WO1998011460A1

WO1998011460A1 - Production method of waveguide type optical device

Info

Publication number: WO1998011460A1
Application number: PCT/JP1996/002631
Authority: WO
Inventors: Hideaki Takano; Tatemi Ido; Mari Koizumi; Toshinori Hirataka; Hiroaki Inoue; Masakazu Sagawa; Ryoji Inaba
Original assignee: Hitachi, Ltd.
Priority date: 1996-09-13
Filing date: 1996-09-13
Publication date: 1998-03-19
Also published as: JP3644037B2

Abstract

A method of flattening a substrate, in which an organic film is bonded to the substrate having a fiber guide groove, and alternatively the organic film is used also as a lower cladding of an optical waveguide disposed on the film. As the process step for flattening the substrate having the fiber guide groove, this easy method of bonding an organic film facilitates the connection of optical fibers by passive alignment.

Description

Specification

Manufacturing method of waveguide type optical element

Technical field

The present invention relates to a waveguide type optical element used for optical communication, and more particularly, to an optical coupling between an optical waveguide unit made of an organic material and an optical component having a function of injecting or emitting light to or from the optical waveguide unit. For easily realizing the above.

Background art

In optical communications, signals propagate through optical fibers. Therefore, in the waveguide type optical element for controlling an optical signal, the input or output interface needs to be an optical fiber. That is, it is necessary to mount the waveguide type optical element and the optical fiber. There are almost no exceptions in currently marketed waveguide-type optical elements, and the above mounting is performed by a method called active alignment.

As an example of the active alignment method, a case of a semiconductor laser will be described. First, a semiconductor laser is fixed to a table, and a current is applied to emit light. Next, an optical fiber serving as an input or output interface is brought close to the end face of the semiconductor laser. The light intensity of the light emitted from the semiconductor laser, which is incident on the optical fiber, is monitored, and the position of the optical fiber is finely adjusted forward, backward, left, right, up and down so that the light intensity is maximized. The agent is poured in to fix the position of the optical fiber.

Another example of an active alignment method is a light bra. The optical power puller is an optical component that splits the light energy passing through one optical fiber into two or more optical fibers. Typically, it consists of a waveguide that is Y-shaped in the light propagation direction. The procedure of the optical power blur is the same as that of the semiconductor laser, except that the optical power blur does not emit light. That is, it is a passive element. Therefore, first, one optical fiber is moved closer to the waveguide so that light enters the waveguide, and two optical fibers are moved closer to the output side. The intensity of the light entering the two optical fibers on the emission side is monitored, and the positions of a total of three optical fibers, including the one on the incident side, as well as the two optical fibers, are located in front, back, left and right. The light intensity is maximized while finely adjusting it up and down, and the adhesive is poured into the optical fiber. Fix the position.

On the other hand, recently, a method called passive alignment has been studied. This method refers to a method in which the optical fiber and the waveguide are fixed only by simple alignment. In other words, instead of causing the element itself to emit light or directing light, as in the case of active alignment, it is a method of fixing only the mutual positional relationship in the structure.

An example of a passive alignment method will be given. First, a V-groove is formed in advance on the Si substrate by anisotropic etching so that the position of the optical fiber can be determined precisely, and this is used as a fiber guide groove. However, since the fiber guide groove has a depth of several tens of microns, even if an optical waveguide is to be provided as it is, most of the optical waveguide material flows into the fiber guide groove, and a precise light guide is provided near the groove. Waveguide cannot be created. Therefore, the substrate having the fiber guide groove is flattened by the following method. That is, first, a Si02 film is formed on another Si substrate surface by thermal oxidation, the Si02 film side is superimposed on the substrate surface provided with the fiber guide groove, and a high-frequency electric field is applied to bond the two substrates. Fit together. Subsequently, a heat treatment at a temperature of about 100 ° C. is performed to increase the adhesive strength. Thereafter, the Si substrate on the side provided with the thermal oxide film is ground, and the thickness of the Si substrate is reduced to the thickness of the thermal oxide film. After that, the remaining Si on the Si substrate side is immersed in the selective etchant to completely dissolve it, and the surface is planarized by allowing Si02 to appear on the surface. After planarization, an organic optical waveguide is provided using a normal process, and the organic optical waveguide and Si 02 in the groove portion are removed by reactive ion etching to expose the groove. An optical fiber is inserted into the groove and solidified with the adhesive as it is to complete the optical device. (Tabuchi et al., 1993 IEICE Spring Conference C-279, and Tabuchi et al., "Integration of optical hybrids Planarization of V-grooved Si substrate ”, IEICE Technical Report, 0PE-94-62 (1994-09).

However, in the active alignment of the conventional method, the optical element itself is not particularly devised. Therefore, the optical element itself can be easily manufactured, but there is a problem that it takes time to assemble the optical element with the optical fiber. That is, when fine adjustment of the position of a plurality of optical fibers is required, as in the case of the optical power blur shown in another example of the above conventional method, there is a problem that the assembling time significantly increases. For example, split〗 signal light into two If we call a Y-branch element with a function of 1: 2 force, the difficulty of mounting the above optical fiber becomes more severe as the number of input / output devices increases. With a 1:16 force bra, it is almost impossible to make a fine adjustment of the position of a total of 17 optical fibers. For this reason, from 1: 2 force blur to 1:16, there is a problem that the output variation increases and the device characteristics are degraded, and the cost of the optical device becomes high.

On the other hand, in the passive alignment of the conventional method, the mounting with the optical fiber is easy, and the assembly time in the active alignment does not increase remarkably; the substrate having the fiber guide groove is flattened. It has not been put into practical use because it takes time for the process of conversion. That is, the Si substrate on the side where the thermal oxide film is provided is ground, the thickness of the Si substrate is reduced to about the thickness of the thermal oxide film, and the remaining Si on the Si substrate side is immersed in a selective etchant. It takes a long time to completely dissolve and make the Si02 appear on the surface, which makes it difficult to implement optical fiber mounting by passive alignment.

Disclosure of the invention

Therefore, an object of the present invention is to provide a method for simplifying a step of flattening a substrate having a fiber guide groove, and to realize easy optical fiber mounting by passive alignment.

It is another object of the present invention to provide means for simplifying not only the above-described flattening step but also the step of manufacturing an organic optical waveguide provided after the flattening step. In order to achieve the object of the present invention, a method is proposed in which a film made of an organic material is adhered to a substrate having a fiber guide groove, thereby making the surface of the substrate easier and flatter than before. I do.

In order to achieve another object of the present invention, a method is proposed in which a film made of the organic material is also used as a lower clad of an optical waveguide provided on the film.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is an external perspective view showing one embodiment of the present invention. FIG. 2 is a detailed explanatory view of a manufacturing method according to an embodiment of the present invention.

3 to 8 are explanatory views of another manufacturing method according to the embodiment of the present invention.

9 to 12 are explanatory diagrams of another embodiment according to the present invention.

FIG. 13 is an explanatory diagram of another manufacturing method according to one embodiment of the present invention.

FIG. 14 and FIG. 15 are explanatory diagrams of another embodiment according to the present invention. BEST MODE FOR CARRYING OUT THE INVENTION

(Example 1)

FIG. 1 is an external perspective view showing an embodiment of the present invention. First, the components of the present invention and the outline of the manufacturing method are shown, and then the detailed manufacturing method is described.

The present invention includes a substrate 1, an optical fiber guide groove 2 provided on the surface of the substrate, a polyimide film 3, an organic optical waveguide 4, and an optical fiber 6.

In the present invention, by bonding the polyimide film 3 to the surface of the substrate 1, the optical fiber guide groove 2 provided on the surface of the substrate 1 can be flattened much more easily than in the past. Once planarized by this method, it is easy to provide the organic optical waveguide 4 using a normal process. Thereafter, the removed portion 5 indicated by hatching is removed, the optical fiber 6 is inserted into the optical fiber guide groove 2, and the optical fiber 6 is solidified with an adhesive to complete the waveguide type optical element.

FIG. 2 illustrates the production method of the present invention in more detail.

FIG. 2 (a) shows a process T for attaching the film of the present invention.

The thickness of the Si substrate 10 is 1 mm. V-grooves 20 are formed on the surface of the Si substrate 10 as optical fiber guide grooves. The size of the V-groove 20 is such that when a single-mode optical fiber having an outer diameter of 125 μm fits into this V-groove 20, the height of the core of the optical fiber from the substrate surface becomes the organic optical waveguide. The height of the V-groove 20 is about〗 20 microns, and the depth is about 60 microns. The length of the V-groove 20 was 4 mm so that the optical fiber could be sufficiently supported.

The method of forming the V-groove 20 is well known, but will be briefly described here. Base A film made of an inorganic material is formed on the plate surface by a CVD method or the like, a rectangular hole is formed by a usual photoresist process, and only the inorganic material in the hole is selectively etched to produce a mask. Next, by immersing in a K0H solution, which is an anisotropic etchant of Si, only the surface of the Si substrate where holes are opened is etched into a V-groove type.

If the organic waveguide material is applied on the Si substrate 10 with the V-groove 20 by a normal spin coating method, most of the material flows into the V-groove 20, and thus the vicinity of the V-groove 20 It is extremely difficult to produce an optical waveguide parallel to the substrate surface in the above. This is because the size of the core of the organic waveguide is about 10 microns, whereas the width and depth of the V-groove 20 are one digit larger.

Therefore, in the present invention, a polyimide film 30 having a thickness of 10 μm is attached to the Si substrate 10 on which the V-groove 2 is formed by using an adhesive. Thereby, the V-groove 2 can be easily flattened as compared with the conventional method.

FIG. 2 (b) shows a step of providing an organic waveguide on a flattened substrate.

As an example of an organic waveguide, use here is made of fluorinated polyimide with a relative refractive index difference of 0.3% between the core and clad on a flattened substrate, and the core is 8 microns in thickness and width. A single-mode organic optical waveguide with a wavelength of 1.55 microns is provided. (Polyimide is one of the heat-resistant polymer materials, has a proven track record in electronic devices, etc., and is one of the reliable materials. Polyimide is a near-infrared light used in optical communications. Fluorinated polyimide hardly absorbs near-infrared light by fluorinating part of the molecular structure of polyimid Kobayashi et al., “Single Mode Polyimide Optical Waveguide”, IEICE Technical Report, 0ME-95-52, 0PE95-93 (1995) See -10).)

Although the method for producing the organic optical waveguide is well known, it will be described here because the material limitation condition of the organic film of the present invention is involved. First, a lower cladding material (lower refractive index, for example, 1.540) is applied to the polyimide film by a spin coating method for a predetermined thickness (10 microns), and then is applied in a nitrogen atmosphere. The lower clad is manufactured by applying a heat treatment of 80 degrees for 1 hour. Next, the core material (higher refractive index, For example, 1.5 4 5) is also manufactured by the spin coating method (thickness: 8 μm). Next, in order to remove the core material other than the waveguide, for example, a metal mask such as a Ti thin film that can be adhered by EB vapor deposition is manufactured by a normal photoresist process, and reactive ion etching of oxygen gas or the like is performed. Perform anisotropic etching. Used Ti mask is removed with buffered hydrofluoric acid, etc., and the upper clad material (low refractive index, side, for example, 1.540) is again produced by the spin coating method (film thickness 10 Micron). Here, the organic film according to the present invention needs to withstand all heat treatments in the process of manufacturing the organic optical waveguide. In other words, in the process of manufacturing an organic optical waveguide, after spin coating, for example, in the case of fluorinated polyimide, baking is performed at 380 ° C. However, the problem is that the organic film in the flat crucified portion melted unevenly. This is because if the substrate is bent in this manner, an optical waveguide parallel to the substrate cannot be manufactured. In the case of a polyimidide fluoride waveguide, the present invention can be carried out as long as the organic film material is a polyimide film which is one of heat-resistant polymer materials. Cannot be implemented.

I will elaborate a little more on this. The organic film bends like a candy in which it is unevenly melted, and the general rule is that the glass transition point is Tg or less. When the temperature is further increased to above Tg, the temperature reaches the thermal decomposition onset temperature Tf. Therefore, Tp is defined as the maximum heat treatment temperature during the baking process for organic materials.

Tg of film> Tp of organic waveguide

It is desirable that Rather than "desirable", the organic film used in the present invention is a minimum condition,

Tf> Tp

Must be satisfied.

Specific values of Tp, Tg, and Tf for organic materials tend to be one of the following two types.

A: Organic material with Tp, Tg, Tf force of about 100 degrees to about 200 degrees

B: T _P , Tg, Tf force Organic material with about 300 to 400 degrees

Group A includes, for example, polymethyl methacrylate, polycarbonate, Organic materials for optics such as styrene are included. In the case of polymethyl methacrylate, Tp is about 80 degrees, Tg is about 100 degrees, and Tf is about 150 degrees.

The group B includes, for example, heat-resistant polymer materials having an aromatic ring or a crosslinked structure, such as polyimide and polysiloxane. In the case of polyimide, Tp is about 350 degrees and Tg and Tf are both 400 degrees or more. (For the molecular structure, light absorption characteristics, and manufacturing process of polysiloxane, see Usui et al. Excellent low-loss Bolima single optical waveguide ", IEICE Technical Report, 0ME94-47 (1994-09)).

As the film made of the organic material used in the present invention, it is more preferable that the group B, that is, the Tg and Tf are higher. This is because if the material having the higher Tg and Tf is used in the group B, an optical waveguide made of the material of the group A, an optical waveguide made of the material of the group B, or a combination thereof is formed on the film. This is because an optical waveguide consisting of the above also satisfies the above desirable conditions.

However, the reason why the classification tendency of the group A and the group B is described here is shown only as an example so that the minimum condition and the desirable condition of the present invention can be easily understood. In other words, in the question of the organic optical waveguide manufacturing process, it is important to emphasize the selection of the film material and the optical waveguide material so that the organic film in the flattened portion does not bend like unevenly melted candy. It is.

Fig. 2 (c) shows a metal mask 50 such as Ti with a hole in the removed portion immediately above the V-groove 20 to remove the organic optical waveguide and the film made of organic material directly above the V-groove 20. FIG.

FIG. 2 (d) shows a process in which the organic optical waveguide immediately above the V-groove 20 and the film made of an organic material are removed by reactive ion etching using oxygen plasma, and the V-groove 20 appears. When a single-mode optical fiber 60 having an outer diameter of 125 μm is inserted into the V-groove 20 that appears, the height of the core of the optical fiber 60 from the substrate surface becomes the center of the organic optical waveguide 40. Height from the substrate surface. An optical element can be completed by fixing it with an adhesive.

In the single mode, in the optical coupling between the optical fiber and the optical waveguide, the coupling loss increases by more than 10 dB when the core center is shifted by about 5 microns. Ie multi-mode Single mode waveguides are more strict than the core center deviation. In the present invention, since the core centers can be aligned by the simple method as described above, the present invention is particularly effective for a single-mode optical waveguide.

As described above, according to the present invention, by providing a flattening method that is simpler than the conventional method, in which a film made of an organic substance is attached to a substrate having a fiber guide groove, light by passive alignment is provided. Facilitates fiber mounting.

In addition, each of the methods shown in FIG. 2 may use the following method.

FIG. 3 shows another method of attaching a film made of an organic material to a substrate. That is, the polyimide film 30 is temporarily attached to another substrate 7 (FIG. 3 (a)). Next, the above-mentioned separate substrate with a film is attached with the hollow film 30 facing the substrate 1 () (FIG. 3 (b)). At this time, the relationship between the adhesive force F7 of the polyimide film 30 to another substrate 7 and the adhesive force F10 to the substrate 10 is set so that F10> F7. Finally, using the difference in the adhesive strength of F10> F7, only the separate substrate 7 is peeled off (Fig. 3 (). With this method, the polyimide film 30 does not sag in the V-groove 20) There is an effect that it can be stuck flat.

Further, in order to create the difference in the adhesive force of F10> F7, adhesives having different adhesive forces may be used. However, even if the same adhesive is used, before the adhesive agent shown in FIG. By immersing the substrate with the film in an extremely permeable solvent such as hydrofluoric acid to weaken the adhesive strength with another substrate 7, it is possible to create an adhesive strength of F10> F7. In this case, since the same adhesive may be used, it is effective when there are few kinds of adhesives that can be used.

Also, when fabricating an organic optical waveguide, an electron beam or ultraviolet light is selectively irradiated to cause a chemical change only in some organic materials, and a refractive index distribution is created using the refractive index change accompanying the change. (Refer to Y. Tamada, et al., "Limbeddod Channel Folyi mide Waveguide Fabrication by Direct Electron Beam Writing Method", Journal of Lightwave Technology. , vol. 13, page l718, 1995) ₀ Further, the end face may be formed by dicing. FIG. 4 (a) shows a state in which an end face is formed by the dicing cut 71. FIG. In order to obtain the state of FIG. 4 (b), the organic optical waveguide 40 and the polyimide film 30 on the V-groove 20 are physically removed from the state of FIG. 4 (a) by tweezers or the like. I just need. The organic optical waveguide 40 and the polyimide film 30 on the V-groove 20 have a smaller bonding area with the substrate 10 because of the V-groove type. This is because the adhesive strength is relatively weak. This method is simpler than the end face formation by reactive etching. This is because, in any case, dicing is used to scribe a Si substrate of about 1 mm in the element fabrication process. That is, if the end face forming step and the element forming step are performed at the same time by dicing, one step can be omitted, and there is an effect that the process can be further simplified.

Regarding the end face formation by dicing, particularly in the case where a Si substrate is used for the substrate 10 and the V groove 20 is used as the optical fiber guide groove, where to dice in the K direction of the V groove 20 There are two ways: FIG. 5 (a) shows an external perspective view, and FIG. 5 (b) shows a cross-sectional view taken along line A-— '. As clearly shown in Fig. 5 (b), the V-grooves 20 are all composed of Si (1 1 1) planes. I have.

One position of the dicing cut 71 is just before the V-groove 20 (FIG. 6 (a)). In this case, even if the organic optical waveguide 40 and the polyimide film 30 on the V-groove 20 are peeled off and the optical fiber 60 is fixed, the V optical gap between the organic optical waveguide 40 and the optical fiber 60 remains. The distance increases by the slope of the (111) plane of the groove (Fig. 6 (b)). In this case, the distance is about 63 microns, which is the same as the V-groove depth. Then, there is a problem that the optical coupling loss increases here. Therefore, it is necessary to polish the optical fiber side obliquely to match the slope of the (111) plane of the V-groove, which is troublesome.

Another position of the dicing cut 71 is a position where dicing is performed on the slope of the V-groove (FIG. 7 (a)). In this case, the distance between the organic optical waveguide 40 and the optical fiber 60 can be reduced to zero if the thickness of the dicing blade is 63 μm or more above the slope. That is, the thickness of the dicing blade By simply considering the position of the dicing cut 71, the optical coupling loss can be minimized.

The present invention is effective for all passive devices that have been reported so far, such as optical power plugs and filters. This is because, in the case of the present invention, since the alignment with the fiber is completely passive, the passive element has no special meaning and the fiber can be mounted without any change. . The present invention has a dramatic effect as compared with the conventional active alignment method, especially when the number of input / output optical fibers is large. Figure 8 shows a 1: 4 force bra for reference. 1: From a two-stroke brush]: At the point of reaching 16, the variation of the output light depends only on the precision of the groove formation. Therefore, the deterioration of the element-characteristics does not occur because the number of input / output lines increases. . Regarding the time required for the alignment, the alignment with the fiber is completely passive, so it takes only a short time, and as a result, the dramatic increase in the number of input / output lines does not occur. As described above, the present invention is effective for passive elements, particularly for passive elements having a large number of input / output lines.

(Example 2)

The present invention is even more effective in active devices that utilize the energy from the electrodes to alter the physical properties of the waveguide. i In this example, 1 in Figure 9:

2 shows a heat effect type optical switch of FIG. In this element, an electrode 72 is provided on a waveguide, and a current flows through only one of the electrodes, so that a heater section 73 provided immediately above the waveguide heats only one of the electrodes. As a result, the refractive index of the organic optical waveguide on one side of the 1: 2 configuration decreases, and light propagates only to the unheated waveguide (for example, GF is a heat effect type optical switch). Lipscomb, et al., "Packaged thermo-optic polymer 1x2 switch", OFC'95 Technical Digest, WS10) ₀ In such an active element, the input and output fibers were temporarily fixed. In addition, the input and output fibers must be fine-tuned and fixed so that the optical output is maximized by moving the active part of the device. For this reason, it is necessary to control the fine adjustment in addition to the total number of input and output fibers as well as the number of patterns to determine the type of electric energy to be applied to the electrodes. Become difficult. In the present invention, since the alignment with the fiber is completely passive in this case, it is sufficient regardless of the number of electric energy patterns. That is, since the present invention can be carried out in the same manner as in the case of the passive element, the alignment of the fiber of the optical element utilizing the effect of the electric energy by the electrodes can be easily carried out, and is more effective than the passive element.

In the thermal effect type optical switch as described above, if the substrate is a Si substrate having excellent thermal conductivity and easy to mount the fiber, heat is not trapped, so that the switching beads are faster, which is more effective. is there.

In the heat effect type optical switch as described above, the electrode is usually provided at the bottom of the organic waveguide, but may be formed below the organic waveguide. This is because if there is a step on the top of the organic waveguide, unevenness in the film thickness and blurring of the focus when applying the photoresist will occur, and precise pattern accuracy cannot be obtained. For example, if the step is about 3 microns, a pattern width error of about 3 microns occurs above and below the step. However, by forming the electrodes below the organic waveguide, it is possible to prevent a step from occurring at the time of forming the electrode pattern, so that the error in the pattern width can be reduced to 0.5 μm or less, which is a normal value.

FIG. 10 is an explanatory diagram of a manufacturing method for forming an electrode below an organic waveguide. FIG. 10 (a) is a view in which after V grooves 20 are flattened with a polyimide film 30, an electrode material is deposited, and an electrode pattern is formed by ordinary photolithography. Since the thickness of the electrode material is as small as about 1 micron at most, the organic optical waveguide 40 can be manufactured without any problem (FIG. 10 (b)).

FIG. 10 (c) shows a metal mask made of a metal such as Ti with a hole in the removed part to remove the organic optical waveguide and the film made of an organic material directly above the V-groove 20 and near the electrode. FIG.

FIG. 0 (d) shows that the film made of the organic optical waveguide and the organic material immediately above the V-groove 20 and near the electrode is removed by reactive ion etching using oxygen plasma, and the V-groove 20 and the electrode 7 are removed. Step 2 appears. The electrode itself becomes a metal mask, and the film made of organic material immediately below the electrode remains. An electrode pad is formed, but the part without the electrode pattern is etched and the substrate surface appears.

Here, there is a force that the polyimide film 30 has between the heater unit 73 and the substrate 10, and it is important for the thermal effect type optical element that this is present. Because the thermal conductivity of Si is l ⁴ 8W / _m. K, quartz glass is 14 W / _m. K. Since these values are two digits and one digit, respectively, higher than those of organic materials, if there is no polyimide film 30, almost all the heat of the heater 73 will escape to the substrate 10 and the optical element Will not work. Therefore, the polyimide film 30 plays a role not only as a substrate having a flat iU but also as a heat insulator between the substrate 10 and the lower heater of the optical waveguide.

As described above, according to the present method, the problem of film thickness unevenness and defocusing at the time of photo resist coating can be solved without increasing the number of processes by merely changing the order of fabrication, and the precision of the electrode can be improved. There is an effect that bang accuracy can be obtained.

Further, a waveguide type semiconductor optical device as shown in FIG. 11 can be integrated by using the manufacturing method shown in FIG. That is, the waveguide type semiconductor optical device 76 can be passively mounted on the electrode pad 75 by reflow bonding. (As a conventional example of the passive mounting method of the semiconductor device, the direction parallel to the substrate is Hashiki et al., “Installation of LL by passive alignment on PLC platform, mounting of monitor and PD” "Institute of Electronics, Information and Communication Engineers, General Conference, 1996, C-206, Ito et al.," Passive line technology for optical devices ", Journal of Japan Institute of Circuit Packaging, vol. 10, No. 5 (1995), 302 302 See). For example, a transmission / reception optical circuit can be realized by using one of the optical elements 76 as a laser and the other as a photodetector. (For a conventional example of a transmission / reception optical circuit, see Yamada et al., “Filter reflection type using PLC platform.” WI) M Transmit / Receive Optical Circuit ", IEICE Institute of Electronics, Information and Communication Engineers, University of Tokyo ^^, SC-2-5). However, polyimide film 30 needs to be a heat-resistant polymer. By using this method, there is an effect that downsizing due to integration and simplification of alignment between optical elements can be achieved.

Further, by using the manufacturing method shown in FIG. 10, the material of the array type optical element as shown in FIG. 12 can be saved. FIG. 12 (a) shows a conventional method. semiconductor The element interval a of the optical element array 78 is designed to be the same as the interval b of the optical fiber array 61, and is usually at an interval of 25 microns. FIG. 12 (b) illustrates the present invention. 11 is different from FIG. 11 in that there is an organic optical waveguide array 41 having different waveguide intervals at the input / output ends, and an array-type semiconductor optical element 7 8 is provided on the side of the organic optical waveguide array 41 where the waveguide interval is smaller. There is a configuration. As a result, the element interval a of the semiconductor optical element array can be made smaller than the interval b of the optical fiber array 61, and material saving of the array type optical element can be achieved. For example, if a ': a == l: 2, twice as many semiconductor optical element arrays can be obtained from a wafer of the same size as before, and the alignment can be made passively, which is shorter than before. The effect is that the optical fiber can be mounted in a short time.

(Example 3)

The present embodiment proposes a device manufacturing method in which a film 31 made of an organic material to be attached for flattening a substrate is also used as a lower clad of an organic optical waveguide. FIG. 13 (a) shows a step of attaching to a substrate, and FIG. 13 (b) shows a step of manufacturing a waveguide. The subsequent device fabrication process is the same as in the first embodiment.

The organic film 31 to be adhered to the substrate 10 has a refractive index equal to or smaller than the cladding material of the organic optical waveguide provided thereon. In the case of the first embodiment, the material of the organic film 31 is a film-like fluorinated polyimide (refractive index: 1.540). One spin coating step can be reduced, and the organic optical waveguide 42 can be manufactured extremely easily.

Further, the proposal according to the present embodiment has an effect that a buffer layer having a thickness of about 20 μm, which is usually provided to reduce propagation loss, can be manufactured much more easily than in the past.

Normally, the maximum film thickness per one time in which the in-plane distribution is excellent by the spin coating method is about 10 micron. For this reason, in order to produce the above buffer layer of about 20 microns, it is necessary to apply two or three coats. However, as shown in the present embodiment, the film can be shared with the lower clad of the organic optical waveguide, for example, For example, if a 20 micron film is attached, the thickness of the film itself will increase due to the increase in thickness, and there will be the advantage that the grooves can be flattened without sagging, while there is the advantage that a thicker buffer layer can be easily obtained. .

(Example 4)

As described in the first, second, and third embodiments, the present invention has the effect of facilitating the mounting on the optical fiber as compared with the related art since the present invention has the optical fiber guide groove. . The present embodiment takes advantage of this effect to provide an unprecedented photon.

This is an example of collecting a plurality of optical elements according to the present invention into one package. Even if only a small-scale fogger can be simplified, the combination can be simplified, so that a large-scale power bra can be easily realized. The configuration may be as shown in FIG. Therefore, the present invention is particularly useful for a system that requires a large-scale optical power puller, because the scale of the optical component can be easily increased.

Further, in such a configuration, when connecting a large number of low-scale optical components, the optical fiber becomes complicated. Also in this case, as shown in FIG. 15, when the optical waveguide group 101 is provided and functions as an optical connector, it is possible to simplify the mounting complexity.

The optical switch described in the fourth embodiment can be easily used for the following system. For example, a protection switch or an optical cross-connect device.

The term "protection switch" is a general term for a function in which a transmission line is given redundancy in advance so that the transmission line can be operated without trouble by switching the switch in the event of a failure, thereby improving the reliability of the entire transmission line. In particular, low cost is desired for protection switches such as optical subscriber lines. In this regard, the use of the optical switch according to the present invention is effective in this respect.

A cross-connect device virtually divides the transmission bandwidth of an installed physical transmission path into several path capacities. The difficulty with this cross-connect device is that it must be dropped to a 150 Mbps signal, for example, because the switch is an electrical switch. Therefore, especially for switching the path of the transmission line of the Gbps class, a DEMUX device for reducing the signal speed to that extent and a MUX device for increasing the switched signal to the Gbps class become huge. Here, if the optical switch described in the fourth embodiment is used, switching can be performed at a signal speed of a pass class, and as a result, the DEMUX device and the MUX device are not required, and the overall size and size are reduced. Can be expected. This system is called an optical cross-connect system.

However, the key to the cost reduction is the cost of the optical switch. In this case, a 4-input 4-output optical switch or an 8-input 8-output optical switch is used. Conventional optical switches have problems with fiber mounting, as described above, and could not be realized at low cost. However, in the present invention, fiber mounting can be easily performed, so that it can be realized at low cost. Even if only a small-scale optical switch can be simplified, the combination can be simplified, so that a large-scale switch can be easily realized. The configuration may be as shown in FIG. 14 or FIG. Therefore, the present invention is particularly effective for other optical switch application systems, because it is easy to increase the scale of optical components and to easily mount active elements with fibers.

In all of the above embodiments, the description has been made using the optical fiber as the optical component. However, it is only necessary that the optical component has a function of transmitting and receiving light parallel to the substrate.

Similarly, as the substrate material, the Si-V groove was used, but a glass material, an organic material, or the like in which the similar groove was precisely processed may be used.

As described above, according to the present invention, there is an effect that mounting of an optical fiber by passive alignment can be extremely easily realized by a simple flattening method of attaching a film made of an organic material.

Industrial applicability

INDUSTRIAL APPLICABILITY According to the present invention, an optical fiber mounting by passive alignment can be realized very easily by a simple flattening method of attaching a film made of an organic material, and the industrial applicability is great.

Claims

The scope of the claims

1. A substrate having an optical component positioning recess on its surface;

Optical waveguide means made of an organic material having a light propagation direction parallel to the substrate surface on the substrate,

A method for manufacturing a waveguide-type optical element having a function of injecting or emitting light parallel to the substrate surface, and having an optical component fitted in the positioning recess, wherein the surface has an optical component positioning recess A method for producing a waveguide-type photoelement, comprising a step of attaching a film made of an organic material to a substrate.

2. The method for manufacturing a waveguide-type optical element according to claim 1, wherein the optical waveguide means made of an organic material is a single mode.

3. An organic material having a refractive index higher than that of the film is provided directly above the film made of the organic material, and the organic material having a refractive index higher than that of the film is a core of the optical waveguide. 3. The method for manufacturing a waveguide optical device according to claim 1 or 2.

4. The method of manufacturing a waveguide-type optical device according to claim 1, wherein the optical waveguide is a passive device having two or more input / output ends.

5. A waveguide-type light source for fT in which an electrode is provided above or below the optical waveguide, wherein light is controlled by applying electric energy from the electrode. The method for manufacturing a waveguide optical device according to any one of 1 to 4.

6. A waveguide-type optical device having a configuration in which electrodes are immersed in the upper or lower part of the optical waveguide, wherein the substrate is a Si substrate, and the electrodes generate heat. 6. The method for manufacturing a waveguide-type optical element according to claim 5, wherein light is controlled by utilizing the change in physical properties.

7. The waveguide-type optical element, wherein the film made of the organic material fiii is made of a heat-resistant polymer material, and the electrode provided near the entrance or exit end M of the optical waveguide; The electrode of the optical element is optically connected to the optical waveguide, and is electrically connected to the electrode. Device manufacturing method.

8. The optical waveguide has a structure in which both ends of the optical waveguide have different waveguide spacings, and the semiconductor light 8. The method for manufacturing a waveguide-type optical device according to claim 7, wherein the device has an array-type device structure.

9. A plurality of the waveguide-type optical elements manufactured by the manufacturing method according to any one of claims 1 to 8, wherein input / output ends of the optical elements are connected to each other by optical waveguide means, A waveguide-type photoelement, wherein all of them are in a single package.

10. An optical transmission line system using an optical switch produced by the manufacturing method according to claim 5 as a protection switch.

11. An optical cross-connect device using an optical switch produced by the manufacturing method according to claim 5.