JP2007193132A - Method for manufacturing optical component - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing an optical component, by which such a trouble can be avoided effectively that a substrate is warped or an optical thin film is exfoliated due to the internal stress of the optical thin film. <P>SOLUTION: The method for manufacturing the optical component comprises the steps of: preliminarily depositing a warping layer 2, which warps the substrate to the direction opposite to that of the substrate 1 when the optical thin film 3 is deposited independently on the substrate 1, on the surface opposite to the film deposition surface of the substrate 1 by vapor deposition or sputtering; depositing the optical thin film on the film deposition surface of the substrate after forming the warping layer 2 by vapor deposition or sputtering; and removing the warping layer 2 after the optical thin film 3 is formed. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for manufacturing an optical component having an optical multilayer film.

In general, an optical multilayer filter such as an antireflection film, a half mirror, and a low-pass filter, which is frequently used in an electronic apparatus device, is composed of a multilayer thin film formed on a substrate by vacuum deposition or sputtering.
In vacuum deposition, sputtering, or the like, a multilayer thin film is formed by repeating a process with a large temperature change in which a film is deposited in a heated state and then cooled. In that case, since the coefficient of thermal expansion (thermal contraction rate) differs between the material constituting the thin film and the substrate, stress is generated inside the thin film. In addition, stress is also generated due to volume change when the thin film is solidified. Although this stress is referred to as internal stress, when the thin film has multiple layers, the internal stresses are added together, resulting in extremely large stress as a whole, which may deform the substrate.
Deformation of the substrate not only adversely affects the optical performance of the electronic device, but also easily causes troubles such as peeling of the entire thin film or a part thereof.

  In order to prevent this, conventionally, a method of balancing the force acting on the substrate by the internal stress by forming a thin film on both surfaces of the substrate (for example, Patent Document 1), and the distortion of the substrate caused by the internal stress of the thin film A method of applying a strain of the same magnitude in a reverse direction to the substrate in advance (for example, Patent Document 2), or a combination of a thin film whose internal stress is compressive stress and a thin film whose internal stress is tensile stress A method of reducing the internal stress of the thin film (for example, Patent Document 3), and a method of providing a layer that cancels the internal stress of the thin film between the thin film and the substrate (for example, Patent Document 4) are disclosed.

JP 58-217901 A JP 62-249105 A JP 2003-29024 A JP-A-8-262224

  However, as disclosed in Patent Document 1, it is difficult to form a thin film with high precision so that both surfaces of the substrate satisfy the optical characteristics in the method of forming a film on both surfaces of the substrate. That is, in such a method, a thin film having characteristics that impair the optical performance cannot be used for warpage prevention. Of course, it cannot be applied when a thin film cannot be left on the substrate. Further, as disclosed in Patent Document 2, in the method of pre-straining the substrate, not only a step of deforming the substrate is added, but also it is difficult to balance the stress, resulting in a decrease in productivity. I will. In addition, there is no description of a specific method on how to deform the substrate. From the drawing, it seems to be deformed by polishing or pressing, but it is complicated and extremely expensive to perform such curved surface processing with high accuracy. In addition, a method of manufacturing a multilayer film by combining a thin film having a compressive stress as an internal stress and a thin film having a tensile stress as an internal stress as in Patent Document 3, or between a thin film and a substrate as in Patent Document 4 The method of providing a layer that counteracts the internal stress of the thin film on the substrate is not likely to distort the surface of the substrate because the internal stress of the entire multilayer film is reduced, but the stress balances while satisfying the optical characteristics. In addition, it is difficult to select the material of each layer and the film thickness, and at the part where the thin film having the tensile stress as the internal stress and the thin film having the compressive stress as the internal stress are in contact with each other, There is a problem that it is easy to peel off.

  Accordingly, an object of the present invention is to provide a method for manufacturing an optical component that can effectively avoid troubles such as a substrate being distorted or film peeling due to internal stress of a thin film.

  The optical component manufacturing method of the present invention is an optical component manufacturing method for forming an optical thin film on a substrate, and the optical thin film is formed on the substrate independently on the side surface opposite to the film forming surface of the substrate. A warp imparting layer forming step in which a warp imparting layer formed from a metal or a metal oxide is preliminarily formed by vapor deposition or sputtering, and the warp imparting layer forming step. An optical thin film forming step of forming the optical thin film on the film formation surface of the substrate by vapor deposition or sputtering later, and a removing step of removing the warp imparting layer from the substrate after the optical thin film forming step. .

Here, the warp imparting layer is a thin film that is formed on the substrate, can warp the substrate, and can be removed from the substrate.
According to the method for manufacturing an optical component of the present invention, a warp imparting layer that warps in a direction opposite to the warp generated on the substrate due to the optical thin film and is removable is previously provided on the side opposite to the film formation surface of the substrate ( Hereinafter, it is also formed by vapor deposition or sputtering. Then, when the warp-imparting layer on the back surface is removed after the optical thin film is formed on the substrate, the stress is relieved by the rate at which the warp-imparting layer warps (displaces) in the opposite direction to the optical thin film, Since the substrate is deformed by the applied stress, it is possible to reduce the warpage of the substrate as a result of this warping back. In addition, since the warp preventing layer is removed, its optical properties (transparency, etc.) are not a problem. In particular, it is also effective when the opposite side of the optical thin film forming surface is polished to reduce the weight of the substrate.

In the present invention, since the optical thin film is formed by vapor deposition or sputtering, the thermal stress caused by the difference in linear expansion coefficient between the optical thin film and the substrate and the internal stress caused by the volume change during solidification of the optical thin film ( The degree of warpage of the substrate can be easily estimated from the various sizes and orientations, and can easily be reflected in the conditions for forming the warp imparting layer. Here, the thermal stress is specifically determined from the temperature difference between the time of forming the optical thin film and room temperature, the difference in the linear expansion coefficient between the substrate and the optical thin film, the elastic modulus and Poisson's ratio of each of the substrate and the optical thin film.
In addition, since the formation of the optical thin film and the formation of the warp imparting layer are both performed by vapor deposition or sputtering, the thin film forming apparatus can be made common and the process can be simplified.

Generally, when the temperature of the substrate is raised during the formation of the optical thin film, a stronger and better film can be obtained. Therefore, when the formed optical thin film develops compressive stress, that is, when the optical thin film surface deforms into a convex shape It is preferable to select a material having a larger linear expansion coefficient than that of the substrate as the warp imparting layer and to form it at a temperature lower than the temperature at which the optical thin film is formed. In the present invention, since the warp imparting layer is formed by vapor deposition or sputtering, it becomes easy to select the warp imparting layer forming conditions so that the internal stress generated during solidification also becomes a compressive stress. For example, it is preferable to select conditions that increase the packing density of the warp imparting layer by acting ions or plasma.
Also, when the optical thin film develops tensile stress, that is, when the optical thin film surface is deformed into a concave shape, a material having a smaller linear expansion coefficient than the substrate is selected as the warp imparting layer, and it is formed at a temperature lower than the temperature at which the optical thin film is formed It is desirable to do. In the present invention, since the warp imparting layer is formed by vapor deposition or sputtering, it is easy to select the internal stress generated during solidification to be a tensile stress.
In addition, as a curvature provision layer, it is good also as a 2 layer structure of the base layer which is easy to detach | leave from a board | substrate, and the stress layer which produces curvature stress.

In this invention, it is preferable to provide the organic layer formation process which forms the organic layer which consists of an organic compound in the opposite side to the film-forming surface of the said board | substrate before the said curvature prevention layer formation process.
According to this invention, since the organic layer made of an organic compound is formed before the warp preventing layer is formed on the back surface of the substrate, the warp preventing layer can be peeled off together with the organic layer. For example, the warp preventing layer can be easily peeled off by a solvent that dissolves the organic layer.
The organic compound that forms such an organic layer is preferably an organic polymer such as an epoxy resin.

In the present invention, the organic layer is preferably formed by a dry method.
Here, examples of the dry method include methods such as vapor deposition and sputtering.
According to this invention, since the organic layer is formed by a dry method, it is possible to perform the organic layer formation and the warp prevention layer formation using the same film forming apparatus, and the process can be simplified. As a method for forming the organic layer, for example, a CVD method using an organometallic compound containing silicon as a raw material can be used.

In the present invention, the warp amount d _s based on the warpage imparting layer, the ratio of the warp amount d _h in the case of forming on the substrate the optical thin film alone is indicated by warpage ratio R of formula (1), The warp amount ratio R is preferably 2 to 10.
R = d _s / d _h (1)
[Where R is the amount of warpage when the distance from the floor surface to the top of the substrate recess when the convex portion of the substrate warped in an arc is placed on a flat floor surface is the warpage amount. and warpage d _s based on the layer, which is the ratio of the warp amount d _h in the case of forming on the substrate the optical thin film alone. Measurement of the amount of warpage is performed at the temperature at which the optical thin film is formed. ]

  According to this invention, since the warpage amount ratio R is in a specific range of 2 to 10, if the warp preventing layer that has warped the substrate from the opposite side of the optical thin film is removed, the influence of the warp by the optical thin film is removed. Becomes stronger and the substrate can effectively approach a plane. Here, the warp amount ratio R is more preferably 2 to 5. When R is smaller than 2, the effect of the warp imparting layer is not sufficient, while when R exceeds 10, the effect of the warp imparted layer is too large, and even if the warp imparting layer is removed, the warping back is not sufficient. The substrate may not be flat.

In this invention, it is preferable that the removal method of the said curvature provision layer is a thing by grinding | polishing or washing | cleaning.
According to this invention, since the method for removing the warp imparting layer is polishing or washing, the warp imparting layer can be easily removed.
For example, the removal method by polishing may be either physical polishing or chemical polishing. In physical polishing, the warpage imparting layer is removed by cutting and wearing. As the chemical polishing, for example, electrolytic polishing is suitable. Since the electrolytic polishing is performed electrochemically, unlike the case of physical polishing, there is an advantage that no residual stress is generated because no physical force is applied, and a deteriorated layer is not generated during processing.
As a removal method by washing, a method according to the material of the warpage imparting layer, such as acid washing, alkali washing, or washing with an organic solvent, or the material of the layer existing between the warpage imparting layer and the substrate is appropriately adopted. Good.

In the present invention, the optical component is preferably an optical multilayer filter.
According to the present invention, since the optical component is an optical multilayer filter composed of a substrate with less warpage, for example, a UV-IR cut filter (Ultraviolet-Infrared cut) having less warpage than a conventional optical multilayer filter. filter) and IR cut filter (Infrared cut filter).

In the present invention, the substrate is preferably a glass plate.
According to the present invention, the substrate is formed of a glass plate, so that the desired filter function is integrally formed as a dust-proof glass of an image element such as a CCD (charge coupled device) with little warpage, for example, UV. -An optical multilayer filter including an IR cut filter and an IR cut filter function can be obtained.

In the present invention, the substrate is preferably a quartz plate.
According to the present invention, for example, a UV-IR cut filter and an IR cut filter function which are configured integrally with a desired filter function as an optical low-pass filter with little warpage, for example, with a substrate made of a quartz plate. An optical multilayer filter including this can be obtained.

The electronic device apparatus of the present invention is characterized in that the above-described optical multilayer filter is incorporated.
According to the electronic device of the present invention, since the optical multilayer filter described above is incorporated, for example, video devices such as digital still cameras and digital video cameras, so-called camera-equipped mobile phones, so-called camera-equipped portable personal computers. (Personal computer) can be used effectively.

  The present invention relates to a method of manufacturing an optical component for forming an optical thin film on a substrate, which is opposite to the warp generated on the substrate when the optical thin film is formed on the substrate on the opposite side of the film formation surface of the substrate. A step of forming a warp imparting layer that warps in a direction by vapor deposition or sputtering in advance, a step of forming an optical thin film by vapor deposition or sputtering on a substrate, and a step of removing the warp imparting layer after forming the optical thin film. In the following, an embodiment will be described in detail with reference to the drawings.

[Cutting layer forming step]
FIG. 1 is a schematic cross-sectional view of a multilayer film in which a warp imparting layer 2 is formed on a substrate 1.
As the substrate 1, any substrate such as a glass substrate or a quartz substrate is used. The warp imparting layer 2 needs to be formed on the substrate 1 by vapor deposition or sputtering so that the warp can be given to the substrate 1 and can be removed from the substrate 1.
As shown in FIG. 1, when a warp imparting layer 2 is formed on a smooth substrate 1 and heated to a predetermined temperature (temperature at the time of forming an optical thin film described later), the thermal expansion coefficients of the substrate 1 and the warp imparting layer 2 are obtained. Due to the difference, a warp amount indicated by d _s can be imparted to the substrate 1. Specifically, the distance from the floor surface to the vertex of the substrate recess when the substrate 1 that is warped in an arc is placed on a flat floor surface with the convex portion up is the warpage amount d _s based on the warpage imparting layer 2. is there. This amount of warpage can be measured by, for example, a high precision flatness tester FT-900 (manufactured by Nidec Co., Ltd.).

The warp imparting layer 2 functions to leave a permanent strain (warp) on the substrate 1 even after being removed from the substrate 1.
As a material for the warp imparting layer 2, vapor deposition or sputtering is possible, heat resistance that does not cause peeling or destruction at the temperature at the time of layer formation, and flexibility that can cause the substrate 1 to warp by linear expansion. It is preferable to have. It is also a desirable property that it can be easily removed after the optical thin film described later is formed.
For example, the warp imparting layer 2 is preferably a metal such as aluminum, iron or titanium, or a metal oxide thereof.

In addition, before forming such a warp prevention layer 2, an organic layer made of an organic compound is formed on the back surface of the substrate 1 so that the warp prevention layer 2 can be easily peeled (removed) indirectly with a solvent or the like. It is also preferable. Even if the warp prevention layer 2 itself is strong and has a property of strongly bonding to the substrate 1, the warp prevention layer 2 is indirectly formed by interposing an organic layer that is easy to peel (remove) in the middle. It can be removed.
As an organic compound forming such an organic layer, an organic polymer is preferable. For example, epoxy resin, polyurethane resin, polyester resin, polyethylene, polypropylene, polystyrene, polycarbonate, polyvinyl chloride, polyvinylidene chloride, polyvinyl acetate, polyamide, polyimide, acrylic resin, methacrylic resin, phenol resin, silicone resin, fluorine resin, Nylon resin, ethylene / vinyl acetate resin, styrene / acrylonitrile resin, acrylonitrile / butadiene / styrene resin, and the like. Such organic polymers may be used alone or in combination of two or more. Among such organic polymers, curable epoxy resins, polyurethane resins, and polyester resins are particularly preferable because they have excellent wet film-forming properties (coating properties) and heat resistance.

Furthermore, such an organic layer may be formed by a dry method such as vapor deposition or sputtering. For example, a CVD method using an organometallic compound containing silicon as a raw material can also be used. Examples of organometallic compounds containing silicon include tetraethoxysilane (TEOS), tetramethoxysilane (TMOS), SOB ((CH ₃ ) ₃ SiO) ₃ B), and SOP (((CH ₃ ) ₃ SiO) ₃ PO). , OMCTS (Si ₄ C ₈ H ₂₄ O ₄ ), MCTS (Si ₄ C ₄ H ₁₆ O ₄ ), HMDSO (((CH ₃ ) ₃ Si) ₂ O), DADBS (SiC ₁₂ H ₂₄ O ₆ ), etc. Is mentioned.

[Optical thin film formation process]
FIG. 2 is a schematic cross-sectional view of the multilayer film when the optical thin film 3 is formed alone on the substrate 1. If such a multilayer film is intended for an optical multilayer film filter, for example, TiO ₂ , Ta ₂ O ₅ , Nb ₂ as a material for the high refractive index material layer by an ion plating method or an ion assist method. It can be formed by using O ₅ or the like and alternately laminating using SiO ₂ , MgF ₂ or the like as the material of the low refractive index material layer.
As shown in FIG. 2, the substrate 1, it is observed warping indicated by warpage d _h at a temperature of at optical thin film formation.

Here, the warpage amount ratio R represented by the following formula (1) is preferably 2 to 10, and more preferably 2 to 5.
R = d _s / d _h (1)
If R is smaller than 2, the effect of the warp imparting layer 2 is not sufficient. Conversely, if R exceeds 10, the effect of the warp imparting layer 2 is too strong. Later, it becomes difficult for the substrate 1 to become flat.
FIG. 3 is a schematic cross-sectional view of a multilayer film in which the optical thin film 3 is formed on the opposite side after the warp imparting layer 2 is formed on the substrate 1. As shown in FIG. 3, the warp of the substrate 1 is somewhat reduced due to the influence of the optical thin film 3, but the warp effect given by the warp imparting layer 2 is still large, and the warp still remains on the substrate 1.

[Removal process of warp imparting layer]
FIG. 4 is a schematic cross-sectional view of the optical multilayer film 10 including the substrate 1 and the optical thin film 3 after the warp imparting layer 2 is removed from the multilayer film of FIG.
The method for removing the warp imparting layer 2 may be appropriately employed depending on the material of the warp imparting layer 2 as described above. For example, if aluminum is deposited, the warp imparting layer 2 can be easily removed by acid cleaning.

According to the above-described embodiment, the following effects can be obtained.
(1) Warp in a direction opposite to the warp generated in the substrate 1 due to the optical thin film 3, and a removable warp imparting layer 2 is formed on the back surface of the substrate 1 in advance, and then warp on the back surface is applied. Since the layer 2 is removed, the stress is relaxed by the rate that the warp imparting layer 2 is displaced in the direction opposite to that of the optical thin film 3, and the substrate is deformed by the stress generated by the optical thin film 3. As a result, the warp of the substrate 1 is reduced. As a result, a multilayer film 10 with less warpage as shown in FIG. 4 is obtained. For example, as shown in FIG. 5, the multilayer film 10 can be used as an electronic apparatus device 400 including an optical multilayer film filter 10 with little optical distortion.

(2) Since the warp imparting layer 2 is finally removed, its optical properties (transparency, etc.) are not considered a problem. Therefore, it is possible to select from various kinds of materials such as metals and metal oxides in consideration of the coefficient of thermal expansion, so that the degree of freedom in material selection is high.
(3) Since the thing which vapor-deposited the metal as the curvature provision layer 2 can be easily removed by acid washing, it is excellent in convenience. Further, the warp imparting layer 2 can be removed indirectly by forming an organic layer that is easily peeled (removed) as a base layer of the warp imparting layer 2.

(4) Further, since the warpage preventing layer 2 is removed, it is effective when the surface after removal is polished to reduce the weight of the substrate.
(5) and the warp amount d _s based on the warp imparting layer 2, a specific range and warpage ratio R 2-10 is the ratio between the warp amount d _h in the case of forming the substrate 1 of the optical thin film 3 alone When the warp preventing layer 2 that has warped the substrate 1 from the opposite side of the optical thin film 3 is removed, the influence of the warp by the optical thin film 3 becomes strong, and the substrate 1 effectively approaches a plane. Can do. By using such parameters, the warpage prevention layer 2 can be designed quantitatively.

Hereinafter, the present invention will be described in detail based on examples and drawings. However, the present invention is not limited to these examples. In each example, components having the same structure and function as those in the embodiment will be described with the same reference numerals.
[Example 1]
This example is an optical multilayer filter (UV-IR cut) having a good reflection characteristic that passes through the visible wavelength region and has little absorption of light in the ultraviolet wavelength region below the predetermined wavelength and the infrared wavelength region above the predetermined wavelength. It is an example applied to manufacture of a filter.

(Formation of warpage imparting layer 2)
A white plate glass (n = 1.52, thickness: 0.7 mm) having a diameter of 30 mm is used as the material of the substrate 1, and a warp imparting layer is formed on the opposite side (back surface) of the surface on which the optical thin film 3 described later is formed as follows. 2 was formed.
Metal aluminum was formed to a thickness of 3 μm on the back surface of the substrate 1 by non-heated ion-assisted vapor deposition. The aluminum film generates tensile stress in normal vapor deposition, but can be made compressive stress by strengthening the assist conditions. The substrate 1 on which the aluminum was formed and formed on the back surface had a warp _ds of 53 μm at 200 ° C.
Incidentally, when performing alone the formation of optical thin film to be described later (without forming the warp imparting layer), warp amount d _h occurring at the same temperature was 9 .mu.m, therefore, warpage ratio R was 5.

(Formation of optical thin film 3)
Next, an optical thin film (multilayer film) was formed on the opposite side of the substrate 1 on which the warp imparting layer 2 was formed. The material of each layer of the used multilayer film is Ta ₂ O _{5 for} the high refractive index layer (H) and SiO ₂ for the low refractive index layer (L). In addition to these, commonly used vapor deposition materials such as TaO ₂ and Nb ₂ O ₅ can be used as the high refractive index layer (H), and MgF ₂ can be used as the low refractive index layer (L).
The film thickness of the high refractive index layer (H) is marked with the value of optical film thickness nd = 1 / 4λ being 1H, and the film thickness is designed wavelength λ of 755 nm, 1.14H, 1.09L, 1 from the substrate 1 side. .03H, 1.01L, (0.99H, 0.99L) 6, 1.02H, 1.08L, 1.31H, 0.18L, 1.37H, 1.24L, 1.27H, 1.28L, (1.28H, 1.28L) There were 40 layers of 6, 1.26H, 1.28L, 1.25H, 0.63L. The total film thickness (physical film thickness) was 4.6 μm. As a film forming method, an ordinary ion plating method was used. The temperature during film formation is 200 ° C.
By this film formation, SiO ₂ (strong compressive stress) / TiO ₂ (weak compressive stress) has a force that pushes back the warp by the warp imparting layer 2 so that the optical thin film (optical multilayer film) 3 side is convex. applied to the substrate 1, but since the stress due to warping imparting layer 2 is winning, resulting in warpage d _s is only reduced to 30 [mu] m.

(Removal of warp imparting layer 2)
It returned to room temperature (25 degreeC), and it immersed in the sulfuric acid for 1 hour, and the aluminum film of the back surface which is the curvature provision layer 2 was removed. The warping amount of the final product after removing the aluminum film showed a very small value of 1.0 μm.

In Example 1, although demonstrated using the white plate glass as the board | substrate 1, it is not limited to this, Transparent substrates, such as BK7, sapphire glass, borosilicate glass, blue plate glass, SF3, and SF7, may be sufficient. In general, commercially available optical glasses can also be used. Alternatively, a quartz substrate may be used.
Although the case where TiO ₂ is used as the material of the high refractive index material layer has been described, Ta ₂ O ₅ and Nb ₂ O ₅ can also be applied. Although described in the case of using SiO ₂ as the material of low refractive index material layer, it is possible to apply the MgF _2.
The optical thin film 3 is formed by the ion plating method, but may be an ion assist method.

[Example 2]
Below, the electronic device apparatus comprised including the optical multilayer film filter 10 of Example 1 is demonstrated. The present embodiment is an embodiment applied as an electronic apparatus apparatus to, for example, an imaging apparatus of a digital still camera that captures a still image.
FIG. 5 is an explanatory diagram illustrating a configuration example of the electronic device according to the present invention, and illustrates a configuration example of an imaging module and an imaging device including the imaging module.

The imaging module 100 shown in FIG. 5 includes an optical multilayer filter 10, an optical low-pass filter 110, a CCD (charge coupled device) 120 that electrically converts an optical image, and a drive that drives the imaging element 120. The unit 130 is configured.
As described in the first embodiment of the present invention, the optical multilayer filter 10 includes the glass substrate 1 and the optical thin film 3, and has an IR cut filter function. The optical multilayer filter 10 is integrally formed by being bonded to the CCD 120 on the front surface of the CCD 120, and has the dust-proof glass function of the CCD 120.

  The imaging apparatus 400 can be configured by including the imaging module 100, the lens 200 disposed on the light incident side, and the main body unit 300 that records and reproduces the imaging signal output from the imaging module 100. . Although not shown, the main body unit 300 includes a signal processing unit that corrects an imaging signal, a recording unit that records the imaging signal on a recording medium such as a magnetic tape, a reproducing unit that reproduces the imaging signal, and a reproduction unit. A component such as a display unit for displaying the recorded video is included.

The digital still camera configured in this way is equipped with an optical multilayer film filter 10 that is integrally provided with a CCD 120, a dustproof glass function, and an IR cut filter function. A camera can be provided.
In addition, although the imaging module 100 of the embodiment has been described with a structure in which the lens 200 is disposed separately, the imaging module may be configured including the lens 200 as well.

  The method for producing an optical component of the present invention can be suitably used in the field of electronic equipment as a method for producing an optical multilayer filter or the like with little substrate warpage.

The schematic sectional drawing which shows the structure of the multilayer film (a board | substrate and an optical thin film) concerning this embodiment. The schematic sectional drawing which shows the structure of the multilayer film (a board | substrate and a curvature provision layer) in the said embodiment. The schematic sectional drawing which shows the structure of the multilayer film (a board | substrate, an optical thin film, and a curvature provision layer) in the said embodiment. FIG. 2 is a schematic cross-sectional view showing a configuration of an optical multilayer film in the embodiment. 1 is a block diagram showing an outline of an electronic apparatus device (imaging device) in an embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Board | substrate (glass substrate), 2 ... Warp provision layer, 3 ... Optical thin film, 10 ... Optical multilayer film (optical multilayer film filter), 100 ... Imaging module, 110 ... Optical low-pass filter, 120 ... Imaging element, 130 ... Drive , 200 ... lens, 300 ... main body, 400 ... electronic device (imaging device)

Claims (6)

An optical component manufacturing method for forming an optical thin film on a substrate,
When the optical thin film is formed on the substrate alone on the side opposite to the film forming surface of the substrate, the warp is imparted in a direction opposite to the warp generated in the substrate, and the warp is formed from metal or metal oxide. A warp imparting layer forming step of forming a layer in advance by vapor deposition or sputtering;
An optical thin film forming step of forming the optical thin film by vapor deposition or sputtering on the film forming surface of the substrate after the warp imparting layer forming step;
And a removing step of removing the warp imparting layer from the substrate after the optical thin film forming step. In the manufacturing method of the optical component according to claim 1,
An optical component manufacturing method comprising an organic layer forming step of forming an organic layer made of an organic compound on the side surface opposite to the film forming surface of the substrate before the warp preventing layer forming step. In the manufacturing method of the optical component according to claim 2,
A method of manufacturing an optical component, wherein the organic layer is formed by a dry method. In the manufacturing method of the optical component in any one of Claims 1-3,
Wherein the amount of warpage d _s based on warp-imparting layer, the ratio of the warp amount d _h in the case of forming on the substrate the optical thin film alone is indicated by warpage ratio R of formula (1), the warpage amount ratio R is 2-10, The manufacturing method of the optical component characterized by the above-mentioned.
R = d _s / d _h (1)
[Wherein R is the amount of warp when the distance from the floor surface to the top of the substrate recess when the convex portion of the substrate warped in an arc is placed on a flat floor surface is the amount of warpage. and warpage d _s based on the layer, which is the ratio of the warp amount d _h in the case of forming on the substrate the optical thin film alone. Measurement of the amount of warpage is performed at the temperature at which the optical thin film is formed. ] In the manufacturing method of the optical component in any one of Claims 1-4,
A method for producing an optical component, wherein the method for removing the warp imparting layer is by polishing or washing. In the manufacturing method of the optical component in any one of Claims 1-5,
A method of manufacturing an optical component, wherein the optical component is an optical multilayer filter.

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