JPH08100251A - Boron nitride-containing film coated substrate - Google Patents

Abstract

PURPOSE: To obtain a BN-contg. film coated substrate having high hardness and high toughness and excellent in stability and adhesion by laminating an inner film in which the ratio of B to N is relatively high, an outer film in which the ratio of B to N is low and a middle film in which the ratio of B to N is medium on a substrate. CONSTITUTION: The top of a substrate S is coated with an inner film S1, an outer film S3 and one or more middle films S2 as plural BN-contg. films S10 to obtain the objective BN-contg. film coated substrate. The ratio of B to N in the inner film S1 is 4-70 and the film S1 has an IR absorption peak of its IR absorption spectrum at 1,080cm<-1> or a lower peak at 1,380cm<-1> and a higher peak at 1,080cm<-1> . The ratio of B to N in the outer film S3 is <=3 and the film S3 has IR absorption peaks at 1,380cm<-1> and 780cm<-1> . The ratio of B to N in the middle films S2 is between the ratio of B to N in the inner film S1 and that in the outer film S3 and the films S2 have IR absorption peaks at 1,380cm<-1> and 1,080cm<-1> .

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to wear resistance, lubricity, moderate slidability, releasability and heat resistance of cutting tools, dies, optical element molding dies, magnetic heads and various sliding parts. The present invention relates to a substrate of an article which is required to have one or more properties, etc., and which is coated with a boron nitride-containing film capable of improving these performances and having good adhesion to the substrate.

[0002]

2. Description of the Related Art Boron nitride (BN) is roughly classified according to its crystal structure into cubic zinc blende type (c-BN) and hexagonal graphite-like structure (h-BN). To be done. The characteristics of h-BN are similar to those of graphite, and because they have a cleavage property in the C-axis direction, they are soft but excellent in slidability. Currently, artificially synthesized powdery substances are used as solid lubricants. It is widely used to reduce the friction coefficient of various sliding members.

Since c-BN has the second highest hardness after diamond and is excellent in thermal and chemical stability, it is applied to cutting tools and other fields requiring wear resistance. In addition, it is used as a material for heat sinks by taking advantage of its characteristics of insulation and high thermal conductivity. h
-BN is easily synthesized in powder form at low temperature, and is also easily synthesized in film form by various physical vapor deposition (PVD) methods or chemical vapor deposition (CVD) methods.

However, since c-BN has been artificially synthesized so far under high temperature and high pressure, the manufacturing cost thereof is very high, and the synthesized form is powdery or granular. Therefore, its application range was limited.
Therefore, various PVD methods and CVD methods have been tried to synthesize thin films of c-BN. As an example, an attempt to form a BN-containing film using a thermal CVD method will be described. A gas containing a boron (B) element and a gas containing a nitrogen (N) element or both of these elements are used as raw material gases in a reaction chamber in which a substrate is placed. It has been attempted to thermally decompose the raw material gas by introducing a gas containing the like and heating it to a temperature close to 1000 ° C. to form a BN-containing film on the substrate by the decomposition product. The -BN-containing film was easily formed, but the c-BN-containing film was difficult to form.

In this method, the substrate is required to have heat resistance, so that the material of the substrate on which the film can be formed is limited. For example, it is not possible to use, as a substrate, a material such as high speed tool steel (high speed steel) that deteriorates in hardness at a certain temperature or higher, or a mold that does not allow dimensional accuracy deviation due to deformation at high temperature. In the PVD method, for example, a target made of boron is sputtered in a nitrogen (N ₂ ) gas atmosphere,
A method such as reactive sputtering was attempted to form a BN-containing film on the surface of the opposing substrate, but the h-BN-containing film was formed, but the c-BN-containing film was not formed.

In recent years, using ions and plasma, c
-Attempts have been made to synthesize thin films of BN. For example, heat C
A c-BN-containing film has come to be formed at a lower temperature than the VD method. However, the film formed by the plasma CVD method tends to have inferior adhesion to the substrate as compared with the film formed at a high temperature.

According to Japanese Patent Publication No. 2-59863, for example, vapor deposition of a B element-containing substance and irradiation of N element-containing ions are used in combination, and this vapor deposition and ion irradiation are performed in a gas atmosphere containing N element and the irradiation is performed. By appropriately adjusting the acceleration energy of ions, the c-BN-containing film is formed on the substrate with good adhesion at a low temperature.

[0008]

However, although the c-BN film is formed on the substrate at a low temperature by this method, the c-BN film has a high hardness but is brittle. The substrate coated with the film is liable to crack in the course of use, the film is partially chipped, and various properties such as abrasion resistance of the substrate coated with the BN-containing film are not sufficiently exerted, so that the substrate is practically used. The reality is that it is difficult to serve.

As described above, a BN-containing film having practically sufficient hardness, toughness, and adhesion to a substrate has not been obtained yet. Therefore, an object of the present invention is to provide a substrate coated with a boron nitride-containing film having high hardness, excellent toughness, excellent chemical stability, and good adhesion to the substrate.

[0010]

Means for Solving the Problems The inventors of the present invention have conducted research to solve the above problems and found the following facts. As described above, BN has c-BN and h due to its crystal structure.
-It is roughly classified into BN and the like. Although c-BN has high hardness and excellent chemical stability, it has a large degree of brittleness and h-BN.
Has excellent chemical stability, but has cleavability and is soft.
Therefore, by mixing c-BN and h-BN in the film, the brittleness of c-BN is mitigated by the cleavability of h-BN, and the film as a whole has high hardness and excellent toughness. It becomes a film that has.

However, c-BN and h- contained in the film
Although it is necessary to appropriately adjust the ratio of the amount of BN, this adjustment can be performed by measuring the infrared absorption spectrum. That is, when performing a spectrum measurement by infrared absorption spectroscopy, c-BN has a major absorption peak at a wave number of 1080 cm ^-1, h-BN is 1380 cm ^-1 and 780
Since it has a major absorption peak at a wave number of cm ^−1, the absorption peak wave number and peak intensity obtained from the infrared absorption spectrum of the BN-containing film are c-BN and h-B contained in the film.
It is an index showing the ratio of N.

Further, in order for the film in which c-BN and h-BN are mixed to exhibit excellent characteristics, the ratio of the number of B atoms and the number of N atoms (B / N composition ratio) contained in the film is appropriately adjusted. There is a need to. For example, if the B / N composition ratio on the surface of the film is too large, it becomes chemically unstable, and B in the vicinity of the interface between the film and the substrate.
If the / N composition ratio is too small, the wettability to the substrate is poor,
The adhesion to the substrate is poor.

Based on the above findings, the substrate coated with a boron nitride-containing film of the present invention comprises an innermost boron nitride-containing film near the substrate, an outermost boron nitride-containing film, and one or more boron nitride-containing intermediate films between the two films. In the substrate coated with a plurality of boron nitride-containing films, the innermost formed film has a ratio of the number of boron (B) atoms to the number of nitrogen (N) atoms (B / N
In composition ratio) is 4 or more 70 or less, and, of major IR absorption peaks in the infrared absorption spectrum is detected only at a wavenumber of 1080 cm ^-1, or 1380 cm ^-1 and 108
Is detected at a wavenumber of 0 cm ^-1, the peak intensity of the wave number of 1080 cm ^-1 is greater film than the peak intensity at a wavenumber of 1380 cm ^-1, the outermost to form the film B / N composition ratio is 3 or less , And the main infrared absorption peak is 1380
a film that is detected only at a wavenumber of cm ^-1 and 780 cm ^-1, the boron nitride-containing intermediate layer is a B / N composition ratio the outermost to form the film B / N composition ratio or more, the most It is less than the B / N composition ratio of the film formed inside, and
Major infrared absorption peaks are 1380 cm ^-1 and 1080 cm
^The film is characterized by being detected at a wave number of ^-1 .

If the B / N composition ratio in the innermost film (hereinafter referred to as "inner film") is less than 4, the wettability of the film with the substrate is poor, and the film and thus the BN-containing film as a whole. The adhesion to the substrate is poor. Further, if the B / N composition ratio of the inner film is larger than 70, the ratio of BN contained in the film becomes too small, so that the film becomes chemically unstable.

The inner membrane also has the above infrared absorption peak and
And the peak intensity condition, the crystal structure of BN is mainly c
-Including BN, or mainly both c-BN and h-BN
In the infrared absorption spectrum
1080 cm by c-BN ^-1The wave intensity peak intensity is h
-By BN 1380cm^-1Greater than the peak intensity of the wave number of
It is included in a ratio that makes you feel better. C- in the inner membrane
It contains almost no BN or the film is c-BN and h
-When BN is included, the ratio of the two is the above ratio.
If not, the hardness of the film is low, and
The hardness of the entire BN-containing film becomes low.

When the B / N composition ratio in the outermost film (hereinafter referred to as "outer film") is larger than 3, the proportion of BN contained in the film is small and the chemical stability of the film is low. Not enough. Further, the outer film is mainly composed of h-BN as a crystal structure of BN from the condition of the infrared absorption peak.
However, when h-BN is scarcely contained in the film, the toughness of the film and the entire BN-containing film are poor.

The interlayer film is mainly composed of c-BN and h-BN as the crystal structure of BN because of the above infrared absorption peak conditions.
including. As described above, the intermediate film has an intermediate B / N composition ratio between the inner film and the outer film and a crystal structure of BN, thereby alleviating an extreme mismatch between the inner film and the outer film. However, it is possible to improve the adhesion between the BN-containing films, and thus the adhesion of the entire BN-containing film to the substrate.

Further, when two or more intermediate films are formed, it is desirable that the B / N composition ratio of each intermediate film be gradually decreased from the inner film to the outer film.
The crystal structure of N is c in order from the inner film to the outer film.
It is desirable that the proportion occupied by -BN is reduced and the proportion occupied by h-BN is increased. This makes it possible to reduce the difference in composition between the intermediate films, and improve the adhesiveness between the intermediate films, and thus the adhesiveness between the BN-containing film as a whole and the substrate.

The following methods are conceivable as a method for manufacturing the base body. . That is, the substrate is supported by a holder in a vacuum chamber for film formation, and the B element-containing substance is vacuum-deposited and / or sputter-deposited on the substrate at the same time, alternately or after the vapor deposition, ions are irradiated from an ion source. BN
A containing film is formed on the substrate. According to this ion vapor deposition thin film forming method, it is possible to form a film at a low temperature, so that there is an advantage that the material of the substrate can be selected from a wide range in terms of heat resistance.

Examples of the B element-containing substance used in the above method include boron compounds, such as boron compounds, such as boron oxide, boron nitride, boron carbide, boron sulfide, phosphorus boride, hydrogen boride and various metal borides. It is possible to use one or more of these. The ions used in the above method act on the evaporated B atoms to form B atoms.
Any material that forms an N-containing film may be used, and examples thereof include N atom ions, N molecule ions, and ammonia ions (NH ₃ ⁺ ).
And the like, and one or more of these are used. Further, when forming the inner film and the intermediate film, it is possible to mix ions such as those containing N element with inert gas ions such as argon ions (Ar ⁺ ) and hydrogen ions (H ⁺ ). Evaporated B atoms can be more highly excited, which is advantageous for the formation of c-BN.

Crystal structure and B of BN formed in each film
The / N composition ratio is controlled by appropriately combining conditions such as the ratio of the number of B atoms and the number of N atoms reaching the substrate (B / N transport ratio), the ion species, and the acceleration energy of irradiation ions. The B / N transport ratio is controlled, for example, by monitoring the deposition amount on the substrate using a film thickness monitor such as a crystal oscillator type film thickness monitor, and by measuring the amount of ions on the substrate using an ion current measuring device such as a Faraday cup. This can be done by monitoring the irradiation dose.

The acceleration energy of irradiation ions is 0.1 keV.
As described above, the voltage is preferably 40 keV or less. 0.1k
If it is smaller than eV, it becomes difficult to form c-BN and 40k
If it is larger than eV, the number of defects in the film increases, and the hardness of the film decreases and the chemical stability decreases. The ion acceleration energy may be constant, preferably within the above range, or may be continuously or intermittently changed.

The angle of incidence of ions on the substrate is not particularly limited, and film formation may be performed while rotating the substrate. The ion source system is also not particularly limited, for example, Kaufman type,
A bucket type or the like can be considered. Further, for a substrate for which thermal damage must be sufficiently avoided, it is preferable to perform film formation while cooling the substrate by cooling the substrate holder.

The material of the substrate is not particularly limited, and for example, various ceramics, metals, polymers, etc. can be considered. In addition to the above-mentioned ion vapor deposition thin film forming method, the substrate of the present invention includes various PVD methods such as an ion plating method and various C
It can be manufactured by the VD method or the like.

[0025]

According to the BN-containing film-coated substrate of the present invention, the substrate is coated with an inner film containing BN, an outer film, and at least one intermediate film therebetween. The inner film mainly contains high hardness c-BN as a crystal structure of BN, or mainly contains c-B.
It contains both N and cleavable and soft h-BN, both of which in the infrared absorption spectrum are due to c-BN.
The peak intensity of the wave number of 0 cm ^-1 is 1380 by h-BN.
It is included in such a ratio that it becomes larger than the peak intensity of the wave number of cm ⁻¹ . When the film mainly contains c-BN, the film has high hardness, and the film mainly contains h-BN and c-BN.
When BN is included in the above ratio, the brittleness of c-BN is relaxed by the cleavability of h-BN, so that the film has high hardness and appropriate toughness. In any case, the film, and thus the entire BN-containing film, has high hardness.

The B / N composition ratio of the inner film is 4 or more and 7
B contained in the film due to its relatively large value of 0 or less
Since the ratio of N is small within a range that does not extremely reduce the chemical stability of the film, the film has good wettability with the substrate, and the film, and thus the entire BN-containing film, has good adhesion to the substrate. Become. The outer film mainly has a BN crystal structure,
Since it contains cleavable and soft h-BN, the toughness of the film, and by extension, the BN-containing film as a whole, is excellent.

Further, since the B / N composition ratio of the outer film is as small as 3 or less, the proportion of BN contained in the film is large, and the chemical stability of the film and the entire BN-containing film is excellent. Further, at least one intermediate film is formed between the inner film and the outer film, and the intermediate film mainly contains c-BN and h-BN as a crystal structure of BN and has a B / N composition ratio of the above. It takes an intermediate value between the inner membrane and the outer membrane. Thus, since the intermediate film has an intermediate composition between the inner film and the outer film, the film alleviates an extreme mismatch between the inner film and the outer film, and contains each BN. The adhesion between the films, and by extension, the adhesion of the entire BN-containing film to the substrate is improved. Also, c-B
The brittleness of N is relaxed by the cleavability of h-BN,
The film has a high hardness and an appropriate toughness.

As a result, the BN-containing film as a whole has high hardness, excellent toughness, excellent chemical stability, and good adhesion to the substrate.

[0029]

Embodiments of the present invention will be described below with reference to the drawings. 1 is an enlarged cross-sectional view of a part of a substrate according to one embodiment of the present invention, FIG. 2 is an enlarged cross-sectional view of a part of a substrate according to another embodiment of the present invention, and FIG. 3 shows a schematic configuration of a film forming apparatus used for manufacturing the substrate shown in FIG.

This apparatus has a vacuum container 1 in which a substrate holder 2 for supporting a substrate S is installed.
The evaporation source 3 and the ion source 4 are installed at positions facing each other. In the vicinity of the substrate S, a film thickness monitor 5, here, a crystal oscillator type film thickness monitor, and an ion current measuring device 6, here, a Faraday cup are installed. Further, an exhaust device 7 is attached to the container 1 so that the inside of the container 1 can have a predetermined degree of vacuum.

In manufacturing the substrate of the present invention, first, the substrate S is supported by the holder 2 and then the inside of the vacuum container 1 is set to a predetermined vacuum degree. Next, using the evaporation source 3 for the substrate S,
The element-containing substance 3a is vacuum-deposited by means of electron beam, laser, high frequency or the like. Instead of vacuum vapor deposition, the B element-containing substance 3a may be sputtered by a means such as an ion beam, magnetron, or high frequency to form a film on the substrate S.

Simultaneously with, or alternately with, the vapor deposition of the B element-containing substance 3a, or after the vapor deposition, the vapor deposition surface is irradiated with ions 4a such as ions containing the N element from the ion source 4. By performing the film forming operation described above three times and appropriately combining the conditions of the B / N transport ratio, the ion species, and the acceleration energy of irradiation ions for each operation, as shown in FIG. 1, the inner film is formed on the substrate S. A BN-containing film S10 is formed by stacking S1, the intermediate film S2, and the outer film S3 in this order.

The intimal S1 is at B / N composition ratio is 4 or more 70 or less, and, of major infrared absorption peak is detected only at a wavenumber of 1080 cm ^-1, or 1380 cm ^-1 and 108
Is detected at a wavenumber of 0 cm ^-1, the peak intensity of the wave number of 1080 cm ^-1 is greater film than the peak intensity at a wavenumber of 1380 cm ^-1. The outer film S3 has a B / N composition ratio of 3 or less, and has major infrared absorption peaks of 1380 cm ^-1 and 780c.
It is a film that can be detected only at a wave number of m ^-1 . The intermediate film S2 is B
/ N composition ratio is not less than the B / N composition ratio of the outer film S3 and not more than the B / N composition ratio of the inner film S1, and the main infrared absorption peaks are at wave numbers of 1380 cm ^-1 and 1080 cm ^-1 . Membrane to be detected.

As a result, the inner film S1 has a high hardness, an appropriate toughness in some cases, and an excellent adhesion to the substrate S.
Further, the outer film S3 is excellent in toughness and chemical stability. Further, the intermediate film S2 alleviates the compositional mismatch between the inner film S1 and the outer film S3, improves the adhesion of the films S1, S2, S3, and has high hardness and excellent toughness. Therefore the membrane S
The BN-containing film S10 composed of 1, S2, and S3 has high hardness, excellent toughness and chemical stability as a whole, and good adhesion to the substrate S.

The film forming operation is carried out four times, and the B / N transport ratio, the ion species, and the acceleration energy of the irradiation ions are appropriately combined for each operation so that the inside of the substrate S can be formed as shown in FIG. A B / N-containing film S100 is formed by laminating the film S1, the intermediate film S21, and the outer film S3 in this order. The intermediate film S21 has the film S21b formed outside the film S21a.

[0036] the film S1 is at B / N composition ratio is 4 or more 70 or less, and, of major infrared absorption peak is detected only at a wavenumber of 1080 cm ^-1, or 1380 cm ^-1 and 108
Is detected at a wavenumber of 0 cm ^-1, the peak intensity of the wave number of 1080 cm ^-1 is greater film than the peak intensity at a wavenumber of 1380 cm ^-1. The outer film S3 has a B / N composition ratio of 3 or less, and has major infrared absorption peaks of 1380 cm ^-1 and 780c.
It is a film that can be detected only at a wave number of m ^-1 . The film S21a and the film S21b each have a B / N composition ratio of not less than the B / N composition ratio of the outer film S3 and not more than the B / N composition ratio of the inner film S1 and having a main infrared absorption peak of 1380 cm. ^-1 and a film detected at a wave number of 1080 cm ^-1 .

The inner film S21a of the intermediate film 21 is
Large B / N composition ratio than the outer layer S21b, also the peak intensity of the wave number of the wave number of the peak intensity and 1380 cm ^-1 in 1080 cm ^-1 in the infrared absorption spectrum magnitude of the ratio (1080 cm ^-1 peak intensity / 1380 cm ^{- 1} peak intensity) is larger than the outer film S21b. Thereby, the films S1, S21a, S21 forming the BN-containing film S100 are formed.
Since the difference in composition between b and S3 is small, each film S1,
The adhesiveness between S21a, S21b, and S3 becomes better, and by extension, the adhesiveness between the film S100 and the substrate S becomes better.

Next, a specific example of the production of the substrate of the present invention by the film forming apparatus shown in FIG. 3 and the substrate coated with the BN-containing film obtained thereby will be described. Experimental Example 1 Using the apparatus shown in FIG. 2, silicon (plane orientation (10
0)) The substrate S was placed on the substrate holder 2 and the inside of the vacuum container 1 was set to a vacuum degree of 5 × 10 ⁻⁷ Torr. Then purity 9
A 9.7% boron pellet 3a was vaporized using the electron beam evaporation source 3 to form a film on the substrate S. At the same time, nitrogen (N ₂ ) having a purity of 5N (99.999%) is supplied to the ion source 4.
Gas is introduced until the inside of the vacuum chamber 1 reaches 5 × 10 ⁻⁵ Torr and ionized, and the ions 4a are applied to the substrate S with an acceleration energy of 15 keV at an angle of 0 ° with respect to the normal to the substrate S. Irradiated. As the ion source, a bucket type ion source using a cup magnetic field was used.

In the film forming operation, the B / N transport ratio is adjusted so that the B / N composition ratio is 40 in consideration of the sputtering efficiency of boron atoms by nitrogen ions and the like. The inner film S1 was formed. Then, the B / N transport ratio is adjusted so that the B / N composition ratio becomes 20, and otherwise the film thickness of about 5 is formed on the inner film S1 under the same conditions as the formation of the inner film S1.
An intermediate film S2 having a thickness of 00 nm was formed.

Further, B is adjusted so that the B / N composition ratio becomes 1.5.
The / N transport ratio is adjusted, and otherwise the outer film S3 having a thickness of about 300 nm is formed on the intermediate film S2 under the same conditions as the formation of the inner film S1.
Was formed. Experimental Example 2 An inner film S1 having a B / N composition ratio of 40 and a film thickness of about 500 nm was formed on a silicon (plane orientation (100)) substrate S by the same film forming operation as that for forming the inner film S1 of Experimental Example 1. , An intermediate film S21a having a B / N composition ratio of 20 and a film thickness of about 500 nm, and an intermediate film S21b having a B / N composition ratio of 10 and a film thickness of about 500 nm, B / N
An outer film S3 having a composition ratio of 1 and a film thickness of about 300 nm was formed.
The acceleration energy of all the ions 4a was 10 keV. Other conditions were the same as in the formation of the inner film S1 in Experimental Example 1. Comparative Example 1 By the same film forming operation as in the formation of the inner film S1 in Experimental Example 1, the acceleration energy of the ions 4a was set to 10 keV, and the B / N composition ratio was 2 on the silicon (plane orientation (100)) substrate S. To form a BN-containing film with a thickness of about 500 nm,
A BN-containing film having a / N composition ratio of 1 and a film thickness of about 500 nm was formed. Other conditions were the same as in the formation of the inner film S1 in Experimental Example 1. Comparative Example 2 By the same film formation operation as in the formation of the inner film S1 of Experimental Example 1, the acceleration energy of the ions 4a was set to 10 keV, and the B / N composition ratio was 20 on the silicon (plane orientation (100)) substrate S.
Thus, a BN-containing film having a film thickness of about 500 nm was formed. Other conditions were the same as in the formation of the inner film S1 in Experimental Example 1. Comparative Example 3 By the same film forming operation as in the formation of the inner film S1 in Experimental Example 1, the acceleration energy of the ions 4a was set to 10 keV, and the B / N composition ratio was 1 on the silicon (plane orientation (100)) substrate S. Thus, a BN-containing film having a film thickness of about 500 nm was formed. Other conditions were the same as in the formation of the inner film S1 in Experimental Example 1.

Table 1 shows the experimental examples 1 and 2 and the comparative example 1,
The B / N composition ratio and the film thickness of the films formed in 2 and 3 are shown together.

[0042]

[Table 1]

Next, the infrared absorption spectra of the films formed in Experimental Examples 1 and 2 and the film formed in Comparative Example 2 by Fourier transform infrared absorption spectroscopy (FT-IR) were measured using silicon ( The surface orientation (100) was measured using the substrate S as a reference. The wave numbers of the infrared absorption peaks detected are summarized in Table 2. The crystal structure of BN, which is considered to be contained in each film based on the detected peak wave number, is also shown.

[0044]

[Table 2]

The films of Comparative Examples 1 and 3 were peeled off immediately after the film formation, and the above infrared absorption spectrum measurement could not be performed. It is considered that this is partly because the film-coated substrates according to Comparative Examples 1 and 3 had a film having a relatively small B / N composition ratio formed directly on the substrate. It is considered that the film had bad properties and was easily peeled off.

Next, the hardness of the film-coated substrates according to Experimental Examples 1 and 2 and Comparative Example 2 was measured with a 10 g micro Vickers hardness meter. The results are shown in Table 3.

[0047]

[Table 3]

The film-coated substrates of Experimental Example 1 and Experimental Example 2 had higher hardness than the film-coated substrate of Comparative Example 2. This corresponds to the film S10 according to Experimental Example 1 and the film S1 according to Experimental Example 2.
It is considered that 00 has the inner film S1 made of high hardness c-B / N. Further, it can be seen that in any film-coated substrate, cracks do not occur at the tip of the indentation during hardness measurement, and the film toughness is good. This corresponds to the film S10 according to the experimental example 1 and the experimental example 2
In the film S100 according to (1), the h-
It is considered that this is due to having the outer membrane S3 composed of B / N.

Next, the film-coated substrates according to Experimental Examples 1 and 2 and Comparative Example 2 were heated in the atmosphere and the temperature at which the film was oxidized and the weight changed was examined. Although the weight changed up to 700 ° C., the weight of the film-coated substrate according to Comparative Example 2 changed at 300 ° C. It can be seen that the film-coated substrates according to Experimental Examples 1 and 2 are chemically more stable than the film-coated substrate according to Comparative Example 2. It is considered that this is because the both film-coated substrates have the outer film S3 having a small B / N composition ratio.

As described above, the film-coated substrates according to Experimental Examples 1 and 2 have better film adhesion than the film-coated substrates according to Comparative Examples 1 and 3 and have higher hardness than the film-coated substrates according to Comparative Example 2. It can be seen that the film is chemically stable and the toughness of the film is good.

[0051]

According to the present invention, it is possible to provide a substrate coated with a boron nitride-containing film having high hardness, excellent toughness, excellent chemical stability and good adhesion to the substrate. . More specifically, the boron-nitride-containing film-coated substrate of the present invention can prevent the film from being partially broken or cracked due to its excellent toughness even under a harsh environment or a harsh use condition. In addition to this, the high hardness provides excellent wear resistance, and the excellent chemical stability allows the film to be formed with sufficient adhesion for practical use without changing the film quality even at high temperatures. Therefore, it can be used without impairing the above-mentioned various characteristics.

[Brief description of drawings]

FIG. 1 is a partial enlarged cross-sectional view of an embodiment of the present invention.

FIG. 2 is a partial enlarged cross-sectional view of another embodiment of the present invention.

FIG. 3 is a diagram showing a schematic configuration of a film forming apparatus used for manufacturing the substrate shown in FIGS. 1 and 2.

[Explanation of symbols]

 1 vacuum container 2 substrate holder 3 evaporation source 3a vapor deposition material 4 ion source 4a ion 5 film thickness monitor 6 ion current measuring instrument 7 exhaust device S substrate S1 inner film S2, S21a, S21b intermediate film S21 intermediate film S21a, S21b S3 Outer film S10 Film composed of films S1, S2 and S3 S100 Film composed of films S1, S21 and S3

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Kiyoshi Ogata 47 Umezu Takaunecho, Ukyo-ku, Kyoto City Nissin Electric Co., Ltd.

Claims (1)

[Claims] 1. A boron nitride containing innermost layer close to the substrate
The membrane, the outermost boron nitride containing membrane and one or more between the membranes.
With multiple boron nitride-containing films, including boron nitride-containing intermediate films
A coated substrate, said innermost film being formed
Is the ratio of the number of boron (B) atoms to the number of nitrogen (N) atoms (B / N
Composition ratio) of 4 or more and 70 or less, and infrared absorption spectrum
Infrared absorption peak at 1080 cm^-1Wave of
Only detected by number or 1380 cm ^-1And 108
0 cm^-1Detected at the wave number of 1080 cm^-1Wave number of
Strength of 1380 cm^-1Greater than the peak intensity of the wave number of
The outermost film is a B / N composition.
The ratio is 3 or less, and the main infrared absorption peak is 1380
cm^-1And 780 cm^-1Is a film that can be detected only at
The B / N composition ratio of the boron nitride-containing intermediate film is
The B / N composition ratio of the film formed on the outer side or more,
It is less than the B / N composition ratio of the film formed inside, and
The main infrared absorption peak is 1380 cm^-1And 1080 cm
^-1Nitride film, which is a film that can be detected at different wave numbers
Arsenic-containing film-coated substrate.