material is not particularly limited, but may be arbitrarily selected in the range of usually 10 to 500 cm ³ / min, preferably 50 to 100 cm ³ / min.
It is preferable that the raw material introduction means according to the present invention be a means including a vaporizer. For example, it is possible to achieve a shorter path from vaporization to film formation by producing a gaseous substance contained in a raw material component by a vaporizer and introducing the obtained gaseous substance as it is or simultaneously with other components toward a substrate. it can.
[0015]
The vaporizer is not particularly limited, but it is preferable to vaporize or sublime by heating a substance to be vaporized (hereinafter, also referred to as “vaporizable substance”) while floating in a container. The container for storing the vaporizable substance is not particularly limited as long as the container does not lose the vaporizable substance during vaporization, that is, is not leaked to the outside during floating. Preferably, the portion other than the portion from which the vaporized substance is delivered is sealed.
The method of suspending the vaporizable substance is not particularly limited, and examples thereof include a method of circulating a gas in a container and a method of supplying a gas from the outside. Here, “floating” refers to a state where the contact area between adjacent particles is small due to the fact that the particles may flow so as to dance in the container, or the vaporizable substance in the container becomes bulky.
[0016]
Here, examples of the vaporizable substance will be described below. Metal chlorides such as zirconium chloride, yttrium chloride, silicon chloride, and aluminum chloride; and organometallic compounds such as β-diketonates such as metal alkoxides, phthalocyanines, metal dipivaloylmethane complexes, and metal acetylacetonates. The vaporizable substance is preferably a powder, and the particle size is not particularly limited.
[0017]
The means for heating the vaporizable substance is not particularly limited, and examples thereof include an induction heating method, an electric heating method, and an external heating method using a heater. Alternatively, the container may be placed in an electric furnace to heat the entire container. The heating temperature may be arbitrarily selected depending on the vaporization (sublimation) temperature of the vaporizable substance.
[0018]
The film is formed in a film forming chamber, and is usually a closed space. In addition to the above, the film forming apparatus of the present invention can further include a cooling device, a (vacuum) exhaust device, a gas introduction device, a substrate mounting base, a heater, a viewing window, and the like, as necessary. The above gas introduction device is used for the purpose of introducing a gas for reacting or promoting the reaction with the introduced raw material components, or for controlling the reactivity of the introduced raw material components, for adjusting the atmosphere, and the like. be able to. Each of the above means and devices may have a plurality.
[0019]
The configuration of the film forming apparatus of the present invention will be described with reference to the schematic diagram shown in FIG. The apparatus 1 includes a vaporizer 2 as a raw material introduction unit, a gas supply unit 3 for supplying a predetermined gas to the vaporizer 2, a raw material component supply port 4, and a film forming chamber 5 in which a substrate 10 is disposed. , A cooling device 6, a laser generator 7, an optical device (lens) 8, and an exhaust device 9. The pressure inside the film forming chamber 5 can be reduced by the exhaust device 9. Further, in order to efficiently promote the reaction on the surface of the substrate, the atmosphere of the film forming chamber 5 may be nitrogen gas, oxygen gas, carbon dioxide gas, water vapor, or the like. The outer peripheral portion of the film forming chamber 5 and the substrate mounting table can be cooled by a low-temperature gas or a low-temperature liquid supplied by the cooling device 6.
Laser light relating to the heating of the substrate 10 and the reaction of the raw material components is generated from the laser generator 7 and is irradiated into the film forming chamber 5 through the laser light introduction window. The laser light can be converged or diffused by the optical device 8 installed immediately before the laser light introduction window. Thereby, a predetermined position on the surface of the substrate 25 can be irradiated with the laser beam.
[0020]
The raw material components for forming the film are formed by separately or mixing a vaporized (sublimed) substance sent from the vaporizer 2 as a raw material introduction means and other gas components used as needed. It is introduced in the direction of the substrate 10 in the chamber 5.
The substrate 10 is held on a substrate mounting table. By providing a mechanism for moving, tilting, or rotating the substrate, the substrate mounting base can more efficiently obtain a film having a desired shape or property.
[0021]
By using a film forming apparatus as shown in FIG. 1, the film is formed by introducing a raw material component containing a vaporized (sublimated) substance sent from a vaporizer 2 toward a substrate, and applying a laser beam from a laser generator 7 to the substrate. Is formed by a reaction product generated on the substrate surface simultaneously with the heating of the substrate.
[0022]
Next, a specific embodiment of the vaporizer 2 will be described with reference to FIG. The vaporizer 2 includes gas supply means 3 for supplying a predetermined gas into the gas-permeable porous container 22, a holding container 21, a gas-permeable porous container 22 for containing a gaseous substance 23, A heating means 24 for heating the porous porous container 22 and a delivery pipe 25 for delivering a vaporized (sublimated) substance are provided. The gas permeable porous container 12 is usually placed in, for example, a fireproof holding container 21 or the like in order to hold or simply arrange it. The vaporizable substance 23 is gently and fluidly displaced by a gas (hereinafter, also referred to as a “carrier gas”) supplied from the gas supply unit 3 through a hole of the gas-permeable porous container 22, and is heated by the heating unit 24. At the same time, it vaporizes (sublimates), and the vaporized (sublimated) substance is delivered from the delivery pipe 25. The outer surface of the gas-permeable porous container 22 and the inner surface of the holding container 21 may be in close contact with each other, or may be separated from each other and have a gap. In order to efficiently vaporize (sublimate) and deliver the vaporizable substance 23, it is preferable to supply gas only from the bottom surface of the gas-permeable porous container 22. As a result, the vaporizable substance 23 floats by the carrier gas from below, and is efficiently vaporized (sublimated) without being transformed by heating.
[0023]
The gas-permeable porous container 22 is capable of passing gas and vaporized (sublimated) substances supplied by gas supply means, has pores communicating between the inside and the outside of the container, and is further deteriorated by heating. There is no particular limitation as long as it does not cause deterioration or the like, or does not react with the vaporizable substance. The constituent material is not particularly limited, and examples thereof include metals such as aluminum, zirconium, and platinum, alloys such as stainless steel, and ceramics such as alumina, zirconia, and silica.
The pore size of the pores is such that the vaporizable substance does not cause clogging and the like, and furthermore, it is sufficient that the vaporized (sublimated) substance can be efficiently passed therethrough, preferably 10 μm to 2 mm, more preferably 100 μm to 1 mm. And more preferably 200 to 500 μm.
[0024]
The carrier gas supplied by the gas supply means 3 is not particularly limited as long as it does not react with a vaporizable substance. For example, an inert gas such as an argon gas or a helium gas, a nitrogen gas, a carbon dioxide gas, or the like is used. No. These can be used alone or in combination of two or more.
[0025]
Also, the supply rate of the carrier gas is not particularly limited, and is usually 10 to 500 cm ³ / min, preferably, in consideration of the volume of the gas-permeable porous container, the specific gravity of the vaporizable substance, the vaporization (sublimation) rate, and the like. What is necessary is just to select arbitrarily in the range of 50-100 cm < ³ > / min. If the supply rate is too low, the vapor pressure tends to be unstable due to insufficient mixing of the vaporizable substance and the carrier gas, while if it is too high, the vaporizable substance is supplied as a solid without vaporizing There is a tendency.
[0026]
The heating means 24 may be in accordance with the method exemplified above. Further, the heating temperature may be arbitrarily selected in consideration of the thermal conductivity of the gas-permeable porous container and the holding container, the vaporization (sublimation) temperature of the vaporizable substance, and the like.
[0027]
By using the vaporizer, when a source gas containing a certain amount of vaporized material is to be supplied for a long time, the vaporized material is efficiently degraded (including decomposition, sticking, and the like) due to heating, and is efficiently used. Conventional problems such as inability to vaporize can be solved, and the phenomenon that the surface of the vaporizable substance in the container is melted and solidified, and the vaporization of the vaporizable substance located inside is obstructed. I can't. That is, since the partially or entirely altered vaporizable substance cannot be reused, no significant loss is caused.
[0028]
As described above, by using the means including the vaporizer as the raw material introduction means, the raw material components including the gaseous substance involved in the film formation can be used as they are, while maintaining the flow rate of the gas from the gas supply means provided in the vaporizer. It can be introduced by using it.
[0029]
【Example】
Hereinafter, the present invention will be described specifically with reference to examples.
1. Sublimation reference example 1 using vaporizer
An aluminum cylindrical porous container (inner diameter 30 mm, thickness 10 mm, height 45 mm, hole diameter 0.5-1 mm) is placed in a stainless steel container, and dipivaloyl methanate zirconium powder is placed inside the container. 1 g was left still. After sealing the stainless steel container, argon gas was introduced as a carrier gas at a supply rate of 50 cm ³ per minute while the internal pressure of the container was reduced to 3 Torr using a vacuum pump. Electricity was supplied to the heating resistance wire attached to the outer peripheral portion of the container, and the container was heated to 210 ° C. As a result, the weight of the dipivaloyl methanate zirconium powder decreased linearly with time, and the raw material powder was completely vaporized after 20 minutes. Nothing remained in the porous container.
[0030]
Reference Example 2
The procedure was performed in the same manner as in Reference Example 1 except that the raw material powder was dipivaloyl methanate yttrium and the heating temperature was 160 ° C. As a result, the weight of the raw material powder decreased linearly with time, and the raw material powder was completely vaporized after 25 minutes. Nothing remained in the porous container.
[0031]
Reference Example 3
1 g of dipivaloyl methanate zirconium is placed in a zirconium boat (height: 5 mm, width: 5 mm, length: 30 mm, rectangular only opening on top), and placed in a stainless steel tube equipped with a carrier gas inlet and a vaporized substance outlet. And placed in an electric furnace. While the inside of the stainless steel tube was depressurized to 3 Torr by a vacuum pump, argon gas was introduced as a carrier gas at a supply rate of 50 cm ³ per minute. When heated to 210 ° C., the weight of the raw material powder decreased with time and became smaller at 0.15 g after 15 minutes, after which no change in weight was observed. Inside the zirconium boat, a brownish translucent substance was attached to the bottom.
[0032]
Reference example 4
The procedure was performed in the same manner as in Reference Example 3 except that the raw material powder was dipivaloyl methanate yttrium and the heating temperature was 160 ° C. As a result, the rate of decrease of the weight of the raw material powder decreased with time, became constant at 0.20 g after 10 minutes, and thereafter, no change in weight was observed. Inside the zirconium boat, a brownish translucent substance was attached to the bottom.
[0033]
2. Formation of Film Hereinafter, an example in which an yttrium-stabilized zirconia film is formed on a Ni-based superalloy substrate using the film forming apparatus shown in FIG. 1 will be described.
EXAMPLE 1 g of dipivaloyl methanate zirconium and 0.3 g of dipivaloyl methanate yttrium were used as vaporizable substances, and two vaporizers 2 used in Reference Example 1 in the configuration of FIG. At 220 ° C. and 170 ° C., respectively. Each vaporized raw material component was supplied through the delivery pipe 25 by argon gas supplied from a high-pressure argon cylinder as the gas supply means 3. At this point, a mixed gas containing two mixture raw material compounds was obtained. The mixture from the raw material component supply port 4 and the oxygen gas from the separately provided raw material supply means 21 are substantially perpendicular to the substrate 10 made of a disk-shaped Hastelloy-XR alloy having a diameter of 15 mm and a thickness of 2 mm. Simultaneous and continuous introduction at the same concentration. Thereafter, the internal pressure of the film forming chamber 5 was set to 7 Torr by the exhaust device 6. As the laser generator 7 used for heating, a laser light source provided with YAG was used. The output during irradiation is 150W. The laser beam was adjusted so that the irradiation area on the substrate surface had a diameter of about 15 mm. The film formation time (time from the start of laser beam irradiation to the stop of laser beam irradiation) was set to 15 minutes.
[0034]
The substrate was taken out of the film formation chamber, and the formed film was observed with a scanning electron microscope. As a result, it was found that a film in which columnar crystals were oriented perpendicular to the substrate was formed as shown in FIG. The film thickness was 60 μm. When this film was analyzed by an X-ray diffraction method, a peak of yttrium-stabilized zirconia was detected (FIG. 4).
[0035]
In the interior of the film formation chamber after the film was formed, the raw material components reacted on portions other than the substrate surface, and there was no trace of the film formed, and the film could be formed on the substrate with high efficiency.
[0036]
In the above embodiment, the heating is performed by irradiating a laser beam. However, the substrate may be heated by using a known heating means such as a heater. In this case, in order to form a film at the position irradiated with the laser beam, it is necessary that the heating by a heater or the like be performed at a temperature lower than the reaction temperature of the raw material components.
Further, in the above embodiment, the main source gas for forming the film and the oxygen gas were separately introduced in the direction of the substrate, but the present invention is not limited to this. May be.
[Brief description of the drawings]
FIG. 1 is a schematic explanatory view of a film forming apparatus.
FIG. 2 is a schematic explanatory view of a vaporizer.
FIG. 3 is a photograph showing a film obtained in an example.
FIG. 4 is an X-ray diffraction image of a film obtained in an example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1; Film-forming apparatus, 2; Vaporizer, 21; Holding container, 22; Air-permeable porous container, 23; Vaporizable substance, 24; Heating means, 25; Delivery pipe, 3; Component supply port, 5; film formation chamber, 6; cooling device, 7; laser generator, 8; optical device (lens), 9; exhaust device, 10;

Claims (5)

A method of forming a film on the surface of a substrate, wherein a laser beam is irradiated on the substrate surface while introducing a raw material component containing a gaseous substance in the direction of the substrate, and the reaction of the raw material component simultaneously with the heating of the substrate results in a reaction product. A film forming method comprising forming a film. 2. The film forming method according to claim 1, wherein the raw material components are introduced vertically to the substrate. Raw material introducing means, a film forming chamber in which raw material components are introduced from the raw material introducing means, and a substrate is disposed therein, and a laser generator disposed in the film forming chamber and irradiating the substrate with a laser And a film forming apparatus. 4. The film forming apparatus according to claim 3, wherein said raw material introducing means includes a vaporizer. The said vaporization apparatus is provided with a gas-permeable porous container, a heating means for heating the gas-permeable porous container, and a gas supply means for supplying a predetermined gas into the gas-permeable porous container. 5. The film forming apparatus according to item 1.

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