CN100538432C - Wave length variable filter, wave length variable filter module and optical spectrum analyser - Google Patents

Abstract

The object of the present invention is to provide the optical device, wave length variable filter, wave length variable filter module and the optical spectrum analyser that when reducing driving voltage, have superior optical characteristics.Optical device of the present invention (1) possess across at interval with fixation reflex film (35) side of movable part (21) in the face of putting and be arranged on regularly first electrode (33) on the fixed part, with second electrode (43) that facing of fixation reflex film (35) opposition side put and relative fixed portion is provided with regularly that is positioned at movable part (21) across the interval, in first electrode (33) and second electrode (43), one electrode is brought into play function as the detecting electrode that is used for the electrostatic capacitance between detection and the movable part (21), another electrode as be used for and movable part (21) between produce potential difference (PD), between them, produce electrostatic attraction thus, make the drive electrode of the position of movable part (21) and/or posture change and bring into play function.

Description

Wave length variable filter, wave length variable filter module and optical spectrum analyser

Technical field

The present invention relates to optical device, wave length variable filter, wave length variable filter module and optical spectrum analyser.

Background technology

As optical device, the known light wavelength variable filter (Optical Tunable Filter) (for example with reference to patent documentation 1) that for example only separates specific wavelength from light with a plurality of wavelength.

For example the wave length variable filter of patent documentation 1 is tabular, can set along the movable part of its thickness direction displacement into the support substrate almost parallel, be respectively arranged with reflectance coating on the face of the support substrate side of movable part and on the face (opposed faces) of the movable part side of support substrate.

In addition, drive electrode is set on support substrate, and between drive electrode and movable part, produces potential difference (PD), between them, produce electrostatic attraction thus, make the movable part displacement.Displacement by movable part makes two reflectance coatings clearance distance each other variable.And, if the light with a plurality of wavelength to this gap incident, then by interference effect, only penetrates the light of the wavelength corresponding with clearance distance to the outside.

In order suitably to produce such interference effect, need correctly set the distance between movable part and the support substrate, perhaps improve the depth of parallelism of movable part and support substrate.Therefore, a plurality of drive electrodes need be set, and a plurality of detecting electrodes are set with corresponding on support substrate, and, detect movable part and the depth of parallelism of support substrate or the distance between movable part and the support substrate based on the electrostatic capacitance between detecting electrode and the movable part with it.

But, the wave length variable filter of patent documentation 1 is because the face of the movable part side of support substrate is the plane, so must be at grade with detecting electrode and drive electrode setting, if the distance between drive electrode and the detecting electrode is little, it is big that the coupling capacitance that then produces between them becomes, thereby be difficult to correctly carry out described detection.

In addition,, and increase the distance between drive electrode and the detecting electrode, then must reduce the area of drive electrode just because of this, cause and driving voltage uprises if supposed to reduce the coupling capacitance that between drive electrode and detecting electrode, produces.

Patent documentation 1: No. 6747775 instructions of United States Patent (USP)

Summary of the invention

The object of the present invention is to provide the optical device, wave length variable filter, wave length variable filter module and the optical spectrum analyser that when reducing driving voltage, have superior optical characteristics.

Utilize following the present invention to realize such purpose.

The invention provides a kind of optical device, it is characterized in that, possess:

Fixed part with first photo-emission part;

Have across at interval and opposed second photo-emission part of described first photo-emission part, thereby and can described relatively fixed part displacement change the movable part of distance between described first photo-emission part and described second photo-emission part;

Across at interval with the described first photo-emission part side of described movable part in the face of putting, and be arranged on first electrode on the described fixed part regularly;

Across at interval with the described first photo-emission part opposition side of being positioned at of described movable part in the face of putting, and second electrode that is provided with regularly of described relatively fixed part,

In described first electrode and described second electrode, one electrode as be used to detect and described movable part between electrostatic capacitance detecting electrode and bring into play function, another electrode as be used for and described movable part between produce potential difference (PD), between them, produce electrostatic attraction thus, make the drive electrode of the position of described movable part and/or posture change and bring into play function

Light reflection is carried out in reflection between described first photo-emission part and described second photo-emission part, produce and interfere, thereby can be between the outside be penetrated with them the light of the corresponding wavelength of distance.

Thus, can increase distance between drive electrode and the detecting electrode.Consequently, can be reduced in the coupling capacitance that produces between drive electrode and the detecting electrode, detect the electrostatic capacitance between movable part and the detecting electrode accurately, and, make movable part correctly be displaced to desirable position and posture based on this testing result.At this moment, overlay configuration drive electrode and detecting electrode so can realize the large tracts of landization of drive electrode, reduce driving voltage in the plane, and realize the large tracts of landization of detecting electrode improving accuracy of detection.So optical device of the present invention can reduce driving voltage, obtain superior optical characteristics simultaneously.

Optical device of the present invention is preferred, detect the electrostatic capacitance between a described electrode and the described movable part, and based on this testing result, between described another electrode and described movable part, produce potential difference (PD), between them, produce electrostatic attraction thus, make the position and/or the posture change of described movable part.

Thus, during use, movable part more correctly can be formed desirable position and posture.

Optical device of the present invention is preferred, and described first electrode or described second electrode constitute, and alternately switches when bringing into play function when bringing into play function as described detecting electrode and as described drive electrode.

Thus, can make movable part in the first electrode side and this both sides' displacement of the second electrode side.Therefore, can be reduced in the stress that movable part produces, increase the movable range of movable part simultaneously.Consequently, can provide a kind of optical device that can use to the light of the wavelength of wide region.

Optical device of the present invention is preferred, and described first electrode and described second electrode are provided with a plurality of respectively.

Thus, can control the distance between first photo-emission part and second photo-emission part and the depth of parallelism of first photo-emission part and second photo-emission part accurately, make the optical characteristics of optical device superior.

Optical device of the present invention is preferred, and the number of described first electrode is identical with the number of described second electrode, and each first electrode and each second electrode are paired.

Thus, when making the posture change of movable part, can easily set driving voltage.

Optical device of the present invention is preferred, and the shape of described first electrode is the shape similar shapes with described second electrode.

Thus, when making the posture change of movable part, can more easily set driving voltage.

Optical device of the present invention is preferred, and the size of described first electrode is big or small identical with described second electrode.

Thus, when making the posture change of movable part, can further easily set driving voltage.

Optical device of the present invention is preferred, thereby have the support that is used to support described movable part, and link the linking part that described movable part and described support can make the relative described support displacement of described movable part, described movable part, described support and described linking part are integrally formed.

Thus, can make the posture of the relative substrate of movable part more stable.

Optical device of the present invention is preferred, has: first substrate that is formed with described movable part, described support and described linking part; Be fixedly set in second substrate of described support in the one side side of described first substrate; Be fixedly set in the 3rd substrate of described support in the another side side of described first substrate, described first substrate and described second substrate and described the 3rd substrate separately between, be formed with the airtight space of the displacement of allowing described movable part, described second substrate is provided with described first electrode and described first photo-emission part, and described the 3rd substrate is provided with described second electrode.

Thus, can stably drive movable part with the contact between better simply structure blocking movable part and the ambient atmos.

Optical device of the present invention is preferred, is formed with recess at the face of described first substrate side of described second substrate, and the bottom surface of described recess is provided with described first photo-emission part and described first electrode.

Thus, can not be used in the member that liner and so on is set between first substrate and second substrate, reduce the parts number of packages, and can between first substrate and second substrate, form airtight space.

Optical device of the present invention is preferred, second recess that described recess has first recess and forms in the bottom surface of this first recess, described first electrode is arranged on the bottom surface of described first recess in the outside of described second recess, and described first photo-emission part is arranged on the bottom surface of described second recess.

Thus,, increase and produce the light wavelength of interfering, also can reduce the distance between first electrode and the movable part, reduce driving voltage even increase distance between first photo-emission part and second photo-emission part.

Optical device of the present invention is preferred, and described first electrode is set to surround described first photo-emission part.

Thus, can be simply and correctly detect the posture of the relative substrate of movable part.

Optical device of the present invention is preferred, and described first substrate is that main material constitutes with silicon.

Thus, stable driving can be carried out, the more superior optical device of optical characteristics and permanance can be formed.

Optical device of the present invention is preferred, and in described second substrate and described the 3rd substrate is that main material constitutes with glass one of at least.

Thus, light is incided between first photo-emission part and second photo-emission part from the outside via second substrate and/or the 3rd substrate, and light is penetrated to the outside via second substrate and/or the 3rd substrate between first photo-emission part and second photo-emission part.And then, can improve observability, can easily differentiate foreign matter and unfavorable condition such as sneak into to device interior.

Optical device of the present invention is preferred, and in described second substrate and described the 3rd substrate is that main material constitutes with the glass that contains alkali metal ion one of at least.

Thus, be under the main material situation about constituting with silicon at first substrate, can utilize anodic bonding to come to engage simply and securely first substrate, second substrate and/or the 3rd substrate.

Optical device of the present invention is preferred, and described first substrate forms by a Si layer of processing SOI wafer.

Thus, can provide more high-precision movable part, support and linking part more simply.

Optical device of the present invention is preferred, being made of the dielectric multilayer film one of at least in described first photo-emission part and described second photo-emission part.

Thus, the light loss in the time of can preventing the interference of light between first photo-emission part and second photo-emission part improves optical characteristics.

Optical device of the present invention is preferred, under the state that does not produce described potential difference (PD), the distance between described first electrode and the described movable part, and described second electrode and described movable part between distance about equally.

Thus, when position that makes movable part and/or posture change, can easily set driving voltage.

Optical device of the present invention is preferred, and under the state that does not produce described potential difference (PD), described first electrode and described second electrode are symmetrical arranged across described movable part.

Thus, when position that makes movable part and/or posture change, can more easily set driving voltage.

The invention provides a kind of wave length variable filter, it is characterized in that, possess:

Fixed part with first photo-emission part;

Have across at interval and opposed second photo-emission part of described first photo-emission part, thereby and can described relatively fixed part displacement change the movable part of distance between described first photo-emission part and described second photo-emission part;

Across at interval with the described first photo-emission part side of described movable part in the face of putting, and be arranged on first electrode on the described fixed part regularly;

Across at interval with the described first photo-emission part opposition side of being positioned at of described movable part in the face of putting, and second electrode that is provided with regularly of described relatively fixed part,

In described first electrode and described second electrode, one electrode as be used to detect and described movable part between electrostatic capacitance detecting electrode and bring into play function, another electrode as be used for and described movable part between produce potential difference (PD), between them, produce electrostatic attraction thus, make the drive electrode of the position of described movable part and/or posture change and bring into play function

Light reflection is carried out in reflection between described first photo-emission part and described second photo-emission part, produce and interfere, thereby can be between the outside be penetrated with them the light of the corresponding wavelength of distance.

Thus, can increase distance between drive electrode and the detecting electrode.Consequently, can be reduced in the coupling capacitance that produces between drive electrode and the detecting electrode, detect the electrostatic capacitance between movable part and the detecting electrode accurately, and, make movable part correctly be displaced to desirable position and posture based on this testing result.At this moment, overlay configuration drive electrode and detecting electrode so can realize the large tracts of landization of drive electrode, reduce driving voltage in the plane, and realize the large tracts of landization of detecting electrode improving accuracy of detection.So wave length variable filter of the present invention can reduce driving voltage, obtain superior optical characteristics simultaneously.

The invention provides a kind of wave length variable filter module, it is characterized in that, possess:

Fixed part with first photo-emission part;

Have across at interval and opposed second photo-emission part of described first photo-emission part, thereby and can described relatively fixed part displacement change the movable part of distance between described first photo-emission part and described second photo-emission part;

Across at interval with the described first photo-emission part side of described movable part in the face of putting, and be arranged on first electrode on the described fixed part regularly;

Across at interval with the described first photo-emission part opposition side of being positioned at of described movable part in the face of putting, and second electrode that is provided with regularly of described relatively fixed part,

In described first electrode and described second electrode, one electrode as be used to detect and described movable part between electrostatic capacitance detecting electrode and bring into play function, another electrode as be used for and described movable part between produce potential difference (PD), between them, produce electrostatic attraction thus, make the drive electrode of the position of described movable part and/or posture change and bring into play function

Light reflection is carried out in reflection between described first photo-emission part and described second photo-emission part, produce and interfere, thereby can be between the outside be penetrated with them the light of the corresponding wavelength of distance.

Thus, can increase distance between drive electrode and the detecting electrode.Consequently, can be reduced in the coupling capacitance that produces between drive electrode and the detecting electrode, detect the electrostatic capacitance between movable part and the detecting electrode accurately, and, make movable part correctly be displaced to desirable position and posture based on this testing result.At this moment, overlay configuration drive electrode and detecting electrode so can realize the large tracts of landization of drive electrode, reduce driving voltage in the plane, and realize the large tracts of landization of detecting electrode improving accuracy of detection.So wave length variable filter module of the present invention can reduce driving voltage, obtain superior optical characteristics simultaneously.

The invention provides a kind of optical spectrum analyser, it is characterized in that, possess:

Fixed part with first photo-emission part;

Have across at interval and opposed second photo-emission part of described first photo-emission part, thereby and can described relatively fixed part displacement change the movable part of distance between described first photo-emission part and described second photo-emission part;

Across at interval with the described first photo-emission part side of described movable part in the face of putting, and be arranged on first electrode on the described fixed part regularly;

Across at interval with the described first photo-emission part opposition side of being positioned at of described movable part in the face of putting, and second electrode that is provided with regularly of described relatively fixed part,

In described first electrode and described second electrode, one electrode as be used to detect and described movable part between electrostatic capacitance detecting electrode and bring into play function, another electrode as be used for and described movable part between produce potential difference (PD), between them, produce electrostatic attraction thus, make the drive electrode of the position of described movable part and/or posture change and bring into play function

Light reflection is carried out in reflection between described first photo-emission part and described second photo-emission part, produce and interfere, thereby can be between the outside be penetrated with them the light of the corresponding wavelength of distance.

Thus, can increase distance between drive electrode and the detecting electrode.Consequently, can be reduced in the coupling capacitance that produces between drive electrode and the detecting electrode, detect the electrostatic capacitance between movable part and the detecting electrode accurately, and, make movable part correctly be displaced to desirable position and posture based on this testing result.At this moment, overlay configuration drive electrode and detecting electrode so can realize the large tracts of landization of drive electrode, reduce driving voltage in the plane, and realize the large tracts of landization of detecting electrode improving accuracy of detection.So optical spectrum analyser of the present invention can reduce driving voltage, obtain superior optical characteristics simultaneously.

Description of drawings

Fig. 1 is the exploded perspective view of the embodiment of expression optical device of the present invention (wave length variable filter).

Fig. 2 is the vertical view of expression optical device shown in Figure 1.

Fig. 3 is the A-A line sectional view among Fig. 2.

Fig. 4 is used to illustrate the drive electrode of optical device shown in Figure 1 and the figure of detecting electrode.

Fig. 5 is the calcspar of structure of the control system of expression optical device shown in Figure 1.

Fig. 6 is the figure that is used to illustrate the manufacture method of optical device shown in Figure 1.

Fig. 7 is the figure that is used to illustrate the manufacture method of optical device shown in Figure 1.

Fig. 8 is the figure that is used to illustrate the manufacture method of optical device shown in Figure 1.

Fig. 9 is the figure that is used to illustrate the manufacture method of optical device shown in Figure 1.

Figure 10 is the figure that is used to illustrate the manufacture method of optical device shown in Figure 1.

Figure 11 is the figure of the embodiment of expression wave length variable filter module of the present invention.

Figure 12 is the figure of the embodiment of expression optical spectrum analyser of the present invention.

Among the figure: 1-optical device (wave length variable filter), 2-the first substrate, 10-power-on circuit, 12-test section, 13-switching part, 14-control part, 21-movable part, 22-support, 23-linking part, 24-peristome, 25-movable reflectance coating, 26-movable antireflection film, 27,27a, 27b-peristome, 3-the second substrate, 31-the first recess, 32-the second recess, 33,33a, 33b-first electrode, 34-dielectric film, 35-fixation reflex film, 36,36a, 36b-slot part, 37,37a, 37b-the 3rd recess, 38,38a, 38b-extraction electrode, 39-fixedly antireflection films, 4-the three substrate, 41-recess, 43,43a, 43b-second electrode, 44-dielectric film, 42,49-fixedly antireflection films, 47a, 47b-peristome, 3a, 4a-substrate (second substrate), 5,6,6A-mask layer, 51-opening, 7-conductive layer, 8-SOI substrate, 81-basal layer, 82-insulation course, 83-active layer (the-substrate), 9-resist layer, 100-wave length variable filter module, 101,104-optical fiber, 102,103-lens, 200-optical spectrum analyser, 201-light incident section, 202,204-optical system, 203-photo detector, 205-control part, 206-display part, G1-first gap, G2-second gap, G3-third space, L-light.

Embodiment

Below, based on preferred implementation shown in the drawings optical device of the present invention, wave length variable filter, wave length variable filter module and optical spectrum analyser are elaborated.

Fig. 1 is the exploded perspective view of the embodiment of expression optical device of the present invention, Fig. 2 is the vertical view of optical device shown in Figure 1, Fig. 3 is A-A line sectional view of Fig. 2, Fig. 4 is used to illustrate the drive electrode of optical device shown in Figure 1 and the figure of detecting electrode, and Fig. 5 is the calcspar of structure of the control system of expression optical device shown in Figure 1.In addition, in the following description, claim that the upside among Fig. 1 is " on ", downside is a D score, among Fig. 2 and Fig. 4 in paper at the moment side be " on ", the paper inboard is a D score, and the right side is " right side ", and the left side is " left side ", upside among Fig. 3 be " on ", downside is a D score, and the right side is " right side ", and the left side is " left side ".

Optical device 1 shown in Figure 1 by interference effect, only penetrates the wave length variable filter of the light (interference light) corresponding with certain wavelengths in this light wavelength for example for accepting light.In addition, optical device 1 for example also can be used as other optical device use such as photoswitch or optical attenuator.

As Fig. 1 and shown in Figure 3, in such optical device 1, second substrate 3 and the 3rd substrate 4 engage across first substrate 2.Between first substrate 2 and second substrate 3, be formed with first clearance G 1 that is used to make the interference of light and as second clearance G 2 that is used for when reducing first clearance G 1, producing the electrostatic gap of electrostatic attraction.On the other hand, between first substrate 2 and the 3rd substrate 4, form as the third space G3 that is used for when increasing first clearance G 1, producing the electrostatic gap of electrostatic attraction.At this, second clearance G 2 and third space G3 also can be respectively as be used to detect and movable part 21 between electrostatic capacitance detecting electrode and bring into play function.

In such optical device 1,,, has only light ejaculation with the big or small corresponding wavelength of first clearance G 1 then by interference effect if light is to 1 incident of first clearance G.Below, describe each structure of optical device 1 successively in detail.

First substrate 2 has light transmission and electric conductivity, for example is made of silicon.And, thereby first substrate 2 has first clearance G 1 that is used to make between first substrate 2 and second substrate 3 variable movable part 21, support 22 and links them and can make the linking part 23 of movable part 21 relative supports 22 at the above-below direction top offset.They are integrally formed by the peristome 24 that forms different form on first substrate 2.

Movable part 21 is tabular, and in the plane, is positioned at the substantial middle portion of first substrate 2, rounded shape.Such movable part 21 is set to across opposed with second substrate 3 at interval, and can be at the thickness direction top offset.In addition, the shape of movable part 21, size, configuration are not defined in illustrated shape certainly especially.

The thickness of movable part 21 (on average) is suitably selected according to constituent material, purposes etc., is not particularly limited, and preferably about 1～500 μ m, is more preferably about 10～100 μ m.

In addition, on movable part 21, with the face of second substrate, 3 opposed sides (promptly, movable part 21 following) on, as second photo-emission part, be formed with the catoptrical movable reflectance coating of high reflectance (HR coating) 25, with the face of the opposition side of second substrate, 3 opposed sides (promptly, movable part 21 top) on, be formed with the movable antireflection film (AR coating) 26 that suppresses the light reflection.

As shown in Figure 3, movable reflectance coating 25 be used for and the fixation reflex film 35 as first photo-emission part described later between repeatedly reflect the light that incides first clearance G 1 below the optical device 1.As shown in Figure 3, movable antireflection film 26 be used for preventing inciding first clearance G 1 from the below of optical device 1 light on first substrate 2 and the boundary reflection between the ambient atmos below figure.

Movable reflectance coating (dielectric multilayer film) if 25 or movable antireflection film 26 can obtain the optical characteristics that needs, qualification especially, but preferably constitute by the dielectric multilayer film.That is, movable reflectance coating (dielectric multilayer film) 25 or movable antireflection film 26 preferably constitute by alternative stacked high refractive index layer and low-index layer respectively.Thus, the loss of the light in the time of can preventing the interference of light between movable reflectance coating 25 and fixation reflex film 35, thus improve optical characteristics.

As the material that constitutes high refractive index layer, get final product so long as can obtain the material of movable reflectance coating 25 or movable antireflection film 26 needed optical characteristics, do not limit especially, but, can enumerate Ti when in the visible region or during the infrared light region use ₂O, Ta ₂O ₅, niobium oxide etc., in addition, when using, can enumerate Al in the ultraviolet light zone ₂O ₃, HfO ₂, ZrO ₂, ThO ₂Deng.In the present embodiment, because first substrate 2 is made of silicon, so use infrared light in the optical device 1.Therefore, the material as constituting high refractive index layer preferably uses Ti ₂O, Ta ₂O ₅, niobium oxide etc.

As the material that constitutes low-index layer, get final product so long as can obtain the material of movable reflectance coating 25 or movable antireflection film 26 needed optical characteristics, do not limit especially, for example can enumerate MgF ₂, SiO ₂Deng.Particularly, as the constituent material of low-index layer, preferably use with SiO ₂Constituent material for main material.

Constituting the high refractive index layer of movable reflectance coating 25 and movable antireflection film 26 and the number of plies, the thickness optical characteristics as required of low-index layer sets.Usually when constituting reflectance coating by multilayer film, the number of plies that needs in order to obtain its optical characteristics is more than 12 layers, and when constituting antireflection film by multilayer film, the needed number of plies of its optical characteristics is about 4 layers.

If movable reflectance coating 25 has insulativity, then can prevent the short circuit that causes because of movable part 21 and contacting of first electrode 33.That is,, then can prevent the short circuit that causes because of movable part 21 and contacting of first electrode 33 if the face of second substrate, 3 sides of movable part 21 is provided with dielectric film.

In this case,, movable reflectance coating 25 is dielectric film, so can prevent the short circuit that causes because of movable part 21 and contacting of first electrode 33 with simpler structure because holding concurrently.In addition,, movable antireflection film 26 is dielectric film, so can prevent the short circuit that causes because of movable part 21 and contacting of second electrode 43 with simpler structure because also holding concurrently.

Form support 22 and surround such movable part 21, movable part 21 is supported portion's 22 supportings via linking part 23.

Linking part 23 described movable part 21 around along Zhou Fangxiang a plurality of uniformly-spaced to be provided with (being 4 in the present embodiment).This linking part 23 has elasticity (flexible), and thus, movable part 21 and second substrate, 3 almost parallel ground are across at interval, and can be at its thickness direction (up and down) top offset.In addition, as long as the number of linking part 23, position, shape can movable part 21 relative support 22 displacements, be not limited to described content.

In addition, on first substrate 2, be provided with the peristome 27a, the 27b that are used for from outside approaching extraction electrode 38a described later, 38a.This peristome 27a, 27b are in the manufacturing process of optical device 1, also as preventing that the space between first substrate and second substrate from producing and the open function of bringing into play with peristome of the pressure of outside pressure differential.

In the first such substrate 2, preferred movable part 21, support 22 and linking part 23 are integrally formed.Thus, can make the posture of movable part 21 relative second substrates 3 more stable.

At this moment, if movable part 21, support 22 and linking part 23 are respectively that main material constitutes with silicon, then can have more superior optical characteristics and permanance.

Especially if movable part 21, support 22 and linking part 23 form by a Si layer of processing the SOI wafer, then can form more high-precision movable part 21, support 22 and linking part 23 more simply.

The first so relatively substrate 2, joint has second substrate 3 below support 22.

Second substrate 3 has light transmission, on second substrate 3, be formed with second recess 32 that is used for forming first recess 31 of second clearance G 2 between first substrate 2 and second substrate 3 and being used between first substrate 2 and second substrate 3, forming first clearance G 1 in first recess, 31 inboards in its one side side.

Constituent material as the second such substrate 3, as long as it is relevant with employed light wavelength and have a light transmission, then do not limit especially, for example, can enumerate various glass such as soda-lime glass, crystallinity glass, quartz glass, lead glass, potash glass, Pyrex, sodium borosilicate glass, alkali-free glass or silicon etc.

Wherein, as the constituent material of second substrate 3, for example preferably contain the glass of the alkaline metal (mobile ion) of sodium (Na) or potassium (Ka) and so on.Thus, when for example having constituted first substrate 2, can come to engage simply and securely first substrate 2 and second substrate 3 by anodic bonding by silicon.

Especially, when engaging first substrate 2 and second substrate 3 by anodic bonding, the difference between the thermal expansivity of the thermal expansivity of first substrate 2 and second substrate 3 is preferably as far as possible little, particularly, is preferably 50 * 10 ^-7℃ ^-1Below.

Thus, when anodic bonding,, also can be reduced in the stress that produces between first substrate 2 and second substrate 3, prevent the damage of first substrate 2 or second substrate 3 even first substrate 2 and second substrate 3 expose at high temperature.

Thereby, as the constituent material of second substrate 3, preferably use soda-lime glass, potash glass, sodium borosilicate glass etc., for example preferably use the パ イ レ Star Network ス ガ ラ ス (registered trademark) of コ-ニ Application グ corporate system etc.

In addition, the thickness of second substrate 3 (on average) is suitably selected according to constituent material, purposes etc., does not limit especially, but is preferably about 10～2000 μ m, more preferably about 100～1000 μ m.

The profile of first recess 31 is rounded, and it is configured in the position corresponding with described movable part 21, linking part 23 and peristome 24.In addition, on the bottom surface of first recess 31, on the position corresponding with the peripheral part of movable part 21, lamination has circular first electrode 33, dielectric film 34 successively.So the face that is provided with of movable part 21 sides of second substrate 3 is provided with first electrode 33.

First electrode 33 is the approximate circle ring-type as a whole, is made of 2 first electrode 33a, 33b being divided into 2 parts.And as shown in Figure 5, the first electrode 33a, 33b are connected with power-on circuit 10.Thus, can produce potential difference (PD) between first electrode 33 and the movable part 21, reach the electrostatic capacitance that detects between first electrode 33 and the movable part 21.In addition, power-on circuit 10 will be described in detail in the back in detail.

Each the first electrode 33a, 33b are arranged to surround second recess 32.Thus, the electrostatic attraction between each the first electrode 33a, 33b of balance and the movable part 21 simply.Consequently, can make the posture of movable part 21 relative second substrates 3 more stable.

Constituent material as first electrode 33 (separately the first electrode 33a, 33b), as long as have electric conductivity, do not limit especially, for example can enumerate metals such as Cr, Al, Al alloy, Ni, Zn, Ti, disperseed resin that carbon or titanium etc. form, the transparent conductive material of silicon, silicon nitride, ITO and so on such as polysilicon (polysilicon), amorphous silicon, Au etc.

The thickness (on average) of first electrode 33 is so suitably selected according to constituent material, purposes etc., does not limit especially, but is preferably about 0.1～5 μ m.

Dielectric film 34 is the shape identical with first electrode 33, has the function that prevents the short circuit that causes because of movable part 21 and contacting of first electrode 33.

In the space in the first such recess 31,, be formed with second clearance G 2 as the electrostatic gap that is used to drive movable part 21 (driving gap).That is, between the movable part 21 and first electrode 33, be formed with second clearance G 2.

The size of second clearance G 2 (that is, the distance between the movable part 21 and first electrode 33) does not limit especially, but is preferably about 0.5～20 μ m according to suitably selections such as purposes.

The profile of second recess 32 is rounded, and it is roughly concentric with described first recess 31, and has the little external diameter of external diameter than first recess 31 and movable part 21.In addition, on the bottom surface of second recess 32 (faces of movable part 21 sides of second substrate 3), be provided with the fixation reflex film 35 that is sub-circular.

As mentioned above, as shown in Figure 3, fixation reflex film 35 be used for and movable reflectance coating 25 between repeatedly reflect the light that incides first clearance G 1 below the optical device 1.That is, this fixation reflex film 35 can be moving and make the interference of light with the corresponding wavelength of the size (that is the distance between fixation reflex film 35 and the movable reflectance coating 25) of first clearance G 1 with described movable reflectance coating 25 associations.The size of this first clearance G 1 is greater than the size of described second clearance G 2.

The size of first clearance G 1 does not limit especially, but is preferably about 1～100 μ m according to suitably selections such as purposes.

As mentioned above, if the bottom surface of second recess 32 is provided with fixation reflex film 35, then can form and first electrode 33 and movable part 21 between wavelength band range-independence, that can use corresponding to the degree of depth of second recess 32.Therefore, even be set at the wavelength band that can carry out various uses, also can reduce driving voltage.

In addition, can also omit second recess 32.In this case, under the condition of the optical characteristics of not damaging optical device 1, can first electrode be set in the roughly whole zone of the bottom surface of first recess 31, and fixation reflex film 35 is set thereon.Thus, can increase the area of detecting electrode or drive electrode, improve the accuracy of detection of the electrostatic capacitance between movable part 21 and the detecting electrode, perhaps reduce driving voltage.In addition, by constituting the constituent material of fixation reflex film with conductive material, can the fixation reflex film be set in the roughly whole zone of the bottom surface of first recess 31, making movable reflectance coating double is first electrode (detecting electrode or drive electrode).Thus, also can increase the area of detecting electrode or drive electrode, improve the accuracy of detection of the static capacity between movable part 21 and the detecting electrode, perhaps reduce driving voltage.

In addition, in order to draw the described first electrode 33a, 33b to the outside respectively, and on second substrate 3, be formed with the 3rd recess 37a, 37b and be communicated with the 3rd recess 37a, 37b and slot part 36a, the 36b of first recess 31.

The degree of depth of the degree of depth of slot part 36a and the 3rd recess 37a and first recess 31 about equally, their bottom surface is provided with the extraction electrode 38a that is connected with the first electrode 33a.Identical therewith, the degree of depth of slot part 36b and the 3rd recess 37b and the degree of depth of first recess 31 about equally, their bottom surface is provided with the extraction electrode 38b that is connected with the first electrode 33b.

Constituent material as extraction electrode 38 ( extraction electrode 38a, 38b), can use constituent material identical materials with described first electrode 33, as long as have electric conductivity, do not limit especially, for example can enumerate metals such as Cr, Al, Al alloy, Ni, Zn, Ti, disperseed resin that carbon or titanium etc. form, the transparent conductive material of silicon, silicon nitride, ITO and so on such as polysilicon (polysilicon), amorphous silicon, Au etc.

In addition, the thickness of extraction electrode 38 (on average) is suitably selected according to constituent material, purposes etc., does not limit especially, but is preferably about 0.1～5 μ m.And extraction electrode 38a is preferably integrally formed with the described first electrode 33a, and extraction electrode 38b is preferably integrally formed with the described first electrode 33b.

In addition, go up at the another side of second substrate 3 (promptly being formed with the face of opposition side of the face of described first recess, 31 grades) and form fixedly antireflection film 39.

As shown in Figure 3, fixedly antireflection film 39 be used for preventing from the below of optical device 1 light towards 1 irradiation of first clearance G below second substrate 3 and the boundary reflection between the ambient atmos below figure.In addition, fixation reflex the film 35 or fixedly structure of structure and the described movable reflectance coating 25 of antireflection film 39 or movable antireflection film 26 is identical.

The 3rd substrate 4 that engages with first substrate 2 at the opposition side of the second such substrate 3 also has light transmission.And, be formed with the recess 41 that is used between first substrate 2 and the 3rd substrate 4, forming third space G3 in the one side side of the 3rd substrate 4.

So, first substrate 2 and second substrate 3 and the 3rd substrate 4 separately between be formed with the space of the displacement of allowing movable part 21, this space can be formed airtight space.So, can stably drive movable part 21 with the contact between better simply structure blocking movable part 21 and the ambient atmos.In addition, in the present embodiment, the part beyond the movable part of first substrate 2 21, and second substrate 3 and the 3rd substrate 4 constituted fixed part, relative therewith, movable part 21 is movable.

In addition, in the present embodiment, be provided with the fixation reflex film 35 and first electrode 33 as the bottom surface that is formed at the recess on second substrate 3 as described in the present embodiment, so the member of liner and so on can be set between first substrate 2 and second substrate 3, reduce the parts number of packages, and can between first substrate 2 and second substrate 3, form aforesaid airtight space.

As the constituent material of the 3rd such substrate 4, as long as relevant with employed light wavelength and have a permeability, not qualification especially can be used the constituent material identical materials with described second substrate 3.Thereby, used under the situation that comprises alkali-metal glass at constituent material as the 3rd substrate 4, identical with second substrate 3, can engage the 3rd substrate 4 and first substrate 2 by anodic bonding.

If in second substrate 3 and the 3rd substrate 4 is that main material constitutes with glass one of at least, light is incided between fixation reflex film 35 and the movable reflectance coating 25 via second substrate 3 and/or the 3rd substrate 4 from the outside, light is penetrated to the outside via second substrate 3 and/or the 3rd substrate 4 between fixation reflex film 35 and movable reflectance coating 25.

In addition, the thickness of the 3rd substrate 4 (on average) is suitably selected according to constituent material, purposes etc., does not limit especially, but is preferably about 10～2000 μ m, more preferably about 100～1000 μ m.

The profile of recess 41 is rounded, and is identical with described first recess 31, is disposed at the position corresponding with described movable part 21, linking part 23 and peristome 24.In addition, the degree of depth of the degree of depth of recess 41 and external diameter and described first recess 31 and external diameter are about equally.In addition, on the bottom surface of first recess 31, in the position corresponding with the peripheral part of movable part 21, lamination has circular second electrode 43 (second electrode), dielectric film 44 successively.So the face that is provided with of movable part 21 sides of the 3rd substrate 4 is provided with second electrode 43.

Second electrode 43 is the approximate circle ring-type as a whole, and is identical with described first electrode 33, is made of 2 electrode 43a, 43b being divided into 2 parts.And identical with the first electrode 33a, 33b, the second electrode 43a, 43b are connected with power-on circuit 10.Thus, can produce potential difference (PD) between second electrode 43 and the movable part 21, reach the electrostatic capacitance that detects between second electrode 43 and the movable part 21.

If as mentioned above, be provided with in a plurality of first electrodes and second electrode one of at least, then can make the posture change of movable part 21, or detect the posture of movable part 21.When making the posture change of movable part 21, for example, can apply roughly the same voltage to each the first electrode 33a, 34a or each the second electrode 43a, 43b, make movable part 21 displacements to be maintained fixed the depth of parallelism of reflectance coating 35 and movable reflectance coating 25, in addition, can also apply different voltage mutually to each the first electrode 33a, 33b or each the second electrode 43a, 43b, make movable part 21 displacements so that movable reflectance coating 25 relative fixed reflectance coatings 35 tilt.In addition, not only can detect the position of movable part 21, can also detect the posture of movable part 21.

Especially, in the present embodiment, owing to be respectively arranged with a plurality of first electrodes and described second electrode, so can detect the posture of movable part 21 more accurately.In addition, for example can only produce potential difference (PD) at the first electrode 33a and the second electrode 43b, a part that makes movable part 21 is to the 33 side displacements of first electrode, and the other parts that make movable part 21 are to the 43 side displacements of second electrode.Consequently, the posture of movable part 21 is more being changed in the wide region.

In addition, the number of first electrode is identical with the number of second electrode, and each first electrode and each second electrode are paired, so when making the posture change of movable part 21, can easily set driving voltage.In addition, when posture that detects movable part 21 or position, can make the structure of test section 12 described later or handle simple.

In addition, because the shape of first electrode 33 is the shape similar shapes with described second electrode 43, so when making the posture change of movable part 21, can more easily set driving voltage.In addition, when posture that detects movable part 21 or position, can make the structure of test section 12 described later or handle simple.

In addition, the size of first electrode 33 (area) is identical with the size (area) of second electrode 43, so when the posture that makes movable part 21 changes, can further easily set driving voltage.In addition, when posture that detects movable part 21 or position, can make the structure of test section 12 described later or handle simple.

As the constituent material of second electrode 43 (separately the second electrode 43a, 43b), as long as have electric conductivity, do not limit especially, can use constituent material identical materials with described first electrode 33.

The thickness (on average) of second electrode 43 is so suitably selected according to constituent material, purposes etc., does not limit especially, but is preferably about 0.1～5 μ m.

Dielectric film 44 is the shape identical with second electrode 43, has the function that prevents the short circuit that causes because of movable part 21 and contacting of second electrode 43.

In the space in such recess 41,, be formed with third space G3 as the electrostatic gap that is used to drive movable part 21 (driving spacing).That is, between the movable part 21 and second electrode 43, be formed with third space G3.

Do not make between the movable part 21 and first electrode 33, second electrode 43 under the state that produces potential difference (PD), the distance between preferred first electrode 33 and the movable part 21 (second clearance G 2), and second electrode 43 and movable part 21 between distance (third space G3) about equally.Thus, when position that makes movable part 21 and/or posture change, can easily set driving voltage.In addition, when posture that detects movable part 21 or position, can make the structure of test section 12 described later or handle simple.

In this case, under the state that does not produce described potential difference (PD), preferably be symmetrical arranged first electrode 33 and second electrode 43 across movable part 21.Thus, when position that makes movable part 21 and/or posture change, can more easily set driving voltage.In addition, when posture that detects movable part 21 or position, can make the structure of test section 12 described later or handle simple.

The size of third space G3 (that is, the distance between the movable part 21 and second electrode 43) does not limit especially, but is preferably about 0.5～20 μ m according to suitably selections such as purposes.

In addition, on the bottom surface of recess 41, portion is provided with the fixedly antireflection film 42 that is sub-circular in the central.That is, in order to surround fixedly antireflection film 42, and the bottom surface of recess 41 (face is set) is provided with described second electrode 43.

As shown in Figure 3, fixedly antireflection film 42 be used for preventing inciding first clearance G 1 from the below of optical device 1 light below the 3rd substrate 4 and the boundary reflection between the ambient atmos below figure.In addition, fixedly the structure of antireflection film 42 is identical with the structure of described movable antireflection film 26.

In addition, on the 3rd substrate 4, be provided with the peristome 47a, the 47b that are used for from outside approaching described extraction electrode 38a, 38b.In addition, the never illustrated taking-up portion of drawing of described second electrode 43 takes out.

In addition, on the another side of the 3rd substrate 4 (that is, being formed with the face of opposition side of the face of described recess 41 grades), be formed with fixedly antireflection film 49.

As shown in Figure 3, fixedly antireflection film 49 be used for preventing inciding third space G3 from the below of optical device 1 light on the 3rd substrate 4 and the boundary reflection between the ambient atmos below figure.In addition, fixedly the structure of antireflection film 49 is identical with the structure of described movable antireflection film 26.

At this,, further specifically describe power-on circuit 10 based on Fig. 5.

As shown in Figure 5, this power-on circuit 10 have be used for to each electrode 33a, 33b, 43a, 43b apply voltage power supply unit 11, be used to detect the electrostatic capacitance between each electrode 33a, 33b, 43a, 43b and the movable part 21 test section 12, switch the switching part 13 of the connection status between each electrode 33a, 33b, 43a, 43b and power supply unit 11 and the test section 12, control the control part 14 of the driving of power supply unit 11 and switching part 13 based on the testing result of test section 12.

Power supply unit 11 can optionally produce potential difference (PD) arbitrarily between each electrode 33a, 33b, 43a, 43b and movable part 21.That is, optical device 1 can optionally apply voltage to first electrode 33 and second electrode 43, produces potential difference (PD) between first electrode 33 and/or second electrode 43 and movable part 21.Thus, can make movable part 21 become desirable position and posture more reliably.

Test section 12 can detect between each electrode 33a, 33b, 43a, 43b and the movable part 21 independently.Thus, can between each electrode 33a, 33b, 43a, 43b and movable part 21, produce and make movable part 21 become the potential difference (PD) of desirable position and posture.

Switching part 13 can switch the connection status between each electrode 33a, 33b, 43a, 43b and power supply unit 11 and the test section 12.

Control part 14 is controlled the driving of described power supply unit 11 based on the testing result of described test section 12.Thus, can be based on the electrostatic capacitance between each electrode 33a, 33b, 43a, 43b and the movable part 21, between each electrode 33a, 33b, 43a, 43b and movable part 21, optionally produce potential difference (PD) arbitrarily, make movable part 21 become the potential difference (PD) of desirable position and posture with formation.

In addition, control part 14 switches the described connection status of described switching part 13 for example corresponding to the wavelength (first clearance G 1) after setting.

Action (effect) to optical device 1 with such structure describes.

Electrode in described power-on circuit 10 detection first electrodes 33 and second electrode 43 and the electrostatic capacitance between the movable part 21, based on its detection signal (testing result), another electrode in first electrode 33 and second electrode 43 and and moving portion 21 between produce potential difference (PD).

More specifically, during first clearance G 1 of the wavelength after setting when not applying voltage, make first electrode 33 bring into play function, make second electrode 43 bring into play function as detecting electrode as drive electrode.In this case, apply voltage by power-on circuit 10 between the movable part 21 and first electrode 33, the movable part 21 and first electrode 33 are charged mutually be opposite polarity, between generation Coulomb force (electrostatic attraction).

Movable part 21 moves (displacement) to the below because of this Coulomb force towards first electrode 33, and static in the position of the elastic force of linking part 23 and Coulomb force balance.Thus, the size variation of first clearance G 1 and second clearance G 2.At this moment, decide the posture (inclination) of movable part 21 according to the voltage that applies to the first electrode 33a and the balance between the voltage that the first electrode 33b applies.

In addition, during first clearance G 1 of the wavelength after setting when not applying voltage, make first electrode 33 bring into play function, make second electrode 43 bring into play function as drive electrode as detecting electrode.Apply voltage by power-on circuit 10 between the movable part 21 and second electrode 43, the movable part 21 and second electrode 43 are charged mutually be opposite polarity, between generation Coulomb force (electrostatic attraction).

Movable part 21 moves (displacement) to the top because of this Coulomb force towards second electrode 43, and static in the position of the elastic force of linking part 23 and Coulomb force balance.Thus, the size variation of first clearance G 1 and second clearance G 2.At this moment, decide the posture (inclination) of movable part 21 according to the voltage that applies to the second electrode 43a and the balance between the voltage that the second electrode 43b applies.

On the other hand, as shown in Figure 3, if from the below of optical device 1 towards first clearance G, 1 irradiates light L, then light L sees through fixedly antireflection film 39, second substrate 3, fixation reflex film 35, incides first clearance G 1.At this moment, this light L is because the fixedly effect of antireflection film 39 and almost can't harm the lost territory and incide first clearance G 1.

Light after the incident is interreflection (interference) between movable reflectance coating 25 and fixation reflex film 35.At this moment, can utilize movable reflectance coating 25 and fixation reflex film 35 to suppress the loss of light L.

As mentioned above, in the process of light interreflection between movable reflectance coating 25 and fixation reflex film 35, the light of the wavelength of big or small corresponding this interference condition of first clearance G 1 between satisfied and movable reflectance coating 25 and the fixation reflex film 35 is sharply decayed, the light that only keeps the wavelength that has satisfied this interference condition, and finally penetrate from optical device 1.Thereby, by changing the voltage that between movable part 21 and first electrode 33, second electrode 43, applies,, just can change light wavelength through optical device 1 as long as change first clearance G 1 (that is, changing interference condition).

The result of the interference of described smooth L is, see through movable reflectance coating 25, movable part 21, movable antireflection film 26, fixedly antireflection film 42, the 3rd substrate 4, fixing antireflection film 49 with the light (interference light) of the big or small corresponding wavelength of first clearance G 1, to the ejaculation of the top of optical device 1.At this moment, because movable antireflection film 26 and the fixedly effect of antireflection film 42,49, interference light penetrates to the outside of optical device 1 with losing hardly.

In addition, in the present embodiment, the light that incides first clearance G 1 penetrates to the top of optical device 1, but the light that incides first clearance G 1 is penetrated to the below of optical device 1.

In addition, in the present embodiment, optical device 1 makes light from its below incident, but also can make light from top incident relatively.

In the optical device 1 of as above explanation, across at interval with opposed first electrode 33 of face of fixation reflex film 35 sides of movable part 21 with across at interval and opposed second electrode 43 of the face that is arranged in fixation reflex film 35 opposition sides of movable part 21, one electrode as be used to detect and movable part 21 between electrostatic capacitance detecting electrode and bring into play function, another electrode as be used for and movable part 21 between produce potential difference (PD), between them, produce electrostatic attraction thus, make the drive electrode of the position of movable part 21 and/or posture change and bring into play function.

Thus, can increase distance between drive electrode and the detecting electrode.Consequently, can be reduced in the coupling capacitance that produces between drive electrode and the detecting electrode, detect the electrostatic capacitance between movable part 21 and the detecting electrode accurately, and, make movable part 21 correctly be displaced to desirable position and posture based on this testing result.At this moment, overlay configuration drive electrode and detecting electrode so can realize the large tracts of landization of drive electrode, reduce driving voltage in the plane, and realize the large tracts of landization of detecting electrode improving accuracy of detection.So optical device 1 of the present invention can reduce driving voltage, obtains superior optical characteristics simultaneously.

Especially, in the present embodiment, detect the electrostatic capacitance between a described electrode and the movable part 21, and based on this testing result, between described another electrode and movable part 21, produce potential difference (PD), between them, produce electrostatic attraction thus, make the position and/or the posture change of movable part 21, so in use, movable part 21 correctly can be formed desirable position and posture.

In addition, the detection of aforesaid electrostatic capacitance also can be only be carried out when proofreading and correct (calibration), based on predefined conversion table (table) etc., produces potential difference (PD) between described another electrode and movable part 21.In addition, in this case, also all electrode 33a, 33b, 43a, 43b can be used as drive electrode after the correction.

In addition, first electrode 33 and second electrode 43 can be brought into play function as being used to drive the drive electrode of movable part 21 respectively.That is, first electrode 33 or second electrode 43 constitute, and alternately switch when bringing into play function when bringing into play function as detecting electrode and as drive electrode.Thus, can make movable part 21 in first electrode, 33 sides and this both sides' displacement of second electrode, 43 sides.Therefore, can be reduced in the stress that movable part 21 produces, increase the movable range of movable part 21 simultaneously.Consequently, optical device 1 can use the light of the wavelength of wide region.

In addition, the needed driving force of displacement of movable part 21 can be reduced, consequently, driving voltage can be reduced.

The manufacture method of＜optical device 〉

Then, based on Fig. 6 to Figure 10, an example of the manufacture method of optical device 1 is described.

Fig. 6～Figure 10 is the figure that is used to illustrate the manufacturing process of optical device 1.In addition, Fig. 6～Figure 10 represents the section that A-A line section is corresponding with Fig. 2.

The manufacture method of the optical device 1 of present embodiment comprises that the operation of [A] manufacturing second substrate 3, [B] engages the SOI substrate with second substrate 3 operation, operation, [D] that [C] processing SOI substrate is made first substrate 2 make the operation of the 3rd substrate 4, [E] engages the 3rd substrate 4 with first substrate 2 operation.Next coming in order illustrate each operation.

The manufacturing of [A] second substrate 3

—A1—

At first, shown in Fig. 6 (a),, prepare substrate 3a with light transmission as the substrate that is used to form second substrate 3.

As substrate 3a, preferred used thickness evenly, do not have a substrate of deflection or damage.As the constituent material of substrate 3, can use the material of in the explanation of second substrate 3, narrating.As mentioned above, as the constituent material of substrate 3a, for example preferred glass that uses the alkaline metal (mobile ion) that contains sodium (Na) or potassium (K) and so on.Thereby, in the following description, used the situation that contains alkali-metal glass to describe to constituent material as substrate 3a.

—A2—

Then, shown in Fig. 6 (b), on the one side of substrate 3a, form (sheltering) mask layer 5.

As the material that constitutes mask layer 5, for example can enumerate silicon, silicon nitrides etc. such as metals such as Au/Cr, Au/Ti, Pt/Cr, Pt/Ti, polysilicon (polysilicon), amorphous silicon.If the constituent material of mask layer 5 uses silicon, then the connecting airtight property raising of mask layer 5 and substrate 3a.If the constituent material of mask layer 5 uses metal, the observability of then formed mask layer 5 improves.

The thickness of mask layer 5 does not limit especially, is preferably about 0.01～1 μ m, more preferably about 0.09～0.11 μ m.If mask layer 5 is thin excessively, the substrate 3a that then can't adequately protect sometimes, if mask layer is blocked up, then mask layer 5 is peeled off easily because of the internal stress of mask layer 5 becomes sometimes.

Mask layer 5 for example can utilize chemical gaseous phase to become gas phases such as embrane method (CVD method), sputtering method, vapour deposition method to become formation such as embrane method, plating method.

—A3—

Then, shown in Fig. 6 (c), on mask layer 5, form the opening 51 of the flat shape that is corresponding with the flat shape of first recess 31, slot part 36 and the 3rd recess 37.

More specifically, at first, for example use photoetching process, on mask layer 5, apply photoresist, expose, develop, form the Etching mask that has with opening 51 corresponding opening.Then, come etching mask layer 5, removed after the part of mask layer 5, remove Etching mask across this Etching mask.So, on mask layer 5, form opening 51.As this etching, for example can enumerate and utilize CF gas, chlorine is dry ecthing of gas etc. and the wet etching that utilizes fluoric acid+aqueous solution of nitric acid, aqueous alkali etc.

—A4—

Then, by mask layer 5, the one side of etch substrate 3a shown in Fig. 6 (d), forms first recess 31, slot part 36 and the 3rd recess 37.

As this etching, can use dry ecthing method, wet etch method, but preferably use wet etch method.Thus, it is better cylindric formed first recess 31 to be become.In this case, as the etching solution of wet etching, for example preferably using fluoric acid is etching solution etc.In addition, as if alcohol (particularly polyvalent alcohol) such as interpolation glycerine in etching solution, then can make the bottom surface of formed first recess 31 extremely level and smooth.

—A5—

Then, removed after the mask layer 5, used and described operation A2 and the identical method of A3, shown in Fig. 6 (e), formed the mask layer 6 of opening with flat shape corresponding with the flat shape of second recess 32.

The method of removing as mask layer 5, do not limit especially, for example can enumerate the wet etching that utilizes aqueous alkali (for example tetramethylammonium hydroxide aqueous solution etc.), hydrochloric acid+aqueous solution of nitric acid, fluoric acid+aqueous solution of nitric acid etc. and utilize CF gas, chlorine is the dry ecthing etc. of gas etc.

Especially as the method for removing of mask layer 5,, then can remove mask layer 5 effectively with shirtsleeve operation if use wet etching.

—A6—

Then, use the method identical,, shown in Fig. 6 (f), formed after second recess 32, form the mask layer 6A of opening with flat shape corresponding with the flat shape of fixation reflex film 35 across mask layer 6 etch substrate 3a with described operation A4.In addition, the formation of mask layer 6A can be carried out after having removed mask layer 6, also can not carry out when removing mask layer 6.

—A7—

Then, shown in Fig. 7 (a), use mask layer 6A, on the bottom surface of second recess 32, form fixation reflex film 35.

More specifically, by on the bottom surface of second recess 32, replacing aforesaid high refractive index layer of lamination and low-index layer, form fixation reflex film 35.

As the formation method of high refractive index layer and low-index layer, for example preferably use chemical vapor-phase growing method (CVD), physical property chemical vapor-phase growing method (PVD).

—A8—

Then, use and described operation-A5-identical method, shown in Fig. 7 (b), remove mask layer 6.

—A9—

Then, shown in Fig. 7 (c), on the face of the side that is formed with first recess, 31 grades of substrate 4, be made like the conductive layer 7 that is used to form the first electrode 33a, 33b and extraction electrode 38a, 38b etc.

As the formation method of conductive layer 7, for example preferably use chemical vapor-phase growing method (CVD), physical property chemical vapor-phase growing method (PVD).

In addition, the constituent material of conductive layer 7 can use the constituent material of described first electrode 33.

—A10—

Then, shown in Fig. 7 (d), that removes conductive layer 7 does not need part, forms first electrode 33 etc., and forms dielectric film 34 on first electrode 33.And then, on the face of the opposition side of the side that is formed with first recess, 31 grades of substrate 4, form fixedly antireflection film 39.

As the method that does not need part of removing conductive layer 7, can use the method identical with described operation A3.

In addition, as the formation method of first electrode 33, can use the method identical with the formation method of described mask layer 5.

As the fixing formation method of antireflection film 39, can use the method identical with the formation method of described fixation reflex film 35.

As mentioned above, can make second substrate 3.

The joint of [B] the SOI substrate and second substrate 3

—B1—

At first, shown in Fig. 8 (a), prepare SOI (Silicon on Insulator) substrate 8.

The basal layer 81 of this SOI substrate 8 by constituting by Si, by SiO ₂The insulation course 82 that constitutes and the active layer that constitutes by Si 83 these 3 layers lamination and constituting successively.In addition, also SOI substrate 8 be can replace, and SOS (Silicon on Sapphire) substrate, silicon substrate etc. used.

The thickness of SOI substrate 8 does not limit especially, but especially the thickness of active layer 83 is preferably about 10～100 μ m.

—B2—

Then, before the joint of the SOI substrate 8 and second substrate 3, shown in Fig. 8 (b), on the face of active layer 83 sides of SOI substrate 8, form movable reflectance coating 25.

As the formation method of movable reflectance coating 25, can use the method identical with the formation method of described fixation reflex film 35.

—B3—

Then, shown in Fig. 8 (c), engage the SOI substrate 8 and second substrate 3.

As the joint method of the SOI substrate 8 and second substrate 3, for example can use anodic bonding, the joint that utilizes bonding agent, surface activation to engage, used the joint of low-melting glass etc., but preferably use anodic bonding.

Using as the joint method of the SOI substrate 8 and second substrate 3 under the situation of anodic bonding, for example, at first, the negative terminal of not shown direct supply is being connected with second substrate 3, plus end is being connected with the active layer 83 of SOI substrate 8.Then, heat second substrate 3, between the active layer 83 of second substrate 3 and SOI substrate 8, apply voltage simultaneously.By this heating, the alkali-metal positive ion of second substrate 3 for example sodion (Na+) becomes mobile easily.Thus, in the composition surface of second substrate 3 and active layer 83, the composition surface of second substrate, 3 sides is electronegative relatively, the relative positively charged in composition surface of active layer 83 sides.Consequently, by the covalent bond of silicon (Si) and the total electron pair of oxygen (O), and engage second substrate 3 and active layer 83 securely.

The manufacturing of [C] first substrate 2

—C1—

Then, shown in Fig. 9 (a), carry out etching or grinding, remove basal layer 81.

As this engraving method, for example can use wet etching, dry ecthing, but preferably use dry ecthing.No matter under any circumstance, when removing basal layer 81, insulation course 82 all becomes limited part (stopper), because dry ecthing do not use etching solution, so can prevent damage with first electrode, 33 opposed active layers 83 well.Thus, the yield rate in the time of can improving the manufacturing of optical device 1.

—C2—

Then, shown in Fig. 9 (b), carry out etching, remove insulation course 82.

As this engraving method, for example can use wet etching, dry ecthing, but the preferred wet etching that utilizes the etching solution that contains fluoric acid that uses.Thus, can remove insulation course 82 simply, and can make face extremely level and smooth because of removing the active layer 83 that insulation course 82 exposes.

In addition, in described process B 1, replace SOI substrate 8, and using under the situation of the silicon substrate that has the thickness that carries out the required optimum of later operation, also can not carry out operation C1, C1.Thus, can simplify the manufacturing process of optical device 1.

—C3—

Then, shown in Fig. 9 (c), on active layer 83, form movable antireflection film 26.

As the formation method of movable antireflection film 26, can use the method identical with the formation method of described fixation reflex film 35.

—C4—

Then, shown in Fig. 9 (d), form the resist layer 9 that has with peristome 24 and peristome 27 corresponding opening.

As the formation method of resist layer 9, can use the method identical with described operation A2, A3.

—C5—

Then, across resist layer 9, utilize dry ecthing method, especially ICP etching, etch activity layer 83 shown in Fig. 9 (e), has formed after the peristome 27, shown in Fig. 9 (f), forms peristome 24.Thus, form movable part 21, support 22 and linking part 23.

More specifically, if across resist layer 9 dry ecthing active layers 83, then compare with the etching speed of peristome 27, the etching speed of each open area of peristome 24 is slack-off because of micro-loading (microloading) effect, so shown in Fig. 9 (e), the formation of peristome 27 is finished prior to the formation of peristome 24.At this moment, above the 3rd recess 37 that is communicated with first recess 31 via slot part 36, form peristome 27,, eliminated this space and outside pressure differential so the space between the active layer 83 and second substrate 3 is opened to the outside.

At this, micro loading effect is meant that etching speed diminishes along with opening size and the phenomenon that reduces.Thereby, as peristome 27, adopt the fast such size of etching speed of each open area that makes etching speed ratio open portion 24.In the present embodiment, as shown in Figure 1, the shape of peristome 27 is formed square shape, described square shape is with the wide length on one side that is of a size of of the A/F of the Width of each open area of ratio open portion 24.In addition, as the size and the shape of peristome 27, as long as make peristome 27 etching speed ratio open portion 24 each open area etching speed soon, be not limited to described structure, can adopt structure arbitrarily.

If utilize micro loading effect like this, even then be not provided for forming the etching work procedure of peristome 27 separately, also can utilize identical etching work procedure to form peristome 24 and peristome 27, simultaneously according to the order of peristome 27, peristome 24 with its formation, can simplify manufacturing process.

Formed after the peristome 27,, then shown in Fig. 9 (f), connected and form peristome 24, finished the formation of movable part 21, support 22 and linking part 23 if further continue dry ecthing.

At this moment, as mentioned above, because before forming movable part 21 on the active layer 83 (that is, before the formation peristome 24), space and outside pressure differential between the active layer 83 and second substrate 3 have been eliminated in advance, so can prevent linking part 23 breakage along with forming peristome 24.

Especially in this operation, carry out the ICP etching.That is, alternate repetition utilizes etching with the etching of gas with utilize deposited (deposition) formation with the diaphragm of gas, forms movable part 21.

As described etching gas, for example can enumerate SF ₆Deng, in addition,, for example can enumerate C as the described deposited gas of using ₄F ₈Deng.

In this operation, it is described that the use dry etching technology carries out the reasons are as follows of anisotropic etching.

When having used wet etch techniques, along with etched progress, etching solution can be invaded between the active layer 83 and second substrate 3 from the hole that forms at active layer 83, thereby has the trouble of removing first electrode 33 or dielectric film 34.Relative therewith, when having used dry etching technology, there is not such danger.

In addition, when having used isotropic etching, active layer 83 is produced side etching by isotropically etching.Especially if produce side etchings at linking part 23, the weakened of linking part 23 then, permanance deterioration.Relative therewith, when having used anisotropic etching, owing to do not produce side etching, so the control of etching size is superior, the side of linking part 23 also is vertically formed with the plate face of active layer 83, thereby can improve the intensity of linking part 23.

In addition, in the present invention, in this operation, also can use with described different dry ecthing method and form movable part 21, support 22 and linking part 23, in addition, also can use dry ecthing method method in addition to form movable part 21, support 22 and linking part 23.

—C6—

Then, remove resist layer 9, shown in Fig. 9 (g), obtain by engaging the structure that first substrate 2 and second substrate 3 constitute.

[D] makes the operation of the 3rd substrate 4

—D1—

At first, as the substrate that is used to form the 3rd substrate 4, shown in Figure 10 (a), prepare substrate 4a with light transmission.

As substrate 4a, same with described substrate 3a, preferred used thickness evenly, do not have a substrate of deflection or damage.As the constituent material of substrate 4a, same with the constituent material of substrate 3a, can use the material of in the explanation of second substrate 3, narrating.

—D2—

Then, use the identical method of A1～A4 with described operation [A], shown in Figure 10 (b), formation recess 41 and peristome 47a, 47b.

—D3—

Then, use the identical method of A7～A10 with described operation [A], shown in Figure 10 (c), form second electrode 43, dielectric film 44 reaches fixedly antireflection film 42,49.

As mentioned above, can make the 3rd substrate 4.

[E] engages the 3rd substrate 4 with first substrate 2 operation

Then, use the identical method of B3 with described operation [B], be bonded on first substrate 2 of the 3rd substrate 4 that obtains in the described operation [D] and the structure that in described operation [C], obtains.

Thus, shown in Figure 10 (d), obtain optical device 1.

Aforesaid optical device 1 (wave length variable filter) for example can use with Figure 11 or mode shown in Figure 12.

Figure 11 is the figure of the embodiment of expression wave length variable filter module of the present invention, and Figure 12 is the figure of the embodiment of expression optical spectrum analyser of the present invention.

Wave length variable filter module 100 shown in Figure 11 for example is arranged on the light transmission path of optical-fiber network of wavelength division multichannel (WDM) light transmission mode and so on.Such wave length variable filter module 100 possesses optical device 1 as described wave length variable filter, to the optical fiber 101 of this optical device 1 light conducting and lens 102, the light that will penetrate from optical device 1 lens 103 and optical fiber 104 to exterior conductive.

In such wave length variable filter module 100, can make light incide optical device 1 via optical fiber 101 and lens 102 with a plurality of wavelength, and via lens 103 and 104 light that take out desirable wavelength of optical fiber.

Such wave length variable filter module 100 can reduce driving voltage, has superior optical characteristics simultaneously.

In addition, optical spectrum analyser 200 as shown in figure 12 is the device of the spectral characteristic (relation of wavelength and intensity) of the determined light of mensuration.Such optical spectrum analyser 200 possesses the light incident section 201 of the determined light of incident, described optical device 1, the optical system 202 of the determined light of light incident section 201 to optical device 1 conduction will be incided, acceptance is from the photo detector 203 of the light of optical device 1 ejaculation, the optical system 204 that to conduct to photo detector 203 from the light that optical device 1 penetrates, the driving of control optical device 1 and ask the control part 205 of spectral characteristic based on the output of photo detector 203, the display part 206 of the operation result of display control unit 205.

In such optical spectrum analyser 200, the determined light that incides light incident section 201 incides optical device 1 via optical system 202.Then, accepted by photo detector 203 via optical system 204 from the light that optical device 1 penetrates, this light intensity is tried to achieve by control part 205.At this moment, control part 205 changes the interference condition of optical device 1 successively, tries to achieve the light intensity of being accepted by photo detector 203 simultaneously.Then, the information (for example spectral waveform) that control part 205 will be relevant with the light intensity of each wavelength is shown in display part 206.

Such optical spectrum analyser 200 can reduce driving voltage, has superior optical characteristics simultaneously.

More than based on illustrated embodiment optical device of the present invention, wave length variable filter, wave length variable filter module and optical spectrum analyser are illustrated, but the present invention is not limited thereto, and the structure of each several part can be replaced into the structure arbitrarily with identical function.In addition, also can in the present invention, add other works arbitrarily.

In addition, by using described optical device 1, can realize Wavelength variable light source or wavelength variable laser.

In addition, in said embodiment, utilize first recess 31 to form first clearance G 1 or second clearance G 2, but also can not form first recess 31, and, form first clearance G 1 or second clearance G 2 by liner is set between second substrate 3 and first substrate 2.

Claims (21)

1. wave length variable filter is characterized in that possessing:

Fixed part with first photo-emission part;

Have across at interval and opposed second photo-emission part of described first photo-emission part, thereby and can described relatively fixed part displacement change the movable part of distance between described first photo-emission part and described second photo-emission part;

Across at interval with the described first photo-emission part side of described movable part in the face of putting, and be arranged on first electrode on the described fixed part regularly;

Across at interval with the described first photo-emission part opposition side of being positioned at of described movable part in the face of putting, and second electrode that is provided with regularly of described relatively fixed part,

In described first electrode and described second electrode, one electrode is brought into play function as being used to detect the detecting electrode of the electrostatic capacitance between this electrode and the described movable part, another electrode is as being used for producing potential difference (PD) between this another electrode and described movable part, between this another electrode and described movable part, produce electrostatic attraction thus, make the drive electrode of the position of described movable part and/or posture change and bring into play function

Between described first photo-emission part and described second photo-emission part, carry out light reflection repeatedly, produce and interfere, thus can be between the outside be penetrated with them the light of the corresponding wavelength of distance.

2. wave length variable filter according to claim 1, wherein,

Detect the electrostatic capacitance between a described electrode and the described movable part, and, between described another electrode and described movable part, produce potential difference (PD), between them, produce electrostatic attraction thus, make the position and/or the posture change of described movable part based on this testing result.

3. wave length variable filter according to claim 1, wherein,

Described first electrode or described second electrode constitute, and alternately switch when bringing into play function when bringing into play function as described detecting electrode and as described drive electrode.

4. wave length variable filter according to claim 1, wherein,

Described first electrode and described second electrode are provided with a plurality of respectively.

5. wave length variable filter according to claim 4, wherein,

The number of described first electrode is identical with the number of described second electrode, and each first electrode and each second electrode are paired.

6. wave length variable filter according to claim 1, wherein,

The shape of described first electrode is the shape similar shapes with described second electrode.

7. wave length variable filter according to claim 6, wherein,

The size of described first electrode is big or small identical with described second electrode.

8. wave length variable filter according to claim 1, wherein,

Be used to support the support of described movable part and link the linking part that described movable part and described support can make the relative described support displacement of described movable part thereby have, described movable part, described support and described linking part are integrally formed.

9. wave length variable filter according to claim 8, wherein,

Have: first substrate that is formed with described movable part, described support and described linking part; Be fixedly set in second substrate of described support in the one side side of described first substrate; Be fixedly set in the 3rd substrate of described support in the another side side of described first substrate, described first substrate and described second substrate and described the 3rd substrate separately between, be formed with the airtight space of the displacement of allowing described movable part, described second substrate is provided with described first electrode and described first photo-emission part, and described the 3rd substrate is provided with described second electrode.

10. wave length variable filter according to claim 9, wherein,

Face in described first substrate side of described second substrate is formed with recess, and the bottom surface of described recess is provided with described first photo-emission part and described first electrode.

11. wave length variable filter according to claim 10, wherein,

Second recess that described recess has first recess and forms in the bottom surface of this first recess, described first electrode are arranged on the bottom surface of described first recess in the outside of described second recess, and described first photo-emission part is arranged on the bottom surface of described second recess.

12. wave length variable filter according to claim 11, wherein,

Described first electrode is set to surround described first photo-emission part.

13. wave length variable filter according to claim 9, wherein,

Described first substrate is that main material constitutes with silicon.

14. wave length variable filter according to claim 13, wherein,

In described second substrate and described the 3rd substrate is that main material constitutes with glass one of at least.

15. wave length variable filter according to claim 14, wherein,

In described second substrate and described the 3rd substrate is that main material constitutes with the glass that contains alkali metal ion one of at least.

16. wave length variable filter according to claim 9, wherein,

Described first substrate forms by a Si layer of processing SOI wafer.

17. wave length variable filter according to claim 1, wherein,

Constituting one of at least in described first photo-emission part and described second photo-emission part by the dielectric multilayer film.

18. wave length variable filter according to claim 1, wherein,

Under the state that does not produce described potential difference (PD), the distance between the distance between described first electrode and the described movable part and described second electrode and the described movable part about equally.

19. wave length variable filter according to claim 18, wherein,

Under the state that does not produce described potential difference (PD), described first electrode and described second electrode are symmetrical arranged across described movable part.

20. a wave length variable filter module is characterized in that, possesses any described wave length variable filter in the claim 1～19.

21. an optical spectrum analyser is characterized in that, possesses any described wave length variable filter in the claim 1～19.

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