Optical communication device based on hybrid bonding photoelectric integration

Abstract

The invention provides an optical communication device based on hybrid bonding photoelectric integration. The optical communication device comprises a PCB, an RSOA chip, a passive Interposer, an optical chip, an electric chip and an optical fiber connector. The optical chip is directly bonded on the surface of the passive Interposer through a hybrid bonding technology; the passive Interposer, the optical chip, the RSOA chip and the electric chip are mounted on the PCB to form a 2D or 2.5 D packaging structure; the RSOA chip adopts a horizontal light emitting mode, the height of an optical waveguide layer of the RSOA chip is consistent with that of an optical waveguide layer of the optical chip, and coupling is realized through a matched waveguide design; and the electric chip is electrically connected with the electrode of the optical chip through the PCB and the re-wiring layer of the passive Interposer. According to the optical communication device, the RSOA chip, the optical chip and the electric chip which generate heat remarkably are decoupled and packaged on the PCB, so that centralized accumulation of heat is avoided, the thermal management design of the whole module is simplified, the influence of high temperature on the performance of the photoelectric device is effectively reduced, and the working stability and reliability of the optical communication device are remarkably improved.

Description

Technical Field

[0001] The present invention relates to the technical field of optoelectronic integrated chips and optical communication, and specifically, to an optical communication device based on hybrid-bonded optoelectronic integration. Background Art

[0002] With the rapid development of optical communication technology, the application requirements of optical modules in fields such as data centers and high-performance computing are increasing day by day, and higher requirements are put forward for their performance, including low power consumption, high integration, high bandwidth, high speed, low cost, and good versatility. The core components of an optical module usually include active and passive devices such as lasers (such as RSOA chips), detectors, modulators, wavelength division multiplexers / demultiplexers, etc., as well as the co-integration of optoelectronic chips. To achieve the above performance goals, advanced optoelectronic packaging technology has become the key, and problems such as the electrical interconnection efficiency between devices, signal integrity, thermal management, and large-scale production need to be solved.

[0003] The current mainstream optoelectronic integration solutions mainly adopt 2.5D or 3D packaging technologies based on TSV (through-silicon via) and TGV (through-glass via). Such technologies shorten the electrical interconnection distance through vertical vias, significantly improving the bandwidth and density of the integrated module while reducing power consumption. However, the existing technologies still have the following bottlenecks:

[0004] Material compatibility issues: Light sources, active / passive devices, and electrical chips are usually manufactured based on different material platforms (such as III-V semiconductors, silicon-based materials, lithium niobate, etc.). The differences in thermal expansion coefficients and process compatibilities between materials make hybrid integration difficult, affecting the yield and reliability.

[0005] Interconnection technology limitations: In traditional packaging, wire bonding technology is mostly used between chips. The parasitic inductance and capacitance introduced by it will deteriorate the high-frequency signal integrity and limit the bandwidth improvement. In addition, the physical length of wire interconnection is relatively long, making it difficult to meet the short-distance requirements of high-speed signal transmission.

[0006] Thermal management challenges: High-power devices such as RSOA chips in an optical module generate significant heat during operation. If directly stacked and integrated with other optoelectronic chips, it will cause a local temperature rise, affecting the stability and lifespan of the overall module. Existing 3D stacked packaging is difficult to achieve efficient heat dissipation due to thermal coupling problems.

[0007] Obstacles to large-scale production: Traditional packaging processes lack support for wafer-level integration and are difficult to meet the requirements of large-scale and low-cost production. There are limitations especially in the decoupled packaging and modular design of different functional chips.

[0008] In response to the above problems, Hybrid Bonding technology has gradually become a research hotspot. By simultaneously bonding the electrode and dielectric layers, this technology enables bump-free wafer-level vertical interconnection, which can not only significantly shorten the electrical interconnection distance and reduce parasitic effects, but also provide mechanical support and improve packaging reliability. In addition, hybrid bonding supports flexible integration between chips (Chip-to-Chip) and between wafers (Wafer-to-Wafer), providing a new technical path for co-packaged optics. However, how to optimize the packaging architecture of optical modules through hybrid bonding technology to achieve efficient decoupling of optoelectronic chips, optimized thermal management, and large-scale production remains a technical problem to be solved urgently. Summary of the Invention

[0009] Aiming at the defects in the prior art, the purpose of the present invention is to provide an optical communication device based on hybrid bonding optoelectronic integration.

[0010] An optical communication device based on hybrid bonding optoelectronic integration according to the present invention includes: a PCB, an RSOA chip, a passive Interposer, an optical chip, an electrical chip, and an optical fiber connector;

[0011] The optical chip is directly bonded to the surface of the passive Interposer through hybrid bonding technology; the passive Interposer, the optical chip, the RSOA chip, and the electrical chip are mounted on the PCB to form a 2D or 2.5D packaging structure; the RSOA chip adopts a horizontal light output mode, and its optical waveguide layer is at the same height as the optical waveguide layer of the optical chip, and coupling is achieved through a matching waveguide design; the electrical chip is electrically interconnected with the electrodes of the optical chip through the PCB and the redistribution layer of the passive Interposer.

[0012] Preferably, the passive Interposer includes:

[0013] Multiple through holes penetrating its upper and lower surfaces, and the through holes are filled with conductive materials;

[0014] Redistribution layers and electrodes provided on the upper and lower surfaces, and the redistribution layers achieve vertical electrical interconnection through the through holes;

[0015] The material of the passive Interposer is silicon or borosilicate glass, and its bonding surface has high flatness, and the bonding medium surface is higher than the electrode surface.

[0016] Preferably, the passive Interposer is a wafer-level or chip-level structure, and the packaging level of the optical chip is the same as that of the passive Interposer.

[0017] Preferably, the optical chip includes passive devices and active devices. The passive devices are selected from at least one of couplers, splitters, wavelength division multiplexers / demultiplexers, and the active devices are selected from modulators or detectors; the material of the optical chip is silicon, silicon nitride or lithium niobate.

[0018] Preferably, the optical fiber connector is directly connected to the optical chip or the passive Interposer, and the horizontal coupler cladding of the optical chip is integrated on the optical chip or the passive Interposer.

[0019] Preferably, the electrical chip is a driver chip or a transimpedance amplifier (TIA), and is mounted on the PCB or the passive Interposer and connected to the electrodes of the optical chip through a redistribution layer.

[0020] Preferably, the hybrid bonding technology includes: simultaneously bonding the electrodes and dielectric surfaces of the optical chip and the passive Interposer to form a vertical electrical connection structure without wire bonding, and the surface roughness of the bonding interface is less than 1 nm.

[0021] Preferably, the RSOA chip is a packaged III-V semiconductor chip, and its electrodes are powered through the redistribution layer of the PCB and realize optical signal input with the optical waveguide layer of the optical chip.

[0022] Preferably, the redistribution layers on the PCB and the redistribution layer of the passive Interposer realize multi-layer electrical signal transmission through vias and conductive material copper, and the interconnect distance is less than 100 μm.

[0023] Preferably, in the hybrid bonding interface between the optical chip and the passive Interposer, the thickness of the bonding medium is 5-20 nm, and the bonding strength is greater than 200 MPa.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] 1. By decoupling and packaging the significantly heat-generating RSOA chip, optical chip and electrical chip on the PCB, the present invention avoids the concentrated accumulation of heat, simplifies the thermal management design of the overall module, effectively reduces the influence of high temperature on the performance of optoelectronic devices, and thus significantly improves the working stability and reliability of the optical communication device;

[0026] 2. The present invention uses hybrid bonding technology to replace traditional wire bonding, realizes bump-free and short-distance vertical electrical interconnection, greatly reduces parasitic effects, shortens the electrical signal transmission path, ensures high-frequency signal integrity, and significantly improves the bandwidth performance of the optical communication module;

[0027] 3. Through the wafer-level or die-level hybrid bonding design of the passive Interposer, the present invention is compatible with the integration of optoelectronic chips of different sizes and material platforms, supports 2D / 2.5D packaging forms, meets the requirements of high-density wafer-level packaging, and can also adapt to small-scale die-level packaging scenarios, improving production flexibility and versatility. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Other features, objectives, and advantages of the present invention will become more apparent by reading the detailed description of the non-limiting embodiments with reference to the following drawings:

[0029] Figure 1 Stereoscopic schematic diagram of the optical communication module in Specific Embodiment 1 of the optical communication device based on hybrid bonding optoelectronic integration of the present invention;

[0030] Figure 2 Front view schematic diagram of the optical communication module in Specific Embodiment 1 of the optical communication device based on hybrid bonding optoelectronic integration of the present invention;

[0031] Figure 3 Stereoscopic schematic diagram of the optical communication module in Specific Embodiment 2 of the optical communication device based on hybrid bonding optoelectronic integration of the present invention;

[0032] Figure 4 Front view schematic diagram of the optical communication module in Specific Embodiment 2 of the optical communication device based on hybrid bonding optoelectronic integration of the present invention.

[0033] Wherein:

[0034] PCB 1 First optical waveguide layer 21

[0035] RSOA chip 2 Through-hole 31

[0036] Passive Interposer 3 Second electrode 32

[0037] Optical chip 4 Second optical waveguide layer 41

[0038] Electrical chip 5 Fiber optic connector 42

[0039] First electrode 11 Third electrode 43 DETAILED DESCRIPTION OF THE EMBODIMENTS

[0040] The present invention will be described in detail below with reference to specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that those of ordinary skill in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0041] Example 1:

[0042] like Figure 1 and Figure 2 As shown, it is specifically an optical communication device based on hybrid bonding optoelectronic integration. The specific structure includes PCB1, RSOA chip 2, passive Interposer 3, optical chip 4, optical fiber connector 42, and electrical chip 5. The optical chip 4 is hybrid bonded to the surface of the passive Interposer 3. The passive Interposer 3, optical chip 4, RSOA chip 2 and electrical chip 5 are mounted on PCB1 to realize 2D or 2.5D packaging.

[0043] A redistribution layer and a first electrode 11 matching the RSOA chip 2 , the passive interposer 3 and the electrical chip 5 are provided on the PCB 1 .

[0044] The passive Interposer 3 is provided with a plurality of through holes 31 for connecting the upper and lower surfaces of the passive Interposer 3. The upper and lower surfaces of the passive Interposer 3 are provided with a redistribution layer and a second electrode 32. The through holes 31 match the redistribution layer and the second electrode 32. The through holes are filled with copper as a conductive material. The material of the passive Interposer 3 can be silicon or borosilicate glass.

[0045] The optical chip 4 includes passive devices and active devices. The optical chip 4 can be a waveguide chip such as silicon, silicon nitride, lithium niobate, etc. The passive device can include passive device structures such as couplers, beam splitters, wavelength division multiplexing and demultiplexers. The active device can include active device structures such as modulators and detectors. The active device includes a third electrode 43 that matches the electrical chip.

[0046] The optical chip 4 is the same wafer-level as the passive Interposer 3.

[0047] The optical chip 4 needs to adopt a horizontal coupling mode. The cladding of the horizontal coupler of the optical chip 4 can be made on the optical chip 4. The optical fiber connector 42 is connected to the optical chip 4.

[0048] The optical chip 4 is electrically interconnected with the passive Interposer 3 via the third electrode 43 of the active device.

[0049] The surfaces of the medium to be mixed and bonded between the passive interposer 3 and the optical chip 4 have high flatness, are clean and free of contamination, and are slightly higher than the electrodes to be bonded.

[0050] Types of the electrical chip 5 include but are not limited to drivers and TIAs.

[0051] The electrical chip 5 is mounted on the PCB 1. Electrical interconnection with the optical chip 4 is achieved through matching electrodes with the redistribution layer and the first electrode 11 on the PCB 1, the through hole 31 on the passive interposer 3, the redistribution layer and the second electrode 32, and the third electrode 43 of the active device.

[0052] The types of RSOA chip 2 include but are not limited to packaged III-V semiconductor chips. RSOA chip 2 is electrically interconnected with PCB 1 through matching electrodes.

[0053] RSOA chip 2 needs to emit light in a horizontal manner, and achieve coupling from RSOA chip 2 to optical chip 4 by horizontal coupling. The first optical waveguide layer 21 of RSOA chip 2 and the second optical waveguide layer 41 of the optical chip have the same height. The two chips use matching waveguide design to achieve low-loss inter-chip coupling.

[0054] Example 2:

[0055] like Figure 3 and Figure 4 As shown, it is specifically an optical communication device based on hybrid bonding optoelectronic integration. The specific structure includes PCB1, RSOA chip 2, passive Interposer 3, optical chip 4, optical fiber connector 42, and electrical chip 5. The optical chip 4 is hybrid bonded to the surface of the passive Interposer 3. The passive Interposer 3, optical chip 4, RSOA chip 2 and electrical chip 5 are mounted on PCB1 to realize 2D or 2.5D packaging.

[0056] A redistribution layer and a first electrode 11 matching the RSOA chip 2 and the passive interposer 3 are provided on the PCB 1 .

[0057] The passive Interposer 3 is provided with a plurality of through holes 31 for connecting the upper and lower surfaces of the passive Interposer 3. The upper and lower surfaces of the passive Interposer 3 are provided with a redistribution layer and a second electrode 32. The through holes 31 match the redistribution layer and the second electrode 32. The through holes are filled with copper as a conductive material. The material of the passive Interposer 3 can be silicon or borosilicate glass.

[0058] The optical chip 4 includes passive devices and active devices. The optical chip 4 can be a waveguide chip such as silicon, silicon nitride, lithium niobate, etc. The passive device can include passive device structures such as couplers, beam splitters, wavelength division multiplexing and demultiplexers. The active device can include active device structures such as modulators and detectors. The active device includes a third electrode 43 that matches the electrical chip.

[0059] The optical chip 4 and the passive Interposer 3 are both die-level.

[0060] The optical chip 4 needs to adopt a horizontal coupling method. The cladding of the horizontal coupler of the optical chip 4 can be made on the passive Interposer 3. The optical fiber connector 42 is connected to the passive Interposer 3.

[0061] The optical chip 4 realizes electrical interconnection with the passive Interposer 3 through the third electrode 43 of the active device.

[0062] The surface of the medium to be hybrid-bonded of the passive Interposer 3 and the optical chip 4 has high flatness and the surface is clean and pollution-free. The surface of the medium to be hybridized is slightly higher than its bonding electrode.

[0063] The types of the electrical chip 5 include but are not limited to driver and TIA.

[0064] The electrical chip 5 is mounted on the passive Interposer 3. Electrical interconnection with the optical chip 4 is achieved through matching electrodes with the redistribution layer and the second electrode 32 on the passive Interposer 3 and the third electrode 43 of the active device.

[0065] The types of the RSOA chip 2 include but are not limited to packaged group III-V semiconductor chips. The RSOA chip 2 realizes electrical interconnection through matching electrodes and the PCB 1.

[0066] The RSOA chip 2 needs to emit light horizontally, and the coupling from the RSOA chip 2 to the optical chip 4 is achieved through a horizontal coupling method. The height of the first optical waveguide layer 21 of the RSOA chip 2 is the same as that of the second optical waveguide layer 41 of the optical chip. The two chips adopt a matching waveguide design to achieve low-loss inter-chip coupling.

[0067] Thus, an optical communication device based on hybrid-bonded optoelectronic integration is fabricated in different packaging ways. Through the hybrid-bonded optoelectronic packaging scheme, wire-free interconnection of optoelectronic chips is realized, the bandwidth is increased, the difficulty of thermal management is reduced, the working stability is improved, and it can better meet the production requirements of wafer-level and chip-level optoelectronic co-packaging modules and the usage needs of various application scenarios such as data centers and high-performance computing.

[0068] Example 3:

[0069] An optical communication device based on hybrid bonding optoelectronic integration provided by the present invention includes: a PCB 1, an RSOA chip 2, a passive Interposer 3, an optical chip 4, an electrical chip 5, and an optical fiber connector 42; the optical chip 4 is directly bonded to the surface of the passive Interposer 3 by a hybrid bonding technique; the passive Interposer 3, the optical chip 4, the RSOA chip 2, and the electrical chip 5 are mounted on the PCB 1 to form a 2D or 2.5D packaging structure; the RSOA chip 2 adopts a horizontal light output mode, and its first optical waveguide layer 21 is at the same height as the second optical waveguide layer 41 of the optical chip 4, and coupling is achieved through a matching waveguide design; the electrical chip 5 is electrically interconnected with the third electrode 43 of the optical chip 4 through the redistribution layer of the PCB 1 and the passive Interposer 3.

[0070] The passive Interposer 3 includes: a plurality of through holes 31 penetrating its upper and lower surfaces, and the through holes 31 are filled with a conductive material; a redistribution layer and a second electrode 32 are provided on the upper and lower surfaces, and the redistribution layer realizes vertical electrical interconnection through the through holes 31; the material of the passive Interposer 3 is silicon or borosilicate glass, and its bonding surface has high flatness, and the bonding medium surface is higher than the electrode surface.

[0071] The passive Interposer 3 is of a wafer-level or chip-level structure, and the packaging level of the optical chip 4 is the same as that of the passive Interposer 3. The optical chip 4 includes passive devices and active devices, and the passive devices are selected from at least one of a coupler, a beam splitter, and a wavelength division multiplexer / demultiplexer; the active devices are selected from a modulator or a detector; the material of the optical chip 4 is silicon, silicon nitride, or lithium niobate.

[0072] The optical fiber connector 42 is directly connected to the optical chip 4 or the passive Interposer 3, and the horizontal coupler cladding of the optical chip 4 is integrated on the optical chip 4 or the passive Interposer 3. The electrical chip 5 is a driver chip driver or a transimpedance amplifier TIA, and is mounted on the PCB 1 or the passive Interposer 3 and is connected to the third electrode 43 of the optical chip 4 through a redistribution layer.

[0073] The hybrid bonding technique includes: simultaneously bonding the electrodes and dielectric surfaces of the optical chip 4 and the passive Interposer 3 to form a vertical electrical connection structure without wire bonding, and the surface roughness of the bonding interface is less than 1 nm. The RSOA chip 2 is a packaged III-V semiconductor chip, and its electrodes are powered by the redistribution layer 11 of the PCB 1 and realize optical signal input with the second optical waveguide layer 41 of the optical chip 4.

[0074] The redistribution layer 11 on the PCB1 and the redistribution layer 32 of the passive Interposer 3 achieve multi-layer electrical signal transmission through vias 31 and the conductive material copper, and the interconnect distance is less than 100 μm. In the hybrid bonding interface between the optical chip 4 and the passive Interposer 3, the bonding medium thickness is 5-20 nm, and the bonding strength is greater than 200 MPa.

[0075] Those skilled in the art can understand this embodiment as a more specific illustration of Embodiment 1 and Embodiment 2.

[0076] Those skilled in the art know that in addition to implementing the system and its various devices, modules, and units provided by the present invention in the form of pure computer-readable program code, the method steps can be logically programmed to enable the system and its various devices, modules, and units provided by the present invention to be implemented in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers, etc., to achieve the same functions. Therefore, the system and its various devices, modules, and units provided by the present invention can be regarded as a hardware component, and the devices, modules, and units included therein for implementing various functions can also be regarded as the structure within the hardware component; the devices, modules, and units for implementing various functions can also be regarded as both software modules for implementing the method and the structure within the hardware component.

[0077] The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Without conflict, the embodiments of the present application and the features in the embodiments can be combined arbitrarily.

Claims

1. An optical communication device based on hybrid bonding optoelectronic integration, characterized in that, Including: A PCB (1), an RSOA chip (2), a passive Interposer (3), an optical chip (4), an electrical chip (5), and an optical fiber connector (42); The optical chip (4) is directly bonded to the surface of the passive Interposer (3) through a hybrid bonding technology; the passive Interposer (3), the optical chip (4), the RSOA chip (2), and the electrical chip (5) are mounted on the PCB (1) to form a 2D or 2.5D packaging structure; the RSOA chip (2) adopts a horizontal light output mode, and its first optical waveguide layer (21) is at the same height as the second optical waveguide layer (41) of the optical chip (4), and coupling is achieved through a matching waveguide design; the electrical chip (5) is electrically interconnected with the third electrode (43) of the optical chip (4) through the PCB (1) and the redistribution layer of the passive Interposer (3).

2. The optical communication device based on hybrid bonding optoelectronic integration according to claim 1, wherein The passive Interposer (3) includes: A plurality of through holes (31) penetrating its upper and lower surfaces, and the through holes (31) are filled with a conductive material; Redistribution layers and second electrodes (32) provided on the upper and lower surfaces, and the redistribution layers achieve vertical electrical interconnection through the through holes (31); The material of the passive Interposer (3) is silicon or borosilicate glass, and its bonding surface has high flatness, and the bonding medium surface is higher than the electrode surface.

3. The optical communication device based on hybrid-bonded optoelectronic integration according to claim 2, wherein, The passive Interposer (3) is of a wafer-level or chip-level structure, and the packaging level of the optical chip (4) is the same as that of the passive Interposer (3).

4. The optical communication device based on hybrid bonding optoelectronic integration according to claim 1, wherein The optical chip (4) includes passive devices and active devices, the passive devices are selected from at least one of a coupler, a beam splitter, and a wavelength division multiplexer / demultiplexer, and the active devices are selected from a modulator or a detector; the material of the optical chip (4) is silicon, silicon nitride, or lithium niobate.

5. The optical communication device based on hybrid bonding optoelectronic integration according to claim 1, wherein The optical fiber connector (42) is directly connected to the optical chip (4) or the passive Interposer (3), and the horizontal coupler cladding of the optical chip (4) is integrated on the optical chip (4) or the passive Interposer (3).

6. The optical communication device based on hybrid bonding optoelectronic integration according to claim 1, wherein The electrical chip (5) is a driver chip or a transimpedance amplifier TIA, and is mounted on the PCB (1) or the passive Interposer (3) and is connected to the third electrode (43) of the optical chip (4) through a redistribution layer.

7. The optical communication device based on hybrid bonding optoelectronic integration according to claim 1, wherein The hybrid bonding technology includes: simultaneously bonding the electrodes and dielectric surfaces of the optical chip (4) and the passive Interposer (3) to form a vertical electrical connection structure without gold wire interconnection, and the surface roughness of the bonding interface is less than 1 nm.

8. The optical communication device based on hybrid bonding optoelectronic integration according to claim 1, wherein The RSOA chip (2) is a packaged III-V semiconductor chip, and its electrodes are powered by the first electrode (11) of the PCB (1) and input optical signals to the second optical waveguide layer (41) of the optical chip (4).

9. The optical communication device based on hybrid-bonded optoelectronic integration according to claim 1, wherein The first electrode (11) on the PCB (1) and the second electrode (32) of the passive Interposer (3) achieve multi-layer electrical signal transmission through the via hole (31) and the conductive material copper, and the interconnection distance is less than 100 μm.

10. The optical communication device based on hybrid bonding optoelectronic integration according to claim 1, wherein, In the hybrid bonding interface between the optical chip (4) and the passive Interposer (3), the thickness of the bonding medium is 5-20 nm, and the bonding strength is greater than 200 MPa.

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