Chip and optical communication equipment

Abstract

The embodiment of the invention provides a chip and optical communication equipment, which are used for solving the technical problem of high cost of a chip in an optical communication module. The chip comprises a substrate, an insulating layer, a light-emitting component, a second waveguide, a modulator and a first coupler. And the light-emitting component is arranged in the groove of the insulating layer and is fixedly connected with the substrate, so that integration of the light-emitting component, the second waveguide, and the modulator and the first coupler which are arranged in the insulating layer is realized. And by adopting the mode of fixedly connecting with the substrate, the requirements on the flatness and smoothness of the light-emitting component and the surface of the substrate are low. An optical signal provided by the light-emitting component is transmitted to the modulator through the second waveguide, the optical signal processed by the modulator is transmitted to the first coupler, and the optical signal is output to the optical fiber. Compared with the prior art that the light-emitting component is arranged outside the chip, the chip provided by the embodiment of the invention does not need to be additionally assembled with an external light-emitting component, the assembly is simple, the cost of the chip can be reduced, and the yield of the chip is improved.

Description

[0001] This application is a divisional application. The original application was entitled "A Chip and an Optical Communication Device" and its application number was 202310096958.4. The original application date was January 18, 2023. The entire contents of the original application are incorporated herein by reference. Technical Field

[0002] This application relates to the field of semiconductor technology, and more particularly to a chip and an optical communication device. Background Technology

[0003] Data centers, comprising multiple servers and communication equipment, are used to transmit, accelerate, display, compute, and store data information over the Internet. Optical communication, with its advantages of ultra-high speed and ultra-high capacity, has been introduced into data center networks to achieve data transmission. With the transformation of network architecture, optical communication can be applied to short-range data transmission within data centers.

[0004] Data centers, categorized by functional architecture, can include an access layer, an aggregation layer, and a core layer. A short-range optical communication module is installed between any two layers. The chip in this module can receive optical signals from the input fiber and output optical signals to the output fiber. This allows data to flow between the different layers of the data center, achieving short-range optical communication.

[0005] As a crucial component for data transmission, reducing the cost of chips in short-range optical communication modules is an urgent issue to be addressed. Summary of the Invention

[0006] This application provides a chip and an optical communication device to solve the technical problem of high chip cost in optical communication modules.

[0007] To achieve the above objectives, the embodiments of this application adopt the following technical solutions:

[0008] In a first aspect, a chip is provided, comprising: a substrate, an insulating layer, a light-emitting component, a second waveguide, a modulator, and a first coupler; the insulating layer is formed on the substrate; a groove extending toward the substrate is formed on the surface of the insulating layer facing away from the substrate; the light-emitting component is disposed in the groove and fixedly connected to the substrate; a first waveguide is disposed in the light-emitting component; a second waveguide is disposed in the groove; the first waveguide and the second waveguide of the light-emitting component are coupled together; the modulator and the first coupler are both formed in the insulating layer; the modulator is coupled together with the second waveguide; the first coupler and the modulator are coupled together.

[0009] Based on the above description of the chip structure provided in the embodiments of this application, it can be seen that the chip includes a light-emitting component, which is disposed in a groove in an insulating layer and fixedly connected to the substrate, thereby integrating the light-emitting component, the second waveguide, and the modulator and the first coupler disposed in the insulating layer. By using a fixed connection to the substrate, the requirements for the flatness and smoothness of the light-emitting component and the substrate surface are lower, reducing the difficulty of the manufacturing process and thus reducing costs. In addition, besides providing mounting space for the light-emitting component, the groove can also limit the placement position of the light-emitting component to a certain extent, playing a positioning role, reducing the difficulty of fixing, and facilitating mass production.

[0010] The optical signal provided by the light-emitting component is transmitted to the modulator through the second waveguide. After being processed by the modulator, the optical signal is transmitted to the first coupler to output the optical signal to the optical fiber. Compared with placing the lens outside the chip as an external light-emitting component, the chip provided in this application embodiment does not require additional assembly of an external light-emitting component, simplifying assembly and reducing chip cost.

[0011] Furthermore, optical signal transmission is achieved through the coupling connection between the first and second waveguides within the light-emitting component, resulting in a simple structure. Compared to placing the light-emitting component outside the chip, the embodiments of this application provide a smaller distance between the first and second waveguides, resulting in lower coupling loss, lower chip loss, and improved optical power.

[0012] In a feasible implementation of the first aspect, the second waveguide is located between the light-emitting component and the substrate along a direction perpendicular to the substrate; the extension direction of the first waveguide is the same as the extension direction of the second waveguide; the orthographic projection of the first waveguide on the substrate at least partially coincides with the orthographic projection of the second waveguide on the substrate.

[0013] In this way, the first and second waveguides in the light-emitting component are positioned vertically along a direction perpendicular to the substrate, achieving an overlapping coupling structure through projection overlap. This enables evanescent wave coupling, resulting in a low insertion loss and high tolerance coupling effect. Insertion loss refers to the loss incurred by the device during optical signal transmission. High tolerance refers to the alignment tolerance of the light-emitting component's placement. This improves the chip yield.

[0014] In a feasible implementation of the first aspect, along the extension direction of the first waveguide, the second waveguide includes a first end that is away from the first waveguide; from the first waveguide to the first end, the width of the second waveguide first gradually increases and then gradually decreases.

[0015] In a feasible implementation of the first aspect, the light-emitting component has a first cavity surface perpendicular to the substrate, and the first cavity surface is an arc surface.

[0016] The curved surface can focus the light emitted by the light-emitting component, increasing the coupling efficiency with the second waveguide.

[0017] In a feasible implementation of the first aspect, the first coupler is disposed between the modulator and the light-emitting component along a direction parallel to the substrate.

[0018] In the feasible implementation of the first aspect, the second waveguide is located on the side of the modulator away from the substrate.

[0019] In a feasible implementation of the first aspect, the chip further includes: a photodetector and a second coupler; both the photodetector and the second coupler are formed in an insulating layer, and the photodetector and the second coupler are coupled together.

[0020] In this way, the light signal input from the optical fiber can be transmitted to the photodetector through the second coupler to complete the photodetection.

[0021] In the feasible implementation of the first aspect, the second waveguide is a passive waveguide.

[0022] Passive waveguides have low reflection loss, which is beneficial for achieving low loss in chips and increasing the optical power of chips.

[0023] In one feasible implementation of the first aspect, the material of the second waveguide includes silicon nitride.

[0024] Silicon nitride materials, when used in waveguides, offer advantages such as low transmission loss, low reflection, temperature insensitivity, and large process tolerance, resulting in excellent performance of the second waveguide.

[0025] In the feasible implementation of the first aspect, the first coupler is a passive device and the modulator is an active device.

[0026] In this way, the chip integrates passive and active components, enabling it to be applicable to a wider range of scenarios. The modulator exhibits an electro-optic effect. The first coupler is a passive component with low loss.

[0027] In the feasible implementation of the first aspect, the material of the first coupler includes silicon nitride; the material of the modulator includes silicon.

[0028] The first coupler is made of silicon nitride to achieve low on-chip return loss. The modulator is made of silicon to achieve high-speed performance and avoid lattice mismatch issues.

[0029] In one feasible implementation, the modulator material includes lithium niobate (LiNbO3). This allows for a higher speed modulator.

[0030] In a feasible implementation of the first aspect, the chip further includes: a heater; the heater is disposed within an insulating layer, and the heater is coupled to the modulator and the first coupler respectively.

[0031] The optical signal processed by the modulator is transmitted to the first coupler through the heater. The heater can control the temperature of a specific area on the chip, and adjust the refractive index of the waveguide by changing the temperature, thereby changing the optical phase in the waveguide.

[0032] In a feasible implementation of the first aspect, the chip further includes: a third waveguide located within an insulating layer, through which the first coupler is coupled to the modulator; the material of the third waveguide includes silicon nitride.

[0033] The third waveguide formed by silicon nitride can realize the coupling connection between the first coupler and the modulator, and has the advantage of low insertion loss.

[0034] In a feasible implementation of the first aspect, the light-emitting component includes a laser, which includes a grating and an active region; the grating is provided with a phase shift; the active region is coupled to a first waveguide; and the active region is formed between the grating and the second waveguide in a direction perpendicular to the substrate.

[0035] In a feasible implementation of the first aspect, the light-emitting component includes a laser, which includes: a substrate, a grating, and an active region; the grating is formed on the substrate; the active region is formed on the side of the grating away from the substrate; a first waveguide includes the active region; and the distance between the substrate and the substrate along a direction perpendicular to the substrate is greater than the distance between the active region and the substrate.

[0036] In this way, the laser can be fixed to the substrate via flip-chip bonding, simplifying the fabrication process and reducing costs. Furthermore, the laser has anti-reflective properties, eliminating the need for additional isolators on the chip, simplifying packaging and reducing costs.

[0037] In the first feasible implementation, the laser adopts a multi-ridge waveguide structure.

[0038] The structure of a multi-ridge waveguide can adapt to more application scenarios. For example, a multi-ridge waveguide can be configured with multiple channels of the same wavelength to meet the needs of DR (Diverter) applications. Alternatively, a multi-ridge waveguide can be configured with different wavelengths to meet the needs of FR (Frequency) applications.

[0039] In the feasible implementation of the first aspect, the grating is provided with a phase shift, the phase shift being... Or a biphase shift.

[0040] By selecting different phase shifts, it is possible to select a specific wavelength.

[0041] In a second aspect, this application provides an optical communication device, including: a chip and a circuit board as described in the first aspect, wherein the chip is disposed on the circuit board.

[0042] By setting the first aspect chip in the optical communication device, the conversion of photoelectric signals and the transmission of optical signals can be realized. It has the advantages of high power, high efficiency, high single-mode yield, high anti-reflection capability and low loss, and can be applied in a variety of application scenarios, such as short-distance application scenarios in data centers. Attached Figure Description

[0043] Figure 1 This is a schematic diagram of the structure of an optical communication system provided in an embodiment of this application;

[0044] Figure 2 This is a schematic diagram of the structure of a chip provided in an embodiment of this application;

[0045] Figure 3 This is a schematic diagram of the structure of a laser in a chip provided in an embodiment of this application;

[0046] Figure 4 This is a schematic diagram of the structure of a laser in a chip provided in an embodiment of this application;

[0047] Figure 5 This is a schematic diagram of a waveguide structure in a chip provided in an embodiment of this application;

[0048] Figure 6a A top view of one implementation of a chip provided in this application embodiment;

[0049] Figure 6b A top view of another implementation of a chip provided in this application embodiment;

[0050] Figure 7 This application provides a schematic diagram of the structure of a second waveguide and modulator in a chip.

[0051] Figure 8 This application provides a schematic diagram of the structure of a second waveguide and modulator in a chip.

[0052] Figures 9a to 9c A schematic diagram of the process structure of a chip provided in an embodiment of this application;

[0053] Figure 10 An optical path diagram of a silicon photonics chip DR4 (400G) provided in this application embodiment;

[0054] Figure 11 An optical path diagram of a silicon photonics chip DR8 (800G) provided in an embodiment of this application;

[0055] Figure 12 An optical path diagram of a chip FR4 provided in this application embodiment;

[0056] Figure 13An optical path diagram of a 2* chip FR4 is provided for an embodiment of this application.

[0057] Figure label:

[0058] 1-Optical communication system,

[0059] 100 - Optical switch, 200 - Optical module

[0060] 110-Chip, 111-Light-emitting component, 111a-First waveguide, 111b-First cavity surface, 111c-First electrode, 1101-Substrate, 1102-Grate, 1103-Active region, 1130-Coupling conversion structure, 112-Modulator, 112a-Second part, 113-Photodetector, 114-Heater

[0061] 120 - Fiber optic array unit, 121 - Output fiber, 122 - Input fiber.

[0062] 130 - Conversion chip, 131 - Optical communication digital signal processing module, 132 - Driver module, 133 - Transimpedance amplifier.

[0063] 10-Substrate, 10a-Channel

[0064] 20-Insulating layer, 20a-Surface, 201-Groove, 21-First insulating layer, 22-Second insulating layer

[0065] 30 - Second waveguide, 30a - First part

[0066] 40 - First Coupler

[0067] 50 - Second Coupler

[0068] 70 - Welding point

[0069] 80-electrode pair,

[0070] 90 - Stop block. Detailed Implementation

[0071] The technical solutions of the embodiments of this application will be described below with reference to the accompanying drawings. In the description of this application, unless otherwise stated, " / " indicates that the objects before and after are in an "or" relationship. For example, A / B can represent A or B. "And / or" in this application is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, and B alone, where A and B can be singular or plural. Furthermore, in the description of this application, unless otherwise stated, "multiple" refers to two or more. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can represent: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or multiple. Furthermore, to facilitate a clear description of the technical solutions in the embodiments of this application, the terms "first" and "second" are used in the embodiments of this application to distinguish identical or similar items with substantially the same function and effect. Those skilled in the art will understand that the terms "first" and "second" do not limit the quantity or execution order, and that "first" and "second" are not necessarily different. Meanwhile, in the embodiments of this application, the terms "exemplary" or "for example" are used to indicate that something is being used as an example, illustration, or description. Any embodiment or design scheme described as "exemplary" or "for example" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or design schemes. Specifically, the use of terms such as "exemplary" or "for example" is intended to present related concepts in a concrete manner for ease of understanding.

[0072] This application provides an optical communication device capable of converting photoelectric signals and transmitting optical signals. For example, it can be an optical module, which can be a long-range communication module, a short-range communication module, etc. Long-range communication modules include coherent communication modules, and short-range communication modules include banner communication modules. This application does not impose any special limitations on the specific form of the above-described optical communication device.

[0073] Optical communication equipment can be used in optical communication systems. For example, short-range communication modules can be used in data centers to collaboratively complete data exchange between servers at different levels within the data center. Figure 1 This is a schematic diagram of the structure of an optical communication system provided in an embodiment of this application.

[0074] like Figure 1As shown, in some embodiments, the optical communication system 1 includes an optical switch 100, which can be used for data exchange between servers at different levels in a large-scale data center, increasing bandwidth while significantly reducing the additional energy consumption caused by the routing of the switching network.

[0075] The optical switch 100 includes an optical module 200, a switch chip 130, and a fiber array unit (FAU) 120 for fixing the fiber array. In some embodiments, the optical module 200 may include a chip 110 and a circuit board as provided in this application embodiment, with the chip 110 disposed on the circuit board. The chip 110 and the fiber array can be plugged in via a connector. In some embodiments, the fiber array unit 120 includes an output fiber 121 for receiving optical signals output from the chip 110, and an input fiber 122 for inputting optical signals to the chip 110. The output fiber 121 and the input fiber 122 can be plugged into the chip 110 via different interfaces. The chip 110 in the optical module 200 is also connected to the switch chip 130. The switch chip 130 is used for processing and generating electrical signals.

[0076] To enable high-baud-rate communication scenarios with integrated transceiver capabilities, in some embodiments, chip 110 may include a modulator 112 and a photodetector 113. Conversion chip 130 may include an optical digital signal processing (oDSP) module 131, a driver module 132, and a trans-impedance amplifier (TIA) 133.

[0077] On one hand, the photodetector 113 can be connected to the input optical fiber 122. After receiving the optical signal from the input optical fiber 122, the photodetector 113 can generate a corresponding current signal based on the optical signal for processing. The transimpedance amplifier 133 is connected to the photodetector 113 and is used to amplify the current signal generated by the photodetector 113 to obtain a voltage signal. The oDSP module 131 can be connected to the transimpedance amplifier 133 and is used to control the transimpedance amplifier 133 to amplify the electrical signal and process the amplified electrical signal.

[0078] On the other hand, the oDSP module 131 is connected to the driver module 132 and is used to control the driver module 132 to generate a modulation signal. The driver module 132 is connected to the modulator 112 and is used to provide the modulation signal so that the modulator 112 can use the modulation signal to modulate the optical signal to be modulated, loading the modulation signal, which is an electrical signal, onto the optical signal to be modulated. The modulator 112 can be connected to the output optical fiber 121. After modulating the optical signal to be modulated, the modulator 112 can emit the modulated optical signal through the output optical fiber 121. The optical signal to be modulated can be provided by the light-emitting component 111.

[0079] The placement of the light-emitting component 111, which provides the optical signal to be modulated, determines the cost of the chip. For example, existing chips place the light-emitting component outside the chip, which increases the overall size of the device and causes high assembly complexity, thus increasing the cost of the chip.

[0080] To address this issue, this application provides a chip that integrates light-emitting components within the chip, thereby reducing the cost of chip-to-device packaging or module packaging. Figure 2 This is a schematic diagram of the structure of a chip provided in an embodiment of this application.

[0081] like Figure 2 As shown, the chip 110 includes: a substrate 10, an insulating layer 20, a light-emitting component 111, a second waveguide 30, a modulator 112, and a first coupler 40.

[0082] The substrate 10 may be made of at least one of the following materials: single-crystal silicon (Si), single-crystal germanium (Ge), gallium arsenide, indium phosphide, III-V compound semiconductor materials, II-VI compound semiconductor materials, or other semiconductor materials known in the art. Alternatively, it may be made of a non-conductive material such as glass, plastic, or sapphire wafer.

[0083] An insulating layer 20 is formed on the substrate 10. The insulating layer 20 may be made of silicon dioxide (SiO2).

[0084] To integrate the light-emitting component 111 into the chip 110, a groove 201 extending toward the substrate 10 is formed on the surface 20a of the insulating layer 20 facing away from the substrate 10. In one implementation, the groove 201 can be as follows: Figure 2 The through insulating layer 20 is shown to extend to the substrate 10. In another implementation, the groove 201 can also be as shown... Figure 4 The first position A extends to the insulating layer 20. At this time, along the direction perpendicular to the substrate 10, the height H3 of the insulating layer 20 is greater than the height H2 of the groove 201.

[0085] The light-emitting component 111 is disposed within the groove 201 and fixedly connected to the substrate 10. There are various ways to fix the light-emitting component 111 to the substrate 10, such as welding. In some embodiments, a welding point 70 is provided on the substrate, and a first electrode 111c corresponding to the welding point 70 is provided on the side of the light-emitting component 111 closest to the substrate 10. During the fixed connection, the first electrode 111c is welded to the welding point 70. It is understood that the height of the groove 201 along the direction perpendicular to the substrate 10 is related to the height of the welding point 70; the greater the height of the welding point 70, the smaller the height H2 of the groove 201 along the direction perpendicular to the substrate 10.

[0086] The light-emitting component 111 has a first waveguide 111a disposed therein. A second waveguide 30 is disposed within the groove 201. The first waveguide 111a and the second waveguide 30 of the light-emitting component 111 are coupled together. Figure 3 As shown, in one implementation, the coupling connection between the first waveguide 111a and the second waveguide 30 can be achieved through an overlapping coupling structure 1130. Alternatively, the orthographic projection of the first waveguide 111a onto the substrate 10 at least partially overlaps with the orthographic projection of the second waveguide 30 onto the substrate 10. The structures of the first waveguide 111a and the second waveguide 30 corresponding to the overlapping orthographic projections together form the coupling structure 1130. It is understood that the closer the distance between the first waveguide 111a and the second waveguide 30, the lower the coupling loss, achieving low loss in the chip 110 and improving its optical power.

[0087] In one implementation, such as Figure 3 As shown, the light-emitting component 111 can be a laser. The laser includes a substrate 1101, a grating 1102, an active region 1103, and a first waveguide 111a. The grating 1102 is formed on the substrate 1101. The active region 1103 is formed on the side of the grating 1102 facing away from the substrate 1101. Along a direction perpendicular to the substrate 10, the distance L1 between the substrate 1101 and the substrate 10 is greater than the distance L2 between the active region 1103 and the substrate 10. In this case, the laser can be fixed to the substrate 10 by flip-chip bonding, thereby simplifying the fabrication process and reducing costs. By bonding, the requirements for the flatness and smoothness of the surfaces of the light-emitting component 111 and the substrate 10 are lower, which reduces the difficulty of the manufacturing process and thus reduces costs.

[0088] And, such as Figure 2 As shown, the groove 201, in addition to providing mounting space for the light-emitting component 111, can also limit the setting position of the light-emitting component 111 to a certain extent, thus playing a positioning role. It is understood that the laser in the active region 1103 can enter the first waveguide 111a through coupling. The active region 1103 and the first waveguide 111a are made of different materials; the active region 1103 is made of group III-V materials.

[0089] To fix the laser in a specific position, in some embodiments, alignment marks 01 may be provided on both the laser and the insulating layer 20. The alignment marks 01 may be as follows: Figure 3 The alignment mark 01 is shown in a cross shape. This application does not limit the shape or number of alignment marks 01.

[0090] In some embodiments, a coupling stop structure is provided within the groove 201 to stop the laser after patching at a suitable position in a direction perpendicular to the substrate 10, thereby improving its yield. Figure 6a As shown, in one implementation, stop blocks 90 are arranged in an array on both sides of the second waveguide 30. The stop blocks 90 extend in a direction perpendicular to the substrate 10 to form a coupling stop structure. It is understood that the number of stop blocks 90 is not limited in this application.

[0091] In some embodiments, the second waveguide 30 includes a waveguide core and a cladding layer. The waveguide core is made of silicon nitride, and the cladding layer is made of oxide. Thinning the oxide layer facilitates low insertion loss evanescent wave coupling.

[0092] In order to place the second waveguide 30 within the groove 201, such as Figure 2 As shown, in one implementation, an insulating layer 20 is disposed within the groove 201, and the insulating layer 20 extends in a direction away from the substrate. Along a direction perpendicular to the substrate 10, the height H1 of the insulating layer 20 within the groove 201 is less than the height H2 of the groove 201. Along a direction parallel to the substrate 10, the width W1 of the insulating layer 20 within the groove 201 is less than the width W2 of the groove 201.

[0093] When both the light-emitting component 111 and the second waveguide 30 are disposed within the groove 201, a gap inevitably exists between the light-emitting component 111 and the second waveguide 30 because the light-emitting component 111 needs to be fixed to the substrate 10. In this embodiment, after the light-emitting component 111 is fixed, an adhesive layer is formed by filling the gap between the light-emitting component 111 and the second waveguide 30. This adhesive layer allows the air between the light-emitting component 111 and the second waveguide 30 to be expelled, thereby improving the coupling efficiency between the first waveguide 111a and the second waveguide 30 of the light-emitting component 111.

[0094] To reduce optical signal loss between the transmitting and receiving elements, it is combined with Figure 3 and Figure 6aIn one implementation, the second waveguide 30 is located between the light-emitting component 111 and the substrate 10 along a direction perpendicular to the substrate 10. Simultaneously, the extension direction of the first waveguide 111a is the same as the extension direction of the second waveguide 30, such that the orthographic projection of the first waveguide 111a onto the substrate 10 at least partially overlaps with the orthographic projection of the second waveguide 30 onto the substrate 10. Thus, the first waveguide 111a and the second waveguide 30 in the light-emitting component 111 are arranged vertically along a direction perpendicular to the substrate 10, achieving an overlapping coupling structure through projected overlap to realize evanescent wave coupling (EVL), achieving a low insertion loss and high tolerance coupling effect, thereby improving the yield of the chip 110. To adapt to more application scenarios, such as... Figure 6a and Figure 6b As shown, the laser employs a multi-ridge waveguide structure. When the multi-ridge waveguide is configured with multiple paths of the same wavelength, it satisfies DR (Digital Reduction) applications. Alternatively, when the multi-ridge waveguide is configured with different wavelengths, it satisfies FR (Flat Radiation Reduction) applications.

[0095] In addition, the multi-ridge waveguide of the laser can be designed as follows: Figure 6b The single-ended light output shown is designed to meet the requirements of the FR4 chip application. It can also be designed as follows: Figure 6a The dual-ended light output shown is designed to meet the application requirements of silicon photonics chips DR4 (400G), DR8 (800G), FR4, or 2*FR4. For the chip architecture of DR4 (400G), DR8 (800G), FR4, or FR4, please refer to the embodiments below.

[0096] To achieve selection of a specific wavelength, a phase shift is introduced into grating 1102. Grating 1102 may be a distributed feedback Bragg (DFB) grating, which introduces a phase shift in a uniformly distributed periodic refractive index grating region.

[0097] There are several options for the phase shift, including phase shift as... Or biphase shift, etc.

[0098] like Figure 6a As shown, in one implementation, electrode pairs 80 are disposed on both sides of the second waveguide 30. The electrode pairs 80 are used to generate a modulation electric field to modulate the optical signal in the second waveguide 30, thereby meeting the requirements of optical communication.

[0099] like Figure 5 As shown, in one implementation, along the extension direction of the first waveguide 111a, the second waveguide 30 includes a first end 301 facing away from the first waveguide 111a; from the first waveguide 111a to the first end 301, the width W3 of the second waveguide 30 first gradually increases and then gradually decreases. It is understood that the width of the second waveguide 30 is related to the coupling efficiency of the first waveguide 111a and the alignment tolerance requirements of the second waveguide 30.

[0100] like Figure 6a As shown, in one implementation, the width V1 of the first waveguide 111a gradually increases from the edge of the active region 1103 to the second end 111a1. The second end 111a1 is the end of the first waveguide 111a that faces away from the active region 1103. In some embodiments, when the width of the second waveguide 30 first gradually increases and then gradually decreases, the width of the portion of the first waveguide 111a coupled to it first gradually decreases and then gradually increases, to enhance the coupling connection.

[0101] like Figure 6a As shown, in one implementation, the light-emitting component 111 has a first cavity surface 111b perpendicular to the substrate 10, and the first cavity surface 111b is an arc surface. The arc surface can focus the light emitted by the light-emitting component 111, increasing the coupling efficiency with the second waveguide 30. In another implementation, the first cavity surface 111b can be a straight surface. The shape of the first cavity surface 111b is not limited in this application.

[0102] Please continue reading Figure 2 .

[0103] Both modulator 112 and first coupler 40 are formed within insulating layer 20. Modulator 112 is coupled to second waveguide 30. First coupler 40 is coupled to modulator 112. In one implementation, the chip may further include a third waveguide located within insulating layer 20, through which first coupler 40 is coupled to modulator 112. That is, both ends of the third waveguide are coupled to first coupler 40 and modulator 112, respectively. The third waveguide is made of silicon nitride (SiN). The silicon nitride-based third waveguide enables coupling between first coupler 40 and modulator 112 and offers the advantage of low insertion loss.

[0104] In this way, the optical signal provided by the light-emitting component 111 is transmitted to the modulator 112 through the second waveguide 30. The optical signal processed by the modulator 112 is then transmitted to the first coupler 40 to output the optical signal to the optical fiber. The first coupler 40 is an edge coupler.

[0105] To make the structure compact, in one implementation, a first coupler 40 is disposed between the modulator 112 and the light-emitting component 111 in a direction parallel to the substrate 10.

[0106] The following example, using the coupling connection between modulator 112 and second waveguide 30, illustrates a feasible implementation method for the coupling connection.

[0107] like Figure 7As shown, the second waveguide 30 includes a first portion 30a, and the modulator 112 includes a second portion 112a. The orthographic projections of the first portion 30a and the second portion 112a on the substrate coincide to form a coupling connection. It is understood that the modulator 112 and the second waveguide 30 are at a certain distance along a direction perpendicular to the substrate, and the gap formed by the modulator 112 and the second waveguide 30 can be filled with silicon dioxide. In one implementation, the second waveguide 30 can be L-shaped with a rounded corner (R) at the bend. It is understood that the bend of the second waveguide 30 can also be other low-loss bending transition structures, such as Euler curves or Bezier curves.

[0108] When the modulator 112 is made of silicon and the second waveguide 30 is made of silicon nitride, the coupling between the modulator 112 and the second waveguide 30 is silicon nitride-to-silicon coupling. Therefore, as... Figure 8 As shown, in one implementation, the optical signal in the second waveguide 30 can be transmitted first in the silicon waveguide 60, and then transmitted from the silicon waveguide 60 to the modulator 112.

[0109] In order to obtain a higher speed modulator, in one implementation, the modulator material includes lithium niobate (LiNbO3).

[0110] The first coupler 40 and the modulator 112 can be referred to in the way that the modulator 112 is coupled to the second waveguide 30, which will not be described in detail here.

[0111] In the above, the light-emitting component 111 is disposed in the groove 201 of the insulating layer 20 and is fixedly connected to the substrate 10, thereby realizing the integration of the light-emitting component 111, the second waveguide 30, and the modulator 112 and the first coupler 40 disposed in the insulating layer 20, which can adapt to multiple application scenarios while reducing costs.

[0112] With the development of optical communication, chips not only need to meet the requirements of low cost, but also high modulation rate, low loss, and low power consumption.

[0113] To minimize transmission loss in the chip, in some embodiments, the second waveguide 30 in the chip is a passive waveguide. Passive waveguides have low reflection loss, avoiding laser output jitter, mode hopping, or high noise.

[0114] In one implementation, the second waveguide 30 is made of silicon nitride (SiN). The use of silicon nitride in waveguides offers advantages such as low transmission loss, low reflection, temperature insensitivity, and high process tolerance, resulting in excellent performance of the second waveguide 30.

[0115] To enable the chip to meet the requirements of high baud rate light emission, in some embodiments, the modulator 112 is an active device exhibiting electro-optic effects. In one implementation, the modulator 112 is made of silicon (Si). Silicon enables the high-speed performance of the modulator 112 without the problem of lattice mismatch.

[0116] The chip provided in this application embodiment can simultaneously integrate silicon devices, silicon nitride devices, and light-emitting devices, forming a hybrid integration platform of silicon nitride (SiN)-silicon-on-insulator (SOI)-light-emitting device (multi-ridge waveguide surface-mount light source, such as a laser). Utilizing the low-loss characteristics of silicon nitride, passive waveguides and waveguide devices are formed, including widened waveguides, multiplexers (Muxes), demultiplexers (DeMuxes), polarization splitter rotators (PSRs), and multi-mode inferometers (MMIs). Various passive devices fabricated using silicon nitride have the advantages of temperature insensitivity and large process tolerance. The low-reflection characteristics of silicon nitride material better meet the requirements of on-chip integrated laser schemes for low chip reflection loss. Using on-chip silicon (Si) for doping to form modulator and resistor structures is highly beneficial for integration. On-chip detectors, including monitor photodetectors (PDs) and high-speed PDs, are realized using silicon (Si)-compatible germanium (Ge) materials. This combines the advantages of both silicon nitride (SiN) and silicon-on-insulator (SOI) platforms.

[0117] In some embodiments, in the optical waveguide switching region of SiN and Si, a Si-SiN overlapping coupling switching structure can be used to achieve the switching of light between the two waveguides.

[0118] Understandably, the mature gold-plated contact and interconnect technology of CMOS can be used to extract electrical signals.

[0119] In addition to the second waveguide 30, in one implementation, the first coupler 40 can also be a passive device with low loss, capable of transmitting higher quality optical signals to the output optical fiber. For example, the first coupler 40 may be made of silicon nitride to achieve low on-chip return loss.

[0120] In this way, different materials can meet the needs of different devices. Furthermore, the simultaneous inclusion of both passive and active components in the chip allows it to adapt to a wider range of scenarios, such as high-baud-rate communication with integrated transceivers. This facilitates network upgrades at a lower cost and with less energy consumption.

[0121] When a chip simultaneously incorporates a second waveguide formed of silicon nitride and a modulator formed of silicon, in order to reduce manufacturing complexity, such as... Figure 2 As shown, in one implementation, the second waveguide 30 is located on the side of the modulator 112 away from the substrate 10.

[0122] Combination Figures 9a to 9c Although integrating passive and active devices onto a single chip presents certain challenges, embodiments of this application provide a feasible example. For instance... Figure 9a As shown, a silicon-doped layer is formed on the side of the first insulating layer 21 away from the substrate 10, and this silicon-doped layer forms the modulator 112. Figure 9b As shown, a second insulating layer 22 is formed on the side of the modulator 112 opposite to the first insulating layer 21, such that the second insulating layer 22 completely covers the modulator 112. Figure 9c As shown, a silicon nitride layer is formed on the side of the second insulating layer 22 opposite to the first insulating layer 21, and this silicon nitride layer is used to form the second waveguide 30. It can be understood that the first insulating layer 21 and the second insulating layer 22 can be an integral structure without a boundary line.

[0123] To accomplish photoelectric detection functions, such as Figure 2 As shown, in addition to a substrate 10, an insulating layer 20, a light-emitting component 111, a second waveguide 30, a modulator 112, and a first coupler 40, the chip 110 also includes a photodetector 113 and a second coupler 50.

[0124] Both the photodetector 113 and the second coupler 50 are formed in the insulating layer 20, and are coupled together. The photodetector 113 is positioned between the modulator 112 and the second coupler 50 along a direction parallel to the substrate 10. Thus, the light signal input from the input optical fiber can be transmitted to the photodetector 113 through the second coupler 50, completing the photodetector operation. It is understood that the second coupler 50 can be an edge coupler, and its material may include silicon nitride.

[0125] The photodetector 113 may be made of germanium (Ge). Germanium enables high-speed detection, is compatible with complementary metal oxide semiconductor (CMOS) processes, supports large-scale production, and has a low-cost advantage.

[0126] To enable faster transmission of optical signals, such as Figure 2 As shown, in some embodiments, chip 110 further includes a heater 114. The heater 114 is disposed in the insulating layer 20 and is coupled to the modulator 112 and the first coupler 40, respectively.

[0127] In one implementation, a heater 114 is disposed between the modulator 112 and the first coupler 40 along a direction parallel to the substrate 10. The optical signal processed by the modulator 112 is transmitted to the first coupler 40 through the heater. The heater 114 can achieve temperature control of a specific area on the chip, thereby adjusting the refractive index of the waveguide through temperature changes, and thus changing the optical phase in the waveguide.

[0128] In some embodiments, such as Figure 2 As shown, a channel 10a is formed on the substrate 10 opposite to the heater 114 to achieve heat preservation. In this way, by utilizing the low heat transfer efficiency of air, the transfer of heat to the substrate 10 can be slowed down, so that the temperature of the heating zone corresponding to the heater 114 is higher, thereby improving the heating efficiency of the heater 114 and reducing power consumption.

[0129] Based on the silicon nitride (SiN)-silicon on insulator (SOI)-light-emitting device (multi-ridge waveguide surface-mount light source, such as laser) hybrid integration platform given in the above embodiments of this application, the embodiments of this application provide four different chip structures based on this platform, namely silicon photonic chip DR4 (400G), silicon photonic chip DR8 (800G), chip FR4 and chip FR4.

[0130] The following explanations are provided in conjunction with the accompanying drawings.

[0131] Figure 10 An optical path diagram of a silicon photonics chip DR4 (400G) provided for an embodiment of this application. For example... Figure 10 The image shows the optical path diagram of the DR4 chip integrating a single laser. It employs a single laser with a dual-ridge design (see [link]). Figure 6a or Figure 6b Single-ended light output (see) Figure 6b ) or dual-ended light output (see Figure 6a The laser beam is transmitted through a silicon nitride waveguide (the second waveguide in the aforementioned embodiment) to four silicon modulators. The modulated light then travels through the silicon nitride waveguide (the third waveguide in the aforementioned embodiment) to the edge of the chip, and is then output to the outside of the chip via a silicon nitride edge coupler (EC) (the first coupler in the aforementioned embodiment). The silicon nitride waveguide can incorporate a heater, beam splitter, and monitor photo detector (PD) structure to monitor and lock the operating point. At the receiving end, the four beams entering the chip from the edge coupler (the second coupler in the aforementioned embodiment) are transmitted through the silicon nitride waveguide to four photodetectors (PDs) for photoelectric detection.

[0132] Figure 11 An optical path diagram of a silicon photonics chip DR8 (800G) provided for an embodiment of this application. For example... Figure 11 The diagram shows the optical path of the DR8 chip, which integrates a single laser. It employs either a single-laser, four-ridge, single-end output scheme or a dual-laser, dual-ridge (WL1 and WL2) single-end output scheme. Different wavelengths of light from the laser are transmitted through silicon nitride waveguides to four silicon modulators. The light modulated by the silicon modulators is combined by a multiplexer (Mux) structure made of silicon nitride waveguides, then transmitted through the silicon nitride waveguides to the chip edge, and finally output outside the chip by silicon nitride edge couplers. Heaters, beam splitters, and monitoring PD structures can be used in the silicon nitride waveguides to monitor and lock the operating point. At the receiving end, one beam of light entering the chip from the edge coupler is demultiplexed by a deMux structure, then transmitted through the waveguide to four photodetectors for photoelectric detection.

[0133] Figure 12 An optical path diagram of a chip FR4 provided for an embodiment of this application. For example... Figure 12 The diagram shows the optical path of the FR4 chip with integrated dual lasers. It employs either a single-laser, four-ridge, single-end output scheme or a dual-laser, two-ridge (WL1 and WL2, and WL3 and WL4) single-end output scheme. Different wavelengths of light from the lasers are transmitted through silicon nitride waveguides to four silicon modulators. The light modulated by the silicon modulators is combined by a Mux structure made of silicon nitride waveguides, then transmitted through the silicon nitride waveguides to the chip edge, and finally output outside the chip by silicon nitride edge couplers. Heaters, beam splitters, and monitoring PD structures can be used in the silicon nitride waveguides to monitor and lock the operating point. At the receiving end, one beam entering the chip from the edge coupler undergoes wavelength splitting through a DeMux structure, then is transmitted through the waveguide to four photodetectors for photoelectric detection.

[0134] Figure 13 An optical path diagram of a 2*chip FR4 provided for an embodiment of this application. For example... Figure 13The diagram shows the optical path of a 2*FR4 chip integrating dual lasers. It employs either a single-laser, four-ridge, dual-end output scheme or a dual-laser, dual-ridge (WL1 and WL2, and WL3 and WL4) dual-end output scheme. Different wavelengths of light from the lasers are transmitted through silicon nitride waveguides to eight silicon modulators. The light modulated by the silicon modulators is combined by a Mux structure made of silicon nitride waveguides, then transmitted through silicon nitride waveguides to the chip edge, and finally output outside the chip by silicon nitride edge couplers. Heaters, beam splitters, and monitoring PD structures can be used in the waveguides to monitor and lock the operating point. At the receiving end, the two beams entering the chip from the edge couplers undergo wavelength splitting through a DeMux structure, and then are transmitted through waveguides to eight photodetectors for photoelectric detection.

[0135] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A chip, characterized in that, The device includes a substrate, an insulating layer, a light-emitting component, a modulator, and a first coupler. The insulating layer is formed on the substrate, and a groove extending toward the substrate is formed on the surface of the insulating layer away from the substrate. The light-emitting component is disposed in the groove and is fixedly connected to the substrate. A first waveguide is disposed in the light-emitting component, and a second waveguide is located in the insulating layer within the groove. The first waveguide and the second waveguide are coupled together. Both the modulator and the first coupler are formed in the insulating layer, and the modulator is coupled to the second waveguide and the first coupler, respectively; wherein: The light-emitting component includes multiple active regions, which are arranged at intervals, and at least a portion of the light emitted by each active region is coupled to the first waveguide. The light-emitting component includes a first electrode, and the substrate includes a soldering point. The first electrode is soldered to the soldering point, which is located at the bottom of the groove. The first electrode is located on the side of the light-emitting component facing the second waveguide. The insulating layer at the bottom of the groove protrudes in a direction away from the substrate. The height of the insulating layer in the groove is less than the height of the groove. The second waveguide is located within the insulating layer in the groove.

2. The chip according to claim 1, characterized in that, The light-emitting component emits light from both ends.

3. The chip according to claim 1 or 2, characterized in that, When the first electrode is welded to the welding point, the height of the first electrode is greater than the height of the insulating layer in the groove.

4. The chip according to any one of claims 1-3, characterized in that, When the first electrode is welded to the welding point, a gap is left between the light-emitting component and the second waveguide.

5. The chip according to any one of claims 1-4, characterized in that, Along a direction perpendicular to the substrate, the second waveguide is located between the light-emitting component and the substrate; The first waveguide extends in the same direction as the second waveguide; the orthographic projection of the first waveguide onto the substrate at least partially overlaps with the orthographic projection of the second waveguide onto the substrate.

6. The chip according to any one of claims 1-5, characterized in that, Along the extension direction of the first waveguide, the second waveguide includes a first end opposite to the first waveguide; from the first waveguide to the first end, the width of the second waveguide first gradually increases and then gradually decreases.

7. The chip according to any one of claims 1-6, characterized in that, The light-emitting component has a first cavity surface perpendicular to the substrate, and the first cavity surface is an arc surface.

8. The chip according to any one of claims 1-7, characterized in that, Along a direction parallel to the substrate, the first coupler is disposed between the modulator and the light-emitting component.

9. The chip according to any one of claims 1-8, characterized in that, The second waveguide is located on the side of the modulator away from the substrate.

10. The chip according to any one of claims 1-9, characterized in that, The chip also includes: a photodetector and a second coupler; Both the photodetector and the second coupler are formed in the insulating layer, and the photodetector and the second coupler are coupled together.

11. The chip according to any one of claims 1-10, characterized in that, The second waveguide is a passive waveguide.

12. The chip according to claim 11, characterized in that, The second waveguide is made of silicon nitride.

13. The chip according to any one of claims 1-12, characterized in that, The first coupler is a passive device, and the modulator is an active device.

14. The chip according to claim 13, characterized in that, The first coupler is made of silicon nitride; the modulator is made of silicon.

15. The chip according to any one of claims 1-14, characterized in that, The chip further includes a heater; the heater is disposed within the insulating layer, and the heater is coupled to the modulator and the first coupler respectively.

16. The chip according to any one of claims 1-15, characterized in that, The chip also includes: The third waveguide is located within the insulating layer, and the first coupler is coupled to the modulator through the third waveguide; the material of the third waveguide includes silicon nitride.

17. The chip according to any one of claims 1-16, characterized in that, The light-emitting component includes a laser, which includes: a substrate, a grating, and an active region; The grating is formed on the substrate; the active region is formed on the side of the grating facing away from the substrate; the first waveguide includes the active region; the active region and the first waveguide are coupled together. Along a direction perpendicular to the substrate, the distance between the substrate and the base is greater than the distance between the active region and the substrate.

18. The chip according to claim 17, characterized in that, The grating is provided with a phase shift, the phase shift being... Or a biphase shift.

19. An optical communication device, characterized in that, include: The chip as described in any one of claims 1-18; A circuit board, on which the chip is mounted.

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