A silicon dioxide / polymer embedded waveguide based E 10 / E 01 Mode rotator and method for making the same

Abstract

An E / E mode rotator based on a silica / polymer embedded waveguide and a preparation method thereof belong to the technical field of photon integrated chip preparation. The E / E mode rotator of the present invention is composed of an Si substrate, an SiO2 lower cladding layer, a polymer core layer, and a polymer upper cladding layer from bottom to top. The polymer core layer is an embedded straight waveguide structure embedded in the SiO2 lower cladding layer, and the lower surface of the polymer core layer has a through square groove along the light transmission direction. In the present invention, a groove is prepared in the silica layer by two ICP etching processes, and then the silica groove is filled with a polymer. The side wall of the obtained polymer core layer is steep, which can reduce the device loss and improve the device performance. The device of the present invention has the advantages of compact structure, low loss, simple and mature preparation process, and low cost. It plays roles such as device connection and mode conversion in the optical network and has broad application prospects. 10 / E 01 The E / E mode rotator of the present invention is composed of an Si substrate, an SiO2 lower cladding layer, a polymer core layer, and a polymer upper cladding layer from bottom to top. The polymer core layer is an embedded straight waveguide structure embedded in the SiO2 lower cladding layer, and the lower surface of the polymer core layer has a through square groove along the light transmission direction. 10 / E 01 In the present invention, a groove is prepared in the silica layer by two ICP etching processes, and then the silica groove is filled with a polymer. The side wall of the obtained polymer core layer is steep, which can reduce the device loss and improve the device performance. The device of the present invention has the advantages of compact structure, low loss, simple and mature preparation process, and low cost. It plays roles such as device connection and mode conversion in the optical network and has broad application prospects.

Description

Technical Field

[0001] The present invention belongs to the technical field of photon integrated chip preparation, and specifically relates to an E-type integrated chip based on silicon dioxide / polymer embedded waveguide. 10 / E 01 Mode rotator and method for making the same. Background Art

[0002] Mode Division Multiplexing (MDM) technology refers to a technology that transmits multiple modes of light in the same waveguide to increase the capacity of optical communications. Mode multiplexers (demultiplexers) based on independent optical components, optical fibers and planar lightwave circuits (PLC) have been proposed. Among them, the mode multiplexer (demultiplexer) based on PLC has the unique advantages of low loss, small wavelength dependence, compact structure and high-volume production due to the use of mature semiconductor manufacturing technologies such as photolithography and ion etching. More importantly, polymer material PLC technology can integrate thermo-optical and electro-optical effects into the same device, easily realizing switchable or adjustable functions.

[0003] In order to increase the number of mode multiplexing on the PLC, it is necessary to activate E 10 and E 01 However, due to the limitation of waveguide mode symmetry, it is difficult to realize E 01 and E 10 (De)multiplexing of patterns is difficult to achieve. Summary of the invention

[0004] In order to solve the problems existing in the prior art, realize the first-order TE mode multiplexing, and improve the integration of photonic integrated chips, the present invention proposes an E-type photonic integrated chip based on silica / polymer embedded waveguide. 10 / E 01 Mode Rotator (ModeRotator) and preparation method thereof.

[0005] The E of the present invention 10 / E 01The mode rotator is composed of a Si substrate (1), a SiO2 lower cladding (2), a polymer core layer (3) and a polymer upper cladding (7) from bottom to top. The polymer core layer (3) is an embedded straight waveguide structure embedded in the SiO2 lower cladding (2). The upper surface of the polymer core layer (3) and the upper surface of the SiO2 lower cladding (2) are located in the same plane. The lower surface of the polymer core layer (3) has a through square groove along the transmission direction of light. The polymer upper cladding (7) is located above the polymer core layer (3) and the SiO2 lower cladding (2). The height and width of the polymer core layer (3) are 6μm×6μm, the width w of the square groove is 0.5-1μm, the height d is 0.5-1μm, the distance s between the square groove and the edge of the polymer core layer (3) is 1-1.5μm, and the length of the square groove is the same as the length of the polymer core layer (3), which is Lμm.

[0006] like Figure 3 As shown, Figure 3 (a) Corresponding to E 10 model, Figure 3 (b) Corresponding to E 01 mode, when there is no square groove on the lower surface of the polymer core layer (3), the input light will propagate in the embedded waveguide, and the light spot morphology will not change. 10 (E 01 ) mode light, the output end of the polymer core layer (3) is still E 10 (E 01 ) mode light. When the lower surface of the polymer core layer (3) is provided with a square groove, the waveguide structure is asymmetric, so the optical axis rotates when the light propagates in the waveguide. The parameters of the square groove are different, and the rotation angle of the optical axis is also different. By properly designing the parameters of the square groove, two orthogonal first-order TE mode lights whose optical axes rotate about 45° relative to the x-axis and the y-axis propagate in the square groove waveguide, and finally form a light field at the output end. Figure 3 (c) and Figure 3 (d) are the two orthogonal first-order TE mode lights mentioned above. When the light propagating in the waveguide satisfies Figure 3 (c) and Figure 3 (d), if the input light spot morphology at the starting end of the polymer core layer (3) is as follows Figure 3 (a) E 10 The mode light will output a light spot shape at the end of the polymer core layer (3) as shown in Figure 3 (b) E 01 mode light; on the contrary, the input light spot morphology at the starting end of the polymer core layer (3) is as follows Figure 3 (b) E 01 The mode light will output a light spot shape at the end of the polymer core layer (3) as shown in Figure 3 (a) E 10 Mode light.

[0007] When E is input into the waveguide core (3) 10 (E 01 ), the orthogonal first-order TE mode light with two optical axes rotated about 45° relative to the x-axis and y-axis is excited and propagated simultaneously in the square groove waveguide with different propagation constants β1 and β2. The propagation constant is calculated as shown in formula (1), where n eff is the effective refractive index of the mode, λ is the wavelength of the incident light, and the length L of the square groove waveguide is set to be the half-beat length, as shown in formula (2). The rotation of the optical axis causes the rotation of the spot shape. Input E 10 (E 01 ) mode light, the light spot rotates in the mode rotator, and finally obtains E at the output end after passing through a length L 01 (E 10 ) mode light.

[0008]

[0009]

[0010] The polymer core layer material may be an EPO core layer, SU-8 2005, SU-8 2002, a ZPU core layer, etc. In the present invention, SU-8 2002 is used as the polymer core layer material.

[0011] In order to confine light in the polymer core layer, the refractive index of the polymer upper cladding material needs to be smaller than the refractive index of the polymer core layer material. The polymer upper cladding material can be EPO cladding, PMMA, PDMS, ZPU cladding, etc. In the present invention, PMMA is used as the polymer upper cladding material.

[0012] The present invention discloses an E-type based on silica / polymer embedded waveguide 10 / E 01 The preparation method of the mode rotator comprises the following steps:

[0013] 1) growing a dense silicon dioxide lower cladding layer (21) with a thickness of 12 to 18 μm on a silicon substrate (1);

[0014] 2) evaporating a metal aluminum layer (51) on the silicon dioxide lower cladding layer (21);

[0015] 3) Spin-coating a layer of photoresist on the metal aluminum layer (51), and transferring the pattern on the mask plate with the same square groove structure and size as the polymer core layer (3) to be prepared to the metal aluminum layer (51) through ultraviolet exposure and development, to form an aluminum mask (52);

[0016] 4) etching the silicon dioxide lower cladding layer (21) by an ICP etching method using an aluminum mask (52) to obtain a silicon dioxide lower cladding layer (22) with a protrusion, wherein the structure and size of the protrusion are the same as the structure and size of the square groove to be prepared, and then removing the aluminum mask (52);

[0017] 5) Spin-coating a photoresist mask layer material on the silicon dioxide lower cladding layer (22) with the protrusions, and naturally cooling and curing after pre-baking to form a flat photoresist mask layer (61);

[0018] 6) by ultraviolet lithography, development, and post-baking, the pattern on the mask plate having the same structure as (the photoresist layer is a positive photoresist) or complementary structure (the photoresist layer is a negative photoresist) of the polymer core layer (3) to be prepared is transferred to the photoresist mask layer (61), thereby forming a photoresist mask (62) having a complementary structure to the polymer core layer (3);

[0019] 7) etching the protruding silicon dioxide lower cladding layer (22) not protected by the photoresist mask (62) again by an ICP etching method to form a silicon dioxide lower cladding layer (2) with a groove structure, wherein the groove structure has the same structure and size as the polymer core layer (3) to be prepared, and then removing the photoresist mask (62);

[0020] 8) Spin coating a polymer core layer material on the silicon dioxide lower cladding layer (2) with the groove structure, and naturally cool and solidify after pre-baking. The polymer core layer material fills the groove structure formed in step 7), and also forms a 0-5 μm polymer flat layer (4) on the upper surface of the silicon dioxide lower cladding layer (21) and the groove structure;

[0021] 9) etching away the polymer flat layer (4) by an ICP etching method to obtain a polymer core layer (3) in the silicon dioxide lower cladding layer (2), wherein the upper surface of the polymer core layer (3) and the upper surface of the SiO2 lower cladding layer (2) are located in the same plane;

[0022] 10) Spin-coating a polymer upper cladding layer (7) on the upper surface of the polymer core layer (3) and the silicon dioxide lower cladding layer (2) after etching away the polymer flat plate layer (4), heating and curing, and then cooling naturally to prepare the E based on silicon dioxide / polymer embedded waveguide of the present invention. 10 / E 01 Mode Rotator.

[0023] Compared with the prior art, the invention is innovative in that:

[0024] 1. The waveguide is a silicon dioxide / polymer embedded waveguide. First, a groove is prepared in the silicon dioxide layer by two ICP etchings, and then the silicon dioxide groove is filled with polymer. The side wall of the obtained polymer core layer is steep, which can reduce device loss and improve device performance;

[0025] 2. The waveguide is a silica / polymer embedded waveguide with a polymer material as the waveguide core layer. The refractive index of the upper cladding and core layer of different polymers is greater than 1.55, and the refractive index of the lower cladding silica is 1.445. The refractive index difference is greater than 2%. The large refractive index difference between the core layer and the lower cladding can achieve a more compact end face size, which is conducive to the preparation of large-scale optical waveguide integrated circuits;

[0026] 3. The function of mode rotation is realized by using grooves, and no external electrodes are required for modulation. The device preparation process is mature and the structure is simple;

[0027] 4. The designed first-order mode rotator can be connected with other devices embedded in the waveguide structure to achieve multi-mode multiplexing and increase the integration of the device.

[0028] In summary, the first-order mode rotation device based on the silica / polymer embedded waveguide platform proposed in the present invention has the advantages of compact structure, low loss, simple and mature preparation process, low cost, etc. It plays the role of device connection and mode conversion in optical networks and has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0030] Figure 1 : A cross-sectional schematic diagram of the mode rotator of the present invention;

[0031] Figure 2 (a): Schematic diagram of the three-dimensional structure of the mode rotator of the present invention; Figure 2 (b): Schematic diagram of the size parameters of the polymer core layer (3) of the mode rotator of the present invention;

[0032] Figure 3 (a): The mode rotator E of the present invention 10 Input / output light field diagram of the mode; Figure 3 (b): The mode rotator E of the present invention 01 Input / output light field diagram of the mode; Figure 3 (c) Figure 3 (d): Light field diagram of two orthogonal first-order TE modes excited by the input light;

[0033] Figure 4 : The simulated light field transmission diagram of the mode rotator of the present invention at a wavelength of 1550nm; Figure 4 (a): Input E 10 Light field transmission diagram of mode light; Figure 4 (b) Input E 01 Light field transmission diagram of mode light;

[0034] Figure 5 : Wavelength scanning transmission spectrum of the mode rotator of the present invention;

[0035] Figure 6 : Flow chart of the preparation process of the embedded waveguide mode rotator described in the present invention.

[0036] Figure 7 (a) : Process tolerance diagram of the groove depth of the mode rotator of the present invention; Figure 7 (b): Process tolerance diagram of the groove width of the mode rotator described in the present invention. DETAILED DESCRIPTION

[0037] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] Embodiment 1:

[0039] As attached Figure 1 As shown, it is a schematic cross-sectional view of a mode rotator based on an embedded waveguide, which, from bottom to top, consists of a Si substrate (1), a SiO2 lower cladding (2), a polymer core layer (3), and a polymer upper cladding (7). The SiO2 lower cladding (2) is grown by thermal oxidation or by PECVD (Plasma Enhanced Chemical Vapor Deposition) deposition. In this embodiment, thermal oxidation is used for growth, and the height is 15 μm and the refractive index is 1.4456. The polymer core layer (3) can be made of a polymer material with a negative thermo-optic coefficient. In this embodiment, SU-8 2002 material is used as the polymer core layer (3) material, and the refractive index is 1.5802. In order to excite the first-order mode light and reduce the process difficulty, the height a of the polymer core layer (3) is 6 μm and the width is 6 μm. The refractive index of the polymer upper cladding layer (7) is less than that of the polymer core layer (3). In this embodiment, polymethyl methacrylate (PMMA)-C10 photoresist is used as the material of the polymer upper cladding layer (7), with a refractive index of 1.47606 and a height of 4 μm.

[0040] As attached Figure 2The figure shows a schematic diagram of the three-dimensional structure of the mode rotator. The distance between the groove of the mode rotator and the edge of the waveguide is s, the width of the groove is w, and the height of the groove is d. In order to reduce the insertion loss between the input waveguide without a square groove and the rotation waveguide with a square groove, the size of the groove should be minimized. Finally, the groove size is determined to be 0.8μm in width w, 0.6μm in height d, and 1μm in distance s from the edge. Due to the introduction of the square groove, the waveguide has asymmetry, so the optical axis will rotate when the light propagates in the waveguide. Under this square groove parameter, two orthogonal first-order TE mode lights with the optical axis rotated by about 45° relative to the x-axis and y-axis propagate in the square groove waveguide, eventually forming a light field at the output end. Figure 3 (c) and Figure 3 (d) are the two orthogonal first-order TE mode lights mentioned above. When the light propagating in the waveguide satisfies Figure 3 (c) and Figure 3 (d), if the input light spot morphology at the starting end of the polymer core layer (3) is as follows Figure 3 (a) E 10 The mode light will output a light spot shape at the end of the polymer core layer (3) as shown in Figure 3 (b) E 01 mode light; on the contrary, the input light spot morphology at the starting end of the polymer core layer (3) is as follows Figure 3 (b) E 01 The mode light will output a light spot shape at the end of the polymer core layer (3) as shown in Figure 3 (a) E 10 Mode light. Two orthogonal first-order TE modes are excited and propagated simultaneously in the square groove waveguide with different propagation constants β1 and β2. The length of the mode rotator is set to half the beat length. According to formula (2), the length L is calculated to be 977 μm. The input E 10 (E 01 ) The mode light rotates through the optical axis, causing the light spot shape to rotate, and finally obtains E at the output end after passing through the length L. 01 (E 10 ) mode light.

[0041] Attached Figure 4 In the attached Figure 2 The spectrum of the first-order mode rotator working at a wavelength of 1550nm is shown in Figure (a). When the input E 10 After the mode light, E 10 The mode light gradually weakens and finally changes to E 01 Mode light; As shown in Figure (b), when the input E 01 After the mode light, E 01 The mode light gradually weakens and finally changes to E 10Mode light. In the figure, X and Z represent the width and length of the device, and the curve represents the value of the light intensity in the power monitor under different monitor paths. It can be seen from the figure that E 10 (E 01 )The final conversion degree of mode light is 99.275%.

[0042] Attached Figure 5 The figure is the wavelength dependence of the conversion efficiency of the designed first-order mode rotator at a wavelength of 1530nm~1565nm. It can be seen from the figure that the mode converter can function within the C-band broadband range and the conversion efficiency is greater than 98.5%.

[0043] As attached Figure 6 As shown in FIG. 1 , the process flow chart for preparing the waveguide intersection device embedded in the waveguide platform of the present invention comprises the following steps:

[0044] 1) growing a dense 15 μm thick silicon dioxide lower cladding layer (21) on a silicon wafer substrate (1) by thermal oxidation;

[0045] 2) using an aluminum evaporator to evaporate a 500 nm thick aluminum film (51) on the silicon dioxide lower cladding layer (21);

[0046] 3) Spin BP-212 diazonaphthoquinone type UV positive photoresist on the surface of aluminum (51) using a vacuum coating machine, control the speed to 2500 rpm, spin coating time 20s, heat at 87°C for 20 minutes and cure naturally. Photolithography for 3s under a 365nm UV photolithography machine, the light power is 23mW / cm 2 The structure and shape of the mask plate I used are the same as the size of the square groove, so that the pattern on the mask plate with the same structure and size as the square groove of the polymer core layer (3) to be prepared is transferred to the aluminum film to form an aluminum mask (52), which plays a role in protecting the aluminum mask. It is post-baked at 92°C for 20 minutes and naturally cooled to solidify, and then developed in 0.5% NaOH to remove excess aluminum film, and finally photolithography for 10 seconds to remove all BP-212 photoresist;

[0047] 4) etching the silicon dioxide lower cladding layer (21) using an aluminum mask (52) by an ICP etching method, wherein the gas introduced by the ICP is a C4F8 / SF8 mixed gas, and then removing the excess aluminum mask (52) using 0.5% concentration of NaOH, thereby obtaining a silicon dioxide lower cladding layer (22) with a protrusion of 0.6 μm in height on the silicon dioxide lower cladding layer (21);

[0048] 5) Spin coating the device in step 4) with SU-8 2005 photoresist from Micro Chem Co., Ltd., pre-baking at 60° C. for 10 minutes, 90° C. for 20 minutes and curing by natural cooling, and forming a 6 μm thick SU-8 photoresist mask layer (61) by controlling the rotation speed to 1000 rpm and the spin coating time to 20 seconds;

[0049] 6) Place the device in step 5) under a 365nm UV lithography machine with an optical power of 23mW / cm 2 , the structure and shape of the mask II used are the same as the structure and shape of the silicon dioxide groove to be prepared, the exposure time is 7s, and then it is post-baked at 65°C for 10 minutes and 95°C for 20 minutes, cooled to room temperature, developed in PGMEA (Propyleneglygol-monomethylether-acetate) developer, and then rinsed in isopropanol to remove the residual glue, and the reaction solution is washed with deionized water; then hardened at 120°C for 30 minutes to form a photoresist mask (62) complementary to the structure of the polymer core layer (3);

[0050] 7) Using the ICP etching method, using the same gas composition as in step 4), a groove structure with a height of 6 μm and a height of 0.6 μm is etched on the silicon dioxide lower cladding layer (22) with the protrusion, and a protrusion of 0.6 μm is formed in the groove, and then the photoresist mask (62) is removed.

[0051] 8) Using a vacuum coating machine, SU-82005 photoresist from Micro Chem is spin-coated on the surface of the lower silica cladding layer (2). The pre-baking process first needs to be carried out at 60° C. for 10 minutes, 90° C. for 20 minutes, and then naturally cooled and cured. The silicon dioxide grooves are filled by controlling the rotation speed to 3000 rpm and the spin coating time to 20 seconds. Since SU-8 is self-leveling, a 2 μm thick and smooth SU-8 flat plate layer (4) is formed on the upper surface of the lower silica cladding layer (21) and the groove structure.

[0052] 9) removing the 2 μm thick SU-8 flat layer (4) formed after filling by ICP etching method using the same gas composition as in step 4), thereby obtaining a polymer core layer (3), the upper surface of which is located in the same plane as the upper surface of the silicon dioxide lower cladding layer (2);

[0053] 10) Spin-coating polymethyl methacrylate (PMMA)-C10 photoresist on the upper surface of the polymer SU-8 core waveguide (3) and the silicon dioxide lower cladding (2) at a spin-coating speed of 3000 rpm, and then placing in an oven and heating at 120° C. for 2 hours to obtain a 4 μm thick polymer upper cladding (7), thereby obtaining the embedded waveguide first-order mode rotation device of the present invention.

[0054] In the actual process preparation, UV lithography and wet etching can easily widen the mask width, affecting the width of the device after dry etching. In the ICP etching process, a load effect will occur, that is, the local etching gas consumption is greater than the supply, causing the etching rate to decrease or the etching to be uneven, and the load effect cannot be completely eliminated, which will also cause the etching width to change. Due to the nonlinear change in the etching rate, the etching height cannot be accurately guaranteed. Therefore, the size of the groove part of the device will deviate from the design value after wet etching and dry etching. As shown in the attached figure Figure 7 As shown, the conversion efficiency of the mode rotator changes with the groove height d and the groove width w. When the groove height d changes within the range of the set value plus or minus 0.03μm, the conversion efficiency is greater than 97%, and when the groove width w changes within the range of the set value plus or minus 0.03μm, the conversion efficiency is greater than 98.6%. Therefore, when the device is actually prepared, the possible process error has little effect on the device conversion efficiency, and the device conversion efficiency is always maintained above 97%.

Claims

1. An E-based Silica / Polymer Embedded Waveguide 10 / E 01 A mode rotator, characterized in that: From bottom to top, it is composed of a Si substrate (1), a SiO2 lower cladding (2), a polymer core layer (3) and a polymer upper cladding (7). The polymer core layer (3) is an embedded straight waveguide structure embedded in the SiO2 lower cladding (2). The upper surface of the polymer core layer (3) and the upper surface of the SiO2 lower cladding (2) are located in the same plane. The lower surface of the polymer core layer (3) has a through square groove along the transmission direction of light. The polymer upper cladding (7) is located above the polymer core layer (3) and the SiO2 lower cladding (2). The height and width of the polymer core layer (3) are 6 μm×6 μm, the width w of the square groove is 0.5 to 1 μm, the height d is 0.5 to 1 μm, the distance s between the square groove and the edge of the polymer core layer (3) is 1 to 1.5 μm, and the length of the square groove is the same as the length L of the polymer core layer (3), which is half a beat length.

2. A silicon dioxide / polymer embedded waveguide based E according to claim 1 10 / E 01 A mode rotator, characterized in that: The polymer core layer material is EPO core layer, SU-8 2005, SU-8 2002 or ZPU core layer.

3. A silicon dioxide / polymer embedded waveguide based E according to claim 1 10 / E 01 A mode rotator, characterized in that: The refractive index of the polymer upper cladding material is less than that of the polymer core material, and the polymer upper cladding material is an EPO cladding, PMMA, PDMS or ZPU cladding.

4. An E based on silica / polymer embedded waveguide 10 / E 01 The preparation method of the mode rotator comprises the following steps: 1) growing a dense 12-18 μm thick silicon dioxide lower cladding layer (21) on a silicon substrate (1); 2) evaporating a metal aluminum layer (51) on the silicon dioxide lower cladding layer (21); 3) Spin-coating a layer of photoresist on the metal aluminum layer (51), and transferring the pattern on the mask plate having the same square groove structure and size as the polymer core layer (3) to be prepared to the metal aluminum layer (51) through ultraviolet exposure and development, thereby forming an aluminum mask (52); 4) etching the silicon dioxide lower cladding layer (21) using an aluminum mask (52) by an ICP etching method to obtain a silicon dioxide lower cladding layer (22) with a protrusion, wherein the structure and size of the protrusion are the same as the structure and size of the square groove to be prepared, and then removing the aluminum mask (52); 5) Spin-coating a photoresist mask layer material on the silicon dioxide lower cladding layer (22) with the protrusions, and naturally cooling and curing after pre-baking to form a flat photoresist mask layer (61); 6) transferring the pattern on the mask plate having the same structure as or a complementary structure to the polymer core layer (3) to be prepared onto the photoresist mask layer (61) through ultraviolet lithography, development, and post-baking, thereby forming a photoresist mask (62) having a complementary structure to the polymer core layer (3); 7) etching the protruding silicon dioxide lower cladding layer (22) not protected by the photoresist mask (62) again by an ICP etching method to form a silicon dioxide lower cladding layer (2) with a groove structure, wherein the groove structure has the same structure and size as the polymer core layer (3) to be prepared, and then removing the photoresist mask (62); 8) Spin coating a polymer core layer material on the silicon dioxide lower cladding layer (2) with a groove structure, and naturally cool and solidify after pre-baking. The polymer core layer material fills the groove structure formed in step 7), and also forms a 0-5 μm polymer flat layer (4) on the upper surface of the silicon dioxide lower cladding layer (21) and the groove structure; 9) etching away the polymer flat layer (4) by an ICP etching method to obtain a polymer core layer (3) in the SiO2 lower cladding layer (2), wherein the upper surface of the polymer core layer (3) is located in the same plane as the upper surface of the SiO2 lower cladding layer (2); 10) Spin-coating a polymer upper cladding layer (7) on the upper surface of the polymer core layer (3) and the silicon dioxide lower cladding layer (2) after etching away the polymer flat plate layer (4), heating and curing, and then cooling naturally to prepare an E based on silicon dioxide / polymer embedded waveguide. 10 / E 01 Mode Rotator.

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