Vertical-cavity surface-emitting laser array and integrated system

Abstract

A vertical-cavity surface-emitting laser array (100) and an integrated system. The array (100) comprises: at least one laser (1), wherein the laser (1) comprises a substrate (11) and at least one first unit (12) located on the substrate (11); the first unit (12) comprises a laser emitting structure (121) and a connecting structure (122) located above the laser emitting structure (121); at least one light-emitting hole (121a) is formed in the laser emitting structure (121); the connecting structure (122) at least comprises a first electrode (122a) and a conductive heat dissipation layer (122b) that are sequentially stacked; the first electrode (122a) and the light-emitting hole (121a) are arranged opposite to each other; the conductive heat dissipation layer (122b) covers the first electrode (122a), and the orthographic projection of the light-emitting hole (121a) on the substrate (11) is located within the orthographic projection of the conductive heat dissipation layer (122b) on the substrate (11).

Description

A vertical cavity surface-emitting laser array and its integrated system

[0001] Cross-references to related applications

[0002] This disclosure claims priority to Chinese Patent Application No. 2025100711976, filed on January 16, 2025, entitled "A Vertical Cavity Surface Emitting Laser Array and Integrated System", the entire contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to the field of semiconductor technology, and in particular to a vertical cavity surface-emitting laser array and integrated system. Background Technology

[0004] With the development of artificial intelligence, the requirements for interconnect bandwidth and transmission rate of graphics processing units (GPUs) have increased. Traditional pluggable devices are gradually failing to meet the input / output requirements of GPUs in terms of bandwidth density, information power consumption and cost.

[0005] Currently, optoelectronic devices such as vertical-cavity surface-emitting lasers (VCSELs), silicon photonics laser emitters (SCPs), edge-emitting external-cavity tunable lasers (ECLs), and micro-LED arrays are mainly used to solve the aforementioned output problems. Among these, GPU input / output solutions based on VCSELs are the most promising technology because they combine single-channel bandwidth and two-dimensional integration, offering the best bandwidth density.

[0006] However, to realize the advantages of vertical-cavity surface-emitting lasers (VCSELs), a small emitter spacing is required. Traditional methods use metal guide electrodes, which protect the emitters but require a larger surface area, have poor heat dissipation, and result in unstable packaging structures. Summary of the Invention

[0007] According to various embodiments of the present disclosure, a vertical cavity surface-emitting laser array and integrated system are provided.

[0008] According to various embodiments of the present disclosure, a vertical-cavity surface-emitting laser array is provided, comprising:

[0009] At least one laser, the laser including a substrate and at least one first unit located on the substrate, the first unit including a laser emitting structure and a connecting structure located above the laser emitting structure, the laser emitting structure having at least one light-emitting hole, the connecting structure including at least a first electrode and a conductive heat dissipation layer stacked sequentially, the first electrode being disposed opposite to the light-emitting hole, the conductive heat dissipation layer covering the first electrode, and the orthogonal projection of the light-emitting hole on the substrate being located inside the orthogonal projection of the conductive heat dissipation layer on the substrate.

[0010] In some embodiments, the laser emitting structure includes a confinement layer and a confinement trench extending through the confinement layer, wherein the confinement trench surrounds the light-emitting aperture, and the orthographic projection of the confinement trench on the substrate is at least partially located within the orthographic projection of the conductive heat dissipation layer on the substrate.

[0011] In some embodiments, the laser emitting structure further includes an insulating layer that fills the limiting trench.

[0012] In some embodiments, the conductive heat dissipation layer further fills the limiting trench.

[0013] In some embodiments, the laser emitting structure is provided with a plurality of light-emitting holes, and two adjacent light-emitting holes share the adjacent limiting groove.

[0014] In some embodiments, the limiting grooves surrounding the light-emitting hole include a plurality of grooves that are spaced apart.

[0015] In some embodiments, the limiting groove surrounding the light-emitting hole includes one groove and is arranged in a ring shape.

[0016] In some embodiments, the connection structure further includes a first conductive post located on the upper surface of the conductive heat dissipation layer.

[0017] In some embodiments, the laser further includes at least one second unit located on the upper surface of the substrate and electrically connected to the first unit. The second unit includes at least a second electrode and a second conductive post, and the upper surface of the second conductive post is flush with the upper surface of the first conductive post.

[0018] In some embodiments, the second unit further includes a conductive pad located between the second conductive post and the second electrode.

[0019] In some embodiments, the conductive pad includes a first pad portion and a second pad portion, wherein the second pad portion is disposed in the same layer as the conductive heat dissipation layer.

[0020] In some embodiments, the laser includes a plurality of first units, the plurality of first units sharing a second unit, and the plurality of first units sharing the connection structure.

[0021] In some embodiments, the laser includes a plurality of the first units, the plurality of the first units sharing the second unit, or the plurality of the first units sharing the connection structure.

[0022] In some embodiments, the vertical cavity surface-emitting laser array includes a plurality of lasers, and the first units of the plurality of lasers share the connection structure, and the first units of the plurality of lasers share the second unit.

[0023] In some embodiments, the vertical cavity surface-emitting laser array includes a plurality of lasers, and the first unit among the plurality of lasers shares the connection structure, or the first unit among the plurality of lasers shares the second unit.

[0024] According to various embodiments of this disclosure, an integrated system is also provided, comprising:

[0025] The vertical cavity surface-emitting laser array and substrate described in any of the above embodiments are mounted on the substrate and electrically connected to the substrate.

[0026] In some embodiments, the integrated system further includes a driving structure, a signal conversion structure, and a signal amplification structure, and the driving structure, the signal amplification structure, and the signal conversion structure are all electrically connected to the substrate.

[0027] Details of one or more embodiments of this disclosure are set forth in the following drawings and description. Other features, objects, and advantages of this disclosure will become apparent from the specification, drawings, and claims. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments or conventional technologies of this disclosure, the accompanying drawings used in the description of the embodiments or conventional technologies will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 is a schematic diagram of the front cross-sectional structure of a vertical cavity surface-emitting laser array provided in one embodiment;

[0030] Figure 2 is a schematic diagram of the main cross-sectional structure of another vertical cavity surface-emitting laser array provided in one embodiment;

[0031] Figure 3 is a schematic diagram of the main cross-sectional structure of a third type of vertical cavity surface-emitting laser array provided in one embodiment;

[0032] Figure 4 is a top view cross-sectional diagram of a conductive heat dissipation layer and a limiting trench provided in one embodiment.

[0033] Figure 5 is a top view cross-sectional diagram of another conductive heat dissipation layer and limiting trench provided in one embodiment.

[0034] Figure 6 is a top view cross-sectional diagram of the third type of conductive heat dissipation layer and limiting trench provided in one embodiment.

[0035] Figure 7 is a schematic diagram of the arrangement structure of a vertical cavity surface-emitting laser array provided in one embodiment.

[0036] Figure 8 is a schematic diagram of the arrangement structure of another vertical cavity surface-emitting laser array provided in one embodiment.

[0037] Figure 9 is a schematic diagram of the arrangement structure of a third type of vertical cavity surface-emitting laser array provided in one embodiment.

[0038] Figure 10 is a schematic diagram of the arrangement structure of a fourth type of vertical cavity surface-emitting laser array provided in one embodiment.

[0039] Figure 11 is a schematic diagram of the arrangement structure of the fifth type of vertical cavity surface-emitting laser array provided in one embodiment.

[0040] Figure 12 is a schematic diagram of the arrangement structure of the sixth type of vertical cavity surface-emitting laser array provided in one embodiment.

[0041] Figure 13 is a schematic diagram of the arrangement structure of a laser provided in one embodiment.

[0042] Figure 14 is a schematic diagram of another laser arrangement structure provided in one embodiment.

[0043] Figure 15 is a schematic diagram of the arrangement structure of a third type of laser provided in one embodiment.

[0044] Figure 16 is a schematic diagram of the structure of an integrated system provided in one embodiment.

[0045] Figure 17 is a schematic diagram of another integrated system provided in one embodiment.

[0046] Figure 18 is a schematic diagram of the structure of a third integrated system provided in one embodiment.

[0047] To better describe and illustrate embodiments and / or examples of the inventions disclosed herein, reference may be made to one or more accompanying drawings. Additional details or examples used to describe the drawings should not be considered as limiting the scope of any of the disclosed inventions, the currently described embodiments and / or examples, or the best mode of these inventions as currently understood. Detailed Implementation

[0048] To facilitate understanding of this disclosure, a more complete description will now be given with reference to the accompanying drawings, in which preferred embodiments of the present disclosure are shown. However, this disclosure may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

[0049] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of this disclosure.

[0050] It should be understood that when an element or layer is referred to as "on," "adjacent to," "connected to," or "coupled to" other elements or layers, it may be directly on, adjacent to, connected to, or coupled to other elements or layers, or there may be intervening elements or layers. Conversely, when an element is referred to as "directly on," "directly adjacent to," "directly connected to," or "directly coupled to" other elements or layers, there are no intervening elements or layers. It should be understood that although the terms first, second, third, etc., may be used to describe various elements, parts, regions, layers, doping types, and / or portions, these elements, parts, regions, layers, doping types, and / or portions should not be limited by these terms. These terms are only used to distinguish one element, part, region, layer, doping type, or portion from another element, part, region, layer, doping type, or portion. Therefore, without departing from the teachings of this disclosure, the first element, part, region, layer, doping type, or portion discussed below may be referred to as a second element, part, region, layer, or portion.

[0051] Spatial relation terms such as “below,” “under,” “below,” “under,” “above,” “above,” etc., are used herein to describe the relationship between one element or feature shown in the figure and other elements or features. It should be understood that, in addition to the orientation shown in the figure, spatial relation terms also include different orientations of the device in use and operation. For example, if the device in the figure is flipped, the element or feature described as “below,” “under,” or “below” will be oriented “above” the other element or feature. Therefore, the exemplary terms “below” and “under” can include both above and below orientations. Furthermore, the device may also include other orientations (e.g., rotated 90 degrees or other orientations), and the spatial descriptive terms used herein will be interpreted accordingly.

[0052] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that when the terms “comprise” and / or “comprising” are used in this specification, the presence of the stated feature, integer, step, operation, element, and / or part is established, but the presence or addition of one or more other features, integers, steps, operations, elements, parts, and / or groups is not excluded. Meanwhile, when used herein, the term “and / or” includes any and all combinations of the associated listed items.

[0053] The related structures of the embodiments of this disclosure should not be limited to the specific shapes of the structures shown in the accompanying drawings, but should include shape deviations due to, for example, manufacturing techniques.

[0054] Please refer to Figures 1 to 3. This application provides a vertical-cavity surface-emitting laser array 100, including:

[0055] At least one laser 1, the laser 1 includes a substrate 11 and at least one first unit 12 located on the substrate 11. The first unit 12 includes a laser emitting structure 121 and a connecting structure 122 located above the laser emitting structure 121. The laser emitting structure 121 is provided with at least one light-emitting hole 121a. The connecting structure 122 includes at least a first electrode 122a and a conductive heat dissipation layer 122b stacked in sequence. The first electrode 122a is disposed opposite to the light-emitting hole 121a. The conductive heat dissipation layer 122b covers the first electrode 122a, and the orthogonal projection of the light-emitting hole 121a on the substrate 11 is located inside the orthogonal projection of the conductive heat dissipation layer 122b on the substrate 11.

[0056] The aforementioned vertical cavity surface-emitting laser array 100 forms a connection structure 122 directly above the laser emitting structure 121 in the laser 1. The conductive heat dissipation layer 122b of the connection structure 122 covers the first electrode 122a, and the orthogonal projection of the light-emitting aperture 121a on the substrate 11 is located inside the orthogonal projection of the conductive heat dissipation layer 122b on the substrate 11. Therefore, the connection structure 122 located above the laser emitting structure 121 can fully meet the heat dissipation problem during the operation of the laser emitting structure 121, effectively improving the heat dissipation performance of the laser 1, and also effectively reducing the size of the laser 1, realizing the fabrication of a high bandwidth density device. In some embodiments, the laser 1 is configured to include at least one first unit 12 and at least one second unit 13, with the upper surfaces of the first unit 12 and the second unit 13 flush and using the first unit... 12. The upper part of the second unit 13 serves as the electrode outlet, i.e., the same-side electrode layout is designed, which simplifies the wiring design, reduces the complex layout requirements for electrode connections, and lowers the process difficulty. Moreover, the same-side electrode design significantly shortens the distance between the anode and cathode, reduces parasitic resistance and capacitance, and helps to improve the operating speed and frequency response performance of the device. It also provides greater design freedom for multi-channel light-emitting arrays, making it easier to integrate the array and connect the driving circuit, thereby improving the bandwidth density of the device. In some embodiments, by designing the vertical cavity surface-emitting laser array 100 to include multiple lasers 1, and each laser 1 includes multiple first units 12, more light-emitting channels can be provided per unit area, thereby improving the bandwidth density and realizing a more compact optical communication module and consumer electronics product design with lower bandwidth density.

[0057] The substrate 11 provides mechanical support for other structures of the laser 1, serves as the basis for subsequent epitaxial growth and device fabrication, and is a conductive substrate, also providing a current path for the laser 1 to operate. The substrate 11 may be made of gallium arsenide, indium phosphide, silicon, or other suitable materials, and its size and shape may be selected according to actual conditions, without limitation, provided that the performance of the emitter is met.

[0058] As shown in Figures 1 to 3, the laser emitting structure 121 further includes a first reflective layer 121b, an active layer 121c, and a second reflective layer 121d, with the light-emitting hole 121a located between the second reflective layer 121d and the active layer 121c.

[0059] For example, the active layer 121c is composed of a direct bandgap semiconductor material, which can efficiently convert injected carriers (electrons and holes) into photons. The active layer 121c is made of gallium arsenide-based materials, indium phosphide-based materials, gallium nitride-based materials, or other suitable materials, and the active layer 121c employs one or more quantum well structures to optimize photoelectric conversion efficiency. The active layer 121c is the core region for realizing stimulated emission, where injected electrons and holes recombine in the quantum well, releasing photons with specific wavelengths. The active layer 121c is located between the first reflective layer 121b and the second reflective layer 121d, maximizing overlap with the optical mode of the resonant cavity to improve laser output efficiency.

[0060] For example, both the first reflective layer 121b and the second reflective layer 121d are composed of multiple alternating layers of high-refractive-index and low-refractive-index materials, with each layer having a thickness of 1 / 4 of the designed wavelength optical thickness to form Bragg condition multi-beam interference. The material of the first reflective layer 121b includes gallium arsenide-based materials, indium phosphide-based materials, titanium dioxide, silicon dioxide, or other suitable materials, and the material of the second reflective layer 121d includes gallium arsenide-based materials, indium phosphide-based materials, titanium dioxide, silicon dioxide, or other suitable materials. The thickness of layer 121d ranges from 3μm to 7μm. In this embodiment, the thickness of the second reflective layer 121d is 5μm. The first reflective layer 121b and the second reflective layer 121d act as high-reflectivity mirrors, working together with the active layer 121c in the region of the light-emitting aperture 121a to form a vertical resonant cavity. This allows photons generated by the active layer 121c to be reflected back and forth between the first reflective layer 121b and the second reflective layer 121d, forming laser light. This provides optical feedback for the laser emitting structure 121 and also optimizes laser performance. In this embodiment, the first reflective layer 121b is an N-type Distributed Bragg Reflection (N-DBR), and the second reflective layer 121d is a P-type Distributed Bragg Reflection (P-DBR).

[0061] Exemplarily, current is injected into the active layer 121c through the emission aperture 121a, and the emission aperture 121a confines the injected current to the central region of the active layer 121c. This avoids lateral current diffusion, reduces parasitic current, improves current utilization efficiency, lowers the threshold current of the laser 1, and improves the current-optical power characteristics. By adjusting the diameter of the emission aperture 121a, miniaturization and high power density of the vertical-cavity surface-emitting laser can be achieved. The diameter of the emission aperture 121a can be selected according to actual conditions, provided that the performance of the vertical-cavity surface-emitting laser is met; no limitation is imposed here.

[0062] For example, as shown in Figures 4 to 6, the laser emitting structure 121 includes a confinement layer 121e and a confinement trench 121f penetrating the confinement layer 121e. The confinement trench 121f surrounds the light-emitting aperture 121a, and the orthographic projection of the confinement trench 121f onto the substrate 11 is at least partially located within the orthographic projection of the conductive heat dissipation layer 122b onto the substrate 11. The confinement layer 121e is made of aluminum gallium arsenide with a high aluminum content, which is easily oxidized in a humid oxygen environment and can be converted into aluminum oxide to form a confinement layer 121e with insulating properties. The confinement layer 121e acts as an insulator in the structure, allowing current to pass only through the region of the light-emitting aperture 121a, concentrating charge carriers and photons in the region of the light-emitting aperture 121a, reducing unnecessary losses, improving current injection efficiency, lowering the threshold current, and improving the quantum efficiency of the laser. The confinement trench 121f can guide the lateral current to the region of the light-emitting aperture 121a, thereby optimizing the vertical injection path of the current, reducing the lateral diffusion of the current, and reducing parasitic current. Furthermore, while meeting the performance requirements of the vertical cavity surface-emitting laser, the opening size of the limiting groove 121f can be selected according to the actual situation and is not limited here. The distance between the sides of the limiting groove 121f near the light-emitting hole 121a ranges from 10μm to 15μm. In this embodiment, the distance between the sides of the limiting groove 121f near the light-emitting hole 121a is 13μm.

[0063] In some embodiments, as shown in Figures 4 and 5, the limiting grooves 121f surrounding the light-emitting hole 121a include a plurality of grooves that are spaced apart. Exemplarily, the shape of the limiting grooves 121f includes a trapezoid or other suitable shape.

[0064] In other embodiments, as shown in FIG6, the limiting groove 121f surrounding the light-emitting hole 121a includes one groove and is arranged in a ring. That is, by designing a suitable structure and shape for the limiting groove 121f, the lateral current can be effectively guided to the region of the light-emitting hole 121a, reducing the lateral diffusion of the current and lowering the parasitic capacitance.

[0065] In some embodiments, as shown in Figures 5 and 6, the orthographic projection of the sidewall of the limiting trench 121f away from the light-emitting hole 121a onto the substrate lies within the orthographic projection of the conductive heat dissipation layer 122b onto the substrate. That is, by providing the conductive heat dissipation layer 122b to fully cover the working area of ​​the laser emitting structure 121, the heat dissipation performance of the vertical cavity surface-emitting laser is fully guaranteed.

[0066] In other embodiments, as shown in FIG4, the orthogonal projection of the edge of the conductive heat dissipation layer 122b away from the light-emitting hole 121a onto the substrate lies within the orthogonal projection of the confinement trench 121f onto the substrate. That is, by setting the projection of the conductive heat dissipation layer 122b in the vertical direction to partially coincide with the projection of the confinement trench 121f in the vertical direction, the heat dissipation performance of the vertical cavity surface-emitting laser is satisfied, while the flexible structural design requirements of the vertical cavity surface-emitting laser are realized.

[0067] It should be noted that, while meeting the heat dissipation performance requirements of the vertical cavity surface-emitting laser, the orthographic projection of the conductive heat dissipation layer 122b on the substrate does not coincide with the orthographic projection of the confinement trench 121f on the substrate. That is, the orthographic projection of the conductive heat dissipation layer 122b on the substrate is located within the orthographic projection of the confinement trench 121f on the substrate. This can be selected according to the actual situation.

[0068] In some embodiments, the laser emitting structure 121 is provided with a plurality of light-emitting holes 121a, and two adjacent light-emitting holes 121a share an adjacent limiting groove 121f. This allows multiple light-emitting holes 121a to be set within a limited area, enabling the fabrication of a vertical cavity surface-emitting laser array 100 with higher bandwidth density, which is beneficial for higher output power density.

[0069] Exemplarily, the first electrode 122a provides a current path to inject current into the active layer 121c in the region of the light-emitting aperture 121a. The first electrode 122a also forms an ohmic contact, reducing the contact resistance of the device. In this embodiment, the first electrode 122a is a P-type ohmic metal. Furthermore, the first electrode 122a contributes to heat conduction, helping to maintain the operating temperature of the device. The material of the first electrode 122a includes at least one of gold, copper, silver, tin, and indium. The thickness of the first electrode 122a ranges from 0.1 μm to 0.5 μm. In this embodiment, the thickness of the first electrode 122a is 0.3 μm, and the first electrode 122a is a P-type ohmic metal.

[0070] For example, the conductive heat dissipation layer 122b covers the first electrode 122a, and the orthographic projection of the light-emitting hole 121a on the substrate 11 is located inside the orthographic projection of the conductive heat dissipation layer 122b on the substrate 11. This effectively reduces the size of the laser 1, enabling the fabrication of a high bandwidth density device. Simultaneously, during the operation of the laser emitting structure 121, it also adequately addresses heat dissipation issues, effectively improving the heat dissipation performance of the laser 1. The conductive heat dissipation layer 122b is made of at least one of gold, copper, silver, tin, and indium, or other suitable materials.

[0071] In some embodiments, as shown in Figures 1 and 2, the laser emitting structure 121 further includes an insulating layer 121g, which fills the confinement trench 121f. The insulating layer 121g is made of organic materials such as polymers and benzocyclobutene (BCB), or inorganic electrolyte materials such as silicon nitride and silicon oxide. Filling the confinement trench 121f with the insulating layer 121g not only restricts the lateral diffusion of the light field, improves the efficiency of current concentration injection into the light-emitting aperture 121a region, reduces parasitic current loss, and improves beam quality, but also avoids electric field interference and leakage current, improves electrical performance stability, and the insulating layer 121g also provides support for the connection structure 122 to enhance the mechanical stability and processing reliability of the device and alleviate the thermal stress of the laser 1 during operation.

[0072] Meanwhile, the conductive heat dissipation layer 122b is located above the insulating layer 121g, and multiple isolation layers 14 are provided between the conductive heat dissipation layer 122b and the insulating layer 121g. The material of the isolation layer 14 includes silicon nitride, which avoids direct contact between the conductive heat dissipation layer 122b and the insulating layer 121g, thereby avoiding any impact on the performance of the laser emitting structure 121. In addition, the multiple isolation layers 14 and the insulating layer 121g work together to provide support for the conductive heat dissipation layer 122b, alleviating the thermal stress problem during the operation of the laser 1.

[0073] In some embodiments, as shown in Figures 1 to 3, an ion implantation region 121h is further formed in the laser emitting structure 121. The ion implantation region 121h is located on the upper surface of the second reflective layer 121d and surrounds the light-emitting aperture 121a. The depth of the ion implantation region 121h is typically designed to be slightly less than or close to the total thickness of the second reflective layer 121d to ensure current confinement and optical waveguide effects. The implanted ions include hydrogen ions, oxygen ions, helium ions, boron ions, or other suitable implanted ions, and the distance between the ion implantation region 121h and the light-emitting aperture 121a is greater than 1 μm. In this embodiment, the ion implantation region 121h also surrounds a confinement trench 121f. The ion implantation region 121h and the confinement layer 121e work together to provide additional current and optical mode confinement in the lateral direction.

[0074] In other embodiments, as shown in FIG3, the conductive heat dissipation layer 122b is also filled within the confinement trench 121f. By filling the confinement trench 121f with the conductive heat dissipation layer 122b, the support stability of the conductive heat dissipation layer 122b is ensured, while further improving the heat dissipation performance of the conductive heat dissipation layer 122b. A multi-layer isolation layer 14 is provided between the active layer 121c at the bottom of the confinement trench 121f and the conductive heat dissipation layer 122b. The isolation layer 14 is made of silicon nitride, which prevents direct contact between the conductive heat dissipation layer 122b and the active layer 121c, thus avoiding any impact on the performance of the laser emission structure. Furthermore, the multi-layer isolation layer 14 provides support for the conductive heat dissipation layer 122b, alleviating the thermal stress problem during the operation of the vertical cavity surface-emitting laser.

[0075] In some embodiments, as shown in Figures 1 to 3, the connection structure 122 further includes a first conductive post 122c. The first conductive post 122c is located on the upper surface of the conductive heat dissipation layer 122b. The first conductive post 122c can serve as an external electrode. The material of the first conductive post 122c includes at least one of gold, copper, silver, tin, and indium, or other suitable materials. In this embodiment, the material of the first conductive post 122c includes copper. The first conductive post 122c serves as an anode for connecting current. The thickness of the first conductive post 122c ranges from 25μm to 35μm, and the width of the first conductive post 122c ranges from 35μm to 50μm. In this embodiment, the thickness of the first conductive post 122c is 30μm, and the width of the first conductive post 122c is 40μm.

[0076] The upper surface of the first conductive post 122c is further provided with a first welding layer 122d. The first welding layer 122d plays the role of electrical and mechanical connection in the subsequent packaging structure. The material of the first welding layer 122d includes at least one of silver and tin. The thickness of the first welding layer 122d ranges from 10μm to 15μm. In this embodiment, the thickness of the first welding layer 122d is 12μm, and the material of the first welding layer 122d is silver tin oxide.

[0077] In some embodiments, as shown in Figures 1 to 3, the laser 1 further includes at least one second unit 13, the second unit 13 being located on the upper surface of the substrate 11 and electrically connected to the first unit 12, the second unit 13 including at least a second electrode 131 and a second conductive post 132, and the upper surface of the second conductive post 132 being flush with the upper surface of the first conductive post 122c.

[0078] For example, the second electrode 131 is used to provide a current path to form a complete electrical connection path, enabling the laser 1 to operate normally. In this embodiment, the second electrode 131 is an N-type ohmic metal. The material of the second electrode 131 includes at least one of gold, copper, silver, tin, and indium. The thickness of the second electrode 131 ranges from 1 μm to 5 μm. In this embodiment, the thickness of the second electrode 131 is 2 μm.

[0079] For example, the second conductive post 132 serves as an external electrode, which is beneficial for the subsequent packaging of the laser 1. The material of the second conductive post 132 includes gold, copper, silver, tin, indium, or other suitable materials. In this embodiment, the material of the second conductive post 132 includes copper. The second conductive post 132 serves as a cathode for outputting current, and the thickness of the second conductive post 132 ranges from 25μm to 35μm, and the width of the second conductive post 132 ranges from 35μm to 50μm. In this embodiment, the thickness of the second conductive post 132 is 30μm, and the width of the second conductive post 132 is 40μm.

[0080] The upper surface of the second conductive post 132 is further provided with a second welding layer 134. The second welding layer 134 plays the role of electrical and mechanical connection in the subsequent packaging structure. The material of the second welding layer 134 includes at least one of silver and tin. The thickness of the second welding layer 134 ranges from 10μm to 15μm. In this embodiment, the thickness of the second welding layer 134 is 12μm, and the material of the second welding layer 134 is silver tin oxide.

[0081] By setting the upper surface of the second conductive post 132 to be flush with the upper surface of the first conductive post 122c, and setting the upper surface of the first unit 12 to be flush with the upper surface of the second unit 13, the packaging process can be carried out directly without the need for complex lead-out electrode structure design. This provides greater design freedom for multi-channel light-emitting arrays, making it easier to integrate the array and connect the driving circuit, and enabling the design of more compact optical communication modules and consumer electronics products with lower bandwidth density.

[0082] In some embodiments, the second unit 13 further includes a conductive pad 133, which is located between the second conductive post 132 and the second electrode 131. The conductive pad 133 serves as an intermediate layer that allows the second unit 13 to remain flush with the upper surface of the first unit 12. Exemplarily, the conductive pad 133 includes a first pad portion 133a and a second pad portion 133b, and the second pad portion 133b is disposed in the same layer as the conductive heat dissipation layer 122b. The material of the first pad portion 133a includes at least one of gold, copper, silver, tin, indium, or other suitable materials, and the thickness of the first pad portion 133a ranges from 7μm to 10μm. In this embodiment, the thickness of the first pad portion 133a is 8μm. The material of the second pad portion 133b includes at least one of gold, copper, silver, tin, indium, or other suitable materials, and the thickness of the second pad portion 133b ranges from 3μm to 6μm. In this embodiment, the thickness of the second pad portion 133b is 5μm.

[0083] The laser 1 also includes a contact layer 15, which is located above the substrate 11, and the first unit 12 and the second unit 13 are electrically connected through the contact layer 15.

[0084] In some embodiments, as shown in Figures 1 and 2, the contact layer 15 is located on the upper surface of the substrate 11, and the upper surface of the contact layer 15 is in contact with the first reflective layer 121b and the second electrode 131, respectively. By setting the contact layer 15 on the surface of the substrate 11, interference of the contact layer 15 with the optical cavity mode is avoided during laser emission from the back side of the substrate 11. Furthermore, the contact layer 15 directly contacts the second electrode 131, achieving ohmic contact and reducing the contact resistance of the device. The material of the contact layer 15 includes gallium arsenide, indium phosphide, transparent conductive oxide, or other suitable materials. The size and shape of the contact layer 15 can be selected according to actual conditions, provided that the performance of the vertical-cavity surface-emitting laser is met, and are not limited herein.

[0085] In other embodiments, as shown in FIG3, the contact layer 15 is located on the upper surface of the first reflective layer 121b, which is located on the upper surface of the substrate 11, and the upper surface of the contact layer 15 is in contact with the active layer 121c and the second electrode 131, respectively. By designing the contact layer 15 to be located on the upper surface of the first reflective layer 121b, the current injection is directly applied to the active region near the contact layer 15, resulting in a short current path, reduced current diffusion loss, and suitability for high-speed modulation and high-power designs.

[0086] In some embodiments, as shown in Figures 7 to 12, the vertical-cavity surface-emitting laser array 100 includes a plurality of lasers 1. The plurality of lasers 1 can be electrically isolated from each other during fabrication, enabling various flexible laser 1 arrangements. This allows for the placement of multiple lasers 1 within a limited area, achieving the fabrication of a vertical-cavity surface-emitting laser array 100 with higher bandwidth density, which is beneficial for higher output power density.

[0087] Furthermore, in some embodiments, the first units 12 in the plurality of lasers 1 share a common connection structure 122, and the first units 12 in the plurality of lasers 1 share a common second unit 13.

[0088] In other embodiments, the first units 12 in multiple lasers 1 share a common connection structure 122, or the first units 12 in multiple lasers 1 share a common second unit 13. That is, it is also possible to design the first units 12 in multiple lasers 1 to share a common anode, the first units 12 in multiple lasers 1 to share a common second unit 13, or the first units 12 in multiple lasers 1 to share a common anode, or the first units 12 in multiple lasers 1 to share a common second unit 13, thereby improving the luminous efficiency and system-level anti-interference capability of the vertical cavity surface-emitting laser array 100.

[0089] In some embodiments, as shown in Figures 12 to 15, the laser 1 includes a plurality of first units 12, the plurality of first units 12 sharing a second unit 13, and the plurality of first units 12 sharing a connection structure 122.

[0090] In other embodiments, the laser 1 includes multiple first units 12, which share a second unit 13, or multiple first units 12 share a connection structure 122. By including multiple first units 12 in the laser 1, it is beneficial to fabricate a vertical-cavity surface-emitting laser array 100 with higher bandwidth density, thus improving output power density. Furthermore, the structure of the laser 1 can be flexibly designed to meet different needs. For example, the laser 1 can include multiple first units 12, which share a second unit 13, i.e., when the second unit 13 is the cathode, the multiple first units 12 share a cathode; or the laser 1 can include multiple first units 12, which share a connection structure 122, i.e., when the first unit 12 is the anode, the multiple first units 12 share an anode. This shared anode or shared cathode configuration can give the laser 1 better luminous efficiency and system-level anti-interference capability. In this case, the second unit 13 can be shared, or there can be multiple second units 13. Simultaneously, the first units 12 and the second units 13 are electrically connected to ensure a complete current operating path.

[0091] In some embodiments, the lower surface of the substrate 11 of the first unit 12 is further integrated with a lens, grating or metasurface structure, which can further focus the laser light emitted by the laser emitting structure 121, effectively improve the beam quality and application effect, and the metasurface structure can also generate special beam patterns, which have important applications in optical manipulation and communication.

[0092] Please refer to Figures 16 to 18. This application also provides a chip integration system, including: a vertical cavity surface-emitting laser array 100 as described above and a substrate 200, wherein the vertical cavity surface-emitting laser array 100 is mounted on the substrate 200 and electrically connected to the substrate 200.

[0093] In some embodiments, the integrated system further includes a driving structure 300, a signal conversion structure 400, and a signal amplification structure 500, all of which are electrically connected to the substrate 200. The driving structure 300 provides sufficient driving current and driving voltage to the vertical-cavity surface-emitting laser array 100 to ensure that the vertical-cavity surface-emitting laser array 100 can operate normally. The signal conversion structure 400 is used to convert the optical signal emitted by the vertical-cavity surface-emitting laser array 100 into an electrical signal, and the signal amplification structure 500 is used to amplify the electrical signal.

[0094] In the packaging of the aforementioned integrated system, the laser 1 in the vertical cavity surface-emitting laser array 100 is arranged with electrodes on the same side, making it easier for the vertical cavity surface-emitting laser array 100 to directly interface with the substrate 200, improving the reliability of electrical connections, better meeting the requirements of planar design, reducing the number and complexity of packaging leads, simplifying chip-level and system-level packaging processes, and reducing stress concentration and damage risks in packaging.

[0095] In some embodiments, as shown in FIG16, the chip integration system further includes an interposer layer 700. The vertical cavity surface emission laser array 100, the driving structure 300, the signal amplification structure 500, and the signal conversion structure 400 are all electrically connected to the interposer layer 700 via solder pads 600. The interposer layer 700 is electrically connected to the substrate 200 via solder pads 600. The substrate 200 includes an electronic chip substrate.

[0096] In some other embodiments, as shown in FIG17, the chip integration system further includes an interposer layer 700. The vertical cavity surface emission laser array 100 and the signal amplification structure 500 are electrically connected to the interposer layer 700 via solder pads 600. The interposer layer 700 is electrically connected to the driving structure 300 and the signal conversion structure 400 below via solder pads 600. The driving structure 300 and the signal conversion structure 400 are fused with the substrate 200, which includes a computing chip.

[0097] In the third embodiment, as shown in FIG18, the vertical cavity surface emission laser array 100 and the signal amplification structure 500 are electrically connected to the driving structure 300 and the signal conversion structure 400 via solder pads 600 below, and the driving structure 300 and the signal conversion structure 400 are fused with the substrate 200, which includes a computing chip.

[0098] In the description of this specification, references to terms such as "some embodiments," "other embodiments," "ideal embodiments," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this disclosure. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.

[0099] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features of the above 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.

[0100] The embodiments described above are merely illustrative of several implementation methods of this application, and 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 those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A vertical-cavity surface-emitting laser array, comprising: At least one laser, the laser including a substrate and at least one first unit located on the substrate, the first unit including a laser emitting structure and a connecting structure located above the laser emitting structure, the laser emitting structure having at least one light-emitting hole, the connecting structure including at least a first electrode and a conductive heat dissipation layer stacked sequentially, the first electrode being disposed opposite to the light-emitting hole, the conductive heat dissipation layer covering the first electrode, and the orthogonal projection of the light-emitting hole on the substrate being located inside the orthogonal projection of the conductive heat dissipation layer on the substrate.

2. The vertical-cavity surface-emitting laser array according to claim 1, wherein, The laser emitting structure includes a confinement layer and a confinement trench penetrating the confinement layer, and the confinement trench surrounds the light-emitting hole. The orthographic projection of the confinement trench on the substrate is at least partially located within the orthographic projection of the conductive heat dissipation layer on the substrate.

3. The vertical-cavity surface-emitting laser array according to claim 2, wherein, The laser emitting structure also includes an insulating layer that fills the limiting trench.

4. The vertical-cavity surface-emitting laser array according to claim 2, wherein, The conductive heat dissipation layer is also filled within the limiting trench.

5. The vertical-cavity surface-emitting laser array according to claim 2, wherein, The laser emitting structure is provided with a plurality of light-emitting holes, and two adjacent light-emitting holes share the adjacent limiting groove.

6. The vertical-cavity surface-emitting laser array according to claim 2, wherein, The limiting grooves surrounding the light-emitting hole include a plurality of grooves and are spaced apart.

7. The vertical-cavity surface-emitting laser array according to claim 2, wherein, The limiting groove surrounding the light-emitting hole includes one and is arranged in a ring.

8. The vertical-cavity surface-emitting laser array according to claim 1, wherein, The connection structure further includes a first conductive post, which is located on the upper surface of the conductive heat dissipation layer.

9. The vertical-cavity surface-emitting laser array according to claim 8, wherein, The laser further includes at least one second unit, which is located on the upper surface of the substrate and is electrically connected to the first unit. The second unit includes at least a second electrode and a second conductive post, and the upper surface of the second conductive post is flush with the upper surface of the first conductive post.

10. The vertical-cavity surface-emitting laser array according to claim 9, wherein, The second unit also includes a conductive pad located between the second conductive post and the second electrode.

11. The vertical-cavity surface-emitting laser array according to claim 10, wherein, The conductive pad includes a first pad portion and a second pad portion, and the second pad portion is disposed in the same layer as the conductive heat dissipation layer.

12. The vertical-cavity surface-emitting laser array according to claim 9, wherein, The laser includes a plurality of first units, the plurality of first units sharing a second unit, and the plurality of first units sharing the connection structure.

13. The vertical-cavity surface-emitting laser array according to claim 9, wherein, The laser includes a plurality of first units, the plurality of first units sharing a second unit, or the plurality of first units sharing the connection structure.

14. The vertical-cavity surface-emitting laser array according to claim 9, wherein, The vertical cavity surface-emitting laser array includes a plurality of lasers, and the first unit of the plurality of lasers shares the connection structure, and the first unit of the plurality of lasers shares the second unit.

15. The vertical-cavity surface-emitting laser array according to claim 9, wherein, The vertical cavity surface emitter laser array includes multiple lasers, and the first unit of the multiple lasers shares the connection structure, or the first unit of the multiple lasers shares the second unit.

16. The vertical-cavity surface-emitting laser array according to claim 1, wherein, The laser emitting structure further includes a first reflective layer, an active layer, and a second reflective layer, with the light-emitting hole located between the second reflective layer and the active layer.

17. An integrated system, comprising: The vertical cavity surface-emitting laser array and substrate as described in any one of claims 1 to 16, wherein the vertical cavity surface-emitting laser array is mounted on the substrate and electrically connected to the substrate.

18. The integrated system according to claim 17, wherein, The integrated system further includes a driving structure, a signal conversion structure, and a signal amplification structure, and the driving structure, the signal amplification structure, and the signal conversion structure are all electrically connected to the substrate.

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