阅读说明：本技术 一种激光器组件及光模块 (Laser assembly and optical module ) 是由 陈骁 赵昀松 李静思 刘志程 李召松 于 2021-08-16 设计创作，主要内容包括：本申请提供的激光器组件及光模块,包括：双激光器芯片,为包括两个发光单元的双激光器结构,顶面设置第一正极和第二正极以及底面设置负极,两个发光单元产生的光信号进行叠加；基板,表面设置有第一高速信号线、第二高速信号线和第一回流地；第一正极电连接第一高速信号线,第二正极电连接第二高速信号线,所述负极电连接所述第一回流地,所述第一高速信号线和所述第二高速信号线使所述第一正极和所述第二正极接收到信号具有预设时延差。本申请提供的激光器组件及光模块,利用基板向激光器芯片注入具有时延差的高速信号,然后利用高速信号注入的时延差,实现激光器芯片的S21带宽曲线在更高频位置的补偿,以进一步提升3dB带宽和传输速率。(The application provides laser instrument subassembly and optical module includes: the dual-laser chip is of a dual-laser structure comprising two light-emitting units, a first positive electrode and a second positive electrode are arranged on the top surface, a negative electrode is arranged on the bottom surface, and optical signals generated by the two light-emitting units are superposed; a substrate, a surface of which is provided with a first high-speed signal line, a second high-speed signal line and a first return ground; the first positive electrode is electrically connected with the first high-speed signal line, the second positive electrode is electrically connected with the second high-speed signal line, the negative electrode is electrically connected with the first return ground, and the first high-speed signal line and the second high-speed signal line enable the first positive electrode and the second positive electrode to have preset time delay difference when receiving signals. According to the laser assembly and the optical module, the substrate is used for injecting a high-speed signal with time delay difference into the laser chip, and then the time delay difference of the high-speed signal injection is used for realizing the compensation of an S21 bandwidth curve of the laser chip at a higher frequency position, so that the 3dB bandwidth and the transmission rate are further improved.)

1. A laser assembly, comprising:

the dual-laser chip is of a dual-laser structure comprising two light-emitting units, a first positive electrode and a second positive electrode are arranged on the top surface of the dual-laser chip, a negative electrode is arranged on the bottom surface of the dual-laser chip, and high-speed signals with preset time delay difference are injected into the first positive electrode and the second positive electrode to enable optical signals generated by the two light-emitting units to be superposed;

a substrate on which a first high-speed signal line, a second high-speed signal line and a first return ground are disposed;

wherein: the first positive electrode is electrically connected with the first high-speed signal wire, the second positive electrode is electrically connected with the second high-speed signal wire, the negative electrode is electrically connected with the first return ground, and the first high-speed signal wire and the second high-speed signal wire have different lengths, so that high-frequency signals transmitted to the first positive electrode and the second positive electrode through the first high-speed signal wire and the second high-speed signal wire have preset time delay differences.

2. The laser assembly of claim 1, wherein the first positive wire is connected to the first high speed signal line, and the second positive wire is connected to the second high speed signal line;

the negative electrode is connected with the first reflow ground by welding.

3. The laser assembly of claim 1, wherein the first positive electrode is flip-chip bonded to the first high speed signal line and the second positive electrode is flip-chip bonded to the second high speed signal line; the negative electrode is connected with the first reflux ground through a routing.

4. The laser assembly of claim 1, wherein the twin laser chip comprises a ridge waveguide, and the first and second anodes are electrically connected to different positions of the ridge waveguide, respectively, such that the twin laser chip forms a twin laser structure comprising two light emitting units;

the substrate is a ceramic substrate, a glass substrate, a silicon substrate or an organic plate substrate.

5. The laser assembly of claim 1, further comprising a first matching resistor disposed in series on the first high speed signal line proximate and electrically connecting the first anode and a second matching resistor disposed in series on the second high speed signal line proximate and electrically connecting the second anode.

6. The laser module as claimed in claim 1, wherein the first positive electrode is closer to a light emitting end of the twin laser chip than the second positive electrode, the first high speed signal line is a straight high speed signal line, and the second high speed signal line is a bent high speed signal line.

7. The laser assembly of claim 5, wherein the first and second matching resistors are each thin film resistors.

8. The laser assembly of claim 6, wherein an end of the first high speed signal line distal from the twin laser chip is parallel to an end of the second high speed signal line distal from the twin laser chip;

the dual laser chip is disposed at one end of the substrate, and the first high-speed signal line extends from one end of the substrate to the other end of the substrate.

9. The laser assembly of claim 1, wherein the first reflow ground is disposed around the first high speed signal line and the second high speed signal line;

and a second reflow ground is arranged on the bottom surface of the substrate, and a via hole is arranged on the substrate and is connected with the first reflow ground and the second reflow ground.

10. A light module comprising a laser assembly and a laser driver, the laser assembly being the laser assembly of claim 1;

the laser driver transmits a high-frequency signal to a double-laser chip in the laser assembly through a first high-speed signal line and a second high-speed signal line on a substrate in the laser assembly, and the high-frequency signal output by the laser driver generates a preset time delay difference through the first high-speed signal line and the second high-speed signal line.

Technical Field

The application relates to the technical field of optical fiber communication, in particular to a laser assembly and an optical module.

Background

With the development of new services and application modes such as cloud computing, mobile internet, video and the like, the development and progress of the optical communication technology become increasingly important. In the optical communication technology, an optical module is a tool for realizing the interconversion of optical signals and is one of key devices in optical communication equipment, and the transmission rate of the optical module is continuously increased along with the development requirement of the optical communication technology.

Typically, the core device in the optical module comprises a semiconductor laser chip. The semiconductor laser chip is a device which generates laser by using a semiconductor material as a working substance, realizes the population inversion of non-equilibrium carriers between energy bands (a conduction band and a valence band) of the semiconductor substance or between the energy bands of the semiconductor substance and an impurity (an acceptor or a donor) energy level through a certain excitation mode, and generates a stimulated emission effect when a large number of electrons in a population inversion state are compounded with holes, thereby generating laser.

In order to meet the continuously increasing bandwidth demand, optoelectronic devices are continuously updated and iterated, such as DFB (distributed feedback laser) semiconductor lasers, which belong to edge-emitting lasers. The high-frequency modulation performance of the DFB semiconductor laser is determined by an active region (intrinsic laser), the DFB semiconductor laser with the speed of 25Gbps is developed and produced in mass production at present, the design principle is that high-quality modulation electrical signals with the speed of 25Gbps are injected into the laser, electric and optical oscillation effects are formed in the active region inside a laser chip, and modulation laser with the speed of 25Gbps is formed through stimulated emission. However, the design requirement for higher speed is severely restricted by the material differential gain and the carrier lifetime, so that the conventional DFB semiconductor laser cannot meet the requirement at present.

Disclosure of Invention

The embodiment of the application provides a laser assembly and an optical module, which ensure that the bandwidth of a DFB laser chip reaches a higher speed level.

In a first aspect, the present application provides a laser module, comprising:

the dual-laser chip is of a dual-laser structure comprising two light-emitting units, a first positive electrode and a second positive electrode are arranged on the top surface of the dual-laser chip, a negative electrode is arranged on the bottom surface of the dual-laser chip, and high-speed signals with preset time delay difference are injected into the first positive electrode and the second positive electrode to enable optical signals generated by the two light-emitting units to be superposed;

a substrate on which a first high-speed signal line, a second high-speed signal line and a first return ground are disposed;

wherein: the first positive electrode is electrically connected with the first high-speed signal wire, the second positive electrode is electrically connected with the second high-speed signal wire, the negative electrode is electrically connected with the first return ground, and the first high-speed signal wire and the second high-speed signal wire have different lengths, so that high-frequency signals transmitted to the first positive electrode and the second positive electrode through the first high-speed signal wire and the second high-speed signal wire have preset time delay differences.

In a second aspect, the present application provides an optical module, including a laser module and a laser driver, where the laser module is the laser module according to the first aspect;

the laser driver transmits a high-frequency signal to a double-laser chip in the laser assembly through a first high-speed signal line and a second high-speed signal line on a substrate in the laser assembly, and the high-frequency signal output by the laser driver generates a preset time delay difference through the first high-speed signal line and the second high-speed signal line.

In the laser assembly and the optical module provided by the application, the laser assembly comprises a double laser chip and a substrate; the dual laser chip is of a dual laser structure comprising two light emitting units, and a first anode and a second anode which are used for injecting high-speed signals with preset time delay difference are arranged on the top surface of the dual laser chip; the first high-speed signal line and the second high-speed signal line are arranged on the substrate and have different lengths, the first positive pole and the second positive pole of the double-laser chip are correspondingly connected with the first high-speed signal line and the second high-speed signal line, and then the high-frequency signal injected into the double-laser chip generates preset time delay difference through the first high-speed signal line and the second high-speed signal line. Therefore, the high-frequency signal to be injected into the double laser chip has preset time delay difference when being injected into the double laser chip by passing through the first high-speed signal wire and the second high-speed signal wire, the high-frequency signal with the preset time delay difference is injected into the light-emitting unit of the double laser chip, electric and light oscillation action is formed in respective resonant cavities firstly, then light and light oscillation effect is carried out, the high-speed modulation light generated by the double laser structure has specific phase difference for superposition by utilizing the time delay difference of the high-speed signal injection, and further a single laser 3dB bandwidth curve has a flattening effect at a higher frequency position, so that compensation of an S21 bandwidth curve of the laser chip at a higher frequency position is realized, the 3dB bandwidth and the transmission rate are further improved, and modulation at a higher rate is achieved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a schematic diagram of a connection relationship of an optical communication terminal;

FIG. 2 is a schematic diagram of an optical network unit;

fig. 3 is a schematic structural diagram of an optical module according to an embodiment of the present disclosure;

FIG. 4 is a schematic diagram of an exploded structure of an optical module according to an embodiment of the present application;

fig. 5 is a schematic diagram of an tosa according to an embodiment of the present disclosure;

fig. 6 is an exploded view of an tosa according to an embodiment of the present disclosure;

fig. 7 is a schematic structural diagram of a twin laser chip according to an embodiment of the present disclosure;

fig. 8 is a schematic top view of a laser module according to an embodiment of the present disclosure;

fig. 9 is a schematic bottom view of a laser module according to an embodiment of the present disclosure;

FIG. 10 is a schematic top view of another laser module according to an embodiment of the present disclosure;

fig. 11 is a schematic bottom structure diagram of another laser module according to an embodiment of the present disclosure.

Detailed Description

In order to facilitate the technical solution of the present application, some concepts related to the present application will be described below.

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

One of the core links of optical fiber communication is the interconversion of optical and electrical signals. The optical fiber communication uses optical signals carrying information to transmit in information transmission equipment such as optical fibers/optical waveguides, and the information transmission with low cost and low loss can be realized by using the passive transmission characteristic of light in the optical fibers/optical waveguides; meanwhile, the information processing device such as a computer uses an electric signal, and in order to establish information connection between the information transmission device such as an optical fiber or an optical waveguide and the information processing device such as a computer, it is necessary to perform interconversion between the electric signal and the optical signal.

The optical module realizes the function of interconversion of optical signals and electrical signals in the technical field of optical fiber communication, and the interconversion of the optical signals and the electrical signals is the core function of the optical module. The optical module is electrically connected with an external upper computer through a golden finger on an internal circuit board of the optical module, and the main electrical connection comprises power supply, I2C signals, data signals, grounding and the like; the electrical connection mode realized by the gold finger has become the mainstream connection mode of the optical module industry, and on the basis of the mainstream connection mode, the definition of the pin on the gold finger forms various industry protocols/specifications.

Fig. 1 is a schematic diagram of connection relationship of an optical communication terminal. As shown in fig. 1, the connection of the optical communication terminal mainly includes the interconnection among the optical network terminal 100, the optical module 200, the optical fiber 101 and the network cable 103;

one end of the optical fiber 101 is connected with a far-end server, one end of the network cable 103 is connected with local information processing equipment, and the connection between the local information processing equipment and the far-end server is completed by the connection between the optical fiber 101 and the network cable 103; and the connection between the optical fiber 101 and the network cable 103 is made by the optical network terminal 100 having the optical module 200.

An optical port of the optical module 200 is externally accessed to the optical fiber 101, and establishes bidirectional optical signal connection with the optical fiber 101; an electrical port of the optical module 200 is externally connected to the optical network terminal 100, and establishes bidirectional electrical signal connection with the optical network terminal 100; the optical module realizes the interconversion of optical signals and electric signals, thereby realizing the establishment of information connection between the optical fiber and the optical network terminal; specifically, the optical signal from the optical fiber is converted into an electrical signal by the optical module and then input to the optical network terminal 100, and the electrical signal from the optical network terminal 100 is converted into an optical signal by the optical module and input to the optical fiber.

The optical network terminal is provided with an optical module interface 102, which is used for accessing an optical module 200 and establishing bidirectional electric signal connection with the optical module 200; the optical network terminal is provided with a network cable interface 104, which is used for accessing the network cable 103 and establishing bidirectional electric signal connection with the network cable 103; the optical module 200 is connected to the network cable 103 through the optical network terminal 100, specifically, the optical network terminal transmits a signal from the optical module to the network cable and transmits the signal from the network cable to the optical module, and the optical network terminal serves as an upper computer of the optical module to monitor the operation of the optical module.

At this point, a bidirectional signal transmission channel is established between the remote server and the local information processing device through the optical fiber, the optical module, the optical network terminal and the network cable.

Common information processing apparatuses include routers, switches, electronic computers, and the like; the optical network terminal is an upper computer of the optical module, provides data signals for the optical module, and receives the data signals from the optical module, and the common upper computer of the optical module also comprises an optical line terminal and the like.

Fig. 2 is a schematic diagram of an optical network terminal structure. As shown in fig. 2, the optical network terminal 100 has a circuit board 105, and a cage 106 is disposed on a surface of the circuit board 105; an electric connector is arranged in the cage 106 and used for connecting an electric port of an optical module such as a golden finger; the cage 106 is provided with a heat sink 107, and the heat sink 107 has a projection such as a fin that increases a heat radiation area.

The optical module 200 is inserted into the optical network terminal, specifically, the electrical port of the optical module is inserted into the electrical connector inside the cage 106, and the optical port of the optical module is connected to the optical fiber 101.

The cage 106 is positioned on the circuit board, and the electrical connector on the circuit board is wrapped in the cage, so that the electrical connector is arranged in the cage; the optical module is inserted into the cage, held by the cage, and the heat generated by the optical module is conducted to the cage 106 and then diffused by the heat sink 107 on the cage.

The fifth generation mobile communication technology (5G) currently meets the current growing demand for high-speed wireless transmission. The frequency spectrum adopted by the 5G communication is much higher than that adopted by the 4G communication, which brings a greatly improved communication rate for the 5G communication, but the transmission attenuation of the signal is relatively obviously increased.

The new service characteristics and higher index requirements of 5G provide new challenges for the bearer network architecture and each layer of technical solutions, wherein the optical module serving as a basic constituent unit of the physical layer of the 5G network also faces technical innovation and upgrade, which is mainly reflected in that the optical module applied to 5G transmission needs to have two basic technical characteristics of high-speed transmission and low return loss. In order to meet the requirement of an optical module in a 5G communication network, an embodiment of the present application provides an optical module. Fig. 3 is a schematic view of an optical module according to an embodiment of the present disclosure, and fig. 4 is a schematic view of an exploded structure of an optical module according to an embodiment of the present disclosure. As shown in fig. 3 and 4, an optical module 200 provided in the embodiment of the present application includes an upper housing 201, a lower housing 202, a circuit board 203, a circular-square tube 300, a transmitter-receiver sub-module 400, and a receiver sub-module 500.

The upper shell 201 is covered on the lower shell 202 to form a wrapping cavity with two openings; the outer contour of the wrapping cavity is generally a square body, and specifically, the lower shell comprises a main plate and two side plates which are positioned at two sides of the main plate and are perpendicular to the main plate; the upper shell comprises a cover plate, and the cover plate covers two side plates of the upper shell to form a wrapping cavity; the upper shell can also comprise two side walls which are positioned at two sides of the cover plate and are perpendicular to the cover plate, and the two side walls are combined with the two side plates to realize that the upper shell covers the lower shell.

The two openings may be two ends (204, 205) in the same direction, or two openings in different directions; one opening is an electric port 204, and a gold finger of the circuit board extends out of the electric port 204 and is inserted into an upper computer such as an optical network terminal; the other opening is an optical port 205 for external optical fiber access; the photoelectric devices such as the circuit board 203, the round and square tube 300, the transmitter sub-module 400 and the receiver sub-module 500 are located in the package cavity formed by the upper and lower shells.

The assembly mode of combining the upper shell 201 and the lower shell 202 is adopted, so that the round square tube body 300, the transmitter optical subassembly 400, the receiver optical subassembly 500 and other devices can be conveniently installed in the shells, and the upper shell 201 and the lower shell 202 form an outermost packaging protection shell of the optical module; the upper shell 201 and the lower shell 202 are generally made of metal materials, which is beneficial to realizing electromagnetic shielding and heat dissipation; generally, the housing of the optical module is not made into an integrated component, so that when devices such as a circuit board and the like are assembled, the positioning component, the heat dissipation component and the electromagnetic shielding component cannot be installed, and the production automation is not facilitated.

Typically, the optical module 200 further includes an unlocking component located on an outer wall of the package cavity/lower housing 202 for implementing a fixed connection between the optical module and the upper computer or releasing the fixed connection between the optical module and the upper computer.

The unlocking component is provided with a clamping component matched with the upper computer cage; the end of the unlocking component can be pulled to enable the unlocking component to move relatively on the surface of the outer wall; the optical module is inserted into a cage of the upper computer, and the optical module is fixed in the cage of the upper computer by a clamping component of the unlocking component; by pulling the unlocking component, the clamping component of the unlocking component moves along with the unlocking component, so that the connection relation between the clamping component and the upper computer is changed, the clamping relation between the optical module and the upper computer is released, and the optical module can be drawn out from the cage of the upper computer.

The circuit board 203 is provided with circuit traces, electronic components (such as capacitors, resistors, triodes, and MOS transistors), and chips (such as an MCU, a clock data recovery CDR, a power management chip, and a data processing chip DSP).

The circuit board 203 connects the electrical appliances in the optical module together according to the circuit design through circuit wiring to realize the electrical functions of power supply, electrical signal transmission, grounding and the like.

The circuit board 203 is generally a rigid circuit board, which can also realize a bearing effect due to its relatively hard material, for example, the rigid circuit board can stably bear a chip; when the optical transceiver is positioned on the circuit board, the rigid circuit board can also provide stable bearing; the hard circuit board can also be inserted into an electric connector in the upper computer cage, and specifically, a metal pin/golden finger is formed on the surface of the tail end of one side of the hard circuit board and is used for being connected with the electric connector; these are not easily implemented with flexible circuit boards.

A flexible circuit board is also used in a part of the optical module to supplement a rigid circuit board; the flexible circuit board is generally used in combination with a rigid circuit board, for example, the rigid circuit board may be connected to the optical transceiver device through the flexible circuit board.

As shown in fig. 4, in the optical module provided in this embodiment, the tosa 400 and the rosa 500 are both disposed on the circular-square tube 300, the tosa 400 is used for outputting signal light, and the rosa 500 is used for receiving signal light from outside the optical module. The round and square tube 300 is provided with an optical fiber adapter for connecting an external optical fiber, and the round and square tube 300 is usually provided with a lens assembly for changing the propagation direction of the signal light output by the tosa 400 or the signal light input by the external optical fiber. The tosas 400 and 500 are physically separated from the circuit board 203, so that it is difficult to directly connect the tosas 400 and 500 to the circuit board 203, and therefore the tosas 400 and 500 are electrically connected by flexible circuit boards.

As shown in fig. 4, the optical module 200 provided in the embodiment of the present application includes a circuit board 203, a circular-square tube 300, and a tosa 400, and the tosa 400 is connected to the circuit board 203 through a flexible circuit board. The tosa 400 is disposed on the round-square tube 300 and is coaxial with the fiber adapter of the round-square tube 300, but the tosa 400 may not be coaxial with the fiber adapter in the embodiment. In addition, the internal structure of the optical module shown in fig. 3 and fig. 4 is only an example provided in the embodiment of the present application, and the internal structure of the optical module provided in the embodiment of the present application may also be in other structural forms, for example, the tosa 400 may also adopt a COB package structure, a BOX structure, and the like.

Fig. 5 is a schematic diagram of an tosa according to an embodiment of the present disclosure. Fig. 6 is an exploded schematic view of an tosa according to an embodiment of the present disclosure. As shown in fig. 5 and 6, in some embodiments of the present application, the tosa 400 includes a socket 410, a cap 420, and other devices disposed in the cap 420 and the socket 410, the cap 420 is covered at one end of the socket 410, the socket 410 includes a plurality of pins for electrically connecting the flexible circuit board to other electrical devices in the tosa 400, and thus electrically connecting the tosa 400 to the circuit board 203; a laser module 600, a lens, and the like are provided in the stem 410, and the laser module 600 is used to generate laser light.

The laser module 600 provided in the embodiment of the present application includes a laser chip, and the laser chip is configured to generate laser according to a received high-speed signal, such as a dfb (distributed feedback semiconductor laser) laser chip. In order to solve the problem that the DFB semiconductor laser cannot meet the requirement of higher speed due to the serious restriction of material differential gain and carrier service life, two anodes are arranged on the top surface of a laser chip in the embodiment of the application, the two anodes are respectively and electrically connected with a ridge waveguide to form a double-laser structure, and then two paths of high-frequency signals with time delay difference are correspondingly received through the two anodes, so that the compensation of an S21 bandwidth curve of the laser chip at a higher-frequency position is realized, the 3dB bandwidth and the transmission rate are further improved, and the modulation of higher speed is achieved.

In this embodiment, the laser module 600 includes a dual laser chip, the dual laser chip includes two light emitting units, and when the high-speed signals injected by the two light emitting units have a predetermined time delay difference, the light signals generated by the light emitting units can be superimposed. Alternatively, the twin laser chip may adopt a twin laser co-waveguide structure.

Fig. 7 is a schematic structural diagram of a twin laser chip according to an embodiment of the present disclosure. As shown in fig. 7, a laser module 600 provided in the embodiment of the present application includes a twin laser chip 610, where the twin laser chip 610 includes a ridge waveguide 611, a first positive electrode 612 and a second positive electrode 613 disposed on a top surface of the twin laser chip 610, and a negative electrode 614 disposed on a bottom surface of the twin laser chip 610; the first positive electrode 612 and the second positive electrode 613 are electrically connected to the ridge waveguide 611, and a high-frequency electric signal can be injected into the ridge waveguide 611 through the first positive electrode 612 and the second positive electrode 613. In some embodiments of the present application, when a high frequency electric signal is injected into the ridge waveguide 611 through the first and second anodes 612 and 613, high-speed modulated light generated by the single laser in the twin laser structure is emitted through the end surface of the upper portion of the ridge waveguide 611 in the direction shown in fig. 7, as indicated by the arrow in fig. 7.

In the embodiment of the present application, two high-speed electrical signals with a predetermined delay difference are injected into the ridge waveguide 611 through the first positive electrode 612 and the second positive electrode 613. Optionally, the lengths of the RF traces for injecting the two high-speed signals are adjusted to make the two paths have a predetermined delay difference. However, since the twin laser chip 610 is small in area, there is not enough room to reroute the two-way RF traces.

In order to meet the requirement of injecting two paths of high-speed electrical signals with a preset time delay difference into the twin laser chip 610, in the embodiment of the present application, the laser module 600 further includes a substrate, on which a first high-speed signal line, a second high-speed signal line, and a first return ground are disposed; the first positive electrode 612 is electrically connected to the first high-speed signal line, the second positive electrode 613 is electrically connected to the second high-speed signal line, and the negative electrode 614 is electrically connected to the first return ground; the first high-speed signal line and the second high-speed signal line are combined to inject two high-speed electric signals with preset time delay difference into the twin laser chip 610. In the embodiment of the present application, the first high-speed signal line and the second high-speed signal line are located and oriented according to the size of the substrate and the requirement of the dual laser chip 610. Optionally, the length of the second high-speed signal line is greater than the length of the first high-speed signal line or the length of the first high-speed signal line is greater than the length of the second high-speed signal line to generate a predetermined delay difference. In the embodiment of the application, the preset time delay difference can be obtained by combining three-dimensional electromagnetic field simulation with a laser rate equation and laser active region design comprehensive calculation.

In the embodiment of the present application, the substrate may be a ceramic substrate, a glass substrate, a silicon substrate, an organic plate substrate, or the like. Alternatively, the first high-speed signal line, the second high-speed signal line, and the first reflow are disposed on a surface of the substrate.

In some embodiments of the present application, the first positive electrode 612 and the second positive electrode 613 of the dual laser chip 610 are correspondingly connected to the first high-speed signal line and the second high-speed signal line by wire bonding, that is, the first positive electrode 612 and the second positive electrode 613 are correspondingly connected to the first high-speed signal line and the second high-speed signal line by gold wire bonding, and the negative electrode 614 of the dual laser chip 610 is soldered to the first reflow ground.

In some embodiments of the present application, the first positive electrode 612 and the second positive electrode 613 of the dual laser chip 610 are flip-chip bonded to the first high speed signal line and the second high speed signal line, and the negative electrode 614 of the dual laser chip 610 is connected to the first reflow ground by wire bonding, i.e., the negative electrode 614 is connected to the first reflow ground by gold wire bonding. Optionally, the cathode 614 of the twin laser chip 610 is connected to the first reflow ground by a plurality of gold wire bonds.

In some embodiments of the present application, in order to reasonably utilize the space on the substrate and the arrangement of the high speed signal lines, the dual laser chip 610 is disposed near the end of the substrate, i.e., one end of the first and second high speed signal lines is disposed near the end of the substrate for electrically connecting the first anode 612 and the second anode 613, and the other end of the first and second high speed signal lines is disposed near the other end of the substrate, so that the traces of the first and second high speed signal lines run from one end of the substrate to the other end of the substrate.

In some embodiments of the present application, a first matching circuit is disposed on the first high-speed signal line, and a second matching circuit is disposed on the second high-speed signal line; the first matching circuit is arranged on the first high-speed signal line and close to the first anode 612, and the first matching circuit is used for performing impedance matching between the twin laser chip 610 and the first high-speed signal line; a second matching circuit for performing impedance matching between the twin laser chip 610 and the second high-speed signal line is provided on the second high-speed signal line near the second anode 613. The first and second matching circuits may comprise a resistor, or a combination of a resistor and a capacitor. Optionally, the first matching circuit and the second matching circuit each include a thin film resistor, the first thin film resistor is serially connected to the first high-speed signal line and is close to the first anode 612, and the second thin film resistor is serially connected to the second high-speed signal line and is close to the second anode 613.

In some embodiments of the present application, the first high-speed signal line is a straight high-speed signal line, the second high-speed signal line is a bent high-speed signal line, and a bending degree of the second high-speed signal line can be selected and converted according to a predetermined delay difference between the first high-speed signal line and between the first high-speed signal line and the second high-speed signal line.

Fig. 8 is a schematic top-surface structure diagram of a laser module according to an embodiment of the present disclosure. As shown in fig. 8, laser assembly 600 includes a twin laser chip 610 and a substrate 620, twin laser chip 610 is disposed on substrate 620, and the bottom surface of twin laser chip 610 is attached to the top surface of substrate 620. The first high speed signal line 621, the second high speed signal line 622, and the first reflow ground 623 are disposed on the top surface of the substrate 620. The first anode 612 is wire-bonded to the first high-speed signal line 621, the second anode 613 is wire-bonded to the second high-speed signal line 622, and the cathode (shielded) is soldered to the first reflow ground 623. In this embodiment, the length of the second high-speed signal line is greater than that of the first high-speed signal line to inject a high-speed signal having a predetermined delay difference into the ridge waveguide 611.

In this embodiment, the first and second high-speed signal lines 621 and 622 extend from one end of the substrate 620 to the other end of the substrate; alternatively, one end of the first high-speed signal line 621 is close to one end of the substrate 620, and the other end extends to the other end of the substrate 620, and one end of the second high-speed signal line 622 is located at one end of the substrate 620, and the other end extends to the other end of the substrate 620. In order to effectively control the bonding length of the first positive electrode 612 and the first high-speed signal line 621 and the bonding length of the second positive electrode 613 and the second high-speed signal line 622, the twin laser chip 610 is disposed at one end of the substrate 620.

In some embodiments of the present application, the first high speed signal line 621 is a straight high speed signal line, and the second high speed signal line 622 has a bent shape perpendicular to the first high speed signal line 621 at one end; the other end of the second high-speed signal line 622 is parallel to the first high-speed signal line 621, i.e., the second high-speed signal line 622 is parallel to the first high-speed signal line 621 from the bent portion of the second high-speed signal line 622 to the other end, so that the other ends of the first high-speed signal line 621 and the second high-speed signal line 622 are connected to the signal input circuit. In some embodiments of the present application, the second high speed signal line 622 has one bend, but is not limited to one bend.

As shown in fig. 8, the first high speed signal line 621 is connected to the first positive electrode 612 in series with the first thin film resistor 624, and the second high speed signal line 622 is connected to the second positive electrode 613 in series with the first thin film resistor 625.

As shown in fig. 8, the first reflow ground 623 of the top surface of the substrate 620 is disposed around the first and second high-speed signal lines 621 and 622, and further, the first and second high-speed signal lines 621 and 622 are spaced apart by the first reflow ground 623. Fig. 9 is a schematic bottom view of a laser module according to an embodiment of the present disclosure, which is a view from another direction of fig. 8, showing a bottom surface of the laser module shown in fig. 8. In some embodiments of the present application, as shown in fig. 9, a second reflow ground 626 is further disposed on the bottom surface of the substrate 620, a plurality of vias 627 are further disposed on the substrate 620, and the first reflow ground 623 on the top surface of the substrate 620 is electrically connected to the second reflow ground 626 on the bottom surface of the substrate 620 through the vias 627. This increases the area of the first reflow pad on the substrate 620 by the second reflow pad 626 on the bottom surface of the substrate 620, while also electrically connecting the first reflow pads 623 on the top surface of the substrate 620 together. Optionally, the vias 627 are uniformly distributed on the first reflow ground 623.

Fig. 10 is a schematic top view of another laser module according to an embodiment of the present disclosure. As shown in fig. 10, like the laser module 600 shown in fig. 8, the laser module 600 includes a twin laser chip 610 and a substrate 620, the twin laser chip 610 is disposed on the substrate 620, and the bottom surface of the twin laser chip 610 is connected to the top surface of the substrate 620. The difference from the laser module 600 shown in fig. 8 is that the second high speed signal line 622 has three bent high speed signal lines.

As shown in fig. 10, one end of the second high-speed signal line 622 is perpendicular to the first high-speed signal line 621, a portion near the other end is parallel to the first high-speed signal line 621, and the middle portion includes a plurality of bends, where there is a high-speed signal line parallel to the first high-speed signal line 621, but there may be no high-speed signal line parallel to the first high-speed signal line 621 in the embodiment of the present application.

As shown in fig. 10, the first reflow ground 623 of the top surface of the substrate 620 is disposed around the first and second high-speed signal lines 621 and 622. Fig. 11 is a schematic bottom view of another laser module according to an embodiment of the present disclosure, which is a view from another direction of fig. 10, showing a bottom surface of the laser module shown in fig. 10. In some embodiments of the present application, as shown in fig. 11, a second reflow ground 626 is further disposed on the bottom surface of the substrate 620, a plurality of vias 627 are further disposed on the substrate 620, and the first reflow ground 623 on the top surface of the substrate 620 is electrically connected to the second reflow ground 626 on the bottom surface of the substrate 620 through the vias 627. This increases the area of the first reflow pad on the substrate 620 by the second reflow pad 626 on the bottom surface of the substrate 620, while also electrically connecting the first reflow pads 623 on the top surface of the substrate 620 together. Optionally, the vias 627 are uniformly distributed on the first reflow ground 623.

In fig. 8 and 10, the first positive electrode 612 and the second positive electrode 613 are connected to the first high-speed signal line 621 and the second high-speed signal line 622 by wire bonding, but when the first positive electrode 612 and the second positive electrode 613 are connected to the first high-speed signal line 621 and the second high-speed signal line 622 by flip chip bonding, the structure of the substrate can be seen from the substrate 620 in the structure shown in fig. 8 and 10.

In the laser module 600 provided by the embodiment of the present application, the ridge waveguide 611 on the dual laser chip 610 is connected to the first anode 612 and the second anode 613 for injecting a high-speed signal, the first high-speed signal line 621 and the second high-speed signal line 622 are disposed on the substrate 620, the first anode 612 and the second anode 613 of the dual laser chip 610 are correspondingly connected to the first high-speed signal line 621 and the second high-speed signal line 622, and further the first high-speed signal line 621 and the second high-speed signal line 622 generate a predetermined delay difference for the high-speed signal injected into the ridge waveguide 611. Thus, the high-speed signal to be injected into the ridge waveguide 611 passes through the first high-speed signal line 621 and the second high-speed signal line 622, a preset time delay difference exists when the high-speed signal is injected into the ridge waveguide 611, the high-speed signal with the preset time delay difference is injected into the ridge waveguide, an electric and optical oscillation effect is formed in respective resonant cavities, then an optical and optical oscillation effect is performed, the high-speed modulated light generated by the double-laser structure has a specific phase difference for superposition by using the time delay difference of the high-speed signal injection, and further, a single laser 3dB bandwidth curve has a flattening effect at a higher frequency, so that compensation of an S21 bandwidth curve of a laser chip at a higher frequency position is realized, the 3dB bandwidth and the transmission rate are further improved, and modulation at a higher rate is achieved.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions in the embodiments of the present application.