JP2013167844A - Wavelength variable interference filter, optical module, electronic equipment and method for manufacturing wavelength variable interference filter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an etalon in which thickness variation in a thin part of a diaphragm can be decreased and a gap dimension between reflection films can be set with high accuracy.SOLUTION: An etalon comprises: a first substrate 10 having a light-transmitting first base material 11; a second substrate 20 having a light-transmitting second base material 21 opposing to the first substrate 10 and including a diaphragm 23; a first reflection film 17 disposed on a surface of the first substrate 10 opposing to the second substrate 20; a second reflection film 27 disposed on the diaphragm 23 of the second substrate 20 and opposing to the first reflection film 17 via the gap; and an electrostatic actuator 40 setting a dimension of the gap. The diaphragm 23 includes: a movable part 23a which is movable in a direction toward or parting from the first reflection film 17 and in which the second film 27 is disposed; and a thin part 23b which supports the movable part 23a and in which a recess with a depth in the same dimension as the thickness of the second base material 21 is formed. A spin-on-glass film 26 is formed in the thin part 23b.

Description

  The present invention relates to a wavelength tunable interference filter, an optical module, an electronic apparatus, and a method for manufacturing the wavelength tunable interference filter.

2. Description of the Related Art A variable wavelength interference filter (hereinafter sometimes referred to as an etalon) is known in which two reflective films are opposed to each other through a gap, and light having a specific wavelength is selected from incident light and emitted.
Patent Document 1 discloses a Fabry-Perot filter (wavelength variable interference filter) that includes a fixed substrate and a movable substrate, has a diaphragm on the movable substrate, and can vary the gap dimension between a pair of reflective films.

JP 2003-57438 A

In the diaphragm shown in Patent Document 1, a thin portion is formed by etching a substrate. For this reason, the thickness of the thin portion may vary. In particular, when the etching amount is large, the thickness variation of the thin portion becomes large, and the etching processing amount is limited.
For example, when adjusting the gap dimension between the reflective films using a gap dimension setting means such as an electrostatic actuator, if the thickness of the thin part varies, the deflection of the thin part becomes non-uniform, and the gap dimension between the reflective films is There is a problem that variation and spectral accuracy are lowered.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

  Application Example 1 A tunable interference filter according to this application example includes a first substrate having a light-transmitting first base material, and a light-transmitting second base material having a diaphragm facing the first substrate. A first reflection film provided on a surface of the first substrate facing the second substrate, and provided on the diaphragm of the second substrate, through the gap with the first reflection film. And a gap dimension setting means for setting the dimension of the gap, and the diaphragm is movable in a direction toward or away from the first reflection film, and the second reflection film is disposed. A movable portion that is supported, and a thin-walled portion that supports the movable portion and is formed with a recess having a depth that is the same as the thickness of the second base material, and a spin-on-glass film is provided on the thin-walled portion. It is characterized by being.

  According to this configuration, the spin-on glass film is provided on the thin portion of the diaphragm in the second substrate. The thin part is not provided with the second base material, and the spin-on-glass film forms the main thickness. For this reason, the thickness of the thin portion can be formed without variation. And the bending of a thin part becomes uniform, the gap dimension between reflection films can be set with sufficient accuracy, and a wavelength variable interference filter excellent in spectral accuracy can be provided.

  Application Example 2 In the wavelength tunable interference filter according to the application example, the second substrate is resistant to the spin-on-glass film on one surface of the second base material and a solution for etching the second base material. The thin-walled portion is formed with the spin-on-glass film facing the first substrate, and the etching resistant film is exposed on a surface opposite to the surface facing the first substrate. Are preferably provided.

According to this configuration, the spin-on glass film is formed on the thin portion so as to face the first substrate, and the etching resistant film is exposed on the surface opposite to the surface facing the first substrate.
For this reason, by performing the etching process from the surface opposite to the surface facing the first substrate of the second base material, the etching resistant film functions as an etching stop film, and affects the thickness of the thin portion by the etching process. Don't give.

  Application Example 3 In the wavelength tunable interference filter according to the application example, the movable portion includes the etching resistant film and the spin-on-glass film laminated on one surface of the second base material, and the thickness direction of the second base material In the plan view, it is preferable that the etching-resistant film is not formed on a part of the portion overlapping the second optical film.

According to this configuration, the etching resistant film is not formed on a part of the portion overlapping the second optical film in a plan view in the thickness direction of the second base material.
In this structure, even a material that does not allow light to pass through as an etching resistant film can be used by not forming it in a portion through which light passes, and the degree of freedom in design is widened. Further, when the etching resistant film is an opaque film such as a metal material, it can function as an aperture film that blocks stray light.

  Application Example 4 In the wavelength tunable interference filter according to the application example described above, a first drive electrode provided on a surface of the first substrate facing the second substrate as the gap dimension setting unit, and the second substrate It is preferable that a second drive electrode provided on a surface facing the first substrate and facing the first drive electrode is provided.

According to this configuration, the first drive electrode is disposed on the first substrate and the second drive electrode is disposed opposite to the second substrate as the gap dimension setting means.
The gap dimension between the reflective films functions as an electrostatic actuator by applying a voltage to the first drive electrode and the second drive electrode, and utilizes the electrostatic force acting between the first reflective film and the second reflective film. Can be set.

  Application Example 5 An optical module according to this application example includes a first substrate having a light-transmitting first base material, and a light-transmitting second base material having a diaphragm facing the first substrate. A second substrate, a first reflective film provided on a surface of the first substrate facing the second substrate, and a diaphragm provided on the diaphragm of the second substrate, facing the first reflective film via a gap A second reflective film, a gap dimension setting means for setting the dimension of the gap, and a light receiving unit for receiving light transmitted through the reflective film, wherein the diaphragm approaches the first reflective film Or a movable part that is movable in a direction away from the second reflection film and a thin-walled part that supports the movable part and has a recess having the same depth as the thickness of the second substrate. However, a spin-on-glass film is provided on the thin part. The features.

According to this configuration, since the spin-on-glass film is formed on the thin portion of the diaphragm, the thickness of the thin portion can be formed without variation, and the gap dimension between the reflective films can be set with high accuracy.
Thus, an optical module with excellent spectral accuracy can be provided.

  Application Example 6 An electronic apparatus according to this application example includes a first substrate having a light-transmitting first base material, and a light-transmitting second base material having a diaphragm facing the first substrate. A second substrate, a first reflective film provided on a surface of the first substrate facing the second substrate, and a diaphragm provided on the diaphragm of the second substrate, facing the first reflective film via a gap Based on the light received by the light receiving unit, the light receiving unit that receives the light transmitted through the reflective film, the gap size setting unit that sets the size of the gap, An analysis processing unit for analyzing characteristics, and the diaphragm supports the movable unit, a movable unit movable in a direction approaching or moving away from the first reflective film, and the second reflective film is disposed. A recess having a depth the same as the thickness of the second substrate is formed. It has a thin portion which is, and wherein the spin-on-glass film is formed on the thin portion.

According to this configuration, since the spin-on-glass film is formed on the thin portion of the diaphragm, the thickness of the thin portion can be formed without variation, and the gap dimension between the reflective films can be set with high accuracy.
Thus, an electronic device having excellent spectral accuracy can be provided.

  Application Example 7 A method of manufacturing a wavelength tunable interference filter according to this application example includes a step of forming an etching mask on the surface of the first base material, a step of etching the etching mask as a mask to form a recess, Forming a first drive electrode in the recess of the first substrate; forming a first reflective film on the first substrate; and having resistance to an etching solution on one surface of the second substrate. Forming an etching film; forming a spin-on-glass film on the etching-resistant film; and forming an etching mask on a surface of the second substrate opposite to the surface on which the spin-on-glass film is formed. Etching the etching mask as a mask to form a thin portion, forming a second drive electrode on the second base material, and forming a second reflective film on the second base material Bonding the first base material on which the first drive electrode and the first reflective film are formed and the second base material on which the second drive electrode and the second reflective film are formed, and It is characterized by having.

  According to this method of manufacturing a wavelength tunable interference filter, by providing an etch-resistant film on the spin-on-glass film, the spin-on-glass film is not etched, and etching is stopped by the etch-resistant film, so that the etching time can be easily managed. is there. And the thickness of a thin part can be formed without dispersion | variation, and the wavelength variable interference filter excellent in spectral accuracy can be manufactured.

  Application Example 8 In the method of manufacturing the wavelength tunable interference filter according to the application example, after forming the etching resistant film, a step of removing a part of the etching resistant film corresponding to the second reflective film. It is preferable to include.

According to this method of manufacturing a wavelength tunable interference filter, a part of the etching resistant film formed on one surface of the second substrate is removed.
For this reason, even a material that does not transmit light can be used as the etching resistant film, and the degree of freedom in designing the wavelength variable interference filter is increased.

The top view which shows the structure of the etalon in 1st Embodiment. Sectional drawing which shows the structure of the etalon in 1st Embodiment. The manufacturing process figure explaining the manufacturing method of the etalon in 1st Embodiment. The manufacturing process figure explaining the manufacturing method of the etalon in 1st Embodiment. The manufacturing process figure explaining the manufacturing method of the etalon in 1st Embodiment. The manufacturing process figure explaining the manufacturing method of the etalon in 1st Embodiment. The manufacturing process figure explaining the manufacturing method of the etalon in 1st Embodiment. Sectional drawing which shows the structure of the etalon in 2nd Embodiment. The manufacturing process figure explaining the manufacturing method of the etalon in 2nd Embodiment. The manufacturing process figure explaining the manufacturing method of the etalon in 2nd Embodiment. The manufacturing process figure explaining the manufacturing method of the etalon in 2nd Embodiment. The block diagram which shows the structure of the color measurement apparatus as an electronic device in 3rd Embodiment. Sectional drawing which shows the structure of the gas detection apparatus as an electronic device in 4th Embodiment. The circuit block diagram of the gas detection apparatus in 4th Embodiment. The block diagram which shows the structure of the food analyzer as an electronic device in 5th Embodiment. The perspective view which shows the structure of the spectroscopic camera as an electronic device in 6th Embodiment.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, embodiments of the invention will be described with reference to the drawings. In the drawings used for the following description, the ratio of dimensions of each member is appropriately changed so that each member has a recognizable size.
[First Embodiment]

FIG. 1 is a plan view showing the configuration of the etalon of this embodiment. 2 is a cross-sectional view taken along the line AA in FIG.
(Configuration of Etalon 1)
As shown in FIG. 1, the etalon 1 is a square plate-like optical member in plan view, and one side is formed, for example, at 10 mm. As shown in FIG. 2, the etalon 1 includes a first substrate 10 and a second substrate 20.
The first substrate 10 is, for example, quartz glass, soda glass, crystalline glass, lead glass, potassium glass, borosilicate glass, non-alkali glass, or other glass, and a first substrate 11 having translucency such as crystal. And is formed by etching the first base material 11. Similarly, the second substrate 20 is a second substrate having translucency such as quartz glass, soda glass, crystalline glass, lead glass, potassium glass, borosilicate glass and non-alkali glass, and crystal. It has the material 21 and is formed by etching the second base material 21.

The etalon 1 is integrally formed by joining the first substrate 10 and the second substrate 20. This bonding is fixed by bonding bonding films 19 and 29 provided at the bonding portions of the first substrate 10 and the second substrate 20. As the bonding films 19 and 29, plasma polymerized films mainly composed of polyorganosiloxane are employed.
Moreover, in joining methods other than those described above, joining using an adhesive material such as an adhesive, joining using a metal film, or the like can be used.

For the first substrate 10, a first base material 11 having a thickness of, for example, 500 μm is used. The first substrate 10 has a stepped shape in which a circular first concave portion 12 is provided in the center of the first substrate 10 by etching, and the central portion is recessed by one step.
In addition, a support portion 13 that supports the second substrate 20 in the bonding with the second substrate 20 is provided at the outer edge of the first substrate 10.

A first reflective film 17 is formed at the center of the first recess 12. The first reflective film 17 has light reflection characteristics and transmission characteristics, and is formed of a metal film such as Ag or an Ag alloy with a thickness of, for example, 50 nm. Note that the first reflective film 17 may be formed of a dielectric multilayer film.
A ring-shaped first drive electrode 18 is formed so as to surround the first reflective film 17 in plan view. The first drive electrode 18 is formed at a level higher than the center of the first recess 12. The first drive electrode 18 is connected to the extraction electrode 18a.
The first drive electrode 18 and the extraction electrode 18a are conductive films, for example, an ITO (Indium Tin Oxide) film. These conductive films may be Cr / Au films having a Cr film as a base and an Au film laminated thereon.

The lead electrode 18 a is connected to a connection pad 16 a formed at one of the four corners of the first substrate 10.
In this way, the first drive electrode 18 is electrically connected to the connection pad 16a via the lead electrode 18a.
A bonding film 19 is formed on the upper surface of the support portion 13.

The second substrate 20 is formed by using a second substrate 21 having a square shape, for example, by processing one surface of the second substrate 21 having a thickness of 200 μm by etching.
The second substrate 20 has a diaphragm 23. The diaphragm 23 includes a columnar movable portion 23a centered on the center of the substrate, and a thin portion 23b that holds the movable portion 23a around it and is thinner than the movable portion 23a.

In the thin portion 23b, an annular second recess 22 is formed by etching the second base material 21 on the surface opposite to the surface facing the first substrate 10. This 2nd recessed part 22 is the depth of the same dimension as the thickness of the 2nd base material 21, and the 2nd base material 21 is etched in the thickness direction in the thin part 23b, and the 2nd base material 21 does not exist is there.
The thin-walled portion 23b has an etching resistant film 25 exposed on the bottom surface of the second recess 22 and a spin-on-glass film (Spin On Glass film: hereinafter referred to as SOG film) formed on the side facing the first substrate 10. 26).
The etching resistant film 25 has resistance to a solution for etching the second base material 21.
The SOG film 26 is a glass film obtained by applying a liquid spin-on glass agent (SOG agent) to a substrate and baking it. The SOG film 26 can be formed with a small variation by controlling the film thickness.

The etching resistant film 25 and the SOG film 26 are formed so as to extend from the thin portion 23 b and cover one surface of the second substrate 20.
The etching resistant film 25 is made of epoxy resin, amorphous fluorine-based resin or the like with a thickness of about 1 μm, and the SOG film 26 is formed with a thickness of about 30 μm.
As described above, the second substrate 20 includes the diaphragm 23, and the movable portion 23 a is configured to easily move in the thickness direction of the second substrate 20.

A second reflective film 27 and a second drive electrode 28 are formed on the SOG film 26 of the second substrate 20 facing the first substrate 10.
The second reflection film 27 has light reflection characteristics and transmission characteristics, and is provided in a circular shape on the movable portion 23 a so as to face the first reflection film 17. As the material of the second reflective film 27, Ag or an Ag alloy is used similarly to the first reflective film 17. The second reflective film 27 is formed with a thickness of 50 nm, for example. Thus, the first reflective film 17 of the first substrate 10 and the second reflective film 27 of the second substrate 20 constitute a pair of opposing reflective films in the etalon 1. The second reflective film 27 may be composed of a dielectric multilayer film.

  The second drive electrode 28 is provided in the thin portion 23 b facing the first drive electrode 18. The second drive electrode 28 is formed in a ring shape so as to surround the second reflective film 27. In this way, the first drive electrode 18 of the first substrate 10 and the second drive electrode 28 of the second substrate 20 face each other, and the electrostatic actuator 40 in the etalon 1 is configured by both, and the gap dimension between the reflective films is Adjustment is possible.

The second drive electrode 28 is connected to the extraction electrode 28a.
The second drive electrode 28 and the extraction electrode 28a are conductive films, for example, an ITO film. These conductive films may be Cr / Au films having a Cr film as a base and an Au film laminated thereon.
Further, the lead electrode 28a is connected to a connection pad 16b formed at one of the four corners of the first substrate 10 by a conductive adhesive (not shown) such as Ag paste, Electrical continuity with the second substrate 20 is achieved.
A bonding film 29 is formed on the bonding surface of the second substrate 20 with the first substrate 10. Further, the second substrate 20 is provided with a notch 21a at a diagonal corner so that the connection pads 16a and 16b of the first substrate 10 are exposed from the upper surface when bonded to the first substrate 10. It is configured.

  In the etalon 1 described above, when the electrostatic actuator 40 is driven in order to change the gap size between the first reflective film 17 and the second reflective film 27 facing each other, the first drive electrode 18 and the second drive electrode are driven by electrostatic force. 28, the thin portion 23 b of the second substrate 20 is bent, and the movable portion 23 a is displaced so as to approach the first substrate 10. The movable part 23 a is provided with a second reflective film 27, and the gap dimension between the first reflective film 17 and the second reflective film 27 can be adjusted.

  The etalon 5 of the present embodiment is formed such that the distance between the first drive electrode 18 and the second drive electrode 28 is smaller than the distance between the first reflective film 17 and the second reflective film 27. Not limited to this configuration, the distance between the first drive electrode 18 and the second drive electrode 28 may be formed larger than the distance between the first reflective film 17 and the second reflective film 27. With such a configuration, it is possible to suppress a pull-in phenomenon in which a pulling force increases rapidly when the gap dimension between the first drive electrode 18 and the second drive electrode 28 becomes minute.

  Further, as the gap dimension setting means, the configuration in which the gap dimension between the reflecting films can be adjusted by the electrostatic actuator 40 is exemplified. However, for example, an electromagnetic actuator having an electromagnetic coil and a permanent magnet, or expansion / contraction by voltage application is possible. A configuration using a piezoelectric element may also be used.

(Method for producing etalon 1)
Next, a method for manufacturing the etalon 1 will be described.
3 to 7 are manufacturing process diagrams for explaining the manufacturing method of the etalon 1.
First, the manufacturing process of a 1st board | substrate is demonstrated using FIG. 3, FIG.
Both surfaces of the first substrate 11 such as quartz glass are mirror-polished, and then a resist is applied to both surfaces of the first substrate 11 to form a resist film 50 as shown in FIG.
Next, the resist film 50 is patterned in order to make a first recess on one surface of the first base material 11 (FIG. 3B).
Then, the first base material 11 is immersed in a hydrofluoric acid aqueous solution and etched to form a recess 53a (FIG. 3C). Thereafter, the resist film 50 is peeled from the first substrate 11.
Subsequently, a resist is applied to both surfaces of the first base material 11 to form a resist film 50, and patterning is performed to create the second step of the first recess. Then, it is immersed in a hydrofluoric acid aqueous solution and etched to form a recess 53b (FIG. 3D).

Then, as illustrated in FIG. 4A, the resist film 50 is peeled from the first base material 11. In this way, the first recess 12 is formed in the first base material 11.
Next, an ITO film is formed on the entire surface of the first recess 12 made in the first base material 11 by sputtering. And a resist is apply | coated on an ITO film | membrane, the resist patterning of a 1st drive electrode part is performed, and an ITO film | membrane is etched with an acidic solution. Thereafter, the resist film is peeled from the first substrate 11. In this way, as shown in FIG. 4B, the first drive electrode 18 is formed in the first recess 12 of the first base material 11.

Subsequently, an Ag alloy film is formed on the entire surface of the first recess 12 formed in the first base material 11 by sputtering. Then, a resist is applied on the Ag alloy film, resist patterning is performed on the first reflective film portion, and the Ag alloy film is etched with, for example, an aqueous phosphonitrate solution. Thereafter, the resist film is peeled from the first substrate 11. In this way, as shown in FIG. 4C, the first reflective film 17 is formed in the first recess 12 of the first base material 11.
Then, as shown in FIG. 4D, in the first base material 11 on which the first reflective film 17 and the first drive electrode 18 are formed, a metal mask in which the upper surface portion of the support portion 13 is opened is a first base. The bonding film 19 is formed by closely contacting the material 11 and forming a plasma polymerization film by a plasma CVD (Chemical Vapor Deposition) method.
Thus, the 1st board | substrate 10 is formed through said process.

Next, the manufacturing process of a 2nd board | substrate is demonstrated using FIG. 5, FIG.
Both surfaces of the second base material 21 such as quartz glass are mirror-polished, and then, as shown in FIG. 5A, an epoxy resin is applied to the entire surface of one side of the second base material 21 using a spin coater or the like and cured. Thus, the etching resistant film 25 is formed.
Subsequently, an SOG agent is applied on the etching resistant film 25 and baked to form an SOG film 26 (FIG. 5B). The SOG film 26 is formed to have a predetermined thickness by applying the SOG agent a plurality of times.

Next, an etching mask film is formed on both surfaces of the second base material 21 on which the etching resistant film 25 and the SOG film 26 are formed. This etching mask film is formed by forming a Cr film having a thickness of about 50 nm on the base, and forming an Au film having a thickness of about 500 nm thereon.
Then, a resist is applied to both surfaces of the second base material 21 and the resist is patterned to form the second concave portion of the diaphragm on one surface. Thereafter, the Au film is etched with a mixed solution of iodine and potassium iodide, and the Cr film is etched with an aqueous cerium ammonium nitrate solution. Thereafter, the resist is peeled from the second base material 21. In this way, an etching mask 52 as shown in FIG. 5C is formed on the second base material 21.

  Next, the second substrate 21 is immersed in a hydrofluoric acid aqueous solution and etched to form the second recess 22 (FIG. 5D). Here, the etching is performed up to the etching resistant film 25 formed on one surface of the second base material 21, and the etching does not proceed to a greater depth in the thickness direction of the second base material 21. Thus, the etching resistant film 25 functions as an etching stop layer. Then, in the second recess 22, the thickness dimension of the second base material 21 is etched, and the depth is the same as the thickness dimension of the second base material 21.

Then, as shown in FIG. 6A, the etching mask 52 is peeled from the second base material 21. Thus, the diaphragm 23 provided with the movable part 23a and the thin part 23b is formed by forming the 2nd recessed part 22 in the 2nd base material 21. FIG.
Next, an ITO film is formed by sputtering on the entire surface of one side of the second base material 21 on which the SOG film 26 is formed. And a resist is apply | coated on an ITO film | membrane, resist patterning of the 2nd drive electrode part is performed, and an ITO film | membrane is etched with an acidic solution. Thereafter, the resist film is peeled from the second base material 21. In this way, the second drive electrode 28 is formed on the SOG film 26 of the second base material 21 as shown in FIG.

Subsequently, an Ag alloy film is formed on the entire surface of the second substrate 21 on which the second drive electrode 28 is formed by sputtering. Then, a resist is applied on the Ag alloy film, resist patterning is performed on the second reflective film portion, and the Ag alloy film is etched with, for example, an aqueous phosphonitrate solution. Thereafter, the resist film is peeled from the second base material 21. In this way, as shown in FIG. 6C, the second reflective film 27 is formed on the SOG film 26 of the second base material 21.
Then, as shown in FIG. 6D, in the second base material 21 on which the second reflective film 27 and the second drive electrode 28 are formed, a metal mask having an opening at the junction with the first substrate 10 is used. 2 Adhering to the base material 21, a plasma polymerization film is formed by a plasma CVD method to form a bonding film 29.
In this way, the second substrate 20 is formed through the above steps.

Next, the joining process of the 1st board | substrate 10 and the 2nd board | substrate 20 is demonstrated using FIG.
As shown in FIGS. 7A and 7B, O ₂ plasma or UV (Ultraviolet) light is applied to the bonding film 19 of the first substrate 10 and the bonding film 29 of the second substrate 20 formed of a plasma polymerization film. Irradiation gives activation energy. Note that, when activation energy is applied to the bonding films 19 and 29, if activation energy is applied to the first reflection film 17 and the second reflection film 27, damage occurs. The activation energy is applied only to 29.
Then, after applying activation energy to the bonding films 19 and 29, the first substrate 10 and the second substrate 20 are aligned, and as shown in FIG. Bonding of the first substrate 10 and the second substrate 20 is completed.
In this way, the etalon 1 of the present embodiment is manufactured.

  As described above, in the etalon 1 of the present embodiment, the SOG film 26 is provided on the thin portion 23 b of the diaphragm 23 in the second substrate 20. The thin portion 23b is not provided with the second base material 21, and the SOG film 26 has a main thickness. For this reason, the thickness of the thin part 23b can be formed without variation. And the bending of the thin part 23b becomes uniform, the gap dimension between reflection films can be set accurately, and the etalon 1 excellent in spectral accuracy can be provided.

Further, an SOG film 26 is formed on the thin portion 23 b so as to face the first substrate 10, and an etching resistant film 25 is exposed on a surface opposite to the surface facing the first substrate 10.
For this reason, by performing etching from the surface opposite to the surface facing the first substrate 10 of the second base material 21, the etching resistant film 25 functions as an etching stop film, and the diaphragm 23 can be easily formed. Yes, it does not affect the thickness of the thin portion 23b by etching.
[Second Embodiment]

Next, the etalon of the second embodiment will be described.
In the present embodiment, only the configuration of the etching resistant film on the second substrate is different from that of the first embodiment. For this reason, the same reference numerals are given to the first substrate and the description thereof is omitted, and the second substrate will be described in detail.
(Configuration of Etalon 2)
FIG. 8 is a cross-sectional view showing the configuration of the etalon of this embodiment.
As shown in FIG. 8, the etalon 2 includes a first substrate 10 and a second substrate 30.
The first substrate 10 and the second substrate 30 are composed of a translucent first base material 11 and a second base material 31, and the plate-like first base material 11 and the second base material 31 are etched. Is formed.
The etalon 2 is integrally formed by joining the first substrate 10 and the second substrate 30. This bonding is fixed by bonding bonding films 19 and 39 provided at the bonding portions of the first substrate 10 and the second substrate 30.

The second substrate 30 has a diaphragm 33. The diaphragm 33 includes a columnar movable portion 33a centering on the center of the substrate, and a thin portion 33b that holds the movable portion 33a around the substrate and is thinner than the movable portion 33a.
The thin portion 33b has an annular second recess 32 formed by etching the second base material 31 on the surface opposite to the surface facing the first substrate 10. The second recess 32 has a depth of the same dimension as the thickness of the second base material 31, and the second base material 31 is etched in the thickness direction in the thin portion 33 b so that the second base material 31 does not exist. is there.
The thin portion 33 b has an etching resistant film 35 exposed on the bottom surface of the second recess 32 and a spin-on-glass film (SOG film) 36 formed on the side facing the first substrate 10.
The etching resistant film 35 is resistant to a solution for etching the second base material 31.
The SOG film 36 is a glass film obtained by applying a liquid spin-on glass agent to a substrate and firing it. The SOG film 36 can be formed with a small variation in thickness by controlling the film thickness.

The etching resistant film 35 is extended from the thin portion 33b and is formed so as to cover one surface of the second substrate 30, but an opening 35a is provided in the central portion of the movable portion 33a, and the etching resistant film 35 is provided. The film 35 is not formed.
The SOG film 36 is formed to extend from the thin portion 33 b so as to cover one surface of the second substrate 30, and the SOG film is also formed in the opening 35 a of the etching resistant film 35.
The etching resistant film 35 is made of a material that does not transmit light, such as a silicon nitride film with low light transmittance, or a Cr / Au film that does not transmit light, and is formed to a thickness of 1 to 3 μm by sputtering. . The SOG film 36 is formed to a thickness of about 30 μm.

A second reflective film 37 and a second drive electrode 38 are formed on the SOG film 36 of the second substrate 30 facing the first substrate 10.
The second reflection film 37 has light reflection characteristics and transmission characteristics, and is provided in a circular shape on the movable portion 33 a so as to face the first reflection film 17. As the material of the second reflective film 37, Ag or an Ag alloy is used similarly to the first reflective film 17. The second reflective film 37 is formed with a thickness of 50 nm, for example. Thus, the first reflective film 17 of the first substrate 10 and the second reflective film 37 of the second substrate 30 constitute a pair of opposing reflective films in the etalon 2. Note that the second reflective film 37 may be formed of a dielectric multilayer film.

  The second drive electrode 38 is provided in the thin portion 33 b facing the first drive electrode 18. The second drive electrode 38 is formed in a ring shape so as to surround the second reflective film 37. In this way, the first drive electrode 18 of the first substrate 10 and the second drive electrode 38 of the second substrate 30 face each other, and the electrostatic actuator 40 in the etalon 2 is configured by both, and the gap dimension between the reflective films is Adjustment is possible.

  In the etalon 2 described above, when the electrostatic actuator 40 is driven in order to change the gap dimension between the first reflective film 17 and the second reflective film 37 facing each other, the first drive electrode 18 and the second drive electrode are driven by electrostatic force. 38, the thin portion 33b of the second substrate 30 is bent, and the movable portion 33a is displaced so as to approach the first substrate 10. The movable part 33 a is provided with a second reflective film 37, and the gap dimension between the first reflective film 17 and the second reflective film 37 can be adjusted.

(Method of manufacturing etalon 2)
Next, a method for manufacturing the etalon 2 will be described.
9 to 11 are manufacturing process diagrams for explaining the manufacturing method of the etalon 2.
Since the manufacturing process of the first substrate is the same as that of the first embodiment, the description thereof is omitted.
The manufacturing process of the second substrate will be described with reference to FIGS.
Both surfaces of the second substrate 31 such as quartz glass are mirror-polished, and then a Cr / Au film is formed on the entire surface of one surface of the second substrate 31 by sputtering, as shown in FIG. An etching resistant film 35 is formed.
Then, a resist is applied on the etching resistant film 35, and the resist is patterned to form an opening. Thereafter, the Au film is etched with a mixed solution of iodine and potassium iodide, and the Cr film is etched with an aqueous cerium ammonium nitrate solution. Then, by removing the resist, an opening 35a is formed in the etching resistant film 35 as shown in FIG.
Subsequently, an SOG agent is applied on the etching resistant film 35 and baked to form an SOG film 36 (FIG. 9C). The SOG film 36 is formed to have a predetermined thickness by applying the SOG agent a plurality of times.

Next, an etching mask film is formed on both surfaces of the second base material 31 on which the etching resistant film 35 and the SOG film 36 are formed. This etching mask film is formed by forming a Cr film having a thickness of about 50 nm on the base, and forming an Au film having a thickness of about 500 nm thereon.
Then, a resist is applied to both surfaces of the second base material 31, and the resist is patterned in order to make the second concave portion of the diaphragm on one surface. Thereafter, the Au film is etched with a mixed solution of iodine and potassium iodide, and the Cr film is etched with an aqueous cerium ammonium nitrate solution. Thereafter, the resist is peeled from the second base material 31. In this way, an etching mask 52 as shown in FIG.

  Next, the second substrate 31 is immersed in a hydrofluoric acid aqueous solution and etched to form the second recess 32 (FIG. 9E). Here, the etching is performed up to the etching resistant film 35 formed on one surface of the second base material 31, and the etching does not proceed to a greater depth in the thickness direction of the second base material 31. Thus, the etching resistant film 35 functions as an etching stop layer. In the second recess 32, the thickness dimension of the second base material 31 is etched, and the depth is the same as the thickness dimension of the second base material 31.

Then, as shown in FIG. 10A, the etching mask 52 is peeled from the second base material 31. Here, the peeling of the etching mask 52 is performed in the order of a mixed solution of iodine and potassium iodide and a cerium ammonium nitrate aqueous solution in the same manner as in the patterning, whereby the Cr film of the etching resistant film 35 is removed.
Thus, the diaphragm 33 provided with the movable part 33a and the thin part 33b is formed by forming the 2nd recessed part 32 in the 2nd base material 31. As shown in FIG.
Next, an ITO film is formed on the entire surface of one side of the second base material 31 on which the SOG film 36 is formed by sputtering. And a resist is apply | coated on an ITO film | membrane, resist patterning of the 2nd drive electrode part is performed, and an ITO film | membrane is etched with an acidic solution. Thereafter, the resist film is peeled from the second base material 31. In this way, the second drive electrode 38 is formed on the SOG film 36 of the second base material 31 as shown in FIG.

Subsequently, an Ag alloy film is formed on the entire surface of the second base material 31 on which the second drive electrode 38 is formed by sputtering. Then, a resist is applied on the Ag alloy film, resist patterning is performed on the second reflective film portion, and the Ag alloy film is etched with, for example, an aqueous phosphonitrate solution. Thereafter, the resist film is peeled from the second base material 31. In this way, as shown in FIG. 10C, the second reflective film 37 is formed on the SOG film 36 of the second base material 31.
Then, as shown in FIG. 10D, in the second base material 31 on which the second reflective film 37 and the second drive electrode 38 are formed, a metal mask having an opening at the bonding portion with the first substrate 10 is adhered. Then, a plasma polymerization film is formed by the plasma CVD method to form the bonding film 39.
In this way, the second substrate 30 is formed through the above steps.

Next, the joining process of the 1st board | substrate 10 and the 2nd board | substrate 30 is demonstrated using FIG.
As shown in FIGS. 11A and 11B, O ₂ plasma or UV (Ultraviolet) light is applied to the bonding film 19 of the first substrate 10 and the bonding film 39 of the second substrate 30 which are formed of a plasma polymerization film. Irradiation gives activation energy. It should be noted that when activation energy is applied to the bonding films 19 and 39, if activation energy is applied to the first reflective film 17 and the second reflective film 37, damage is generated. Only 39 is activated energy.
Then, after applying activation energy to the bonding films 19 and 39, the first substrate 10 and the second substrate 30 are aligned, and as shown in FIG. Bonding of the first substrate 10 and the second substrate 30 is completed.
In this way, the etalon 2 of the present embodiment is manufactured.

As described above, in the etalon 2 of the present embodiment, the SOG film 36 is provided on the thin portion 33 b of the diaphragm 33 in the second substrate 30. The thin portion 33b is not provided with the second base material 31, and the SOG film 36 has a main thickness. For this reason, the thickness of the thin part 33b can be formed without variation.
And the bending of the thin part 33b becomes uniform, the gap dimension between reflection films can be set with high precision, and the etalon 2 excellent in spectral accuracy can be provided.
A part of the etching resistant film 35 formed on one surface of the second base material 31 of the movable portion 33a is removed. In this structure, even a material that does not transmit light can be used as the etching resistant film 35, and the degree of freedom of design is widened. In addition, a metal material having high adhesion to the second base material 31 can be used, and the reliability of the etalon 2 can be improved.

Furthermore, an SOG film 36 is formed on the thin portion 33 b so as to face the first substrate 10, and an etching resistant film 35 is exposed on a surface opposite to the surface facing the first substrate 10.
For this reason, by performing etching from the surface opposite to the surface facing the first substrate 10 of the second base material 31, the etching resistant film 35 functions as an etching stop film, and the diaphragm 33 can be easily formed. Yes, it does not affect the thickness of the thin portion 33b by etching.
[Third Embodiment]

Next, an optical module and an electronic device using the etalon described in the first and second embodiments will be described. In the third embodiment, a color measurement device that measures the chromaticity of a measurement object will be described as an example.
FIG. 12 is a block diagram showing the configuration of the color measuring device.
The color measurement device 80 includes a light source device 82 that irradiates light to the inspection target A, a color measurement sensor 84 (optical module), and a control device 86 that controls the overall operation of the color measurement device 80.
The color measurement device 80 irradiates the inspection target A with light from the light source device 82, receives the inspection target light reflected from the inspection target A with the color measurement sensor 84, and outputs a detection signal output from the color measurement sensor 84. This is a device for analyzing and measuring the chromaticity of the inspection target light.

The light source device 82 includes a light source 91 and a plurality of lenses 92 (only one is shown in FIG. 12), and emits white light to the inspection target A. In addition, the plurality of lenses 92 may include a collimator lens. In this case, the light source device 82 converts the light emitted from the light source 91 into parallel light by the collimator lens, and performs inspection from a projection lens (not shown). Inject toward A.
In the present embodiment, the colorimetric device 80 including the light source device 82 is illustrated. However, for example, when the inspection target A is a light emitting member, the colorimetric device may be configured without providing the light source device 82.

The color measurement sensor 84 as an optical module includes an etalon (wavelength variable interference filter) 5, a voltage controller 94 that controls the voltage applied to the electrostatic actuator 40 and changes the wavelength of light transmitted through the etalon 5, and the etalon 5. And a light receiving unit 93 (detection unit) that receives the light transmitted through.
The colorimetric sensor 84 includes an optical lens (not shown) that guides the reflected light (inspection target light) reflected by the inspection target A to the etalon 5. The colorimetric sensor 84 splits the inspection target light incident on the optical lens into light of a predetermined wavelength band by the etalon 5, and the split light is received by the light receiving unit 93.
The light receiving unit 93 includes a photoelectric conversion element such as a photodiode as a detection unit, and generates an electrical signal corresponding to the amount of received light. The light receiving unit 93 is connected to the control device 86 and outputs the generated electrical signal to the control device 86 as a light reception signal.

  The voltage control unit 94 controls the voltage applied to the electrostatic actuator 40 based on the control signal input from the control device 86.

The control device 86 controls the overall operation of the color measuring device 80. As the control device 86, for example, a general-purpose personal computer, a portable information terminal, a color measurement dedicated computer, or the like can be used.
The control device 86 includes a light source control unit 95, a colorimetric sensor control unit 97, a colorimetric processing unit 96 (analysis processing unit), and the like.

The light source control unit 95 is connected to the light source device 82. Then, the light source control unit 95 outputs a predetermined control signal to the light source device 82 based on, for example, a user setting input, and causes the light source device 82 to emit white light with a predetermined brightness.
The colorimetric sensor control unit 97 is connected to the colorimetric sensor 84. Then, the colorimetric sensor control unit 97 sets the wavelength of light received by the colorimetric sensor 84 based on, for example, a user's setting input, and performs a colorimetric control signal indicating that the amount of light received at this wavelength is detected. Output to sensor 84. Thus, the voltage control unit 94 of the colorimetric sensor 84 sets the voltage applied to the electrostatic actuator 40 so as to transmit the wavelength of light desired by the user based on the control signal.

  The colorimetric processing unit 96 controls the colorimetric sensor control unit 97 to change the gap dimension between the reflective films of the etalon 5 to change the wavelength of the light transmitted through the etalon 5. In addition, the colorimetric processing unit 96 acquires the amount of light transmitted through the etalon 5 based on the light reception signal input from the light receiving unit 93. Then, the colorimetric processing unit 96 calculates the chromaticity of the light reflected from the inspection target A based on the received light amount of each wavelength obtained as described above.

As described above, the color measurement device 80 as the electronic apparatus and the color measurement sensor 84 as the optical module of the present embodiment can accurately set the gap dimension between the reflective films, and the etalon 5 having excellent spectral accuracy. Therefore, a highly accurate colorimetric sensor can be obtained.
As described above, in the third embodiment, the colorimetric device 80 is exemplified as the electronic device. However, the wavelength variable interference filter, the optical module, and the electronic device can be used in various other fields.
For example, it can be used as a light-based system for detecting the presence of a specific substance. As such a system, for example, a gas detection device such as a vehicle-mounted gas leak detector that detects a specific gas with high sensitivity by adopting a spectroscopic measurement method using an etalon, or a photoacoustic rare gas detector for a breath test Can be illustrated.
[Fourth Embodiment]

  Hereinafter, an example of the gas detection device will be described with reference to the drawings.

FIG. 13 is a cross-sectional view illustrating an example of a gas detection device including an etalon.
FIG. 14 is a block diagram illustrating a configuration of a control system of the gas detection device.
As shown in FIG. 13, the gas detection device 100 includes a sensor chip 110, a flow path 120 including a suction port 120A, a suction flow path 120B, a discharge flow path 120C, and a discharge port 120D, a main body 130, It is configured with.
The main body unit 130 includes a sensor unit cover 131 having an opening through which the flow channel 120 can be attached, a discharge unit 133, a housing 134, an optical unit 135, a filter 136, an etalon (wavelength variable interference filter) 5, and a light receiving element 137 (light receiving element). A control unit 138 that processes a detected signal and controls the detection unit, a power supply unit 139 that supplies power, and the like. The optical unit 135 emits light, and a beam splitter 135B that reflects light incident from the light source 135A toward the sensor chip 110 and transmits light incident from the sensor chip toward the light receiving element 137. And lenses 135C, 135D, and 135E.

As shown in FIG. 14, the gas detection device 100 is provided with an operation panel 140, a display unit 141, a connection unit 142 for interface with the outside, and a power supply unit 139. When the power supply unit 139 is a secondary battery, a connection unit 143 for charging may be provided.
Further, the control unit 138 of the gas detection device 100 includes a signal processing unit 144 configured by a CPU or the like, a light source driver circuit 145 for controlling the light source 135A, a voltage control unit 146 for controlling the etalon 5, and a light receiving element 137. A light receiving circuit 147 that receives a signal from the sensor chip, reads a code of the sensor chip 110, controls a sensor chip detection circuit 149 that receives a signal from a sensor chip detector 148 that detects the presence or absence of the sensor chip 110, and a discharge means 133. A discharge driver circuit 150 is provided.

Next, operation | movement of the gas detection apparatus 100 is demonstrated below.
A sensor chip detector 148 is provided inside the sensor unit cover 131 at the upper part of the main body unit 130, and the sensor chip detector 148 detects the presence or absence of the sensor chip 110. When the signal processing unit 144 detects the detection signal from the sensor chip detector 148, the signal processing unit 144 determines that the sensor chip 110 is attached, and displays a display signal for displaying on the display unit 141 that the detection operation can be performed. put out.

  For example, when the operation panel 140 is operated by the user and an instruction signal to start the detection process is output from the operation panel 140 to the signal processing unit 144, the signal processing unit 144 first sends the signal processing unit 144 to the light source driver circuit 145. A light source activation signal is output to activate the light source 135A. When the light source 135A is driven, laser light having a single wavelength and stable linear polarization is emitted from the light source 135A. The light source 135 </ b> A includes a temperature sensor and a light amount sensor, and the information is output to the signal processing unit 144. When the signal processing unit 144 determines that the light source 135A is operating stably based on the temperature and light quantity input from the light source 135A, the signal processing unit 144 controls the discharge driver circuit 150 to operate the discharge unit 133. Thereby, the gas sample containing the target substance (gas molecule) to be detected is guided from the suction port 120A to the suction channel 120B, the sensor chip 110, the discharge channel 120C, and the discharge port 120D.

The sensor chip 110 is a sensor that incorporates a plurality of metal nanostructures and uses localized surface plasmon resonance. In such a sensor chip 110, an enhanced electric field is formed between the metal nanostructures by laser light, and when gas molecules enter the enhanced electric field, Raman scattered light and Rayleigh scattered light including information on molecular vibrations are generated. Occur.
These Rayleigh scattered light and Raman scattered light enter the filter 136 through the optical unit 135, and the Rayleigh scattered light is separated by the filter 136, and the Raman scattered light enters the etalon 5. Then, the signal processing unit 144 controls the voltage control unit 146 to adjust the voltage applied to the etalon 5 and causes the etalon 5 to split the Raman scattered light corresponding to the gas molecule to be detected. Thereafter, when the dispersed light is received by the light receiving element 137, a light reception signal corresponding to the amount of received light is output to the signal processing unit 144 via the light receiving circuit 147.
The signal processing unit 144 compares the spectrum data of the Raman scattered light corresponding to the gas molecule to be detected obtained as described above and the data stored in the ROM, and determines whether or not the target gas molecule is the target gas molecule. To determine the substance. Further, the signal processing unit 144 displays the result information on the display unit 141 or outputs the result information from the connection unit 142 to the outside.

  13 and 14 exemplify the gas detection device 100 that performs gas detection from the Raman scattered light obtained by separating the Raman scattered light with the etalon 5, but the gas detection device detects absorbance specific to the gas. By doing so, you may use as a gas detection device which specifies gas classification. In this case, a gas sensor that allows gas to flow into the sensor and detects light absorbed by the gas in the incident light is used as the optical module of the present invention. The gas detection device 100 that analyzes and discriminates the gas flowing into the sensor by such a gas sensor is an electronic apparatus of the present invention. Even in such a configuration, a gas component can be detected using the etalon of the present invention.

In addition, the system for detecting the presence of a specific substance is not limited to the detection of the gas as described above, and is a non-invasive measuring device for saccharides by near infrared spectroscopy and non-invasive information on food, living body, minerals, etc. A substance component analyzer such as a measuring device can be exemplified.
[Fifth Embodiment]

  Next, a food analyzer will be described as an example of the substance component analyzer.

FIG. 15 is a block diagram illustrating a configuration of a food analysis apparatus which is an example of an electronic apparatus using the etalon 5.
The food analyzer 200 includes a detector (optical module) 210, a control unit 220, and a display unit 230. The detector 210 detects a light source 211 that emits light, an imaging lens 212 into which light from a measurement object is introduced, an etalon 5 that splits light introduced from the imaging lens 212, and the dispersed light. An imaging unit (light receiving unit) 213.
Further, the control unit 220 controls the light source control unit 221 that controls the turning on / off of the light source 211 and the brightness at the time of lighting, the voltage control unit 222 that controls the etalon 5, and the imaging unit 213. A detection control unit 223 that acquires a spectral image captured by the unit 213, a signal processing unit 224, and a storage unit 225.

  In the food analyzer 200, when the apparatus is driven, the light source 211 is controlled by the light source control unit 221, and the measurement object is irradiated with light from the light source 211. Then, the light reflected by the measurement object enters the etalon 5 through the imaging lens 212. The etalon 5 is applied with a voltage capable of dispersing a desired wavelength under the control of the voltage control unit 222, and the dispersed light is imaged by an imaging unit 213 configured by, for example, a CCD camera or the like. The captured light is accumulated in the storage unit 225 as a spectral image. Further, the signal processing unit 224 controls the voltage control unit 222 to change the voltage value applied to the etalon 5, and acquires a spectral image for each wavelength.

Then, the signal processing unit 224 performs arithmetic processing on the data of each pixel in each image accumulated in the storage unit 225, and obtains a spectrum at each pixel. In addition, the storage unit 225 stores, for example, information related to food components with respect to the spectrum, and the signal processing unit 224 analyzes the obtained spectrum data based on the information related to food stored in the storage unit 225. The food component contained in the detection target and the content thereof are obtained. Moreover, a food calorie, a freshness, etc. are computable from the obtained food component and content. Furthermore, by analyzing the spectral distribution in the image, it is possible to extract a portion of the food to be inspected that has reduced freshness, and to detect foreign substances contained in the food. Can also be implemented.
Then, the signal processing unit 224 performs processing for causing the display unit 230 to display information such as the component and content of the obtained food to be inspected, calories, and freshness.

FIG. 15 shows an example of the food analysis apparatus 200, but it can also be used as a non-invasive measurement apparatus for other information as described above with a substantially similar configuration. For example, it can be used as a biological analyzer for analyzing biological components such as measurement and analysis of body fluid components such as blood. As such a bioanalytical device, for example, a device that detects ethyl alcohol as a device that measures body fluid components such as blood, it can be used as a drunk driving prevention device that detects the drinking state of an automobile driver. . Further, it can also be used as an electronic endoscope system provided with such a biological analyzer.
Furthermore, it can also be used as a mineral analyzer for performing component analysis of minerals.

Furthermore, the variable wavelength interference filter, the optical module, and the electronic apparatus of the present invention can be applied to the following apparatuses.
For example, it is possible to transmit data using light of each wavelength by changing the intensity of light of each wavelength over time. In this case, light of a specific wavelength is dispersed by an etalon provided in the optical module. By receiving light at the light receiving unit, data transmitted by light of a specific wavelength can be extracted, and light data of each wavelength is processed by an electronic device equipped with such an optical module for data extraction. Thus, optical communication can be performed.
[Sixth Embodiment]

Further, as other electronic devices, the present invention can also be applied to a spectroscopic camera, a spectroscopic analyzer, and the like that spectrally divide light with the etalon (wavelength variable interference filter) of the present invention to capture a spectroscopic image. An example of such a spectroscopic camera is an infrared camera incorporating an etalon.
FIG. 16 is a perspective view showing the configuration of the spectroscopic camera. As shown in FIG. 16, the spectroscopic camera 300 includes a camera body 310, an imaging lens unit 320, and an imaging unit 330.
The camera body 310 is a part that is gripped and operated by a user.
The imaging lens unit 320 is provided in the camera body 310 and guides incident image light to the imaging unit 330. The imaging lens unit 320 includes an objective lens 321, an imaging lens 322, and an etalon 5 provided between these lenses.
The imaging unit 330 includes a light receiving element, and images the image light guided by the imaging lens unit 320.
In such a spectroscopic camera 300, a spectral image of light having a desired wavelength can be captured by transmitting light having a wavelength to be imaged by the etalon 5.

Furthermore, the etalon of the present invention may be used as a bandpass filter. For example, among the light in a predetermined wavelength range emitted from the light emitting element, only light in a narrow band centered on a predetermined wavelength is spectrally transmitted. It can also be used as an optical laser device.
Further, the etalon of the present invention may be used as a biometric authentication device, and can also be applied to authentication devices such as blood vessels, fingerprints, retinas, and irises using light in the near infrared region and visible region.

  Furthermore, an optical module and an electronic device can be used as a concentration detection device. In this case, the infrared energy (infrared light) emitted from the substance is separated and analyzed by the etalon, and the analyte concentration in the sample is measured.

  As described above, the variable wavelength interference filter, the optical module, and the electronic apparatus of the present invention can be applied to any device that splits predetermined light from incident light. And since the etalon of this invention can disperse | distribute a some wavelength with one device as mentioned above, the measurement of the spectrum of a some wavelength and the detection with respect to a some component can be implemented accurately. Therefore, compared with the conventional apparatus which takes out a desired wavelength with several devices, size reduction of an optical module or an electronic device can be accelerated | stimulated, for example, it can use suitably for a portable use and a vehicle-mounted use.

  The present invention is not limited to the embodiment described above, and the specific structure and procedure for carrying out the present invention can be appropriately changed to other structures and the like as long as the object of the present invention can be achieved. it can. Many modifications can be made by those skilled in the art within the technical idea of the present invention.

  DESCRIPTION OF SYMBOLS 1, 2, 5 ... Variable wavelength interference filter (etalon), 10 ... 1st board | substrate, 11 ... 1st base material, 12 ... 1st recessed part, 13 ... Support part, 16a, 16b ... Connection pad, 17 ... 1st reflection Membrane, 18 ... first drive electrode, 18a ... extraction electrode, 19 ... bonding film, 20 ... second substrate, 21 ... second substrate, 21a ... notch, 22 ... second recess, 23 ... diaphragm, 23a ... Movable part, 23b ... thin part, 25 ... etching resistant film, 26 ... spin-on-glass film (SOG film), 27 ... second reflection film, 28 ... second drive electrode, 28a ... extraction electrode, 29 ... bonding film, 30 ... 2nd substrate, 31 ... 2nd base material, 32 ... 2nd recessed part, 33 ... Diaphragm, 33a ... Movable part, 33b ... Thin-walled part, 35 ... Etching-resistant film, 35a ... Opening part, 36 ... Spin-on-glass film (SOG film) ), 37 ... second reflective film, 38 ... 2 drive electrodes, 39 ... bonding film, 40 ... electrostatic actuator, 50 ... resist film, 52 ... etching mask, 53a, 53b ... recess, 80 ... colorimetric device as an electronic device, 82 ... light source device, 84 ... optical module As a colorimetric sensor, 86 ... control device, 91 ... light source, 92 ... lens, 93 ... light receiving unit, 94 ... voltage control unit, 95 ... light source control unit, 96 ... colorimetric processing unit, 97 ... colorimetric sensor control unit , 100 ... a gas detection device as an electronic device, 200 ... a food analysis device as an electronic device, 300 ... a spectroscopic camera as an electronic device.

Claims (8)

A first substrate having a translucent first substrate;
A second substrate having a translucent second base material facing the first substrate and having a diaphragm;
A first reflective film provided on a surface of the first substrate facing the second substrate;
A second reflective film provided on the diaphragm of the second substrate and facing the first reflective film via a gap;
Gap dimension setting means for setting the dimension of the gap,
The diaphragm is movable in a direction approaching or moving away from the first reflective film, the movable part where the second reflective film is disposed, and a depth that is the same as the thickness of the second base material that supports the movable part. A thin-walled portion formed with a recess of
A variable wavelength interference filter, wherein a spin-on-glass film is provided on the thin-walled portion. The tunable interference filter according to claim 1,
The second substrate includes the spin-on-glass film on one surface of the second base material, and an etching resistant film having resistance to a solution for etching the second base material,
The thin-walled portion is formed with the spin-on-glass film facing the first substrate, and the etching-resistant film is exposed on a surface opposite to the surface facing the first substrate. Wavelength variable interference filter. The tunable interference filter according to claim 2,
The movable part is formed by laminating the etching resistant film and the spin-on-glass film on one surface of the second base material,
The wavelength tunable interference filter, wherein the etching resistant film is not formed in a part of a portion overlapping the second optical film in a plan view in the thickness direction of the second base material. In the wavelength variable interference filter according to any one of claims 1 to 3,
A first drive electrode provided on a surface of the first substrate facing the second substrate as the gap dimension setting means;
A wavelength tunable interference filter, comprising: a second drive electrode provided on a surface of the second substrate facing the first substrate and facing the first drive electrode. A first substrate having a translucent first substrate;
A second substrate having a translucent second base material facing the first substrate and having a diaphragm;
A first reflective film provided on a surface of the first substrate facing the second substrate;
A second reflective film provided on the diaphragm of the second substrate and facing the first reflective film via a gap;
Gap dimension setting means for setting the dimension of the gap;
A light receiving portion that receives light transmitted through the reflective film,
The diaphragm is movable in a direction approaching or moving away from the first reflective film, the movable part where the second reflective film is disposed, and a depth that is the same as the thickness of the second base material that supports the movable part. A thin-walled portion formed with a recess of
An optical module characterized in that a spin-on glass film is provided on the thin portion. A first substrate having a translucent first substrate;
A second substrate having a translucent second base material facing the first substrate and having a diaphragm;
A first reflective film provided on a surface of the first substrate facing the second substrate;
A second reflective film provided on the diaphragm of the second substrate and facing the first reflective film via a gap;
Gap dimension setting means for setting the dimension of the gap;
A light receiving unit that receives light transmitted through the reflective film;
An analysis processing unit that analyzes the characteristics of the light based on the light received by the light receiving unit,
The diaphragm is movable in a direction approaching or moving away from the first reflective film, the movable part where the second reflective film is disposed, and a depth that is the same as the thickness of the second base material that supports the movable part. A thin-walled portion formed with a recess of
An electronic apparatus, wherein a thin film portion is provided with a spin-on-glass film. Forming an etching mask on the surface of the first substrate;
Etching the etching mask as a mask to form a recess;
Forming a first drive electrode in the recess of the first substrate;
Forming a first reflective film on the first substrate;
Forming an etching resistant film having resistance to an etching solution on one surface of the second substrate;
Forming a spin-on-glass film on the etching resistant film;
Forming an etching mask on the surface of the second substrate opposite to the surface on which the spin-on-glass film is formed;
Etching the etching mask as a mask to form a thin portion; and
Forming a second drive electrode on the second substrate;
Forming a second reflective film on the second substrate;
Bonding the first base material on which the first drive electrode and the first reflective film are formed and the second base material on which the second drive electrode and the second reflective film are formed. A method of manufacturing a wavelength tunable interference filter characterized by the above. In the manufacturing method of the wavelength variable interference filter according to claim 7,
A method of manufacturing a wavelength tunable interference filter, comprising: forming a part of the etching resistant film corresponding to the second reflective film after forming the etching resistant film.

Images