Optical waveguide structure based on glass substrate and preparation method

Abstract

The invention relates to the technical field of optical waveguides, and discloses an optical waveguide structure based on a glass substrate and a preparation method, the optical waveguide structure comprises the glass substrate and at least one optical waveguide, the optical waveguide is located in the glass substrate, the optical waveguide is determined based on a modified area in the glass substrate, and the modified area is located in the glass substrate. The modified area is formed by laser modification in the glass substrate by laser modification equipment, and the refractive index of the modified area is greater than that of an unmodified substrate area in the glass substrate. According to the technical scheme provided by the invention, high-density wiring of the optical waveguide and low-loss and high-bandwidth optical interconnection transmission can be realized.

Description

Technical Field

[0001] This application relates to the field of optical waveguide technology, and in particular to an optical waveguide structure based on a glass substrate and its fabrication method. Background Technology

[0002] Currently, in the fields of high-speed optical interconnects and advanced packaging, co-packaging optics technology has been widely used in optical communication, high-performance computing, and artificial intelligence because it can integrate optical engines and computing chips on the same substrate at high density.

[0003] Traditional resin substrates cannot achieve low-loss, high-bandwidth optical interconnects, but can only achieve high-loss, low-bandwidth electrical interconnects. Therefore, the industry has introduced CPO (Co-Packaged Optics) technology to place the optical engine as close as possible to the switch chip, extending the optical path and shortening the circuit, thereby improving signal transmission efficiency to some extent. However, since the chip size is usually small, and thousands of optical fibers need to be directly connected to the optical engine, a larger peripheral size is required to meet the wiring density, making it difficult to miniaturize the entire module. Wiring density and space constraints have become key bottlenecks restricting optical signal transmission and electrical interconnection.

[0004] Therefore, how to achieve more efficient optical signal transmission and electrical interconnection in optical waveguides has become a key research focus in the field of optical waveguides. Summary of the Invention

[0005] This application provides an optical waveguide structure based on a glass substrate and its fabrication method, which can realize high-density wiring of the optical waveguide and low-loss, high-bandwidth optical interconnect transmission.

[0006] The first aspect of this application provides an optical waveguide structure based on a glass substrate, the optical waveguide structure including a glass substrate and at least one optical waveguide located inside the glass substrate, wherein: the optical waveguide is determined based on a modified region in the glass substrate, the modified region being formed by laser modification of the glass substrate using a laser modification device, and the refractive index of the modified region being greater than that of an unmodified substrate region in the glass substrate.

[0007] In one embodiment, the optical waveguide is a three-dimensional waveguide; the three-dimensional waveguide includes modified regions located at different depths within the glass substrate.

[0008] In one embodiment, the laser modification apparatus includes a single laser source; the modification region is formed by irradiating a designated area inside the glass substrate with a beam of light from the single laser source.

[0009] In one embodiment, the laser modification device further includes a lens; the lens is used to adjust the focusing depth of the laser beam to form modification regions of different depths, wherein the modification regions of different depths are used to form a three-dimensional waveguide.

[0010] In one embodiment, the laser modification device includes multiple laser light sources; the modification area is formed by focusing the beams of the multiple laser light sources at a designated area inside the glass substrate and then irradiating it after focusing.

[0011] In one embodiment, the focusing depth of the beams of the plurality of laser light sources is adjusted to form modified regions of different depths, wherein the modified regions of different depths are used to form a three-dimensional waveguide.

[0012] In one embodiment, the routing shape of the optical waveguide is determined by the movement trajectory of the laser modification device relative to the glass substrate.

[0013] A second aspect of this application provides a method for fabricating an optical waveguide based on a glass substrate. The method includes: obtaining a pretreated glass substrate, and determining a laser modification device and a preset optical guide path based on a modification target, wherein the laser modification device includes one or more laser sources; using the laser modification device to perform laser modification on a designated area of ​​the glass substrate to form a modified area, wherein the refractive index of the modified area is greater than that of an unmodified substrate area in the glass substrate; and moving the laser modification device to extend the modified area along the preset optical guide path to form the optical waveguide.

[0014] A third aspect of this application provides a co-packaged optical component, the co-packaged optical component comprising the glass substrate-based optical waveguide structure as described in the first aspect above.

[0015] Using a glass substrate as the base, a laser modification device is used to modify a designated area within the substrate, making the refractive index of the modified area higher than that of the unmodified area. Optical waveguides are then directly formed from these continuously modified areas. By controlling the laser power, irradiation time, and trajectory, precise control over the refractive index, geometry, and three-dimensional wiring of the optical waveguide can be achieved. The laser modification precision can reach the micrometer or even sub-micrometer level, enabling high-density optical waveguide integration and three-dimensional wiring. Furthermore, due to the low scattering loss of the glass material itself, combined with refractive index optimization and geometric dimension control, optical signal transmission loss is significantly reduced, improving transmission and coupling efficiency, thus achieving low-loss, high-bandwidth optical interconnect transmission. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of a method for fabricating an optical waveguide based on a glass substrate, provided in one embodiment of this application. Figure 2(a) is a schematic diagram of a single-source planar waveguide fabrication according to an embodiment of this application; Figure 2(b) is a schematic diagram of a single-source three-dimensional waveguide fabrication according to an embodiment of this application; Figure 2(c) is a schematic diagram of a multi-source planar waveguide fabrication according to an embodiment of this application; Figure 2(d) is a schematic diagram of a three-dimensional waveguide fabrication with multiple light sources provided in an embodiment of this application.

[0018] Explanation of reference numerals in the attached figures 10-Laser source, 11-Glass substrate, 121-Planar waveguide, 122-Three-dimensional waveguide, 200-Laser source, 201-Laser source, 21-Glass substrate, 221-Planar waveguide, 222-Three-dimensional waveguide. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0020] Furthermore, the use of terms such as "first," "second," etc., in this application is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of embodiments in this application, unless otherwise stated, "multiple" means two or more. Additionally, the use of "based on" or "according to" implies openness and inclusiveness, because processes, steps, calculations, or other actions "based on" or "according to" one or more of the stated conditions or values ​​may in practice be based on additional conditions or beyond the stated values.

[0021] Against the backdrop of the rapid development of global artificial intelligence applications, traditional electrical interconnects are no longer sufficient to meet the demands for low latency and high bandwidth. Co-packaged optical technology has emerged to address this need, enabling high-density integration of optical engines and computing chips onto the same substrate to reduce electrical signal paths. Specifically, the optical engine converts electrical signals from the chip into optical signals for injection into the optical waveguide, or converts optical signals from the waveguide back into electrical signals for transmission to the chip, thus achieving optical signal transmission and electrical interconnection. In particular, using optical signals instead of electrical signals for long-distance, high-bandwidth signal transmission via optical waveguides can significantly improve signal transmission bandwidth and reduce power consumption, and has become a key path supporting applications such as artificial intelligence and high-performance computing.

[0022] Traditional resin substrates cannot achieve low-loss, high-bandwidth optical interconnects, only high-loss, low-bandwidth electrical interconnects. Therefore, the industry has introduced co-packaging optics technology to place the optical engine as close as possible to the switch chip, extending the optical path and shortening the circuit. Related technologies also incorporate glass substrates into co-packaging optics. Besides its excellent thermal and mechanical properties, glass can also function as an optical waveguide through special processing. Therefore, in an optical waveguide with a fiber-like structure, light can propagate along the integrated glass waveguide and efficiently couple into the optical fiber or silicon photonic chip. The introduction of glass substrates can solve problems related to warpage, heat dissipation, and interconnect density inherent in traditional substrates. However, one problem remains: the chip size is typically small, and directly connecting thousands of optical fibers to the optical engine requires a larger peripheral dimension to meet the wiring density. Therefore, miniaturization of the entire module remains an unattainable challenge, and wiring density and space constraints have become key bottlenecks restricting optical signal transmission and electrical interconnection. This application enables the realization of an optical waveguide of the same size as an optical fiber through a micron-scale optical waveguide path. By extending the optical path on a glass substrate, the glass-based optical waveguide can be directly optically coupled to the optical engine, achieving extremely high coupling efficiency and extremely low transmission loss.

[0023] In view of the above, one or more embodiments of this application provide an optical waveguide structure and fabrication method based on a glass substrate, which can solve the above problems. By using a laser modification device to directly write an optical waveguide of arbitrary shape with a micron-level optical path spacing in the glass substrate, high-density wiring of the optical waveguide is achieved. Furthermore, the optical path is extended on the glass substrate, so that the optical waveguide structure can be directly optically coupled to the photonic chip, thereby realizing low-loss, high-bandwidth optical interconnect transmission.

[0024] In a first aspect, one embodiment of this application provides an optical waveguide structure based on a glass substrate, the optical waveguide structure comprising a glass substrate and at least one optical waveguide, the optical waveguide being located inside the glass substrate, wherein: The aforementioned optical waveguide is determined based on a modified region in the aforementioned glass substrate. The modified region is formed by laser modification of the aforementioned glass substrate using a laser modification device. The refractive index of the modified region is greater than that of the unmodified substrate region in the aforementioned glass substrate.

[0025] In this embodiment, glass is used as the substrate and base material for fabricating the optical waveguide. Specifically, the optical waveguide, serving as a channel for optical signal transmission, is located inside the glass substrate and is used to confine the optical signal within a specific path, achieving efficient optical transmission. The optical waveguide is formed by regional modification of the glass substrate, using the glass substrate as the raw material for fabricating the optical waveguide. Through localized laser modification, the physical and chemical properties of a portion of the glass (the modified region) are precisely altered, such as by changing the refractive index. This modified region continuously forms channels, thus directly constituting the optical waveguide. Furthermore, electrical interconnects can be directly fabricated within the optical waveguide structure using mature through-glass via (TGV) technology, achieving true optoelectronic integration.

[0026] This can be understood as the optical waveguide and waveguide cladding being made of the same glass material, thus avoiding problems such as interfacial stress and delamination caused by mismatched properties such as thermal expansion coefficients between different materials. Compared to traditional technologies that use different materials to fabricate optical waveguide structures, optical waveguides based on modified regions of a glass substrate exhibit higher stability and reliability. Furthermore, glass materials have low scattering loss, allowing for lower transmission loss when using glass to fabricate waveguides. In addition, compared to the multi-step fabrication process of traditional methods involving laser pretreatment, chemical etching, cleaning and drying, material filling, and curing, directly fabricating optical waveguides in a glass substrate using laser equipment significantly reduces the production steps and cycle time, resulting in higher fabrication efficiency and lower production costs.

[0027] In this embodiment, a portion of a glass substrate is laser-modified using a laser modification device, and the continuous modified region forms an optical waveguide. Specifically, laser modification is typically achieved through thermal and chemical modification. Physical modification can be understood as using localized heat generated by the laser to create a melting or semi-molten state in the focused area, followed by cooling to form a change in refractive index. Chemical modification can be understood as using high-energy particles generated by the laser to break the chemical bonds of molecules in the irradiated area, thereby causing a change in refractive index. By irradiating a designated area of ​​the glass substrate with a laser using the laser modification device, thermal and chemical modification occur in the designated area, causing a change in the refractive index and creating a refractive index difference with the unmodified area. The area where the refractive index changes is considered the modified area. By modifying any continuous region of the glass substrate, optical waveguides with arbitrary routing and shapes can be realized.

[0028] In this embodiment, the degree of change in refractive index is generally related to the irradiation time and laser power. A higher refractive index results in better transmission performance of the optical waveguide. Generally, higher laser power leads to a higher refractive index in the modified region. However, excessive laser power can cause laser modification in non-irradiated areas, thus requiring careful control of the laser power. Furthermore, a longer laser irradiation time results in a more pronounced melting state in the irradiated area, making the refractive index difference between the modified region and other regions more significant. Further, a higher refractive index leads to a larger incident angle in the waveguide receiving relationship, thereby improving coupling efficiency, optimizing the optical field distribution, and resulting in higher transmission efficiency and lower transmission loss for the optical waveguide. Moreover, light propagates in the waveguide in the form of modes. The shape and number of modes are determined by the refractive index distribution, size, and operating wavelength of the waveguide. By controlling the lateral dimension and longitudinal depth of the modified region, the geometric dimensions of the waveguide can be changed, further optimizing the optical field distribution, improving the transmission efficiency of the optical waveguide, and reducing transmission loss.

[0029] In this embodiment, high-density optical waveguide structures can be achieved through laser modification. Because lasers can be precisely focused to specific locations within a glass substrate, with precision reaching the micrometer or even sub-micrometer level, optical waveguides can be formed in a very small space. Furthermore, more optical waveguides can be integrated on the same substrate, enabling high-density wiring. Moreover, by controlling the laser's trajectory, optical waveguide paths of arbitrary shapes can be directly formed, including straight lines, curves, and three-dimensional paths. This flexibility allows for complex wiring within a limited space. In addition, laser modification can not only form in-plane optical waveguides but also achieve three-dimensional wiring. By forming modified regions at different depths within the glass substrate, a three-dimensional optical waveguide network can be constructed, further improving the integration of the optical waveguide structure. This high-density optical waveguide structure not only improves optical signal transmission capabilities and system integration but also meets the demands of modern optical communication and high-performance computing for miniaturization, high bandwidth, and low power consumption.

[0030] Based on the above ideas, the technical solution provided in this embodiment of the application uses a glass substrate as the base. A laser modification device is used to modify a designated area within the substrate, making the refractive index of the modified area higher than that of the unmodified area. The continuously modified areas directly form an optical waveguide. By adjusting the laser power, irradiation time, and movement trajectory, precise control of the optical waveguide's refractive index, geometry, and three-dimensional wiring can be achieved. The laser modification accuracy can reach the micrometer or even sub-micrometer level, enabling high-density optical waveguide integration and three-dimensional wiring. Furthermore, due to the low scattering loss of the glass material itself, combined with refractive index optimization and geometric size control, optical signal transmission loss is significantly reduced, improving transmission efficiency and coupling efficiency, achieving low-loss, high-bandwidth optical interconnect transmission.

[0031] In one embodiment, the aforementioned optical waveguide is a three-dimensional waveguide, comprising modified regions at different depths within a glass substrate, with multiple modified regions at different depths continuously forming the three-dimensional waveguide. As a three-dimensional optical waveguide, the three-dimensional waveguide differs from traditional two-dimensional planar waveguides. It not only propagates optical signals in a plane (e.g., horizontally) but also forms optical propagation paths in the vertical direction (i.e., the thickness direction of the glass substrate). This three-dimensional structure allows optical signals to be transmitted between different depths within the glass substrate, realizing more optical paths within a limited space and significantly improving the integration density of the optical waveguide. For example, in laser modification technology, multiple modified regions can be formed at different depths within the glass substrate by controlling the focusing depth of the laser to create a three-dimensional waveguide.

[0032] The technical solution provided in this embodiment of the application designs a three-dimensional waveguide structure based on a glass substrate, further improving the high integration of the waveguide structure wiring. By controlling the focusing depth of the laser modification equipment, continuous modification regions are formed at different depths inside the glass substrate to form a three-dimensional waveguide. Compared with traditional two-dimensional planar waveguides, three-dimensional waveguides break through the spatial limitations of planar wiring, enabling the simultaneous realization of horizontal and vertical optical signal transmission paths inside the glass substrate, significantly improving the integration density of the waveguide, and further adapting to the application requirements of high integration and miniaturized optical transmission devices in the fields of optical communication and high-performance computing.

[0033] In one embodiment, the laser modification device includes a single laser source, which provides a high-energy laser beam, and can be a continuous-wave laser or a pulsed laser. The modified region is formed by irradiating a designated area inside the glass substrate with the beam from the single laser source. By precisely controlling parameters such as the focusing position, intensity, and wavelength of the beam, local modification can be achieved inside the glass substrate so that the formed modified region meets the predetermined design requirements of the optical waveguide, such as the waveguide path, shape, and depth, thereby achieving the desired modification effect.

[0034] In this embodiment, the laser modification device further includes a lens; by adjusting the focusing depth of the laser beam from the laser source using the lens, the laser beam can be focused to different depths within the glass substrate to form modification regions of varying depths. Since the lens can achieve focusing precision at the micrometer level or even higher, the laser beam can form modification regions at any depth within the glass substrate. Furthermore, these modification regions of different depths can be connected by continuous laser irradiation to form a continuous three-dimensional optical waveguide path, i.e., a three-dimensional waveguide.

[0035] In this embodiment, complex three-dimensional waveguides can be designed by controlling the beam trajectory and focusing depth of a single laser source. Specifically, the focusing depth of the laser beam within the glass can be precisely controlled by changing the focal length of the lens or adjusting the distance between the lens and the glass substrate. For example, a long focal length lens can focus the beam to a deeper position, while a short focal length lens is suitable for modification near the surface. Optionally, laser modification can be performed using precise path planning and control algorithms to ensure the continuity and integrity of the optical waveguide. By controlling the laser beam trajectory and focusing depth, complex three-dimensional waveguides can be designed, enabling more optical paths to be implemented within a limited space, significantly improving the integration density of optical waveguide wiring.

[0036] The technical solution provided in this embodiment of the application uses a single laser source to irradiate a designated area inside a glass substrate, forming a modified region with a high refractive index, thereby realizing the fabrication of an optical waveguide. This technology utilizes the high energy and high-precision focusing capability of lasers to quickly and flexibly manufacture optical waveguides of arbitrary shapes and paths. It has advantages such as simplicity, efficiency, high precision, and no need for masks, making it suitable for various optical communication and optical interconnect applications. Simultaneously, by adjusting the focusing depth of the laser beam through a lens, modified regions of different depths are formed inside the glass substrate, achieving high-precision three-dimensional waveguide fabrication. This offers advantages such as high integration, complex optical path design, and high-efficiency transmission, making it suitable for various high-performance optical interconnect applications.

[0037] In one embodiment, the laser modification device includes multiple laser sources that can be independently controlled and emit beams in different directions. Optionally, these laser sources can be controlled independently or work collaboratively to achieve more complex optical waveguide structures. The modified region is formed by focusing the beams from multiple laser sources at a designated area inside the glass substrate and then irradiating it after focusing. The multiple beams are precisely focused on the same point or the same area, concentrating their energy within a very small range. By precisely controlling the focusing position, intensity, wavelength, and other parameters of the multiple laser beams, local modification can be achieved within the glass substrate to ensure that the formed modified region meets predetermined optical waveguide design requirements, such as the waveguide path, shape, and depth, thereby achieving the desired modification effect.

[0038] In this embodiment, the modified region is formed by focusing the beams of multiple laser sources, which can further improve the transmission performance of the resulting optical waveguide. Specifically, after focusing the beams of multiple laser sources on a designated area, they irradiate simultaneously or sequentially. Compared with laser modification by a single laser source, by focusing multiple beams to the same point or the same area, a higher intensity local energy field can be formed inside the glass substrate, thereby achieving a more significant change in refractive index and a deeper level of modification, thus improving the transmission efficiency of the optical waveguide and reducing transmission loss. In addition, when fabricating complex optical waveguides, a single laser source needs to irradiate point by point or line by line, which is inefficient when dealing with large areas or complex structures. Multiple laser sources can modify multiple regions simultaneously or rapidly and sequentially, significantly improving the fabrication efficiency of the optical waveguide and making it suitable for mass production and complex optical path design.

[0039] In this embodiment, the focusing depth of multiple laser light sources is adjusted to form modification regions of different depths, which continuously form a three-dimensional waveguide. Specifically, by continuously moving multiple laser light sources, their convergence point moves continuously at different depths along a preset path inside the glass substrate to form continuous modification regions of different depths, thereby constructing a three-dimensional waveguide. Furthermore, compared to single-source laser modification, multi-source laser modification more easily achieves a three-dimensional waveguide within the substrate. The beams of multiple laser light sources can converge at the same location for energy superposition. This energy superposition can provide higher energy density and more uniform energy distribution, and multiple laser light sources can simultaneously modify different locations or depths, significantly improving modification efficiency. For example, by controlling laser light sources in the Z-axis direction and the Y-axis direction to perform energy superposition of laser beams at convergence points at different locations within the substrate material, and continuously moving these two light sources so that their convergence points move continuously within the material, a three-dimensional arbitrary path, i.e., a three-dimensional waveguide, can be generated.

[0040] The technical solution provided in this embodiment of the application employs a laser modification device comprising multiple independently controllable laser beams capable of emitting beams in multiple directions to improve the transmission performance of the optical waveguide. Specifically, the high energy density field formed by multi-beam focusing enables more significant refractive index changes and deeper modification, effectively improving the transmission efficiency of the optical waveguide and reducing transmission loss. Furthermore, multiple light sources can simultaneously or rapidly modify multiple regions sequentially, significantly improving the fabrication efficiency of complex, large-area optical waveguide structures compared to the point-by-point, line-by-line irradiation method using a single light source, thus meeting the demands of large-scale production. In addition, multi-light source collaboration makes it easier to achieve three-dimensional wiring within the substrate, further improving the integration density and design flexibility of the optical waveguide and meeting the needs of diverse application scenarios.

[0041] In one embodiment, the routing shape of the optical waveguide is determined by the movement trajectory of the laser modification device relative to the glass substrate. Specifically, to form a continuous optical waveguide path, the laser beam needs to move along a preset trajectory to form an optical waveguide with a corresponding routing shape. During its movement, the laser beam forms a series of modified regions inside the glass substrate, and these regions, when connected, form the optical waveguide path. The movement of the laser beam can be achieved by moving the laser source or by moving the glass substrate. For example, when fabricating a straight waveguide, the laser beam moves along a straight line; when fabricating a curved waveguide, the laser beam moves along a curve. Laser modification technology allows for extremely high flexibility in the routing shape of optical waveguides, enabling the design of complex optical paths, such as forming three-dimensional waveguides, to meet the needs of different application scenarios.

[0042] The technical solution provided in this embodiment proposes that the path and shape of the optical waveguide are entirely determined by the trajectory of the laser beam within the glass substrate. By precisely controlling the trajectory of the laser beam, optical waveguides of arbitrary shapes can be realized, including straight, curved, and three-dimensional waveguides. This allows for the planning of complex optical paths adapted to different scenarios, achieving high-density wiring of the optical waveguide, and extending the optical path further on the glass substrate. This enables direct optical coupling between the optical waveguide structure and the optical engine, thereby achieving low-loss, high-bandwidth optical interconnect transmission. Furthermore, the high-precision characteristics of the micron-level optical path spacing achieved through laser modification further enhance the space utilization and integration of the optical waveguide structure.

[0043] Secondly, please refer to Figure 1 One embodiment of this application also provides a method for fabricating an optical waveguide based on a glass substrate, which is carried out according to the following steps: S1: Obtain a pretreated glass substrate and determine a laser modification device and a preset optical guide path based on the modification target, wherein the laser modification device includes one or more laser sources; S3: The laser modification equipment is used to perform laser modification on a designated area of ​​the glass substrate to form a modified area, wherein the refractive index of the modified area is greater than that of the unmodified substrate area in the glass substrate. S5: Move the laser modification device so that the modification area extends along the preset optical guide path to form the optical waveguide.

[0044] Specifically, in step S1 above, the glass substrate typically requires pretreatment before use to ensure the cleanliness and uniformity of its surface and interior. This pretreatment may include steps such as cleaning, polishing, and chemical treatment to remove impurities and surface defects, thereby improving the quality of the glass substrate. Further, a suitable laser modification device is selected or configured according to the modification target, and a preset optical guide path is determined.

[0045] In this embodiment, the laser source of the laser modification device is determined based on the characteristics of the glass substrate and the modification target. The modification target can be understood as the desired shape of the optical waveguide and the irradiation information, which may include the laser pulse frequency, irradiation duration, and laser power. For example, to break the chemical bonds of a certain molecule, a laser pulse within a specific wavelength range is required. Since glass is a multi-component material containing various chemical bonds, the required frequency wavelength for modification is not a fixed value. For example, since the refractive index of the modified region is related to the laser power, the refractive index of the modified region can be dynamically adjusted by adjusting the laser power to prepare optical waveguides with different transmission performance.

[0046] In this embodiment, after the optical waveguide laser direct writing is completed, the optical waveguide can be subjected to an annealing process. Since localized laser heating and rapid cooling generate mechanical stress in and around the modified region, annealing can release this stress. Furthermore, by controlling the annealing temperature and duration, the refractive index distribution of the modified region can be optimized. Optionally, the annealing process is based on a predetermined annealing temperature curve. This annealing temperature curve is a temperature change range and rate that is set as needed, with time on the x-axis and temperature on the y-axis. The annealing process is used to reconstruct the lattice structure or chemical bonds of the modified region, as an auxiliary method to adjust the refractive index of the modified region.

[0047] In one embodiment, please refer to Figure 2(a), which is a schematic diagram of the fabrication of a planar waveguide using a single light source. A single laser source 10 of the laser modification device is used to perform laser modification on a designated area of ​​the glass substrate 11 to form a planar waveguide 121 within the glass substrate. During this process, the laser beam emitted by the laser source 10 is precisely focused by a lens onto the surface or near-surface region of the glass substrate 11. By controlling the laser parameters (such as power, pulse frequency, and irradiation time), a modified region with a higher refractive index can be formed in the glass substrate 11, thereby forming the planar waveguide 121 within the glass substrate 11.

[0048] In one embodiment, please refer to Figure 2(b), which is a schematic diagram of the fabrication of a three-dimensional waveguide with a single light source. A single laser source 10 of the laser modification device is used to perform laser modification on a designated area of ​​the glass substrate 11. The laser beam is sequentially focused at different depths within the glass substrate to form a three-dimensional waveguide 122 within the glass substrate. During this process, the laser beam is sequentially focused at different depths within the glass substrate 11 by adjusting the focal length of the lens or moving the distance between the laser source 10 and the glass substrate 11. This allows for the formation of a series of modified regions at different depths within the glass substrate 11, which are continuously arranged along a predetermined optical guide path, thereby forming a three-dimensional waveguide 122 within the glass substrate 11.

[0049] In one embodiment, please refer to Figure 2(c), which is a schematic diagram of the fabrication of a planar waveguide with multiple light sources. Multiple laser sources of the laser modification device are used to perform laser modification on a designated area of ​​the glass substrate to form a planar waveguide in the glass substrate. Taking two laser sources as an example, laser source 200 and laser source 201 independently emit beams and focus them on the surface or near-surface area of ​​the glass substrate 21 through corresponding lenses. By precisely controlling the parameters and movement trajectory of each laser source, a planar waveguide 221 can be formed in the glass substrate 21.

[0050] In one embodiment, please refer to Figure 2(d), which is a schematic diagram of the fabrication of a three-dimensional waveguide with multiple light sources. Multiple laser sources of the laser modification device are used to perform laser modification on a designated area of ​​the glass substrate. The beams of the multiple laser sources are sequentially focused at different depths in the glass substrate to form a three-dimensional waveguide within the glass substrate. Taking two laser sources as an example, the beams of laser source 200 and laser source 201 are sequentially focused at different depths in the glass substrate 21 to form a series of modified regions of different depths in the glass substrate 21. These regions are continuously arranged along a preset optical guide path, thereby forming a three-dimensional waveguide 222 in the glass substrate 21.

[0051] Thirdly, one embodiment of this application also provides a co-packaged optical component, which includes a glass substrate-based optical waveguide structure as described in the first aspect above. The aforementioned co-packaged optical component is used to achieve optoelectronic integration, for example, tightly integrating an optical waveguide and a photonic integrated chip together to improve the performance and integration density of an optical communication system.

[0052] In one application scenario, a glass-substrate optical waveguide structure couples with the optical waveguide inside a photonic integrated chip via evanescent field coupling or grating coupling, transmitting information into the photonic integrated chip for processing. Evanescent field coupling utilizes the evanescent portion of the electromagnetic field generated when the optical waveguide approaches the photonic integrated chip to transmit optical signals, while grating coupling leverages the diffraction effect of a periodic structure to couple optical signals. By integrating the glass-substrate optical waveguide structure into a co-packaged optical component, efficient transmission of optical signals between the chip and external optical fibers or modules can be achieved, thereby improving the performance of the entire optical communication system.

[0053] The chip described above can be implemented by a product with a certain function. A typical implementation device is a computer. Specifically, a computer can be, for example, a personal computer, laptop computer, cellular phone, camera phone, smartphone, personal digital assistant, media player, navigation device, email device, game console, tablet computer, wearable device, or any combination of these devices.

[0054] It should be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0055] It should be noted that, in this application, unless otherwise expressly specified and limited, "between" or "in between" the first feature and the second feature can mean that the first feature and the second feature are in direct contact, or that the first feature and the second feature are in indirect contact through an intermediate medium. Furthermore, "above," "over," and "on top" of the first feature and the second feature can mean that the first feature is directly above or diagonally below the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the first feature and the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0056] It should be noted that an element is referred to as being "fixed to" or "set on" another element, which may be directly on the other element or may also include an intervening element. An element is considered to be "connected" to another element, which may be directly connected to the other element or may also include an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0057] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on its differences from other embodiments; relevant parts can be referred to in the descriptions of other embodiments. The multiple embodiments provided in this application are used to illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them.

[0058] It should be noted that the illustrations provided in the above embodiments are only schematic representations of the basic concept of this application. The illustrations only show the elements related to this application and are not drawn according to the actual number, shape and size of the elements in the actual implementation. In the actual implementation, the form, quantity and proportion of each element can be arbitrarily changed, and the layout of the elements may also be more complex.

[0059] The above description is merely an embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

[0060] Although embodiments of this application have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of this application, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. An optical waveguide structure based on a glass substrate, characterized in that, The optical waveguide structure includes a glass substrate and at least one optical waveguide, wherein the optical waveguide is located inside the glass substrate, and: The optical waveguide is determined based on a modified region in the glass substrate, which is formed by laser modification of the glass substrate using a laser modification device. The refractive index of the modified region is greater than that of the unmodified substrate region in the glass substrate.

2. The optical waveguide structure according to claim 1, characterized in that, The optical waveguide is a three-dimensional waveguide; the three-dimensional waveguide includes modified regions located at different depths inside the glass substrate.

3. The optical waveguide structure according to claim 1, characterized in that, The laser modification equipment includes a single laser source; the modification area is formed by irradiating a designated area inside the glass substrate with the beam of the single laser source.

4. The optical waveguide structure according to claim 3, characterized in that, The laser modification device also includes a lens; the lens is used to adjust the focusing depth of the laser beam to form modification regions of different depths, wherein the modification regions of different depths are used to form a three-dimensional waveguide.

5. The optical waveguide structure according to claim 1, characterized in that, The laser modification equipment includes multiple laser light sources; the modification area is formed by focusing the beams of the multiple laser light sources at a designated area inside the glass substrate and then irradiating it after focusing.

6. The optical waveguide structure according to claim 5, characterized in that, The focusing depth of the beams of the multiple laser sources is adjusted to form modified regions of different depths, wherein the modified regions of different depths are used to form a three-dimensional waveguide.

7. The optical waveguide structure according to claim 1, characterized in that, The routing shape of the optical waveguide is determined by the movement trajectory of the laser modification device relative to the glass substrate.

8. A method for fabricating an optical waveguide based on a glass substrate, characterized in that, The method includes: A pretreated glass substrate is obtained, and a laser modification device and a preset optical guide path are determined based on the modification target, wherein the laser modification device includes one or more laser sources; The laser modification equipment is used to perform laser modification on a designated area of ​​the glass substrate to form a modified area, wherein the refractive index of the modified area is greater than that of the unmodified substrate area in the glass substrate. The laser modification device is moved so that the modification area extends along the preset optical guide path to form the optical waveguide.

9. The method for fabricating an optical waveguide according to claim 8, characterized in that, Laser modification of a designated area of ​​the glass substrate using the laser modification equipment includes: Using a single laser source, the beam of the laser source is sequentially focused at different depths inside the glass substrate to form a three-dimensional waveguide; or, Multiple laser light sources are used, and the beams of the multiple laser light sources are sequentially focused at different depths of the glass substrate to form a three-dimensional waveguide.

10. The method for fabricating an optical waveguide according to claim 8, characterized in that, The method further includes: The optical waveguide is subjected to an annealing process, wherein the annealing process is based on a predetermined annealing temperature profile.

11. A co-packaged optical component, characterized in that, The co-packaged optical component includes a glass substrate-based optical waveguide structure as described in any one of claims 1 to 7.

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