TW201319650A - Method of fabrication for an asymmetric Bragg coupler-based polymeric filter with a single-grating waveguide - Google Patents

Abstract

The present invention discloses a Method of Fabrication for an asymmetric Bragg coupler-based polymeric filter with a single-grating waveguide. A negative photo-resist film is coated on a substrate and formed asymmetric negative waveguide pattern as a mold. This mold is subsequently used to produce a polydimethylsiloxane (PDMS) stamp with waveguide pattern. This PDMS stamp is then used to transfer the waveguide pattern onto UV polymeric cladding layer. The cladding layer is injected with waveguide cores and covered with upper cladding layer, finally the fabrication of asymmetric Bragg coupler-based polymeric filter is completed.

Description

Method for manufacturing asymmetric Bragg coupling polymer filter with single grating waveguide

The present invention relates to a method for fabricating an asymmetric Bragg coupling polymer filter having a single grating waveguide, and more particularly to a method for fabricating an asymmetric Bragg coupling polymer filter of a single grating waveguide.

It is well known that an optical add/drop multiplexer (OADM) enables a specific wavelength in an optical fiber communication to be elastically inserted or removed, which has become a wavelength division multiplexing (WDM) network technology. An indispensable component. Wavelength division multiplexed (WDM) access technology has proven to be a key technology for global dissemination of multimedia communications within fiber-optic networks to accommodate large amounts of bandwidth. In a wavelength division multiplexed (WDM) based network, it is necessary to use an optical plug multiplexer (OADM) to insert (increase) or capture (drop) a particular wavelength in a fiber optic communication system. These components allow for the extraction of wavelengths in the transmission loop and the addition of some wavelengths into the network (see Annex 4, Reference 8). A number of optical complement/light extraction architectures based on optical waveguides have been demonstrated. These include Mach-Zehnder interferometer (MZI) based on optical complement/light filter, grating-assisted isotropic coupler, asymmetric Bragg coupler (ABC) (Reference 8), and Bragg reflector gateway waveguide filter . Mach-Zehnder interferometers based on optical complement/light extraction filters produce good insertion loss and channel insulation, which can be built on both all-fiber and integrated optical platforms. However, they are extremely sensitive to the balance of the interferometer and the position of the two gratings when implemented. Therefore, some post-manufacture overall designs are often required. It is currently known that grating-assisted omnidirectional couplers composed of two dissimilar waveguides and a long period grating have been widely discussed for use as wavelength filters. It has the advantage of a long grating period (about several tens of centimeters), making it easy to manufacture using standard photolithography, and having low back reflection characteristics to avoid unwanted optical resonance. The main disadvantage of this device is that it requires a long interaction grating length (approximately several hundred grating periods) when it is operating in a small spectral bandwidth. Therefore, this device is not beneficial for the integration. The Bragg reflector gateway waveguide filter has good return loss and crosstalk characteristics, as well as inherent stability. However, because it requires non-interactive optical propagation, its use in integrated optical formats is limited. As for the optical filter based on the asymmetric Bragg coupler, because it operates in the opposite direction mode, it is sensitive to the grating position when obtaining the desired optical filter spectrum, so they have better stability. It is easier to reproduce mass production than the optical filter based on the Mach-Zehnder interferometer.

Since the polymer material provides an imaginable technical platform mode for manufacturing complex but flexible body devices, these materials are particularly suitable for the fabrication of wavelength division multiplexers on a planar substrate because of their low Cost benefits, easy to perform, and mechanical flexibility. Bragg gratings are fabricated on the polymer surface, which provide narrow bandwidth, low crosstalk, and flat-top passbands, and have become important components for different applications in optical communications and optical sensing. For example, Butler et al. used a polymer surface to release a Bragg grating on an integrated optical waveguide structure to fabricate a chemical sensor. Noh et al. demonstrated a cost-effective tunable wavelength laser based on a polymer waveguide Bragg reflector thermal/light coordination for use in WDM optical communications. The application of other tunable lasers and optical filters has also been demonstrated (Annex 4 Reference 21).

Previously, the inventors have demonstrated a process for rapidly forming sub-micron gratings on polymeric optical filters (e.g., Annex 4, Reference 11). It achieves high aspect ratios and vertical sidewalls, and achieves a grating that is consistent in UV polymer replication. The present inventors have recently developed and demonstrated a good process by rapidly producing a grating having a sub-micron range by using a generally economical soft printing technique, a micro-molding technique, and a holographic interferometric interference technique. An asymmetric Bragg coupling filter with a single grating waveguide.

SUMMARY OF THE INVENTION A primary object of the present invention is to provide a method for fabricating an asymmetric Bragg coupling filter having a single grating waveguide that is simple, fast, and capable of fabricating high aspect ratio gratings. The technical means for achieving the object is to coat the substrate with an ultraviolet polymer film and a negative photoresist film. A two-groove photoresist pattern is formed by exposure to a negative photoresist. The photoresist film and a trench are coated with a silicone film, and the positive photoresist is coated on the other trench. The photoresist is exposed to form a grating in the trench. Another silicone film is coated to peel the tantalum film from the photoresist mold. The silicone film is coated on the photoresist mold and filled with a groove, and another silicone film is coated on the photoresist mold and filled with another groove to form a silicone stamp. The two waveguides and the grating are transferred onto the ultraviolet-curable polymer film by a silicone stamp to form a coating layer. An ultraviolet curable polymer is injected into the two trenches of the cladding layer to form a waveguide core, respectively. The UV-curable polymer film is then placed on the coating to complete the manufacture of the filter.

one. Basic technical features of the present invention

As shown in FIGS. 1 to 4, a method for manufacturing an asymmetric Bragg coupling polymer filter having a single grating waveguide according to the present invention comprises the following steps:

(A) sequentially coating a UV-curable polymer film 11 and a negative photoresist film 12 on a glass substrate 10 (as shown in Figures 1 and 2 (a));

(B) irradiating the negative photoresist film 12 with ultraviolet light through a mask 13 (as shown in FIGS. 1 and 2(b)), and forming a first trench 14 and a width of different widths on the negative photoresist film 12. The second trench 15 is used as a photoresist mold 16 (as shown in FIG. 2(c));

(C) laminating a first silicone film 17 on one side of the photoresist mold 16 and filling the first trench 14 (as shown in FIGS. 1 and 2(d)) to bake and cure the first silicone film 17;

(D) depositing a specific amount of positive photoresist 18 on the other half of the photoresist die 16 and filling the second trench 15 (as shown in Figures 1 and 2(e));

(E) exposing the positive photoresist 18 by a full-image lithography interference technique to form a first grating pattern 19 in the second trench 15 (as shown in FIG. 1, FIG. 2(f) and FIG. 2(g));

(F) coating a second silicone film 20 on the photoresist mold 16, filling the second trench 15 and covering the first silicone film 17 (as shown in Figures 1 and 3(a)), The second silicone film 20 is baked and cured;

(G) the second silicone film 20 is peeled off from the photoresist mold 16, and the first silicone film 17 is peeled off from the photoresist mold 16 (as shown in Figs. 1, 3(b) and 3(c). );

(H) A third silicone film 21 is coated on one side of the photoresist mold 16 and filled with the second trench 15 (as shown in FIGS. 1 and 3(d)), and the third silicone film 21 is baked and cured. , the first grating pattern 19 is transferred to the third silicone film 21 to form a second grating pattern 22;

(I) a fourth silicone film 23 is coated on the photoresist mold 16, and fills the first trench 14 and covers the third silicone film 21 (as shown in Figures 1 and 3(e)). The four silicone film 23 is baked and cured;

(J) peeling the fourth silicone film 23 together with the third silicone film 21 from the photoresist mold 16 (as shown in FIGS. 1 and 3(f)), and forming a first silicone film 23 in combination with the third silicone film 21. a silicone stamp 24 (shown in FIG. 3(g)), the silicone stamp 24 has a first ridge 25 and a second rib 26 corresponding to the shapes of the first groove 14 and the second groove 15, The second ridge 26 has a second grating pattern 22;

(K) coating the silicone stamp 24 on the first ultraviolet-curable polymer film 27 (as shown in FIGS. 1 and 4(a)), using the first ridge 25 and the second ridge 26 to make the first ultraviolet A third trench 28 and a fourth trench 29 are formed on the photocurable polymer film 27, and the second grating pattern 22 on the silicone stamp 24 is transferred to the bottom of the fourth trench 29 to form a third grating pattern. 30;

(L) curing the first ultraviolet curable polymer film 27 by irradiating broadband ultraviolet light (as shown in Figures 1 and 4(b));

(M) removing the silicone stamp 24 from the first ultraviolet-curable polymer film 27 (as shown in FIGS. 1 and 4(c)), and using the cured first ultraviolet-curable polymer film 27 as a filter. a cladding layer 31 (shown in Figure 4 (d));

(N) a specific amount of the first ultraviolet curing polymer 32 is injected into the third trench 28 and the fourth trench 29 (as shown in Figures 1 and 4 (e)) to form the waveguide core 33 / 34;

(O) depositing a third ultraviolet-curable polymer film 35 on the cladding layer 31 (as shown in FIGS. 1 and 4(f)) to close the third trench 28 and the fourth trench 29;

(P) irradiating the third ultraviolet-curable polymer film 35 with ultraviolet light (as shown in FIGS. 1 and 4(g)) to cure the third ultraviolet-curable polymer film 35 to form an upper cover layer 36, and The upper cover layer 36 is crosslinked with the polymer of the cover layer 31 to complete the manufacture of the filter of the present invention.

two. Experimental example of the present invention 2.1 Production of the invention

Referring to Figures 2(a) to (g), Figures 3(a) to (g) and Figures 4(a) to (g), the asymmetric Bragg coupling polymer filter of the present invention has a single grating waveguide. In the manufacturing method, in the experimental example, a glass having a thickness of 700 μm was cut into a rectangle of 5 cm × 1 cm to serve as the substrate 10. After the substrate 10 is cleaned, the ultraviolet curable polymer film 11 (in the experimental example of the present invention, the polymer film is OG146 epoxy resin, which is produced by American company Epoxy Technology Inc.) is coated on the substrate 10 and reused. The UV-curable polymer film 11 was coated with a negative photoresist film 12 having a thickness of 6.0 μm by spin coating technique at a rotation speed of 1000 rpm for 17 seconds. The negative photoresist film 12 is irradiated with ultraviolet light for about 9 seconds via a mask 13 made of polyethylene terephthalate (PET) using a UV mask aligner. Then, a SU-8 negative photoresist developing device is used for 45 seconds to form a first trench 14 and a second trench 15 on the negative photoresist film 12 to form a photoresist pattern 16. The photoresist pattern 16 is then Used to produce a silicone stamp 24, which is then used to transfer the grating pattern to a UV curable polymer (the experimental example of the invention employs an Ormo-comp UV-catalyzed polymer manufactured by the German company micro resist technology GmbH, The solidification has a volume shrinkage of about 5-7% and a thermal stability temperature of 270 ° C). An image of a cross section of the end face of the photoresist 16 observed by an optical microscope (OM) is shown in Fig. 1 of the accompanying drawings.

In order to eliminate self-reflection from the input, the grating of the waveguide is fabricated on one of its waveguides (drop terminal). That is, a low-viscosity layer of the first silicone film 17 is coated on one side of the photoresist mold 16 and injected into the narrow first trench 14 by using a capillary effect and assembled at a resolution of 0.1 μm. The needle of the micropositioning platform is measured by a microscope (ZAK microscopes, Taiwan) with a long working distance, and the focal length of the objective lens is 13 mm. The first silicone film 17 is then baked at a temperature of 90 ° C for one hour to cure, and the cured first silicone film 17 serves to prevent the narrow first groove 14 from being formed with a grating.

Then, using a spin coating technique, a positive photoresist 18 (Ultra 123 manufactured by MicroChem Corp. of the present invention) is spread on the other half of the photoresist die 16 and fills the second trench 15. Using the full image lithography interference technique, the positive photoresist 18 is exposed by the two-beam interference pattern, and the first grating pattern 19 is formed in the second trench 15, and the first grating pattern 19 formed by the positive photoresist 18 is in Ultra 123. The setting is effected in the developing device. In order to facilitate the peeling of the first silicone thin film 17 as a protective layer, a second silicone film 20 is coated on the photoresist mold 16 and fills the second trench 15 and covers the first silicone film 17. The second silicone film 20 is baked at a temperature of 90 ° C for one hour to be cured, and then the second silicone film 20 is peeled off from the photoresist mold 16 , and the first silicone film 17 is peeled off from the photoresist mold 16 . Referring to Figure 2 of the accompanying drawings, the present invention observes a state in which the positive photoresist 18 is filled in the wider second trench 15 after spin coating by an optical microscope. In the above silicone, the present invention employs polydimethyl siloxane (PDMS).

The photoresist mold 16 is used as a master mold for transferring the pattern of the waveguide and the grating to a third silicone film 21. That is, a third silicone film 21 is coated on one side of the photoresist mold 16 by a capillary effect, and the second trench 15 having the first grating pattern 19 is filled, and the third silicone film 21 is 90. The temperature of °C is baked for one hour to cure, and the first grating pattern 19 is transferred to the third silicone film 21 to form a second grating pattern 22. A fourth silicone film 23 is coated on the photoresist mold 16, and the first trench 14 is filled and covered with the third silicone film 21, and the fourth silicone film 23 is baked at a temperature of 90 ° C for one hour. Cured. The fourth silicone film 23 is peeled off from the photoresist film 16 to form a silicone stamp 24, and the silicone stamp 24 has a shape corresponding to the first groove 14 and the second groove 15. A first rib 25 and a second rib 26 have a second grating pattern 22 on the second rib 26. As shown in Figure 1 of Annex II, the tantalum stamp 24 is an image observed by a scanning electron microscope (SEM), showing a complete grating of a waveguide of the silicone stamp 24, with a grating period of 500 nm and a depth of 400-450 nm. The two quantities were obtained by measurement using an atomic force microscope (AFM). In the above silicone, the present invention employs polydimethyl siloxane (PDMS).

Then, the silicone stamp 24 is applied to the first UV curable polymer film 27, and the first UV strip 14 and the second strip 26 are used to form a third trench on the first UV curable polymer film 27. 28 and a fourth groove 29, and the second grating pattern 22 on the second ridge 26 of the silicone stamp 24 is transferred to the bottom of the third groove. The first ultraviolet curable polymer film 27 is cured by irradiating broadband ultraviolet light. Wherein, in order to increase the adhesion between the first ultraviolet-curable polymer film 27 and the glass slide 37, a layer of adhesion promoter (prime 08) film 38 is laid on the Pyrex glass slide 37, and the thickness is 30 μm. The spacer is placed on the glass slide 37 between the silicone stamp 24 and the adhesion promoter film 38. The first ultraviolet light curing polymer (Ormo-comp) is implanted and then irradiated with ultraviolet light having a wide band and a wavelength of 300 to 400 nm. After the complete catalysis, the silicone stamp 24 can be easily peeled off from the first ultraviolet-curable polymer film 27. The silicone stamp 24 is removed from the first UV-curable polymer film 27, and the cured first UV-curable polymer film 27 is used as a cladding layer 31 of the asymmetric Bragg waveguide filter. As shown in Fig. 2 of Fig. 2, the image observed by SEM shows that the state of the waveguide and the grating reproduced on the first ultraviolet-curable polymer film 27 is good, and also conforms to the dimensional dimension on the photoresist 16. The depth and width dimensions of the cross section of the second trench 15 (with grating) and the first trench 14 (without grating) are 5 μm × 9.7 μm and 6 μm × 6.9 μm, respectively, and the interval between the two is 2.4 μm, and the coupling length is About 15mm, the total length is about 5cm. In the above ultraviolet curable polymer, the present invention uses an Ormo-comp ultraviolet curable polymer produced by a micro resist technology (GmbH) having a refractive index of 1.505 in a light beam having a wavelength of 1550 nm.

A specific amount of the second ultraviolet curable polymer 32 is injected into the third trench 28 and the fourth trench 29 to form the waveguide core 33/34, respectively. Since spin coating may result in a thick non-conductive layer emerging outside the core 33/34, such that some coupling loss occurs during fiber input to the filter, the present invention employs another method, namely, injecting the second ultraviolet light curable polymer 32. In the third trench 28 and the fourth trench 29 of the waveguide, the fusion splicing machine and the micro-positioning probe platform are used under the detection of long working distance optical microscopy. After the second ultraviolet curing polymer 32 is injected into the third trench 28 and the fourth trench 29, the silicone film 39 is coated on a glass carrier 40 and covered in the third trench 28 and the fourth trench. 29, and removing the excess second ultraviolet curing polymer 32 outside the third groove and the fourth groove 29 by pressing at an appropriate pressure. The second ultraviolet curable polymer 32 is irradiated with broadband ultraviolet light. The glass slide 40 is removed to peel the silicone film 39 from the cover layer 31. The above ultraviolet curing polymer, the invention adopts Ormo-core ultraviolet curing polymer produced by micro resist technology (GmbH), which has a refractive index of 1.539 in a light beam with a wavelength of 1550 nm, which is an inorganic and organic mixed polymerization. The thermal stability temperature is 270 ° C.

The upper cover layer 36 is used in order to avoid optical losses due to surface scattering or asymmetric waveguide structures that are completely devoid of the guiding mode. A spacer having a thickness of 30 μm was interposed between the cladding layer 31 and a glass slide 41. The third ultraviolet-curable polymer film 35 is injected into the space between the cladding layer 31 and the glass slide 41 to form the upper cover layer 36, and the third ultraviolet-curable polymer film 35 is placed on the cladding layer 31. Upper to close the third trench 28 and the fourth trench 29. The third ultraviolet-curable polymer film 35 is irradiated with ultraviolet light to form the upper cover layer 36, and the coating layer 31 and the polymer of the upper cover layer 36 are cross-linked, thereby completing the manufacture of the filter (as shown in FIG. 5). ). The filter sample was cut and the end face was polished to obtain the final asymmetric Bragg coupling filter having a length of 4 cm, a width of 1 cm, and a thickness of about 60 μm. Figure 1 of Figure 3 is a cross-sectional view of the output of two asymmetric waveguides. Obviously, there is no unguided layer on the periphery of the core. In the above ultraviolet curable polymer, the present invention uses an Ormo-comp ultraviolet curable polymer produced by a micro resist technology (GmbH) having a refractive index of 1.505 in a light beam having a wavelength of 1550 nm.

2.2 Simulation of the invention

The basic waveguide properties, including mode patterns and effective refractive index, were verified using a finite different time domain beam propagation method (FDTD-BPM). The transmission characteristics of this waveguide, including minimum transmission and band width, are calculated by coupled mode equations [eg Annex 4 Reference 8]. Since the depth of the grating waveguide is changed with the thickness of the positive photoresist (Ultra-123) filled in the waveguide trench, the depth variation affecting the transmission characteristics is also analyzed in the upper simulation work. To avoid co-evolving coupling for good conversational operation, we use a highly asymmetric waveguide as the coupler to have a composite mode that is sealed to each single waveguide. For ease of alignment, the cross-sectional dimension of the narrow waveguide is fixed at a width of 7 μm and a depth of 6 μm. The width of the wide waveguide is fixed at 10 μm and the depth is recorded as d . The interval between the two waveguides is denoted by s , and the ranges are 3-6 μm and 2-3 μm, respectively. Figures 6 and 7 show the basic mode of a single waveguide, and Figures 8 and 9 show the synthesis mode of an asymmetric Bragg coupler under conditions of d = 4.5 μm and s = 2 μm. In the first and second modes, the overall overlap of the single and composite modes is 91.28% and 91.04%, respectively. The overall overlap of the single and composite modes has a minimum because the depth of the engraved grating waveguide is reduced by 25% relative to the original depth, ie 6 μm (see Figures 10, 11, and 11). This result means that there is a maximum transmission loss because the bidirectional cross energy transmission occurs with a depth difference of 1/4 of the original depth between the two waveguides. However, as described above, the configuration configuration of the present invention has a high asymmetric property. The effective refractive indices of the individual waveguides shown in Figures 6, 7, 8, and 9 obtained by the simulation were 1.533054 and 1.532288.

As defined in reference 8, the coupling coefficient is κ ₂₁ , and the relevant reflection reflectivity and filtering bandwidth are calculated from the waveguide mode patterns. Because the complex coupling is weak, in the minimum transmission T _min may be about output port by T _min = 1- R _max calculated from, where R _max is the maximum capture reflective (drop reflectivity). As shown in Figs. 10, 11, and 12, it can be found that the coupling coefficient κ ₂₁ changes depending on the depth of the waveguide engraved with the grating, and the difference is shown in the figure. Here, the grating depth and period are assumed to be 400 nm and 500 nm, respectively. This result shows that there is a switching (trade-off) between ₂₁ asymmetric waveguide and the coupling coefficient κ. The output transmission spectrum of the coupler with the condition d = 4.5 μm, s = 2 μm and coupling length L = 15 mm is shown in Fig. 17.

2.3 Measurement of the invention

The near-field aspect of the optical waveguide is observed using the end-fire coupling technique. The measurement system is drawn as shown in Figure 13. The sample was fixed in a three-axis micro locator 50 (manufactured by Newport Inc., USA). Single mode fibers and microscope objectives are used for input optical coupling and output image magnification, and they are also mounted on a three-axis micro-positioner 50 to facilitate critical alignment. The self-emissive light source is amplified and emits a light beam having a wavelength ranging from 1530 to 1560 nm as a broadband light source (the present invention uses Stabilized Light Source, PTS-BBS, available from Newport Inc., USA). The beam is polarized in the TE direction using an in-line polarizer 51 (ILP-55-N, Advanced Fiber Resources, China) and polarized with a controller 52 (F-POL-PC, US company Newport Inc.) . Produced) Control wavelength operation of about 1550nm. The polarization state is checked using a near-infrared precision linear polarizer (this invention uses 20LP-NIR, manufactured by Newport Inc., USA). The output mode field of the waveguide is captured by an IR-CCD (Model 7290 Micro Observer from the American company Electrophysics Inc.) with image analysis software (LBA-710PC-D, V4.17, American company Spiricon Inc.). And shows the single mode feature of the waveguide. 14 and 15 show the field intensity distribution of the two-output waveguides of the two waveguides having a depth and width dimension of 4.5 μm × 10 μm and 6 μm × 7 μm, respectively, and an interval of s = 2 μm. The end of the narrow waveguide (without grating) of the ASE laser source with a power of 3 mW is used to avoid self-reflection, and the contour profile of the asymmetric mode is also observed.

In addition, insertion, cross-talk, and polarization dependent loss are all performed using an IR power meter (918D-Ir-OD3 & Model 1918-C, available from Newport Inc., USA). To measure. The use of broadband sources is to avoid the problem of optical interference. With TE polarized light, the insertion loss insertion loss was measured to be about 2.5 dB, and the conversation loss was about -12.8 dB. Polarization incidental loss (PDL) using the polarizatiln-scanning method [as in Annex IV Reference 22] shows that the PDL is about 0.15 dB.

The spectral characteristics of the self-reflecting asymmetric Bragg coupling filter were measured using a tunable laser system as shown in Figure 16 (Agilent 81640A, available from Agilent Inc., USA). The tunable laser 53 has a wavelength range of 1511-1562 nm and is controlled by a polarization controller 52. The output fiber of the tunable laser 53 is a polarization maintaining fiber in the form of Panda having a TE mode on a slow axis in the vertical direction. An aligned He-Ne laser source was used as the auxiliary source, combined with a broadband source using a 2 x 1 optical coupler. The optical filter 41 is attached to the micro locator 50, and the two single mode fibers are coupled as input and output beams, respectively, and are also mounted on the micro locator 50. The input beam is polarized in the TE direction as a mode field measurement system. The output fiber is coupled to the receiver end of the tunable laser 53 to characterize the operation of the filter.

A schematic diagram of the measurement system is shown in FIG. To avoid undesired reflections during optimal filter operation, the tunable laser is coupled to the narrow waveguide end of the filter 41 and coupled out by the other end of the same waveguide. As shown in Figure 17, the measurement results approximate theoretical expectations. At the Bragg wavelength, there is a single transmission drop of -9.2 dB. The measured Bragg wavelength is about 1532.8 nm, which is about 0.13 nm from the theoretical expectation (1532.67 nm). This 3 dB filter bandwidth is measured at approximately 0.125 nm with a difference of 0.025 nm from the simulation (theoretical bandwidth is approximately 0.1 nm). In addition, a 1531.6 nm edge was observed in the experimental data, which may result from Fabry-Perot etalon formed by the parallel plane of the fiber and the waveguide [see Reference 23]. We also measured the response of the filter's TM polarization, which showed an approximation and almost overlapped with the TE polarization spectrum, except for the -9.3 dB transmission drop. According to the numerical simulation, the central wavelength is expected to be 1532.62 nm, and its removal of TE transmission is only about 0.05 nm, reaching the resolution of the tunable laser system.

The above is only one of the possible embodiments of the present invention, and is not intended to limit the scope of the patents of the present invention, and the equivalent implementations of other changes according to the contents, features and spirits of the following claims are It should be included in the scope of the patent of the present invention. The invention is specifically defined in the structural features of the request item, is not found in the same kind of articles, and has practicality and progress, has met the requirements of the invention patent, and has filed an application according to law, and invites the bureau to approve the patent according to law to maintain the present invention. The legal rights of the applicant.

10. . . Substrate

11. . . Ultraviolet polymer film

12. . . Negative photoresist film

13. . . Mask

14. . . First groove

15. . . Second groove

16. . . Photoresist mode

17. . . First silicone film

18. . . Positive photoresist

19. . . First grating pattern

20. . . Second silicone film

twenty one. . . Third silicone film

twenty two. . . Second grating pattern

twenty three. . . Fourth silicone film

twenty four. . . Silicone stamp

25. . . First rib

26. . . Second rib

27. . . First ultraviolet curing polymer film

28. . . Third groove

29. . . Fourth groove

30. . . Third grating pattern

31. . . Coating

32. . . Second ultraviolet curing polymer

33/34. . . Waveguide core

35. . . Second ultraviolet curing polymer film

36. . . Upper cover

37. . . Glass slide

38. . . Adhesion promoter film

39. . . Silicone film

40. . . Glass slide

41. . . filter

50. . . Triaxial micro locator

51. . . Polarizer

52. . . Polarization controller

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a simplified schematic diagram of the process of the present invention.

Fig. 2 is a schematic view showing the specific flow of the preceding paragraph of the present invention.

Fig. 3 is a schematic view showing the specific flow of the middle section of the present invention.

Figure 4 is a schematic view showing the specific flow of the latter stage of the present invention.

Figure 5 is a schematic illustration of an asymmetric Bragg coupled polymer filter without an input waveguide grating of the present invention.

Figure 6 is a first synthetic mode diagram of the coupler structure of the present invention.

Fig. 7 is a second synthetic pattern diagram of the coupler structure of the present invention, having a cross-sectional dimension of 4.5 μm × 10 μm and 6 μm × 7 μm, and an interval s = 2 μm.

Figure 8 is a basic schematic view of a single waveguide of the present invention, having a width w = 10 μm and a depth d = 4.5 μm.

Figure 9 is a basic schematic view of a single waveguide of the present invention, having a width w = 7 μm and a depth d = 6 μm.

Fig. 10 is a schematic view showing a coupling coefficient of the present invention and a waveguide in which a grating is integrally overlapped with an individual pattern, with an interval of s = 3 μm, a width of a wide waveguide of 10 μm, and a width of a narrow waveguide of 7 μm.

Fig. 11 is a schematic view showing a coupling coefficient of the present invention and a waveguide in which a grating is integrally overlapped with an individual pattern, with an interval of s = 2.5 μm, a width of a wide waveguide of 10 μm, and a width of a narrow waveguide of 7 μm.

Fig. 12 is a schematic view showing a coupling coefficient of the present invention and a waveguide in which a grating is integrally overlapped with an individual pattern, with an interval of s = 2 μm, a wide waveguide width of 10 μm, and a narrow waveguide width of 7 μm.

Figure 13 is a schematic diagram of an experimental apparatus for measuring the field of the waveguide output mode of the present invention.

Figure 14 is a near field intensity profile of a wide waveguide with a grating of the present invention using an ASE laser having a power of 3 mW, illuminating a narrow waveguide.

Figure 15 is a near field intensity profile of a narrow waveguide with a grating of the present invention using an ASE laser having a power of 3 mW, illuminating a narrow waveguide.

Figure 16 is a schematic diagram of an experimental apparatus for transmission spectral measurement of the present invention.

Figure 17 is a transmission spectrum diagram of the asymmetric Bragg polymer waveguide filter of the present invention, the red line represents the experimental result, and the blue line represents the simulation result.

Attachment 1 is a photomicrograph of an asymmetric waveguide coupling pattern on a negative photoresist of the present invention. The cross-sectional dimensions of the two waveguide trenches are 6.8 μm×6 μm and 11.3 μm×6 μm, respectively, and the spacing between the two is 2.3 μm; 2 is an optical micrograph of the asymmetric waveguide coupler mold of the present invention, the positive light is resistively filled in the trench, and the cross-sectional dimensions of the two waveguide trenches are 6.8 μm×6 μm and 9.6 μm×5 μm, respectively, and the spacing between the two is 2.1. Mm.

Attachment 2: Figure 1 is a scanning electron microscope SEM observation of a silica gel with a grating angle of 30 degrees (grating period 500nm and depth of about 450nm); Figure 2 is a scanning electron microscope SEM observation groove showing a complete grating Patterns (sizes 6.8 μm x 6 μm and 9.6 μm x 5 μm, spacing about 2.4 μm, grating length 15 mm, and grating depth about 450 nm).

Annex 3: Figure 1 (a) is an optical micro-image of the output end of the filter wide waveguide (section size 5 μm × 9.6 μm); Figure 1 (b) is a filter narrow waveguide (section depth and width dimension) Optical lithography at the output of 6 μm × 6.8 μm); there is no unguided layer outside the waveguide core.

Annex 4: References.

Claims (10)

A method for fabricating an asymmetric Bragg coupling polymer filter having a single grating waveguide, comprising the steps of: (A) coating a substrate with a negative photoresist film; (B) passing the negative light through a mask The resistive film is irradiated with ultraviolet light, and a first trench and a second trench of different widths are formed on the negative photoresist film to form a photoresist film; (C) a half of the photoresist die is overlaid a first adhesive film is filled and the first silicone film is baked and cured; (D) a specific amount of positive photoresist is deposited on the other half of the photoresist mold and fills the second trench (E) exposing the positive photoresist with a full-image lithography interference technique to form a first grating pattern in the second trench; (F) coating a second silicone film on the photoresist pattern, and Filling the second trench and covering the first silicone film to bake and cure the second silicone film; (G) peeling the second silicone film from the photoresist film, and attaching the first silicone The film is peeled off from the photoresist mold; (H) a third silicone film is coated on one side of the photoresist mold, and fills the second trench, The third silicone film is baked and cured; (I) a fourth silicone film is coated on the photoresist mold, and the first trench is filled and covered with the third silicone film, and the fourth silicone film is baked. Curing; (J) peeling the fourth silicone film together with the third silicone film from the photoresist pattern, transferring the first grating pattern to the third silicone film to form a second grating pattern, and The fourth silicone film is combined with the third silicone film to form a silicone stamp having a first protrusion and a second protrusion corresponding to the shape of the first groove and the second groove. The second rib has the second grating pattern; (K) the squeegee stamp is coated on the first ultraviolet curable polymer film, and the first ridge and the second rib are used to make the first urethane Forming a third trench and a fourth trench on the photocurable polymer film, and transferring the second grating pattern on the silicone stamp to the bottom of the fourth trench to form a third grating pattern; Applying the first ultraviolet-curable polymer film to a broadband ultraviolet light to cure; (M) The glue stamp is removed from the first UV curable polymer film, and the cured first UV curable polymer film is used as a coating layer of the filter; (N) a specific amount of the second UV is The photocurable polymer is injected into the third trench and the fourth trench, and is irradiated with ultraviolet light to form a waveguide core respectively; (O) a third ultraviolet curable polymer film is deposited on the cladding layer to Blocking the third trench and the fourth trench; and (P) irradiating the third ultraviolet light curable polymer film with ultraviolet light to cure the third ultraviolet light curable polymer film to form an upper cover layer and The upper cover layer is crosslinked with the cover layer to complete the manufacture of the filter. The method for manufacturing an asymmetric Bragg coupling polymer filter having a single grating waveguide according to claim 1, wherein in step (A), a fourth ultraviolet light curing polymer film is coated on the substrate, and then The negative photoresist film is applied. The method for manufacturing an asymmetric Bragg coupling polymer filter having a single grating waveguide according to claim 1, wherein the fourth ultraviolet curable polymer film in the step (A) is an OG 146 epoxy resin. The method for manufacturing an asymmetric Bragg coupling polymer filter having a single grating waveguide according to claim 1, wherein the negative photoresist in step (A) is spin-coated at 6.0 rpm for 17 seconds. thickness. The method for manufacturing an asymmetric Bragg coupling polymer filter having a single grating waveguide according to claim 1, wherein the baking temperatures and times in steps (C), (F), (H) and (I) are respectively 90 ° C and 1 hour. The method for fabricating an asymmetric Bragg coupling polymer filter having a single grating waveguide according to claim 1, wherein the grating period and depth are 500 nm and 400-450 nm, respectively. The method for manufacturing an asymmetric Bragg coupling polymer filter having a single grating waveguide according to claim 1, wherein the refractive index of the ultraviolet curing polymer is 1.505 in a light source having a wavelength of 1550 nm, the second ultraviolet light The refractive index of the cured polymer was 1.539 in a light source having a wavelength of 1550 nm. A method of manufacturing an asymmetric Bragg coupling polymer filter having a single grating waveguide according to claim 1, wherein the ultraviolet light of the step (M) has a wavelength in the range of 300 to 400 nm. The method for manufacturing an asymmetric Bragg coupling polymer filter having a single grating waveguide according to claim 1, wherein the first trench and the second trench have a cross-sectional depth and width dimension of 5 μm×9.7 μm, respectively. And 6 μm × 6.9 μm, and the interval between the two is 2.4 μm, the coupling length is about 15 mm, and the total length is about 5 cm. The method for manufacturing an asymmetric Bragg coupling polymer filter having a single grating waveguide according to claim 1, wherein after the second ultraviolet light curing polymer is injected into the third trench and the fourth trench, a silicone film is coated on a glass slide and is coated on the third groove and the fourth groove, and is pressed by a suitable pressure to remove the third groove and the fourth groove The second ultraviolet light curing polymer, and after the second ultraviolet light curing polymer is irradiated with ultraviolet light, the glass slide is removed, and the silicone film is peeled off from the coating layer.