Optical coupling structure and preparation method thereof, and optical component

Abstract

The present disclosure relates to an optical coupling structure, a preparation method thereof, and an optical component. The optical coupling structure includes a stacked optical guide layer and an optical collimating layer. The optical guide layer includes: a first base layer, and a guide protrusion provided on the surface of the first base layer facing away from the optical collimating layer. The guide protrusion has an optical coupling surface and a total reflection surface; wherein the optical coupling surface is perpendicular to the surface of the first base layer facing away from the optical collimating layer, and the total reflection surface is opposite to the optical coupling surface and is arranged at an angle to the first base layer. The optical coupling structure can solve the problem of difficult coupling and packaging between edge-emitting optical devices and planar optical devices, thereby facilitating efficient coupling between edge-emitting optical devices and planar optical devices in large-scale optoelectronic hybrid integration.

Description

Technical Field

[0001] The present disclosure relates to the field of integrated optical technology, and in particular to an optical coupling structure and a preparation method thereof, and an optical component. Background Art

[0002] With the rapid development of science and technology, optical communication technology based on integrated optical devices is moving towards ultra-high speed, ultra-large bandwidth, ultra-low power consumption, ultra-compactness, and ultra-reliability. This has made the use of co-packaged optics (CPO) technology to achieve large-scale optoelectronic hybrid integration a future development direction for optical communication technology.

[0003] Optoelectronic co-packaging technology involves packaging optical waveguide chips and circuit chips together on a single substrate, including three-dimensional stacking of these chips. However, achieving efficient coupling between the silicon-based optical waveguides in the waveguide chips and external light sources, or between the silicon-based optical waveguides and optical fibers, has been a pressing challenge in applying optoelectronic co-packaging technology to large-scale optoelectronic hybrid integration. Summary of the Invention

[0004] Based on this, the embodiments of the present disclosure provide an optical coupling structure and its preparation method, as well as an optical component, which can solve the problem of difficult coupling packaging between edge-emitting optical devices and planar optical devices, thereby facilitating the realization of efficient coupling between edge-emitting optical devices and planar optical devices in large-scale optoelectronic hybrid integration.

[0005] To achieve the above objectives, in one aspect, some embodiments of the present disclosure provide a light coupling structure comprising a light guiding layer and a light collimating layer that are stacked.

[0006] The light guiding layer comprises a first base layer and a guiding protrusion disposed on a surface of the first base layer facing away from the light collimating layer. The guiding protrusion has a light coupling surface and a total reflection surface. The light coupling surface is perpendicular to the surface of the first base layer facing away from the light collimating layer, and the total reflection surface is opposite the light coupling surface and disposed at an angle relative to the first base layer. The total reflection surface is configured to: totally reflect light signals coupled into the light coupling surface back to the light collimating layer, thereby collimating or converging the light signals; or totally reflect light signals collimated or converging by the light collimating layer back to the light coupling surface, thereby coupling them out through the light coupling surface.

[0007] In the disclosed embodiment, the stacking arrangement of the light-guiding layer and the light-collimating layer of the optical coupling structure not only facilitates large-scale production, but also facilitates mounting the optical coupling structure as a whole on a planar optical device (e.g., a silicon-based optical waveguide) or stacking the optical coupling structure. Furthermore, the optical coupling surface in the optical guiding layer is perpendicular to the first base layer, so that the corner area formed between the optical coupling surface and the first base layer can have space to accommodate optical devices that emit light from the edge (e.g., a laser, an optical fiber), thereby facilitating direct coupling of the end face on the edge side of the optical device with the optical coupling surface. Thus, by utilizing the above-mentioned optical coupling structure or its stacking, it is easy to realize mutual coupling between different optical devices in large-scale optoelectronic hybrid integration.

[0008] On this basis, after coupling the optical coupling structure between the planar optical device and the edge-emitting optical device, the optical coupling structure is used to guide, collimate, or converge the optical path of the optical signal. For example, the total reflection surface fully reflects the optical signal, and the optical collimation layer collimates or converges the optical signal. This can effectively balance the mode field difference of the optical signal between the edge-emitting optical device and the planar optical device. For example, the output light of the edge-emitting optical device is converted to a surface-perpendicular output, that is, the small mode field beam is expanded and converted into a large mode field beam. This can reduce the positional alignment accuracy when coupling the planar optical device and the edge-emitting optical device, thereby reducing coupling loss and improving the optical coupling efficiency between the planar optical device and the edge-emitting optical device.

[0009] In addition, the photonic chip or photonic chip integration obtained by coupling using the above-mentioned optical coupling structure is also convenient for chip testing at the wafer level, thereby improving production efficiency in large-scale photonic chip production and reasonably reducing production costs.

[0010] In some embodiments, the light collimating layer includes a second substrate and a microlens or an array thereof. The second substrate is located on a surface of the first substrate facing away from the guide bumps. The microlens or the array thereof is disposed on the second substrate. For example, the surface of the second substrate facing away from the first substrate is provided with a groove, and the microlens or the array thereof is disposed within the groove. This ensures that the surface of the second substrate facing away from the first substrate is flat, facilitating mounting of the light collimating layer on a planar optical device.

[0011] In some embodiments, the light collimation direction of the microlens or its array is perpendicular to the surface of the second substrate facing away from the first substrate. Thus, when the light collimating layer couples out an optical signal, the light collimating layer's output angle can be perpendicular to the surface of the second substrate, meaning that the light collimating layer can emit a large mode field beam perpendicular to the surface. Based on this, the orthographic projection of the microlens or its array on the second substrate at least partially overlaps with the orthographic projection of the total reflection surface on the second substrate, ensuring that the light signal fully reflected by the total reflection surface can be coupled to the microlens or its array.

[0012] In some embodiments, the optical coupling structure further includes a metal pad. The first and second substrates are connected via the metal pad. The orthographic projection of the metal pad on the second substrate is located outside the orthographic projection of the microlens or its array on the second substrate. In this manner, the metal pad can effectively secure the light guiding layer and the light collimating layer while not adversely affecting the transmission of optical signals between the light guiding layer and the light collimating layer.

[0013] In other embodiments, the first base layer and the second base layer are bonded together by optical adhesive, which can simplify the bonding process between the light guiding layer and the light collimating layer.

[0014] In some embodiments, the optical coupling structure further comprises: a mechanical positioning structure disposed on a surface of the second substrate facing away from the first substrate, and configured to be connected to an external optical device.

[0015] Optionally, the mechanical positioning structure includes at least one of a slot, a block, a positioning boss, a positioning hole or a positioning groove.

[0016] In the embodiment of the present disclosure, a mechanical positioning structure is provided on the surface of the light collimating layer facing away from the light guiding layer. The mechanical positioning structure can be used to achieve a mechanical connection between the optical coupling structure and the optical device, such as a pluggable connection, thereby simplifying the mounting of the optical coupling structure and the optical device and achieving passive installation of the optical coupling structure and the optical device.

[0017] In some embodiments, the light coupling structure further comprises an optical device mounting portion. The optical device mounting portion is disposed on a surface of the first substrate facing away from the second substrate, and is located on a side of the light coupling surface facing away from the total reflection surface. The optical device mounting portion is configured to mount an optical device. This allows an edge-emitting optical device to be mounted on the light guiding layer using the optical device mounting portion, facilitating direct coupling of the light emitting surface of the optical device with the light coupling surface of the light guiding layer.

[0018] Optionally, the optical device mounting portion includes: an optical device supporting platform or an optical device receiving groove.

[0019] In some embodiments, the optical coupling structure further includes an optical device packaging cover. The optical device packaging cover is disposed on a side of the optical device mounting portion facing away from the first substrate and is configured to encapsulate the optical device mounted on the optical device mounting portion. In this manner, the optical device packaging cover can provide packaging and protection for the optical device, for example, to prevent dust and moisture.

[0020] In some embodiments, the optical device mounting portion is configured to mount an active optical device. The optical device mounting portion further includes an electrode guide region. This electrode guide region comprises interconnected inner and outer electrodes, with the orthographic projections of the inner and outer electrodes on the first substrate respectively located on the inner and outer sides of the orthographic projection boundary of the optical device package cover on the first substrate. The inner electrode is configured to directly connect to the active optical device, and the outer electrode is configured to directly connect to an external power source. This simplifies the connection between the active optical device and the external power source using the electrode guide region.

[0021] In some embodiments, the first base layer and / or the second base layer is a silicon-based layer.

[0022] Optionally, the first base layer and the guide protrusion are an integrated structure.

[0023] Optionally, the microlens or its array is an integrated structure with the second base layer.

[0024] Optionally, the first base layer and the guide bumps are an integral structure, and the microlens or its array is an integral structure with the second base layer.

[0025] In this way, it is convenient to prepare a light guiding layer or a light collimating layer using a silicon wafer in a patterned manner, so as to improve production efficiency in large-scale production.

[0026] In some embodiments, the light guiding layer further comprises a metal reflective film disposed on the total reflection surface. The reflectivity of the metal reflective film is greater than the reflectivity of the total reflection surface. This effectively improves the total reflection efficiency of the total reflection surface, thereby improving the light coupling efficiency of the light coupling structure.

[0027] In some embodiments, the light coupling structure further includes an antireflection coating. The antireflection coating is disposed on the surface of the light coupling surface facing away from the total reflection surface, and / or on the surface of the microlens or its array facing away from the total reflection surface. This reduces or eliminates light reflected from the corresponding surfaces, thereby increasing light transmission through the light coupling structure and thereby improving the light coupling efficiency of the light coupling structure.

[0028] In some embodiments, the optical coupling structure further comprises: a transfer collimating layer and a transfer guiding layer stacked on a surface of the optical collimating layer facing away from the optical guiding layer. The transfer collimating layer has the same structure as the optical collimating layer, and is configured to collimate or converge the optical signal transmitted by the optical collimating layer into the transfer guiding layer, or collimate or converge the optical signal transmitted by the transfer guiding layer into the optical collimating layer. The transfer guiding layer has the same structure as the optical guiding layer, and is configured to direct the optical signal transmitted by the transfer collimating layer to the output, or to direct the external optical signal to the transfer collimating layer.

[0029] On the other hand, some embodiments of the present disclosure provide a method for preparing an optical coupling structure, which is used to prepare the optical coupling structure in some of the above embodiments. The preparation method includes the following steps.

[0030] The wafer is processed to form a light guiding layer. A plurality of guiding bumps are formed on the front side of the light guiding layer. The guiding bumps include a light coupling surface perpendicular to the surface of the first wafer and a total reflection surface opposite the light coupling surface and arranged at an angle to the surface of the first wafer.

[0031] The wafer is processed to form a light-collimating layer. A plurality of microlenses are formed on the front side of the light-collimating layer.

[0032] The back side of the light guiding layer and the back side of the light collimating layer are bonded so that one guiding bump corresponds to at least one microlens.

[0033] A light coupling structure is obtained. The light coupling structure includes: a guide bump and at least one micro lens corresponding to the guide bump.

[0034] The method for preparing an optical coupling structure provided by the embodiments of the present disclosure can use a wafer to independently prepare guide bumps to form a light guiding layer in the optical coupling structure; and use a wafer to independently prepare microlenses to form a light collimating layer in the optical coupling structure. That is, the light guiding layer and the light collimating layer are prepared separately. Therefore, according to the different applications of the optical coupling structure, a wafer with suitable microlenses can be selected and bonded to a wafer with guide bumps. In this way, the versatility of the light guiding layer can be improved, which is conducive to reducing the production cost of the optical coupling structure in large-scale production.

[0035] In addition, the method for preparing the optical coupling structure provided in the embodiments of the present disclosure is used to prepare the optical coupling structures in some of the aforementioned embodiments. The technical effects achieved by the aforementioned optical coupling structures can also be achieved by this method, and will not be described in detail here.

[0036] In some embodiments, the optical coupling surface of the guide bump is formed using a dry etching process, and the total reflection surface is formed using a wet etching process. Dry etching has a high etching rate and causes minimal lateral erosion of the edges. Therefore, using dry etching to prepare the optical coupling surface of the guide bump is not only easy to implement, but also ensures the perpendicularity between the optical coupling surface and the surface of the first wafer. Wet etching has high etching accuracy. Therefore, using wet etching to prepare the total reflection surface can ensure that the angle between the total reflection surface and the surface of the first wafer meets the requirements, that is, ensure the molding accuracy of the total reflection surface.

[0037] In some embodiments, before bonding the back side of the first wafer and the back side of the second wafer, the method for preparing the optical coupling structure further includes: forming a metal reflective film on the total reflection surface of the guide bump.

[0038] In yet another aspect, some embodiments of the present disclosure provide an optical assembly. The optical assembly includes: at least one light emitter, at least one optical fiber, and the optical coupling structure described in any of the above embodiments. The optical fibers correspond one-to-one with the light emitters. The optical input end of the optical fiber is coupled to the corresponding light emitter, and the optical output end of the optical fiber is coupled to the optical coupling surface of the light guide layer.

[0039] In large-scale device integration using co-sealed optical technology, the optical components provided by the embodiments of the present disclosure can be coupled to the photonic chip integration through an optical coupling structure after a high-temperature process, thereby avoiding adverse effects of the high-temperature process on the optical components.

[0040] In some embodiments, the diameter of the optical fiber's light-emitting end is smaller than the diameter of its light-input end, facilitating the long-distance fanning of multiple optical fibers. Thus, in applications of co-sealed optical technology, the fanning of individual optical fibers can achieve long-distance coupling between the optical coupling structure and the optical transmitter. This also allows for large-scale device integration by placing the optical transmitter in an area away from the core chipset, facilitating management of transmitter aging, reassembly, and heat dissipation.

[0041] In some embodiments, the optical assembly further includes an adapter interface disposed at the distal end of the optical fiber of the optical transmitter. Thus, the adapter interface facilitates a pluggable connection between the optical transmitter and an external device, thereby simplifying the assembly process between the optical assembly and the external device.

[0042] In some embodiments, the light coupling structure includes a transition collimating layer and a transition guiding layer, and the optical assembly further includes an optical waveguide or a photonic chip coupled to the transition guiding layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0044] Figure 1 is a cross-sectional schematic diagram of an optical coupling structure provided in one embodiment;

[0045] Figure 2 for Figure 1 A schematic diagram of an optical path of the optical coupling structure shown;

[0046] Figure 3 for Figure 1 Another optical path schematic diagram of the optical coupling structure shown;

[0047] Figure 4is a schematic diagram of a stacking of an optical coupling structure provided in one embodiment;

[0048] Figure 5 is a cross-sectional schematic diagram of another optical coupling structure provided in an embodiment;

[0049] Figure 6 is a cross-sectional schematic diagram of another optical coupling structure provided in an embodiment;

[0050] Figure 7 is a cross-sectional schematic diagram of another optical coupling structure provided in an embodiment;

[0051] Figure 8 is a cross-sectional schematic diagram of another optical coupling structure provided in an embodiment;

[0052] Figure 9 is a cross-sectional schematic diagram of another optical coupling structure provided in an embodiment;

[0053] Figure 10 is a structural schematic diagram of an optical coupling structure provided in one embodiment;

[0054] Figure 11 is a schematic structural diagram of another optical coupling structure provided in an embodiment;

[0055] Figure 12 1 is a schematic flow chart of a method for preparing an optical coupling structure provided in one embodiment;

[0056] Figure 13 A diagram showing steps for preparing an antireflection film provided in one embodiment;

[0057] Figure 14 A diagram showing steps for preparing another antireflection film provided in one embodiment;

[0058] Figure 15 A diagram showing steps for preparing a metal reflective film provided in one embodiment;

[0059] Figure 16 A diagram of the steps for preparing a metal pad provided in one embodiment;

[0060] Figure 17 A diagram showing the steps for preparing a mechanical positioning structure provided in one embodiment;

[0061] Figure 18 A diagram showing steps for preparing an optical device mounting portion provided in one embodiment;

[0062] Figure 19 A diagram showing steps for preparing another optical device mounting portion provided in one embodiment;

[0063] Figure 20 is a schematic structural diagram of an optical component provided in one embodiment;

[0064] Figure 21 for Figure 20 An enlarged schematic diagram of coupling an optical coupling structure with an optical fiber in an optical component is shown;

[0065] Figure 22 Schematic diagram of the structure of another optical component provided in one embodiment.

[0066] Description of reference numerals:

[0067] 100-optical coupling structure, 100-1-first optical coupling structure, 100-2-second optical coupling structure, 100-3-third optical coupling structure, 100-4-fourth optical coupling structure, 10-light guiding layer, 20-light collimating layer, 101-first base layer, 102-guide bump, 103-metal reflective film, S CL - Optical coupling surface, S TR -total reflection surface, 201-second base layer, 202-micro lens, 203-groove, S A -The surface of the second substrate facing away from the first substrate, 1-first optical device, 2-second optical device, 1-1-optical waveguide, 1-2-laser, 1-3-optical fiber, 30-antireflection film, 40-metal pad, 50-mechanical positioning structure, 60-optical device mounting portion, 610-electrode guide area, 611-inner electrode, 621-outer electrode, 70-optical device packaging cover, 71-sealing layer, 1001-first wafer, 1002-second wafer, 400-patterned metal pad, 1000-optical component, 3-light emitter, 4-adapter interface. DETAILED DESCRIPTION

[0068] To facilitate understanding of the present disclosure, a more comprehensive description of the present disclosure will be provided below with reference to the accompanying drawings. The drawings illustrate embodiments of the present disclosure. However, the present disclosure can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the present disclosure.

[0069] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art in the art of the present disclosure. The terms used herein in the specification of the present disclosure are only for the purpose of describing specific embodiments and are not intended to limit the present disclosure.

[0070] It should be understood that when an element or layer is referred to as being “on,” “adjacent,” “connected to,” or “coupled to” another element or layer, it can be directly on, adjacent, connected, or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly adjacent to,” “directly connected to,” or “directly coupled to” another element or layer, there are no intervening elements or layers present.

[0071] It should be understood that although the terms first, second, third, etc. may be used to describe various elements, components, regions, layers, and / or parts, these elements, components, regions, layers, and / or parts should not be limited by these terms. These terms are merely used to distinguish one element, component, region, layer, or part from another element, component, region, layer, or part. Therefore, without departing from the teachings of the present disclosure, the first element, component, region, layer, or part discussed below may be represented as a second element, component, region, layer, or part.

[0072] Spatially relative terms such as "under," "beneath," "beneath," "under," "above," "above," etc., may be used herein to describe the relationship of an element or feature shown in the figures to other elements or features. It should be understood that in addition to the orientations shown in the figures, spatially relative terms also include different orientations of the device in use and operation. For example, if the device in the drawings is turned over, the element or feature described as "under" or "beneath" or "beneath" the other elements will be oriented as "above" the other elements or features. Thus, the exemplary terms "under" and "under" can include both upper and lower orientations. In addition, the device can also include alternative orientations (e.g., rotated 90 degrees or other orientations), and the spatial descriptors used herein are interpreted accordingly.

[0073] As used herein, the singular forms "a," "an," and "the" may also include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "include," "comprising," "having," and the like specify the presence of stated features, integers, steps, operations, components, parts, or combinations thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, components, parts, or combinations thereof. Also, in this specification, the term "and / or" includes any and all combinations of the relevant listed items.

[0074] Embodiments of the invention are described herein with reference to cross-sectional views which are schematic representations of ideal embodiments (and intermediate structures) of the present disclosure, such that variations in the shapes shown due to, for example, manufacturing techniques and / or tolerances are anticipated. Accordingly, embodiments of the present disclosure should not be limited to the specific shapes of the zones shown herein, but include deviations in shapes due to, for example, manufacturing techniques. For example, A and B are perpendicular, and the angle between A and B can be 90°, or the angle between A and B can be an angle within a permissible deviation range above and below 90°. Accordingly, the zones shown in the figures are schematic in nature, and their shapes do not represent the actual shapes of the zones of the device, and do not limit the scope of the invention.

[0075] In the field of optical communications, silicon-based optical waveguides in optical waveguide chips need to be coupled with optical fibers or external light sources to receive and transmit optical signals. Currently, coupling technologies for silicon-based optical waveguides mainly fall into two categories: edge coupling technology based on pattern spot converters, and surface vertical coupling technology based on grating couplers.

[0076] In some examples, edge coupling technology is used to couple silicon-based optical waveguides and optical fibers. For example, the end face of the edge side of the silicon-based optical waveguide is directly connected to the end face of the optical fiber; or a microlens is set between the silicon-based optical waveguide and the optical fiber to use the microlens for free-space optical coupling. This can reduce the coupling loss between the silicon-based optical waveguide and the optical fiber, thereby achieving efficient coupling between the two. However, the test of the optical waveguide chip obtained by coupling in the above manner cannot be achieved at the wafer level. It needs to be performed on a single chip obtained by deep etching or grinding and polishing after chip cutting, which is not conducive to large-scale production of chips at low cost.

[0077] In other examples, surface vertical coupling technology is used to couple silicon-based optical waveguides and optical fibers. For example, grating devices are formed on the surface of a silicon-based optical waveguide. This facilitates chip testing and packaging at the wafer level. However, grating devices have limited optical bandwidth and are sensitive to the polarization state of light. Furthermore, the central wavelength of grating devices is difficult to precisely control due to variations in processing accuracy and ambient temperature. Therefore, improving the coupling efficiency of grating devices places higher demands on their manufacturing process and optimized design.

[0078] In summary, compared with the edge coupling technology, the coupling performance obtained by coupling the silicon-based optical waveguide and optical fiber using the surface vertical coupling technology is slightly worse.

[0079] Based on this, see Figure 1 Some embodiments of the present disclosure provide a light coupling structure 100. The light coupling structure 100 includes a light guiding layer 10 and a light collimating layer 20 that are stacked.

[0080] In some examples, such as Figure 1 As shown, the light guiding layer 10 comprises: a first base layer 101, and a guiding protrusion 102 provided on the surface of the first base layer 101 away from the light collimating layer 20. The guiding protrusion 102 has a light coupling surface S CL and the total reflection surface S TR ; Among them, the optical coupling surface S CL The total reflection surface S is perpendicular to the surface of the first base layer 101 facing away from the light collimating layer 20. TR With the optical coupling surface S CL It is disposed opposite to and at an angle α to the first base layer 101 .

[0081] The light guide layer 10 is used to guide the transmission of optical signals. The first base layer 101 serves as the base of the light guide layer 10 and is formed of a light-transmitting material. For example, the first base layer 101 is a silicon base layer. The guide bumps 102 can be integrated with the first base layer 101, thereby facilitating the preparation of the light guide layer 10 using a silicon wafer in a graphical manner. In addition, the embodiment of the present disclosure does not limit the shape of the guide bumps 102, as long as it has the aforementioned light coupling surface S CL and the total reflection surface S TR Limited.

[0082] Optical coupling surface S CL The optical coupling surface SCL is perpendicular to the first substrate 101, so that the corner area formed between the optical coupling surface SCL and the first substrate 101 can accommodate the first optical device. The first optical device can be an edge-emitting optical device, such as a laser, an optical fiber, etc. CL By coupling with the first optical device, the optical signal transmitted by the first optical device can be coupled into the light guiding layer 10 , or the optical signal in the light guiding layer 10 can be coupled out to the first optical device.

[0083] Total reflection surface S TR As the total reflection interface of the light guide layer 10, the total reflection surface S TR The angle α between the first base layer 101 and the guide protrusion 102 is related to the material of the first base layer 101, so as to ensure that the light incident on the total reflection surface S TR For example, the guide bump 102 and the first base layer 101 are made of silicon, and the total reflection surface S TR The angle α between the substrate and the first base layer 101 is greater than the critical angle of total reflection of silicon material, for example, α>42°, or α=45°.

[0084] In some examples, such as Figure 1As shown, the light collimating layer 20 includes: a second substrate 201, and a microlens 202 or an array thereof disposed in a groove 203 of the second substrate 201. The second substrate 201 is located on the surface of the first substrate 101 away from the guide protrusion 102. The groove 203 is disposed on the surface S of the second substrate 201 away from the first substrate 101. A The micro lens 202 is disposed in the groove 203 of the second base layer 201, which ensures that the surface S of the second base layer 201 facing away from the first base layer 101 is A The surface of the optical collimating layer 20 is flat, thereby facilitating the mounting of the optical collimating layer 20 and a planar optical device.

[0085] Furthermore, in some other examples, it is also permissible to directly dispose the microlens 202 or its array on the surface of the second substrate 201 facing away from the guide bumps 102 .

[0086] The light collimating layer 20 is used to collimate or focus optical signals. The second base layer 201, serving as the substrate for the light collimating layer 20, is formed of a light-transmitting material. For example, the second base layer 201 is a silicon base layer. The microlenses 202 or their array can be integrally formed with the second base layer 202. This facilitates the fabrication of the light collimating layer 20 using a silicon wafer through patterning. Furthermore, the number, shape, size, and characteristic parameters of the microlenses 202 disposed within the grooves of the second base layer 201 can be selected based on actual needs and are not limited in this disclosure.

[0087] On this basis, see Figure 2 and Figure 3 , the light coupling surface S of the light coupling structure 100 CL It can be coupled to the first optical device 1. Optionally, the first optical device 1 is a laser, optical fiber, or other edge-emitting optical device. The surface of the light collimating layer 20 facing away from the light guiding layer 10 can be coupled to the second optical device 2. Optionally, the second optical device 2 is a planar optical device such as a silicon-based optical waveguide or photonic chip. In this way, the transmission of optical signals between the first optical device 1 and the second optical device 2 can be achieved through the optical coupling structure 100. Furthermore, the optical path of the optical signal in the optical coupling structure 100 varies depending on the position of the incident light source.

[0088] For example, the first optical device 1 is an incident light source. Figure 2 As shown, the optical coupling surface S CL is configured to couple the optical signal transmitted by the first optical device 1 into the total reflection surface S TR Total reflection surface S TR is configured so that the light coupling surface S CL The coupled optical signal is totally reflected to the light collimating layer 20, such as the micro lens 202. The light collimating layer 20 is configured to reflect the total reflection surface S TRThe reflected optical signal is collimated and then coupled out, for example, to the second optical device 2 .

[0089] For example, the second optical device 2 is an incident light source. Figure 3 As shown, the light collimating layer 20 is configured to couple the optical signal transmitted by the second optical device 2 into the total reflection surface S TR Total reflection surface S TR It is configured to make the light signal coupled into the light collimating layer 20 totally reflected to the light coupling surface S CL . Optical coupling surface S CL is configured to make the total reflection surface S TR The reflected optical signal is coupled out, for example, to the first optical device 1 .

[0090] It should be added that after coupling the optical coupling structure 100 with the corresponding optical device, multiple optical coupling structures 100 can be stacked in different ways according to different requirements of optical signal transmission to achieve mutual coupling between multiple different optical devices.

[0091] For examples, see Figure 4 The optical waveguide 1-1 is a planar optical waveguide, and its light-incoming side edge and light-outgoing side edge both adopt a step structure. At the light-incoming side edge of the optical waveguide 1-1, its light-incoming surface is aligned with the light coupling surface S of the first light coupling structure 100-1. CL Coupling. Connect the laser 1-2 to the optical coupling surface S of the second optical coupling structure 100-2. CL Then, on the light collimating layer 20 of the first light coupling structure 100-1, a second light coupling structure 100-2 is stacked in a buckled manner, so that the coupling between the laser 1-2 and the optical waveguide 1-1 can be achieved. The optical path of the corresponding optical signal is as follows: Figure 4 As shown in .

[0092] Similarly, at the light-emitting side edge of the optical waveguide 1-1, its light-emitting surface is aligned with the light coupling surface S of the third light coupling structure 100-3. CL Coupling. Connect the optical fiber 1-3 to the optical coupling surface S of the fourth optical coupling structure 100-4. CL Then, a fourth optical coupling structure 100-4 is stacked on the light collimating layer 20 of the third optical coupling structure 100-3, but it is necessary to ensure that the micro lenses 202 of the two are facing each other, that is, the output light of the micro lenses 202 in the third optical coupling structure 100-3 can be converged by the micro lenses 202 in the fourth optical coupling structure 100-4. In this way, the optical waveguide 1-1 can be coupled to the optical fiber 1-3 through the two stacked optical coupling structures 100, and its optical path is as follows: Figure 4 As shown in .

[0093] It can be seen that after the light coupling structure 100 is coupled to the corresponding optical device, the coupling between any two optical devices can be presented as surface vertical coupling.

[0094] On this basis, it can be understood that the optical coupling structure 100 can also be composed of at least two optical coupling structures 100 stacked in the aforementioned embodiments. For example, the optical coupling structure 100 also includes: a transfer collimation layer and a transfer guide layer stacked on the surface of the optical collimation layer 20 facing away from the optical guide layer 10; wherein, the structure of the transfer collimation layer is the same as that of the optical collimation layer 20, and the structure of the transfer guide layer is the same as that of the optical guide layer 10. This embodiment of the present disclosure will not be described in detail. The transfer collimation layer is configured to: collimate or converge the optical signal transmitted by the optical collimation layer 20 into the transfer guide layer, or collimate or converge the optical signal transmitted by the transfer guide layer into the optical collimation layer 20. The transfer guide layer is configured to: guide the optical signal transmitted by the transfer collimation layer to the output, or guide the external optical signal to be transmitted into the transfer collimation layer.

[0095] In summary, in the embodiment of the present disclosure, the light-guiding layer 10 and the light-collimating layer 20 of the light-coupling structure 100 are stacked, which is not only convenient for large-scale production, but also convenient for mounting the light-coupling structure 100 on a planar optical device (such as a silicon-based optical waveguide) or stacking the light-coupling structure 100. CL is perpendicular to the first base layer 101 so that the light coupling surface S CL The corner area formed between the first substrate 101 can have space to accommodate optical devices (such as lasers, optical fibers) with edge light, so as to facilitate the connection between the end face of the edge side of the optical device and the light coupling surface S CL Direct coupling. Thus, by using the above optical coupling structure 100 or its stack, it is easy to realize coupling packaging between optical devices in large-scale optoelectronic hybrid integration.

[0096] On this basis, after coupling the optical coupling structure 100 between the planar optical device and the edge-emitting optical device, the optical coupling structure 100 is used to guide, collimate or converge the optical path of the optical signal, such as the total reflection surface S TR The total reflection of the optical signal, along with the collimation or convergence of the optical signal by the microlenses 202 or their array, can effectively balance the mode field differences between edge-emitting optical devices and planar optical devices. For example, the light emitted from the edge-emitting optical device can be converted to be emitted perpendicular to the surface, thereby expanding a small mode field beam into a large mode field beam. This can reduce the positional accuracy of the coupling between the planar optical device and the edge-emitting optical device, thereby reducing coupling losses and improving the optical coupling efficiency between the planar optical device and the edge-emitting optical device.

[0097] In addition, for the photonic chip obtained by coupling using the above-mentioned optical coupling structure 100, it is also convenient to perform chip testing at the wafer level, thereby improving production efficiency in large-scale photonic chip production and reasonably reducing production costs.

[0098] It should be noted that the light collimating layer 20 is used to collimate or converge light signals. The emission angle of the light collimating layer 20 can be achieved by properly designing the microlens 202, for example, by properly designing the position of the microlens 202 in the second base layer 201, the characteristic parameters of the microlens 202, etc.

[0099] For some examples, see Figure 1 The light collimation direction of the microlens 202 or its array is the same as the surface S of the second substrate 201 away from the first substrate 101. A Thus, in the process of coupling the optical signal from the light collimating layer 20 to the second optical device 2, the emission angle of the light collimating layer 20 can be perpendicular to the surface S of the second optical device 2. A , that is, the light collimating layer 20 can emit a large mode field beam perpendicular to the surface. Based on this, the orthographic projection of the microlens 202 or its array on the second substrate 201 is perpendicular to the total reflection surface S TR The orthographic projections on the second base layer 201 at least partially overlap, which can ensure that the total reflection surface S TR The totally reflected optical signal can be coupled to the microlens 202 or its array.

[0100] As described above, by utilizing the optical coupling structure 100, a 90° or approximately 90° bend of the optical signal can be achieved during the transmission of the optical signal, so as to effectively convert the edge emission of the optical signal into a surface vertical emission, that is, the small mode field beam emission can be converted into a large mode field beam emission, thereby effectively balancing the mode field difference of the optical signal between the planar optical device and the edge-emitting optical device.

[0101] For some examples, see Figure 5 The optical coupling structure 100 further includes an anti-reflection film 30. The anti-reflection film 30 can be disposed on the optical coupling surface S CL The back-total reflection surface S TR and / or, disposed on the microlens 202 away from the total reflection surface S TR In this way, the reflected light of the corresponding surface can be reduced or eliminated to increase the light transmittance of the light coupling structure 100, thereby improving the light coupling efficiency of the light coupling structure 100. Optionally, the antireflection film 30 is a silicon nitride film or a porous silicon dioxide film.

[0102] For some examples, see Figure 6 , the light guide layer 10 further includes; provided on the total reflection surface S TR The metal reflective film 103 on the total reflection surface S has a reflectivity greater than that of the total reflection surface S.TR The reflectivity of the total reflection surface S TR The total reflection efficiency is improved, thereby improving the light coupling efficiency of the light coupling structure 100. In addition, the material of the metal reflective film 103 can be selected and set according to actual needs, and the embodiment of the present disclosure does not limit this. For example, the metal reflective film 103 is a gold plating layer.

[0103] For some examples, see Figure 6 , the optical coupling structure 100 also includes: a metal pad 40. The first base layer 101 and the second base layer 201 are connected via the metal pad 40. The material of the metal pad 40 can be selected and set according to actual needs, such as copper, tin and other solders. The present disclosed embodiment is not limited to this. The orthographic projection of the metal pad 40 on the second base layer 201 is located outside the orthographic projection of the microlens 202 or its array on the second base layer 201, that is, the setting position of the metal pad 40 needs to avoid the passage area of ​​the light signal. In this way, while the metal pad 40 is used to effectively fix the light guiding layer 10 and the light collimating layer 20, the metal pad 40 does not affect the transmission of the light signal between the light guiding layer 10 and the light collimating layer 20.

[0104] Furthermore, the connection method between the light guiding layer 10 and the light collimating layer 20 is not limited to this. For example, the light guiding layer 10 and the light collimating layer 20 may be bonded together using optical adhesive, thereby simplifying the bonding process between the light guiding layer 10 and the light collimating layer 20. Alternatively, for example, mechanical connection portions, such as latches or slots, may be formed on the surface of the first base layer 101 facing away from the guide protrusions 102 and the surface of the second base layer 201 closer to the first base layer 101, thereby achieving a mechanical connection between the light guiding layer 10 and the light collimating layer 20.

[0105] It is worth mentioning that in some embodiments, see Figure 7 The optical coupling structure 100 further includes a mechanical positioning structure 50. The mechanical positioning structure 50 is disposed on a surface S of the second base layer 201 that is away from the first base layer 101. A , configured as an external optical device, such as a second optical device 2.

[0106] Optionally, the mechanical positioning structure 50 includes at least one of a slot, a block, a positioning boss, a positioning hole, or a positioning groove, but is not limited thereto, and any other mechanical structure that can be used to achieve the connection between the optical coupling structure and the second optical device is acceptable.

[0107] In the embodiment of the present disclosure, the surface S of the light collimating layer 20 facing away from the light guiding layer 10 AThe mechanical positioning structure 50 can be used to achieve a mechanical connection between the optical coupling structure 100 and the optical device, such as a pluggable connection. This simplifies the mounting of the optical coupling structure 100 and the optical device, enabling passive assembly between the optical coupling structure 100 and the optical device. This eliminates the need for alignment using a light source, allowing assembly of the optical coupling structure 100 and the optical device. Furthermore, the use of the mechanical positioning structure 50 for mounting ensures micron-level assembly accuracy of the optical coupling structure 100.

[0108] In some embodiments, see Figure 8 and Figure 9 The optical coupling structure 100 further includes an optical device mounting portion 60. The optical device mounting portion 60 is disposed on a surface of the first substrate 101 that is away from the second substrate 102 and is located on the optical coupling surface S CL The back-total reflection surface S TR In this way, the optical device mounting portion 60 can be used to mount and fix the edge-emitting optical device on the light guide layer 10, so that the light-emitting surface of the optical device can be easily aligned with the light coupling surface S. CL Direct coupling.

[0109] The structure of the optical device mounting portion 60 can be adaptively configured according to the structure of the optical device to be mounted. For example, the optical device mounting portion 60 can be configured as Figure 8 The optical device carrier shown, or using Figure 9 The optical device receiving groove shown. This disclosure is not limited to this embodiment. Here, it is understood that in the example where the optical device mounting portion 60 adopts an optical device receiving groove, the optical device mounting portion 60 must also include an entity for forming the optical device receiving groove, such as the first substrate 101 or a protrusion on the surface of the first substrate 101.

[0110] Also, see Figure 8 In the example where the optical device mounting portion 60 is an optical device support platform, the optical device mounting portion 60 can be prepared independently and then assembled to the light guide layer 10, for example, by mechanical fixing methods such as welding and clamping.

[0111] See also Figure 9 In the example where the optical device mounting portion 60 is an optical device receiving groove, the optical device mounting portion 60 can be an integrated structure with the first base layer 101 and the guide protrusion 102, so that it is convenient to prepare it using a silicon wafer in a graphical manner, for example, etching the surface of the silicon wafer to form an optical device receiving groove for mounting the optical device.

[0112] Different optical devices have different mounting requirements. For this reason, please refer to Figure 10 and Figure 11In some embodiments, the optical coupling structure 100 further includes an optical device packaging cover 70. The optical device packaging cover 70 is disposed on a side of the optical device mounting portion 60 that is away from the first substrate 101 and is configured to package the optical device (e.g., the first optical device 1) mounted on the optical device mounting portion 60.

[0113] For examples, see Figure 10 The first optical device 1 is an optical fiber. The optical device mounting portion 60 is an optical device support platform, provided with a fiber accommodating groove. The optical device packaging cover 60 is a fiber cover plate. After the optical fiber is placed in the fiber accommodating groove of the optical device support platform, the fiber cover plate is bonded to the optical device support platform using glue or other adhesives. This allows the fiber cover plate to be used to securely hold the optical fiber. This simplifies the installation of the optical fiber on the optical coupling structure 100, thereby simplifying the docking process between the optical fiber and the optical coupling structure 100.

[0114] For examples, see Figure 11 The first optical device 1 is a laser. The optical device mounting portion 60 includes an optical device receiving groove. The optical device packaging cover 70 is a sealing cover. After the laser is installed in the optical device receiving groove, the sealing cover is used to seal the optical device receiving groove, thereby providing an enclosed working space for the laser, thereby preventing dust and moisture.

[0115] On this basis, considering the laser's need for a sealed environment and the docking conditions between the laser and the optical coupling structure 100, the guiding protrusions 102 of the light guiding layer 10 can also be set in a groove, and the groove and the laser's receiving groove can be connected to form a single groove. This can make the physical surface around the groove smooth, and thus make the sealing surface of the optical device packaging cover 70 smooth, further ensuring the sealing effect of the optical device packaging cover 70.

[0116] Also, please continue reading Figure 11 Optionally, the optical device packaging cover 70 is made of silicon material. The sealed connection between the optical device packaging cover 70 and the optical device mounting portion 60 is achieved by a ring-shaped closed sealing layer 71, but is not limited to this. The sealing layer 71 can be, for example, a metal sealing layer. The material of the metal sealing layer can be selected and set according to actual needs, and this embodiment of the present disclosure does not limit this.

[0117] In some embodiments, please refer to Figure 11The first optical device 1 is an active optical device such as a laser. The optical device mounting portion 60 further includes an electrode guide region 610. The electrode guide region 610 comprises an interconnected inner electrode 611 and an outer electrode 621. The orthographic projections of the inner and outer electrodes 611, 621 on the first substrate 101 are located on either side of the orthographic projection boundary of the optical device package cover 70 on the first substrate 101. The inner electrode 611 is configured to directly connect to the active optical device. The outer electrode 621 is configured to directly connect to an external power source.

[0118] Here, the inner electrode 611 is located in the enclosed space formed by the optical device packaging cover 70 and the optical device mounting portion 60. Before the first optical device 1 is sealed with the optical device packaging cover 70, the electrode of the first optical device 1 can be directly connected to the inner electrode 611, and then the first optical device 1 can be sealed with the optical device packaging cover 70. The outer electrode 621 is exposed on the outside of the optical device packaging cover 70 and can be directly connected to an external power source when needed. The interconnecting leads between the inner electrode 611 and the outer electrode 621 are usually hidden, that is, the surface of the leads of the two are usually covered with an insulating layer (not shown in the figure) to be insulated by the insulating layer. Therefore, the electrode guide area 610 can be used to simplify the connection operation between the active optical device and the external power source.

[0119] In addition, according to the different electrode polarities, the inner electrode 611 includes an inner positive electrode and an inner negative electrode, and the outer electrode 621 includes an outer positive electrode and an outer negative electrode. The inner positive electrode is connected to the positive electrode and the outer positive electrode of the first optical device 1, and the inner negative electrode is connected to the negative electrode and the outer negative electrode of the first optical device 1.

[0120] It is understood that in some of the above-described embodiments, the optical coupling structure 100 applied to different optical devices requires differentiated designs to improve the optical coupling efficiency between the different optical devices. For example, for optical devices with different optical mode field sizes, the optical coupling structure 100 can be designed with different microlenses to achieve the same optical mode field output size, thereby achieving higher optical coupling efficiency. For example, to address the polarization state variations of the optical signal transmitted by the optical fiber, the design of the optical coupling structure 100 can take into account both the TE polarization and the TM polarization of the optical signal to reduce polarization loss in the coupling.

[0121] Furthermore, when using co-sealed optical technology for multi-chip integration or packaging chips onto a system motherboard, it may be necessary to couple some components using a high-temperature process (e.g., reflow soldering). The optical coupling structure 100 in the disclosed embodiment can be mechanically connected to the corresponding components via the mechanical positioning structure 50, optical device mounting portion 60, etc., thereby preventing defects in the optical coupling structure 100 caused by high-temperature processes.

[0122] Some embodiments of the present disclosure also provide a method for preparing an optical coupling structure, which is used to prepare the optical coupling structure 100 as described above. Figure 1 and Figure 12 It is understood that the method for preparing the light coupling structure 100 includes S100 to S400.

[0123] S100 , a process step is performed on the wafer to form a light guide layer 10 . A plurality of guide bumps 102 are formed on the front side of the light guide layer 10 .

[0124] For example, a first wafer 1001 is provided, and a plurality of guide bumps 102 are formed on the front side of the first wafer 1001. Figure 12 As shown in FIG. (a) of FIG. 1 , the guide bump 102 includes: an optical coupling surface S perpendicular to the surface of the first wafer 1001; CL , and the optical coupling surface S CL The total reflection surface S is opposite to and formed at an angle α with the surface of the first wafer 1001. TR .

[0125] The first wafer 1001 is, for example, a silicon wafer. However, this is not the only option, and other light-transmitting substrates are also applicable. The plurality of guide bumps 102 can be prepared by a MEMS (Micro Electro Mechanical system) manufacturing process. For example, the front surface of the first wafer 1001 is patterned by an etching process to obtain the plurality of guide bumps 102. Dry etching has a high etching rate and causes minimal lateral erosion of the edges, so dry etching is used to prepare the optical coupling surface S of the guide bump 102. CL , which is not only easy to implement, but also ensures the optical coupling surface S CL The verticality between the surface of the first wafer 1001 and the surface of the first wafer 1001 is 0.0443 Wt etching has a higher etching accuracy, so wet etching is used to prepare the total reflection surface S TR , which can ensure the total reflection surface S TR The angle between the first wafer 1001 and the surface thereof satisfies the use, that is, ensures that the total reflection surface S TR molding accuracy.

[0126] S200 , performing a process step on the wafer to form a light collimating layer 20 , and forming a plurality of micro lenses 202 on the front side of the light collimating layer 20 .

[0127] For example, a second wafer 1002 is provided, and a plurality of grooves 203 and a micro lens 202 located in each groove 203 are formed on the front side of the second wafer 1002. Figure 12 As shown in Figure (b).

[0128] The second wafer 1002 is, for example, a silicon wafer. However, this is not limiting; other light-transmitting substrates are also suitable. The grooves 203 and microlenses 202 can be fabricated using a MEMS (Micro Electro Mechanical System) manufacturing process. For example, the front surface of the second wafer 1002 is patterned using an etching process to obtain a plurality of grooves 203 and corresponding microlenses 202 located within the grooves 203. The number, shape, and size of the grooves 203, as well as the shape, size, and characteristic parameters of the microlenses 202, can be selected and set according to actual needs and are not limited in the present embodiment.

[0129] There is no order restriction for S100 and S200; that is, they can be performed either before or simultaneously. However, it should be understood that in the optical coupling structure 100, there is a relative positional relationship between the guide bumps 102 and the microlenses 202. Therefore, the positions of the guide bumps 102 on the first wafer 1001 and the microlenses 202 on the second wafer 1002 need to be designed accordingly.

[0130] S300 , bonding the back side of the light guiding layer 10 and the back side of the light collimating layer 20 , and making one guiding bump 102 correspond to at least one microlens 202 .

[0131] For example, the back side of the first wafer 1001 and the back side of the second wafer 1002 are bonded, and one guide bump 102 is aligned with at least one micro lens 202, as shown in FIG. Figure 12 As shown in Figure (c).

[0132] The back side of the first wafer 1001 is opposite to its front side, which refers to its surface facing away from the guide bump 102. Similarly, the back side of the second wafer 1002 is opposite to its front side, which refers to its surface facing away from the microlens 202. There are many ways to join the back side of the first wafer 1001 and the back side of the second wafer 1002. For example, a metal pad is formed on the back side of the first wafer 1001, and the first wafer 1001 and the second wafer 1002 are welded together using the metal pad. Or, for example, optical glue is applied to the back side of the first wafer 1001 or the back side of the second wafer 1002, and the first wafer 1001 and the second wafer 1002 are bonded together using the optical glue. Or, for example, mechanical connection parts are prepared on the back side of the first wafer 1001 and the back side of the second wafer 1002, such as correspondingly provided card blocks and card slots, to achieve mechanical connection such as card connection.

[0133] In addition, before bonding the back side of the first wafer 1001 and the back side of the second wafer 1002, the back side of the first wafer 1001 or the back side of the second wafer 1002 may be thinned as required, which is not limited in the present embodiment.

[0134] After bonding the backside of first wafer 1001 to the backside of second wafer 1002, the correspondence between guide bumps 102 and microlenses 202 can be found in the aforementioned description of optical coupling structure 100 and will not be detailed here. Furthermore, bonding first wafer 1001 and second wafer 1002 can be performed using a high-precision die bonding machine for alignment and bonding.

[0135] S400 , obtaining a light coupling structure 100 , so that the light coupling structure 100 includes: a guide bump 102 , and at least one micro lens 202 corresponding to the guide bump 102 .

[0136] For example, the first wafer 1001 and the second wafer 1002 after being bonded are cut to obtain a plurality of optical coupling structures 100; wherein, an optical coupling structure 100 includes: a guide bump 102, and at least one micro lens 202 corresponding to the guide bump 102, such as Figure 12 As shown in Figure (d).

[0137] The bonded first wafer 1001 and second wafer 1002 are cut according to the distribution positions of the guide bumps 102 to obtain a plurality of dies, wherein one dies corresponds to one optical coupling structure 100 .

[0138] The method for fabricating the light coupling structure 100 provided in the disclosed embodiments can utilize a first wafer 1001 to independently fabricate guide bumps 102 to form the light guiding layer 10 in the light coupling structure 100; and utilize a second wafer 1002 to independently fabricate microlenses 202 to form the light collimating layer 20 in the light coupling structure 100. In other words, the light guiding layer 10 and the light collimating layer 20 are fabricated separately. Thus, depending on the different applications of the light coupling structure 100, a second wafer 1002 with suitable microlenses 202 can be selected for bonding to the first wafer 1001. This improves the versatility of the light guiding layer 10, thereby facilitating reduced production costs for the light coupling structure 100 in large-scale production.

[0139] In addition, the method for preparing the optical coupling structure provided in the embodiments of the present disclosure is used to prepare the optical coupling structure 100 in some of the aforementioned embodiments. The technical effects achieved by the aforementioned optical coupling structure 100 can also be achieved by this method, and will not be described in detail here.

[0140] In some embodiments, please combine Figure 5 、 Figure 13 and Figure 14 It is understood that the light coupling structure 100 further includes an anti-reflection film 30. Correspondingly, before executing S300, the method for preparing the light coupling structure 100 further includes: S110 and / or S210.

[0141] S110, such as Figure 13 As shown, at the optical coupling surface S CL The back-total reflection surface S TR An antireflection film 30 is formed on the surface of the substrate.

[0142] S210, such as Figure 14 As shown, an antireflection film 30 is formed on the front side surface of the microlens 202.

[0143] The antireflection film 30 is, for example, a silicon nitride film or a porous silicon dioxide film.

[0144] In some embodiments, please combine Figure 6 and Figure 15 It is understood that the surface of the guide bump 102 in the light guide layer 10 is provided with a metal reflective film 103. Correspondingly, before executing S300, the method for preparing the light coupling structure 100 further includes: S120.

[0145] S120, such as Figure 15 As shown, on the total reflection surface S of the guide protrusion 102 TR A metal reflection film 103 is formed thereon.

[0146] The metal reflective film 103 can be made of a metal material with high reflectivity such as gold, and formed by processes such as electroplating and sputtering.

[0147] In some embodiments, please combine Figure 6 and Figure 16 It is understood that the optical coupling structure 100 further includes a metal pad 40. The first base layer 101 and the second base layer 201 are connected via the metal pad 40. Accordingly, before executing S300, the method for preparing the optical coupling structure 100 further includes S130.

[0148] S130, such as Figure 16 As shown, patterned metal pads 400 are formed on the back side of the first wafer 1001 .

[0149] Here, the entire layer of patterned metal pads 400 covers the backside of first wafer 1001, with the openings corresponding to the locations of guide bumps 102, limited to not affecting the emission of the optical signals guided by guide bumps 102. After the dicing process in S400 is performed, the portion of patterned metal pads 400 located within each optical coupling structure 100 becomes the aforementioned metal pads 40 used to connect the first substrate 101 and the second substrate 102.

[0150] In addition, similarly, in other examples, patterned metal pads 400 are formed on the back side of second wafer 1002, and metal pads 40 can also be used to achieve bonding between first wafer 1001 and second wafer 1002. This embodiment of the present disclosure will not be further described in detail.

[0151] In addition, in some other examples, the first base layer 101 and the second base layer 201 are bonded together by optical adhesive, which will not be described in detail in the embodiments of the present disclosure.

[0152] In some embodiments, please combine Figure 7 and Figure 17 It is understood that the optical coupling structure 100 further includes: a mechanical positioning structure 50. Correspondingly, before executing S300, the method for preparing the optical coupling structure 100 further includes: S240.

[0153] S240, such as Figure 17 As shown, a plurality of mechanical positioning structures 50 are formed on the back side of the second wafer 1002 .

[0154] The structure and function of the mechanical positioning structure 50 are as described in the previous embodiments and will not be described in detail here.

[0155] In some embodiments, please combine Figure 8 、 Figure 9 、 Figure 18 and Figure 19 It is understood that the optical coupling structure 100 further includes an optical device mounting portion 60. The optical device mounting portion 60 adopts different structures and has corresponding different preparation methods.

[0156] In a possible implementation, the optical device mounting portion 60 is prepared independently. Thus, the optical coupling structure 100 can be mounted on a photonic chip or other planar optical device before being mounted on the light guiding layer 10. Figure 18 The method for preparing the optical coupling structure 100 further includes: S000, S500 and S600.

[0157] S000, independently prepare the optical device mounting portion 60, such as Figure 18 As shown in (a) in .

[0158] Here, there is no restriction on the order of S000 and S100 to S400, that is, they can be executed simultaneously or one by one.

[0159] S500, mounting the optical coupling structure 100 obtained in S400 on the second optical device 2, as shown in FIG. Figure 18 As shown in (b) in .

[0160] S600, assembling the optical device mounting portion 60 onto the light guide layer 10 of the optical coupling structure 100 by mechanical fixing means such as welding or clamping, as shown in FIG. Figure 18 As shown in (c) in .

[0161] Based on this, the optical device mounting portion 60 can be mounted in the light coupling structure 100 after the light coupling structure 100 undergoes a high temperature process.

[0162] In addition, the first optical device 1 and the optical device mounting portion 60 may be mounted first, and then the optical device mounting portion 60 may be mounted on the light guiding layer 10 of the light coupling structure 100 .

[0163] In another possible implementation, the optical device mounting portion 60 is an integral structure with the first base layer 101 and the guide bump 102. Accordingly, before executing S300, the method for preparing the optical coupling structure 100 further includes: S150.

[0164] S150, such as Figure 19 As shown, a plurality of optical device mounting portions 60 are formed on the front side of the first wafer 1001; wherein, one optical device mounting portion 60 is formed beside one guide protrusion 102 and is located at the optical coupling surface S CL The back-total reflection surface S TR side.

[0165] Based on this, the optical coupling structure 100 obtained after executing S400 further includes: an optical device mounting portion 60. The structure and function of the optical device mounting portion 60 are as described in the previous embodiments and will not be described in detail here.

[0166] In some of the aforementioned embodiments, Figure 10 and Figure 11 As shown, the optical coupling structure 100 further includes an optical device packaging cover 70. The optical device packaging cover 70 is independently manufactured, and its structure varies, requiring different manufacturing methods. When necessary, the independently manufactured optical device packaging cover 70 can be mounted on the corresponding optical device mounting portion 60. This disclosure will not be further described in detail in this embodiment.

[0167] It should be understood that, unless otherwise specified herein, some steps in the above-described method for preparing the light coupling structure 100 are not strictly limited in order. For example, steps S110, S120, S130, and S150 may be performed one by one or in another order depending on the structure of the light coupling structure 100 to be prepared. In other words, the order in which these steps are performed is not necessarily sequential.

[0168] Based on the aforementioned optical coupling structure 100, please refer to Figure 20 、 Figure 21 and Figure 22Some embodiments of the present disclosure further provide an optical component 1000. The optical component 1000 includes: at least one light emitter 3, at least one optical fiber 1-3, and an optical coupling structure 100 as described in any of the above embodiments. The optical fibers 1-3 correspond one-to-one to the light emitters 3. The light input ends of the optical fibers 1-3 are coupled to the corresponding light emitters 3, and the light output ends of the optical fibers 1-3 are coupled to the light coupling surface S of the light guide layer 10 in the optical coupling structure 100. CL Coupling.

[0169] The optical transmitter 3 is, for example, a transmitter optical subassembly (TOSA), in which a high-power laser is packaged. Figure 20 As shown in the multiple, or as Figure 22 The one shown in .

[0170] For examples, see Figure 20 and Figure 21 , there are multiple light emitters 3. That is, the optical coupling structure 100 can be coupled to the array of light emitters 3 simultaneously through multiple optical fibers 1-3. For example, multiple light emitters 3 are arranged in a row. The light input end of each optical fiber 1-3 is coupled to the corresponding light emitter 3. The light output end of each optical fiber 1-3 is mounted on the optical coupling structure 100 through the optical device mounting portion 60 and the optical device packaging cover 70. The end face of the light output end of each optical fiber 1-3 is aligned with the light coupling surface S of the light guide layer 10 in the optical coupling structure 100. CL There can be a gap between the two to ensure that the optical signal transmitted by the optical fiber 1-3 can reach the maximum power and be evenly transmitted from the optical coupling surface S CL Accordingly, the microlenses 202 of the light collimating layer 20 in the optical coupling structure 100 can be arranged in a one-to-one correspondence with the optical fibers 1-3 to achieve independent collimated emission of each optical signal.

[0171] Please continue reading Figure 20 and Figure 21 Optionally, the diameter of the optical output end of optical fiber 1-3 is smaller than the diameter of the optical input end of optical fiber 1-3, which facilitates long-distance fanning of multiple optical fibers 1-3. Thus, in the application of co-sealed optical technology, the fanning of each optical fiber 1-3 can be utilized to achieve long-distance coupling between the optical coupling structure 100 and the array of optical emitters 3. In other words, for large-scale device integration, the array of optical emitters 3 can be located in an area away from the core chipset, facilitating management of optical emitter 3 aging, reassembly, and heat dissipation.

[0172] For examples, see Figure 20The optical assembly 1000 further includes an adapter interface 4 disposed at the distal end of the optical fiber of the optical transmitter 3. The adapter interface 4 facilitates a pluggable connection between the optical transmitter 3 and an external device, thereby simplifying the assembly process between the optical assembly 1000 and the external device.

[0173] In some embodiments, the optical coupling structure 100 includes a transfer collimating layer and a transfer guiding layer. The optical component 1000 also includes an optical waveguide or photonic chip coupled to the transfer guiding layer. In this way, in large-scale device integration using co-sealed optical technology, some structures of the optical component 1000 can be coupled to the optical waveguide or photonic chip via the optical coupling structure 100 after high-temperature processing, thereby preventing adverse effects of the high-temperature process on the optical component 1000.

[0174] In the description of this specification, the various technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the various technical features of the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0175] The above-described embodiments merely represent several implementation methods of the present disclosure. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present disclosure, all of which fall within the scope of protection of the present disclosure. Therefore, the scope of protection of the patent disclosed herein shall be determined by the appended claims.

Claims

1. An optical coupling structure, characterized in that: include: A light guiding layer and a light collimating layer are stacked; The light guiding layer comprises: a first base layer, and a guiding protrusion provided on a surface of the first base layer facing away from the light collimating layer; the guiding protrusion has a light coupling surface and a total reflection surface; Wherein, the light coupling surface is perpendicular to the surface of the first base layer facing away from the light collimating layer; The total reflection surface is opposite to the light coupling surface and is arranged at an angle to the first base layer; The total reflection surface is configured to: totally reflect the optical signal coupled into the optical coupling surface to the optical collimation layer, so as to collimate or converge the optical signal through the optical collimation layer; or totally reflect the optical signal collimated or converged by the optical collimation layer to the optical coupling surface, so as to couple out through the optical coupling surface; Wherein, the light collimating layer comprises: A second base layer; the second base layer is located on a surface of the first base layer away from the guide protrusion; and, a microlens or an array thereof; the microlens or the array thereof is arranged on the second base layer.

2. The optical coupling structure according to claim 1, wherein: A groove is provided on a surface of the second base layer facing away from the first base layer; The microlens or the array thereof is disposed in the groove.

3. The optical coupling structure according to claim 1, wherein: The light transmission direction of the microlens or its array is perpendicular to the surface of the second substrate facing away from the first substrate; The orthographic projection of the microlens or its array on the second substrate at least partially overlaps with the orthographic projection of the total reflection surface on the second substrate.

4. The optical coupling structure according to claim 1, wherein: The first base layer and the second base layer are connected via a metal pad; the orthographic projection of the metal pad on the second base layer is outside the orthographic projection of the microlens or its array on the second base layer; Alternatively, the first base layer and the second base layer are bonded together by optical adhesive.

5. The optical coupling structure according to any one of claims 1 to 4, characterized in that: The optical coupling structure further includes: a mechanical positioning structure; The mechanical positioning structure is disposed on a surface of the second substrate facing away from the first substrate and is configured as an external optical device.

6. The optical coupling structure according to claim 5, wherein: The mechanical positioning structure includes at least one of a slot, a block, a positioning boss, a positioning hole or a positioning groove.

7. The optical coupling structure according to any one of claims 1 to 4, characterized in that: The optical coupling structure further includes: an optical device mounting portion; The optical device mounting portion is provided on a surface of the first base layer facing away from the second base layer and is located on a side of the light coupling surface facing away from the total reflection surface, and is configured to mount an optical device.

8. The optical coupling structure according to claim 7, wherein: The optical device mounting portion includes: an optical device supporting platform or an optical device accommodating groove.

9. The optical coupling structure according to claim 7, wherein: The optical coupling structure further includes: an optical device packaging cover; The optical device packaging cover is disposed on a side of the optical device mounting portion away from the first base layer, and is configured to package the optical device mounted on the optical device mounting portion.

10. The optical coupling structure according to claim 9, wherein: The optical device mounting portion is configured to mount an active optical device; The optical device mounting portion further includes: an electrode guide area; The electrode guide area includes: an interconnected inner electrode and an outer electrode, and the orthographic projections of the inner electrode and the outer electrode on the first base layer are respectively located on the inner and outer sides of the orthographic projection boundary of the optical device package cover on the first base layer; The inner electrode is configured to be directly connected to the active optical device, and the outer electrode is configured to be directly connected to an external power source.

11. The optical coupling structure according to any one of claims 1 to 4, characterized in that: The first base layer and / or the second base layer is a silicon base layer.

12. The optical coupling structure according to claim 11, wherein: The first base layer and the guide protrusion are an integrated structure; And / or, the microlens or the array thereof and the second base layer are an integrated structure.

13. The optical coupling structure according to any one of claims 1 to 4, characterized in that: The light guide layer further comprises: a metal reflective film disposed on the total reflection surface; The reflectivity of the metal reflection film is greater than the reflectivity of the total reflection surface.

14. The optical coupling structure according to any one of claims 1 to 4, characterized in that: The optical coupling structure further includes an anti-reflection film; The antireflection film is arranged on a surface of the light coupling surface away from the total reflection surface, and / or is arranged on a surface of the microlens or its array away from the total reflection surface.

15. The optical coupling structure according to claim 1, wherein: The optical coupling structure further comprises: a transfer collimating layer and a transfer guiding layer stacked on a surface of the optical collimating layer away from the optical guiding layer; wherein, The structure of the transfer collimating layer is the same as that of the light collimating layer. The transfer collimating layer is configured to: collimate or converge the optical signal transmitted by the light collimating layer into the transfer guiding layer, or collimate or converge the optical signal transmitted by the transfer guiding layer into the light collimating layer; The structure of the switching guide layer is the same as that of the light guide layer. The switching guide layer is configured to guide the light signal transmitted by the switching collimating layer to output, or guide the external light signal to be transmitted into the switching collimating layer.

16. A method for preparing an optical coupling structure, characterized in that: include: A first wafer is processed to form a light guiding layer, wherein a plurality of guiding bumps are formed on a front side of the light guiding layer; the guiding bumps include: a light coupling surface perpendicular to a surface of the first wafer; and a total reflection surface opposite to the light coupling surface and arranged at an angle to the surface of the first wafer; performing a process step on the second wafer to form a light collimating layer, wherein a plurality of micro lenses are formed on a front side of the light collimating layer; Joining the back side of the light guiding layer and the back side of the light collimating layer so that one of the guiding bumps corresponds to at least one of the microlenses; An optical coupling structure is obtained; wherein the optical coupling structure includes: one guide bump, and at least one microlens corresponding to the guide bump.

17. The method for preparing an optical coupling structure according to claim 16, wherein: The optical coupling surface is formed by a dry etching process, and the total reflection surface is formed by a wet etching process.

18. The method for preparing an optical coupling structure according to claim 16, wherein: Before bonding the back side of the light guiding layer and the back side of the light collimating layer, the preparation method further comprises: A metal reflection film is formed on the total reflection surface of the guide protrusion.

19. An optical component, characterized in that: include: at least one light emitter; At least one optical fiber; And, the optical coupling structure according to any one of claims 1 to 15; The optical fibers correspond to the light emitters one by one; the light input ends of the optical fibers are coupled to the corresponding light emitters, and the light output ends of the optical fibers are coupled to the light coupling surface of the light guide layer.

20. The optical assembly according to claim 19, wherein The diameter of the light output end of the optical fiber is smaller than the diameter of the light input end of the optical fiber.

21. The optical component according to claim 19 or 20, characterized in that The optical component further includes an adapter interface provided at the distal optical fiber end of the optical transmitter.

22. The optical assembly according to claim 19, wherein The optical coupling structure includes a switching collimating layer and a switching guiding layer; the optical component also includes an optical waveguide or a photonic chip coupled to the switching guiding layer.

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