JPH1073705A - Reflector - Google Patents

Abstract

(57) [Summary] An inexpensive reflector having high reflectance characteristics and high heat resistance, and excellent heat dissipation. A reflective surface is formed on a surface of a thin film or a laminate by forming a thin film or a laminate on one surface of a base. Base 1 in which base 11 is made of a metal material
A glass layer 12 is formed on the AlN layer 11b, and a thin film 13 or a laminate is formed on the glass layer 12. The thin film 13 is preferably an Au thin film, an Ag thin film, or an Al thin film, and may be a stacked body formed by alternately stacking a high refractive index layer and a low refractive index layer a plurality of times. The glass layer 12 is preferably formed to a thickness of 0.1 μm to 100 μm, and the base 11a is preferably made of W, Al, Cu, or an alloy thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a reflector suitable for reflecting various light rays. More specifically, the present invention relates to a reflector suitable for reflecting an energy beam such as an infrared ray or a laser beam.

[0002]

2. Description of the Related Art Conventionally, as a reflecting mirror used in a solar energy absorbing device, a metal reflection made of aluminum, silver, or the like is formed on a substrate formed of an appropriate material such as a metal such as aluminum, a steel plate, or stainless steel, an alloy, or a plastic. film is deposited, a reflecting mirror transparent inorganic protective film made of a glassy layer such as SiO ₂ is formed is disclosed in the surface of the metal reflective layer (JP-a 57-4003). Further, as an infrared reflecting mirror, a reflecting mirror in which a base is formed by extruding Al and a plating layer is formed on one surface of the base is known. In this reflector, after buffing the surface of the base, a Ni plating layer is formed on the surface, and an Au plating layer is further formed on the surface of the Ni plating layer. According to these reflectors described above, the reflective surface has a high reflectance in a wide range from the ultraviolet region to the visible region and the infrared region, and if the reflective film is protected by the transparent inorganic protective film, the reflective surface is smooth and dirty. And the reflectance does not decrease. Further, this protective film is excellent in acid resistance, alkali resistance, and salt resistance, and can maintain the reflection characteristics for a long time.

On the other hand, as a reflecting mirror for reflecting a high-energy light beam such as a laser beam, a mirror formed by forming a dielectric material on a substrate made of a suitable material such as a metal or an alloy such as aluminum or quartz glass is used. Are known. The surface of the substrate is mirror-polished, and the dielectric is formed on the substrate by a method such as an evaporation method or a sputtering method. By forming a laminate formed by alternately laminating such a high refractive index layer and a low refractive index layer a plurality of times on a substrate, a plurality of boundary surfaces can be provided. It can be increased to increase the reflection efficiency.

However, since a metal material such as aluminum has a property of causing an oxidation reaction, when used for an energy beam, the oxidation reaction is accelerated by a temperature rise caused by reflection of the beam. On the other hand, when the substrate is made of metal, the metal particles undergo grain growth. When the substrate is made of plastic, thermal deformation occurs, and various plating layers or laminates are peeled off to lower the reflectance. In such a case, it is conceivable to use quartz glass, which has good workability and excellent oxidation resistance, as the substrate, but because the thermal conductivity of quartz glass itself is low, it is also caused by the reflection of energy rays. There is a problem that the reflectance rises due to peeling of various plating layers or laminates due to a rise in temperature or thermal deformation of the substrate. In order to solve these problems, a reflector using a ceramic such as Si or SiC having a relatively high thermal conductivity for a substrate is known. By using such a substrate, a reflection mirror having high oxidation resistance and good heat resistance can be manufactured.

[0005]

However, Si is excellent in thermal conductivity, but mechanical strength is weaker than aluminum or quartz glass, so it can be used for mirror-polishing the surface and handling for forming the dielectric layer. There is a problem that it causes difficulty and cannot be used in a place where mechanical strength is required. Also,
SiC has a higher mechanical strength than Si and does not cause any trouble in Si, but has a problem that the workability in mirror polishing is inferior due to the increase in mechanical strength. That is, due to the difficulty of mirror polishing, an excessive time is required as compared with a normal processing time for processing Si or the like. There is a problem that it is difficult to finish the flatness. Furthermore, these ceramics are expensive and there is a problem that the unit price of the product itself is increased. An object of the present invention is to provide an inexpensive reflector having high reflectance characteristics and high heat resistance, and excellent in heat dissipation.

[0006]

The invention according to claim 1 is
As shown in FIGS. 1 and 2, this is an improvement of a reflecting mirror in which a reflecting surface is formed on the surface of the thin film 13 or the laminate 21 by forming the thin film 13 or the laminate 21 on one surface of the base 11. The characteristic configuration is that the base 11 includes a base 11a made of a metal material and an AlN layer 11b laminated or bonded to the base 11a directly or via a brazing material.
1b, the glass layer 12 is formed, and the thin film 13 or the laminate 21 is formed on the glass layer 12. The base 11 is composed of a base 11a made of a metal material and an AlN layer 11b.
And the AlN layer 11b has a reflective surface so as to have high heat resistance. In addition, expensive AlN
Inexpensive substrate 11 by minimizing the amount of
Can be obtained. Further, even if the surface of the substrate 11 is roughened by forming the glass layer 12 on the AlN layer 11b, the glass layer 12 smoothes the surface, and distorts the surface of the thin film 13 or the laminate 21 formed on the glass layer. The mirror surface is free from irregularities and has high reflectance characteristics.

According to a second aspect of the present invention, as shown in FIG. 1 or FIG.
u thin film, Ag thin film or Al thin film having a thickness of 0.01 μm
This is a reflecting mirror formed to a thickness of 10 μm. The Al thin film is most frequently used in a reflecting mirror, and is widely used in many optical machines and devices because it can be used in a wide wavelength range. However, in order to improve the reflectivity and durability,
Usually, it is preferable to provide a protective film of AgF ₂ or SiO ₂ on the Al thin film. The Au thin film is suitable for an infrared mirror because it has high reflectance and chemical stability from near infrared to far infrared. Although the Ag thin film has high reflectivity in a wide wavelength range from the visible region to the far infrared region, it is preferable to provide a protective film like the Al thin film because it has high reactivity and poor chemical stability. Therefore, these thin films 13
Is selected according to the use of the reflecting mirror, and the thickness of the thin film is preferably formed to a thickness of 0.2 μm to 4 μm. It is extremely difficult to form these thin films 13 to a thickness of less than 0.01 μm, and if the thickness exceeds 10 μm, it is not economical.

According to a third aspect of the present invention, as shown in FIG. 2, in the first aspect of the present invention, a laminate 21 is formed by alternately laminating a high refractive index layer 22 and a low refractive index layer 23 a plurality of times. It is a formed reflecting mirror. Since the reflection of light rays mainly occurs at the interface of the refractive index, the reflection occurring at different interfaces has almost no reflection loss due to absorption, and can be a very good reflecting surface. Therefore, normally, there is no light absorption, and the low refractive index layer 23 is chemically stable and has a low refractive index.
Chemically stable high refractive index layer 2 with relatively little light absorption
By forming 2, the reflection characteristics at the boundary surface can be improved, and by providing a plurality of such layers 23 and 22, the reflection efficiency is improved. High refractive index layer 22
And the low-refractive-index layer 23 has a thickness of 30 nm to 150 nm and 60 nm to 300 nm depending on the use of the high-energy light reflecting mirror.
It is preferable that each is formed in the thickness of. If the thicknesses of the high refractive index layer 22 and the low refractive index layer 23 are out of the above ranges, a sufficient reflectance cannot be obtained.

The laminate 2 formed on the glass layer 12
The high refractive index layer 22 and the low refractive index layer 23 are formed by a sputtering method, a vapor deposition method, or the like. Examples of the high refractive index layer 22 include ZnS (zinc sulfide), TiO ₂ (titanium dioxide), and CeO ₂ (cerium dioxide). Z
nS and TiO ₂ form a fairly hard and fairly durable film without light absorption in the visible spectrum, while CeO ₂ forms a more chemically stable film. Examples of the low refractive index layer 23 include MgF ₂ (magnesium fluoride) and ThF ₂ (thorium fluoride). Mg
Similarly, F ₂ and ThF ₂ form extremely hard and durable films without light absorption in the visible spectrum.

According to a fourth aspect of the present invention, as shown in FIGS. 1 to 3, in the invention according to any one of the first to third aspects, the reflection is performed by forming the glass layer 12 to a thickness of 0.1 μm to 100 μm. It is a mirror. The thickness of the glass layer 16 is 0.1 μ
When it is less than m, the surface smoothness of the substrate is not sufficient, and as a result, it is difficult to obtain a high reflectance. When it exceeds 100 μm, there is a problem that the thermal conductivity of the entire substrate is extremely lowered. The glass layer is preferably provided on a glass-mixed Al ₂ O ₃ layer in which glass provided on the AlN layer 11b is mixed. Although glass mixed the Al ₂ O ₃ layer may be provided directly to the AlN layer 11b, Al ₂ O ₃ in the AlN layer 11b
It is more preferable to provide them via a layer. In the reflecting mirror, the Al ₂ O ₃ layer has high consistency with the sintered body at the interface with the AlN layer 11b, which is a sintered body, and is strongly bonded to the AlN layer 11b. This Al ₂ O ₃ layer functions as a glass barrier layer for the AlN layer 11b and prevents generation of bubbles at the interface of the AlN layer 11b.

Since the Al ₂ O ₃ layer formed by thermal oxidation is porous, the following features are provided when the Al ₂ O ₃ layer is provided. That is, the coefficient of thermal expansion is (7-8) × 10 ^−6.
Since the thermal expansion coefficient of the AlN layer 11b is as small as about 4 × 10 ⁻⁶ / ° C. as compared with Al ₂ O ₃ of / ° C., glass mixed Al formed by intrusion of glass into the porous Al ₂ O ₃ layer _{The 2} O ₃ layer is
When the thermal expansion coefficient of the glass is smaller than the thermal expansion coefficient of Al ₂ O ₃ , the thermal expansion coefficient approaches the AlN layer 11b, and the thermal stress generated in the heat treatment process during layer formation can be sufficiently relaxed.
No cracks occur in the Al ₂ O ₃ layer.

Further, a glass mixed Al ₂ O ₃ layer and a glass layer 1
2, an oxide particle-dispersed glass layer in which one or more oxide particles selected from the group consisting of Al ₂ O ₃ , TiO ₂ and ZrO ₂ particles are dispersed in glass may be provided. The oxide particle-dispersed glass layer is made of Al ₂ O ₃ , TiO ₂ , Z
Since particles having better heat conductivity than glass such as rO ₂ are dispersed in the glass layer, the heat conductivity of this layer increases, and the heat dissipation characteristics of the reflector are further improved. The formation of the oxide particle-dispersed glass layer improves the surface smoothness of the glass-containing Al ₂ O ₃ layer. This means that AlN with relatively large surface roughness
This means that it is possible to improve the substrate surface smoothness by reducing the substrate surface roughness even in the layer. Therefore, the surface of the thin film 13 or the laminate 21 formed on the smoothed glass layer 12 has a mirror surface without distortion. In this case, Al
Preferably, the ₂ O ₃ layer is formed to a thickness of 0 to 9.99 μm, and the glass-mixed Al ₂ O ₃ layer is formed to a thickness of 0.01 to 10 μm.

[0013] The invention according to claim 5 is the invention according to claims 1 to 4.
In the invention according to any one of the above, the base 11a is W, A
This is a reflecting mirror made of l or Cu or an alloy thereof. As a method of directly laminating and bonding the base 11a and the AlN layer 11b, when the base 11a is formed of W, Al or Cu, a load of 0.5 to 2 kgf / cm is applied to the base 11a and the AlN layer 11b in a state where the base 11a and the AlN layer 11b are stacked. ² and heating to 1065 ° C. in a N ₂ atmosphere by the so-called DBC method (Direct
Bonding Copper method) or base 11a and AlN layer 1
There is a so-called active metal method in which a load of 0.5 to ² kgf / cm ² is applied to the Ag-Cu-Ti brazing material in a state where the foil is sandwiched between the brazing material 1b and 800-900 ° C in a vacuum.

According to a sixth aspect of the present invention, as shown in FIG. 3, in the first aspect of the present invention,
The base 11b is made of Cu, and the brazing material is made of Ag-C
The reflector is a u-Ti brazing material 31. Base 11a
Is formed of Cu, the AlN layer 11b
Is oxidized to form an Al ₂ O ₃ layer on its surface with an optimum thickness, and then the base 11a is formed by a DBC method or an active metal method.
It is preferable that the AlN layer 11b is laminated and adhered. The invention according to claim 7 is the reflector according to any one of claims 1 to 4, wherein the base 11a is formed of Al and the brazing material is an Al-Si brazing material. Base 1
When 1a is formed of Al, a load of 0.5 to 2 kgf / c is applied to the base 11a and the AlN layer 11b with the Al-Si brazing material foil sandwiched between the base 11a and the AlN layer 11b.
By adding m ² and heating to 600 to 650 ° C. in a vacuum, the AlN layer is laminated and adhered to the base.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the AlN layer 11b bonded to the base 11a of the present invention is not limited to a sintered body consisting of aluminum nitride alone, but contains aluminum nitride as a main component and various additives such as CaO. , Y ₂ O ₃ etc. may be used. The AlN layer 11b is bonded to the base 11a by laminating the base 11a to the AlN layer 11b by the DBC method or the active metal method using the brazing material 31. When the Al ₂ O ₃ layer is provided on the AlN layer 11b, the aluminum nitride sintered body is subjected to an oxygen partial pressure of 1 × 10 ⁻² atm or more and a steam partial pressure of 1 × 10 ⁻³ atm or less. In the atmosphere, 3 to 0.
It is made by heat treatment for about 5 hours. The higher the temperature, the shorter the processing time may be. By this heat treatment, the surface of the aluminum nitride sintered body is oxidized to have a porosity of 0.01.
15 volume% of Al ₂ O ₃ layer is formed.

The glass-mixed Al ₂ O ₃ layer and the glass layer 12 on the AlN layer 11b before forming the Au, Ag or Al thin film of the reflecting mirror are made of Al ₂ O ₃ formed by the thermal oxidation.
A suspension in which glass particles are dispersed in a solvent is applied on the layer, dried and fired, and the heat-treated glass is softened at a temperature at which the glass is softened so that the softened glass penetrates into the fine pores above the Al ₂ O ₃ layer. Made. When invading glass,
It is necessary not to allow the softened glass to reach the aluminum nitride sintered body. In other words, it is necessary to leave the Al ₂ O ₃ layer on the aluminum nitride sintered body. This is because bubbles are not generated at the interface of the sintered body due to the reaction between the glass and the sintered body.

The glass layer 12 preferably has a coefficient of thermal expansion close to the coefficient of thermal expansion of the AlN layer 11b, which is a substrate, because defects such as cracks do not occur when these layers are formed. Specifically, the thermal expansion coefficients of these layers are
(4.4 ± 1.0) × 10 ⁻⁶ / close to the thermal expansion coefficient of 1b
C. is preferred. Further, the glass layer 12 is formed by mixing these glass powders with a solvent to form a glass paste, and forming the glass paste on an Al ₂ O ₃ formed by thermal oxidation.
It is formed by coating on the O ₃ layer by a method such as screen printing, spray coating, dip coating, spin coating, drying, and baking.
Further, the glass layer 12 is formed by applying a glass paste to a plastic base sheet and then peeling the base sheet by stacking the paste surface of the sheet on the surface to be laminated.
It can also be formed by a gel method, a sputtering method, or the like.

A thin film 13 formed on the glass layer 12
Is a thin film formed by applying and baking a paste containing an organic compound of Au, Ag or Al. The metal contained in the thin film 13 is Au, Ag or Al or an alloy thereof, and is preferably contained in the paste in an amount of 15 to 75% by weight.
0-50% by weight is more preferred. If the content of these metals or their alloys is less than 15% by weight, it is difficult to obtain a continuous and dense thin film, and if it exceeds 75% by weight, the adhesion to the glass layer 12 will be poor. The paste of the present invention is Au, A
g or Al or an alloy thereof is not in a powder state, and a metal component and a trace amount of another metal component form a compound with an organic component,
Since it is in a liquid state, it has a feature that a continuous thin film having a thickness of 1 μm or less can be obtained. An organic substance such as α-terpineol or ethyl cellulose is added to the liquid organic compound to form a paste. The organic substance imparts viscosity to the paste to enhance coatability, and has a function as a binder after firing. Other metal components include Pb,
Bi, Si, etc. are mentioned. The thin film 13 is formed by applying an organic compound paste to the surface of the glass layer 12 by a method such as screen printing, spray coating, dip coating, or spin coating, drying, and then firing.

When the laminate 21 is formed on the glass layer 12, the high refractive index layer 22 and the low refractive index layer 23 are formed by a sputtering method, a vapor deposition method, or the like. However, the thicknesses of these layers 22 and 23 need to be selected in consideration of the intended use. That is, since the reflected light from the boundary surfaces of the layers 22 and 23 is reflected while being overlapped with each other, the light reinforces each other when the phase of the light overlaps, and the light cancels out when the phase is inverted. become. Therefore, the reflectivity can be increased by adjusting the film thickness according to the wavelength and the incident angle of the light beam to be reflected, and sequentially increasing the number of boundary surfaces by laminating a plurality of times. It is preferable that at least two layers of the high refractive index layer 22 and the low refractive index layer 23 are formed in the laminate 21. If it is less than two layers, it will be difficult to obtain a sufficient reflectance.

[0020]

Next, embodiments of the present invention will be described. Example 1 The reflecting mirror 10 shown in FIG. 1 was manufactured by the following method. First, the aluminum nitride sintered substrate 11b, which is the AlN layer 11b, is heat-treated at 1300 ° C. for 1 hour in the air to form a 3.0 μm thick porous Al on the surface of the sintered substrate 11b.
_{A 2} O ₃ layer was formed. This aluminum nitride sintered substrate 11
A suspension in which glass particles are uniformly dispersed in a solvent is applied by spray coating on the Al ₂ O ₃ layer formed on one surface of b, and dried at 150 ° C. for 30 minutes to form a glass particle layer did. Then bake at 1000 ° C for 30 minutes,
The glass of the glass particle layer was softened. As a result, the glass layer 12 was formed on one surface of the aluminum nitride sintered body via the Al ₂ O ₃ layer and the glass-mixed Al ₂ O ₃ layer in this order.

Next, the base 11a was formed of Cu, and the aluminum nitride sintered substrate 11b was laminated and adhered to the base 11a by the DBC method. That is, while the other surface of the aluminum nitride sintered substrate 11b is overlaid on one surface of the base 11a, a load of 2.0 kgf / cm ² is applied thereto, and the resultant is heated to 1065 ° C. in an N ₂ atmosphere to laminate and bond. As a result, a substrate 11 was obtained. Next, an Au thin film 13 having a thickness of 1 μm was formed on the glass layer 12. This Au thin film 13
Is an organic compound containing 27% by weight of Au, 0.1% by weight of Pb, 0.2% by weight of Bi, and 0.1% by weight of Si as other metal components, and α-terpineol and ethyl cellulose as the rest. The paste was formed by applying an Au organic compound paste made of an organic substance such as the above by a spray coating method, drying and baking at 700 ° C. for 10 minutes.

<Embodiment 2> Although not shown, the glass layer 12
The configuration is the same as that of the first embodiment, except that the thin film formed thereon is an Ag thin film. The Ag thin film contains 15% by weight of Ag, and 0.1% by weight of Pb as another metal component.
An organic compound containing 0.2% by weight of Si and 0.1% by weight of Si, and an organic paste containing an organic material such as α-terpineol and ethylcellulose in the remainder are applied by a spray coating method, dried, and then dried at 700 ° C.
For 10 minutes.

<Embodiment 3> Although not shown, the glass layer 12
The structure is the same as that of the first embodiment, except that the thin film formed thereon is an Al thin film. 5% by weight of Al thin film
An organic compound containing 0.2% by weight of Pb, 0.2% by weight of Bi, and 0.1% by weight of Si as other metal components, and the balance being an Al organic material composed of organic substances such as α-terpineol and ethyl cellulose. After the compound paste was applied by a spray coating method and dried, it was formed by baking at 600 ° C. for 10 minutes.

<Embodiment 4> As shown in FIG. 2, the structure is the same as that of Embodiment 1 except that a laminate 21 is formed on the glass layer 12, and the same reference numerals in FIG. Indicates the same part. The laminated body 21 of the reflecting mirror 20 has a thickness of 6
ZnS thin film as high refractive index layer 22 of 0 nm and thickness 100
An MgF ₂ thin film, which is a low-refractive index layer 23 of nm, was alternately laminated five times by a vacuum deposition method.

Embodiment 5 The reflecting mirror 30 shown in FIG. 3 was manufactured by the following method. First, an aluminum nitride sintered substrate 11b, which is an AlN layer 11b, is
After heat treatment for a time, a porous Al ₂ O ₃ layer having a thickness of 3.0 μm was formed on the surface of the sintered substrate 11b. A suspension in which glass particles are uniformly dispersed in a solvent is applied on the Al ₂ O ₃ layer formed on one surface of the aluminum nitride sintered substrate 11b by a spray coating method, and dried at 150 ° C. for 30 minutes. To form a glass particle layer. Subsequently, it was baked at 1000 ° C. for 30 minutes to soften the glass of the glass particle layer. As a result, Al ₂ O is formed on one surface of the aluminum nitride sintered body.
_The glass layer 12 was formed in this order via _three layers and a glass-mixed Al ₂ O ₃ layer.

The base 11a is made of Cu, and is made of Ag.
The aluminum nitride sintered substrate 11b was laminated and adhered to the base 11a via the foil of the Cu-Ti brazing material 31 by the active metal method. That is, a load of 2.0 kgf / cm ² is applied to the aluminum nitride sintered substrates 11 b on one side of the base 11 a with the brazing material 31 interposed therebetween, and 850 in a vacuum.
The laminate was bonded by heating to ℃. The configuration other than the above is the same as that of the first embodiment. In FIG. 3, the same reference numerals as those in FIG.

<Embodiments 6 to 8> Although not shown, the embodiment 6
In Nos. 1 to 8, an aluminum nitride sintered substrate 11b was formed on a base 1 by an active metal method via an Ag—Cu—Ti brazing foil.
Except for laminating and adhering to 1a, the configurations were as in Examples 2 to 4
And are respectively the same.

<Embodiment 9> Although not shown, the AlN layer 11
b, the aluminum nitride sintered substrate 11b
Heat treatment was performed at 1300 ° C. for 1 hour to form a porous Al ₂ O ₃ layer having a thickness of 3.0 μm on the surface of the sintered substrate 11b. A formed on one surface of the aluminum nitride sintered substrate 11b
A suspension of glass particles are uniformly dispersed in a solvent on the l ₂ O ₃ layer was applied by spray coating method to form a glass particle layer was dried for 30 minutes at 0.99 ° C.. Then 10
The glass of the glass particle layer was softened by baking at 00 ° C. for 30 minutes. Thus, a glass layer 12 was formed on one surface of the aluminum nitride sintered body in this order via an Al ₂ O ₃ layer and a glass-mixed Al ₂ O ₃ layer.

Next, Au having a thickness of 1 μm is formed on the glass layer 12.
A thin film 13 was formed. This Au thin film 13 has Au
0.1% by weight of Pb as another metal component,
An organic compound containing 0.2% by weight of Bi and 0.1% by weight of Si, and an Au organic compound paste consisting of an organic substance such as α-terpineol or ethyl cellulose with the remainder being applied by a spray coating method and dried, and then dried.
It was formed by baking at 0 ° C. for 10 minutes. Base 1
1a was formed of Al, and the aluminum nitride sintered substrate 11b was laminated and adhered to the base 11a via an Al-Si brazing material foil. That is, a load of 2.0 kgf / cm ² is applied to the aluminum nitride sintered substrates 11 b with the brazing material 31 sandwiched on one side of the base 11 a, and the
The laminate was bonded by heating to 30 ° C. The configuration other than the above is the same as that of the first embodiment.

<Examples 10 to 12> Although not shown, in Examples 10 to 12, the aluminum nitride sintered substrate 11b was laminated and bonded to a base 11a made of Al via an Al-Si brazing material foil. Except for the above, the configuration is the same as each of the second to fourth embodiments.

Comparative Example 1 A reflecting mirror having the same configuration as that of Example 1 was used as Comparative Example 1 except that the substrate was made of AlN alone and had the same shape as the substrate of Example 1. <Comparative Example 2> A reflective mirror in which a substrate was formed of AlN in the same shape as the substrate of Example 1 and an Au thin film was formed on the surface of the substrate via a Ni plating layer in the same manner as in Example 1 was used as Comparative Example 2. . Table 1 summarizes the configurations of Examples 1 to 12 and Comparative Examples 1 and 2.

[0032]

[Table 1]

<Comparative Tests and Evaluations> The reflective mirrors of Examples 1 to 12 and Comparative Examples 1 and 2 were each subjected to a comparative test of the light reflectance. Table 2 shows the results. The reflectance is obtained by measuring the total reflectance when a light beam having a wavelength of 1.0 μm and Ag and an Al laminate is irradiated with a light beam of 0.55 μm using a spectrophotometer. The surface on which the thin film or the laminate is formed is exposed to air at 500 ° C.
The appearance of the laminate after heating for 100 hours was determined visually. Further, the adhesion of the thin film or the laminate to the substrate was subjected to a peeling (peeling) test of the laminate after the above-mentioned aging treatment, and judged by the peeled portion or the broken portion.

[0034]

[Table 2]

As is clear from Table 1, the reflectance in Comparative Example 2 having no glass layer was 75%, and the reflectance in Comparative Example 1 having a glass layer was 78%. In Examples 1 to 12 having a glass layer on a substrate, the reflectance is 97 to 98%.
showed that. In addition, while the reflection mirrors of Comparative Examples 1 and 2 were fogged by the high heat treatment, the thin films or the laminates of Examples 1 to 12 showed no change and showed high heat resistance. This is considered to be the difference between the base of AlN alone and the base with AlN bonded to the base, and the difference due to the presence or absence of the glass layer. Furthermore, in the peeling test, peeling occurred between the thin film and the substrate in the reflecting mirror of Comparative Example 2, while the reflecting mirrors of Comparative Example 1 and Examples 1 to 12 were broken in the substrate.

[0036]

As described above, according to the reflector of the present invention, even if the surface roughness of the sintered body is large, the main glass layer flattens the surface, and the thin film or the thin film formed on the glass layer The surface of the laminate is a mirror surface without distortion. In addition, since a thin film or a laminate is formed on an AlN layer made of an aluminum nitride sintered body via a glass layer, high heat resistance and heat dissipation are provided. In particular, the present invention exerts excellent effects on reflectance characteristics and heat resistance as compared with conventional reflecting mirrors. Further, a base made of an inexpensive metal material and an AlN
Since it is composed of the layers, the reflector can be manufactured at a lower cost as compared with the substrate made of AlN alone.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a reflecting mirror according to a first embodiment of the present invention and an enlarged sectional view thereof.

FIG. 2 is a view corresponding to FIG. 1, showing a reflecting mirror according to a fourth embodiment of the present invention;

FIG. 3 is a view corresponding to FIG. 1 showing a reflecting mirror according to a fifth embodiment of the present invention.

[Explanation of symbols]

 10, 20, 30 Reflecting mirror 11 Base 11a Base 11b AlN layer 12 Glass layer 13 Thin film 21 Stack 22 High refractive index layer 23 Low refractive index layer 31 Brazing material

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Kunio Sugamura, Inventor 1-297 Kitabukurocho, Omiya City, Saitama Prefecture Mitsubishi Materials Corporation Research Laboratory

Claims (7)

[Claims] The thin film (13) or the laminate (21) is formed by forming a thin film (13) or a laminate (21) on one surface of a substrate (11).
(21) In a reflecting mirror (10, 20, 30) having a reflecting surface formed on a surface thereof, the base (11) is directly or through a brazing material on a base (11a) made of a metal material and the base (11a). A bonded by lamination
1N layer (11b), a glass layer (12) is formed on the AlN layer (11b), and the thin film (13) or the laminate (21) is formed on the glass layer (12). A reflector. 2. The thin film is made of Au thin film (13), Ag thin film or Al thin film.
2. The reflector according to claim 1, wherein the reflector is a thin film having a thickness of 0.01 to 10 [mu] m. 3. The reflector according to claim 1, wherein the laminate (21) is formed by alternately laminating a high refractive index layer (22) and a low refractive index layer (23) a plurality of times. 4. The glass layer (12) has a thickness of 0.1 μm to 100 μm.
The reflecting mirror according to claim 1, wherein the reflecting mirror is formed to have a thickness of: 5. The reflector according to claim 1, wherein the base is made of W, Al, Cu or an alloy thereof. 6. The reflector according to claim 1, wherein the base is made of Cu, and the brazing material is an Ag-Cu-Ti brazing material. 7. The reflector according to claim 1, wherein the base is made of Al and the brazing material is an Al—Si brazing material.