Optical module

Abstract

The invention provides an optical module which comprises a circuit board, a substrate electrically connected with the circuit board, a laser chip installed on the substrate and an adapter plate installed on the laser chip, and the circuit board is provided with a driving signal line, a power supply bonding pad and a grounding bonding pad. The substrate is provided with a grounding conductive area in routing connection with the grounding bonding pad, a power supply line in routing connection with the power supply bonding pad, and a high-frequency signal line in routing connection with the driving signal line. The laser chip comprises a light-emitting area and a modulation area, and a light-emitting electrode connected with the light-emitting area and a modulation electrode connected with the modulation area are arranged on the top surface of the laser chip; a grounding conductive layer, a conductive wire and a signal wire are arranged on the side face, facing the substrate, of the adapter plate, the conductive wire is welded to the light-emitting electrode and the power supply wire, and the signal wire is welded to the modulation electrode and the high-frequency signal wire. According to the invention, the adapter plate is additionally arranged, the electric connection between the laser chip and the substrate is realized through the adapter plate, the wiring for connecting the laser chip and the substrate is replaced, and the signal bandwidth of the laser chip is effectively improved.

Description

Technical Field

[0001] The present disclosure relates to the field of optical communication technologies, and in particular, to an optical module. Background Art

[0002] With the development of new services and application models such as cloud computing, mobile Internet, and video, the development and progress of optical communication technologies have become increasingly important. In optical communication technologies, an optical module is a tool for realizing the mutual conversion of optical and electrical signals, and is one of the key components in optical communication devices. Moreover, with the development needs of optical communication technologies, the transmission rate of optical modules is continuously increasing.

[0003] The optical module includes an optical emission component, which is one of the important components determining the transmission rate of the optical module. The optical emission component includes a laser chip, and the bandwidth of the laser chip will limit the rate supported by the optical emission component; during the packaging process of the laser chip, transmission line matching, microwave reflection, high-frequency transmission loss, etc. will directly affect the bandwidth of the laser chip. Summary of the Invention

[0004] Embodiments of the present disclosure provide an optical module to improve the signal bandwidth of a laser chip.

[0005] In a first aspect, the present disclosure provides an optical module, including:

[0006] A circuit board, on which drive signal lines, power supply pads, and ground pads are provided;

[0007] An optical emission component, electrically connected to the circuit board, and the optical emission component is used to generate and output an optical signal; wherein, the optical emission component includes:

[0008] A substrate, on which a ground conductive region, a power supply line, and a high-frequency signal line are provided, the power supply line is not connected to the high-frequency signal line and the ground conductive region, the ground conductive region is wire-bonded to the ground pad, one end of the power supply line is wire-bonded to the power supply pad, and one end of the high-frequency signal line is wire-bonded to the drive signal line;

[0009] A laser chip, mounted on the substrate, the laser chip includes a light-emitting region and a modulation region, a light-emitting electrode and a modulation electrode are provided on the top surface of the laser chip, the light-emitting electrode is connected to the light-emitting region, and the modulation electrode is connected to the modulation region;

[0010] The adapter board is installed on the laser chip. A ground conductive layer, a conductive wire, and a signal wire are arranged on the side surface of the adapter board facing the substrate. The conductive wire is not connected to the signal wire and the ground conductive layer. One end of the conductive wire is welded to the light-emitting electrode, and the other end of the conductive wire is welded to the other end of the power supply wire to transmit a bias current to the light-emitting region. One end of the signal wire is welded to the modulation electrode, and the other end of the signal wire is welded to the other end of the high-frequency signal wire to transmit a current signal to the modulation region.

[0011] In a second aspect, the present disclosure provides an optical module, including:

[0012] A circuit board, on which a driving signal wire, a power supply pad, and a ground pad are arranged;

[0013] An optical emission component, electrically connected to the circuit board, and the optical emission component is used to generate and output an optical signal; wherein, the optical emission component includes:

[0014] A substrate, on which a ground conductive region, a power supply wire, and a high-frequency signal wire are arranged. The power supply wire is not connected to the high-frequency signal wire and the ground conductive region. The ground conductive region is wire-bonded to the ground pad, one end of the power supply wire is wire-bonded to the power supply pad, and one end of the high-frequency signal wire is wire-bonded to the driving signal wire;

[0015] A laser chip, installed on the substrate. The laser chip includes a light-emitting region and a modulation region. A light-emitting electrode, a modulation electrode, a first ground electrode, and a second ground electrode are arranged on the top surface of the laser chip. The light-emitting electrode is connected to the light-emitting region, the modulation electrode is connected to the modulation region, and the first ground electrode and the second ground electrode are located on both sides of the modulation electrode;

[0016] An adapter board, installed on the laser chip. A ground conductive layer, a conductive wire, and a signal wire are arranged on the side surface of the adapter board facing the substrate. The conductive wire is not connected to the signal wire and the ground conductive layer. One end of the conductive wire is welded to the light-emitting electrode, and the other end of the conductive wire is welded to the other end of the power supply wire to transmit a bias current to the light-emitting region. One end of the signal wire is welded to the modulation electrode, and the other end of the signal wire is welded to the other end of the high-frequency signal wire to transmit a current signal to the modulation region. One end of the ground conductive layer is welded to the first ground electrode and the second ground electrode, and the other end of the ground conductive layer is welded to the ground conductive region.

[0017] As can be seen from the above embodiments, the optical module provided by the present disclosure includes a circuit board and an optical emission component. The optical emission component is electrically connected to the circuit board. A drive signal line, a power supply pad, and a ground pad are provided on the circuit board. The optical emission component includes a substrate, a laser chip, and an adapter board. A ground conductive region, a power supply line, and a high-frequency signal line are provided on the substrate. The power supply line is not connected to the high-frequency signal line and the ground conductive region. The ground conductive region is wire-bonded to the ground pad, so that the power supply line and the high-frequency signal line are not grounded. One end of the power supply line is wire-bonded to the power supply pad to transmit the bias current transmitted by the circuit board to the power supply line. One end of the high-frequency signal line is wire-bonded to the drive signal line to transmit the current signal transmitted by the drive signal line to the high-frequency signal line. The laser chip is mounted on the substrate. The laser chip includes a light-emitting region and a modulation region. A light-emitting electrode and a modulation electrode are provided on the top surface of the laser chip. The light-emitting electrode is connected to the light-emitting region, and the modulation electrode is connected to the modulation region. The adapter board is mounted on the laser chip. A ground conductive layer, a conductive wire, and a signal line are provided on the side surface of the adapter board facing the substrate. The conductive wire is not connected to the signal line and the ground conductive layer. One end of the conductive wire is soldered to the light-emitting electrode, and the other end of the conductive wire is soldered to the other end of the power supply line to transmit the bias current transmitted by the power supply line to the light-emitting electrode through the conductive wire on the adapter board to transmit the bias current to the light-emitting region, so that the light-emitting region generates a laser beam. One end of the signal line is soldered to the modulation electrode, and the other end of the signal line is soldered to the other end of the high-frequency signal line to transmit the current signal transmitted by the high-frequency signal line to the modulation electrode through the signal line on the adapter board to transmit the current signal to the modulation region, so that the modulation region modulates the laser beam and the current signal to output a modulated optical signal.

[0018] In the optical module provided by the present disclosure, an adapter board is added in the optical emission component, and the electrical connection between the laser chip and the substrate is realized through the adapter board to replace the wire bonding that currently connects the laser chip and the substrate, which can avoid the impedance mismatch problem caused by wire bonding, thereby avoiding the influence of signal line matching on the bandwidth of the laser chip and effectively improving the signal bandwidth. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the present disclosure, the following will briefly introduce the drawings required for use in some embodiments of the present disclosure. Obviously, the drawings in the following description are only the drawings of some embodiments of the present disclosure. For those of ordinary skill in the art, other drawings can also be obtained according to these drawings. In addition, the drawings in the following description can be regarded as schematic diagrams, and do not limit the actual dimensions of the products, the actual processes of the methods, the actual timings of the signals, etc. involved in the embodiments of the present disclosure.

[0020] Figure 1 It is a partial structure diagram of an optical communication system provided according to some embodiments of the present disclosure;

[0021] Figure 2A partial structure diagram of a host computer provided according to some embodiments of the present disclosure;

[0022] Figure 3 A structure diagram of an optical module provided according to some embodiments of the present disclosure;

[0023] Figure 4 An exploded view of an optical module provided according to some embodiments of the present disclosure;

[0024] Figure 5 A structure diagram of an optical emission component in an optical module provided according to some embodiments of the present disclosure;

[0025] Figure 6 An exploded view of an optical emission component in an optical module provided according to some embodiments of the present disclosure;

[0026] Figure 7 A structure of a laser chip in an optical module provided according to some embodiments of the present disclosure Figure 1 ;

[0027] Figure 8 A connection diagram of a circuit board and a laser chip in an optical module provided according to some embodiments of the present disclosure;

[0028] Figure 9 A partial connection of a circuit board and a laser chip in an optical module provided according to some embodiments of the present disclosure Figure 1 ;

[0029] Figure 10 An assembly diagram of a laser chip and a substrate in an optical module provided according to some embodiments of the present disclosure;

[0030] Figure 11 A top view of a laser chip in an optical module provided according to some embodiments of the present disclosure;

[0031] Figure 12 A structure diagram of an adapter board in an optical module provided according to some embodiments of the present disclosure;

[0032] Figure 13 An assembly diagram of a substrate, a laser chip and an adapter board in an optical module provided according to some embodiments of the present disclosure;

[0033] Figure 14 An assembly perspective of a substrate, a laser chip and an adapter board in an optical module provided according to some embodiments of the present disclosure Figure 1 ;

[0034] Figure 15 An assembly perspective of a substrate, a laser chip and an adapter board in an optical module provided according to some embodiments of the present disclosure Figure 2 ;

[0035] Figure 16 A partial connection between a circuit board and a laser chip in an optical module provided according to some embodiments of the present disclosure Figure 2 ;

[0036] Figure 17 The structure of a laser chip in an optical module provided according to some embodiments of the present disclosure Figure 2 ;

[0037] Figure 18a The structural diagram of a deep-etched waveguide in an optical module provided according to some embodiments of the present disclosure;

[0038] Figure 18b The mode spot schematic diagram of an optical waveguide in an optical module provided according to some embodiments of the present disclosure;

[0039] Figure 18c The lateral divergence angle curve of a laser chip in an optical module provided according to some embodiments of the present disclosure Figure 1 ;

[0040] Figure 18d The longitudinal divergence angle curve of a laser chip in an optical module provided according to some embodiments of the present disclosure Figure 1 ;

[0041] Figure 19 The structure of a laser chip in an optical module provided according to some embodiments of the present disclosure Figure 3 ;

[0042] Figure 20 The partial top view of a laser chip in an optical module provided according to some embodiments of the present disclosure;

[0043] Figure 21 The partial structural top view of a laser chip in an optical module provided according to some embodiments of the present disclosure

[0044] Figure 22 The waveguide structure diagram of a laser chip in an optical module provided according to some embodiments of the present disclosure

[0045] Figure 23a For Figure 21 The cross-sectional view at A-A in

[0046] Figure 23b For Figure 21 The cross-sectional view at C-C in

[0047] Figure 23c For Figure 21 The cross-sectional view at B-B in

[0048] Figure 24aThe transmittance relationship of a transition optical waveguide in an optical module provided according to some embodiments of the present disclosure Figure 1 ;

[0049] Figure 24b The transmittance relationship of a transition optical waveguide in an optical module provided according to some embodiments of the present disclosure Figure 2 ;

[0050] Figure 24c The transmittance relationship of a transition optical waveguide in an optical module provided according to some embodiments of the present disclosure Figure 3 ;

[0051] Figure 25a The simulation result of the overall far - field morphology of a laser chip in an optical module provided according to some embodiments of the present disclosure Figure 1 ;

[0052] Figure 25b The simulation result of the overall far - field morphology of a laser chip in an optical module provided according to some embodiments of the present disclosure Figure 2 ;

[0053] Figure 25c The lateral divergence angle curve of a laser chip in an optical module provided according to some embodiments of the present disclosure Figure 2 ;

[0054] Figure 25d The longitudinal divergence angle curve of a laser chip in an optical module provided according to some embodiments of the present disclosure Figure 2 。 Detailed implementation manners

[0055] Next, some embodiments of the present disclosure will be clearly and detailedly described in conjunction with the accompanying drawings. However, the described embodiments are only a part of the embodiments of the present disclosure, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments provided by the present disclosure fall within the scope of protection of the present disclosure.

[0056] Unless otherwise required by the context, throughout the specification and claims, the term "comprising" is construed in an open, inclusive sense, i.e., "including, but not limited to"; the terms "first" and "second" should not be construed as indicating or implying relative importance or an upper limit on quantity; the term "plurality" means two or more; the term "connected" should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or integral, can be directly connected, or can be indirectly connected through an intermediate medium; the use of the term "adapted to" or "configured to" implies open and inclusive language and does not exclude a device adapted to or configured to perform additional tasks or steps; descriptions such as "parallel", "perpendicular", "identical", "consistent", "flush", etc. are not limited to absolute mathematical relationships but also include an acceptable error range in practice and also include differences due to manufacturing reasons based on the same design concept.

[0057] In optical communication technology, in order to establish information transfer between information processing devices, it is necessary to load information onto light and utilize the propagation of light to achieve information transfer. Here, the light loaded with information is the optical signal. When the optical signal is transmitted in the information transmission device, the loss of optical power can be reduced, so high-speed, long-distance, and low-cost information transfer can be achieved. The signals that information processing devices can recognize and process are electrical signals. Information processing devices generally include an Optical Network Unit (ONU), gateway, router, switch, mobile phone, computer, server, tablet computer, television, etc., and information transmission devices generally include optical fibers and optical waveguides, etc.

[0058] The optical module can realize the mutual conversion between optical signals and electrical signals between the information processing device and the information transmission device. For example, at least one of the optical signal input end or the optical signal output end of the optical module is connected to an optical fiber, and at least one of the electrical signal input end or the electrical signal output end of the optical module is connected to an optical network terminal; the first optical signal from the optical fiber is transmitted to the optical module, the optical module converts the first optical signal into a first electrical signal, and transmits the first electrical signal to the optical network terminal; the second electrical signal from the optical network terminal is transmitted to the optical module, the optical module converts the second electrical signal into a second optical signal, and transmits the second optical signal to the optical fiber. Since information can be transmitted between multiple information processing devices through electrical signals, therefore, at least one of the multiple information processing devices needs to be directly connected to the optical module, rather than all information processing devices being directly connected to the optical module. Here, the information processing device directly connected to the optical module is called the host computer of the optical module. In addition, the optical signal input end or the optical signal output end of the optical module can be called the optical port, and the electrical signal input end or the electrical signal output end of the optical module can be called the electrical port.

[0059] Figure 1 It is a partial structural diagram of an optical communication system provided according to some embodiments of the present disclosure. As Figure 1 shown, the optical communication system mainly includes a remote information processing device 1000, a local information processing device 2000, a host computer 100, an optical module 200, an optical fiber 101, and a network cable 103.

[0060] One end of the optical fiber 101 extends in the direction of the remote information processing device 1000, and the other end of the optical fiber 101 is connected to the optical module 200 through the optical port of the optical module 200. The optical signal can be totally reflected in the optical fiber 101, and the propagation of the optical signal in the total reflection direction can almost maintain the original optical power. The optical signal undergoes multiple total reflections in the optical fiber 101 to transmit the optical signal from the remote information processing device 1000 to the optical module 200, or to transmit the optical signal from the optical module 200 to the remote information processing device 1000, thereby realizing long-distance and low-power-loss information transmission.

[0061] The optical communication system may include one or more optical fibers 101, and the optical fiber 101 is detachably or fixedly connected to the optical module 200. The host computer 100 is configured to provide a data signal to the optical module 200, or receive a data signal from the optical module 200, or monitor or control the working state of the optical module 200.

[0062] The host computer 100 includes a housing substantially in the shape of a cuboid, and an optical module interface 102 provided on the housing. The optical module interface 102 is configured to access the optical module 200 to establish a unidirectional or bidirectional electrical signal connection between the host computer 100 and the optical module 200.

[0063] The host computer 100 further includes an external power interface, which can access an electrical signal network. For example, the external power interface includes a Universal Serial Bus (USB) interface or a network cable interface 104. The network cable interface 104 is configured to access a network cable 103, so that the host computer 100 establishes a unidirectional or bidirectional electrical signal connection with the network cable 103. One end of the network cable 103 is connected to the local information processing device 2000, and the other end of the network cable 103 is connected to the host computer 100, so as to establish an electrical signal connection between the local information processing device 2000 and the host computer 100 through the network cable 103. For example, a third electrical signal sent by the local information processing device 2000 is transmitted into the host computer 100 through the network cable 103. The host computer 100 generates a second electrical signal according to the third electrical signal. The second electrical signal from the host computer 100 is transmitted to the optical module 200. The optical module 200 converts the second electrical signal into a second optical signal and transmits the second optical signal to the optical fiber 101. The second optical signal is transmitted in the optical fiber 101 to the remote information processing device 1000. For example, a first optical signal from the remote information processing device 1000 propagates through the optical fiber 101. The first optical signal from the optical fiber 101 is transmitted to the optical module 200. The optical module 200 converts the first optical signal into a first electrical signal. The optical module 200 transmits the first electrical signal to the host computer 100. The host computer 100 generates a fourth electrical signal according to the first electrical signal and transmits the fourth electrical signal into the local information processing device 2000. It should be noted that an optical module is a tool for realizing the mutual conversion between optical signals and electrical signals. In the above conversion process of optical signals and electrical signals, the information does not change, but the encoding and decoding methods of the information can change.

[0064] In addition to including an optical network terminal, the host computer 100 further includes an Optical Line Terminal (OLT), an Optical Network Terminal (ONT), or a data center server, etc.

[0065] Figure 2 It is a partial structure diagram of a host computer provided according to some embodiments of the present disclosure. To clearly show the connection relationship between the optical module 200 and the host computer 100, Figure 2 only the structure of the host computer 100 related to the optical module 200 is shown. As Figure 2 shown, the host computer 100 further includes a Printed Circuit Board (PCB) 105 disposed in the housing, a cage 106 disposed on the surface of the PCB 105, a radiator 107 disposed on the cage 106, and an electrical connector disposed inside the cage 106. The electrical connector is configured to access the electrical port of the optical module 200; the radiator 107 has raised structures such as fins for increasing the heat dissipation area.

[0066] The optical module 200 is inserted into the cage 106 of the host computer 100, and the cage 106 fixes the optical module 200. The heat generated by the optical module 200 is conducted to the cage 106 and then diffused through the radiator 107. After the optical module 200 is inserted into the cage 106, the electrical port of the optical module 200 is connected to the electrical connector inside the cage 106, so as to establish a two-way electrical signal connection between the optical module 200 and the host computer 100. In addition, the optical port of the optical module 200 is connected to the optical fiber 101, so as to establish a two-way optical signal connection between the optical module 200 and the optical fiber 101.

[0067] Figure 3 It is a structural diagram of an optical module provided according to some embodiments of the present disclosure. Figure 4 It is an exploded view of an optical module provided according to some embodiments of the present disclosure. As Figure 3 and Figure 4 shown, the optical module 200 includes a shell, a circuit board 300 disposed in the shell, and an optical transmitting component 400 and an optical receiving component 500 disposed in the shell. However, the present disclosure is not limited thereto. In some embodiments, the optical module 200 includes one of the optical transmitting component 400 and the optical receiving component 500.

[0068] The shell includes an upper shell 201 and a lower shell 202. The upper shell 201 covers the lower shell 202 to form the above-mentioned shell having two openings 204 and 205; the outer contour of the shell generally presents a rectangular body.

[0069] In some embodiments, the lower shell 202 includes a bottom plate 2021 and two lower side plates 2022 located on both sides of the bottom plate 2021 and perpendicular to the bottom plate 2021; the upper shell 201 includes a cover plate 2011, and the cover plate 2011 covers the two lower side plates 2022 of the lower shell 202 to form the above-mentioned shell.

[0070] In some embodiments, the lower shell 202 includes a bottom plate 2021 and two lower side plates 2022 located on both sides of the bottom plate 2021 and perpendicular to the bottom plate 2021; the upper shell 201 includes a cover plate 2011 and two upper side plates located on both sides of the cover plate 2011 and perpendicular to the cover plate 2011. The two upper side plates are combined with the two lower side plates 2022 to realize the upper shell 201 covering the lower shell 202.

[0071] The direction where the line connecting the two openings 204 and 205 is located may be consistent with the length direction of the optical module 200 (for example Figure 3 the direction shown by the x-axis in Figure 3 ), or may be inconsistent with the length direction of the optical module 200. For example, the opening 204 is located at the right end of the optical module 200 (Figure 3 the negative end of the X-axis in the figure). Alternatively, the opening 204 is located at the end of the optical module 200, while the opening 205 is located at the side of the optical module 200. The opening 204 is an electrical port, and the gold finger 301 of the circuit board 300 extends from the electrical port and is inserted into the electrical connector of the host computer 100; the opening 205 is an optical port and is configured to access an external optical fiber 101 so that the optical fiber 101 connects the optical transmitting component 400 and the optical receiving component 500 in the optical module 200. In some embodiments, Figure 3 the X-axis direction in the figure is the left-right direction.

[0072] Adopting the assembly method of combining the upper housing 201 and the lower housing 202 facilitates the installation of the circuit board 300, the optical transmitting component 400, the optical receiving component 500, etc. into the above-mentioned housing, and the upper housing 201 and the lower housing 202 can encapsulate and protect the above-mentioned devices. In addition, when assembling the circuit board 300, the optical transmitting component 400, the optical receiving component 500, etc., it is convenient for the deployment of the positioning components, heat dissipation components, and electromagnetic shielding components of these devices, which is conducive to the automated implementation of production.

[0073] In some embodiments, the upper housing 201 and the lower housing 202 are made of metal materials, which is beneficial to achieve electromagnetic shielding and heat dissipation.

[0074] In some embodiments, the optical module 200 further includes an unlocking component 600 located outside its housing. The unlocking component 600 is configured to achieve a fixed connection between the optical module 200 and the host computer, or to release the fixed connection between the optical module 200 and the host computer.

[0075] For example, the unlocking component 600 is located outside the two lower side plates 2022 of the lower housing 202 and includes a latching component that matches the cage 106 of the host computer 100. When the optical module 200 is inserted into the cage 106, the latching component of the unlocking component 600 fixes the optical module 200 in the cage 106; when the unlocking component 600 is pulled, the latching component of the unlocking component 600 moves accordingly, thereby changing the connection relationship between the latching component and the host computer to release the fixation of the optical module 200 and the host computer, so that the optical module 200 can be withdrawn from the cage 106.

[0076] The circuit board 300 includes circuit traces, electronic components, chips, etc. The electronic components and chips are connected according to the circuit design through the circuit traces to achieve functions such as power supply, electrical signal transmission, and grounding. The electronic components may include, for example, capacitors, resistors, triodes, Metal-Oxide-Semiconductor Field-Effect Transistors (MOSFETs). The chips may include, for example, Microcontroller Units (MCUs), laser driver chips, Transimpedance Amplifiers (TIAs), Limiting Amplifiers (LAs), Clock and Data Recovery (CDR) chips, power management chips, and Digital Signal Processing (DSP) chips.

[0077] The circuit board 300 is generally a rigid circuit board. Due to its relatively hard material, the rigid circuit board can also achieve a bearing function. For example, the rigid circuit board can stably bear the above-mentioned electronic components and chips; the rigid circuit board can also be inserted into the electrical connectors in the cage 106 of the host computer 100.

[0078] The circuit board 300 also includes a gold finger 301 formed on its end surface. The gold finger 301 is composed of a plurality of independent pins. The circuit board 300 is inserted into the cage 106, and the gold finger 301 is electrically connected to the electrical connector in the cage 106. The gold finger 301 can be provided only on the surface of one side of the circuit board 300 (for example, Figure 4 the upper surface shown), or can be provided on the upper and lower surfaces of the circuit board 300 to provide a larger number of pins, so as to adapt to occasions with a large demand for the number of pins. The gold finger 301 is configured to establish an electrical connection with the host computer to achieve functions such as power supply, grounding, Inter-Integrated Circuit (I2C) signal transmission, and data signal transmission. Of course, flexible circuit boards are also used in some optical modules. The flexible circuit board is generally used in cooperation with the rigid circuit board as a supplement to the rigid circuit board.

[0079] At least one of the optical transmitting component 400 or the optical receiving component 500 is located on the side of the circuit board 300 away from the gold finger 301.

[0080] In some embodiments, the optical transmitting component 400 and the optical receiving component 500 are physically separated from the circuit board 300 respectively, and then electrically connected to the circuit board 300 through corresponding flexible circuit boards or electrical connectors respectively.

[0081] In some embodiments, at least one of the optical transmitting component 400 or the optical receiving component 500 can be directly disposed on the circuit board 300. For example, at least one of the optical transmitting component 400 or the optical receiving component 500 can be disposed on the surface of the circuit board 300 or on the side of the circuit board 300.

[0082] Referring to Figure 4 , the optical module provided by the embodiments of the present disclosure further includes a round-square tube body 1100. The optical transmitting component 400 and the optical receiving component 500 are disposed on the round-square tube body 1100. The optical transmitting component 400 is used to generate and output signal light, and the optical receiving component 500 is used to receive signal light from outside the optical module.

[0083] An optical fiber adapter is disposed on the round-square tube body 1100. The optical fiber adapter is used to realize the connection between the optical module and an external optical fiber. And a lens assembly is usually disposed in the round-square tube body 1100. The lens assembly is used to change the propagation direction of the output signal light of the optical transmitting component 400 or the signal light input from the external optical fiber. The optical transmitting component 400 and the optical receiving component 500 are physically separated from the circuit board 300. Therefore, it is difficult for the optical transmitting component 400 and the optical receiving component 500 to be directly connected to the circuit board 300. In this application, the optical transmitting component 400 and the optical receiving component 500 are electrically connected to the circuit board 300 through flexible circuit boards respectively.

[0084] Referring to Figure 4 , the optical transmitting component 400 is disposed on the round-square tube body 1100 and is coaxial with the optical fiber adapter of the round-square tube body 1100. The optical receiving component 500 is disposed on the side of the round-square tube body 1100 and is not coaxial with the optical fiber adapter of the round-square tube body 1100. In some embodiments, the optical transmitting component 400 can also be non-coaxial with the optical fiber adapter, and the optical receiving component 500 is coaxial with the optical fiber adapter.

[0085] Disposing the optical transmitting component 400 and the optical receiving component 500 through the round-square tube body 1100 is convenient for realizing the control of the signal light transmission optical path on the one hand, and is convenient for realizing the compact design inside the optical module and reducing the space occupied by the signal light transmission optical path on the other hand. In addition, with the development of the wavelength division multiplexing technology, in some optical modules, there are more than one optical transmitting component 400 and optical receiving component 500 disposed on the round-square tube body 1100.

[0086] In some embodiments, a dichroic mirror is further disposed in the round-square tube body 1100. The propagation direction of the signal light to be received by the optical receiving component 500 is changed through the dichroic mirror, or the propagation direction of the signal light generated by the optical transmitting component 400 is changed, which is convenient for the optical receiving component 500 to receive the signal light or the output of the signal light generated by the optical transmitting component 400.

[0087] In some embodiments, the assembly structure of the optical transmitting component 400 and the optical receiving component 500 is not limited to Figure 3With Figure 4 the structure shown, it can also be other assembly combination structures. For example, the optical emission component 400 and the optical reception component 500 are arranged on different tube bodies. This embodiment only takes Figure 3 and Figure 4 the structure shown as an example.

[0088] Figure 5 FIG. 0 is a structural diagram of an optical emission component in an optical module according to some embodiments of the present disclosure, Figure 6 FIG. 1 is an exploded view of an optical emission component in an optical module according to some embodiments of the present disclosure, Figure 7 FIG. 2 is a structure of a laser chip in an optical module according to some embodiments of the present disclosure Figure 1 . As Figure 5 , Figure 6 and Figure 7 shown, the optical emission component 400 provided in the embodiments of the present disclosure includes a base 410, a cap 420, and other optoelectronic devices disposed in the base 410 and the cap 420. The cap 420 covers one end of the base 410. A plurality of pins are provided on the base 410. The pins are used to realize the electrical connection between the flexible circuit board and the optoelectronic devices in the optical emission component 400, and further realize the electrical connection between the optical emission component 400 and the circuit board 300. This embodiment only takes Figure 5 the structure shown as an example.

[0089] The optoelectronic devices on the base 410 include a laser assembly 900. The laser assembly 900 is used to generate signal light. The signal light passes through the cap 420 and enters the round-square tube body 1100. The signal light is then transmitted to the fiber optic adapter through the round-square tube body 1100 to transmit the signal light to the external optical fiber.

[0090] Referring to Figure 7 , the laser assembly 900 includes a substrate 910 and a laser chip 920. A circuit is laid on the upper surface of the substrate 910. The laser chip 920 is wire-bonded to the circuit on the substrate 910 so that the laser chip 920 generates signal light.

[0091] In some embodiments, the laser chip 920 can be an electro-absorption modulated laser (EML). The EML laser chip, the substrate 910, and the bonding wires between the EML laser chip and the substrate 910 are encapsulated to form an EML laser assembly. The EML laser chip includes a light-emitting region and a modulation region. A light-emitting electrode and a modulation electrode are provided on the surface of the EML laser chip. The light-emitting electrode is electrically connected to the light-emitting region to transmit a bias current to the light-emitting region through the light-emitting electrode so that the light-emitting region generates a laser beam. The modulation electrode is electrically connected to the modulation region to transmit a current signal to the modulation region through the modulation electrode so that the modulation region modulates the laser beam and the current signal to obtain a modulated optical signal.

[0092] In the embodiments of the present disclosure, the structure of the laser component 900 is not limited to Figure 7 the structure shown, and it can also be a laser component formed by other structures. The substrate 910 can be a ceramic substrate, but is not limited to a ceramic substrate.

[0093] Figure 8 FIG. is a connection diagram of a circuit board and a laser chip in an optical module according to some embodiments of the present disclosure, Figure 9 is a partial connection of a circuit board and a laser chip in an optical module according to some embodiments of the present disclosure Figure 1 . As Figure 8 and Figure 9 shown, for the emission of optical signals, a DSP chip is mounted on the surface of the circuit board 300. The DSP chip is connected to the gold finger 301 through a signal line. The electrical signal provided by the host computer 100 is transmitted to the DSP chip via the gold finger 301; drive signal lines are arranged on the surface of the circuit board 300, and the drive signal lines extend from the DSP chip to the edge of the substrate 910. The drive signal lines transmit the high-frequency electrical signal output by the DSP chip to the optical transmitting component 400 to drive the laser chip 920 of the optical transmitting component 400 to generate an optical signal.

[0094] In some embodiments, to provide a flat optical bearing surface for the laser chip 920, the laser chip 920 is usually mounted on the substrate 910. A power supply line 9104 is arranged on the surface of the substrate 910. A welding pad 305 is provided on the circuit board 300. One end of the power supply line 9104 is electrically connected to the welding pad 305 through wire bonding, and the other end of the power supply line 9104 is electrically connected to the light-emitting area of the laser chip 920 through wire bonding. The bias current transmitted by the circuit board 300 is transmitted to the light-emitting area of the laser chip 920 through the power supply line 9104 to drive the laser chip 920 to generate a laser beam.

[0095] A high-frequency signal line 9103 is also arranged on the surface of the substrate 910. One end of the high-frequency signal line 9103 is connected to the drive signal line on the circuit board 300 to transmit the electrical signal transmitted by the drive signal line to the high-frequency signal line 9103; the other end of the high-frequency signal line 9103 is wire-bonded to the modulation area of the laser chip 920. The high-frequency electrical signal output by the DSP chip is transmitted to the laser chip 920 through the high-frequency signal line 9103, so that the laser chip 920 generates a modulated optical signal.

[0096] To achieve signal return of high-speed electrical signals, a ground pad is also provided on the circuit board 300, a grounding area is also arranged on the surface of the substrate 910, the bottom surface of the laser chip 920 is mounted on the grounding area, the power supply line 9104 is not connected to the high-frequency signal line 9103 and the grounding area, and the ground pad on the circuit board 300 is connected to the grounding area by wire bonding, so that the grounding area on the substrate 910 is grounded.

[0097] However, the RC parasitic parameters of the laser chip 920 itself have a great influence on the frequency response of the optical emission component, and the wire bonding between the laser chip 920 and the substrate 910 will also affect the frequency response of the laser chip 920. Especially when the parasitic capacitance of the laser chip 920 causes the chip bandwidth to be low, it seriously affects the performance of the laser chip 920, such as causing the rising edge of the eye diagram to become slower, the eye diagram not to open, and inter-symbol interference. Usually, the RF design means cannot meet the performance requirements, and a certain bandwidth compensation technology needs to be adopted to increase the high-frequency response bandwidth of the laser chip 920 and compensate for the performance deficiency of the optical chip itself.

[0098] Figure 10 An assembly diagram of a laser chip and a substrate in an optical module according to some embodiments of the present disclosure. Figure 11 A top view of a laser chip in an optical module according to some embodiments of the present disclosure. As Figure 10 And Figure 11 As shown, to improve the high-frequency response bandwidth of the laser chip 920, the laser component 900 provided by the embodiments of the present disclosure includes a substrate 910 and a laser chip 920. A grounding conductive area 9100 is provided on the upper surface of the substrate 910, and the laser chip 920 is mounted on the grounding conductive area 9100. A first avoidance portion 9112 is provided on the grounding conductive area 9100. One end of the first avoidance portion 9112 facing the circuit board 300 is provided with an opening. A power supply line 9104 is provided in the first avoidance portion 9112. One end of the power supply line 9104 is electrically connected to the power supply pad on the circuit board 300 by wire bonding, and the other end of the power supply line 9104 is connected to the light-emitting area of the laser chip 920 to provide the bias current transmitted by the power supply line 9104 to the light-emitting area of the laser chip 920, so that the light-emitting area generates a laser beam.

[0099] In some embodiments, the laser chip 920 is mounted in the upper right corner of the grounding conductive area 9100, and the power supply line 9104 extends from the left side of the substrate 910 ( Figure 10 the negative end of the X-axis shown) along the positive X-axis direction to the laser chip 920. In some embodiments, Figure 10 As shown, the X-axis direction is the left-right direction, the Y-axis direction is the up-down direction, and the Z-axis direction is the thickness direction.

[0100] Referring to Figure 11, a light-emitting electrode 9201 is provided on the top surface of the laser chip 920. The light-emitting electrode 9201 is connected to the light-emitting area of the laser chip 920. The light-emitting electrode 9201 is connected to one end of a power supply line 9104, and the other end of the power supply line 9104 is wire-bonded and electrically connected to a power supply pad on the circuit board 300. The bias current transmitted by the circuit board 300 is transmitted to the light-emitting electrode 9201 through the power supply line 9104 to provide a bias current to the light-emitting area of the laser chip 920, so that the light-emitting area generates a laser beam without a signal.

[0101] A second avoidance portion 9113 is further provided on the ground conductive area 9100. One end of the second avoidance portion 9113 facing the circuit board 300 is provided with an opening. A high-frequency signal line 9103 is provided in the second avoidance portion 9113. One end of the high-frequency signal line 9103 is wire-bonded and connected to a driving signal line on the circuit board 300, and the other end of the high-frequency signal line 9103 is connected to the modulation area of the laser chip 920 to transmit the current signal transmitted by the driving signal line to the modulation area through the high-frequency signal line 9103, so that the laser chip 920 generates a modulated optical signal.

[0102] Refer to Figure 11 , a modulation electrode 9202 is further provided on the top surface of the laser chip 920. The modulation electrode 9202 is connected to the modulation area of the laser chip 920, and the modulation electrode 9202 is connected to the high-frequency signal line 9103. The high-frequency electrical signal output by the DSP chip is transmitted to the modulation electrode 9202 through the driving signal line and the high-frequency signal line 9103 to provide a current signal to the modulation area of the laser chip 920, so that the modulation area modulates the laser beam generated by the light-emitting area and the current signal to output a modulated optical signal.

[0103] In some embodiments, the ground conductive area 9100 forms an enclosing trend around the high-frequency signal line 9103 to provide a return ground for the current information carried in the high-frequency signal line 9103, which is beneficial to reducing signal noise.

[0104] In some embodiments, the light-emitting electrode 9201 of the laser chip 920 is located on the left side of the modulation electrode 9202. The light-emitting end face of the laser chip 920 is located on the right side of the laser chip 920. The light-emitting direction of the laser chip 920 is emitted along the positive direction of the X axis.

[0105] Since the light-emitting electrode 9201 of the laser chip 920 is located on the left side of the modulation electrode 9202, the length dimension of the power supply line 9104 on the substrate 910 in the X-axis direction is smaller than the length dimension of the high-frequency signal line 9103. The right end of the power supply line 9104 can be flush with the light-emitting electrode 9201 in the X-axis direction, and the right end of the power supply line 9104 can also be flush with the light-emitting electrode 9201 in the Y-axis direction. The right end of the high-frequency signal line 9103 can be flush with the modulation electrode 9202 in the Y-axis direction.

[0106] Reference Figure 9 , in some embodiments, the electrical signal output by the DSP chip may be a differential signal, the driving signal lines on the circuit board 300 are differential signal lines, the differential signal lines include a first differential signal line 302 and a second differential signal line 303, the first differential signal line 302 is wire-bonded to the high-frequency signal line 9103, and the second differential signal line 303 is wire-bonded to the grounding conductive region 9100 on the substrate 910, so as to transmit the high-speed electrical signal output by the DSP chip to the high-frequency signal line 9103 through the differential signal lines.

[0107] Reference Figure 10 , a third avoidance portion 9114 is further provided on the grounding conductive region 9100, an opening is provided at one end of the third avoidance portion 9114 facing the circuit board 300, the third avoidance portion 9114 is located between the first avoidance portion 9112 and the second avoidance portion 9113, the third avoidance portion 9114 is communicated with the second avoidance portion 9113, a resistance pad 9106 is arranged in the third avoidance portion 9114, and the resistance pad 9106 is wire-bonded to the second differential signal line 303 on the circuit board 300.

[0108] There is a certain gap between the resistance pad 9106 and the grounding conductive region 9100, a first resistor 9107 is arranged between the resistance pad 9106 and the grounding conductive region 9100, one end of the first resistor 9107 is connected to the resistance pad 9106, and the other end of the first resistor 9107 is connected to the grounding conductive region.

[0109] For convenience of preparation, the first resistor 9107 has an impedance matching function, and finally makes the impedance output by the EML laser chip consistent with the characteristic impedance. Therefore, the first resistor 9107 can be called a matching resistor. Since the space of the substrate 910 is small, generally, the first resistor 9107 is a thin-film resistor, which is sintered through a region of the substrate 910.

[0110] Reference Figure 9 And Figure 10 , the first differential signal line 302 is wire-bonded to the high-frequency signal line 9103 to transmit the high-frequency electrical signal transmitted by the first differential signal line 302 to the high-frequency signal line 9103. The second differential signal line 303 is wire-bonded to the resistance pad 9106, the resistance pad 9106 is connected to the first resistor 9107, and the first resistor 9107 is connected to the grounding conductive region 9100, so that the second differential signal line 303 is grounded.

[0111] In some embodiments, the first avoidance portion 9112 extends from the left end of the substrate 910 ( Figure 10 the negative end of the X-axis shown) to the right end of the substrate 910 ( Figure 10(the positive end of the X-axis shown), the second avoidance portion 9113 extends from the left end to the right end of the substrate 910, the length dimension of the third avoidance portion 9114 in the X-axis direction is smaller than the length dimension of the second avoidance portion 9113, the second avoidance portion 9113 is communicated with the third avoidance portion 9114, and the second avoidance portion 9113 may or may not be communicated with the first avoidance portion 9112.

[0112] The first avoidance portion 9112 and the second avoidance portion 9113 divide the ground conductive region 9100 into a first ground conductive region 9101, a second ground conductive region 9111 and a third ground conductive region 9102, and the first ground conductive region 9101, the second ground conductive region 9111 and the third ground conductive region 9102 are arranged in sequence along the negative direction of the Y-axis (up and down direction).

[0113] Refer to Figure 9 , a ground pad is further arranged on the circuit board 300. The ground pad includes a first ground pad 304 and a second ground pad 306. The first ground pad 304 and the second ground pad 306 are located on both sides of the first differential signal line 302 and the second differential signal line 303. The first ground pad 304 is connected to the first ground conductive region 9101 or the second ground conductive region 9111 by wire bonding, and the second ground pad 306 is connected to the third ground conductive region 9102 by wire bonding, so as to realize the signal return of high-frequency electrical signals.

[0114] Refer to Figure 9 And Figure 10 , after arranging the power supply line 9104 and the high-frequency signal line 9103 on the substrate 910, the laser chip 920 is installed on the substrate 910. For example, the laser chip 920 is installed on the first ground conductive region 9101, and then one end of the power supply line 9104 is connected to the welding pad 305 by wire bonding. The other end of the power supply line 9104 can be connected to the light-emitting electrode 9201 on the top surface of the laser chip 920 by wire bonding to supply power to the light-emitting region of the laser chip 920, so that the light-emitting region generates a laser beam; then one end of the high-frequency signal line 9103 is connected to the first differential signal line 302 by wire bonding, and the other end of the high-frequency signal line 9103 can be connected to the modulation electrode 9202 on the top surface of the laser chip 920 by wire bonding to provide an electrical signal to the modulation region of the laser chip 920, so that the modulation region modulates the laser beam and the electrical signal to obtain a modulated optical signal.

[0115] In some embodiments, when wire bonding is used to connect the laser chip 920 to the substrate 910, the wire bonding will introduce inductive reactance into the circuit, resulting in impedance mismatch between the high-frequency signal line 9103 and the laser chip 920, thereby affecting the signal bandwidth. To avoid the impedance mismatch problem caused by wire bonding, the optical emission component 400 provided in the embodiments of the present disclosure further includes an adapter board. One end of the adapter board is welded to the laser chip 920 in a flip-chip manner, and the other end of the adapter board is welded to the substrate 910 in a flip-chip manner, so as to realize the connection between the laser chip 920 and the substrate 910 through the adapter board, such that there is no impedance mismatch problem in the connection between the laser chip 920, the adapter board and the substrate 910.

[0116] Figure 12 FIG. is a structural diagram of an adapter board in an optical module according to some embodiments of the present disclosure. Figure 13 FIG. is an assembly diagram of a substrate, a laser chip and an adapter board in an optical module according to some embodiments of the present disclosure. Figure 14 FIG. is an assembly perspective view of a substrate, a laser chip and an adapter board in an optical module according to some embodiments of the present disclosure. Figure 1 As Figure 12 、 Figure 13 and Figure 14 shown, the adapter board 980 is located above the substrate 910. A ground conductive layer 9800 is provided on the side surface (bottom surface) of the adapter board 980 facing the substrate 910. A fourth avoidance portion 9812 and a fifth avoidance portion 9813 are provided on the ground conductive layer 9800, and the fourth avoidance portion 9812 and the fifth avoidance portion 9813 are not connected. A conductive wire 9801 is provided in the fourth avoidance portion 9812. There is a gap between the conductive wire 9801 and the ground conductive layer 9800, so that the conductive wire 9801 is not connected to the ground conductive layer 9800. In some embodiments, the adapter board 980 is a ceramic board.

[0117] When the right end of the power supply line 9104 is flush with the light-emitting electrode 9201 in the X-axis direction, the conductive wire 9801 is arranged along the X-axis direction. The adapter board 980 is placed upside down on the top surface of the laser chip 920. The adapter board 980 covers a part of the power supply line 9104. The right end of the power supply line 9104 is correspondingly arranged with the left end of the conductive wire 9801. The light-emitting electrode 9201 of the laser chip 920 is correspondingly arranged with the right end of the conductive wire 9801. In this way, the right end of the power supply line 9104 is welded to the left end of the conductive wire 9801, and the right end of the conductive wire 9801 is welded to the light-emitting electrode 9201, so as to realize the electrical connection between the light-emitting electrode 9201 and the power supply line 9104 through the conductive wire 9801 on the adapter board 980, thereby providing a bias current to the light-emitting electrode 9201 through the adapter board 980, such that a laser beam is generated in the light-emitting area of the laser chip 920. In some embodiments, Figure 12 and Figure 14The X-axis direction shown is the left-right direction, and the Y-axis direction is the up-down direction.

[0118] Referring to Figure 12 , when the right end of the power supply line 9104 is flush with the light-emitting electrode 9201 in the Y-axis direction, the conductive line 9801 is arranged along the Y-axis direction, the adapter plate 980 is inverted and placed on the top surface of the laser chip 920, the adapter plate 980 covers part of the power supply line 9104, the right end of the power supply line 9104 is correspondingly arranged with the lower end of the conductive line 9801, and the light-emitting electrode 9201 of the laser chip 920 is correspondingly arranged with the upper end of the conductive line 9801. In this way, the right end of the power supply line 9104 is welded to the lower end of the conductive line 9801, and the upper end of the conductive line 9801 is welded to the light-emitting electrode 9201, so as to realize the electrical connection between the light-emitting electrode 9201 and the power supply line 9104 through the conductive line 9801 on the adapter plate 980, thereby providing a bias current to the light-emitting electrode 9201 through the adapter plate 980, so that a laser beam is generated in the light-emitting area of the laser chip 920.

[0119] In some embodiments, in order to reduce the length of the wire bonding between the power supply line 9104 and the power supply pad 305, the power supply line 9104 and the power supply pad are flush in the Y-axis direction. At this time, the power supply line 9104 and the light-emitting electrode 9201 may not be flush in the X-axis or Y-axis direction. In order to reduce the area size of the adapter plate 980, the power supply line 9104 can be set as a special-shaped line.

[0120] Referring to Figure 10 , the power supply line 9104 includes a first power supply line 9108, a second power supply line 9109 and a third power supply line 9110. The first power supply line 9108 is arranged along the X-axis direction, the second power supply line 9109 is arranged along the Y-axis direction, the third power supply line 9110 is arranged along the X-axis direction. The first power supply line 9108 and the second power supply line 9109 are located on the left side of the laser chip 920, the third power supply line 9110 is located on the lower side of the laser chip 920. One end of the first power supply line 9108 is connected to one end of the second power supply line 9109, the other end of the second power supply line 9109 is connected to one end of the third power supply line 9110, and the other end of the third power supply line 9110 is close to the light-emitting area of the laser chip 920. In this way, the first power supply line 9108, the second power supply line 9109 and the third power supply line 9110 form a Z-shaped power supply line.

[0121] The adapter board 980 is placed upside down on the top surface of the laser chip 920. The adapter board 980 covers a part of the third power supply line 9110. The right end of the third power supply line 9110 is correspondingly arranged with the lower end of the conductive wire 9801. The light-emitting electrode 9201 of the laser chip 920 is correspondingly arranged with the upper end of the conductive wire 9801. In this way, the right end of the third power supply line 9110 is welded to the lower end of the conductive wire 9801, and the upper end of the conductive wire 9801 is welded to the light-emitting electrode 9201, so as to realize the electrical connection between the light-emitting electrode 9201 and the power supply line 9104 through the conductive wire 9801 on the adapter board 980, thereby providing a bias current to the light-emitting electrode 9201 through the adapter board 980, so that a laser beam is generated in the light-emitting area of the laser chip 920.

[0122] Since the laser chip 920 is installed on the top surface of the substrate 910, there is a thickness difference between the top surface of the laser chip 920 and the top surface of the substrate 910. When the adapter board 980 is placed upside down on the top surface of the laser chip 920, there is a gap between the bottom surface of the adapter board 980 and the top surface of the substrate 910. If the welding between the conductive wire 9801 on the adapter board 980 and the power supply line 9104 is to be realized, the gap between the conductive wire 9801 and the power supply line 9104 can be filled with solder.

[0123] In some embodiments, referring to Figure 10 , a first metal protrusion 970, such as a metal column, can also be provided at the right end of the third power supply line 9110. The first metal protrusion 970 extends along the Z-axis direction from the third power supply line 9110. The thickness dimension of the first metal protrusion 970 in the Z-axis direction can be equal to or less than the thickness difference between the top surface of the laser chip 920 and the top surface of the substrate 910.

[0124] Referring to Figure 14 , when the adapter board 980 is placed upside down on the top surface of the laser chip 920, one end of the conductive wire 9801 on the adapter board 980 is directly welded to the light-emitting electrode 9201, and the other end of the conductive wire 9801 is welded to the first metal protrusion 970 to realize the electrical connection among the substrate 910, the laser chip 920 and the adapter board 980.

[0125] In some embodiments, referring to Figure 11 , the thickness dimension of the first metal protrusion 970 in the Z-axis direction can also be greater than the thickness difference between the top surface of the laser chip 920 and the top surface of the substrate 910. At this time, a second metal protrusion 9206 is provided on the light-emitting electrode 9201. The second metal protrusion 9206 extends along the Z-axis direction from the light-emitting electrode 9201. The thickness dimension of the second metal protrusion 9206 in the Z-axis direction is less than the thickness dimension of the first metal protrusion 970.

[0126] When the adapter board 980 is placed upside down above the laser chip 920, one end of the conductive wire 9801 on the adapter board 980 is welded to the second metal protrusion 9206, and the other end of the conductive wire 9801 is welded to the first metal protrusion 970, so as to realize the electrical connection among the substrate 910, the laser chip 920 and the adapter board 980.

[0127] In some embodiments, referring to Figure 10 and Figure 12 , a first metal protrusion 970 may also be provided on the third power supply line 9110, a second metal protrusion 9206 may be provided on the light-emitting electrode 9201, a third metal protrusion 9803 may be provided at one end of the conductive wire 9801, and a fourth metal protrusion 9804 may be provided at the other end of the conductive wire 9801. The first metal protrusion 970 and the third metal protrusion 9803 are arranged oppositely, the second metal protrusion 9206 and the fourth metal protrusion 9804 are arranged oppositely, and the sum of the thickness dimensions of the first metal protrusion 970 and the third metal protrusion 9803 in the Z-axis direction is equal to the sum of the thickness dimensions of the laser chip 920, the second metal protrusion 9206 and the fourth metal protrusion 9804 in the Z-axis direction.

[0128] When the adapter board 980 is placed upside down above the laser chip 920, the first metal protrusion 970 is welded to the third metal protrusion 9803, and the second metal protrusion 9206 is welded to the fourth metal protrusion 9804, so as to realize the electrical connection among the substrate 910, the laser chip 920 and the adapter board 980. Thus, the bias current transmitted by the power supply line 9104 is transmitted to the light-emitting electrode 9201 through the conductive wire 9801 on the adapter board 980, so that a laser beam is generated in the light-emitting area of the laser chip 920.

[0129] Referring to Figure 12 , a signal line 9802 is arranged in the fifth avoidance part 9813. The signal line 9802 is arranged along the Y-axis direction. The signal line 9802 is located in the left part of the ground conductive layer 9800 ( Figure 12 the negative end of the X-axis shown), the signal line 9802 is located on the left side of the conductive wire 9801, and there is a gap between the signal line 9802 and the ground conductive layer 9800. In this way, the signal line 9802 is not connected to the ground conductive layer 9800.

[0130] The adapter board 980 is placed upside down on the top surface of the laser chip 920. The adapter board 980 covers a part of the high-frequency signal line 9103. The right end of the high-frequency signal line 9103 is correspondingly arranged with the lower end of the signal line 9802. The modulation electrode 9202 of the laser chip 920 is correspondingly arranged with the upper end of the signal line 9802. In this way, the right end of the high-frequency signal line 9103 is welded to the lower end of the signal line 9802, and the upper end of the signal line 9802 is welded to the modulation electrode 9202, so as to realize the electrical connection between the modulation electrode 9202 and the high-frequency signal line 9103 through the signal line 9802 on the adapter board 980, thereby providing an electrical signal to the modulation area through the adapter board 980, so that the modulation area of the laser chip 920 modulates the electrical signal and the laser beam, so that the laser chip 920 generates a modulated optical signal.

[0131] Since the laser chip 920 is installed on the top surface of the substrate 910, there is a thickness difference between the top surface of the laser chip 920 and the top surface of the substrate 910. When the adapter board 980 is placed upside down on the top surface of the laser chip 920, there is a gap between the bottom surface of the adapter board 980 and the top surface of the substrate 910. To realize the welding between the signal line 9802 on the adapter board 980 and the high-frequency signal line 9103, the gap between the high-frequency signal line 9103 and the signal line 9802 can be filled with solder.

[0132] In some embodiments, referring to Figure 10 , a fifth metal protrusion 940, such as a metal column, can also be provided at the right end of the high-frequency signal line 9103. The fifth metal protrusion 940 extends along the Z-axis direction from the high-frequency signal line 9103. The thickness dimension of the fifth metal protrusion 940 in the Z-axis direction can be equal to or less than the thickness difference between the top surface of the laser chip 920 and the top surface of the substrate 910.

[0133] Referring to Figure 14 , when the adapter board 980 is placed upside down on the top surface of the laser chip 920, one end of the signal line 9802 on the adapter board 980 is directly welded to the modulation electrode 9202, and the other end of the signal line 9802 is welded to the fifth metal protrusion 940, so as to realize the signal connection between the substrate 910, the laser chip 920 and the adapter board 980, thereby transmitting an electrical signal to the modulation area of the laser chip 920 through the adapter board 980.

[0134] Referring to Figure 11 , the thickness dimension of the fifth metal protrusion 940 in the Z-axis direction can also be greater than the thickness difference between the top surface of the laser chip 920 and the top surface of the substrate 910. At this time, a sixth metal protrusion 9208 is provided on the modulation electrode 9202. The sixth metal protrusion 9208 extends along the Z-axis direction from the modulation electrode 9202. The thickness dimension of the sixth metal protrusion 9208 in the Z-axis direction is smaller than the thickness dimension of the fifth metal protrusion 940.

[0135] Referring toFigure 14 When the adapter board 980 is placed upside down above the laser chip 920, one end of the signal line 9802 on the adapter board 980 is welded to the fifth metal protrusion 940, and the other end of the signal line 9802 is welded to the sixth metal protrusion 9208, so as to realize the signal connection among the substrate 910, the laser chip 920 and the adapter board 980, and thus transmit an electrical signal to the modulation region of the laser chip 920 through the adapter board 980.

[0136] In some embodiments, referring to Figure 10 and Figure 12 , a fifth metal protrusion 940 may also be provided at the right end of the high-frequency signal line 9103, a sixth metal protrusion 9208 may be provided on the modulation electrode 9202, a seventh metal protrusion 9805 may be provided at one end of the signal line 9802, and an eighth metal protrusion 9808 may be provided at the other end of the signal line 9802. The fifth metal protrusion 940 and the seventh metal protrusion 9805 are arranged opposite to each other, the sixth metal protrusion 9208 and the eighth metal protrusion 9808 are arranged opposite to each other, and the sum of the thickness dimensions of the fifth metal protrusion 940 and the seventh metal protrusion 9805 in the Z-axis direction is equal to the sum of the thickness dimensions of the laser chip 920, the sixth metal protrusion 9208 and the eighth metal protrusion 9808 in the Z-axis direction.

[0137] When the adapter board 980 is placed upside down above the laser chip 920, the fifth metal protrusion 940 is welded to the seventh metal protrusion 9805, and the sixth metal protrusion 9208 is welded to the eighth metal protrusion 9808, so as to realize the signal connection among the substrate 910, the laser chip 920 and the adapter board 980, and thus transmit the electrical signal transmitted by the high-frequency signal line 9103 to the modulation electrode 9202 through the signal line 9802 on the adapter board 980, so that the modulation region of the laser chip 920 modulates the laser beam and the electrical signal.

[0138] In some embodiments, since the third power supply line 9110 on the substrate 910 is located above the high-frequency signal line 9103 ( Figure 14 the positive Y-axis direction shown), the dimension between the third power supply line 9110 and the laser chip 920 is smaller than the distance between the high-frequency signal line 9103 and the laser chip 920. Therefore, the length dimension of the conductive line 9801 in the Y-axis direction is smaller than the length dimension of the signal line 9802 in the Y-axis direction.

[0139] The adapter board 980 is placed upside down above the laser chip 920. The third power supply line 9110 on the substrate 910 is welded to the conductive wire 9801 on the adapter board 980. The conductive wire 9801 is welded to the light-emitting electrode 9201 of the laser chip 920. The high-frequency signal line 9103 on the substrate 910 is welded to the signal line 9802 on the adapter board 980. The signal line 9802 is welded to the modulation electrode 9202 of the laser chip 920, so as to transmit the bias current and the electrical signal to the laser chip 920 through the adapter board 980, enabling the laser chip 920 to generate a modulated optical signal.

[0140] The connection between the substrate 910 and the laser chip 920 is realized through the adapter board 980, avoiding the use of wire bonding, which can avoid the impedance mismatch problem caused by wire bonding, thereby improving the signal bandwidth of the laser chip 920.

[0141] In some embodiments, when the signal connection between the high-frequency signal line 9103 and the modulation electrode 9202 is realized through the adapter board 980, in order to realize signal return, the laser chip 920 needs to be connected to the ground conductive region 9100 on the substrate 910 through the adapter board 980 to realize the grounding of the laser chip 920.

[0142] Refer to Figure 11 、 Figure 12 and Figure 14 On the top surface of the laser chip 920, a grounding electrode is further provided. The grounding electrode is welded to the grounding conductive layer 9800 on the adapter board 980. A grounding post is provided on the ground conductive region 9100 of the substrate 910. The grounding conductive layer 9800 is welded to the grounding post, so as to realize the grounding connection between the laser chip 920 and the ground conductive region 9100 on the substrate 910 through the adapter board 980.

[0143] Refer to Figure 11 The grounding electrode on the laser chip 920 includes a first grounding electrode 9203 and a second grounding electrode 9204. The first grounding electrode 9203 and the second grounding electrode 9204 are located on both sides of the modulation electrode 9202. The first grounding electrode 9203, the modulation electrode 9202 and the second grounding electrode 9204 form a GSG (ground-signal-ground) mode.

[0144] In some embodiments, the first grounding electrode 9203 is located on the left side of the modulation electrode 9202 ( Figure 11 the left side shown), and there is a first distance L1 between the first grounding electrode 9203 and the modulation electrode 9202; the second grounding electrode 9204 is located on the right side of the modulation electrode 9202 ( Figure 11 the right side shown), and there is a second distance L2 between the second grounding electrode 9204 and the modulation electrode 9202. The first distance L1 is equal to the second distance L2.

[0145] Refer toFigure 10 To connect the first ground electrode 9203 to the second ground electrode 9204 and the ground conductive region 9100 on the substrate 910, a first ground post 950 and a second ground post 960 are provided on the ground conductive region 9100 of the substrate 910. The first ground post 950 and the second ground post 960 are located on the upper and lower sides of the high-frequency signal line 9103. A GSG mode is formed among the first ground post 950, the high-frequency signal line 9103, and the second ground post 960.

[0146] In some embodiments, the first ground post 950 is located on the second ground conductive region 9111, and the second ground post 960 is located on the third ground conductive region 9102.

[0147] Refer to Figure 14 , the adapter board 980 is placed upside down above the laser chip 920. The power supply line 9104 on the substrate 910 is welded to the conductive line 9801 on the adapter board 980. The conductive line 9801 is welded to the light-emitting electrode 9201 of the laser chip 920. The high-frequency signal line 9103 is welded to the signal line 9802 on the adapter board 980. The signal line 9802 is welded to the modulation electrode 9202 of the laser chip 920. The first ground electrode 9203 and the second ground electrode 9204 on the laser chip 920 are welded to the ground conductive layer 9800 on the adapter board 980. The ground conductive layer 9800 is welded to the first ground post 950 and the second ground post 960 on the substrate 910 to achieve signal grounding of the laser chip 920.

[0148] In some embodiments, when the thickness dimensions of the first ground post 950 and the second ground post 960 are less than or equal to the thickness dimension of the laser chip 920, the first ground electrode 9203 and the second ground electrode 9204 can be directly welded to the ground conductive layer 9800 on the adapter board 980, thereby achieving signal grounding of the laser chip 920.

[0149] Refer to Figure 11 , when the thickness dimensions of the first ground post 950 and the second ground post 960 are slightly greater than the thickness dimension of the laser chip 920, a third ground post 9207 is provided on the first ground electrode 9203, and a fourth ground post 9209 is provided on the second ground electrode 9204. The thickness dimensions of the first ground post 950 and the second ground post 960 are equal to the sum of the thickness dimensions of the laser chip 920, the third ground post 9207, and the fourth ground post 9209. The first ground electrode 9203 is welded to the ground conductive layer 9800 on the adapter board 980 through the third ground post 9207, and the second ground electrode 9204 is welded to the ground conductive layer 9800 through the fourth ground post 9209, thereby achieving signal grounding of the laser chip 920.

[0150] Refer to Figure 12, when the thickness dimensions of the first ground post 950 and the second ground post 960 are greater than the thickness dimension of the laser chip 920, a third ground post 9207 is provided on the first ground electrode 9203, a fourth ground post 9209 is provided on the second ground electrode 9204, a fifth ground post 9809 and a sixth ground post 9810 are provided on the ground conductive layer 9800 of the adapter board 980, the fifth ground post 9809 is welded to the third ground post 9207, and the sixth ground post 9810 is welded to the fourth ground post 9209, thereby realizing signal grounding of the laser chip 920.

[0151] In some embodiments, a third ground post 9207 is provided on the first ground electrode 9203, a fourth ground post 9209 is provided on the second ground electrode 9204, a fifth ground post 9809, a sixth ground post 9810, a seventh ground post 9806 and an eighth ground post 9807 are provided on the ground conductive layer 9800 of the adapter board 980, the third ground post 9207 is welded to the fifth ground post 9809, the fourth ground post 9209 is welded to the sixth ground post 9810, the first ground post 950 is welded to the seventh ground post 9806, and the second ground post 960 is welded to the eighth ground post 9807, thereby realizing signal grounding of the laser chip 920.

[0152] After the first ground electrode 9203 and the second ground electrode 9204 on the laser chip 920 are connected to the ground conductive region 9100 on the substrate 910 through the adapter board 980, ground wires are arranged on both sides of the high-frequency signal line, so that the transmission mode of the high-frequency electrical signal is the GSG mode, thereby being able to shorten the isolation between the electrical signal return path and the signal channel.

[0153] In some embodiments, since the RC parasitic parameters of the laser chip 920 itself have a great influence on the frequency response of the laser chip, for example, the parasitic capacitance of the laser chip 920 will cause the bandwidth of the laser chip to be low. In order to improve the signal bandwidth of the laser chip 920, a matching resistor can be added, and the matching resistor is arranged in parallel with the modulation region of the laser chip 920, so that the impedance output by the laser chip 920 is consistent with the characteristic impedance of the matching resistor.

[0154] Refer to Figure 12 , a second resistor 9811 is arranged in the fifth avoidance portion 9813 of the adapter board 980. The second resistor 9811 can be arranged along the positive Y-axis direction from the upper end of the signal line 9802. One end of the second resistor 9811 is connected to the signal line 9802, and the other end of the second resistor 9811 is connected to the ground conductive layer 9800, so that the other end of the second resistor 9811 is grounded, and the second resistor 9811 is connected in parallel with the laser chip 920. For the convenience of preparation, the second resistor 9811 has an impedance matching function, and finally the impedance output by the laser chip 920 is consistent with the characteristic impedance of the matching resistor.

[0155] In some embodiments, the second resistor 9811 may also be set at an angle on the adapter board 980, or may be set along the X-axis direction on the adapter board 980. As long as one end of the second resistor 9811 is connected to the signal line 9802 and the other end of the second resistor 9811 is connected to the ground conductive layer 9800, it all falls within the protection scope of the embodiments of the present disclosure.

[0156] In some embodiments, since the space of the adapter board 980 is relatively small, the second resistor 9811 is a thin film resistor that is sintered through an area of ​​the adapter board 980 .

[0157] In some embodiments, the power supply line 9104 on the substrate 910 is not limited to the layout described in the above embodiment, as long as the right end of the power supply line 9104 is welded to the conductive line 9801 on the adapter plate 980 , and the conductive line 9801 is welded to the light-emitting electrode 9201 .

[0158] Figure 15 A perspective view of the assembly of a substrate, a laser chip and an adapter plate in an optical module according to some embodiments of the present disclosure Figure 2 .like Figure 15 As shown, the ground conductive area 9100 on the substrate 910 includes a first ground conductive area 9101, a second ground conductive area 9111 and a third ground conductive area 9102, the first ground conductive area 9101, the second ground conductive area 9111 and the third ground conductive area 9102 are arranged along the Y-axis direction, and the laser chip 920 is mounted on the second ground conductive area 9111. In some embodiments, Figure 15 The X-axis direction shown is the left-right direction, and the Y-axis direction is the up-down direction.

[0159] The power supply line 9104 on the substrate 910 includes a first power supply line 9108, a second power supply line 9109 and a third power supply line 9110. The first power supply line 9108 extends from the left side of the substrate 910 along the positive direction of the X-axis, the second power supply line 9109 extends from the right end of the first power supply line 9108 along the positive direction of the Y-axis, and the third power supply line 9110 extends from the upper end of the second power supply line 9109 along the positive direction of the X-axis. The first power supply line 9108 and the second power supply line 9109 are located on the left side of the laser chip 920, and the third power supply line 9110 is located on the upper side of the laser chip 920. The first power supply line 9108, the second power supply line 9109 and the third power supply line 9110 form a Z-shaped power supply line.

[0160] The adapter plate 980 is flipped onto the laser chip 920. The upper end of the adapter plate 980 ( Figure 15The positive end of the Y-axis shown protrudes from the laser chip 920. The adapter board 980 covers the third power supply line 9110. A first metal protrusion 970 is provided on the third power supply line 9110. A conductive wire 9801 is provided on the adapter board 980. A third metal protrusion 9803 is provided at the upper end of the conductive wire 9801. A fourth metal protrusion 9804 is provided at the lower end of the conductive wire 9801. A second metal protrusion 9206 is provided on the light-emitting electrode 9201. The first metal protrusion 970 is welded to the third metal protrusion 9803, and the second metal protrusion 9206 is welded to the fourth metal protrusion 9804, so as to realize the power supply connection between the substrate 910 and the light-emitting area of the laser chip 920 through the adapter board 980, and enable the light-emitting area to generate a laser beam.

[0161] Figure 16 A partial connection between a circuit board and a laser chip in an optical module provided according to some embodiments of the present disclosure Figure 2 . As Figure 16 shown, the substrate 910 is mounted on the ceramic carrier 930, the laser chip 920 is mounted on the grounding conductive area 9100 of the substrate 910, the adapter board 980 is inverted and placed on the laser chip 920, and one end of the power supply line 9104 on the substrate 910 is welded to the conductive wire 9801 on the adapter board 980, and the conductive wire 9801 is welded to the light-emitting electrode 9201 of the laser chip 920; the other end of the power supply line 9104 is wire-bonded to the welding pad 305 on the circuit board 300, so as to transmit the bias current transmitted by the circuit board 300 to the light-emitting electrode 9201 via the power supply line 9104 and the conductive wire 9801, so as to provide a bias current to the light-emitting area of the laser chip 920, and enable the light-emitting area to generate a laser beam.

[0162] One end of the high-frequency signal line 9103 on the substrate 910 is welded to the signal line 9802 on the adapter board 980, and the signal line 9802 is welded to the modulation electrode 9202 of the laser chip 920; the other end of the high-frequency signal line 9103 is wire-bonded to the first differential signal line 302 on the circuit board 300, so as to transmit the current signal transmitted by the first differential signal line 302 to the modulation electrode 9202 via the high-frequency signal line 9103 and the signal line 9802, so as to provide a current signal to the modulation area of the laser chip 920, and enable the modulation area to modulate the laser beam and the current signal to obtain a modulated optical signal.

[0163] The first grounding electrode 9203 and the second grounding electrode 9204 on the laser chip 920 are welded to the grounding conductive layer 9800 on the adapter board 980. The grounding conductive layer 9800 is welded to the grounding conductive area 9100 on the substrate 910. The grounding conductive area 9100 is wire-bonded to the first grounding pad 305 and the second grounding pad 306 on the circuit board 300, so as to realize the signal grounding of the laser chip 920.

[0164] Wire-bond the second differential signal line 303 on the circuit board 300 to the resistance pad 9106 on the substrate 910. The resistance pad 9106 is connected to the first resistor 9107, and the first resistor 9107 is connected to the ground conductive region 9100 to achieve impedance matching of the laser chip 920.

[0165] In the optical module provided by the embodiments of the present disclosure, an adapter board is added in the optical emission component 400. The substrate is mounted on a ceramic carrier. The substrate is connected to the circuit board by wire bonding. The laser chip is mounted on the substrate. The adapter board is placed on the laser chip in a flip-chip manner to realize the electrical connection between the laser chip and the substrate, so as to replace the wire bonding for connecting the laser chip and the substrate currently, and can avoid the impedance mismatch problem caused by wire bonding; ground electrodes are arranged on both sides of the modulation electrode on the laser chip. The modulated electrical signal and GND form a GSG mode, and the modulation electrode and the ground electrode are on the same plane, so that the return path of the modulated electrical signal and the isolation between signal channels can be shortened, and thus the signal bandwidth can be effectively increased.

[0166] After the electrical connection between the laser chip 920, the adapter board 980, the substrate 910 and the circuit board 300 is realized, the light-emitting region in the laser chip 920 generates a laser beam under the action of the bias current. The laser beam is transmitted to the modulation region through the optical waveguide layer in the laser chip 920. The modulation region modulates the current signal and the laser beam to obtain a modulated optical signal, and the modulated optical signal is emitted through the optical waveguide layer.

[0167] With the rapid development of application markets such as big data, cloud computing, and artificial intelligence, the demand for data communication optical modules is also increasing rapidly. The optical device industry is continuously evolving towards meeting higher data rates, lower power consumption, lower costs, etc. As a key device in optical communication, the semiconductor laser chip faces higher challenges, and the demand for laser chips is gradually replacing from 10G to 56G and 100G.

[0168] Figure 17 For the structure of a laser chip in an optical module provided by some embodiments of the present disclosure Figure 2 As Figure 17As shown in the figure, the EML laser chip includes a Distributed Feedback Laser (DFB) light source (i.e., the light-emitting region) 9210, an Electro Absorption Modulator (EAM) 9211, and a first optical waveguide 9212 connecting the DFB light source 9210 and the EAM modulator 9211. The DFB light source 9210 generates a laser beam under the action of a bias current. The laser beam is transmitted to the EAM modulator 9211 through the first optical waveguide 9212. The EAM modulator 9211 receives a current signal from the circuit board 300 through a modulation electrode 9202. The EAM modulator 9211 modulates the current signal and the laser beam to obtain a modulated light, and the modulated light is emitted through the first optical waveguide 9212.

[0169] The DFB light source 9210 and the EAM modulator 9211 can be designed independently. The light source part can improve the photoelectric conversion efficiency and output power of the laser chip by means of reducing the number of QWs, increasing the gain area, etc. Since there is no resonant optical field in the modulator part, the interaction between photons and electrons in the laser chip during high-speed modulation is avoided, and a modulation rate of 100 Gbaud and above can be achieved.

[0170] In order to meet the requirements of working at a higher speed, it is necessary to reduce the capacitance of the EAM to improve the modulation rate. Reducing the capacitance to improve the modulation rate can be achieved by reducing the cavity length, ridge width, and increasing the thickness of the active layer, etc. However, adopting this scheme will lead to the deterioration of the far-field performance. For example, reducing the cavity length and ridge width will cause the optical confinement factor of the Quantum Wells (QWs) to decrease, resulting in an overly small near-field spot of the light emitted by the laser chip and an overly small far-field divergence angle of the emitted light.

[0171] Figure 18a It is a structural diagram of a deeply etched waveguide in an optical module according to some embodiments of the present disclosure. Figure 18b It is a mode spot schematic diagram of an optical waveguide in an optical module according to some embodiments of the present disclosure. Figure 18c It is a lateral divergence angle curve of a laser chip in an optical module according to some embodiments of the present disclosure. Figure 1 , Figure 18d It is a longitudinal divergence angle curve of a laser chip in an optical module according to some embodiments of the present disclosure. Figure 1 . As Figure 18a - 18dAs shown, in a laser chip with a higher modulation rate (such as 100 Gbaud and above), the first optical waveguide 9212 often adopts a deeply etched optical waveguide. By increasing the transverse confinement of the optical field by the deeply etched optical waveguide, and then reducing the ridge width on top of the deeply etched waveguide, the transverse size of the mode spot in the optical waveguide is further reduced, resulting in a smaller near-field mode spot of light. Under the diffraction effect, the smaller the near-field mode spot, the larger the far-field divergence angle.

[0172] Referring to Figure 18c With Figure 18d , when the width of the deeply etched optical waveguide is typically 1.2 μm, the far-field divergence angle of the laser chip 920 is 30°×46°.

[0173] The optical coupling from the laser chip 920 to the optical fiber often first focuses the light into the optical fiber through a lens. An overly large far-field divergence angle of the EML laser chip or a too large difference in the divergence angles in the transverse and longitudinal directions will result in a lower coupling efficiency between the laser chip and the optical fiber. For example, an overly large far-field divergence angle of the laser chip 920 will cause some of the optical field emitted by the laser chip to exceed the collection range of the lens; different divergence angles in the transverse and longitudinal directions will introduce astigmatism in the optical path, causing the focal lengths of the light in the two directions to be in different planes after passing through the lens, thereby reducing the optical fiber coupling efficiency. Therefore, improving the near-field spot shape and far-field divergence angle of the EML laser chip is crucial for the application of the EML laser chip.

[0174] To increase the modulation rate of the EML laser chip, the first optical waveguide 9212 connecting the DFB light source 9210 and the EAM modulator 9211 adopts a deeply etched optical waveguide, and the number of QWs is increased to ensure the modulation rate, but this will sacrifice the far-field divergence angle. Compared with the deeply etched optical waveguide, the effective refractive index difference between the waveguide core layer and the two side claddings of the buried heterojunction (BH) waveguide is smaller, resulting in a smaller confinement effect of the BH waveguide on the optical field. Therefore, the near-field mode spot of light transmitted by the BH waveguide is larger, and the corresponding far-field divergence angle is smaller.

[0175] Figure 19 The structure of a laser chip in an optical module according to some embodiments of the present disclosure Figure 3 , Figure 20 A partial top view of a laser chip in an optical module according to some embodiments of the present disclosure. As Figure 19 With Figure 20As shown in the figure, in order to improve the far-field divergence angle of the EML laser chip, the optical waveguide of the laser chip 920 includes a first optical waveguide 9212 and a second optical waveguide 9214. The first optical waveguide 9212 connects the DFB light source 9210 and the EAM modulator 9211. The light input end of the second optical waveguide 9214 is coupled to the light output end of the first optical waveguide 9212. The first optical waveguide 9212 is a deeply etched optical waveguide, and the second optical waveguide 9214 is a buried heterostructure optical waveguide. The modulated light output by the deeply etched optical waveguide is transmitted into the buried heterostructure optical waveguide. Since the effective refractive index difference between the waveguide core layer and the cladding in the buried heterostructure optical waveguide is small, the confinement effect of the buried heterostructure optical waveguide on the optical field is small, resulting in a relatively large near-field mode spot and a relatively small far-field divergence angle. Therefore, by butt-joining the buried heterostructure optical waveguide at the light output end of the deeply etched optical waveguide, the far-field divergence angle is optimized.

[0176] When directly performing end-face coupling between the deeply etched optical waveguide and the buried heterostructure optical waveguide, due to the mismatch of the mode fields between the deeply etched optical waveguide and the buried heterostructure optical waveguide, the effective refractive index differences of the deeply etched optical waveguide and the buried heterostructure optical waveguide are different (the effective refractive index difference of the deeply etched optical waveguide is large, and the effective refractive index difference of the buried heterostructure optical waveguide is small), which easily causes light to be reflected at the coupling end face between the deeply etched optical waveguide and the buried heterostructure optical waveguide, affecting the light transmittance and thus the light coupling efficiency.

[0177] To avoid light reflection at the coupling end face between the deeply etched optical waveguide and the buried heterostructure optical waveguide, the optical waveguide of the laser chip 920 further includes a third optical waveguide 9213. The third optical waveguide 9213 is a transition optical waveguide. The light input end of the third optical waveguide 9213 is mode-matched with the light output end of the first optical waveguide 9212, and the light input end of the third optical waveguide 9213 is coupled to the light output end of the first optical waveguide 9212. The light output end of the third optical waveguide 9213 is mode-matched with the light input end of the second optical waveguide 9214, and the light output end of the third optical waveguide 9213 is coupled to the light input end of the second optical waveguide 9214, so as to realize the transition connection between the first optical waveguide 9212 and the second optical waveguide 9214 through the third optical waveguide 9213 and improve the light transmittance between the first optical waveguide 9212 and the second optical waveguide 9214 through the third optical waveguide 9213.

[0178] Figure 21 It is a top view of a partial structure of a laser chip in an optical module provided according to some embodiments of the present disclosure. Figure 22 It is a waveguide structure diagram of a laser chip in an optical module provided according to some embodiments of the present disclosure. Figure 23a is Figure 21 the cross-sectional view taken along line A-A in Figure 21 、 Figure 22 and Figure 23aAs shown, the first optical waveguide 9212 is a deeply etched optical waveguide. The first optical waveguide 9212 includes a first waveguide core layer 9221, a first cladding layer 9222, and a second cladding layer 9223. The first cladding layer 9222 is disposed on the substrate layer 9220 of the laser chip 920 along the epitaxial growth direction. The first waveguide core layer 9221 is disposed on the first cladding layer 9222 along the epitaxial growth direction. The second cladding layer 9223 is disposed on the first waveguide core layer 9221 along the epitaxial growth direction, so as to surround the first waveguide core layer 9221 through the first cladding layer 9222 and the second cladding layer 9223.

[0179] In some embodiments, the substrate layer 9220 may be an N-type InP substrate layer, the first cladding layer 9222 may be a P-type InP layer, the second cladding layer 9223 may be a P-type InP layer, and the first waveguide core layer 9221 may be an InGaAsP core layer.

[0180] In some embodiments, the effective refractive index of the first waveguide core layer 9221 is greater than that of the first cladding layer 9222. The effective refractive index of the first cladding layer 9222 may be the same as that of the second cladding layer 9223. There is a first effective refractive index difference between the effective refractive index of the first waveguide core layer 9221 and the effective refractive indices of the first cladding layer 9222 and the second cladding layer 9223. The signal light transmitted by the first waveguide core layer 9221 is reflected at the first cladding layer 9222 and the second cladding layer 9223, so as to constrain and limit the optical field transmitted by the first waveguide core layer 9221.

[0181] In order to transmit the modulated light output by the EAM modulator 9211, the first waveguide core layer 9221 of the first optical waveguide 9212 has a first width W1 and a first thickness H1. In this way, the modulated light output by the EAM modulator 9211 is transmitted within the first waveguide core layer 9221, and the modulated light is reflected at the first cladding layer 9222 and the second cladding layer 9223, so as to improve the light transmittance.

[0182] In some embodiments, the size of the first width W1 is 1 - 2 μm, and the size of the first thickness H1 is 150 - 300 nm.

[0183] In some embodiments, the size of the first width W1 is 2 μm, and the size of the first thickness H1 is 300 nm.

[0184] The width size of the first cladding layer 9222 may be equal to the width size of the second cladding layer 9223, and the width size of the first cladding layer 9222 may be equal to the width size of the first waveguide core layer 9221. The thickness size of the first cladding layer 9222 may be equal to the thickness size of the second cladding layer 9223, and the thickness size of the first cladding layer 9222 may be greater than the thickness size of the first waveguide core layer 9221. In some embodiments, the thickness size of the first cladding layer 9222 may be 1.5 - 2 μm.

[0185] Since the first optical waveguide 9212 is coupled to the EAM modulator 9211, the EAM modulator 9211 includes a substrate layer, an active layer, a waveguide layer, an electrode layer, etc. Buried layers are provided on both sides of the active layer to block electrons on both sides of the active layer. The first waveguide core layer 9221 of the first optical waveguide 9212 is coupled to the active layer of the EAM modulator 9211. To transmit the light of the active layer to the first waveguide core layer 9221, the material of the first waveguide core layer 9221 is different from that of the active layer of the EAM modulator 9211, so that the effective refractive index of the first waveguide core layer 9221 is greater than that of the active layer.

[0186] In some embodiments, the material of the first waveguide core layer 9221 is InGaAsP, and the material of the active layer of the EAM modulator 9211 is an Al-containing material, for example, InAlGaAs.

[0187] Since buried regions are provided on both sides of the active layer in the EAM modulator 9211 and the first waveguide core layer 9221 is coupled to the active layer, thus, first buried region 9224 and second buried region 9225 can also be provided on both sides of the first waveguide core layer 9221. The first buried region 9224 and the second buried region 9225 are located on both sides of the first waveguide core layer 9221, and the first buried region 9224 and the second buried region 9225 surround the first waveguide core layer 9221 to protect the first waveguide core layer 9221 through the first buried region 9224 and the second buried region 9225. In some embodiments, the first buried region 9224 and the second buried region 9225 are SiO2.

[0188] In some embodiments, the first buried region 9224 and the second buried region 9225 are provided on the substrate layer 9220 along the epitaxial growth direction, and the top surfaces of the first buried region 9224 and the second buried region 9225 can be flush with the top surface of the second cladding layer 9223.

[0189] Figure 23b For Figure 21 Cross-sectional view at C-C. As Figure 22 And Figure 23b As shown, the second optical waveguide 9214 includes a second waveguide core layer 9226, a first cladding layer 9222 and a second cladding layer 9223. The first cladding layer 9222 is provided on the substrate layer 9220 along the epitaxial growth direction, the second waveguide core layer 9226 is provided on the first cladding layer 9222 along the epitaxial growth direction, and the second cladding layer 9223 is provided on the second waveguide core layer 9226 along the epitaxial growth direction to surround the second waveguide core layer 9226 through the first cladding layer 9222 and the second cladding layer 9223.

[0190] In some embodiments, the substrate layer 9220 may be an N-type InP substrate layer, the first cladding layer 9222 may be a P-type InP layer, the second cladding layer 9223 may be a P-type InP layer, and the second waveguide core layer 9226 may be an InGaAsP core layer.

[0191] In some embodiments, the first cladding layer of the second optical waveguide 9214 and the first cladding layer of the first optical waveguide 9212 may be the same cladding layer, and the second cladding layer of the second optical waveguide 9214 and the second cladding layer of the first optical waveguide 9212 may be the same cladding layer.

[0192] In some embodiments, the effective refractive index of the second waveguide core layer 9226 is less than the effective refractive index of the first waveguide core layer 9221, the effective refractive index of the second waveguide core layer 9226 is greater than the effective refractive index of the first cladding layer 9222, the effective refractive index of the first cladding layer 9222 may be the same as the effective refractive index of the second cladding layer 9223, and there is a second effective refractive index difference between the effective refractive index of the second waveguide core layer 9226 and the effective refractive indices of the first cladding layer 9222 and the second cladding layer 9223, so that the first cladding layer 9222 and the second cladding layer 9223 can constrain and limit the optical field transmitted by the second waveguide core layer 9226.

[0193] Since the effective refractive index of the second waveguide core layer 9226 is less than the effective refractive index of the first waveguide core layer 9221, the second effective refractive index difference of the second optical waveguide 9214 is less than the first effective refractive index difference of the first optical waveguide 9212. Thus, compared with the first optical waveguide 9212, the second optical waveguide 9214 has a smaller limiting effect on the optical field it transmits, the near-field mode spot of the light output by the second optical waveguide 9214 is larger, and the corresponding far-field divergence angle is smaller, thereby optimizing the near-field spot shape and the far-field divergence angle through the second optical waveguide 9214.

[0194] In some embodiments, the second waveguide core layer 9226 and the first waveguide core layer 9221 are made of the same material. Since the effective refractive index of the waveguide core layer is positively correlated with the width of the waveguide core layer, in order to reduce the effective refractive index of the second waveguide core layer 9226, compared with the first waveguide core layer 9221, the width dimension of the second waveguide core layer 9226 can be reduced.

[0195] The second waveguide core layer 9226 has a second width W2, and the second width W2 is less than the first width W1, thereby reducing the effective refractive index of the second waveguide core layer 9226, making the second effective refractive index difference of the second optical waveguide 9214 less than the first effective refractive index difference of the first optical waveguide 9212, so as to reduce the far-field divergence angle of the optical field transmitted by the second optical waveguide 9214.

[0196] In some embodiments, since the smaller the core layer thickness of the optical waveguide, the smaller the confinement of the optical waveguide to the optical field and the larger the near-field light spot. Thus, the second waveguide core layer 9226 has a second thickness H2, and the second thickness H2 is less than the first thickness H1 to reduce the overall size of the second waveguide core layer 9226, so that the confinement of the second waveguide core layer 9226 to the optical field is reduced, thereby reducing the far-field divergence angle of the optical field transmitted by the second optical waveguide 9214.

[0197] In some embodiments, the size of the second width W2 is 0.5 - 2 nm, and the size of the second thickness H2 is 150 - 300 nm.

[0198] In some embodiments, the size of the second width W2 is 2 nm, and the size of the second thickness H2 is 150 nm.

[0199] Since the width dimension W1 of the first waveguide core layer 9221 is greater than the width dimension W2 of the second waveguide core layer 9226, the cross-sectional dimensions of the first optical waveguide 9212 and the second optical waveguide 9214 are different. When the signal light is coupled between the first optical waveguide 9212, the third optical waveguide 9213 and the second optical waveguide 9214, due to the difference in the cross-sections of the optical waveguides, there will be a sudden change in the optical transmission mode, thus causing loss. Therefore, the third optical waveguide 9213 is set as a tapered optical waveguide to achieve the transition of the cross-sectional dimensions between the first optical waveguide 9212 and the second optical waveguide 9214 through the third optical waveguide 9213.

[0200] Refer to Figure 22 , along the light emission direction, the third optical waveguide 9213 has a length L. The third optical waveguide 9213 includes a first tapered optical waveguide 9215 and a second tapered optical waveguide 9216. The light incident end of the first tapered optical waveguide 9215 is coupled to the light output end of the first optical waveguide 9212, the light output end of the first tapered optical waveguide 9215 is coupled to the light incident end of the second tapered optical waveguide 9216, and the light output end of the second tapered optical waveguide 9216 is coupled to the light incident end of the second optical waveguide 9214.

[0201] In some embodiments, the mode fields of the first optical waveguide 9212, the first tapered optical waveguide 9215, the second tapered optical waveguide 9216 and the second optical waveguide 9214 are matched to smoothly transmit the signal light transmitted by the first optical waveguide 9212 to the second optical waveguide 9214 through the first tapered optical waveguide 9215 and the second tapered optical waveguide 9216 and ensure the light transmittance.

[0202] In some embodiments, the width dimension of the light-incident end of the first tapered optical waveguide 9215 may be equal to the width dimension of the first optical waveguide 9212. Along the light emission direction, the width dimension of the first tapered optical waveguide 9215 gradually increases, such that the width dimension of the end of the first tapered optical waveguide 9215 is greater than the width dimension of the first optical waveguide 9212. Thus, the effective refractive index of the waveguide core layer of the first tapered optical waveguide 9215 is greater than the effective refractive index of the first waveguide core layer 9221, so as to facilitate coupling the signal light transmitted by the first optical waveguide 9212 to the third optical waveguide 9213.

[0203] Along the light emission direction, the width dimension of the second tapered optical waveguide 9216 gradually decreases, and the width dimension of the light-emitting end of the second tapered optical waveguide 9216 may be equal to the width dimension of the second optical waveguide 9214. Thus, the effective refractive index of the second tapered optical waveguide 9216 is greater than the effective refractive index of the second waveguide core layer 9226, and the confinement effect of the second waveguide core layer 9226 on the optical field is less than the confinement effect of the second tapered optical waveguide 9216 on the optical field, such that the signal light transmitted by the first tapered optical waveguide 9215 is slowly transmitted to the second optical waveguide 9214 via the second tapered optical waveguide 9216 without causing light reflection and loss.

[0204] Figure 23c For Figure 21 the cross-sectional view taken along C-C in Figure 23c As shown, the first tapered optical waveguide 9215 and the second tapered optical waveguide 9216 have the same structural composition. The second tapered optical waveguide 9216 includes a third waveguide core layer 9227, a first cladding layer 9222, and a second cladding layer 9223. The first cladding layer 9222 is disposed on the substrate layer 9220 along the epitaxial growth direction, the third waveguide core layer 9227 is disposed on the first cladding layer 9222 along the epitaxial growth direction, and the second cladding layer 9223 is disposed on the third waveguide core layer 9227 along the epitaxial growth direction to surround the third waveguide core layer 9227 through the first cladding layer 9222 and the second cladding layer 9223.

[0205] In some embodiments, the substrate layer 9220 may be an N-type InP substrate layer, the first cladding layer 9222 may be a P-type InP layer, the second cladding layer 9223 may be a P-type InP layer, and the third waveguide core layer 9227 may be an InGaAsP core layer.

[0206] In some embodiments, the first cladding layer of the third optical waveguide 9213 and the first cladding layer of the first optical waveguide 9212 may be the same cladding layer, and the second cladding layer of the third optical waveguide 9213 and the second cladding layer of the first optical waveguide 9212 may be the same cladding layer.

[0207] The effective refractive index of the third waveguide core layer 9227 can be less than that of the first waveguide core layer 9221, and the effective refractive index of the third waveguide core layer 9227 is greater than that of the first cladding layer 9222. The effective refractive index of the first cladding layer 9222 can be the same as that of the second cladding layer 9223. There is a third effective refractive index difference between the effective refractive index of the third waveguide core layer 9227 and those of the first cladding layer 9222 and the second cladding layer 9223, so that the first cladding layer 9222 and the second cladding layer 9223 can constrain and limit the optical field transmitted by the third waveguide core layer 9227.

[0208] The third effective refractive index difference of the third optical waveguide 9213 is less than the first effective refractive index difference of the first optical waveguide 9212, and the second effective refractive index difference of the second optical waveguide 9214 is less than the third effective refractive index difference of the third optical waveguide 9213. In this way, when light is transmitted along the first optical waveguide 9212, the third optical waveguide 9213, and the second optical waveguide 9214, the confinement effect on the optical field gradually decreases, so that no reflection and loss are caused when light is transmitted in the third optical waveguide 9213.

[0209] Refer to Figure 23c To achieve the transitional connection between the first optical waveguide 9212 and the second optical waveguide 9214 through the third optical waveguide 9213, the third waveguide core layer 9227 has a third width W3 and a third thickness H3. The size of the third width W3 can be greater than the first width W1 of the first waveguide core layer 9221, the size of the third thickness H3 can be equal to the first thickness H1 of the first waveguide core layer 9221, the size of the third width W3 is greater than the second width W2 of the second waveguide core layer 9226, and the size of the third thickness H3 can be greater than the second thickness H2 of the second waveguide core layer 9226.

[0210] In some embodiments, the size of the third width W3 is 1.1 - 2.5 μm, and the size of the third thickness H3 is 150 - 300 nm.

[0211] In some embodiments, the size of the third width W3 is 2.5 μm, and the size of the third thickness H3 is 300 m.

[0212] Refer to Figure 21 To achieve a smooth transition from the first optical waveguide 9212 to the second optical waveguide 9214, a third optical waveguide 9213 is formed on the laser chip 920. When fabricating the third optical waveguide 9213, lithography is first performed along the first lithography line, and the mesa structure of the second optical waveguide 9214 is etched, and the top layer is epitaxially grown to facilitate the coupling connection between the light output end of the third optical waveguide 9213 and the second optical waveguide 9214. Then, lithography is performed along the second lithography line, and the ridge structure of the first optical waveguide 9212 is etched to facilitate the coupling connection between the light input end of the third optical waveguide 9213 and the light output end of the first optical waveguide 9212.

[0213] When fabricating the laser chip 920, after growing structures such as an active layer, a waveguide layer, an electrode layer, and a buried layer on a substrate layer, lithography is performed to obtain a first optical waveguide (deep-etched optical waveguide) 9212 and a second optical waveguide (buried heterojunction optical waveguide) 9214. Then, the first optical waveguide 9212 and the second optical waveguide 9214 are etched along a first lithography line and a second lithography line to obtain a third optical waveguide 9213, so as to achieve a smooth transition from the deep-etched optical waveguide (the first optical waveguide 9212) to the shallow-etched optical waveguide (the second optical waveguide 9214) through the third optical waveguide 9213, and light will not cause reflection and loss when transmitting in the third optical waveguide 9213.

[0214] Since the third optical waveguide 9213 results from two lithographies, there may be an alignment deviation between the first optical waveguide 9212, the third optical waveguide 9213, and the second optical waveguide 9214. This alignment deviation may cause the transmittance of the light transmitted by the first optical waveguide 9212, the third optical waveguide 9213, and the second optical waveguide 9214, thereby affecting the optical coupling efficiency.

[0215] Figure 24a The transmittance relationship of the transition optical waveguide in an optical module provided according to some embodiments of the present disclosure Figure 1 , Figure 24b The transmittance relationship of the transition optical waveguide in an optical module provided according to some embodiments of the present disclosure Figure 2 , Figure 24c The transmittance relationship of the transition optical waveguide in an optical module provided according to some embodiments of the present disclosure Figure 3 。As Figure 24a 、 Figure 24b And Figure 24c shown, a first optical waveguide 9212, a third optical waveguide 9213, and a second optical waveguide 9214 are sequentially arranged on the laser chip 920 along the light emission direction. The first optical waveguide 9212 is coupled to the DFB light source 9210 of the laser chip 920, and the first optical waveguide 9212 is coupled to the EAM modulator 9211 of the laser chip 920. The light beam generated by the DFB light source 9210 is transmitted to the EAM modulator 9211 through the first optical waveguide 9212. After the EAM modulator 9211 modulates the light beam to obtain modulated light, the modulated light is coupled into the third optical waveguide 9213 through the first optical waveguide 9212, and the third optical waveguide 9213 couples the modulated light to the second optical waveguide 9214.

[0216] Refer to Figure 24a, when achieving a smooth transition from the first optical waveguide 9212 to the second optical waveguide 9214 through the third optical waveguide 9213 without causing reflection and loss, it is detected that as the length dimension L of the third optical waveguide 9213 increases, the optical coupling transmittance of the first optical waveguide 9212 through the third optical waveguide 9213 to the second optical waveguide 9214 gradually increases. Then, when the optical transmittance of the third optical waveguide 9213 reaches a certain node, the optical transmittance of the third optical waveguide 9213 no longer increases with the increase of the length dimension L. Therefore, the optical transmittance can be optimized by adjusting the length dimension L of the third optical waveguide 9213.

[0217] In some embodiments, the length dimension L of the third optical waveguide 9213 is 30 - 150 μm to improve the optical transmittance between the first optical waveguide 9212, the third optical waveguide 9213, and the second optical waveguide 9214.

[0218] In some embodiments, the length dimension L of the third optical waveguide 9213 is 50 - 100 μm to optimize the optical transmittance between the first optical waveguide 9212, the third optical waveguide 9213, and the second optical waveguide 9214.

[0219] In some embodiments, the length dimension L of the third optical waveguide 9213 is 100 μm to ensure the optical transmittance between the first optical waveguide 9212, the third optical waveguide 9213, and the second optical waveguide 9214.

[0220] Since the third optical waveguide 9213 includes a first tapered optical waveguide 9215 and a second tapered optical waveguide 9216, along the light emission direction, the width dimension of the first tapered optical waveguide 9215 gradually increases, and the width dimension of the second tapered optical waveguide 9216 gradually decreases. To optimize the optical transmittance of the third optical waveguide 9213, the length dimension ratio between the first tapered optical waveguide 9215 and the second tapered optical waveguide 9216 is not limited, as long as the length dimension of the third optical waveguide 9213 satisfies 50 - 100 μm.

[0221] Refer to Figure 24b , when achieving a smooth transition from the first optical waveguide 9212 to the second optical waveguide 9214 through the third optical waveguide 9213 without causing reflection and loss, it is detected that as the width dimensions of the first optical waveguide 9212, the third optical waveguide 9213, and the second optical waveguide 9214 increase, the optical coupling transmittance of the first optical waveguide 9212 through the third optical waveguide 9213 to the second optical waveguide 9214 gradually increases. Then, when the optical transmittance of the third optical waveguide 9213 reaches a certain node, the optical transmittance of the third optical waveguide 9213 no longer increases with the increase of the width dimensions of the optical waveguides. Therefore, the optical transmittance can be optimized by adjusting the width dimensions of the first optical waveguide 9212, the third optical waveguide 9213, and the second optical waveguide 9214.

[0222] In some embodiments, the first width W1 of the first waveguide core layer 9221 in the first optical waveguide 9212 needs to satisfy 1 - 2 μm, the second width W2 of the second waveguide core layer 9226 in the second optical waveguide 9214 needs to satisfy 0.5 - 2 nm, and the third width W3 of the third waveguide core layer 9227 in the third optical waveguide 9213 needs to satisfy 1.1 - 2.5 μm, so as to optimize the light transmittance between the first optical waveguide 9212, the third optical waveguide 9213 and the second optical waveguide 9214.

[0223] In some embodiments, the size of the first width W1 is 2 μm, the size of the second width W2 is 2 nm, and the size of the third width W3 is 2.5 μm.

[0224] Refer to Figure 24c , the third optical waveguide 9213 is obtained by performing photolithography twice on the optical waveguide on the laser chip 920. The alignment deviation between the first optical waveguide 9212, the third optical waveguide 9213 and the second optical waveguide 9214 is negatively correlated with the light transmittance. To optimize the light transmittance, the width size of the first optical waveguide 9212 is set to 2 μm, the width size of the second optical waveguide 9214 is set to 2 nm, the maximum width size of the third optical waveguide 9213 is set to 2.5 μm, and the length size of the third optical waveguide 9213 is set to 100 μm. In this way, the alignment deviation between the first optical waveguide 9212, the third optical waveguide 9213 and the second optical waveguide 9214 can be optimized, thereby optimizing the light transmittance.

[0225] Figure 25a For the simulation result of the overall far - field morphology of the laser chip in an optical module provided by some embodiments of the present disclosure Figure 1 , Figure 25b For the simulation result of the overall far - field morphology of the laser chip in an optical module provided by some embodiments of the present disclosure Figure 2 , Figure 25c For the lateral divergence angle curve of the laser chip in an optical module provided by some embodiments of the present disclosure Figure 2 , Figure 25d For the longitudinal divergence angle curve of the laser chip in an optical module provided by some embodiments of the present disclosure Figure 2 . Such as Figure 25a - Figure 25dAs shown in the figure, a third optical waveguide 9213 and a second optical waveguide 9214 are added to the output end of the first optical waveguide 9212 in the laser chip 920. The second optical waveguide 9214 is coupled to the first optical waveguide 9212 through the third optical waveguide 9213. Through the third optical waveguide 9213, a smooth transition between the first optical waveguide 9212 and the second optical waveguide 9214 is achieved without causing optical reflection and loss, thereby realizing the coupling connection between the first optical waveguide 9212 and the second optical waveguide 9214, reducing the end-face reflection of light, and improving the optical coupling efficiency.

[0226] Since the first optical waveguide 9212 is a deeply etched optical waveguide and the second optical waveguide 9214 is a buried heterostructure optical waveguide, the width of the second waveguide core layer 9226 of the second optical waveguide 9214 is smaller than the width of the first waveguide core layer 9221 of the first optical waveguide 9212, and the thickness of the second waveguide core layer 9226 is smaller than the thickness of the first waveguide core layer 9221. Compared with the first optical waveguide 9212, the effective refractive index difference between the waveguide core of the second optical waveguide 9214 and the cladding on both sides is smaller, and the confinement effect of the second optical waveguide 9214 on the optical field it transmits is smaller. Therefore, the near-field mode spot of the light transmitted by the second optical waveguide 9214 is larger, and the corresponding far-field divergence angle is smaller.

[0227] By setting a buried heterostructure optical waveguide on the laser chip 920 and adjusting the thickness and width of the waveguide core layer in the buried heterostructure optical waveguide to reduce the effective refractive index difference of the buried heterostructure optical waveguide, the near-field mode spot size of the light output from the buried heterostructure optical waveguide is increased, and the far-field divergence angle of the light output from the buried heterostructure optical waveguide is reduced. Finally, it can be realized that the near-field mode spot of the light output from the buried heterostructure optical waveguide is approximately circular, the ratio of the transverse divergence angle to the longitudinal divergence angle is close to 1:1, and the full width at half maxima (FWHM) of the divergence angle is less than 30°.

[0228] In the EML laser chip with a rate of 100 Gbaud and above provided by the embodiments of the present disclosure, in order to improve the modulation rate, the EAM modulator needs to adopt a deeply etched waveguide structure and increase the number of quantum wells (QWs) to ensure the modulation rate, but it will sacrifice the far-field divergence angle of light, resulting in a low coupling efficiency between the EML laser chip and the optical fiber. The present disclosure additionally docks a section of transition optical waveguide and a buried heterostructure optical waveguide behind the deeply etched optical waveguide of the EAM modulator, realizes the coupling connection between the deeply etched optical waveguide and the buried heterostructure optical waveguide through the transition optical waveguide, optimizes the near-field mode spot size and far-field divergence angle of the EML laser chip through the buried heterostructure optical waveguide while ensuring the high transmittance of light, and improves the coupling efficiency between the EML laser chip and the optical fiber, thereby realizing the preparation of an ultra-high-speed EML laser chip.

[0229] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present disclosure, rather than to limit them; although the present disclosure has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present disclosure.

Claims

1. An optical module, characterized in that, Comprising: A circuit board, on which driving signal lines, power supply pads and ground pads are provided; An optical emission component, electrically connected to the circuit board, the optical emission component being used for generating and outputting an optical signal; wherein, the optical emission component includes: A substrate, on which a ground conductive region, a power supply line and a high-frequency signal line are provided, the power supply line is not connected to the high-frequency signal line and the ground conductive region, the ground conductive region is wire-bonded to the ground pad, one end of the power supply line is wire-bonded to the power supply pad, and one end of the high-frequency signal line is wire-bonded to the driving signal line; A laser chip, mounted on the substrate, the laser chip includes a light-emitting region and a modulation region, a light-emitting electrode and a modulation electrode are provided on the top surface of the laser chip, the light-emitting electrode is connected to the light-emitting region, and the modulation electrode is connected to the modulation region; An adapter board, mounted on the laser chip, a ground conductive layer, a conductive wire and a signal line are provided on the side surface of the adapter board facing the substrate, the conductive wire is not connected to the signal line and the ground conductive layer, one end of the conductive wire is welded to the light-emitting electrode, and the other end of the conductive wire is welded to the other end of the power supply line to transmit a bias current to the light-emitting region; one end of the signal line is welded to the modulation electrode, and the other end of the signal line is welded to the other end of the high-frequency signal line to transmit a current signal to the modulation region.

2. The optical module according to claim 1, characterized in that, A second resistor is further provided on the side surface of the adapter board facing the substrate, one end of the second resistor is connected to the signal line, and the other end of the second resistor is connected to the ground conductive layer.

3. The optical module according to claim 1, characterized in that, A first metal protrusion is provided on the power supply line, the first metal protrusion protrudes from the substrate, and the first metal protrusion is welded to the conductive wire; A fifth metal protrusion is provided on the high-frequency signal line, the fifth metal protrusion protrudes from the substrate, and the fifth metal protrusion is welded to the signal line.

4. The optical module according to claim 3, characterized in that, A first ground electrode and a second ground electrode are provided on the top surface of the laser chip, the first ground electrode and the second ground electrode are located on both sides of the modulation electrode, and the distance between the first ground electrode and the modulation electrode is equal to the distance between the second ground electrode and the modulation electrode; The first ground electrode and the second ground electrode are welded to the ground conductive layer, and the ground conductive layer is welded to the ground conductive region.

5. The optical module according to claim 4, characterized in that, A first ground post and a second ground post are provided on the ground conductive region, the first ground post and the second ground post are located on both sides of the high-frequency signal line, and the first ground post and the second ground post are welded to the ground conductive layer.

6. The optical module according to claim 5, characterized in that, The first ground post and the second ground post are located on both sides of the fifth metal protrusion, and the distance between the first ground post and the fifth metal protrusion is equal to the distance between the second ground post and the fifth metal protrusion.

7. The optical module according to claim 3, characterized in that, A second metal protrusion is provided on the light-emitting electrode. A third metal protrusion and a fourth metal protrusion are provided on the adapter board. The third metal protrusion and the fourth metal protrusion are connected to the conductive wire. The third metal protrusion is welded to the first metal protrusion, and the fourth metal protrusion is welded to the second metal protrusion. A sixth metal protrusion is provided on the modulation electrode. A seventh metal protrusion and an eighth metal protrusion are provided on the adapter board. The seventh metal protrusion is welded to the fifth metal protrusion, and the eighth metal protrusion is welded to the sixth metal protrusion.

8. The optical module according to claim 1, characterized in that, The substrate is a ceramic substrate, and the adapter board is a ceramic adapter board.

9. An optical module, characterized in that, Comprising: A circuit board, on which drive signal lines, power supply pads and ground pads are provided; A light-emitting component, electrically connected to the circuit board, and the light-emitting component is used for generating and outputting an optical signal; wherein, the light-emitting component includes: A substrate, on which a ground conductive region, a power supply line and a high-frequency signal line are provided. The power supply line is not connected to the high-frequency signal line and the ground conductive region. The ground conductive region is wire-bonded to the ground pad. One end of the power supply line is wire-bonded to the power supply pad, and one end of the high-frequency signal line is wire-bonded to the drive signal line. A laser chip, mounted on the substrate. The laser chip includes a light-emitting region and a modulation region. On the top surface of the laser chip, a light-emitting electrode, a modulation electrode, a first ground electrode and a second ground electrode are provided. The light-emitting electrode is connected to the light-emitting region, the modulation electrode is connected to the modulation region, and the first ground electrode and the second ground electrode are located on both sides of the modulation electrode. An adapter board, mounted on the laser chip. On the side surface of the adapter board facing the substrate, a ground conductive layer, a conductive wire and a signal line are provided. The conductive wire is not connected to the signal line and the ground conductive layer. One end of the conductive wire is welded to the light-emitting electrode, and the other end of the conductive wire is welded to the other end of the power supply line to transmit a bias current to the light-emitting region. One end of the signal line is welded to the modulation electrode, and the other end of the signal line is welded to the other end of the high-frequency signal line to transmit a current signal to the modulation region. One end of the ground conductive layer is welded to the first ground electrode and the second ground electrode, and the other end of the ground conductive layer is welded to the ground conductive region.

10. The optical module according to claim 9, characterized in that, The power supply line includes a first power supply line, a second power supply line and a third power supply line. One end of the first power supply line is wire-bonded to the power supply pad. The other end of the first power supply line is connected to one end of the second power supply line. The other end of the second power supply line is connected to one end of the third power supply line. The other end of the third power supply line is welded to the conductive wire. The third power supply line is located between the laser chip and the high-frequency signal line, and the conductive wire is parallel to the signal line.

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