JPH10237634A - Formation of coating - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coating forming method capable of stably forming thin coating with a wide area over a long period with mass-productivity. SOLUTION: In a method in which a solid raw material 16 is irradiated with a pulse-shaped laser beam 29 to execute abrasion, by which the evaporated substance is adhered to a substrate 27 to form coating, the solid raw material 16 is irradiated with the laser beam 29 having >=1J/cm<2> average fluence and cross-sectional shape with >=50 aspect ratio, which is converted from the laser beam having <=0.8J/cm<2> average fluence and >=4cm<2> area.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a film forming method,
In particular, the present invention relates to a method of forming a film on a desired substrate by evaporating a solid material by laser beam irradiation.

[0002]

2. Description of the Related Art At present, vacuum evaporation and sputtering are widely used as a method of evaporating a solid raw material to form a film on a substrate.

However, in the former method, when a compound thin film composed of a plurality of elements having different vapor pressures is formed, there is a problem that the composition of the film deviates from the composition of the raw material.
Further, it is not possible to form a film of a high melting point material such as a metal oxide, nitride, and carbide.

On the other hand, in the latter method, a thin film of a high melting point substance can be obtained relatively easily. However, the latter method
Generally, it takes at least one hour to form a thin film of 1 μm with a low film forming speed. 0.001 Torr
Since the film is formed in an Ar atmosphere of r or more, scattering by Ar atoms occurs, and the directivity of the evaporated particles is easily lost. This causes so-called wraparound, which causes the particles to adhere to the shaded portion with respect to the adhered surface, which should not originally adhere to the substrate.

[0005] For these reasons, the laser deposition method has recently attracted attention. In this method, a solid material such as a target is irradiated with a short-wavelength ultraviolet laser beam and evaporated to form a film. Normally, even when a substance having a strong binding force is used as the target, when light having a wavelength of 300 nm or less is irradiated, electrons involved in the bond are excited, and the bond between atoms is cut. Therefore, even high melting point substances can be evaporated. Further, since the evaporated particles such as atoms have high kinetic energy and directivity, 1
Even if a film is formed by introducing a reaction gas at a high pressure of about rr,
The directivity and the like are hardly lost. Therefore, metal oxides, nitrides, carbides, and the like can be formed on the substrate using the metal raw material and the reaction gas. For example,
It is possible to form a thin film of a substance that is not found in nature such as TiN and TiC and is difficult to obtain as a solid material.

[0006] However, the laser vapor deposition method has a problem that the vapor deposition area is small. That is, in order to irradiate the target with a laser beam and evaporate the target, an irradiation energy density higher than a certain threshold, so-called “fluence” is required. For this reason, since the laser is condensed by a lens or the like and irradiates the target, the region to be evaporated must be narrowed. Therefore, it becomes difficult to form a thin film having a large area.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide a film forming method capable of stably and mass-producing a thin film having a large area over a long period of time.

Another object of the present invention is to provide a film forming method capable of forming a thin film having a uniform film thickness over a wide area and in which a second component such as an impurity is uniformly dispersed. is there.

[0009]

According to the present invention, there is provided a method for forming a film by irradiating a solid material with a pulsed laser beam to perform ablation, and attaching an evaporated substance to a substrate to form a film. laser converted has 0.8 J / cm ² or less of the average fluence and 4cm has ^two or more average area from a laser beam with a 1 J / cm ² or more fluence, and the cross-sectional shape with more than 50 aspect ratio A beam is applied to the solid raw material.

Another film forming method according to the present invention is directed to a method of irradiating a solid material with a pulsed laser beam to perform ablation, and attaching a material evaporated by the method to a substrate to form a film. And a step of arranging a mask having one or more openings between the substrate and the substrate, and then simultaneously or sequentially evaporating the solid raw material from a plurality of locations.

In another film forming method according to the present invention, a ratio (L) of a width (W) to a length (L) on an irradiation surface of the substrate is provided.
/ W) is permitted to use a laser beam having a band-shaped pattern of 10 times or more.

Still another method of forming a film according to the present invention is a method of irradiating a solid material with a pulsed laser beam to perform ablation, and attaching a substance evaporated by the method to a substrate to form a film. While rotating at a desired speed, a plurality of solid raw materials arranged below the substrate are irradiated simultaneously or sequentially with laser beams having different fluences.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a film forming method according to the present invention will be described with reference to the drawings.

FIG. 1 is a schematic diagram showing a film forming apparatus used in the film forming method according to the present invention.

A cylindrical vacuum vessel 5 having a top plate 3 and a bottom plate 4 at the top and bottom is hermetically fixed to the support plate 2 of the gantry 1. The first exhaust pipe 7 to which the main valve 6 is connected is
It is attached to the left side wall of the vacuum vessel 5. A turbo pump 8 and a rotary pump 9 are sequentially connected to the main valve 6. The laser light introduction tube 10 is inclinedly connected to the right side wall of the vacuum vessel 5, and the transmission window 11 is attached to a tip of the introduction tube 10. A bottomed cylindrical box 13 having an upper plate 12 is hung on the top plate 3 of the vacuum vessel 5 so that the bottom extends into the vacuum vessel 5. The halogen lamp 14 is disposed near the bottom of the box 13 and the lamp 1
The leads at the four ends are connected to a pair of terminals 15a and 15b attached to the upper plate 12 of the box 13, respectively. A rotary pump (not shown) is connected to the upper plate 12 of the box 13 through a second exhaust pipe (not shown), and by increasing the inside of the box 13 to a predetermined degree of vacuum, the radiant energy from the halogen lamp 14 is increased. It is trying to make it.

Solid material, for example, a cylindrical target 16
Is rotatably arranged near the bottom in the vacuum vessel 5 so that its axis is located in the horizontal direction. A disk-shaped shutter 17 is supported and fixed on a rotating shaft 18 that extends through the support plate 2 and the bottom plate 4 into the vacuum vessel 5 so as to be positioned above the target 16. .
The rotation shaft 18 is rotated by a motor (not shown) attached to the lower surface of the support plate 2. Substrate holder 19
Is arranged in the vacuum vessel 5 between the shutter 17 and the box 13.

The excimer laser oscillator 20 is arranged outside the vacuum vessel 5. In an optical path of the laser light emitted from the laser oscillator 20 to the transmission window 11, a mirror 21 and a condenser lens 22 made of, for example, a cylindrical lens are sequentially arranged from the laser oscillator 20 side. The excimer laser oscillator 20 applies a voltage of several tens of kilovolts between electrodes disposed therein, and applies a mixed gas of Kr, F ₂ and Ne at several atmospheric pressures, or A
Oscillation is performed based on plasma formed by discharging in a mixed gas of r, F ₂ and Ne. However, when the gas pressure increases, the discharge becomes difficult to occur. Therefore, a predischarge electrode is provided, and the main discharge is induced by using the electrons jumped out by the discharge between them as a trigger. When the beam area is to be increased, the height H and the distance L between the pair of main electrodes 23 facing each other are increased as shown in FIG. Or an auxiliary ionizing electrode 24 is disposed near the center of the discharge space of the pair of main electrodes 23 as shown in FIG. 3, and X is applied to the main discharge space existing between these main electrodes 23.
Discharge is performed between the preliminary ionization electrode 24 and the pair of main electrodes 23 having different potentials while the excitation electromagnetic wave such as a line or a laser beam is injected. In the latter method, since the preliminary ionization electrode 24 is arranged in the main discharge space, the fluence near the center of the oscillated laser beam is small, and the uniformity may be reduced. In this case, as shown in FIG. 4, it is desirable that the beam be spread by a concave lens 25 having two curved surfaces and then condensed by a cylindrical convex lens 26. The former method requires a large-scale apparatus, but provides a beam with good uniformity.

Next, a film forming method according to the present invention using the film forming apparatus shown in FIGS. 1 and 2 will be described.

First, a desired substrate 27 is supported and fixed in a concave portion of the substrate holder 19 arranged in the vacuum vessel 5. By driving the turbo pump 8 and the rotary pump 9, the gas in the vacuum vessel 5 is exhausted through the main valve 6 and the first exhaust pipe 7, and the inside of the vacuum vessel 5 is brought to a desired degree of vacuum. Further, a rotary pump (not shown) is driven to exhaust the gas in the box 13 through a second exhaust pipe (not shown), and the inside of the box 13 is evacuated to the same degree of vacuum as that of the vacuum vessel 5. , 15b to generate heat by energizing the halogen lamp 14, thereby heating the substrate 27 disposed below the halogen lamp 14 to a desired temperature. By driving a motor (not shown),
By rotating the shutter 8, the shutter 17 supported by the rotation shaft 18 is positioned directly above the cylindrical target 16.

After the preparation for the film formation is completed, the laser oscillator 20 in which the height H and the distance L between the pair of main electrodes 23 facing each other are increased as shown in FIG. A laser beam 28 having an average fluence of 0.8 J / cm ² or less and an area of 4 cm ² or more is oscillated. The laser beam 28 is
The laser beam 29 having an average fluence of 1 J / cm ² or more and having a wide area with an aspect ratio of 50 or more is condensed and modulated by the condenser lens 22 at a predetermined focal length. Transmission window 11 of the vacuum vessel 5
Is irradiated on the target 16 having a cylindrical shape.

In the irradiation of the cylindrical target 16 with the laser beam 29 having a wide area having an aspect ratio of 50 or more, the target component is evaporated from the target 16 as shown in FIG. 30 is obtained. For example, the length (length along the axial direction of the target 16) is 10 due to the combination of the convex lens and the concave lens constituting the condenser lens 22 composed of the Fresnel lens.
When the target 16 is irradiated with a laser beam 29 having a width of 0 mm and a width of 1 mm perpendicular to the length direction, a vapor deposition area having a length of 200 mm and a width of 20 mm is obtained at a position 5 cm away from the target 16. When the evaporation state is stabilized, the rotating shaft 18 is rotated to open the shutter 17 supported by the rotating shaft 18. When the shutter 17 is opened, the evaporating substance from the target 16 is held by the holder 19 and adheres to the lower surface of the substrate 27 heated by the halogen lamp 15 to form a film.

As the target 16, for example, Y-
Ba-Cu, Bi-Sr-Ca-Cu, Tl-Ba
-Ca-Cu system, Hg-Ba-Ca-Cu system, Nd-B
a-Cu based oxide superconductor forming target; B
aTiO _3, PbTiO _3, LiNbO dielectric target for forming such _3; wire forming targets such WSiN _X; GaAs, it is possible to use a compound semiconductor forming the target, etc., etc. GaAlP.

The laser beam 28 emitted from the laser oscillator 20 must have a fluence of 0.8 J / cm ² or less. When a laser beam having a fluence exceeding 0.8 J / cm ² is used, the vacuum vessel 5
If the mirror 21 and the transmission window 11
May be destroyed. Therefore, the fluence of the laser beam oscillated from the laser oscillator 20 is 0.8 J / cm ² or less, more preferably 0.4 J / cm 2.
² or less, more preferably 0.2 J / cm ² or less.

The laser beam 28 oscillated from the laser oscillator 20 must have a beam area of at least 4 cm ² or more, more preferably 6 cm ² or more, and further preferably 10 cm ² or more. This is for the following reason.

That is, as described above, when forming a film over a large area on the substrate, the pattern size of the laser beam 29 applied to the target 16 may be increased in the length direction. However, in consideration of evaporation due to irradiation on the target 16, it is necessary that the laser beam 29 has at least an average fluence of 1 J / cm ² or more. Therefore, in the laser beam 29, when the axial length of the target 16 is doubled, the width needs to be halved. In that case, since the width of the deposition area is also reduced to half, the film forming speed is reduced.

To irradiate a laser beam 29 having an average fluence of 1 J / cm ² ,
8 needs to have an area at least 1.25 times or more the irradiation area. However, this is the case when the fluence of the oscillated laser beam 28 is 0.8 J / cm ² and the loss in the mirror, the lens, and the transmission window is zero. Actually, since the fluence is reduced to about 50% in the optical path of the laser beam 28, at least 2.5 times the area is required. It is desirable to lower the oscillation power by forming a beam.

From the above, the laser oscillator 2
At least 4 as the laser beam 28 oscillated from 0
By designing so as to have a beam area of not less than cm ^2, it becomes possible to stably irradiate the target 16 with the laser beam 29 having a wide area over a long period of time to form a film.

Generally, the cross-sectional area of an excimer laser is as small as about 2 cm ² . When a large area is to be processed by laser annealing or the like, the laser output is increased and the engineering system is devised to increase the cross-sectional area. However, when applied to vapor deposition for film formation, higher energy is required than annealing.
The life of the lens and the transmission window is shortened.

Therefore, since the fluence can be lowered as the area becomes larger, the laser beam from the laser oscillator 20 having a low fluence and a large area can be obtained by the film forming method of the present invention.
Oscillates. Such a low-fluence, large-area laser beam 28 can be realized by using the oscillator having the structure shown in FIG. 2 or FIG.

The laser beam 29 applied to the target 16 has an average fluence of 1 J / cm ² or more.
It is necessary to have a wide area with an aspect ratio of 50 or more, more preferably 100 or more. If the aspect ratio is less than 50, it is difficult to form the vapor deposition area 30 having a sufficiently large area from the target 16.

When forming the film on the substrate 27, if the length and width of the substrate held by the holder 19 are smaller than the length and width of the deposition area 30, respectively, the substrate 27 is stopped by the holder 19. It is possible to form a film. On the other hand, when holding a long substrate or a large number of substrates in the holder, the substrate 27 is moved so as not to protrude from the deposition area 30. The movement may be a one-way movement or a reciprocating movement.

According to the present invention described above, a low-fluence, large-area laser beam oscillated from a laser oscillator is shaped into a pattern having a large aspect ratio and irradiated onto a target, whereby a thin film is efficiently formed on the substrate surface. In addition, a film can be formed stably over a long period of time.

In the film forming method of the present invention, a target is irradiated with a laser beam to evaporate the target.

Furthermore, since the evaporation mechanism is not thermal melting, even when a thin film of a compound composed of a plurality of elements having different vapor pressures is formed, a thin film having the same composition as that of the solid material (target) is formed. Obtained and excellent in composition controllability. In addition, since it can be evaporated with high kinetic energy even in a high pressure reaction gas atmosphere, a high quality thin film can be formed. Here, a good quality thin film is a film that is dense and extremely close to the stoichiometric composition.

In irradiating the target with the laser beam, the following mode can be adopted in addition to the above-described configuration shown in FIG.

(1) As shown in FIG.
To the target 16 so that the length of the laser beam 29 is longer than the length of the target 16 (length along the axial direction). By irradiating the laser beam 29 as described above, both ends of the target 16 can be used as an evaporating section, which is effective for long-time film formation.

However, the laser beam which is not irradiated on the target 16 hits the inner wall and the jig of the vacuum vessel 5 and may evaporate the constituent elements. In such a case, the laser beam 29
The laser beam 19 in the direction in which
By forming a portion within a certain distance L 'from the substrate 27 on the emission side with the target material, the introduction of impurities into the formed thin film can be prevented. The constant distance is
It is desirable that the focal length f be at least 0.2 to 2 times the focal length f of the lens used for focusing.

(2) As shown in FIG. 7, laser beams 28 ₁ and 28 _{2 are} output from _two laser oscillators 20 ₁ and 20 _2.
At the same time, these laser beams 28 ₁ , 28 ₂ are transmitted through the prisms 31 ₁ , 31 ₂ and the main prism 32 and reflected on the mirror 21 to form a continuous large area pattern. , Through the transmission window 11 into the vacuum vessel 5. According to such a method, it becomes possible to irradiate the target with a laser beam having a larger area.

In shaping the large-area laser beam, the respective laser beams 28 ₁ and 28 ₂ may be overlapped.

(3) As shown in FIG. 8, a concave lens 33 and a convex lens 34 are arranged in a vacuum vessel 5, and condensed by a condenser lens 22 disposed outside the vessel 5, and further pass through a transmission window 11. The laser beam 29 is transmitted to the concave lens 33.
Then, the laser beam 29 ′ is made to have a large area by passing through the convex lens 34 and the laser beam 29 ′ is irradiated on the target 16. By arranging the concave lens 33 and the convex lens 34 in the vacuum vessel 5 as described above, the manufacturing cost is increased, and the aspect ratio is large.
It is possible to irradiate the target 16 in the container 5 with the laser beam 29 ′ having a large area without disposing the laser beam 29 ′.

Next, another film forming method according to the present invention will be described in detail with reference to the drawings.

FIG. 9 is a schematic view showing a film forming apparatus used in another film forming method according to the present invention, FIG. 10 is a perspective view showing a main part of the film forming apparatus shown in FIG. 9, and FIG. It is the top view seen from.

The support plate 52 of the gantry 51 has a top plate 5
A cylindrical vacuum vessel 55 having a bottom plate 3 and a bottom plate 54 is airtightly fixed. The first connected main valve 56
The exhaust pipe 57 is attached to the left side wall of the vacuum vessel 55. The main valve 56 has a turbo pump 5
8 and the rotary pump 59 are sequentially connected. The laser light introducing tube 60 is inclinedly connected to the right side wall of the vacuum vessel 5, and the transmission window 61 is attached to the tip of the introducing tube 60. A bottomed cylindrical box 63 having an upper plate 62 is hung on the top plate 53 of the vacuum vessel 55 so that the bottom portion extends into the vacuum vessel 5. The halogen lamp 64 is disposed near the bottom of the box 63, and leads at both ends of the lamp 64 are connected to a pair of terminals 65 attached to the upper plate 62 of the box 63.
a, 65b. A rotary pump (not shown) is connected to the upper plate 62 of the box 63 through a second exhaust pipe (not shown).
By setting the inside of the inside to a predetermined degree of vacuum, the radiant energy from the halogen lamp 64 is increased.

A plurality of, for example, three disk-shaped targets 6
6, a first rotating shaft 67 that extends through the support plate 52 and the bottom plate 54 near the bottom of the vacuum vessel 55 and extends into the vacuum vessel 55 near the bottom of the vacuum vessel 55, as shown in FIGS. It is rotatably supported and fixed. The disk-shaped targets 66 are arranged in a radial direction of a disk-shaped mask described later. The disk-shaped shutter 68 is provided on the second rotary shaft 69 extending through the support plate 52 and the bottom plate 54 and into the vacuum vessel 55, so that each of the targets 66
Is supported and fixed so as to be located above. The first and second rotating shafts 67 and 69 are rotated by motors (not shown) mounted on the lower surface of the support plate 52, respectively.

For example, a mask material 71 having a fan-shaped opening 70 is arranged between the plurality of targets 66 and a substrate on which a film is to be formed, as shown in FIGS. The fan-shaped opening 70 is formed in the mask material 71 so as to extend in the direction in which the plurality of targets 66 are arranged. In addition, reference numeral 72 shown by a dashed line in FIG. 11 indicates a deposition area of particles such as atoms evaporated from each of the targets 66.

The substrate holder 74 supported and suspended by the rotating shaft 73 is rotatably disposed in the vacuum vessel 5 so as to be located above the mask shutter 68.

The laser oscillator 75 is disposed outside the vacuum vessel 55. In the optical path of the laser beam oscillated from the laser oscillator 75 to the transmission window 61,
A mirror 76 and a condenser lens 77 made of, for example, a cylindrical lens are sequentially arranged from the laser oscillator 75 side. The polygon mirror 78 is arranged near the bottom in the container 55 as shown in FIG. The polygon mirror 78 reflects the laser beam transmitted through the transmission window 61 to irradiate the plurality of targets 66.

Next, another film forming method according to the present invention will be described using the film forming apparatus shown in FIGS.

First, a desired substrate 79 is supported and fixed in a concave portion of the substrate holder 74 arranged in the vacuum vessel 55, and is rotated at a desired speed by driving the rotating shaft 73. The turbo pump 58 and the rotary pump 59 are driven to supply the gas in the vacuum vessel 55 to the main valve 56 and the first valve.
The air is exhausted through the exhaust pipe 57 to make the inside of the vacuum vessel 55 a desired degree of vacuum. Further, a gas in the box 63 is exhausted through a second exhaust pipe (not shown) by driving a rotary pump (not shown), and the inside of the box 63 is evacuated to the same degree of vacuum as the vacuum vessel 55. , 65b
The substrate 79 disposed below the halogen lamp 64 is heated to a desired temperature by supplying electricity to the halogen lamp 64 to generate heat. By driving a motor (not shown) to rotate the second rotation shaft 69, the shutter 68 supported by the rotation shaft 69 is moved to the mask material 7.
Position directly above 1.

After the preparation for such a film formation is completed, the laser oscillator 75 is operated to operate the laser beam 80.
Is oscillated. The laser beam 80 is reflected by the mirror 76 and is condensed by the condenser lens 77 at a predetermined focal length.
The focused laser beam 80 is introduced into the container 55 through the transmission window 61 of the vacuum container 55. The introduced laser beam 80 is reflected by a polygon mirror 78 rotating at a desired speed as shown in FIG. 10, and each of the three disk-shaped targets 66 rotated at a desired speed by a first rotating shaft 67. Is irradiated.

The laser beam 78 is applied to each of the targets 66.
Irradiates the target components. When the evaporation of the target component from each target 66 is stabilized, the second motor (not shown) is driven to rotate the rotating shaft 69, thereby opening the shutter 68 supported by the rotating shaft 69. . At this time, the mask material 71 having a fan-shaped opening 70 formed in the direction in which the three targets 66 are arranged is placed on each of the targets 6.
6 and the substrate 79, the particles evaporated from each of the targets 66 pass through the fan-shaped openings 7.
The thin film having a uniform thickness is formed on the lower surface of the substrate 79 because the thin film is adhered to the rotating substrate 79 above the mask material 71 through 0.

That is, when the particles are evaporated from the plurality of, for example, three targets 66 by the same amount and are directly attached to the substrate, the film thickness becomes thicker toward the center of the substrate. As described above, by disposing the mask material 71 having the fan-shaped opening 70 between each of the targets 66 and the substrate 79, when evaporating particles from each of the targets 66 pass through the opening 70, Substrate 79
Since the amount of evaporated particles from the target 66 located at the center of rotation of the rotating substrate 79 is reduced, the evaporated particles are uniformly attached to the rotating substrate 79. As a result, a thin film having a uniform thickness is formed on the lower surface of the substrate 79.

As the target 66, for example, Y-
Ba-Cu, Bi-Sr-Ca-Cu, Tl-Ba
-Ca-Cu system, Hg-Ba-Ca-Cu system, Nd-B
a-Cu based oxide superconductor forming target; B
aTiO _3, PbTiO _3, LiNbO dielectric target for forming such _3; wire forming targets such WSiN _X; GaAs, it is possible to use a compound semiconductor forming the target, etc., etc. GaAlP.

The mask material 71 is used for the target 66.
It is desirable to dispose it between the substrate 79 and the substrate 79. However, the mask material 71 is
If it is too close to the opening, it becomes difficult for active oxygen to be supplied to the lower surface of the substrate 79 covered by the area other than the opening 70, so that it is desirable that the distance is 1 mm or more, preferably 1 cm or more.

The shape of the opening 70 of the mask material 71 is as follows.
If the radius of the sector shown in FIG. 11 is R, the radius of the uniform deposition area from each target 66 is r, and the central angle is θ, R
It is preferable to determine the central angle θ such that θ ≦ 2r.

In the opening 70 of the mask material 71, a fan-shaped linear portion may be curved. In this case, it is desirable to change the fan shape according to the degree of overlap of the deposition areas 72 of the particles evaporated from the adjacent targets 66. For example, when the degree of overlap between the deposition areas 72 from the adjacent targets 66 is large, an opening 70 having a constricted portion corresponding to the overlapped portion is formed in the mask material 71 as shown in FIG. . On the other hand, the adjacent target 6
When the degree of overlap of the vapor deposition areas 72 from 6 is small, or when there is no overlap between the vapor deposition areas 72, a bulging portion is formed at a position corresponding to the overlapping portion (or the adjacent portion) as shown in FIG. The opening 70 is formed in the mask material 71.

Also in the case of forming a film while reciprocating the substrate linearly, a mask material having openings provided between a plurality of targets and the substrate is disposed. It is desirable that the shape of the opening of the mask material be changed according to the degree of overlap of the evaporation areas of the evaporated particles constituted by atoms and the like from adjacent targets. For example, when the degree of overlap between the deposition areas 81 from adjacent targets is large, an opening 82 having a constricted portion corresponding to the overlapping portion is formed in the mask material 71 as shown in FIG. On the other hand, when the degree of overlap of the deposition area 81 from the adjacent target is small or distant, the deposition area 81 has a swollen portion at a position corresponding to the overlap portion (or the adjacent portion) as shown in FIG. An opening 82 is formed in the mask material 71.

The method of evaporating a target from a plurality of locations is not limited to the case where a plurality of targets are used as described above. For example, a plurality of locations of a large target may be irradiated with a laser beam. In this case, the shape of the opening of the mask material is set according to the distance between a plurality of irradiation positions on the large target.

The method of evaporating a target from a plurality of locations is not limited to the case where a polygon mirror is used as described above. For example, a plurality of targets or a large target may be irradiated with a laser beam using a plurality of laser oscillators. When one laser oscillator is used, a plurality of laser beams may be formed from a laser beam oscillated from the oscillator using a beam splitter. However, the polygon mirror described above is suitable for increasing the laser beam irradiation repetition frequency.

When a large target is used, the laser beam is focused on the target in a linear manner,
Alternatively, it is preferable to scan with a laser beam. However, when the target rotates in a circular shape, it is desirable to focus the laser beam on a region not including the rotation center of the target. When the laser beam is applied to the vicinity of the center of rotation of the target, the laser beam is constantly applied to the vicinity of the center of rotation. Therefore, only the target in this portion is dug deeply and defocus occurs. As a result, there is a possibility that the film thickness becomes non-uniform due to a composition deviation or a change in the shape of the plume. Therefore, when irradiating the target with the laser beam, it is preferable that the laser beam is condensed on the target 66 in a region 83 extending in the radial direction excluding the vicinity of the rotation center as shown in FIG. However, it is desirable that the size of the target be as large as possible in order to minimize the difference between the moving speeds of the part near and far from the center of rotation of the target. For example, it is desirable to use a target having a diameter at least twice or more, more preferably three times or more, the length of the irradiation area of the focused laser beam.

Further, as shown in FIG. 14B, the laser beam may be focused on the target 66 in a region 84 parallel to the diameter crossing the center of rotation of the target 66. In this case, since the moving speed of the laser beam irradiation area is substantially the same regardless of the position in the laser beam irradiation pattern, it is possible to avoid the target from being dug locally during the laser beam irradiation. In addition, since the area of the target can be made relatively small, it can be used as long as it satisfies the condition of a target having a diameter of at least 1.5 times the length of the focused laser beam on the irradiation surface. .

Further, in order to form a thin film having a large area and a uniform thickness on a substrate, it is preferable that a laser beam pattern formed by irradiating a target has a long shape of the laser beam. . For example, the length (L) of the linear pattern of the laser beam is preferably at least 以上 or more of the radius of the substrate. In the laser beam pattern, the width (W) of the linear pattern of the laser beam is 5 mm or less, more preferably 1 m.
m or less. This is because the laser beam is obliquely incident on the target, and the defocused portion is likely to occur in the pattern before and after along the laser beam incident direction. Since the fluence is low in the part where the focus is shifted, the composition of the formed thin film is shifted due to the fact that the element having a high vapor pressure is easily evaporated. By setting the width (W) of the pattern to 5 mm or less as described above, it is possible to prevent a portion having a low fluence due to the defocus from occurring in the irradiation pattern. Therefore, in the irradiation pattern on the target, the ratio (L / L) of the length (L) to the width (W) is used.
W) is preferably at least 10 times, more preferably at least 30 times.

To focus the laser beam linearly,
For example, as shown in FIGS.
A method of condensing a lens system combining a concave lens 85 and a convex lens 86 having a cylindrical surface with 0 is adopted. When focusing a laser beam using such a lens system,
The length (L) of the laser beam irradiated on the target is determined by the focal length (curvature) of the concave lens 85, and the width (W) is determined by the focal length of the convex lens 86. Especially,
In order to increase the fluence of the laser beam, it is preferable to narrow the width (W). Therefore, 300m
m or less, preferably 100 mm or less focal length (curvature)
Condensed laser beam with concave lens 85 having width (W)
Is preferably 1 mm or less.

According to another film forming method of the present invention described above, after a mask material having an opening is disposed between a target and a substrate, the target is simultaneously or sequentially evaporated from a plurality of locations corresponding to the opening. By doing so, a thin film having a uniform thickness can be formed on a substrate having a large area.

That is, when the target is evaporated from one place, as shown in FIG. 23, the thickness distribution occurs in the thin film formed on the substrate, and the uniform region becomes narrow. On the other hand, when the targets are arranged at intervals of 30 mm and evaporated from these targets, the uniformity of the thickness of the thin film formed on the substrate is improved as shown in FIG.
However, when the target is evaporated from a plurality of locations and the substrate is rotated in order to form a film on the entire surface of the plate-like substrate, when the amount of evaporation from each target is the same, the film is formed closer to the center of the substrate. The deposited thin film becomes thicker.

In view of the above, according to the present invention, by interposing a mask material having an opening (for example, a fan-shaped opening) between the target and the substrate, particles evaporated from a plurality of targets can be removed from the opening. When passing through
The amount of particles that pass toward the center of rotation of the substrate can be suppressed. As a result, a thin film having a uniform thickness can be formed on a substrate having a large area.

Next, still another film forming method according to the present invention will be described with reference to FIGS.

As shown in FIG. 17, a vacuum vessel (not shown)
The laser beam 92 condensed is reflected by a polygon mirror 93 while rotating a substrate 91 held by a holder (not shown) in the inside, so that an energy density (fluence) is obtained.
Laser beams 94 ₁ and 94 ₂ of different compositions
The substrate 91 is irradiated by irradiating _two targets 95 ₁ and 95 _2.
On the lower surface of the first and second targets 95 having different compositions.
_1, forming a thin film made of a 95 _second component. The targets 95 ₁ and 95 ₂ are arranged symmetrically with respect to the center of rotation below the substrate 91, for example.

The first target 95 ₁ is, for example, YB
Made from CO.

The second target 95 ₂ is, for example, C
u, Y, Y ₂ BaCuO ₅ , La, Sr, Ag, Au,
It is made from elements that do not react with YBCO, such as Ce, Ce ₂ O ₃ , MgO, SrTiO ₃ , and CeO ₂ , and compounds thereof.

The first and second targets 95 ₁ , 95
The evaporation timing between the _two is preferably as short as possible. For example, the time from evaporating the first target 95 ₁ made of YBCO to evaporating the next second target 95 ₂ is 1 second or less, more preferably 0.1 second or less.
It is preferable that the time be 1 second or less. However, the substrate 91
Also needs to be changed according to the repetition period of the laser beam. That is, it is preferable that the substrate 91 moves (crosses) between the deposition areas of the first and second targets 95 ₁ and 95 ₂ within the laser beam oscillation interval. When the substrate 91 is rotated, when the rotation speed (rpm) is R and the repetition frequency of the laser beam is f, the rotation speed of the substrate 91 and the laser beam from the laser oscillator are set so that R = 30 × f. It is preferable to set the oscillation frequency.

The irradiation position of the laser beam is fixed,
Although it is possible to rotate the target, it is not practical because the target needs to be rotated in a short time.

The laser beams 9 having different fluences
4 _1, the 94 ₂ is reflected from the polygon mirror 93, the following method is employed. That is, the polygon mirror for excimer laser is composed of a dielectric multilayer film,
Since the number of layers is changed according to the angle of incidence, the range of the angle of incidence for total reflection is limited. Utilizing this property, for example, a first target made of a material having a low vapor pressure is set to be totally reflected at an incident angle when a laser beam is irradiated, and a second target made of a material having a higher vapor pressure than the first target is set. The incident angle when irradiating the target with the laser beam is slightly shifted from the range of total reflection. For example, a 45 ° incident polygon mirror reflects almost completely within a range of 30 ° to 60 °, but if it deviates from that range, the reflectance decreases. For this reason, if the incident angle when irradiating the first target with the laser beam is set to around 60 ° or 30 °, the fluence of the laser beam irradiating the second target becomes weak. Which angle is determined by the target and the incident angle of the laser beam.

Specifically, as shown in FIG. 17, the laser beam 92 is incident on the polygon mirror 93 rotating counterclockwise, and the laser beam
4 ₁ irradiated initially to the first target 95 ₁ on the right side, then the second case of irradiating the target 95 ₂ laser beam 94 ₂ reflected on the left side, near 60 ° angle of incidence of the laser beam 92 To On the other hand, as shown in FIG. 18, a laser beam 92 is incident on a polygon mirror 93 which rotates in a counterclockwise direction, and the laser beam
4 ₁ irradiated initially to the first target 95 ₁ on the left, when the next irradiating a laser beam 94 ₂ reflected on the second target 95 ₂ on the right, near the 30 ° angle of incidence of the laser beam 92 To When irradiating the left target first and then irradiating the right target, the rotation direction of the mirror is clockwise, and the incident angle at the time of total reflection is 30.
Degree near. Distribution of different laser beams 94 _1, 94 ₂ of the power of the fluence, the laser beam 9
2 can be determined by adjusting the angle of incidence.

When a laser beam is reflected by the polygon mirror, a method may be employed in which the laser beam is dropped by a filter before being focused by a lens. In this case, since the two laser beams need to be separated to some extent, the distance from the polygon mirror to the lens becomes long.

The laser beams 9 having different fluences
4 ₁ , 94 ₂ power distribution depends on the laser beam 92
Can be determined by adjusting the incident angle. For example, the first target 95 ₁ YBCO, when made with relatively evaporable metal second target 95 _2, 40 to 90 of the second fluence to the target 95 ₂ fluence to the first target 95 ₁ %, More preferably 60 to 90%. When the first target 95 ₁ is made of YBCO and the second target 95 ₂ is made of an oxide that is relatively difficult to evaporate, the second target 9 1
5 fluence to ₂ 60% to 95% of the fluence of the first target 95 _1, more preferably 70% to 95%
Is desirable.

As a method of irradiating the first and second targets with the laser beams having different fluences, in addition to the above-described method using the polygon mirror, a beam splitter may be used so that the fluences of the laser beams become uneven. May be adopted.

The number of targets is not limited to two, and three or more targets may be arranged below the substrate.

According to the present invention described above, lasers having different energy densities (fluence) are simultaneously or sequentially applied to a plurality of solid raw materials (targets) disposed below the substrate while rotating the substrate at a desired speed. By irradiation, not only can a uniform thin film be formed on a large-area substrate, but also a thin film in which impurities are uniformly dispersed can be formed. For example, one target is YBCO
If another target is made of impurities other than YBCO, a thin film in which a hetero phase serving as a pinning center of magnetic flux is finely dispersed in the YBCO superconducting film can be formed on the substrate.

That is, conventionally, attempts have been made to introduce a pinning center by depositing a different phase in a thin film while shifting the composition from the stoichiometric composition. However, since the film formation rate is low, the excess elements or foreign phases are not finely dispersed but aggregate and precipitate on the grain boundaries and the surface of the thin film. As a result, it could not function as a pinning center.

On the other hand, the laser vapor deposition method used in the film forming method of the present invention can increase the vapor deposition rate by 10 times or more as compared with other film forming methods, and supplies the particles evaporated from the target to the substrate surface. Is performed in a short time of several tens nanoseconds to several microseconds. For this reason, during film formation, excessive elements and foreign phases are not migrated over a long distance and do not aggregate.

Accordingly, by simultaneously or sequentially irradiating a plurality of targets disposed below the substrate with laser beams having different fluences while rotating the substrate at a desired speed as in the present invention, one of the targets is rotated. Impurity components evaporated from one or more other targets are uniformly dispersed without aggregation in the evaporated main component, and for example, a thin film in which a heterogeneous phase serving as a pinning center of a magnetic flux is finely dispersed in a YBCO superconducting film is formed. It can be formed on a substrate.

Next, a method using a mask material in still another film forming method according to the present invention will be described.

As shown in FIG. 17, the condensed laser beam 92 is reflected by, for example, a polygon mirror 93 while the substrate 91 is being rotated, so that the laser beams 94 ₁ and 94 ₂ having different fluences are converted into _two beams having different compositions. The _first and _second targets 95 ₁ , 95 ₂ having different compositions are irradiated on the lower surface of the substrate 91 by irradiating the two targets 95 ₁ , 95 2.
When a thin film composed of the _two components is formed, FIG.
Wherein as shown in 0 first at positions corresponding to each target, a second opening 96 _1, 96 ₂ disc-shaped mask material 97 formed with placed between the target and the substrate. Such an arrangement of the mask material 97 limits the range of vapor deposition on the substrate. Each of the targets is symmetrically arranged below the substrate with respect to its center of rotation. Note that reference numerals 98 ₁ and 98 ₂ indicated by dashed lines in FIG. 19 or FIG.
Reference numeral 9 denotes an annular thin film having a multilayer structure formed on a disc-shaped substrate (not shown) disposed above the mask material 97.

The openings 96 ₁ , 96 of the mask material 97
_{In FIG. 2} , a pair of opposing sides is the mask material 97.
It is preferable that the other side of the mask member 97 be formed so as to intersect at the center of the mask member 97 when the other side extends. Mask material 97 having _first and _second openings 96 ₁ and 96 ₂ having such a shape.
Is used, it is possible to form the annular thin film 99 having a uniform thickness on the substrate thereabove.

The openings 96 ₁ , 96 of the mask material 97
_{In 2} , the width in the direction orthogonal to the direction of rotation of the substrate above it is the diameter (r1) of the annular thin film formed on the substrate.
). The width of each of the openings 96 ₁ , 96 ₂ is:
They may be the same and different. However, when the first target facing the first opening 96 ₁ among the two targets is made of a superconducting material such as YBCO, and the second target facing the second opening 96 ₂ is made of an insulating material. , it is preferable that the second width of the opening 96 ₂ greater than the first width of the opening 96 _1. By using the mask material 97 having the first and second openings 96 ₁ and 96 ₂ having such a shape, the insulating material having a width wider than those of the superconducting layers is formed between the superconducting layers formed on the substrate thereabove. Since a layer can be formed, a short circuit between the superconducting layers can be avoided. In particular, the second width of the opening 96 ₂ is more than 1.1 times of the first opening 96 ₁ of width, more preferably it is desirable to be at least 1.5 times.

The openings 96 ₁ , 96 of the mask material 97
_{In 2} , the rotational length of the substrate above it is related to the amount of particles deposited from the target on the substrate. Further, the rotation speed of the substrate also affects the amount of particles deposited from the target on the substrate. In other words, the longer the length of each opening 96 _1, 96 _2, the adhesion amount from the target to the substrate of the evaporated particles (deposition rate) is increased.

[0088] In the mask material 97, the radius of curvature of the outer periphery of the annular thin 99 to be formed on the substrate R, the annular r ₁ the width of the thin film 99, deposition area 98 _1, 98 ₂ of radius r ₂
Then, the opening angle θ of each of the openings 96 ₁ , 96 ₂ is determined by r ₁ , r ₂ , the positional relationship between the substrate and the target, and the rotation speed of the substrate. The openings 96 ₁ , 96 ₂
To uniformly fit in the deposition areas 98 ₁ and 98 ₂ respectively, when 2r ₂ ≧ R, Rθ> 2r ₂ ≧ (R−
r ₁ ) θ, and when 2r ₂ <R, it is preferable to satisfy the relationship of Rθ <2r ₂ . Assuming that the distance between the center of the deposition area and the rotation center of the substrate is L, L is R−
At about 0.5 × r ₁ , the deposition area becomes large, and the film formation rate on the substrate can be increased.

[0089] The above-described FIG. 19 or the first shown in FIG. 20, the mask material having a second opening 96 _1, 96 ₂ 9
The first of the compositions shown a 7 in FIG. 17 described above differs, the second target 95 _1, 95 ₂ and the first between the substrate 91, the second opening 96 _1, 96 ₂ each target 95 _1,
By disposed to face in a predetermined positional relationship to the 95 _2, can be formed first, the annular film of a multilayer structure in which a thin film made of the material of the second target are alternately laminated on the substrate. The substrate on which such an annular thin film is formed can be used as an antenna or a filter.

[0090]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

Example 1 First, as shown in FIG. 1, a disk-shaped substrate 29 made of SrTiO ₃ single crystal was supported and fixed on a substrate holder 19 arranged in a vacuum vessel 5. Subsequently, while supplying oxygen at a constant flow rate of 100 sccm into the container 5, the turbo pump 8 and the rotary pump 9
Was driven to exhaust the gas in the vacuum vessel 5 through the main valve 6 and the first exhaust pipe 7, and the inside of the vacuum vessel 5 was evacuated to 0.5 Torr. By driving a rotary pump (not shown) to exhaust the gas in the box 13 through a second exhaust pipe (not shown), the inside of the box 13 is evacuated to the same degree of vacuum as the vacuum vessel 5, and then the terminals 15a,
Each substrate disposed below the halogen lamp 14 was heated to a temperature of 700 ° C. by supplying electricity to the halogen lamp 14 through 15b to generate heat. Further, by rotating a rotating shaft 18 by driving a motor (not shown), the shutter 17 supported by the rotating shaft 18 is moved to a diameter 50 with a compound made of Y, Ba, and Cu disposed on the surface.
The target was located directly above a target 16 mm and 300 mm in length.

After the preparation for the film formation is completed, the laser oscillator 20 shown in FIG. 2 in which the height of the pair of main electrodes 23 facing each other and the distance between the electrodes are increased, is driven to 0.4 J. Fluence of 1 / cm ² and 1
A laser beam 28 having a beam area of 8 cm ² was oscillated. The laser beam 28 is reflected by the mirror 21, condensed at a predetermined focal length by the condenser lens 22, and modulated, so that the laser beam 28 has an average fluence of 1.2 J / cm ² or more and has a long length in the laser light incident direction. A laser beam 29 having a large area of 1 mm and a length orthogonal to the incident direction and having a length of 300 mm and an aspect ratio of 300 was irradiated onto the cylindrical target 16 through the transmission window 11 of the vacuum vessel 5 at a repetition frequency of 50 Hz. At this time, the holder 19 of the substrate is
It was moved at a speed of m / min.

The obtained YBCO superconducting thin film has a uniform thickness and a critical current density of 1 × 10 ⁶ at a critical temperature of 90K.
It had characteristics of A / cm ² or more.

Further, in Example 1 described above, when a similar film formation was carried out by holding ten disk-shaped substrates having a diameter of 50 mm in the holder 19, a superconducting thin film of YBCO having a thickness of 1 μm was formed. 20 substrates could be manufactured in one hour.

(Embodiment 2) As shown in FIG.
Laser beam 2 from _two laser oscillators 20 ₁ and 20 2
8 ₁ and 28 ₂ are oscillated simultaneously, and these laser beams 28
₁ and 28 ₂ are transmitted through the prisms 31 ₁ and 31 ₂ and the main prism 32 and are reflected on the mirror 21 to have an area of about 4
cm ² , and a laser beam having an average fluence of 0.6 J / cm ² . Further, the laser beam is condensed by the condenser lens 22 to form a pattern having an average fluence of 1.2 J / cm ² , a width of 0.4 mm, and a length of 290 mm. Except for the introduction, YB was applied to the substrate in the same manner as in Example 1 described above.
A CO superconducting thin film was formed.

The obtained YBCO superconducting thin film was uniform in thickness and had the same excellent superconducting properties as in Example 1.

(Embodiment 3) As shown in FIG. 8 described above, a concave lens 33 and a convex lens 34 are arranged in a vacuum vessel 5 and condensed by a condenser lens 22 arranged outside the vessel 5 and further transmitted. The laser beam 29 having passed through the window 11 is passed through the concave lens 33 and the convex lens 34 so that the average fluence is 1.2 J / cm ² , the width is 0.6 mm,
The laser beam 29 ′ is formed into a pattern having a length of 290 mm, and the laser beam 29 ′ is irradiated onto the target 16 similar to that of the first embodiment to form
A BCO superconducting thin film was formed on the substrate.

In the third embodiment, a large area YBC
An O superconducting thin film could be stably formed over a long period of time.

(Embodiment 4) As shown in FIG.
A plurality of image sensors 35 are arranged in a holder 19 having a length of 300 mm and a length of 300 mm, and a cylindrical target 16 having a diameter of 50 mm and a length of 300 mm in which Si is disposed on the surface is used. A SiO ₂ protective film was formed on the image sensor in the same manner as in Example 1 except that a laser beam having a pattern of 0.2 J / cm ² , a width of 1 mm, and a length of 290 mm was irradiated at a repetition frequency of 50 Hz. At this time, the holder was moved at a speed of 2 cm / min.

In Example 4 described above, the film was formed at a high reaction gas pressure, so that there was no escape of oxygen, and the particles such as atoms to be deposited had a high kinetic energy, so that sufficient migration was achieved even after reaching the substrate. Had energy. As a result, a dense and high-hardness film was obtained even when the film was formed at a relatively low temperature, and an image sensor having a protective film having excellent environmental resistance and abrasion resistance could be manufactured.

Further, in Example 4 described above, the thickness 1
240 image sensors having a μm protective film formed thereon could be manufactured in one hour.

It should be noted that Si ₃ N can be obtained by using nitrogen or ammonia instead of oxygen in the fourth embodiment.
₄ or SiN _x can be deposited on the surface of the image sensor. This film is more excellent in environmental resistance and abrasion resistance than SiO ₂ . If a hydrocarbon gas such as methane, ethylene, or acetylene is used as a reaction gas, SiC can be obtained, and this film is also excellent in environmental resistance and wear resistance.

(Embodiment 5) As shown in FIG. 22, a plurality of sliding members 37 mainly composed of iron are rotatably mounted on a holder 36 disposed in a vacuum vessel (not shown). Heated to a temperature of about 300 ° C., nitrogen was flowed into the vacuum vessel at a constant flow rate of 100 SCCM, the pressure in the vessel was set to 0.5 Torr, and Ti was disposed on the surface and had a diameter of 50 mm and a length of 300 mm. The cylindrical target 16 was used, and the average fluence of the cylindrical target 16 was 1.2 J / cm ² , the width was 1 mm, and the length was 29.
A TiN film was formed on the surface of each of the sliding members 37 in the same manner as in Example 1 except that a laser beam having a pattern of 0 mm was irradiated at a repetition frequency of 50 Hz. At this time, the respective sliding members 37 are rotated at 10 rpm by the holder 36.
While rotating at the above rotation speed, it was moved at a speed of 1 cm / min.

In Example 5 described above, since a film is formed at a high reaction gas pressure, there is no escape of nitrogen, and the particles such as atoms to be deposited have a high kinetic energy, so that the particles have a sufficient kinetic energy even after reaching the substrate. It had migration energy. As a result, even if the film is formed at a relatively low temperature, a dense and high-hardness film can be obtained, and a sliding member having no dimensional change and excellent in environmental resistance and wear resistance can be obtained.

In Example 5 described above, 60 sliding members containing iron as a main component and having a surface coated with a wear-resistant film could be manufactured in one hour.

In the fifth embodiment, the present invention is not limited to the sliding member, but can be applied to the production of a member requiring abrasion resistance such as a tool.

(Embodiment 6) A disc-shaped substrate 79 made of a single crystal of SrTiO ₃ having a diameter of 100 mm is supported and fixed in the concave portion of the substrate holder 74 arranged in the vacuum vessel 55 shown in FIGS. At the same time, the rotary shaft 73 was driven to rotate at a desired speed. Subsequently, oxygen is supplied to the container 55.
While supplying the gas at a constant flow rate of 100 sccm, the turbo pump 58 and the rotary pump 59 are driven to exhaust the gas in the vacuum vessel 55 through the main valve 56 and the first exhaust pipe 57. .5T
Set to a vacuum of orr. Further, a gas in the box 63 is exhausted through a second exhaust pipe (not shown) by driving a rotary pump (not shown), and the inside of the box 63 is evacuated to the same degree of vacuum as the vacuum vessel 55. , 6
The substrate 79 disposed below the halogen lamp 64 was heated to a temperature of 700 ° C. by supplying electricity to the halogen lamp 64 through 5b to generate heat. By driving a motor (not shown) to rotate the second rotating shaft 69, the shutter 68 supported by the rotating shaft 69 is positioned immediately above the three targets 66.

After the preparation for the film formation is completed, the laser oscillator 75 is driven to drive the laser beam 80.
Oscillated. The laser beam 80 was reflected by a mirror 76 and focused by a condenser lens 77 at a predetermined focal length. The focused laser beam 80 was introduced into the container 55 through the transmission window 61 of the vacuum container 55. The introduced laser beam 80 is reflected by a 20-surface polygon mirror 78 rotating at a speed of 120 rpm as shown in FIG.
Three disk-shaped targets 6 each supported by a rotating shaft 67 and having a compound composed of Y, Ba, and Cu disposed on the surface thereof
6 was irradiated. When the evaporation of the target component from each target 66 is stabilized, the motor (not shown) is driven to rotate the rotating shaft 69, thereby opening the shutter 68 supported by the rotating shaft 69, Substrate 79
Of the mask material 71 arranged at a distance of 1 cm from
A YBCO superconducting thin film was formed on the rotating substrate 79 through a fan-shaped opening 70 formed in the direction in which the two targets 66 were arranged.

The obtained YBCO superconducting thin film has a diameter of 1
It had a thickness distribution of 1.0 ± 0.05 μm over the entire surface of 00 mm, and it was confirmed that the thickness was uniform. The superconducting thin film of YBCO had a characteristic of a critical current density of 1 × 10 ⁶ A / cm ² or more at a critical temperature of 90K.

A YBCO film was formed on a rectangular substrate instead of the disk-shaped substrate, processed into a spiral or meandering shape, and evaluated as a current-limiting element. Excellent current limiting characteristics were exhibited without any occurrence of cracks.

(Embodiment 7) As shown in FIG. 17, the disc-shaped substrate 91 made of SrTiO ₃ single crystal held in a holder (not shown) in a vacuum vessel (not shown)
It was rotated at a speed of 00 rpm. Subsequently, while supplying oxygen into the vessel at a constant flow rate of 100 sccm, the vessel was evacuated by an exhaust system (not shown) to a vacuum of 0.5 Torr. Subsequently, a laser beam 92 which is focused by an incident angle of 60 ° around incident on the polygon mirror 93 of the 20 surface rotating at a speed of 120rpm in the counterclockwise direction, the laser beam 94 with different fluence _1, 94 ₂ Ono Y, B
a, a first target 95 ₁ having a compound composed of Cu and Cu on its surface and a second target 95 ₂ having Ce as a pinning center disposed on its surface are respectively irradiated with the substrate 91.
A thin film was formed on the lower surface of the. The targets 95 ₁ and 95
₂ is symmetrically disposed below the substrate 91 with respect to the center of rotation.

In Example 7 described above, a YBCO superconducting thin film in which a different phase serving as a magnetic flux pinning center was finely dispersed could be formed on the substrate.

Example 8 As shown in FIG. 17, a disk-shaped substrate 91 made of SrTiO ₃ single crystal and having a diameter of 50 mm was held by a holder (not shown) in a vacuum vessel (not shown). . First target 95 ₁ having a compound composed of Y, Ba, and Cu disposed on the surface thereof and Pr, Ba, Cu
The second target 95 ₂ arranged on the surface of the compound consisting disposed respectively at a distance of 4cm below the substrate 91. The targets 95 ₁ and 95 ₂ are arranged below the substrate 91 symmetrically with respect to the center of rotation. Disc-shaped mask material 97 shown in FIG.
Was disposed between the substrate 91 and each of the targets 95 ₁ and 95 ₂ so as to be closer to the lower portion of the substrate 91 by a distance of 1 cm. The mask material 97 has the same dimensions as the substrate, the first opening 96 ₁ having θ of 30 °, the second opening having θ of 25 °, and having a larger diameter in the diameter direction than the first opening 96 _1. It has parts 96 ₁ and 96 ₂ .

First, while heating the substrate 91 to 700 ° C. with a halogen lamp (not shown), about 0.05 rpm
At the speed of Subsequently, one oxygen was placed in the container.
While supplying at a constant flow rate of 00 sccm, the air was exhausted by an exhaust system (not shown) to a degree of vacuum of 0.5 Torr. Subsequently, the condensed laser beam 92 is incident on a 20-sided polygon mirror 93 rotating at a speed of 120 rpm in the counterclockwise direction at an incident angle of about 60 °, and a laser beam 94 ₁ having a fluence of 1.5 J / cm ^2. Y a at a repetition frequency of 50 Hz, Ba, irradiating the compound of Cu to ₁ the first target 95 arranged on the surface, fluence laser beam 94 ₂ 1.0 J / cm ² 50 Hz
The of Pr at a repetition frequency, irradiated Ba, a compound consisting of Cu to ₂ the second target 95 arranged on the surface, of the respective target 95 _1, 95 ₂ the mask material 97 and particles such as vaporized atoms from 1, second openings 96 ₁ , 9
It was formed by depositing on the substrate 91 through 6 _2. At this time, YBa ₂ Cu ₃ O _x which is a superconductor is provided on the substrate 91.
PrBa ₂ Cu ₃ O _x thin film as an insulator
An annular thin film having a multilayer structure formed alternately at a speed of 00 nm / min was formed.

According to the eighth embodiment, a member in which a coil and a capacitor are connected in series on the substrate 91 can be obtained. This member has almost no contact resistance and has a small loss because the coil and the capacitor are connected, and has a high Q value because the coil is formed of a superconductor. Accordingly, such a member can be used for an antenna for a high-frequency device, for example, an MRI pickup coil, a filter for a communication device, an antenna, and the like.

When the member of Example 8 was used as an MRI pickup coil, the SN ratio was improved by one digit or more as compared with the case where a conventional Cu coil was used, and a clear image was obtained even with a magnetic field of 1.5 Tesla. Could be obtained.

In the eighth embodiment, the superconductor is not limited to YBCO, but BiSrCaCuO, BiPb
SrCaCuO, TlBaCuO can be used,
Insulation resistance does not react with superconductors and is similar in crystal structure.
For example, SrTiO ₃ , MgO, YSZ can be used.

Further, the multilayer annular thin film formed by the method of the eighth embodiment is characterized in that it is very thin and has a large inductance and capacity, and can be used in a power supply system which is small and in which a relatively large current flows. In this case, the coil does not need to be a superconductor, and Ag, Cu,
A conductive material such as Al may be used. There is no limitation on the crystal structure of the insulating material, and SiO ₂ , Al ₂ O ₃ , Y ₂ O ₃ , YSZ
Any material having a high specific resistance may be used.

[0119]

As described above, according to the present invention, it is possible to provide a film forming method capable of stably and mass-producing a thin film having a large area over a long period of time.

Further, according to the present invention, a thin film such as a superconductor having a high critical current density even in a magnetic field in which a second component such as an impurity is uniformly dispersed over a large area is formed. It is possible to provide a film forming method capable of performing the method.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an apparatus used for a film forming method according to the present invention.

FIG. 2 is a perspective view of a main part of a laser oscillator incorporated in the apparatus of FIG.

FIG. 3 is a main part front view of another laser oscillator incorporated in the apparatus of FIG. 1;

FIG. 4 is a diagram showing a state in which a cylindrical lens is arranged on the laser oscillator shown in FIG. 3 and a laser beam is focused.

FIG. 5 is a perspective view for explaining a state in which a target is irradiated with a laser beam to evaporate a target material in the film forming apparatus of FIG. 1;

FIG. 6 is a perspective view showing another laser beam irradiation mode to a target.

FIG. 7 is a schematic view showing a mode in which a laser beam is irradiated using two laser oscillators.

FIG. 8 is a perspective view showing another irradiation mode of a laser beam to a target.

FIG. 9 is a sectional view showing an apparatus used in another film forming method according to the present invention.

FIG. 10 is a perspective view showing a main part of the film forming apparatus of FIG. 9;

11 is a plan view of the film forming apparatus of FIG. 9 as viewed from a mask material side.

FIG. 12 is a plan view showing an opening shape of a mask material incorporated in the film forming apparatus of FIG. 9;

FIG. 13 is a plan view showing an opening shape of a mask material incorporated in the film forming apparatus of FIG. 9;

FIG. 14 illustrates a case where a target is irradiated with a laser beam.
FIG. 3 is a plan view for explaining a laser beam irradiation position.

FIG. 15 is a perspective view showing a linear laser beam used in the present invention.

FIG. 16 is a diagram of the linear laser beam of FIG. 15 as viewed from above.

FIG. 17 is a plan view showing a state in which targets having different compositions are irradiated with laser beams having different fluences in the film forming method according to the present invention.

FIG. 18 is a plan view for explaining changing the angle of incidence of a laser beam on a polygon mirror when targets having different compositions are arranged opposite to those in FIG. 17;

FIG. 19 is a plan view showing a mask material having two openings.

FIG. 20 is a plan view showing another mask material having two openings.

FIG. 21 is a perspective view for explaining a film forming method according to a fourth embodiment of the present invention.

FIG. 22 is a perspective view for explaining a film forming method according to a fifth embodiment of the present invention.

FIG. 23 is a diagram showing a thickness distribution of a thin film formed using a conventional single target.

FIG. 24 is a diagram showing a thickness distribution of a thin film formed using a plurality of targets of the present invention.

[Explanation of symbols]

5 and 55 ... vacuum vessel, 11, 61 ... transmission window, 114,64 ... halogen lamp, 16,66,95 _1, 95 ₂ ... target, 19,74 ... substrate holder, 20, 20 _1, 20 _2, 75 ... a laser oscillator, 27,79,91 ... substrate, 29,80,92,94 _1, 94 ₂ ... laser beam, 30,72,81,98 _1, 98 ₂ ... deposition area, 70,82,96 _1, 96 ₂ ... Opening parts, 71,97 ... Mask material, 78,93 ... Polygon mirror.

Claims (4)

[Claims] 1. A performs ablation pulsed laser beam is irradiated to the solid material, whereby in the method of forming a film by adhering vaporized material to the substrate, has a 0.8 J / cm ² or less of the average fluence From a laser beam having an area of 4 cm ² or more and 1 J / cm 2
A film forming method, comprising: irradiating the solid material with a laser beam having a mean fluence of ² or more and a cross-sectional shape having an aspect ratio of 50 or more. 2. A method for irradiating a solid material with a pulsed laser beam to perform ablation, and depositing a substance evaporated by the method on a substrate, thereby forming a film. A film forming method comprising: evaporating the solid raw material simultaneously or sequentially from a plurality of places after disposing a mask having an opening. 3. The laser beam according to claim 2, wherein a ratio (L / W) of a width (W) to a length (L) of the irradiation surface of the substrate is 10 times or more.
The film forming method according to the above. 4. A method of performing ablation by irradiating a solid-state raw material with a pulsed laser beam and depositing a substance evaporated by this on a substrate, wherein the substrate is rotated at a desired speed while rotating the substrate at a desired speed. A film forming method characterized by simultaneously or sequentially irradiating a plurality of solid raw materials disposed below a substrate with laser beams having different fluences.