JPH08269710A - Reactive sputtering device and reactive sputtering method as well as reactive vapor deposition device and reactive vapor deposition method - Google Patents

Abstract

PURPOSE: To decrease the fluctuations in the compsn. in the thickness direction of films in the case where the films are simultaneously formed on the surfaces of many substrates or the films are formed on a large-area substrate in a reactive sputtering method and reactive vapor deposition method. CONSTITUTION: A device which executes sputtering while rotating a substrate holder 53 holding the plural substrates 1, or a device which executes sputtering while moving the large-area substrate in parallel right above a target or a device for executing vapor deposition while moving the large-area substrate in parallel right above a vapor deposition source is provided with a mask means 63 covering the surface of the substrate and is provided with an aperture near a position facing the target 51 of the mask means or the vapor deposition source. The deposition of the active species of reactive gases is suppressed on the surface of the substrate 1 covered with the mask means 63 and the sputtered films or vapor deposited films are formed on the surface of the substrate 1 near the aperture of the mask means 63 when the active species depositable as solids on the substrate are used as the reactive gases.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for forming a thin film containing a plurality of elements such as carbides, borides and phosphides by reactive sputtering or reactive vapor deposition, and a film formation using this apparatus. And how to do.

[0002]

2. Description of the Prior Art Compound thin films of carbides, borides, phosphides, etc. have various advantages in electrical properties, optical properties, chemical properties, mechanical properties, etc. that metal thin films cannot provide. It is widely used in various fields and its application range is expected to expand further in the future.

There are many methods for forming these compound thin films, but as a method for forming a film on the surface of a semiconductor substrate, a glass substrate, electronic parts, tools, etc., there are chemical vapor deposition (CVD) and sputtering or vapor deposition. It is roughly classified into physical vapor deposition (PVD).

The CVD method has a feature that a relatively thick film can be formed at low cost, but generally, the substrate itself is 1000 ° C.
It is necessary to heat to the above high temperature. For this reason, the PVD method is widely used, which allows film formation on a substrate at a relatively low temperature, except when forming a film on the surface of a heat-resistant substrate.

The PVD method has a drawback that the film formation rate is slower than that of the CVD method, but it is easy to control the composition and thickness of the film as a functional material, and it is possible to obtain a high-quality film containing few impurities. There are advantages.

However, since the compounds such as the above-mentioned carbides generally have high melting points and hardness, it is rare to use these compounds as a sputtering target or a vapor deposition source when the PVD method is used. For example, a carbide thin film can be PVD
When formed by the method, a metal is generally used as a target or a vapor deposition source, and a metal carbide thin film is generally obtained by reacting with a hydrocarbon gas during sputtering or vapor deposition. In order to obtain a film having a stoichiometric composition, it is usually necessary to chemically activate the reaction gas by discharging it. In the reactive sputtering method, hydrocarbons are activated by plasma of Ar gas. On the other hand, in the reactive vapor deposition method (reactive ionization vapor deposition method and reactive ion plating method), a hydrocarbon gas or the like is used by using a vapor deposition apparatus or an ion plating apparatus provided with a discharge electrode or a thermionic emission filament. And ionize the reaction gas and the vapor deposition material.

A configuration example of a reactive sputtering apparatus for mass production
5 and 6 respectively. The example of FIG. 5 is an apparatus for simultaneously forming a film on a plurality of substrates by using a target 51 having a small area, and holding a plurality of substrates 1 in a substrate holder 53,
Sputtering is performed while rotating the substrate holder 53. The example of FIG. 6 is an apparatus for forming a film on a large-area substrate using a small-area target, and has a configuration in which the substrate 1 passes directly above the target 51 during sputtering. With these devices,
The substrate is revolved and moved to form a film having a uniform thickness.

However, when a compound thin film of a carbide or the like is formed by reactive sputtering, the above-mentioned mass production apparatus has a problem that composition variation occurs in the thickness direction of the film. FIG. 7 schematically shows a region where plasma (Ar + reactive gas) and reactive gas active species exist between the target 51 and the substrate holder 53 of the reactive sputtering apparatus of FIG.
Since the area A in FIG. 7 is directly above the target 51, a film having a substantially stoichiometric composition is formed. On the other hand, B of FIG.
In the region, the number of particles flying from the target is significantly smaller than in the region A, while the amount of active species in the reaction gas is slightly smaller than in the region A. Therefore, when a hydrocarbon gas is used as the reaction gas, carbides having a stoichiometric composition are deposited in the A region, but plasma CV is deposited in the B region.
Due to the same reaction as in the D method, substantially only carbon is deposited, which largely deviates from the stoichiometric composition. Therefore, as the substrate holder 53 rotates, the composition periodically changes in the film thickness direction. Even in the apparatus for performing reactive sputtering while moving the substrate 1 shown in FIG. 6, the amount of target particles flying to the surface of the substrate greatly fluctuates according to the distance from the target 51. Since the amount is not significantly affected by the distance from the target, the composition variation also occurs in the film thickness direction.

Such a composition change is caused by active species such as hydrocarbon, borohydride, and hydrogen phosphide that are generated by glow discharge decomposition and are deposited on the substrate surface as a solid, that is, a reaction similar to plasma CVD. It occurs when a reactive gas that can deposit active species by the mechanism is used. And, such a composition variation is caused by a reactive physical vapor deposition method in which physical vapor deposition and chemical vapor deposition proceed at the same time, that is, in addition to the reactive sputtering method,
It also occurs in the reactive vapor deposition method.

[0010]

SUMMARY OF THE INVENTION An object of the present invention is to form a film in the reactive sputtering method and the reactive vapor deposition method when forming a film on a large number of substrate surfaces at the same time or when forming a film on a large area substrate. The purpose is to reduce the composition variation in the thickness direction.

[0011]

This and other objects are achieved by any of the following constitutions (1) to (10). (1) A mask that covers the surfaces of a plurality of substrates in the vicinity of the surface of the substrate holder by periodically rotating the substrate holder that holds the plurality of substrates during sputtering to face the target. A reactive sputtering apparatus having a means, the mask means having an opening near a position facing the target. (2) The reactive sputtering apparatus according to (1), wherein the diameter of the opening of the mask means is not less than the substrate diameter and not more than twice the target diameter. (3) At the time of sputtering, the substrate is moved in parallel so as to pass through the position facing the target, and mask means for covering the substrate surface is provided near the surface of the substrate. The mask means is provided near the position facing the target. A reactive sputtering apparatus having an opening. (4) The opening diameter of the mask means in the substrate moving direction is equal to or larger than the target length in the substrate moving direction and equal to 2 of this target length.
The reactive sputtering device according to the above (3), which is no more than double. (5) The distance between the substrate surface and the mask means is 0.1 to 30 mm
The reactive sputtering apparatus according to any one of (1) to (4) above. (6) Using the reactive sputtering apparatus according to any one of the above (1) to (5), using a reactive gas that allows active species to be deposited as a solid on the substrate, and covering the substrate with a mask means to form a reactive gas on the substrate surface. A reactive sputtering method for suppressing deposition of active species and forming a sputtered film on the surface of a substrate in the vicinity of an opening of a mask means. (7) The structure is such that the substrate moves in parallel at a position facing the deposition source during vapor deposition, and mask means for covering the substrate surface is provided near the substrate surface, and the mask means has an opening near the position facing the deposition source. And a reactive vapor deposition device. (8) Two straight lines that respectively connect both edges of the opening of the mask means and the center of the surface of the vapor deposition source in a cross section when the mask means is cut along a plane including the substrate moving direction, the center of the opening of the mask means, and the vapor deposition source The reactive vapor deposition device according to (7) above, wherein the angle between the two is 90 ° or less. (9) The distance between the substrate surface and the mask means is 0.1 to 30 mm
The reactive vapor deposition device according to (7) or (8) above. (10) Using the reactive vapor deposition apparatus according to any one of (7) to (9) above, using a reactive gas that allows active species to be deposited as a solid on the substrate, and covering the substrate with a mask means to form a reactive gas on the substrate surface. A reactive vapor deposition method for suppressing deposition of active species and forming a vapor deposition film on a substrate surface in the vicinity of an opening of a mask means.

[0012]

In the present invention, in the reactive sputtering apparatus and the reactive vapor deposition apparatus, mask means having an opening is provided near the substrate. This mask means suppresses the deposition of the reactive gas active species on the surface of the substrate far from the target or the vapor deposition source, and forms a sputtered film or a vapor deposited film near the stoichiometric composition on the substrate surface at the opening. This makes it possible to suppress composition fluctuations in the thickness direction of the film when the substrate holder is rotated to form a film on the surfaces of a plurality of substrates or when the film is formed while moving a large-area substrate.

Moreover, by providing such a mask means, it is possible to suppress the composition variation and improve the crystallinity of the film. This improvement in crystallinity is considered to be because the mask means suppresses the ions and electrons incident on the substrate.

[0014]

Specific Structure The specific structure of the present invention will be described in detail below.

FIG. 1 shows an end view of a structural example of the reactive sputtering apparatus of the present invention. In this apparatus, a plurality of disk-shaped substrates 1 are held on the surface of a disk-shaped substrate holder 53, and during sputtering, the substrate holders rotate and each substrate surface periodically faces the target 51.

A disk-shaped mask means 63 is provided near the surface of the substrate holder 53. The mask means 63 is
The shape, size and arrangement are determined so as to cover the surfaces of the plurality of substrates held on the surface of the substrate holder. The mask means 63 has an opening near the position facing the target, that is, immediately above the target. The opening of the mask means may be appropriately determined, and for example, may be circular or rectangular, but preferably has a fan shape as shown in FIG. The pair of arc-shaped edges of the fan-shaped opening are preferably concentric with each other about the rotation axis of the substrate holder.

The distance D between the substrate surface and the mask means is preferably 0.1 to 30 mm, more preferably 1 to 10 mm. If this distance is too small, the substrate may come into contact with the mask means, and if this distance is too large, the effect of preventing the reactive gas active species from being deposited by the mask means becomes insufficient. The distance between the substrate surface and the target 51 is usually about 80 to 150 mm.

The size of the opening of the mask means may be appropriately determined in accordance with various conditions such as the size and positional relationship of the substrate and the target so that composition variation does not easily occur. The diameter may be twice the diameter or less, but the following dimensions are preferable.

A direction passing through the rotation center of the substrate holder (hereinafter,
The opening diameter (diameter in the vicinity of the center of the opening) measured in the holder radial direction is preferably at least 1 times the substrate diameter in the holder radial direction,
It is more preferably 1.2 times or more, and preferably 2 times or less, and more preferably 1.5 times or less of the target effective diameter in the holder radial direction. When the openings are fan-shaped, the diameter of the openings in the holder radial direction is the length L ₁ shown in FIG. The target effective diameter is usually equal to the target diameter, but in the case where a part of the target surface is covered by the rotary shutter 54 as shown in FIG. 1 or the like, it means the apparent target diameter seen from the substrate side. .

On the other hand, the opening diameter in the direction orthogonal to the holder radial direction (hereinafter referred to as the holder rotation direction) (the diameter near the center of the opening, L ₂ in FIG. 9) can be appropriately determined according to the substrate shape. Good. For example, when the substrate has a normal shape, that is, an isotropic shape such as a disc shape, the diameter may be equal to the diameter of the opening in the holder radial direction. It is preferable to determine the diameter of the opening in the holder rotation direction so that the angles α, β, and γ shown satisfy the formula β ≦ α ≦ 2γ. In FIG. 9, the opening, the substrate 1, and the target 51 are shown in an overlapping manner. However, the target is shown as the effective diameter. In the figure, an angle α is an angle formed by two straight lines (which are tangents in the illustrated example) drawn from a point O, which is the center of rotation of the substrate holder, to both ends of the arc-shaped edge of the opening, whichever is closer. is there. The angle β is an angle between two tangent lines drawn from the point O to the outer peripheral edge of the substrate. The angle γ is an angle between two tangent lines drawn from the point O to the outer peripheral edge of the target.

If the diameter of the opening is too small in each of the above directions, the film formation rate may be low, and a film having a uniform thickness may not be obtained. If the diameter of the opening is too large, the compositional variation in the thickness direction of the film becomes large.

The opening of the mask means is not limited to the form in which a part of the mask means is perforated as shown in the drawing, but may be formed by cutting out the outer edge of the mask means.

In such an apparatus having a structure in which the substrate holder rotates, the substrate diameter is usually about 4 to 6 inches, and the target diameter is usually about 8 to 12 inches. The distance between the centers of the two substrates facing each other with the center of rotation of the substrate holder in between is usually about 300 to 800 mm.

The material of the mask means used in the reactive sputtering apparatus is not particularly limited, but SUS30 is used because it is easy to process and is the same material as a normal vacuum chamber.
4, stainless alloys such as SUS316 and the like are preferable.

In the apparatus shown in FIG. 1, a slide shutter 61 is provided inside the vacuum chamber 50. The slide shutter 61 is slidable in the left-right direction in the figure, and during pre-sputtering, the slide shutter 61 is moved between the substrate 1 and the target 51 to prevent film formation on the substrate surface. Then, after the end of the pre-sputtering, the slide shutter 61 is moved to the position shown in the figure. The pre-sputtering is a step of sputtering the target in order to remove the adsorbed gas and the altered layer on the surface of the target. At this time, only Ar gas is introduced to cause discharge. In the present invention, instead of providing the slide shutter 61, a shutter mechanism may be provided at the opening of the mask means 63, and the opening of the mask means may be closed during pre-sputtering.

In the reactive sputtering apparatus of the present invention, the structure other than the mask means 63 is not particularly limited and various structures can be adopted. For example, the device of FIG. 1 can be equipped with two or more types of targets, and the targets 51,
A rotary shutter 54 having an opening having substantially the same diameter as 52 allows switching between both targets. The high frequency power from the high frequency power source 57 is supplied to the matching circuit 56.
And is supplied to an arbitrary target by the changeover switch 55.

Sputtering is performed, for example, in the following procedure. First, the high-vacuum exhaust system 58 composed of a turbo molecular pump and a rotary pump is used for the vacuum chamber 5
The inside of 0 is evacuated to a high vacuum state, and the temperature of the substrate is adjusted to a predetermined temperature by a heater built in the substrate holder 53. Next, a constant flow rate of Ar gas is introduced by the mass flow controller 59, and the inside of the vacuum chamber is brought to a predetermined pressure by the conductance adjusting valve 62. Then, the slide shutter 61 is moved as described above to perform pre-sputtering, and then the mass flow controller 6
At 0, a constant flow rate of reaction gas is introduced, and the conductance adjusting valve 62 is readjusted to bring the inside of the vacuum chamber to a predetermined pressure. After starting the rotation of the substrate holder 53, the slide shutter 61 is moved to the position shown in the figure to start the film formation by the reactive sputtering.

FIG. 2 shows an end view of another structural example of the reactive sputtering apparatus of the present invention. This equipment is
The structure is such that the substrate 1 moves in parallel directly above the target 51. With this type of device, where the substrate moves in parallel to form a film on a substrate with a larger area than the target,
The substrate is moved in the longitudinal direction. The width of the target (length in the depth direction in the figure) is set to be approximately the same as the width of the substrate. In such a device, a long flexible film is also used as the substrate.

A mask means 63 for covering the surface of the substrate 1 is provided near the surface of the substrate 1. The mask means 63 is
An opening is provided near the position facing the target, that is, immediately above the target. The opening of the mask means
Usually, it is rectangular, and the diameter of the opening in the depth direction in the figure may be about the same as the width of the substrate. The opening diameter in the substrate moving direction is preferably 1 of the target length in the substrate moving direction.
It is at least twice, more preferably at least 1.2 times, and preferably at most 2 times, more preferably at most 1.5 times. If the diameter of the opening in the substrate moving direction is too small, it is necessary to slow down the moving speed of the substrate, resulting in low productivity.
On the other hand, if the opening diameter is too large, the composition variation in the thickness direction of the film becomes large.

The opening of the mask means may be formed by punching one plate-like body, and two plate-like bodies are arranged with a gap therebetween, and the space between both plate-like bodies is used as the opening. You may.

In the apparatus configured to perform sputtering while moving the substrate in this way, the target length in the substrate moving direction is usually about 5 to 10 inches.
The distance between the substrates is about the same as in FIG. The moving speed of the substrate is about 10 to 200 mm / minute.

The range of the distance D between the substrate surface and the mask means and the reason for the limitation are the same as in the case of the apparatus of FIG.

The members in FIG. 2 designated by the same reference numerals as those in FIG. 1 are the same members as in FIG.

FIG. 3 shows an end view of a constitutional example of the reactive vapor deposition device of the present invention. In the present invention, the reactive vapor deposition method is a vapor deposition method of ionizing a vapor deposition material and a reactive gas during vapor deposition, and specifically, a reactive ionization vapor deposition method and a reactive ion plating method.

The apparatus shown in FIG. 3 has a structure in which the substrate 1 moves parallel to the position directly above the vapor deposition source 71 in the crucible during vapor deposition. In a type in which the substrate is moved in parallel to form a film on a large-area substrate like this apparatus, the substrate is moved in the longitudinal direction. In such a device, a long flexible film is also used as the substrate.

A mask means 63 for covering the surface of the substrate 1 is provided near the surface of the substrate 1. The mask means 63 is
An opening is provided near a position facing the vapor deposition source, that is, immediately above the vapor deposition source. The shape of the opening of the mask means is usually rectangular, and the diameter of the opening in the depth direction in the drawing may be about the same as the width of the substrate. The opening diameter in the substrate moving direction is determined so that the angle θ in the figure is preferably 90 ° or less, more preferably 60 ° or less. The angle θ is
The angle formed by two straight lines connecting the edges of the mask means opening and the center of the evaporation source surface in a cross section when the mask means is cut along a plane including the substrate moving direction, the center of the opening of the mask means, and the evaporation source. Is. If the angle θ is too small,
Since it is necessary to slow down the moving speed of the substrate, the productivity becomes low. On the other hand, if the angle θ is too large, the compositional variation in the film thickness direction becomes large. In the apparatus having such a configuration, the distance between the vapor deposition source and the substrate is usually 800 to
It is about 1500 mm. The moving speed of the substrate is usually about 10 to 300 mm / minute. Note that in such a vapor deposition apparatus, a plurality of vapor deposition sources may be arranged in the width direction of the substrate.

The range of the distance D between the substrate surface and the mask means and the reason for limiting the same are the same as in the case of the apparatus of FIG.

The mask means used in the reactive vapor deposition apparatus may be made of the same material as the mask means used in the sputtering apparatus.

In vapor deposition, first, the vacuum chamber 50
After making the inside a predetermined degree of vacuum, the mass flow controller 6
The reaction gas is introduced through 0. Next, the electron gun power supply 7
By the electron beam from the electron gun 78 connected to 7,
The vapor deposition source 71 is heated. This heating is for cleaning the vapor deposition source and the like as in the above-mentioned pre-sputtering. At this time, the shutter 74 is directly above the vapor deposition source and prevents deposition of the vapor deposition material on the substrate or the like. Next, the shutter 74 is moved from directly above the vapor deposition source to start vapor deposition. At this time, the vapor deposition material is ionized by the discharge electrode 72, and the reactive gas is turned into plasma to generate active species. If a bias voltage is applied to the substrate holder 53 by the ion acceleration power supply 79 during vapor deposition, reactive ion plating is possible.

The members in FIG. 3 designated by the same reference numerals as those in FIG. 1 are the same members as in FIG.

As described above, in the present invention, the mask means is provided in the reactive physical vapor deposition method in which physical vapor deposition and chemical vapor deposition proceed simultaneously. INDUSTRIAL APPLICABILITY The present invention is applied to the production of metal compounds (including semi-metal compounds), but in particular, carbides (TiC, SiC, TaC) that are difficult to form by a normal sputtering method or vapor deposition method due to their high melting points and hardness. , WC, Hf
C, B ₄ C, etc., boride (LaB ₆ , TiB ₂ , Ta)
B, ZrB, etc.), phosphide (GaP, InP, BP, etc.)
It is suitable for film formation.

The reactive gas used in the present invention is a gas which allows active species to be deposited as a solid on the substrate during sputtering or vapor deposition. The reaction gas preferably used is CH ₄ , C ₂ H ₆ , C ₂ H ₄ , C ₂ H _{2 in} the case of forming a carbide film.
In the case of boride film formation, B ₂ H _{6 and the} like can be mentioned, and in the case of phosphide film formation, PH _{3 and the} like can be mentioned.

Compounds other than the above, such as GaA
It can also be applied to film formation of s, ZnS, ZnSe, ZnTe and the like. In the case of these compounds, the reaction gas is As
H ₃ , H ₂ S, H ₂ Se, H ₂ Te and the like are preferably used.

In the present invention, the film is not limited to the above compounds, and even a film having a stoichiometric composition can be formed uniformly.

The present invention is suitable for forming a hard coat on the surface of electronic parts and tools, and is, for example, Japanese Patent Application No. Hei 6
It is also suitable for forming an emitter of a cold cathode electron source element disclosed in, for example, No. 337964. As an example of a method of manufacturing this emitter, a method of applying heat treatment to a Ni / TiC multilayer film is disclosed. However, if the present invention is applied to the formation of this multilayer film, a uniform TiC layer can be obtained and
The crystallinity of iC and Ni is improved.

[0046]

EXAMPLES The present invention will be described in more detail below by showing specific examples of the present invention.

Example 1 A titanium carbide thin film was formed by the procedure described above using the reactive sputtering apparatus having the structure shown in FIG. The film formation was performed under the following conditions.

Substrate holder: diameter 800 mm, rotation speed 6 rp
m, number of substrates held, distance between centers of opposing substrates across the center of rotation: 500 mm, substrate: glass, diameter 3 inches, thickness 0.5 mm, target: purity 99.9% or more Ti, diameter 8 inches , Effective diameter 190 mm, thickness 3 mm, mask member: SUS304, diameter 800 mm, thickness 4 mm, mask member opening: fan-shaped, L ₁ = 100 mm in FIG.
(L ₁ is 1.31 times the substrate diameter), α = 60 in FIG.
°, β = 15 °, γ = 40 °, L ₂ = 147.5 mm (L
₂ is 1.9 times the substrate diameter), distance between mask member and substrate surface: 2 mm, distance between target and substrate surface: 100 mm, ultimate pressure: 1 × 10 ^-7 Torr, substrate temperature: 300 ° C., Ar flow rate : 47 sccm, pre-sputtering condition: 0.5 Pa, 10 minutes, reaction gas: C ₂ H ₂ , reaction gas flow rate: 3 sccm, high frequency power: 1 kW, sputtering time: 20 minutes

For comparison, a thin film was formed under the same conditions as above except that the mask means 63 was removed from the apparatus shown in FIG.

The thin film formed by using the apparatus having the mask means according to the present invention has a thickness of 400 nm, no composition change in the thickness direction is observed, and is substantially composed of polycrystalline TiC. It was And the crystallinity was good. On the other hand, in the thin film formed by using the apparatus having no mask means, a large composition variation in the thickness direction was recognized. Specifically, a structure close to a laminated structure of a thin layer of fine polycrystalline TiC and a thin layer of hydrogenated amorphous carbon was recognized. With such a structure, the original characteristics of the TiC film, such as good electron emission characteristics, heat resistance, and high hardness, cannot be obtained. A comparison of both thin films is shown below.

Composition (Ti / C) was measured by a fluorescent X-ray method. Inventive Example: 1.01 Comparative Example: 0.43

It was calculated from the average crystal grain size (200) plane peak by the Scherrer's formula. Inventive Example: 310 nm Comparative Example: 60 nm

Vickers hardness Example of the present invention: 3300 Comparative example: 700

As described above, the thin film produced by the present invention has a substantially stoichiometric composition and a large average crystal grain size.
High hardness. On the other hand, in the thin film of the comparative example produced by the apparatus having no mask means, the composition deviation is remarkable. Further, in the thin film of the comparative example, since the crystal grains are fine, the ratio of crystal grain boundaries becomes high, and the original characteristics of the crystal cannot be sufficiently realized. Further, the thin film of the comparative example does not have the expected hardness.

Example 2 Using the same reactive sputtering apparatus as in Example 1, a Ni / TiC multilayer film was formed on the glass substrate surface as an emitter material for cold cathode electron source elements. The dimensions of the substrate were the same as in Example 1. The stacking order is Ni layer → T
The iC layers were arranged in this order, and the number of laminated layers was 10 for each layer.

Ni (target diameter: 8 inches, thickness: 3 mm) having a purity of 99.9% or higher was used as the Ni layer target, the substrate temperature was 250 ° C., the Ar gas flow rate was 50 sccm, and the anode side was grounded to 1
It was formed to a thickness of 20 nm per layer. Other conditions were the same as in Example 1.

The TiC layer substrate temperature is set to 250 ° C., the substrate side is grounded,
Each layer was formed with a thickness of 5 nm. Other conditions are Example 1
Same as.

The thickness of each layer was controlled as follows. A monolayer film having a thickness of about 1 μm was previously formed for each layer under the same conditions as above, and the film formation rate was calculated from the thickness of each monolayer film and the film formation time. Then, from these film forming rates, the times required for forming films with thicknesses of 20 nm and 5 nm were calculated, and were taken as the film forming time of each layer in the multilayer film.

When the Ni / TiC multilayer film thus formed is used as an emitter for a cold cathode electron source element, it is necessary to perform fine shape processing. This processing is usually performed by chemical etching, but since TiC is chemically stable, chemical etching is difficult. Therefore, heat treatment is performed at about 500 ° C. to change the multilayer film into a structure in which TiC fine particles are dispersed in Ni. This enables processing using a phosphoric acid-nitric acid-based Ni etchant.

For this reason, the above-mentioned multilayer film has a thickness of 500.
C., heat treatment was performed for 1 hour. The thin film after the heat treatment had TiC particles with a particle size of about 5 nm dispersed in Ni. After the heat treatment, X-ray diffraction was performed to evaluate the crystallinity. For comparison, a device having no mask means was used, and other conditions were the same as above (however, the thickness of the TiC layer was 10 nm).
Then, a multilayer film was formed, and this was also subjected to the above heat treatment and then subjected to X-ray diffraction. The X-ray diffraction charts of both multilayer films are shown in FIG. From the figure, it is understood that the crystallinity of each of TiC and Ni is dramatically improved by providing the mask means. Specifically, although the TiC layer was formed thinner in the inventive example than in the comparative example, the TiC (2
The (00) plane has a large peak intensity, and the T
The peak on the iC (111) plane has almost disappeared. That is, in the example of the present invention, the (100) orientation is remarkably improved. Further, similarly, it can be seen that in the present invention example, the Ni (100) orientation is remarkably improved as compared with the comparative example.

Example 3 A titanium boride thin film was formed by the procedure described above using the reactive sputtering apparatus having the structure shown in FIG. The film formation was performed under the following conditions.

Substrate size: 600 mm (moving direction) x 400
mm (width), thickness 3 mm, substrate moving speed: 20 mm / min, target: Ti with a purity of 99.9% or more, 5 inches (substrate moving direction) x 20 inches (substrate width direction), thickness 3 mm, mask member : SUS304, 700mm (board moving direction)
Two 600 mm (width direction) plates placed 150 mm apart, mask member opening: 150 mm (substrate moving direction) distance between mask member and substrate surface: 2 mm, distance between target and substrate surface: 95 mm, reached Pressure: 1 × 10 ⁻⁷ Torr, substrate temperature: 300 ° C., Ar flow rate: 47 sccm, pre-sputtering condition: 0.5 Pa, 10 minutes, reaction gas: B ₂ H ₆ , reaction gas flow rate: 4 sccm, high frequency power: 2. 5kW, Sputtering time: 30 minutes

For comparison, a thin film was formed under the same conditions as above, except that the mask means 63 was removed from the apparatus shown in FIG.

A titanium boride thin film formed using an apparatus having mask means according to the present invention has a thickness of 600.
The thickness was nm, and no compositional change in the thickness direction was observed, and the composition was substantially composed of polycrystalline TiB ₂ . And the crystallinity was good. On the other hand, in the thin film formed by using the apparatus having no mask means, a large composition variation in the thickness direction was recognized. Specifically, fine polycrystalline T
A structure similar to the laminated structure of a thin layer of iB _{2 and} a thin layer of hydrogenated amorphous boron was recognized. In such a structure, TiB
_{2 The} original characteristics cannot be obtained. A comparison of both thin films is shown below.

Composition (B / Ti) It was measured by the fluorescent X-ray method. Inventive Example: 2.02 Comparative Example: 2.43

The average crystal grain size was calculated from the (001) plane peak according to Scherrer's formula. Inventive Example: 520 nm Comparative Example: 70 nm

Vickers Hardness Inventive Example: 3300 Comparative Example: 1100

As described above, the thin film produced by the present invention has a substantially stoichiometric composition and a large average crystal grain size.
High hardness. On the other hand, the thin film of the comparative example produced by an apparatus not provided with a mask means has a significant composition shift, fine crystal grains, and low hardness.

Example 4 A titanium carbide thin film was formed by the procedure described above using the reactive vapor deposition apparatus shown in FIG. The film formation was performed under the following conditions.

Substrate: 600 mm (moving direction) x 400 mm
(Width), thickness 3 mm, moving speed 60 mm / min, vapor deposition source: Ti with purity of 99.9% or more, 40 cc capacity x 3 are juxtaposed in the substrate width direction, mask member: SUS304, 700 mm (substrate moving direction)
2 plates of × 600mm (width direction), the angle θ in Fig. 3 is 4
Installed with a gap of 5 °, distance between mask member and substrate surface: 2 mm, distance between deposition source and substrate surface: 1000 mm, reaction gas: C ₂ H ₂ , partial pressure 0.1 Pa, flow rate 10 sccm , Ionization: -250 V applied to discharge electrode, 4 A current, substrate potential: -2 kV, film formation rate: 100 nm / min,

For comparison, a thin film was formed under the same conditions as above except that the mask means 63 was removed from the device shown in FIG.

The titanium carbide thin film formed by using the apparatus having the mask means according to the present invention has a thickness of 1 μm, no composition variation in the thickness direction is observed, and the titanium carbide thin film is substantially composed of polycrystalline TiC. It had been. And the crystallinity was good. On the other hand, in the thin film formed by using the apparatus having no mask means, a large composition variation in the thickness direction was recognized. Specifically, a structure close to a laminated structure of a thin layer of fine polycrystalline TiC and a thin layer of hydrogenated amorphous carbon was recognized. With such a structure, the original characteristics of TiC cannot be obtained. A comparison of both thin films is shown below.

Composition (Ti / C) It was measured by a fluorescent X-ray method. Inventive Example: 0.99 Comparative Example: 0.71

The average crystal grain size was calculated from the (200) plane peak by the Scherrer's formula. Inventive Example: 800 nm Comparative Example: 120 nm

Vickers hardness Example of the present invention: 3000 Comparative example: 800

As described above, the thin film produced by the present invention has a substantially stoichiometric composition and a large average crystal grain size.
High hardness. On the other hand, the thin film of the comparative example produced by an apparatus not provided with a mask means has a significant composition shift, fine crystal grains, and low hardness.

The effects of the present invention are apparent from the above examples.

[Brief description of drawings]

FIG. 1 is an end view showing a configuration example of a reactive sputtering apparatus of the present invention.

FIG. 2 is an end view showing a configuration example of a reactive sputtering apparatus of the present invention.

FIG. 3 is an end view showing a configuration example of a reactive vapor deposition device of the present invention.

FIG. 4 is an X-ray diffraction chart of a Ni / TiC multilayer film after heat treatment.

FIG. 5 is an end view showing a configuration example of a conventional reactive sputtering apparatus.

FIG. 6 is an end view showing a configuration example of a conventional reactive sputtering apparatus.

FIG. 7 is a target 51- of the reactive sputtering apparatus of FIG.
FIG. 6 is a schematic diagram showing a region where plasma and reactive gas active species exist between the substrate holders 53.

FIG. 8 is a plan view showing a configuration example of mask means.

FIG. 9 is a plan view for explaining the dimensions of the opening of the mask means.

[Explanation of symbols]

 1 Substrate 50 Vacuum Chamber 51, 52 Target 53 Substrate Holder 54 Rotating Shutter 55 Changeover Switch 56 Matching Circuit 57 High Frequency Power Supply 58 High Vacuum Exhaust System 59, 60 Mass Flow Controller 61 Slide Shutter 62 Conductance Adjustment Valve 63 Mask Means 71 Deposition Source 72 Discharge Electrode 74 Shutter 77 Electron Gun Power Supply 78 Electron Gun 79 Ion Acceleration Power Supply

Claims (10)

[Claims] 1. A substrate holder that holds a plurality of substrates on its surface during sputtering is rotated so that each substrate surface periodically faces a target, and the surfaces of the plurality of substrates are placed in the vicinity of the substrate holder surface. Has masking means for covering,
A reactive sputtering apparatus in which the mask means has an opening near a position facing the target. 2. The reactive sputtering apparatus according to claim 1, wherein the diameter of the opening of the mask means is not less than the substrate diameter and not more than twice the target diameter. 3. A structure in which a substrate is moved in parallel so as to pass a position facing a target during sputtering, and a mask means for covering the surface of the substrate is provided in the vicinity of the surface of the substrate. The mask means faces the target. Reactive sputtering equipment with an opening in the vicinity. 4. The mask means opening diameter in the substrate moving direction is
4. The reactive sputtering apparatus according to claim 3, wherein the target length is equal to or more than the target length in the substrate moving direction and is equal to or less than twice the target length. 5. The distance between the substrate surface and the mask means is 0.1.
The reactive sputtering apparatus according to any one of claims 1 to 4, wherein the reactive sputtering apparatus has a thickness of -30 mm. 6. The reactive sputtering apparatus according to claim 1, wherein a reactive gas capable of depositing active species as a solid on the substrate is used, and the reactive gas is activated on the surface of the substrate by covering with a mask means. A reactive sputtering method in which the deposition of seeds is suppressed and a sputtered film is formed on the substrate surface in the vicinity of the opening of the mask means. 7. A structure in which a substrate moves parallel to a position facing a deposition source during deposition, and mask means for covering the surface of the substrate is provided near the surface of the substrate. The mask means is provided near the position facing the deposition source. A reactive vapor deposition device having an opening. 8. A cross section when the mask means is cut along a plane including the substrate moving direction, the center of the opening of the mask means, and the vapor deposition source, and connects both edges of the opening of the mask means and the center of the surface of the vapor deposition source, respectively. The reactive vapor deposition device according to claim 7, wherein the angle between the two straight lines is 90 ° or less. 9. The distance between the substrate surface and the mask means is 0.1.
The reactive vapor deposition device according to claim 7 or 8, which has a thickness of -30 mm. 10. The reactive vapor deposition apparatus according to claim 7, wherein a reactive gas capable of depositing active species as a solid on the substrate is used, and the reactive gas is activated on the surface of the substrate by covering with a mask means. A reactive vapor deposition method for suppressing deposition of seeds and forming a vapor deposition film on a substrate surface in the vicinity of an opening of a mask means.