Stacked laser array, photonic device and related applications

Abstract

The invention discloses a stacked laser array, a photonic device and related application, and relates to the technical field of high-speed optical communication, and the stacked laser array comprises a plurality of high-power laser arrays, a plurality of diamond substrates, a diamond carrier and an optical path coupling module. All the high-power laser arrays and the diamond substrates are stacked, a group of diamond substrates is arranged between every two adjacent groups of high-power laser arrays, and the high-power laser arrays and the diamond substrates are connected through bonding wires to form a stacked array; the stacked array is fixed on one side of the upper surface of the diamond carrier, the light path coupling module is fixed on the other side of the upper surface of the diamond carrier, and the high-power laser array is aligned with the light path coupling module. The high-power laser array is subjected to three-dimensional packaging by using a diamond material, and the integration level and the heat dissipation efficiency of the laser array are effectively improved through reasonable layout.

Description

Technical Field

[0001] The present invention relates to the technical field of high-speed optical communications, and more specifically to a stacked laser array, a photonic device and related applications. Background Art

[0002] With the continuous miniaturization of electronic products, the requirements for semiconductor packaging technology are becoming higher and higher, and smaller packaging sizes and higher integration density are needed. In order to improve the performance of electronic devices and reduce power consumption, packaging technology needs to support high-speed electrical signal transmission and have an effective heat dissipation mechanism. Traditional two-dimensional packaging technology has been unable to meet the needs of high-density integration, and three-dimensional packaging technology has emerged. By stacking multiple chips or devices, higher integration and performance can be achieved. Aluminum nitride is usually used as the substrate and TEC (Thermo-electric Cooler) is used for heat dissipation.

[0003] Laser arrays are often used in applications that require high-power output, such as material processing, communications, and medical treatment. Through stacked three-dimensional packaging, multiple laser chips can be integrated to increase overall output power, reduce space, and reduce system costs. Stacked packaging uses vertical interconnect technologies that can reduce interconnect resistance and capacitance, improve the quality of signal transmission, and help optimize the beam quality of the laser array. By precisely controlling the output beam of each laser chip, beam superposition and shaping can be achieved. At the same time, tighter interconnections can optimize the layout of optoelectronic devices and functional circuits, reduce signal transmission paths and delays, and improve the overall performance of the module.

[0004] However, although 3D packaging technology has many advantages in optical modules, it also faces some challenges: 3D packaging technology involves the cross-integration of multiple fields, such as microelectronics, optics, thermal, etc., which is technically difficult, and the stacked components and complex connection structures may increase the failure rate of the module, and effective reliability assurance measures need to be taken. At the same time, although 3D packaging technology significantly improves the integration and performance of optoelectronic systems by vertically stacking components, the direct consequence of high integration is the sharp increase in heat per unit volume, which puts higher requirements on the thermal management capabilities of the packaging structure. Especially for photonic devices, their high-efficiency conversion is often accompanied by a large amount of waste heat. If it is not dissipated in time, it will seriously affect the device performance and system reliability.

[0005] Therefore, how to improve the integration and heat dissipation efficiency of the laser array is an urgent problem to be solved by those skilled in the art. Summary of the invention

[0006] In view of this, the present invention provides a stacked laser array, photonic device and related applications, which utilizes diamond material to perform three-dimensional packaging of high-power laser arrays, and fully utilizes the performance advantages of high-power lasers through high heat dissipation and reasonable layout of bonding wires, thereby solving the problem of thermal crosstalk to a great extent, thereby making the distribution of various photonic devices more compact, and contributing to the miniaturization and integration of photonic chips.

[0007] In order to achieve the above object, the present invention adopts the following technical solution:

[0008] A stacked laser array comprises: a plurality of high-power laser arrays, a plurality of diamond substrates, a diamond carrier and an optical path coupling module; all the high-power laser arrays and the diamond substrates are stacked, a group of the diamond substrates is arranged between two adjacent groups of the high-power laser arrays, the high-power laser arrays and the diamond substrates are connected by bonding wires to form a stacked array; the stacked arrays are fixed on one side of the upper surface of the diamond carrier, and the optical path coupling module is fixed on the other side, and the high-power laser arrays are aligned with the optical path coupling module.

[0009] Preferably, each group of the high-power laser array is composed of a plurality of high-power lasers arranged in an arrangement. By setting different grating periods, each high-power laser generates a different lasing wavelength. The high-power lasers of different lasing wavelengths are arranged at equal intervals, thereby outputting a multi-wavelength light source to irradiate the optical path coupling module.

[0010] Preferably, a plurality of groups of interconnected microchannels arranged horizontally are provided inside the diamond substrate, and the plurality of groups of microchannels converge into an inlet and an outlet, and the inlet and the outlet penetrate the upper surface of the diamond substrate.

[0011] The technical effect of the above technical solution is that by circulating the cooling liquid through the internal microchannels, a hot and cold cycle is realized, which can quickly and effectively diffuse the high heat generated by the high-power laser array into the environment to the greatest extent, thereby reducing the impact of heat on the laser performance.

[0012] Preferably, the upper surface of the diamond substrate is coated with an upper thin film circuit, the lower surface is coated with a lower thin film circuit, and a through hole is provided on the side, the through hole connects the upper thin film circuit and the lower thin film circuit to realize vertical wiring; the high-power laser array is in contact with the upper thin film circuit or the lower thin film circuit and is connected through the bonding wire.

[0013] The technical effect of the above technical scheme is that the upper thin film circuit and the lower thin film circuit realize precise division of functional areas, through holes are made on both sides of the substrate, and the through holes are used to realize vertical conduction of the lines between the upper thin film circuit and the lower thin film circuit, and between the thin film circuit and the laser. Vertical wiring is realized through the double-layer thin film circuit, so that the circuit volume is extended in the three-dimensional direction to maximize the structural density; wherein, the high-power laser arrays on the upper and lower sides connect the electrodes to the upper thin film circuit and the lower thin film circuit respectively through bonding wires, and the thin film circuit is led to the through hole through the bonding wire, and the through hole itself leads out a bonding wire to the external current drive.

[0014] Preferably, a driving device and a liquid adding device are further provided, wherein the liquid adding device is connected to the inlet through the driving device, and the outlet is connected to the liquid adding device.

[0015] Preferably, the upper surface of the diamond carrier is coated with a carrier thin film circuit, and the high-power laser array is in contact with and connected to the carrier thin film circuit.

[0016] Preferably, the upper film circuit, the lower film circuit and the carrier film circuit are all gold-plated circuits, and their areas are larger than the high-power laser array. Gold has excellent electrical conductivity, and these specific areas are carefully designed to carry the circuit connection of the high-power laser, ensuring efficient and stable current transmission, thereby optimizing the performance and efficiency of the laser.

[0017] Preferably, the optical path coupling module includes a lens and an optical fiber array, the lens is vertically fixed on the upper surface of the diamond carrier, and the optical fiber array is fixed on a side of the lens away from the stacked array; the lens receives the light emitted by the high-power laser array and transmits it to the optical fiber array, and the optical fiber array transmits the received optical signal to an external device.

[0018] Preferably, the optical path coupling module includes a plurality of groups of the optical fiber arrays, and a group of the optical fiber arrays is horizontally aligned with a group of the high-power laser arrays, so as to ensure that the optical signals between different laser arrays do not crosstalk with each other, thereby ensuring more accurate optical signal transmission.

[0019] A photonic device comprises the stacked laser array as described above.

[0020] An application of the stacked laser array as described above in photonic devices to achieve miniaturization and integration.

[0021] Through the above technical solutions, it can be known that compared with the prior art, the present invention discloses a stacked laser array, photonic devices and related applications. In terms of structure, two batches of high-power laser arrays are integrated into the upper and lower sides of the same diamond substrate. At the same time, microchannels are made inside the diamond substrate, and coolant is injected. Through external drive, the coolant is driven to cycle hot and cold, and the heat generated by the high-power laser array is timely and efficiently extracted to the greatest extent, so as to maintain the stability of the temperature inside and around the laser, and improve the stability of the laser during operation. In addition, in order to solve the problem of electrical crosstalk between adjacent channels that is easy to occur between the bonding wires from the laser to the shell in the existing three-dimensional packaging, a TDV (Through Diamond Via) solution is proposed, that is, vertical conductive channels are made on both sides of the diamond substrate, and the number of channels depends on the design, so that the bonding wires required for powering the upper and lower lasers can be led to the same side. This design can make the bonding wire layout more reasonable and easy to manufacture. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0023] Figure 1 A front view of a stacked laser array provided by the present invention;

[0024] Figure 2 A top view of a stacked laser array provided by the present invention;

[0025] Figure 3 This is a right view of a stacked laser array provided by the present invention.

[0026] In the attached drawings: 1- high-power laser array, 21- upper thin film circuit, 22- lower thin film circuit, 23- carrier thin film circuit, 3- diamond substrate, 4- through hole, 5- diamond carrier, 6- optical fiber array, 7- lens, 8- microfluidic channel, 9- high-power laser, 10- inlet, 11- outlet. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] The embodiment of the present invention discloses a stacked laser array, such as Figure 1-3 As shown, it includes: a plurality of high-power laser arrays 1, a plurality of diamond substrates 3, a diamond carrier 5 and an optical path coupling module; all high-power laser arrays 1 and diamond substrates 3 are stacked, a group of diamond substrates 3 is arranged between two adjacent groups of high-power laser arrays, and the high-power laser array 1 and the diamond substrate 3 are connected by bonding wires to form a stacked array; the stacked array is fixed on one side of the upper surface of the diamond carrier 5, and the optical path coupling module is fixed on the other side, and the high-power laser array 1 is aligned with the optical path coupling module. The size of the high-power laser array 1 is smaller than the diamond substrate 3, and the size of the diamond substrate 3 is smaller than the diamond carrier 5; the strong optical signal brought by the high-power laser array 1 can reduce the accuracy requirements of the coupling between each photonic device and ignore the loss caused by some structures, thereby improving the performance of the photonic chip; the stacked package helps to optimize the beam quality of the laser array, and realizes the superposition and shaping of the beam by accurately controlling the output beam of each laser chip; the diamond material itself has a strong heat dissipation capacity, which can improve the efficiency of heat extraction.

[0029] Furthermore, each group of high-power laser arrays 1 is composed of a plurality of high-power lasers 9. By setting different grating periods, each high-power laser generates a different lasing wavelength. High-power lasers with different lasing wavelengths are arranged at equal intervals, thereby outputting a multi-wavelength light source to irradiate the optical path coupling module.

[0030] Furthermore, the high-power laser array uses III-V group quaternary compound semiconductor materials (such as InGaAsP / AlGaAsP, etc.) and is designed into a DFB laser array with a height of about 110um. Each laser has a high power output of more than 100mW. By designing different grating periods, each laser can generate a specific lasing wavelength. These lasing wavelengths are arranged at equal intervals to form a multi-wavelength light source for optical communication, which is particularly suitable for WDM (Wavelength Division Multiplexing) optical communication systems and can meet the needs of high-power, multi-wavelength transmission. The number of lasers in a high-power laser array varies with the design, such as Figure 3 The present embodiment shows an array design with 4 channels in the upper and lower parts, for a total of 8 channels.

[0031] Furthermore, a plurality of interconnected microchannels 8 are provided inside the diamond substrate 3 and converge to an inlet 10 and an outlet 11, and the inlet 10 and the outlet 11 penetrate the upper surface of the diamond substrate 3; the upper surface of the diamond substrate 3 is plated with an upper thin film circuit 21, and the lower surface is plated with a lower thin film circuit 22, and a through hole 4 (TDV) is provided on the side, and the through hole 4 connects the upper thin film circuit 21 and the lower thin film circuit 22 to realize vertical wiring; the high-power laser array 1 is in contact with the upper thin film circuit 21 or the lower thin film circuit 22, and is connected by bonding wires. A microchannel 8 is designed inside the diamond substrate 3, and the entrance of the channel is integrated on the upper surface of the diamond. A single integrated entrance differentiates multiple channels inside the diamond. Through an external driving device, the cooling liquid is driven to cycle hot and cold, so as to timely and efficiently extract the heat generated by the high-power laser array to the greatest extent, thereby reducing the influence of heat on the laser performance. At the same time, the bonding wires connecting the upper thin film circuit 21 and the electrode of the high-power laser array on the upper surface of the diamond substrate 3, the lower thin film circuit 22 and the electrode of the high-power laser array on the lower surface of the diamond substrate 3, the upper and lower thin film circuits and the TDV are connected through the TDV on the diamond substrate. The TDV can lead out a bonding wire to the external current drive, and integrate the circuits into the same plane (for example, the bonding wire led out from the TDV on the upper surface of the diamond substrate can provide the power required for the high-power laser arrays on the upper and lower sides), so as to realize the reasonable layout of the bonding wires. The number of TDVs varies with the design. In this embodiment, for example Figure 2 The design shown shows 4 through holes.

[0032] Furthermore, the diamond substrate 3 is a substrate made of diamond material, with a thickness of about 600um, and the upper and lower surfaces are gold-plated for making thin-film circuits. The thermal conductivity of diamond is extremely high, usually reaching 2000-2600W / (m·K), and is one of the substances with the highest thermal conductivity in nature. The use of diamond material as a substrate solves the problem of poor compatibility of lasers constructed by combining traditional semiconductor materials, metal materials and polymer materials. The surface metallization technology of diamond materials makes the integration between lasers and diamonds possible, and enhances the compatibility of diamonds with indium phosphorus materials. In addition, the microstructure processing technology of diamond materials can construct complex and fine microstructures on the surface of diamond. These microstructures not only optimize the heat conduction path and improve the heat dissipation efficiency, but also enhance the mechanical strength of diamonds; vertical conductive channels are basically made on diamonds to achieve three-dimensional packaging, which solves the problem that with the continuous increase in the number of bonding wires in traditional two-dimensional planar structure lasers, electrical crosstalk is prone to occur between adjacent channels, which seriously restricts the high-frequency performance of optical modules and also leads to the problem that the packaging density is difficult to further improve.

[0033] Furthermore, the number of channels of the microchannel 8 can be determined according to design requirements. Figure 1-2The example shown is a design with 6 channels. The coolant enters the 6 channels through an external drive device at the inlet and flows out uniformly after merging at the outlet, thus forming an efficient internal and external cold and heat circulation system. This design can timely and effectively export the heat generated by the laser.

[0034] Furthermore, the microchannel 8 is arranged in a horizontal direction, perpendicular to the high-power laser array 1 and TDV, and utilizes the excellent thermal conductivity of the diamond substrate 3 to quickly disperse and conduct the heat generated by the internal components of the chip to the external environment, thereby significantly reducing the chip temperature in a very short time and maintaining the temperature of the laser and the surrounding environment stable. This not only improves the working efficiency and stability of the laser, but also enables the high-power laser to be smoothly integrated into the photonic chip, greatly enhancing the overall performance and reliability of the photonic chip, effectively alleviating or even eliminating the thermal crosstalk phenomenon, and solving the thermal crosstalk problem in the three-dimensional packaging technology of the stacked laser array.

[0035] Furthermore, a liquid adding device is provided for storing cooling liquid, which is connected to the inlet 10 of the microchannel 8 and the outlet 11 via a driving device.

[0036] Furthermore, the upper surface of the diamond carrier is coated with a carrier thin film circuit, and the high-power laser array is in contact with and connected to the carrier thin film circuit.

[0037] Furthermore, the thin-film circuit is a fine gold coating on the surface of the diamond substrate 3 and the diamond carrier 5 to achieve precise division of functional areas. Given the excellent electrical conductivity of gold, these specific areas are carefully designed to carry the circuit connection of high-power lasers, ensuring efficient and stable current transmission, thereby optimizing the performance and efficiency of the laser. The structural design of thin-film circuits and TDV not only demonstrates the exquisite fusion of material science, but also greatly improves the overall operating efficiency of the laser system.

[0038] Furthermore, the diamond carrier 5 is made of diamond material, has a size in the order of centimeters, and is divided into different areas according to different photonic devices. Figure 1-2 The figure shows two module areas, namely the stacked array area and the optical path coupling module area. The purpose is to carry the entire optical path system and to carry a certain heat dissipation function. The stacked array area on the diamond carrier 5 is plated with a thin film circuit as an electrode at one end of the stacked laser array.

[0039] Furthermore, the optical path coupling module is composed of a lens and an optical fiber array, which plays a role in beam shaping and light transmission. The lens is vertically fixed on the upper surface of the diamond carrier, and the optical fiber array is fixed on the side of the lens away from the stacked array; the lens receives the light emitted by the high-power laser array and transmits it to the optical fiber array, and the optical fiber array transmits the received optical signal to an external device.

[0040] Furthermore, the optical path coupling module includes several groups of optical fiber arrays, and one group of optical fiber arrays is horizontally aligned with a group of high-power laser arrays, which can ensure that optical signals between different laser arrays do not crosstalk with each other, thereby ensuring more accurate optical signal transmission.

[0041] The three-dimensional packaged stacked laser array provided by the present invention is compared with the common two-dimensional packaged lasers currently on the market, and the main performance indicators of the two devices, including output power, wavelength stability and thermal stability, are tested using standard test methods. The test results show that under the same test conditions, the three-dimensional packaged stacked laser array provided by the present invention has higher output and, at a larger input current, the laser is less affected by thermal crosstalk, and has a higher degree of integration, and can significantly reduce the size of the package without sacrificing performance.

[0042] On the other hand, in a specific embodiment, a photonic device includes the aforementioned stacked laser array, which improves integration and achieves miniaturized design.

[0043] On the other hand, an application utilizing the aforementioned stacked laser array to achieve miniaturization and integration in photonic devices can effectively improve high-speed optical communication performance.

[0044] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0045] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A stacked laser array, characterized in that: include: Several high-power laser arrays, several diamond substrates, diamond carriers and optical coupling modules; All the high-power laser arrays and the diamond substrates are stacked, a group of the diamond substrates is arranged between two adjacent groups of the high-power laser arrays, and they are connected by bonding wires to form a stacked array; the stacked array is fixed on one side of the upper surface of the diamond carrier, and the optical path coupling module is fixed on the other side, and the high-power laser array is aligned with the optical path coupling module.

2. The stacked laser array according to claim 1, characterized in that: Each group of the high-power laser array is composed of a plurality of high-power lasers. By setting different grating periods, each high-power laser generates a different lasing wavelength. The high-power lasers with different lasing wavelengths are arranged at equal intervals, and the output multi-wavelength light source is irradiated to the optical path coupling module.

3. The stacked laser array according to claim 1, characterized in that: A plurality of groups of interconnected microchannels arranged horizontally are arranged inside the diamond substrate, and the plurality of groups of microchannels converge into an inlet and an outlet, and the inlet and the outlet penetrate the upper surface of the diamond substrate.

4. The stacked laser array according to claim 1, characterized in that: The upper surface of the diamond substrate is plated with an upper thin film circuit, the lower surface is plated with a lower thin film circuit, and a through hole is arranged on the side, the through hole connects the upper thin film circuit and the lower thin film circuit to realize vertical wiring; the high-power laser array is in contact with the upper thin film circuit or the lower thin film circuit and is connected through the bonding wire.

5. The stacked laser array according to claim 3, characterized in that: A driving device and a liquid adding device are also provided. The liquid adding device is connected to the inlet through the driving device, and the outlet is connected to the liquid adding device.

6. The stacked laser array according to claim 1, characterized in that: The upper surface of the diamond carrier is plated with a carrier thin film circuit, and the high-power laser array is in contact with and connected to the carrier thin film circuit.

7. The stacked laser array according to claim 1, characterized in that: The optical path coupling module includes a lens and an optical fiber array, wherein the lens is vertically fixed on the upper surface of the diamond carrier, and the optical fiber array is fixed on a side of the lens away from the stacked array; the lens receives the light emitted by the high-power laser array and transmits it to the optical fiber array, and the optical fiber array transmits the received optical signal to an external device.

8. The stacked laser array according to claim 7, characterized in that: The optical path coupling module includes a plurality of groups of optical fiber arrays, and a group of optical fiber arrays is horizontally aligned with a group of high-power laser arrays.

9. A photonic device, characterized in that: include: The stacked laser array according to any one of claims 1 to 8.

10. An application of the stacked laser array according to any one of claims 1 to 8 in a photonic device to achieve miniaturization and integration.

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