JP6251048B2 - Etalon filter and manufacturing method thereof - Google Patents

Description

The present invention relates to an etalon filter and a method for manufacturing the etalon filter, and more particularly to an etalon filter as an optical device using at least two transparent substrates and a method for manufacturing the etalon filter.

  An optical device configured by combining a plurality of optical members that transmit light to obtain desired characteristics is widely used in various optical devices. In such an optical device, a technique of bonding a plurality of optical members together Is important.

  An etalon filter as an optical device in which a plurality of optical components are combined uses a partial transmission mirror composed of two flat substrates (first and second substrates), and a gap adjusting member (gap member: between them). The distance between the two partial transmission mirrors is determined so that the desired resonator characteristics can be obtained with the metal layer interposed therebetween (see Patent Document 1). The etalon filter having such a structure is assembled by joining the gap member and each partial transmission mirror.

In the etalon filter, optical members may be bonded to each other by bonding (bonding) using an organic adhesive, solder bonding, surface activated bonding, optical contact bonding, or the like.
Of these, surface activated bonding is a technique in which the bonding surface is cleaned using an ion gun in a high vacuum to expose the bonding hands of surface atoms and are directly bonded by overlapping.
The optical contact is a technique for activating and hydrophilizing a bonding surface by irradiation with plasma or excimer laser light, and temporarily bonding by superimposing and then dehydrating and completely bonding by high-temperature treatment.

An example of the etalon filter is shown in FIGS.
6 to 7, the etalon filter 100 is an optical component, and has two flat plate-like first and second substrates 101 and 102 that function as partial transmission mirrors, and are opposed to each other at the center ( The outer peripheral region surrounding the light transmitting region 100A is a substrate bonding region 103 made of a metal layer.

The metal layers 104 </ b> A to 104 </ b> D in the substrate adhesion region 103 are for forming the light transmission region 100 </ b> A that sets the light transmission characteristics of the etalon filter 100, and transmit light L _t having a specific wavelength depending on the thickness thereof. The thickness of the space layer is specified in advance. That is, the metal layers 104A to 104D have a light transmission characteristic setting function for setting the light transmission characteristics of the optical filter (see FIG. 6A).

  In the metal layers 104A to 104D in the substrate adhesion region 103, first, metal films are separately formed for the first and second substrates 101 and 102 by sputtering using a mask. Then, after that, the first and second substrates 101 and 102 are assembled by bonding with the metal film portions of the substrates 101 and 102 to form the metal layers 104A to 104D. Yes.

FIG. 7 shows a schematic perspective view of the etalon filter 100 formed by bonding. Reference numerals 104Aa to 104Da denote first substrate side metal films attached to the first substrate 101 side, and reference numerals 104Ab to 104Db denote second substrate side metal films attached to the second substrate 102 side.
Reference numerals 105a to 105d denote mask holding marks formed during sputtering of the metal layer.

Japanese Patent Laid-Open No. 04-061181

However, the above-described joining technique has the following problems.
First, in the case of using an organic adhesive, there is a problem in reliability due to a decrease in adhesive strength due to a change over time in an environment such as high temperature and high humidity due to the characteristics of the adhesive. In addition, organic adhesives have problems such as thermal expansion and contraction of the adhesive and changes in the optical path length, resulting in unstable characteristics. In addition, it is not easy to make the thickness of the adhesive uniform between products, and there is a problem that variations occur in product characteristics. This variation in thickness is the same in joining using solder.

On the other hand, according to the surface activated bonding and the optical contact, there is almost no decrease in the adhesive strength due to the change over time, and no adhesive is used, so that there is no problem in terms of parallax.
On the other hand, in this surface activated bonding, a high degree of vacuum is required, and in order to bond the activated regions to each other, alignment and the like are necessary, the manufacturing apparatus becomes expensive, and the product cost increases. There is a problem of inviting.

  In addition, the optical contact requires a high temperature treatment of 250 [° C.] or higher, and there is a problem that, when trying to join parts having different thermal expansion coefficients, the heat treatment peels off and cracks occur. Further, when the surface roughness of the joint surface of the optical member becomes rough, there is a problem that the joint strength decreases in the surface activated joint and the optical contact.

  Furthermore, in the case where the light transmitting region 100A is formed by forming the metal layers 104A to 104D by sputtering, the metal layer may not be formed in the light transmitting region 100A by providing a mask and a mask mounting arm at the time of processing. is important.

  In this case, in the example of FIGS. 6 to 7, the mask holding traces 105a to 105d remain toward the corners of the first and second substrates 101 and 102. As the corner region becomes an acute angle and goes to the tip, the bonding strength of the metal layers 104A to 104D becomes weaker. Further, the situation of peeling of the metal film or mixing of foreign matters arises from here, and the long-term reliability is weakened. It was.

  Further, in the state before the contact processing of the respective substrates 101 and 102, the peeling of the metal film in the corner region has hindered and corrected the bonding processing of the first and second substrates 101 and 102. There was an inconvenience that it took time and effort.

For example, the film thickness (bonding film thickness) of the metal layers 104A to 104D is actually very thin, from several nm to several tens of nm, and the width of the mask holding marks 105a to 105d is, for example, about 100 [μm].
Therefore, when the mask holding traces 105a to 105d are on the substrates 101 and 102 and face the corners of the substrates 101 and 102, the combined product (etalon filter) is not joined at the corners. In many cases, the state is easily peeled off. In particular, since external forces are likely to concentrate on corners during tying and cleaning, the metal layers 104A to 104D are more likely to be peeled off and the joint surfaces are more likely to be peeled off, resulting in problems in productivity and environmental resistance. come.

(Object of invention)
The present invention has been made to improve the above-described problems, and in particular, provides an etalon filter that can improve productivity and long-term reliability without causing an increase in product cost, and a method for manufacturing the etalon filter. That is the purpose.

In order to achieve the above object, an etalon filter according to the present invention has a first and second substrates made of a transparent member facing each other and facing each other around a light transmission region previously provided in the center of the facing surface. the surface area and junction region, through the metal layer in the junction region comprises a substrate main body formed by bonding the respective substrates to each other, the wavelength thickness is specific spatial layer of the light-transmitting region in the substrate body In an etalon filter set in advance so as to be able to transmit light Lt,
The metal layer is generated by a technique such as sputtering, and a linear partition that is a trace of a holding arm for holding a mask placed in the light transmission region when the metal layer is generated, It is characterized in that it is formed in a certain region including the position where the distance between the center portion and each edge is shortest from the center portion of the light transmission region toward each edge of each substrate. The composition is taken.

In order to achieve the above object, a method for manufacturing an etalon filter according to the present invention includes a first and a second substrate made of a transparent member facing each other and surrounding a light transmission region provided in advance in the center of the facing surface. together with the opposed surface area and the bonding region comprises a substrate body via a metallic layer in the junction region formed by bonding the respective substrates to each other, the thickness of the space layer of the light-transmitting region in the substrate body in the etalon filter comprising preset so as to transmit light Lt of a specific wavelength,
A substrate forming step in which the first and second substrates are formed of a transparent material containing silicon dioxide, and a coating such as a necessary antireflection film or a reflection film is previously applied to each substrate;
The first and second metallic bonding films for forming the metal layer are formed by sputtering in the peripheral bonding area excluding the central area on the opposing surface side which is the bonding surface of the first and second substrates. Forming a bonding film,
The metallic bonding films of the substrates are brought into contact with each other, and the first and second substrates are joined in an overlapped state, whereby the light transmission region having a predetermined thickness having an optical filter function is formed at the center thereof. Each including a light transmission region forming step to be formed,
Prior to the execution of the bonding film forming step,
In the central region corresponding to the light transmission region of the opposing surface of each of the first and second substrates, a mask for preventing the formation of the metallic bonding film is set in advance.
Next, when the mask holding arm for holding the mask is directed from the central portion of the mask toward the corresponding edge of each of the first and second substrates and the metallic bonding film portion is overlapped, the same position is obtained. The mask holding arm is disposed so as to overlap with each other.

  Since the present invention is configured as described above, according to this, since the arrangement direction of the mask holding arm is set as described above, there is no acute angle region in the outer peripheral portion of the adhesion surface of the metal layer, and thus the product cost is reduced. As a result, the overall bonding strength of each of the first and second substrates, which are optical components, is enhanced and the peeling of the metal layer is effectively suppressed, which increases productivity and long-term reliability. It is possible to provide an unprecedented excellent etalon filter and a method for manufacturing the same that can effectively improve the performance.

It is a figure which shows one Embodiment of the etalon filter concerning this invention, and is a front view which shows a board | substrate main-body part. 1 is a cross-sectional view of the embodiment disclosed in FIG. 1, FIG. 2A is a cross-sectional view taken along line II in FIG. 1, and FIG. 2B is an exploded view of FIG. 2A. FIG. It is explanatory drawing which shows the positional relationship of the 1st, 2nd board | substrate, mask, and mask holding arm in embodiment disclosed in FIG. It is a flowchart which shows the procedure of the assembly process of embodiment disclosed in FIG. FIG. 5A is a diagram illustrating an example in which a plurality (9) of etalon filters in the embodiment disclosed in FIG. 1 are simultaneously processed, and FIG. 5A illustrates nine masks on a relatively large first or second substrate; FIG. 5B is an explanatory view showing a state where the mask holding arm is set, and FIG. 5B is an explanatory view showing a generated state of the first or second metallic bonding film generated by sputtering. FIG. 6A is a diagram illustrating an example of a state of use of a conventional etalon filter. FIG. 6A is an explanatory diagram illustrating a state in which transmitted light is transmitted through a central portion of a substrate body that is a main part of the etalon filter, and FIG. FIG. 7 is a cross-sectional view taken along the line II-II in FIG. It is explanatory drawing which shows the setting state of the 1st or 2nd metallic joining film | membrane and mask holding arm trace in the board | substrate main-body part of the conventional etalon filter disclosed to FIG. 6 (A).

Hereinafter, an embodiment of the present invention will be described with reference to FIGS.
1 to 3, the etalon filter 1 includes first and second substrates 11 and 12 made of a transparent member. Each of the substrates 11 and 12 is opposed to each other and has a facing area around the light transmission area 10A set in the center of the facing surface as a bonding area, and the metal layer 13 is interposed in the bonding area. A substrate body 10 is formed by bonding the substrates 11 and 12 to each other.

Here, the metal layer 13, as in the case of FIG. 6 described above, as the space layer of the light transmissive region 10A of the substrate main body 10 is capable of transmitting light L _t of a specific wavelength, to a predetermined thickness It is set in advance.

  In addition, the metal layer 13 is generated by a thin film generating means including a vacuum film forming method such as sputtering in this embodiment, and is used for a mask placed in the light transmission region 10A when the metal layer 13 is generated. The linear partition portions 15a, 15b, 15c, and 15d that are the traces of the holding arms are directed from the center point P of the light transmission region 10A toward the edges of the substrates 11 and 12, and the center point of the light transmission region 10A. It is formed in a certain region including a position where the distance between P and each edge of each of the substrates 11 and 12 is the shortest.

  Specifically, in FIG. 1, the substrates 11 and 12 are formed in a rectangular shape having the same size, and the light transmission region 10 </ b> A is set in a circular shape and disposed at the center of the substrates 11 and 12. At the same time, mask holding marks (linear partition portions) 15a to 15d are formed in a form substantially orthogonal to the central portion of the outer peripheral edge of each of the substrates 11 and 12.

Here, the mask holding traces (linear partitioning portions) 15a to 15d extending from the center point P of the substrates 11 and 12 toward the center of each edge are, for example, from the center of each edge. The position may be somewhat deviated (an angular position that does not hinder the bonding state).
In other words, the mask holding traces (linear partition portions) 15a to 15d are directed from the center point P of the optical communication region 10A to the end sides of the substrates 11 and 12, and the center point P and each end side. In a certain region including the shortest position of the substrate, for example, in a region including the central portion of each edge and deviating from the center (that is, the corners of the substrates 11 and 12 which are regions in which the bonding state is inhibited by concentration of external force) It suffices if it is provided in the outside area).
The mask holding marks (linear partition portions) 15a to 15d will be specifically described later, but in the present embodiment, the line width is set to 100 [μm] or less.
Thereby, the intrusion (circulation) of disturbance light to the transmitted light Lt is effectively suppressed, and light of a specific wavelength can be transmitted with high accuracy even with the weak transmitted light Lt.

Reference numerals 14A, 14B, 14C, and 14D denote the respective portions of the metal layer 13 partitioned by mask holding marks (linear partition portions) 15a to 15d.
In addition, as shown in FIG. 2B, the metal layer 13 is formed by bonding the first metallic bonding film 13A applied in advance to the bonding region of the first substrate 11 and the bonding region of the second substrate 12. And the second metallic bonding film 13B attached in advance to each other.

Here, as described above, the metal layer 13 formed by bonding the first and second metallic bonding films 13A and 13B to the spatial layer of the light transmission region 10A in the substrate body 10 has a specific wavelength. the way the light L _t may not transmit is previously set to a predetermined thickness.

  At the time of this bonding, an atomic diffusion bonding method is used in which sufficient bonding strength can be obtained even with a thin metal film. As a result, the metal layer 13 having a sufficient bonding strength despite being a thin film is formed and maintained.

Thus, in the present embodiment, as described above, the mask holding traces (linear partitioning portions) 15a to 15d of the mask holding arm used when the mask in the central region is mounted are directed to the end sides of the substrates 11 and 12, respectively. Since the corner regions of the substrates 11 and 12 are uniformly bonded throughout, the high adhesive strength in the metal layer 13 portion with respect to the substrates 11 and 12 can be fully utilized. In this respect, it is possible to effectively avoid the peeling of the metal layer (metal film) or the peeling of the joint surface due to an external force, and an etalon filter having high productivity, long-term reliability, and high environmental resistance can be obtained. .
In addition, it is possible to suppress in advance the occurrence of a problem in which the peeled metal layer becomes a foreign substance and enters the etalon filter.

(About the bonding film constituting the metal layer 13)
Here, between the first and second metallic bonding films 13A and 13B and the first and second substrates 11 and 12 described above, a base metal layer for bonding reinforcement (see FIG. (Not shown). In this embodiment, Ta, Cr, Ti, Ni or the like is used as the base metal layer.
The thickness of each of the first and second metallic bonding films 13A and 13B is set to be three times or more the surface roughness of each of the metallic bonding films 13A and 13B.
As a result, a crack or the like does not occur due to the influence of the surface roughness generated during the formation of the metallic bonding films 13A and 13B, and a metallic bonding film having an appropriate strength is set and maintained.

  Each of the first and second metallic bonding films 13A and 13B is made of an oxide such as Au, Pt, or an alloy containing at least one of these metals as a material, and a metal whose generation free energy is positive. Thus, the thickness dimension important as an optical filter function of the light transmission region 10A is set and maintained with high accuracy.

This will be described in further detail.
As described above, each of the first and second substrates 11 and 12 is made of a transparent material containing silicon dioxide. Each of the substrates 11 and 12 is formed of a quartz plate in this embodiment, but may be a quartz plate or a glass plate.

In the bonding region on the surface of the first substrate 11, as described above, the first metallic bonding for forming one surface of the metal layer 13 by a vacuum film forming method such as sputtering is performed. A film 13A is formed.
As described above, the first metallic bonding film 13A is made of a metal material containing a metal having a positive free energy of formation of oxide at room temperature, such as Au, Pt, and an alloy containing these metals.

  As described above, the first metallic bonding film 13A is formed to a thickness that is three times or more the surface roughness of the formation surface. Here, in the Japanese Industrial Standard, “normal temperature” is set to 20 ° C. ± 15 ° C. (5-35 ° C.). The surface roughness is an arithmetic average roughness.

  Similarly to the case of the first substrate 11 described above, the second metallic bonding film 13B is also applied to the opposing contact surface of the second substrate 12 with the same method and material as the second substrate. 12 is formed in a bonding region in a peripheral portion excluding the central portion.

Here, the first and second metallic bonding films 13A and 13B will be described in more detail.
First, the first metallic bonding film 13 </ b> A forms a resist pattern in the above-described bonding region on the opposite surface side of the first substrate 11. The resist pattern may be formed by a known photolithography technique.

With the resist pattern formed in this manner, the above-described metal material for the bonding film is deposited by a vacuum film forming method. Thereafter, if the resist pattern is removed (lifted off) using an organic solvent or the like, the first metallic bonding film 13A can be selectively formed in the bonding region. In this case, the metal material may be deposited by vacuum evaporation, sputtering, or ion plating.
The second metallic bonding film 13B is also formed in the same manner in the bonding region on the opposite surface side of the second substrate 12 described above.

The first and second metallic bonding films 13A and 13B may be formed as follows.
First, a thin film made of the above-described metal material for the metallic bonding film is formed on the entire surface of the first substrate 11 on the above-described facing side. Also in this case, the metal thin film may be formed by a vacuum film formation method, a sputtering method, or the like. Next, a resist pattern is formed on the formed metal film so as to cover the bonding region and open other regions.

The resist pattern may be formed by a known photolithography technique.
Next, the metal film is selectively etched using the formed resist pattern as a mask. For example, when the metal film is made of Au, the metal film can be selectively etched by wet etching with an etching solution made of iodine, ammonium iodide, water, and ethanol.

Thereby, the first metallic bonding film 13A is selectively formed in the bonding region. Further, when there is a concern about contamination due to adsorption of an organic substance or the like on the bonding surface, it is desirable to clean with heating, UV light, plasma, or the like after the formation of the metallic thin film.
The same applies to the second metallic bonding film 13B.

Here, considering the flatness of the first substrate 11 and the second substrate 12, the first substrate 11 with the first and second metallic bonding films 13 </ b> A and 13 </ b> B facing each other. If only the second substrate 12 is placed on the surface, the contact surfaces of the metallic bonding films 13A and 13B are in partial contact with each other in a dot-like manner, and the bonding state becomes insufficient.
In such a case, a certain amount of load may be applied between the first substrate 11 and the second substrate 12 to ensure a sufficiently strong surface contact state.

  After the first and second metallic bonding films 13A and 13B are formed by the method as described above, as described above, the first metallic bonding film 13A and the second substrate of the first substrate 11 are formed. Twelve second metallic bonding films 13B are brought into contact with each other, whereby the first and second substrates 11 and 12 are integrated with each other through the metal layer 13 and the light transmission region 10A at the center thereof. The main body 10 is formed, and at the same time, the first and second metallic bonding films 13A and 13B are opposed to each other and integrated to form the metal layer 13.

Here, one mechanism for joining the metallic bonding films 13A and 13B will be described.
The metal layer formed by sputtering or the like is a thin film having a microcrystalline structure. By superimposing thin films having a microcrystalline structure, metal atoms are diffused at the bonding interface of the thin films, thereby firmly bonding the two substrates.

That is, if the first metallic bonding film 13A and the second metallic bonding film 13B are bonded and integrated with each other, the first substrate 11 and the second substrate 12 can be firmly bonded. .
For this reason, since the first metallic bonding film 13A and the second metallic bonding film 13B are made of a metal material containing a positive metal as described above, the free generation energy of the oxide at room temperature is, A natural oxide film is not formed on the surface even in the air, and a directly joined state can be easily obtained by bringing them into contact with each other.

  This joining is not limited to the atmosphere, and may be performed in a reduced pressure environment, or may be performed in an atmosphere at or above atmospheric pressure. Further, the bonding environment is not limited to the atmosphere, and may be, for example, nitrogen or an inert gas. The bonding temperature may be room temperature. Moreover, in order to assist the spreading | diffusion of bonding films | membranes, you may ripen as needed.

(Etalon filter manufacturing procedure)
Next, the manufacturing procedure of the etalon filter in the above embodiment will be described with reference to FIG. Here, FIG. 4 illustrates a procedure in the case of simultaneously manufacturing a plurality (9) of etalon filters.

First, in the production of the first and second substrates 11 and 12, thickness polishing, coating such as an antireflection film and a reflection film, etc. are performed in advance to realize a desired optical device (etalon filter). In this case, as the target first and second substrates 11 and 12, for example, wafers K1 and K2 having a size capable of producing a plurality (9) of etalon filters are prepared in advance (FIG. 4: Step S101 / First step (substrate forming step)).
As a result, for example, when nine etalon filters are manufactured, a batch process can be performed, and the manufacturing cost can be reduced.

Next, desired patterning is performed on each of the first and second wafers K1 and K2 (FIG. 4: step S102 / second step).
In this patterning, for each substrate region cut out from each of the wafers K1 and K2, a bonding film (metallic bonding film) is formed by covering the central region (light passage portion / optical path of the substrate) with a metal mask or photoresist. To be prevented. FIG. 5A shows an example of the shape (shaded portion) of the mask M in the case of a metal mask. A frame portion of each of the wafers K1 and K2 indicates an arm fixing region for fixing and holding a mask holding arm that holds the mask M.

  Here, the circular mask M having the same pattern is used for each of the wafers K1 and K2. Symbol r indicates a mask holding arm. Each mask M and mask holding arm r is indicated by hatching in FIG. A metallic bonding film is not formed on the shaded portion.

  As shown in FIG. 5A, the mask holding arm r for holding the circular masks M connects the masks M in a grid pattern, and the edges of the rectangular wafers K1 and K2. It is installed in a form orthogonal to 20A, 20B, 20C, 20D.

Subsequently, using a sputtering apparatus or the like, a base metal such as Ta, Cr, Ti, or Ni is formed on the wafers K1 and K2 to be bonded to improve adhesion. Thereafter, an Au film to be a bonding film is formed (FIG. 4: Step S103 / third step (bonding film forming step)). A hatched portion in FIG. 5B indicates a region where the bonding film is formed.
Here, the film thickness of the base metal is preferably 0.2 [nm] or more in view of adhesion. Further, the thickness of the bonding film is preferably 2 [nm] or more from the bonding strength.

Next, it is taken out from the film forming apparatus, the mask is removed, and then the wafers K1 and K2 are aligned with each other and the process proceeds to the overlaying process (FIG. 4: step S104 / fourth process).
In this case, prior to the overlaying process, contamination such as an organic layer is removed by plasma washing or the like as necessary. In particular, when a mask is formed with a photoresist, it is necessary to remove the remaining resist.
Such treatment may be performed in the air or in a vacuum atmosphere or an inert gas atmosphere as necessary.

  Next, the wafers K1 and K2 are aligned with each other so that the patterns of the optical path portion, the bonding film portion, and the mask holding trace portion in the first and second substrates for forming the light transmission region 10A match. Then, the wafers K1 and K2 are bonded to each other, and thereafter, pressurization is performed so that the bonded surfaces are completely brought into close contact with each other (FIG. 4: Step S105 / fifth step (light transmission region forming step)).

In this case, heating may be applied within a range that does not deteriorate the element in order to promote diffusion between metals. The temperature is preferably from room temperature to 250 [° C.].
In this fifth step, a bonded body (state before dicing processing of nine substrate bodies 10) W in which the first and second substrates shown in FIG. 5B are bonded is completed at the wafer level. The bonded body W shown in FIG. 5B shows a bonded body portion when the wafer K1 on the first substrate side is omitted. In FIG. 5B, the hatched region indicates the metal layer portion. The opposite surface of the wafer K1 has the same configuration.
Moreover, in the same figure, the dotted line C which is a division line shows a dicing position.

  Finally, a product (the etalon filter 1 based on the substrate body 10) shown in FIG. 1 is completed by a process of cutting out individual products by dicing the joined body W (FIG. 4: step S106 / sixth step). .

  Specifically, as shown in FIG. 1, each substrate 11, 12 has a rectangular shape with the same size, and the light transmission region 10 </ b> A is set in a circular shape, so that each substrate body 10. The etalon filter 1 is completed in which mask holding marks (linear partition portions) 15a to 15d are formed in a form orthogonal to the central portion of the outer peripheral edge of the substrate body 10 and disposed at the central portion of the substrate body 10. About this mask holding trace (linear partition part) 15a-15d, it is used as it is or vacuum-sealed as needed.

  According to the present bonding method, since the bonding strength is strong enough to withstand the dicing process (S106), a plurality of products are assembled together with the large wafers K1 and K2, and finally individual products are formed by wafer dicing. A cutting process is possible. Such a process realizes a significant reduction in tact time.

  As described above, this embodiment is configured and mass-produced with the same quality. According to this, since the arrangement direction of the mask holding arm is set as described above, the corner portion of the metal layer 13 is in an acute angle state. Therefore, the overall bonding strength of the first and second substrates, which are optical components, is enhanced and the peeling of the metal layer is effectively suppressed without causing an increase in product cost. As a result, it is possible to provide an unprecedented excellent etalon filter and a method for manufacturing the same that can reliably increase productivity and long-term reliability.

  The present invention is applicable to all optical devices that extract and use light of a specific wavelength.

DESCRIPTION OF SYMBOLS 1 Etalon filter 10 Substrate body 10A Light transmission area 11 First substrate 12 Second substrate 13, 14A, 14B, 14C, 14D Metal layer 13A, 14Aa, 14Ba, 14Ca, 14Da First metallic bonding film 13B, 14Ab , 14Bb, 14Cb, 14Db Second metallic bonding film 15, 15a, 15b, 15c, 15d Linear partition (mask holding trace)

Claims (9)

The first and second substrates made of a transparent member are arranged opposite to each other, and a counter surface area around a light transmission area provided in advance at the center of the counter surface is defined as a bonding area, and a metal layer is interposed in the bonding area. comprising a substrate main body formed by bonding the respective substrates to each other Te, formed by the thickness of the space layer of the light transmitting region is previously set so as to transmit light Lt of a specific wavelength in the substrate main body etalon In the filter,
The metal layer is generated by a technique such as sputtering, and a linear partition that is a trace of a holding arm for holding a mask placed in the light transmission region when the metal layer is generated, An etalon filter formed from a central portion of a light transmission region toward each edge of each substrate and in a certain region including a position where the distance between the central portion and each edge is the shortest. . The etalon filter according to claim 1,
An etalon filter characterized in that each of the first and second substrates has a quadrangular shape and the light transmission region has a circular shape. The etalon filter according to claim 1 or 2,
The etalon filter, wherein the linear partition portion is set at an angular position in which an extending direction of a center line thereof is orthogonal to each end side of each substrate. The etalon filter according to claim 1 or 2,
An etalon filter characterized in that the linear partition portion has a line width of 100 [μm] or less. The etalon filter according to any one of claims 1 to 4,
The metal layer includes a first metallic bonding film previously applied to a bonding region of the first substrate and a second metallic bonding film previously applied to a bonding region of the second substrate. Has been generated,
An etalon filter characterized in that a base metal layer for strengthening bonding is installed in advance between each of the first and second metallic bonding films and each of the first and second substrates. . The etalon filter according to claim 5,
The etalon filter characterized in that the thickness of each of the first and second metallic bonding films is set to a thickness of three times or more the surface roughness of each of the metallic bonding films. The etalon filter according to claim 6,
Each of the first and second metallic bonding films is formed of Au, Pt, or an alloy containing at least one of these metals as a material thereof. The first and second substrates made of a transparent member are arranged to face each other, and the opposite surface region around the light transmission region provided in the center of the opposite surface is a bonding region, and the metal layer is formed in the bonding region. through comprising a substrate main body formed by bonding the respective substrates to each other by, and a thickness of the space layer of the light transmitting region is previously set so as to transmit light Lt of a specific wavelength in the substrate body In the etalon filter,
A substrate forming step in which the first and second substrates are formed of a transparent material containing silicon dioxide, and a coating such as a necessary antireflection film or a reflection film is previously applied to each substrate;
The first and second metallic bonding films for forming the metal layer are formed by sputtering in the peripheral bonding area excluding the central area on the opposing surface side which is the bonding surface of the first and second substrates. Forming a bonding film,
The metallic bonding films of the substrates are brought into contact with each other, and the first and second substrates are joined in an overlapped state, whereby the light transmission region having a predetermined thickness having an optical filter function is formed at the center thereof. Each including a light transmission region forming step to be formed,
Prior to the execution of the bonding film forming step,
In the central region corresponding to the light transmission region of the opposing surface of each of the first and second substrates, a mask for preventing the formation of the metallic bonding film is set in advance.
Next, when the mask holding arm for holding the mask is directed from the central portion of the mask toward the corresponding edge of each of the first and second substrates and the metallic bonding film portion is overlapped, the same position is obtained. A method of manufacturing an etalon filter, comprising arranging and fixing a mask holding arm so as to overlap with each other. In the manufacturing method of the etalon filter according to claim 8,
The method of manufacturing an etalon filter, wherein the mask holding arm is disposed and fixed at the shortest distance from the central region side toward the edge of each of the first and second substrates.

Images