Optical module and electronic equipment

Abstract

The invention provides an optical module and electronic equipment, and relates to the technical field of optical communication. The optical module comprises a DSP module, a single laser, an optical modulator and a multi-path light emitting module. The optical modulator is connected with the DSP module, the single laser and the multi-path light emitting module. Wherein the DSP module is used for receiving an electric signal and converting the electric signal into a format matched with the multi-path light emitting module; the light modulator is used for coupling a single path of laser emitted by the single laser to the multi-stage Y branches and outputting the multi-stage Y branches through the multi-path light emitting module; wherein each stage of Y branch is used for dividing one path of laser into two paths of laser, and at least the splitting ratios of the first stage of Y branch are different. The optical module and the electronic equipment provided by the invention have the effects of lower cost and lower power consumption.

Description

Technical Field

[0001] This application relates to the field of optical communication technology, and more specifically, to an optical module and electronic device. Background Technology

[0002] With the rapid development of technologies such as data centers, cloud computing, artificial intelligence, and 5G communications, higher requirements are being placed on the bandwidth, power consumption, integration, and cost of optical interconnects. 800G optical modules have become a key component of the next generation of high-speed interconnects, especially in the DR4 (4-way parallel optical transceiver) architecture. Achieving high bandwidth, low power consumption, high reliability, and low cost has become a key focus of technological breakthroughs.

[0003] In existing technologies, 800G DR4 optical modules often employ a multi-laser solution, typically using four independent distributed feedback lasers (DFBs), each driving one optical channel. However, in this solution, the cost of the four lasers accounts for more than 35% of the total cost of the optical module, and the total power consumption usually exceeds 18W.

[0004] In summary, existing optical modules suffer from high cost and high power consumption. Summary of the Invention

[0005] The purpose of this application is to provide an optical module, optionally comprising a DSP module, a single laser, an optical modulator, and a multi-output optical module, wherein the optical modulator is connected to the DSP module, the single laser, and the multi-output optical module respectively; wherein... The DSP module is used to receive electrical signals and convert the electrical signals into a format that matches the multi-channel optical output module; The optical modulator is used to couple a single laser beam emitted by the single laser to a multi-level Y-branch and output the multi-level Y-branch through the multi-path output module; wherein each Y-branch is used to split a single laser beam into two laser beams, and at least the splitting ratio of the first-level Y-branch is different.

[0006] Optionally, the splitting ratio of the first-stage Y branch is 52:48.

[0007] Optionally, the optical modulator includes an electrode layer, a lithium niobate thin film layer, a bonding layer, and a silicon waveguide layer disposed layer by layer, wherein the thickness of the lithium niobate thin film layer is 300±10nm.

[0008] Optionally, the silicon waveguide layer includes P-regions and N-regions arranged side by side, wherein the doping concentration of the P-region is at least three times that of the N-region.

[0009] Optionally, the optical module further includes a temperature monitoring module, multiple thermocouples and micro heaters, wherein the thermocouples and micro heaters are located close to the single laser and the optical modulator, and both the thermocouples and micro heaters are connected to the temperature monitoring module; The temperature monitoring module is used to acquire the temperature data of the thermocouple and adjust the heating power of the micro heater based on the temperature data of the thermocouple.

[0010] Optionally, the heating power of the micro heater satisfies the formula:

[0011] Where P_heat represents heating power, Kp represents proportional gain, e(t) represents the difference between target temperature and actual temperature, Ki represents integral gain, Ki·∫e(t)dt represents integral term, Kd represents differential gain, and Kd·de(t) / dt represents differential term.

[0012] Optionally, when the Y branch includes three levels, the splitting ratio of the second-level Y branch and the third-level Y branch is dynamically adjustable, and the adjustable range is ±15%.

[0013] Optionally, the optical module further includes a microlens array, wherein the lasers are vertically stacked and coupled to the optical modulator through the microlens array.

[0014] Optionally, the single laser is a 1310nm distributed feedback laser.

[0015] On the other hand, this application also provides an electronic device, which includes the optical module described above.

[0016] Compared with the prior art, the embodiments of this application have the following beneficial effects: This application provides an optical module and an electronic device. The optical module includes a DSP module, a single laser, an optical modulator, and a multi-output module. The optical modulator is connected to the DSP module, the single laser, and the multi-output module. The DSP module receives electrical signals and converts them into a format compatible with the multi-output module. The optical modulator couples the single laser beam emitted by the single laser to multiple Y-branching stages and outputs the multiple Y-branching stages through the multi-output module. Each Y-branching stage splits one laser beam into two beams, and at least the first Y-branching stage has a different splitting ratio. Because this application uses a single laser for beam splitting instead of the traditional multiple lasers, the cost and power consumption of the laser are significantly reduced. Furthermore, the dynamic beam splitting technology using multiple Y-branching stages enables multi-channel power equalization, avoiding the calibration complexity and power inconsistency issues between multiple lasers.

[0017] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of an optical module provided in an embodiment of this application.

[0020] Figure 2 This is a schematic diagram of an optical power distribution network provided in an embodiment of this application.

[0021] Figure 3 This is a schematic diagram of a temperature monitoring module, multiple thermocouples, and a micro heater provided in an embodiment of this application.

[0022] Figure 4 This is a schematic diagram of the hierarchy of an optical modulator provided in an embodiment of this application.

[0023] Figure 5 This is an exemplary flowchart illustrating the fabrication method of an optical module provided in an embodiment of this application.

[0024] In the picture: 110-DSP module; 120-Single laser; 130-Optical modulator; 131-Silicon waveguide layer; 132-Binding layer; 133-Lithium niobate thin film layer; 134-Electrode layer; 140-Multi-channel light output module; 150-Electrical interface; 160-Temperature monitoring module; 170-Thermocouple; 180-Micro heater. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0026] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0027] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this application, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0028] It should be noted that in this paper, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0029] The following detailed description of some embodiments of this application is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0030] As described in the background section, current optical modules generally employ a multi-laser solution. For example, the 800G DR4 optical module uses four independent distributed feedback lasers, each driving an independent optical channel. While this architecture is relatively simple in design, it has several problems: 1. High cost: The laser and its supporting drive and temperature control circuits account for more than 35% of the module's material cost.

[0031] 2. Excessive power consumption: The total power consumption of the four lasers and their temperature control system is usually over 18W. In high-density deployment scenarios, the heat dissipation pressure is huge, which indirectly increases the energy consumption of the cooling system.

[0032] 3. Poor channel consistency: The inherent differences in wavelength, threshold current, slope efficiency, and thermal characteristics between different lasers make it difficult to maintain consistent optical power, extinction ratio, and wavelength across the four output channels. Even with precise factory calibration, these differences can be amplified under long-term operation and temperature cycling, leading to signal quality imbalances between channels. This necessitates complex dynamic compensation algorithms, increasing the burden and latency on the digital signal processor.

[0033] Furthermore, existing optical modules suffer from limitations in modulator bandwidth and efficiency. For example, achieving 200Gbps PAM4 modulation in a single channel requires extremely high electro-optic bandwidth. Traditional silicon-based Mach-Zehnder modulators (MZMs) rely on carrier dispersion effects, resulting in low modulation efficiency. Their 3dB bandwidth is typically limited to below 50GHz, making it difficult to meet the requirements of high-order modulation formats, and the EML scheme design is also quite complex.

[0034] Furthermore, existing optical modules suffer from thermal sensitivity and management complexity. An optical module is a high-density integrated microsystem containing multiple heat sources, including lasers, modulators, and detectors. Temperature fluctuations affect system performance through various physical mechanisms: the laser output wavelength drifts with temperature (typically around 0.1 nm / ℃), potentially deviating from the passband center of the wavelength division multiplexing filter. Experimental data shows that a 1℃ temperature fluctuation within the module can lead to a ±0.2dB deviation in output optical power. In multi-channel schemes, uneven heat distribution directly exacerbates performance differences between channels. Traditional global temperature control schemes (such as a single TEC controlling the temperature of the entire chip carrier) are slow to respond, have low accuracy, and cannot address localized hotspots within the chip.

[0035] In view of this, in order to solve the above problems, this application provides an optical module. Please refer to [link to relevant documentation]. Figure 1 The optical module includes a DSP module 110, a single laser 120, an optical modulator 130, and a multi-output optical module 140. The optical modulator 130 is connected to the DSP module 110, the single laser 120, and the multi-output optical module 140. The DSP module 110 is used to connect to the electrical interface 150 and to receive electrical signals, then convert the electrical signals into a format that matches the multi-output optical module 140. The optical modulator 130 is used to couple the single laser emitted by the single laser 120 to multiple Y branches and output the multiple Y branches through the multi-output optical module 140. Each Y branch is used to split one laser into two lasers, and at least the splitting ratio of the first Y branch is different.

[0036] Figure 1 In this context, the electrical interface 150 can be a multi-channel input. For example, for the 800G DR4 optical module, the electrical interface 150 is an 8-channel interface, which is used to connect 8 independent 100G electrical signals from the host side to the optical module. Each electrical signal may have one or more independent laser channels to realize the mapping of electrical signals to optical wavelengths.

[0037] The DSP module 110 is used to process and convert electrical signals. It can be a dedicated digital signal processor chip using an advanced 3nm process. The DSP module 110 receives eight parallel electrical signals from the host side (such as a switch ASIC), each with a signal rate of 100Gbps and using PAM4 modulation format. The primary function of the DSP module 110 is to perform retiming, reshaping, and error correction coding on these eight signals to compensate for signal loss and distortion during PCB trace transmission. Subsequently, the DSP module 110 combines the processed eight 100G signals in pairs, mapping and generating four 200G PAM4 digital drive signals. These four high-speed digital signals are output through the chip's built-in high-speed serializer and directly drive four parallel optical modulator 130 units located in the same package via extremely short gold wire bonding wires or microbumps. In addition, the DSP integrates a series of intelligent control functions, including data interaction with dynamic beam splitting and temperature control systems, module status monitoring, and a digital diagnostic interface supporting industry standards.

[0038] For the laser, this application employs a single light source, preferably a high-power distributed feedback laser with an output wavelength in the 1310nm window. This wavelength band was chosen primarily because of its low dispersion and low loss characteristics in single-mode fiber, making it suitable for short-distance data center interconnects. The DFB laser is specially designed to stably output optical power of no less than 70mW in continuous wave mode. The laser chip is flip-chip bonded or eutectic bonded to a sub-substrate with a heat sink to ensure efficient heat dissipation. The light emitted from the laser is coupled into the optical modulator 130.

[0039] The optical modulator 130 provided in this application integrates dynamic beam splitting and high-speed modulation functions on the same silicon photonic chip. For example, for an 800G DR4 optical module, a single high-power beam from a laser first enters a three-stage cascaded Y-branch tree network. This network is responsible for precisely and controllably distributing one input beam to four output ports, each corresponding to an independent modulator unit. The dynamic beam splitting characteristics are reflected in the fact that the splitting ratio of its second and third-stage Y branches can be finely adjusted in real time by an integrated microheater 180.

[0040] Furthermore, the four distributed optical signals enter four parallel Mach-Zehnder modulators (MZMs). Each MZM employs a unique lithium niobate thin film (LNOI)-silicon heterostructure to achieve a high bandwidth of 100 GHz and a low driving voltage. After the modulators load electrical signals, the four modulated optical signals are extracted from the chip and coupled into four parallel output optical fibers (i.e., the multi-output optical module 140) through an optical fiber array unit, completing the electro-optical conversion process.

[0041] The following uses the 800G DR4 optical module as an example to illustrate the optical splitting network provided in this application: Please see Figure 2 The optical power distribution network adopts a complete binary tree topology, consisting of three cascaded Y-branches. The first-level Y-branches split the input light into two paths; the second and third-level Y-branches further split these two paths into two, and finally, the third-level outputs four optical paths. Figure 2 In this design, a single laser X is input to a single laser source 120. In the first-stage Y-branch, laser X is split into X1 and X2. Simultaneously, the branch from X1 to X11 and X12 is used as the second-stage Y-branch, and the branch from X2 to X21 and X22 is used as the third-stage Y-branch, ultimately achieving the effect of splitting a single laser into four lasers. Of course, the beam splitting network described in this application is merely illustrative. In other implementations, the number of stages in the beam splitting network can be more or less; for example, a beam splitting network can also split a single laser into eight lasers.

[0042] Furthermore, the first-stage Y-branch is designed with an asymmetric fixed splitting ratio, meaning that the splitting ratios of the first-stage Y-branch are different. For example, the splitting ratio of the first-stage Y-branch is 52:48, meaning that after splitting laser X into X1 and X2, the ratio of the optical power of laser X1 to laser X2 is 52:48. This setting allows for pre-compensation of the actual splitting, compensating for inherent line losses. During splitting, the splitting is tilted; that is, the 52-ratio branch has losses, therefore the optical power is tilted. The purpose of this is to ensure that the output power of the four channels is as similar as possible.

[0043] Specifically, in the subsequent optical path, the optical signal will undergo waveguide transmission, modulator insertion, coupling, and other processes, all of which introduce losses. Due to slight asymmetries in the optical path layout and device characteristics, the losses of the upper and lower branches are not completely identical. By artificially introducing a controllable asymmetric beam splitting in the first stage, allowing the branch with slightly higher initial power to match the branch with slightly higher loss, the power reaching the four modulator inputs can be made as close as possible under static conditions (without dynamic adjustment), providing a good initial operating point for dynamic adjustment.

[0044] For the second and third stage Y branches, each Y branch in these two stages is designed with a dynamically adjustable splitting ratio, with an adjustable range of ±15%, thereby ensuring that the output power of the four channels is as similar as possible. The core of this design is the integration of a miniature thermo-optical tuner adjacent to one (or two) output waveguides of the Y branch. The dynamic adjustment of the splitting ratio is achieved through a tuning algorithm, which can be expressed as follows: def adjust_split_ratio(P_meas): P_target = 5.0# Target power (mW) k = 0.2# Heat adjustment coefficient delta = k * (P_target – P_meas) set_heater_power(H1, delta) # Adjust the microheater by 180 The feedback signal, P_meas (real-time measured power), serves as the feedback input for the system's output state. The setpoint, P_target (target power), is the desired steady-state state that the system aims to achieve.

[0045] Deviation calculation: (P_target - P_meas) calculates the deviation between the actual output and the target.

[0046] Control Response: The deviation value is multiplied by the proportional coefficient k to generate a control signal delta, which drives the actuator (micro heater 180) to adjust the output. The function of the proportional coefficient k: The larger the value of k, the faster the response speed, but it may cause oscillations (such as system overshoot when k=0.5).

[0047] The smaller the value of k, the smoother the response, but the longer the convergence time (e.g., when k=0.1, multiple adjustments are required).

[0048] In this application, k=0.2 is an empirical value, balancing response speed and stability.

[0049] Each tunable Y-branch's tuning function is achieved by a microheater 180. This heater uses a high-resistivity, thermally stable tantalum nitride thin film material, fabricated into a resistive structure using micro-nano processing techniques, and directly fabricated on the silicon dioxide cladding of the silicon photonic chip. Furthermore, the vertical distance between the microheater 180 and the underlying silicon waveguide core layer is strictly controlled to 2 ± 0.1 μm. This distance was optimized through simulation and experiments: too close a distance results in high heating efficiency but may introduce additional optical scattering losses; too far a distance leads to low thermal tuning efficiency and slow response. A distance of 2 μm achieves the optimal balance between tuning efficiency and optical performance. The heater's thermal time constant is designed to be in the sub-millisecond range (<1 ms), enabling the system to respond quickly to power fluctuations.

[0050] Meanwhile, the dynamic beam splitting employs a closed-loop feedback control process. Its goal is to maintain consistent optical power (P1, P2, P3, P4) across the four final output channels. Each of the four output fiber channels integrates a low-pump-ratio optical beam splitter and a PIN photodetector for real-time monitoring of the output optical power of each channel. .

[0051] To obtain real-time output optical power The algorithm calculates the deviations of these values ​​from the target power Ptarget. Simultaneously, based on a preset balancing strategy (such as minimizing the variance of the four-channel power), the algorithm determines the necessary adjustment to the splitting ratio of which Y branch and to what extent.

[0052] Based on the execution of the above code, the adjustment amount is converted into a voltage or power change (delta) applied to the corresponding microheater 180. For example, if channel 1 is found to have low power while channel 2 has high power, and both originate from the second-level Y branch, the control algorithm increases the heating power on the waveguide leading to channel 1 in that Y branch. Heating causes a local temperature increase in the waveguide, which in turn increases the refractive index of the silicon material (thermo-optic effect), thereby changing the interference conditions of light in that Y branch and "directing" more optical power to channel 1, achieving dynamic equilibrium.

[0053] The splitting ratio adjustment range of each adjustable Y branch is designed to be ±15% of the nominal value (e.g., 50:50). This range is sufficient to compensate for all static and slow-varying power imbalances caused by manufacturing tolerances, long-term aging, and changes in ambient temperature.

[0054] Based on this, please refer to Figure 3 The optical module also includes a temperature monitoring module 160, multiple thermocouples 170, and a micro heater 180. The thermocouples 170 and the micro heater 180 are located near the single laser 120 and the optical modulator 130. Both the thermocouples 170 and the micro heater 180 are connected to the temperature monitoring module 160. The temperature monitoring module 160 is used to acquire the temperature data of the thermocouples 170 and adjust the heating power of the micro heater 180 according to the temperature data of the thermocouples 170.

[0055] To ensure the stable operation of the aforementioned optical components under harsh environments, this application precisely arranges multiple high-precision nanothermocouples 170 as temperature sensors in key areas of the silicon photonic chip (such as near the two interference arms of each modulator, the Y-branch node, and the laser coupling point). For example, this application arranges eight thermocouples 170 near the single laser 120 and the optical modulator 130, forming a distributed micro-domain temperature control system. Simultaneously, a miniature tantalum nitride resistance heater is integrated next to each area requiring temperature control. An integrated temperature control module acquires data from all thermocouples 170 via a high-speed analog front-end, runs a PID control algorithm, independently calculates and drives the power of each micro-heater 180, thereby achieving independent, high-precision temperature stability across multiple micro-regions on the chip, thus ensuring channel power balance and long-term performance stability.

[0056] Taking eight distributed thermocouples 170 as an example, they can be set at the output coupling point of a single laser 120, at the first-stage Y branch, and near the two interferometer arms of each of the four modulators (a total of eight, but some positions can be reused). The thermocouple 170 signals are acquired by a high-precision, low-noise analog front-end chip and digitized at a rate of not less than 1 kHz before being transmitted to the temperature control processor.

[0057] The temperature monitoring module 160 implements independent PID control for each individual temperature control zone (such as the two arms of a modulator). Heating power Determined by the PID formula:

[0058] Where P_heat represents heating power, Kp represents proportional gain, e(t) represents the difference between the target temperature and the actual temperature, Ki represents integral gain, Ki·∫e(t)dt represents the integral term, Kd represents differential gain, and Kd·de(t) / dt represents the differential term. Furthermore, This represents the instantaneous temperature error.

[0059] For the proportional term It can provide instantaneous, proportional correction. For example, if a sudden increase in laser power causes a local temperature spike of 0.1°C, and Kp = 10 W / °C, this function will immediately output -1W (reducing heating) to counteract the temperature rise. In optical modules, it is used to quickly suppress sudden thermal disturbances caused by signal transients or changes in ambient airflow, preventing instantaneous spikes in optical power.

[0060] Integral term This technology is used to correct small, persistent temperature deviations and eliminate steady-state errors. Assuming a modulation arm has a persistent deviation of +0.02°C due to a slight asymmetry in package thermal resistance, the integral term accumulates this error over time. After 10 seconds, based on the accumulated error, +1W is output, and heating is gradually increased to eventually eliminate this 0.02°C steady-state deviation. This overcomes the slow power imbalance in the Y-branch waveguide caused by long-term thermal drift.

[0061] Differential term ( ) / This is used to proactively adjust based on the trend of error changes, suppressing system overshoot and oscillation. For example, if the temperature is rising at a rate of 0.01 ℃ / s, this outputs a correction signal before the error actually becomes large. For example, the output is +1W (increasing heating to slow the rising trend), which effectively prevents the modulator operating point from deviating from the quadrature point due to overshoot of the microheater 180, thus ensuring that the extinction ratio is always better than 6dB.

[0062] The solution provided in this application has the following beneficial effects: Regarding the issue of thermally induced channel imbalance: traditional solutions exhibit temperature fluctuations of ±1℃ and power deviations of ±0.2dB. In contrast, this application achieves a temperature control accuracy of ±0.05℃, a theoretical power deviation of ≤±0.03dB, and a measured deviation of ±0.3dB, effectively improving the thermally induced channel imbalance problem.

[0063] Regarding system reliability: The differential term suppresses overshoot, avoiding thermal cycling stress and extending the laser lifespan to MTTF > 1 million hours. The integral term eliminates steady-state deviation, preventing continuous power attenuation due to thermal drift after long-term operation.

[0064] High-speed transmission assurance: Stable temperature ensures a constant modulator bias point, a prerequisite for achieving low bit error rate PAM4 modulation. Experiments show that, under full temperature control, the system bit error rate of a 200G PAM4 signal can be stabilized below 1e-6.

[0065] Furthermore, to achieve high-density integration, the application employs a vertically stacked 3D SiP packaging form. The module also includes a microlens array, with the lasers vertically stacked and coupled to the optical modulator 130 via the microlens array. That is, the silicon photonics chip serves as the main body, optically interfaced with the laser chip placed vertically above it via the microlens array. All electrical interconnections are implemented through silicon adapters or flexible circuits. The entire optical engine is sealed within a hermetically tight metal or ceramic housing filled with an inert gas (such as nitrogen) to prevent corrosion from moisture and contaminants. Finally, this housing is integrated into a form factor conforming to QSFP-DD or OSFP standards, equipped with standard fiber optic connectors and electrical connectors, forming a pluggable complete module.

[0066] For the optical modulator 130, the optical modulator 130 provided in this application adopts an LNOI-silicon heterogeneous integrated modulator, which uses a "silicon-silicon dioxide-lithium niobate" vertical stacking scheme to form a layered heterostructure. As one implementation method, please refer to... Figure 4 The optical modulator 130 includes an electrode layer 134, a lithium niobate thin film layer 133, a bonding layer 132, and a silicon waveguide layer 131, which are disposed layer by layer. The thickness of the lithium niobate thin film layer 133 is 300±10nm.

[0067] The silicon waveguide layer 131 (220 nm thick) is based on a standard silicon-on-insulator wafer and is formed into a ridge or strip waveguide through electron beam lithography and reactive ion etching. This layer is responsible for low-loss light transmission and mode confinement. The silicon layer also serves as the substrate for subsequent PN junction formation.

[0068] In this application, after etching a silicon waveguide on a wafer, a PN junction is formed by ion implantation. Furthermore, the silicon waveguide layer 131 provided in this application employs an asymmetric doped PN junction design. The silicon waveguide layer 131 includes P-regions and N-regions arranged side-by-side. The doping concentration of the P-region is at least three times that of the N-region; for example, when boron ions are implanted into the P-region, the doping concentration is approximately 1 × 10⁻⁶. 18 cm 31×10 18 cm 3 The heavily doped region, the N region, is implanted with phosphorus ions, forming a concentration of approximately 5 × 10⁻⁶. 17 cm 35×10 17 cm 3 The doped regions.

[0069] The asymmetric doped PN junction design provides auxiliary thermo-optical tuning or low-speed bias control. Furthermore, the approximately 180±5nm spacing between the P-region and N-region edges optimizes the depletion region distribution under an applied reverse bias, allowing for greater overlap with the optical mode field. This results in a larger refractive index change at the same voltage, effectively reducing the required driving voltage.

[0070] The bonding layer 132 (thickness ~1μm) is made of silicon dioxide and is grown by plasma-enhanced chemical vapor deposition or thermal oxidation. In this application, the bonding layer 132 serves as both the lower cladding layer of the silicon waveguide and a stress buffer layer between the silicon and lithium niobate thin film layer 133, alleviating stress caused by the mismatch in thermal expansion coefficients between the two materials. Furthermore, the surface of the bonding layer 132 is flat to achieve better bonding performance.

[0071] The lithium niobate thin film layer 133 (thickness 300±10nm) is the core functional material layer. A single-crystal thin film can be obtained by dicing from a lithium niobate wafer and then bonded to the aforementioned silicon dioxide layer via a low-temperature plasma activation process. The 300nm thickness is optimized to ensure sufficient overlap between the optical field and the modulation electric field (high modulation efficiency), while also ensuring single-mode transmission conditions and achieving low-loss coupling with the underlying silicon waveguide.

[0072] Electrode layer 134 is a differentially driven traveling wave interdigitated electrode fabricated on a lithium niobate thin film using electron beam lithography, metal evaporation, and lift-off processes. The electrode gap is precisely controlled at 1.5 μm to match the optical waveguide mode size, while maintaining a characteristic impedance close to 50 Ω to achieve good broadband matching with the driving circuit.

[0073] Based on the above implementation, the present invention also provides a method for fabricating an optical module. Please refer to [link to relevant documentation]. Figure 5 The method includes the following steps: S1, Silicon Photonics Chip Fabrication: Waveguide layers and Y-branch structures are formed on SOI wafers through photolithography and etching; asymmetric PN junctions are formed through ion implantation and annealing; a silicon dioxide cladding is deposited and chemically and mechanically polished to flatten the surface.

[0074] S2, Heterogeneous Integration: The prepared thin-film lithium niobate wafer is plasma-activated and low-temperature bonded to the silicon dioxide layer of the silicon photonic chip; the lithium niobate is thinned and polished to the target thickness (300±10nm). Electrode and Heater Fabrication: Interdigitated electrodes are photolithographically etched and fabricated on the lithium niobate; tantalum nitride microheaters 180 are fabricated on the silicon dioxide cladding, with precise control over their distance from the waveguide.

[0075] S3, back-end process: trenching to expose the silicon waveguide end face, depositing an anti-reflection coating; dicing the wafer to obtain a single silicon photonic chip.

[0076] S4, Packaging and Assembly: The silicon photonics chip, laser, microlens, thermocouple 170 and other components are mounted and wire-bonded with high precision according to the above 3D scheme.

[0077] It is evident that the optical module provided in this application differs from existing optical modules at least in the following aspects: 1. System architecture level: This application adopts a combination of a single laser 120+ multi-level dynamically adjustable Y branch + parallel high-speed modulator array, while the existing technology adopts a traditional multi-laser parallel architecture.

[0078] 2. Device structure level: The specific layered heterogeneous integrated structure of silicon waveguide and asymmetric PN junction, silicon dioxide buffer layer, thin film lithium niobate and electrode layer 134 and its key size parameters (such as LNOI thickness of 300nm and PN spacing of 180nm).

[0079] 3. Control method level: Distributed micro-domain PID temperature control method applied to optical modules, and its connection with dynamic beam splitting closed-loop control.

[0080] 4. Integrated Packaging Level: 3D packaging method of vertically stacking lasers and coupling them with planar optical paths through microlenses, and its hermetic nitrogen-filled packaging process.

[0081] Based on the above implementation, this application also provides an electronic device, which includes the aforementioned optical module.

[0082] In summary, this application provides an optical module and an electronic device. The optical module includes a DSP module, a single laser, an optical modulator, and a multi-output module. The optical modulator is connected to the DSP module, the single laser, and the multi-output module. The DSP module receives electrical signals and converts them into a format compatible with the multi-output module. The optical modulator couples the single laser beam emitted by the single laser to multiple Y-bringers and outputs the multiple Y-bringers through the multi-output module. Each Y-bringer splits one laser beam into two beams, and at least the first Y-bringer has a different splitting ratio. Because this application uses a single laser for beam splitting instead of the traditional multiple lasers, the cost and power consumption of the laser are significantly reduced. Furthermore, the dynamic beam splitting technology using multiple Y-bringers enables multi-channel power equalization, avoiding the calibration complexity and power inconsistency issues between multiple lasers.

[0083] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

[0084] It will be apparent to those skilled in the art that this application is not limited to the details of the exemplary embodiments described above, and that this application can be implemented in other specific forms without departing from the spirit or essential characteristics of this application. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this application is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this application. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. An optical module, characterized in that, The optical module includes a DSP module, a single laser, an optical modulator, and a multi-output optical module. The optical modulator is connected to the DSP module, the single laser, and the multi-output optical module, respectively. The DSP module is used to receive electrical signals and convert the electrical signals into a format that matches the multi-channel optical output module; The optical modulator is used to couple a single laser beam emitted by the single laser to a multi-level Y-branch and output the multi-level Y-branch through the multi-path output module; wherein each Y-branch is used to split a single laser beam into two laser beams, and at least the splitting ratio of the first-level Y-branch is different.

2. The optical module as described in claim 1, characterized in that, The splitting ratio of the first-stage Y branch is 52:

48.

3. The optical module as described in claim 1, characterized in that, The optical modulator includes an electrode layer, a lithium niobate thin film layer, a bonding layer, and a silicon waveguide layer, which are arranged layer by layer. The thickness of the lithium niobate thin film layer is 300±10nm.

4. The optical module as described in claim 3, characterized in that, The silicon waveguide layer includes P-regions and N-regions arranged side by side, wherein the doping concentration of the P-region is at least three times that of the N-region.

5. The optical module as described in claim 1, characterized in that, The optical module also includes a temperature monitoring module, multiple thermocouples and micro heaters. The thermocouples and micro heaters are located close to the single laser and the optical modulator. Both the thermocouples and micro heaters are connected to the temperature monitoring module. The temperature monitoring module is used to acquire the temperature data of the thermocouple and adjust the heating power of the micro heater based on the temperature data of the thermocouple.

6. The optical module as described in claim 5, characterized in that, The heating power of the micro heater satisfies the formula: Where P_heat represents heating power, Kp represents proportional gain, e(t) represents the difference between target temperature and actual temperature, Ki represents integral gain, Ki·∫e(t)dt represents integral term, Kd represents differential gain, and Kd·de(t) / dt represents differential term.

7. The optical module as described in claim 1, characterized in that, When the Y branch includes three levels, the splitting ratio of the second-level Y branch and the third-level Y branch is dynamically adjustable, and the adjustable range is ±15%.

8. The optical module as described in claim 1, characterized in that, The optical module also includes a microlens array, the single lasers are stacked vertically and coupled to the optical modulator through the microlens array.

9. The optical module as described in claim 1, characterized in that, The single laser is a 1310nm distributed feedback laser.

10. An electronic device, characterized in that, The electronic device includes an optical module as described in any one of claims 1 to 9.

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