Planar optical waveguide, manufacturing method and optical chip

Abstract

The invention provides a planar optical waveguide, a manufacturing method of the planar optical waveguide, an optical chip and optical communication equipment, and the structure of the planar optical waveguide comprises a core layer which comprises a waveguide structure; the coating layer coats the core layer, and the refractive index of the coating layer is different from that of the core layer; wherein the coating layer is internally provided with at least one scribed line, and on the substrate, the projection of the scribed line is parallel to the projection of the waveguide in the waveguide structure. According to the invention, at least one side of the waveguide is provided with the scribed line to extrude the waveguide in the core layer, so that the stress in the direction parallel to the substrate and the stress in the direction perpendicular to the substrate are balanced, the birefringence is reduced, and the performance of the device is improved.

Description

Technical Field

[0001] The present application relates to the field of semiconductors and optoelectronic integration, and in particular to a planar optical waveguide, a method for manufacturing a planar optical waveguide, an optical chip, and an optical communication device. Background Art

[0002] In the field of optical technology, all kinds of single-form optical components are currently moving towards integrated optics. Planar optical waveguides are basic components that integrate different optical modules on the same substrate to form integrated optical circuits. Planar optical waveguides reduce the size and number of packaging times, and have the advantages of low cost, high performance, and high-density device integration. They help to achieve the integration and large-scale production of optical communication components, and are an essential component of optical fiber communication systems.

[0003] However, in planar optical waveguides, due to the waveguide geometric structure and residual thermal stress during the manufacturing process, birefringence will occur in the waveguide in the integrated optical circuit, limiting the application of planar optical waveguides. Summary of the invention

[0004] The present application provides a planar optical waveguide and a method for manufacturing the planar optical waveguide, using laser to form a scribed line inside a cladding layer in the planar optical waveguide to balance the stress of the planar optical waveguide and reduce birefringence.

[0005] In the first aspect, a planar optical waveguide is provided, which is arranged on a substrate in order from bottom to top: a core layer, including a waveguide structure; a cladding layer, which covers the core layer, and the refractive index of the cladding layer is different from that of the core layer; wherein at least one scribed line is arranged inside the cladding layer, and on the substrate, the projection of the scribed line is parallel to the projection of the waveguide in the waveguide structure, and the projection of the scribed line is spaced apart from the projection of the waveguide. Thus, by setting the scribed line, the waveguide in the core layer can be squeezed without affecting the light transmission in the waveguide, the stress in the X direction and the Y direction can be balanced, the birefringence of the planar optical waveguide can be reduced, and the device performance can be improved. wherein, the X direction refers to the direction parallel to the substrate, and the Y direction refers to the direction perpendicular to the substrate.

[0006] In combination with the first aspect, in some implementations of the first aspect, the at least one scribed line includes a first scribed line and a second scribed line, the waveguide structure includes a first waveguide, and a projection of the first scribed line and a projection of the second scribed line are respectively located on opposite sides of the projection of the first waveguide, thereby forming extrusion on both sides of the waveguide to further balance stresses in the X direction and the Y direction.

[0007] In combination with the first aspect, in certain implementations of the first aspect, the cross-sectional morphology of the scribed line is different from the cross-sectional morphology of the cladding layer. Thus, stress changes are achieved through the structure of the scribed line, and the waveguide is squeezed. In some cases, the difference between the morphology of the scribed line and the morphology of the cladding layer can be reflected by the refractive index, and the refractive index of the scribed line is different from the refractive index of the cladding layer.

[0008] In combination with the first aspect, in certain implementations of the first aspect, the scribed line is formed by femtosecond laser ablation, and the focus of the femtosecond laser is aligned with the interior of the cladding layer. By ablating the cladding layer with a high-energy femtosecond laser, multi-photon absorption can occur inside the cladding layer, and a large number of free electrons are generated to form plasma. The expansion of the plasma leads to high temperature and high pressure in the ablation area of ​​the material, resulting in a micro-explosion phenomenon, thereby forming a morphological structural change inside the cladding layer. In some cases, in the scribed line structure formed by the micro-explosion phenomenon, there is a morphological structural change from the center of the scribed line to the edge. The morphological structural change can be reflected by the change in refractive index from the center of the scribed line to the edge.

[0009] In combination with the first aspect, in certain implementations of the first aspect, on the substrate, the spacing between the projection of the scribed line and the projection of the waveguide is greater than or equal to 10 μm and less than or equal to 90 μm. Thus, by determining the distance between the scribed line and the waveguide, precise control of stress balance is achieved. In some implementations, the spacing between the projection of the scribed line and the projection of the waveguide is greater than or equal to 20 μm and less than or equal to 40 μm, further achieving stress balance in the X direction and the Y direction.

[0010] In combination with the first aspect, in some implementations of the first aspect, the waveguide structure is a beam splitter, the beam splitter includes an input waveguide and N output waveguides, and 2N scribed lines corresponding to the N output waveguides are arranged inside the cladding layer, where N is a positive integer. This balances the stress in the sensitive area of ​​the beam splitter, reduces birefringence, and improves the performance of the beam splitter.

[0011] In combination with the first aspect, in some implementations of the first aspect, the waveguide structure is a Mach-Zehnder interferometer structure, the Mach-Zehnder interferometer structure includes two beam splitting arm waveguides, and four scribed lines corresponding to the two beam splitting arm waveguides are arranged inside the cladding layer, thereby balancing the stress in the sensitive area of ​​the Mach-Zehnder interferometer, reducing birefringence, and improving performance.

[0012] In combination with the first aspect, in some implementations of the first aspect, a balancing layer is further provided on the cladding layer, and the thermal expansion coefficient of the balancing layer is greater than the thermal expansion coefficient of the cladding layer. By continuing to grow a balancing layer with a larger thermal expansion coefficient on the cladding layer, the stress in the X direction is reduced, so that the stress in the X direction is consistent with the stress in the Y direction, the birefringence is reduced, and the device performance is improved. In some implementations, the thermal expansion coefficient of the balancing layer is greater than or equal to 0.5×10-6 / K, less than or equal to 5×10 -6 / K.

[0013] In combination with the first aspect, in some implementations of the first aspect, the thickness of the balancing layer is greater than or equal to 0.5 μm and less than or equal to 30 μm. By determining the thickness of the balancing layer, precise control of stress balance can be achieved.

[0014] In some implementations, the thickness of the balancing layer is greater than or equal to 0.5 μm and less than or equal to 3.5 μm, further achieving stress balance in the X direction and the Y direction.

[0015] In a second aspect, a method for manufacturing a planar optical waveguide is provided, which is used to prepare the above-mentioned first aspect and any possible optical waveguide structure in the first aspect.

[0016] In a third aspect, a chip is provided, the chip including an optical waveguide structure, the optical waveguide structure adopts the above-mentioned first aspect and any possible optical waveguide structure in the first aspect, wherein the optical chip also includes any one of an optical switch, an optical splitter, an optical amplifier and an optical attenuator.

[0017] In a fourth aspect, an optical module is provided, comprising a circuit board, an optical transmitting component and / or an optical receiving component, and the chip in the third aspect.

[0018] In a fifth aspect, an optical communication device is provided, comprising at least one optical link, wherein the optical module according to the fourth aspect is arranged in the optical link. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of a preparation process of a planar optical waveguide provided in an embodiment of the present application.

[0020] Figure 2 It is a schematic diagram of the structure of a planar optical waveguide provided in an embodiment of the present application.

[0021] Figure 3 It is a schematic diagram of the relationship between the projection spacing of a scribed line and a waveguide and the difference in refractive index provided in an embodiment of the present application.

[0022] Figure 4 It is a schematic diagram of the structure of a planar optical waveguide provided in an embodiment of the present application.

[0023] Figure 5 This is a schematic diagram of the relationship between the thickness of a balancing layer and the difference in refractive index provided in an embodiment of the present application.

[0024] Figure 6 It is a schematic diagram of the structure of a planar optical waveguide provided in an embodiment of the present application. DETAILED DESCRIPTION

[0025] The technical solution in this application will be described below in conjunction with the accompanying drawings.

[0026] In the following, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features.

[0027] References to "one embodiment" or "some embodiments" etc. described in this specification mean that a particular feature, structure or characteristic described in conjunction with the embodiment is included in one or more embodiments of the present application. Thus, the phrases "in one embodiment", "in some embodiments", "in some other embodiments", "in some other embodiments", etc. that appear at different places in this specification do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. The terms "including", "comprising", "having" and their variations all mean "including but not limited to", unless otherwise specifically emphasized in other ways.

[0028] In the description of the embodiments of the present application, the terms "upper", "lower", "vertical", "horizontal", etc. indicate orientations or positional relationships that are defined relative to the orientations or positions of the components schematically placed in the drawings. It should be understood that these directional terms are relative concepts. They are used for relative descriptions and clarifications, rather than indicating or implying that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. They may change accordingly according to changes in the orientations of the components placed in the drawings, and therefore cannot be understood as limitations on the present application.

[0029] The terms "including" and "having" and any variations thereof in the embodiments of the present application shown below are intended to cover non-exclusive inclusions. For example, a process, method, system, product or apparatus comprising a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units that are not explicitly listed or inherent to these processes, methods, products or apparatuses.

[0030] In the embodiments of the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions, and embodiments or designs described as "exemplary" or "for example" should not be interpreted as being more preferred or more advantageous than other embodiments or designs. The use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way for easy understanding.

[0031] In the embodiments of the present application, the same reference numerals are used to represent the same components or parts. In addition, the various parts in the drawings are not drawn to scale, and the sizes and dimensions of the parts shown in the drawings are only exemplary and should not be understood as limiting the present application.

[0032] In the field of optical technology, all kinds of single-form optical components are currently moving towards integrated optics. That is, the optical path of the waveguide chip is manufactured using integrated circuit technology, and the various functions of conventional discrete optical components are integrated into the surface of the same optical substrate, completing the optical information processing capabilities of a large optical system composed of multiple discrete optical components, and realizing functions such as light wave signal production and detection, optical power distribution, optical switching, and optical filtering. Since most functional structures are on the same optical substrate and the main structure is the optical waveguide channel, the technology is called planar light waveguide technology (Planar Lightwave Circuit, PLC). Planar light waveguides reduce the size and the number of packaging times, and have the advantages of low cost, high performance, and high-density device integration. They help to achieve the integration and large-scale production of optical communication components, and are an essential component of optical fiber communication systems.

[0033] Figure 1 Schematic diagram of a preparation process of a planar optical waveguide provided in an embodiment of the present application. The planar optical waveguide is a layered structure, and its manufacturing process may include: Figure 1 Middle (a), growing core layer; Figure 1 (b), photolithography, dry etching or wet etching is performed on the core layer to obtain a waveguide structure; Figure 1 In (c), a cladding layer is grown, or it can also be understood as an upper cladding layer.

[0034] However, in planar optical waveguides, the waveguide geometry is not completely symmetrical. In the core layer, there is a difference between the direction X parallel to the substrate and the direction Y perpendicular to the substrate of the planar optical waveguide. In addition, in the process of growing the cladding layer, it is usually necessary to dope boron (B) in the cladding layer to reduce the softening temperature of the cladding layer, and adopt an annealing process to ensure that the junction between the core layer and the cladding is completely filled to improve performance. In addition, it is also necessary to dope phosphorus (P) and germanium (Ge) in the cladding layer to ensure that the refractive index of the core layer and the cladding layer is different, so as to confine the light to the waveguide structure of the core layer for transmission. The above doping process will cause the expansion rate of the cladding layer to increase, which does not match the expansion rate of the substrate. After the annealing process is adopted, the stress in the X direction and the Y direction in the core layer will be inconsistent due to the introduction of thermal stress.

[0035] In summary, due to the waveguide geometry and the residual thermal stress during the manufacturing process, the stress in the X direction and the stress in the Y direction in the core layer will be inconsistent. Optically, the refractive index is related to the stress. Specifically in a planar optical waveguide, the stress and the refractive index have the following optical relationship:

[0036] n x =n0-B1S x -B2S y

[0037] n y =n0-B1S y -B2S x

[0038] Among them, n x is the refractive index in the X direction, n y is the refractive index in the Y direction, S x is the stress in the X direction, S y is the stress in the Y direction, n0 is the material refractive index of the planar optical waveguide, and B1 and B2 are constants.

[0039] From the above, we can see that due to S x With S y Not equal, so n x With n y The birefringence phenomenon occurs when the polarization is not equal. Especially for devices with large polarization dependent loss (PDL) such as gratings and Mach-Zehnder-Interferometers (MZI), they are particularly sensitive to birefringence, which greatly affects their performance and limits the application of planar optical waveguides.

[0040] Based on the above problems, the embodiments of the present application provide a planar optical waveguide and a method for manufacturing the planar optical waveguide, using laser to form lines inside the cladding layer in the planar optical waveguide to balance the stress of the planar optical waveguide and reduce birefringence.

[0041] Figure 2 It is a schematic diagram of the structure of a planar optical waveguide provided in an embodiment of the present application. Figure 2 (a) shows a cross section of a planar optical waveguide, which is arranged on a substrate from bottom to top:

[0042] The core layer 210 includes a waveguide structure.

[0043] The cladding layer 220 covers the core layer, wherein the refractive index of the cladding layer 220 is different from that of the core layer 210 , thereby confining light to be transmitted in the waveguide structure of the core layer 210 .

[0044] Among them, at least one scribed line is arranged inside the cladding layer 220, and on the substrate, the projection of the scribed line is parallel to the projection of the waveguide in the waveguide structure, and there is a gap between the projection of the scribed line and the projection of the waveguide. Therefore, by setting the scribed line, the waveguide in the core layer can be squeezed without affecting the light transmission in the waveguide, the stress in the X direction and the Y direction can be balanced, the birefringence of the planar optical waveguide can be reduced, and the device performance can be improved.

[0045] In some implementations, at least one scribe line may include a first scribe line 231 and a second scribe line 232, and the projection of the first scribe line 231 and the projection of the second scribe line 232 are respectively located on opposite sides of the projection of the first waveguide in the waveguide structure, thereby forming extrusion on both sides of the waveguide to further balance the stress in the X direction and the Y direction.

[0046] In some implementations, the cross-sectional morphology of the ruled line is different from the cross-sectional morphology of the cladding layer 220, thereby achieving stress change through the structure of the ruled line, and squeezing the waveguide. In some cases, the difference between the morphology of the ruled line and the morphology of the cladding layer 220 can be reflected by the refractive index, and the refractive index of the ruled line is different from the refractive index of the cladding layer.

[0047] In some implementations, the scribed lines can be formed by femtosecond laser ablation, with the focus of the femtosecond laser being aligned with the interior of the cladding. By ablating the cladding with a high-energy femtosecond laser, multiphoton absorption can occur inside the cladding, generating a large number of free electrons to form plasma, and the expansion of the plasma leads to high temperature and high pressure in the ablated area of ​​the material, resulting in a micro-explosion phenomenon, thereby forming a morphological structural change inside the cladding. In some cases, in the scribed line structure formed by the micro-explosion phenomenon, there is a morphological structural change from the center of the scribed line to the edge. The morphological structural change can be reflected by the change in refractive index from the center of the scribed line to the edge.

[0048] and Figure 2 In (a), Figure 2 (b) and Figure 2 (c) shows the specific positions of the two lines.

[0049] Figure 2 (b) corresponds to the case where the waveguide structure is a beam splitter structure. The beam splitter may include an input waveguide and N output waveguides. The input waveguide and the N output waveguides are optically connected, and N is a positive integer. In some cases, the N output waveguides may be parallel to each other and form a grating, and N is a positive integer greater than or equal to 2. Figure 2 As shown in (b), 2N scribed lines corresponding to the N waveguides can be set in the cladding layer to balance the stress in the sensitive area of ​​the beam splitter, reduce birefringence, and improve the performance of the beam splitter.

[0050] Figure 2(c) corresponds to the case where the waveguide structure is a Mach-Zehnder interferometer structure. The Mach-Zehnder interferometer structure may include two beam splitting arm waveguides, such as Figure 2 As shown in (c), four lines corresponding to the two beam splitting arm waveguides can be provided in the cladding layer, thereby balancing the stress in the sensitive area of ​​the Mach-Zehnder interferometer, reducing birefringence, and improving performance.

[0051] In some implementations, the spacing between the projection of the scribed line and the projection of the waveguide can be controlled within a range of greater than or equal to 10 μm and less than or equal to 90 μm, thereby achieving precise control of stress balance by determining the distance between the scribed line and the waveguide. Figure 3 It is a schematic diagram of the relationship between the projection spacing of the scribed line and the projection spacing of the waveguide and the difference in refractive index provided in an embodiment of the present application. As a specific example of achieving regulation, on a substrate, the projection spacing of the scribed line and the waveguide can be regulated within a range of greater than or equal to 20 μm and less than or equal to 40 μm. When the projection spacing of the scribed line and the waveguide is 30 μm, the birefringence is controlled at the order of E-6. With further precise regulation, the difference between the refractive index in the X direction and the refractive index in the Y direction can also be regulated to close to 0. Among them, the X direction refers to the direction parallel to the substrate, and the Y direction is the direction perpendicular to the substrate. It should be understood that, Figure 3 The situation in the figure is only an example, and the spacing between the projection of the scribed line and the projection of the waveguide is determined by the size of the specific scribed line, or the spot size and energy of the laser used.

[0052] Figure 4 Schematic diagram of the structure of a planar optical waveguide provided in an embodiment of the present application. Figure 4 As shown, the planar optical waveguide is on the substrate, including the following arranged in sequence from bottom to top:

[0053] The core layer 410 includes a waveguide structure.

[0054] The cladding layer 420 covers the core layer, wherein the refractive index of the cladding layer 420 is different from that of the core layer 410 , thereby confining light to be transmitted in the waveguide structure of the core layer 410 .

[0055] The balancing layer 430 has a thermal expansion coefficient greater than that of the cladding layer.

[0056] The specific material of the above-mentioned balancing layer is determined in combination with the specific design. For example, the material of the balancing layer can be a semiconductor material or a metal material. In some implementations, the material of the balancing layer is one of silicon, silicon nitride, silicon dioxide, or doped silicon dioxide. In some implementations, the thermal expansion coefficient of the balancing layer can be determined to be greater than or equal to 0.5×10 -6 / K, less than or equal to 5×10 -6 / K range.

[0057] In such Figure 4 In the method shown, by continuing to grow a balancing layer with a large thermal expansion coefficient on the cladding layer, the stress in the X direction is reduced, so that the stress in the X direction is consistent with the stress in the Y direction, the birefringence is reduced, and the device performance is improved.

[0058] In some implementations, the thickness of the balancing layer is greater than or equal to 0.3 μm and less than or equal to 30 μm. By determining the thickness of the balancing layer, precise control of stress balance can be achieved. Figure 5 : This is a schematic diagram of the relationship between the thickness of a balancing layer and the difference in refractive index provided in an embodiment of the present application. Taking silicon nitride as an example, when the thickness of the balancing layer is greater than or equal to 0.5 μm and less than or equal to 3.5 μm, the difference Δn between the refractive index in the X direction and the refractive index in the Y direction of the planar optical waveguide can be controlled within -4.0×10 -5 to 1.0×10 -5 In some implementations, the thickness of the balancing layer is greater than or equal to 1 μm and less than or equal to 1.5 μm. Correspondingly, the difference Δn between the refractive index in the X direction and the refractive index in the Y direction of the planar optical waveguide can be controlled to be -0.5×10 -5 to 0.5×10 -5 The birefringence is controlled at the level of E-6. With further precise control, the difference between the refractive index in the X direction and the refractive index in the Y direction can be controlled to be close to 0.

[0059] It should be understood that the material used is silicon nitride only for example. Figure 5 The thickness range described in the same manner is also applicable to other materials having a thermal expansion coefficient of the same order of magnitude as silicon nitride, such as other materials having a thermal expansion coefficient of E-6 / K to E-5 / K.

[0060] Figure 6 Schematic diagram of the structure of a planar optical waveguide provided in an embodiment of the present application. Figure 6 As shown, in some implementations, a balancing layer can be further provided on the cladding layer on the basis of providing scribed lines in the cladding layer, so that the scribed lines can be used to balance the stress difference in the X direction and the Y direction caused by the waveguide geometric structure, and the balancing layer can also be used to balance the residual thermal stress in the manufacturing process, so as to further reduce the birefringence and improve the device performance.

[0061] The specific setting of the engraved lines 631 and 632 is Figure 2 The middle scale lines 231 and 232 are similar and will not be described in detail here. Figure 4 The middle balancing layer 440 is the same and will not be described again.

[0062] In addition, the present application also provides a preparation method as Figure 2 , Figure 4 and Figure 6 The method embodiment of the planar optical waveguide shown in the figure corresponds to the aforementioned structure, so the parts not described in detail can refer to the aforementioned parts.

[0063] As a preparation Figure 2 The method of the planar optical waveguide shown in the figure can use a laser to ablate the cladding layer at least once to form a Figure 2 At least two scribed lines as described in the above are formed. The focus of the laser is aligned with the inside of the cladding layer. On the substrate, the projection of the scribed line formed by laser ablation is parallel to the projection of the waveguide in the waveguide structure, and the projection of the scribed line is spaced apart from the projection of the waveguide.

[0064] The power, polarization direction, and spot size of the laser are determined according to the actual situation. In some implementations, a high-energy femtosecond laser can be used to ablate the cladding layer, so that multi-photon absorption occurs inside the cladding layer, a large number of free electrons are generated to form plasma, and the expansion of the plasma leads to high temperature and high pressure in the ablation area of ​​the material, resulting in a micro-explosion phenomenon, and a morphological structure change occurs inside the cladding layer.

[0065] As a preparation Figure 4 The method of the planar optical waveguide shown in the figure can further grow a balancing layer on the cladding layer in a planar structure including a substrate, a core layer and a cladding layer arranged sequentially from bottom to top. The core layer includes a waveguide structure, the cladding layer covers the core layer, and the refractive index of the cladding layer is different from the refractive index of the core layer. The thermal expansion coefficient of the balancing layer is greater than that of the cladding layer.

[0066] The method of growing the balancing layer is determined according to the actual situation. For example, chemical vapor deposition can be used, and this application does not limit this. In some implementations, the thermal expansion coefficient of the balancing layer is greater than or equal to 0.5×10 -6 / K, less than or equal to 5×10 -6 / K.

[0067] In some implementations, the thickness of the balancing layer is greater than or equal to 0.3 μm and less than or equal to 30 μm. In some implementations, the thickness of the balancing layer is greater than or equal to 0.5 μm and less than or equal to 3.5 μm. Correspondingly, the difference Δn between the refractive index in the X direction and the refractive index in the Y direction of the planar optical waveguide can be controlled within -4.0×10 -5 to 1.0×10 -5In some implementations, the thickness of the balancing layer is greater than or equal to 1 μm and less than or equal to 1.5 μm. Correspondingly, the difference Δn between the refractive index in the X direction and the refractive index in the Y direction of the planar optical waveguide can be controlled to be -0.5×10 -5 to 0.5×10 -5 The birefringence index is controlled to be between E-6 and E-7, that is, the birefringence index is controlled to be in the order of E-6. The specific material of the balancing layer is determined in combination with the specific design. For example, the material of the balancing layer can be a semiconductor material or a metal material. In some implementations, the material of the balancing layer is one of silicon, silicon nitride, silicon dioxide, or doped silicon dioxide.

[0068] In addition, the embodiment of the present application further provides a chip, the chip includes a planar optical waveguide, the planar optical waveguide is as follows Figure 2 , Figure 4 and Figure 6 The planar optical waveguide shown.

[0069] In some implementations, the chip may further include an optical switch and / or an optical splitter, and the chip is used to schedule optical signals. Specifically, scheduling optical signals may refer to branch transmission of optical signals or distribution of optical signals.

[0070] In some implementations, the chip may further include an optical amplifier or an optical attenuator, and the chip is used to adjust the power of the optical signal. Specifically, the optical amplifier may be used to amplify the power of the optical signal, and the optical attenuator may be used to reduce the power of the optical signal.

[0071] In addition, the embodiment of the present application further provides an optical module. The optical module includes a circuit board, an optical transmitting component and / or an optical receiving component and the above optical chip. The optical module can be used to realize the conversion between optical signals and electrical signals.

[0072] In some implementations, the optical module includes a circuit board, an optical transmission component, and an optical chip, wherein the circuit board is electrically connected to the optical transmission component, the optical transmission component is used to generate an optical signal according to an electrical signal, and the optical chip is used to process the generated optical signal. The processing performed by the optical chip on the generated optical signal may be power modulation of the optical signal or scheduling of the optical signal.

[0073] In some implementations, the optical module includes a circuit board, an optical receiving component, and an optical chip, wherein the circuit board is electrically connected to the optical receiving component, the optical receiving component is used to convert an optical signal into an electrical signal, and the optical chip is used to process the received optical signal. The processing performed by the optical chip on the received optical signal may be power modulation or scheduling of the optical signal.

[0074] In some implementations, the optical module includes a circuit board, an optical receiving component, an optical transmitting component and an optical chip, and the specific functions of the circuit board, the optical receiving component, the optical transmitting component and the optical chip are consistent with those described above and are not described in detail here. The optical module is used to send and receive optical signals at the same time.

[0075] In some implementations, the optical module further includes a housing, and the housing is used to accommodate a circuit board, an optical emitting component and / or an optical receiving component, and the optical chip.

[0076] In some implementations, the optical module further includes an optical interface, which is used to transmit optical signals.

[0077] In some implementations, the optical module further includes an electrical interface for transmitting electrical signals.

[0078] In addition, an embodiment of the present application further provides an optical communication device, which may include one or more optical links, wherein the optical link may specifically refer to an optical fiber, wherein the optical link may be provided with the above optical module.

[0079] In some implementations, the optical communication device is an optical switch.

[0080] In some implementations, the optical communication device is an optical modem.

[0081] Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0082] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A planar optical waveguide, characterized in that: On the substrate, the following are arranged in order from bottom to top: a core layer, including a waveguide structure; A cladding layer, covering the core layer, wherein the refractive index of the cladding layer is different from that of the core layer; At least one scribed line is arranged inside the cladding layer, and on the substrate, a projection of the scribed line is parallel to a projection of a waveguide in the waveguide structure, and there is a distance between the projection of the scribed line and the projection of the waveguide.

2. The planar optical waveguide according to claim 1, characterized in that The at least one scribed line includes a first scribed line and a second scribed line, the waveguide structure includes a first waveguide, and a projection of the first scribed line and a projection of the second scribed line are respectively located on opposite sides of the projection of the first waveguide.

3. The planar optical waveguide according to claim 1 or 2, characterized in that: The cross-sectional morphology structure of the score line is different from the cross-sectional morphology structure of the coating layer.

4. The planar optical waveguide according to any one of claims 1 to 3, characterized in that The scribe lines are formed by femtosecond laser ablation, and the focus of the femtosecond laser is aligned with the interior of the cladding layer.

5. The planar optical waveguide according to any one of claims 1 to 4, characterized in that: On the substrate, a distance between a projection of the scribed line and a projection of the waveguide is greater than or equal to 10 μm and less than or equal to 90 μm.

6. The planar optical waveguide according to any one of claims 1 to 5, characterized in that The waveguide structure is a beam splitter, which includes an input waveguide and N output waveguides. 2N scribed lines corresponding to the N output waveguides are arranged inside the cladding layer, wherein N is a positive integer.

7. The planar optical waveguide according to any one of claims 1 to 6, characterized in that: The waveguide structure is a Mach-Zehnder interferometer structure, which includes two beam-splitting arm waveguides. Four scribed lines corresponding to the two beam-splitting arm waveguides are arranged inside the cladding layer.

8. The planar optical waveguide according to any one of claims 1 to 7, characterized in that A balancing layer is further arranged on the cladding layer, and the thermal expansion coefficient of the balancing layer is greater than the thermal expansion coefficient of the cladding layer.

9. The planar optical waveguide according to claim 8, characterized in that The thickness of the balancing layer is greater than or equal to 0.3 μm and less than or equal to 30 μm.

10. A method for manufacturing a planar optical waveguide, characterized in that: Used for preparing a planar optical waveguide as claimed in any one of claims 1 to 9.

11. An optical chip, characterized in that: The optical chip comprises the planar optical waveguide according to any one of claims 1 to 9, wherein the optical chip further comprises any one of an optical switch, an optical splitter, an optical amplifier and an optical attenuator.

12. An optical module, characterized in that: It comprises a circuit board, a light emitting component and / or a light receiving component and the optical chip as claimed in claim 11.

13. An optical communication device, characterized in that: The optical link comprises at least one optical link, wherein the optical module according to claim 12 is arranged in the optical link.

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