WO2022188473A1

WO2022188473A1 - Optical module

Info

Publication number: WO2022188473A1
Application number: PCT/CN2021/134353
Authority: WO
Inventors: 张晓磊
Original assignee: 青岛海信宽带多媒体技术有限公司
Priority date: 2021-03-10
Filing date: 2021-11-30
Publication date: 2022-09-15
Also published as: CN115079351A; CN115079351B

Abstract

The present disclosure provides an optical module, comprising a circuit board and a light emitting device. A light emitting sub-module comprises a laser substrate, and the surface of the laser substrate is provided with a first high-speed signal pad. The light emitting device further comprises a laser chip, the laser chip is disposed on the laser substrate, and the laser chip is provided with a second high-speed signal pad. The light emitting device further comprises a rigid connecting plate, one end of the bottom surface of the rigid connecting plate is electrically connected to the laser substrate, and the other end is electrically connected to an electro-absorption modulation region of the laser chip. In some embodiments of the present disclosure, the bottom surface of the rigid connecting plate is provided with a third high-speed signal pad, one end of the third high-speed signal pad is electrically connected to the first high-speed signal pad, and the other end of the third high-speed signal pad is electrically connected to the second high-speed signal pad. According to the optical module provided in the present disclosure, the connection between the laser chip and the laser substrate is realized by means of the rigid connecting plate instead of metal wire bonding, thereby avoiding the parasitic effect caused by the metal wire bonding.

Description

an optical module

This disclosure claims the priority of the application number 202110260316.4 and the patent title "An Optical Module" filed with the China Patent Office on March 10, 2021, the entire contents of which are incorporated in this disclosure by reference.

technical field

The present disclosure relates to the technical field of optical communication, and in particular, to an optical module.

Background technique

Due to the higher and higher requirements for communication bandwidth in the field of optical fiber communication, the global optical communication is in a period of rapid development. In the field of high-speed data communication, in order to ensure long-distance and high-speed transmission of data, optical modules are usually used in the field to transmit and receive light of different wavelengths.

SUMMARY OF THE INVENTION

An optical module provided by the present disclosure includes: a circuit board; an optical emission sub-module, which is electrically connected to the circuit board and is used for converting an electrical signal into an optical signal; wherein the optical emission sub-module includes a laser substrate, A first high-speed signal pad is provided; a laser chip is arranged on the laser substrate, including a light-emitting area and an electro-absorption modulation area, the light-emitting area is connected to the laser substrate by a wire, and the electro-absorption modulation area is There is a second high-speed signal pad, the second high-speed signal pad is electrically connected to the anode of the laser chip; a rigid connection board is connected across the laser substrate and the surface of the laser chip, and the bottom surface has a third high-speed signal pad , one end of the third high-speed signal pad is electrically connected to the first high-speed signal pad, and the other end of the third high-speed signal pad is electrically connected to the second high-speed signal pad, surrounding the first high-speed signal pad. The three high-speed signal pads are provided with first ground pads, and the first ground pads are electrically connected to the laser substrate.

Description of drawings

In order to illustrate the technical solutions in the present disclosure more clearly, the following briefly introduces the accompanying drawings that need to be used in some embodiments of the present disclosure. Obviously, the accompanying drawings in the following description are only the appendixes of some embodiments of the present disclosure. For those of ordinary skill in the art, other drawings can also be obtained from these drawings. In addition, the accompanying drawings in the following description may be regarded as schematic diagrams, and are not intended to limit the actual size of the product involved in the embodiments of the present disclosure, the actual flow of the method, the actual timing of signals, and the like.

FIG. 1 is a connection diagram of an optical communication system according to some embodiments;

FIG. 2 is a structural diagram of an optical network terminal according to some embodiments;

3 is a structural diagram of an optical module according to some embodiments;

4 is an exploded view of an optical module according to some embodiments;

5 is a schematic diagram of an internal structure of an optical module according to some embodiments;

6 is a schematic structural diagram of a light emission sub-module according to some embodiments;

FIG. 7 is one of schematic structural diagrams of a laser assembly of a light emitting sub-module according to some embodiments;

FIG. 8 is a second schematic structural diagram of a laser assembly of a light emitting sub-module according to some embodiments;

9 is a schematic diagram of an exploded structure of a laser assembly of a light emitting sub-module according to some embodiments;

10 is a schematic cross-sectional structural diagram of a laser assembly of a light emitting sub-module according to some embodiments;

11 is a schematic structural diagram of a laser substrate in a light emitting sub-module according to some embodiments;

12 is a schematic structural diagram of a laser chip in a light emission sub-module according to some embodiments;

13 is a schematic diagram of the overall structure of a rigid connection board in an optical module according to some embodiments;

14 is a schematic structural diagram of the bottom surface of a rigid connection board in an optical module according to some embodiments;

FIG. 15 is a schematic diagram of an equivalent circuit of an optical module according to some embodiments.

Detailed ways

The technical solutions in some embodiments of the present disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, but not 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 protection scope of the present disclosure.

Unless the context otherwise requires, throughout the specification and claims, the term "comprise" and its other forms such as the third person singular "comprises" and the present participle "comprising" are used It is interpreted as the meaning of openness and inclusion, that is, "including, but not limited to". In the description of the specification, the terms "one embodiment", "some embodiments", "exemplary embodiments", "example", "specific example" example)" or "some examples" and the like are intended to indicate that a particular feature, structure, material or characteristic related to the embodiment or example is included in at least one embodiment or example of the present disclosure. The schematic representations of the above terms are not necessarily referring to the same embodiment or example. Furthermore, the particular features, structures, materials or characteristics described may be included in any suitable manner in any one or more embodiments or examples.

Hereinafter, the terms "first" and "second" are only used for descriptive purposes, and should not be construed as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus, a feature defined as "first" or "second" may expressly or implicitly include one or more of that feature. In the description of the embodiments of the present disclosure, unless otherwise specified, "plurality" means two or more.

In describing some embodiments, the expressions "coupled" and "connected" and their derivatives may be used. For example, the term "connected" may be used in describing some embodiments to indicate that two or more components are in direct physical or electrical contact with each other. As another example, the term "coupled" may be used in describing some embodiments to indicate that two or more components are in direct physical or electrical contact. However, the terms "coupled" or "communicatively coupled" may also mean that two or more components are not in direct contact with each other, yet still co-operate or interact with each other. The embodiments disclosed herein are not necessarily limited by the content herein.

"At least one of A, B, and C" has the same meaning as "at least one of A, B, or C", and both include the following combinations of A, B, and C: A only, B only, C only, A and B , A and C, B and C, and A, B, and C.

"A and/or B" includes the following three combinations: A only, B only, and a combination of A and B.

The use of "adapted to" or "configured to" herein means open and inclusive language that does not preclude devices adapted to or configured to perform additional tasks or steps.

As used herein, "about", "approximately" or "approximately" includes the stated value as well as the average value within an acceptable range of deviation from the specified value, as described by one of ordinary skill in the art Determined taking into account the measurement in question and the errors associated with the measurement of a particular quantity (ie, limitations of the measurement system).

In optical communication technology, light is used to carry the information to be transmitted, and the optical signal carrying the information is transmitted to information processing equipment such as computers through information transmission equipment such as optical fibers or optical waveguides to complete the transmission of information. Since optical signals have passive transmission characteristics when transmitted through optical fibers or optical waveguides, low-cost and low-loss information transmission can be achieved. In addition, the signals transmitted by information transmission equipment such as optical fibers or optical waveguides are optical signals, while the signals that can be recognized and processed by information processing equipment such as computers are electrical signals. To establish an information connection between them, it is necessary to realize the mutual conversion of electrical signals and optical signals.

The optical module realizes the mutual conversion function of the above-mentioned optical signal and electrical signal in the technical field of optical fiber communication. The optical module includes an optical port and an electrical port. The optical module realizes optical communication with information transmission equipment such as optical fibers or optical waveguides through the optical port, and realizes electrical connection with an optical network terminal (for example, an optical cat) through the electrical port. It is mainly used to realize power supply, I2C signal transmission, data signal transmission and grounding; optical network terminals transmit electrical signals to information processing equipment such as computers through network cables or wireless fidelity technology (Wi-Fi).

FIG. 1 is a connection diagram of an optical communication system according to some embodiments. As shown in FIG. 1 , the optical communication system mainly includes a remote server 1000, a local information processing device 2000, an optical network terminal 100, an optical module 200, an optical fiber 101 and a network cable 103;

One end of the optical fiber 101 is connected to the remote server 1000 , and the other end is connected to the optical network terminal 100 through the optical module 200 . The optical fiber itself can support long-distance signal transmission, such as signal transmission of several kilometers (6 kilometers to 8 kilometers). On this basis, if repeaters are used, ultra-long distance transmission can theoretically be achieved. Therefore, in a common optical communication system, the distance between the remote server 1000 and the optical network terminal 100 can usually reach several kilometers, tens of kilometers or hundreds of kilometers.

One end of the network cable 103 is connected to the local information processing device 2000 , and the other end is connected to the optical network terminal 100 . The local information processing device 2000 may be any one or more of the following devices: a router, a switch, a computer, a mobile phone, a tablet computer, a television, and the like.

The physical distance between the remote server 1000 and the optical network terminal 100 is greater than the physical distance between the local information processing device 2000 and the optical network terminal 100 . The connection between the local information processing device 2000 and the remote server 1000 is completed by the optical fiber 101 and the network cable 103 ; and the connection between the optical fiber 101 and the network cable 103 is completed by the optical module 200 and the optical network terminal 100 .

The optical module 200 includes an optical port and an electrical port. The optical port is configured to be connected to the optical fiber 101, so that the optical module 200 and the optical fiber 101 can establish a two-way optical signal connection; electrical signal connection. The optical module 200 realizes the mutual conversion of optical signals and electrical signals, so as to establish a connection between the optical fiber 101 and the optical network terminal 100 . For example, the optical signal from the optical fiber 101 is converted into an electrical signal by the optical module 200 and then input into the optical network terminal 100 , and the electrical signal from the optical network terminal 100 is converted into an optical signal by the optical module 200 and input into the optical fiber 101 .

The optical network terminal 100 includes a substantially rectangular housing, and an optical module interface 102 and a network cable interface 104 disposed on the housing. The optical module interface 102 is configured to access the optical module 200, so that the optical network terminal 100 and the optical module 200 can establish a bidirectional electrical signal connection; the network cable interface 104 is configured to access the network cable 103, so that the optical network terminal 100 and the network cable 103 are connected. Establish a two-way electrical signal connection. A connection is established between the optical module 200 and the network cable 103 through the optical network terminal 100 . For example, the optical network terminal 100 transmits the electrical signal from the optical module 200 to the network cable 103, and transmits the signal from the network cable 103 to the optical module 200. Therefore, the optical network terminal 100, as the host computer of the optical module 200, can monitor the optical module 200. work. In addition to the optical network terminal 100, the host computer of the optical module 200 may also include an optical line terminal (Optical Line Terminal, OLT) and the like.

A bidirectional signal transmission channel is established between the remote server 1000 and the local information processing device 2000 through the optical fiber 101 , the optical module 200 , the optical network terminal 100 and the network cable 103 .

FIG. 2 is a structural diagram of an optical network terminal according to some embodiments. In order to clearly show the connection relationship between the optical module 200 and the optical network terminal 100 , FIG. 2 only shows the optical network terminal 100 related to the optical module 200 . structure. As shown in FIG. 2 , the optical network terminal 100 further includes a PCB circuit board 105 disposed in the housing, a cage 106 disposed on the surface of the PCB circuit board 105 , and an electrical connector disposed inside the cage 106 . The electrical connector is configured to be connected to the electrical port of the optical module 200 ; the heat sink 107 has protrusions such as fins that increase the heat dissipation area.

The optical module 200 is inserted into the cage 106 of the optical network terminal 100 , and the optical module 200 is fixed by the cage 106 . 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 that the optical module 200 and the optical network terminal 100 establish a bidirectional electrical signal connection. In addition, the optical port of the optical module 200 is connected to the optical fiber 101 , so that the optical module 200 and the optical fiber 101 establish a bidirectional electrical signal connection.

FIG. 3 is a structural diagram of an optical module according to some embodiments, and FIG. 4 is an exploded view of an optical module according to some embodiments. As shown in FIG. 3 and FIG. 4 , the optical module 200 includes an upper casing 201 , a lower casing 202 , an unlocking part 203 , a circuit board 300 and an optical transceiver assembly 400 ;

The casing includes an upper casing 201 and a lower casing 202. The upper casing 201 is covered on the lower casing 202 to form the above casing with two

openings

204 and 205; the outer contour of the casing generally presents a square body.

In some embodiments of the present disclosure, the lower casing 202 includes a bottom plate and two lower side plates located on both sides of the bottom plate and perpendicular to the bottom plate; the upper casing 201 includes a cover plate, and two sides of the cover plate are perpendicular to the cover plate. The two upper side plates are combined with the two side plates by the two side walls to realize that the upper casing 201 is covered on the lower casing 202 .

The direction of the connection between the two

openings

204 and 205 may be consistent with the length direction of the optical module 200 , or may be inconsistent with the length direction of the optical module 200 . Illustratively, the opening 204 is located at the end of the optical module 200 (the right end in FIG. 3 ), and the opening 205 is also located at the end of the optical module 200 (the left end in FIG. 3 ). Alternatively, the opening 204 is located at the end of the optical module 200 , and the opening 205 is located at the side of the optical module 200 . The opening 204 is an electrical port, and the golden fingers of the circuit board 300 protrude from the electrical port 204 and are inserted into the host computer (such as the optical network terminal 100 ); The optical fiber 101 is connected to the optical transceiver components inside the optical module 200 .

The combination of the upper casing 201 and the lower casing 202 is used to facilitate the installation of the circuit board 300, optical transceiver components and other devices into the casing. The upper casing 201 and the lower casing 202 can form encapsulation protection for these devices. In addition, when assembling components such as the circuit board 300, it is convenient to deploy the positioning components, heat dissipation components and electromagnetic shielding components of these components, which is conducive to the implementation of automated production.

In some embodiments, the upper casing 201 and the lower casing 202 are generally made of metal material, which is beneficial to realize electromagnetic shielding and heat dissipation.

In some embodiments, the optical module 200 further includes an unlocking component 203 located on the outer wall of the housing thereof, and the unlocking component 203 is configured to realize a fixed connection between the optical module 200 and the upper computer, or release the connection between the optical module 200 and the upper computer fixed connection.

For example, the unlocking components 203 are located on the outer walls of the two lower side panels of the lower casing 202, and include engaging components matching with the cage of the upper computer (eg, the cage 106 of the optical network terminal 100). When the optical module 200 is inserted into the cage of the upper computer, the optical module 200 is fixed in the cage of the upper computer by the engaging part of the unlocking part 203; when the unlocking part 203 is pulled, the engaging part of the unlocking part 203 moves accordingly, thereby changing the The connection relationship between the engaging member and the host computer is used to release the engaging relationship between the optical module 200 and the host computer, so that the optical module 200 can be pulled out from the cage of the host computer.

The circuit board 300 includes circuit traces, electronic components and chips, and the electronic components and chips are connected together according to the circuit design through the circuit traces to realize functions such as power supply, electrical signal transmission, and grounding. The electronic components may include, for example, capacitors, resistors, triodes, and metal-oxide-semiconductor field-effect transistors (Metal-Oxide-Semiconductor Field-Effect Transistor, MOSFET). The chip may include, for example, a Microcontroller Unit (MCU), a limiting amplifier (limiting amplifier), a clock and data recovery chip (Clock and Data Recovery, CDR), a power management chip, and a digital signal processing (Digital Signal Processing, DSP) chip .

The circuit board 300 is generally a rigid circuit board. Due to its relatively hard material, the rigid circuit board can also realize the bearing function. For example, the rigid circuit board can carry chips smoothly; the rigid circuit board can also be inserted into the electrical connector in the upper computer cage. .

The circuit board 300 further includes a gold finger formed on the end surface thereof, and the gold finger is composed of a plurality of pins which are independent of each other. The circuit board 300 is inserted into the cage 106 , and is electrically connected to the electrical connector in the cage 106 by gold fingers. The golden fingers can be arranged only on one side surface of the circuit board 300 (eg, the upper surface shown in FIG. 4 ), or can be arranged on the upper and lower surfaces of the circuit board 300 , so as to meet the needs of a large number of pins. The golden finger is configured to establish an electrical connection with the upper computer to realize power supply, grounding, I2C signal transmission, data signal transmission, and the like. Of course, flexible circuit boards are also used in some optical modules. Flexible circuit boards are generally used in conjunction with rigid circuit boards as a supplement to rigid circuit boards.

The optical transceiver assembly 400 includes two parts, an optical transmitting sub-module and an optical receiving sub-module, which are respectively used for transmitting and receiving optical signals. The emission sub-module generally includes a light emitter, a lens and a light detector, and the lens and the light detector are located on different sides of the light emitter. The front and back sides of the light emitter emit light beams respectively. The lens is used to converge the front of the light emitter. The emitted light beam makes the light beam emitted by the light transmitter a convergent light so as to be easily coupled to an external optical fiber; the light detector is used to receive the light beam emitted from the reverse side of the light transmitter to detect the optical power of the light transmitter. In some embodiments of the present disclosure, the light emitted by the optical transmitter enters the optical fiber after being condensed by the lens, and the light detector detects the luminous power of the optical transmitter to ensure the constancy of the emitted optical power of the optical transmitter. The optical transceiver assembly 400 will be described in detail below.

FIG. 5 is a schematic diagram of the internal structure of an optical module according to some embodiments; as shown in FIG. 5 , the optical transceiver assembly 400 in the foregoing embodiments includes an optical transmitting sub-module 500 and an optical receiving sub-module 700 , and the optical module further includes a round square The tube body 600 and the optical fiber adapter 800. In the embodiment of the present disclosure, the optical fiber adapter 800 of the optical transceiver sub-module is connected to the optical fiber, that is, the optical fiber adapter 800 is inlaid on the circular square tube body 600 for connecting the optical fiber. In some embodiments of the present disclosure, the round tube body 600 is provided with a third nozzle 603 into which the optical fiber adapter 800 is inserted. The secondary module 700 establishes an optical connection with the optical fiber adapter 800 respectively, and the light emitted and received in the optical transceiver assembly is transmitted through the same optical fiber in the optical fiber adapter, that is, the same optical fiber in the optical fiber adapter is the optical transceiver assembly. Transmission channel, optical transceiver components realize single-fiber bidirectional optical transmission mode.

The round tube body 600 is used to carry the light emitting sub-module 500 and the light receiving sub-module 700. In the embodiment of the present disclosure, the round tube body 600 is made of metal material, which is beneficial to realize electromagnetic shielding and fan heat. The round tube body 600 is provided with a first nozzle 601 and a second nozzle 602 , and the first nozzle 601 and the second nozzle 602 are respectively disposed on the adjacent side walls of the round tube body 600 . In some embodiments of the present disclosure, the first orifice 601 is provided on the side wall of the circular square tube body 600 in the length direction, and the second orifice 602 is provided on the side wall of the circular square tube body 600 in the width direction.

The light-emitting sub-module 500 is embedded in the first nozzle 601, and through the first nozzle 601, the light-emitting sub-module 500 thermally contacts the round tube body 600; the light-receiving sub-module 700 is embedded in the second nozzle 602, and passes through the second pipe The port 602 , the light receiving sub-module 700 thermally contacts the round tube body 600 . In some embodiments of the present disclosure, the light emitting sub-module 500 and the light receiving sub-module 700 are directly press-fitted into the round tube body 600, and the round tube body 600 is directly or Contact via a thermally conductive medium. The round and square tube body can be used for the heat dissipation of the light emitting sub-module 500 and the light receiving sub-module 700 , so as to ensure the heat dissipation effect of the light emitting sub-module 500 and the light receiving sub-module 700 .

The optical transmitting sub-module 500 and the optical receiving sub-module 700 are respectively used to implement optical signal transmission and optical signal reception. The light emitting sub-module 500 generally includes a light emitter, a lens and a light detector, and the lens and the light detector are located on different sides of the light emitter, respectively, the front and back sides of the light emitter emit light beams, and the lens is used for converging light emission. The light beam emitted from the front side of the light transmitter is used to make the light beam emitted by the light transmitter be convergent light to facilitate coupling to the external optical fiber; the light detector is used to receive the light beam emitted from the back side of the light transmitter to detect the optical power of the light transmitter. In some embodiments of the present disclosure, the light emitted by the optical transmitter enters the optical fiber after being condensed by the lens, and the light detector detects the luminous power of the optical transmitter to ensure the constancy of the emitted optical power of the optical transmitter.

FIG. 6 is a schematic structural diagram of a light emitting sub-module according to some embodiments; as shown in FIG. 6 , the light emitting sub-module 500 includes a tube base 501 through which the light emitting sub-module 500 and the round tube body 600 are connected. For connection, in some embodiments of the present disclosure, the tube base 501 is embedded in the first nozzle 601 of the square tube body 600 . The optical emission sub-module 500 adopts coaxial TO package, and optical modules of other packaging forms are also within the protection scope of the present disclosure; the optical transmitter is a laser assembly, and the laser assembly includes a laser chip 504 and a laser substrate 505, and the laser substrate 505 is used for carrying The laser chip 504 and the laser substrate 505 not only have a bearing function, but also have a metal layer on the surface to realize the electrical connection of the laser chip 504; the light emission sub-module 500 also includes a TEC502 and a metal heat sink 503. , the metal heat sink 503 is located on the surface of the TEC 502 , the metal heat sink 503 has a plurality of bearing surfaces, and the laser component is arranged on one of the bearing surfaces.

The laser assembly includes a laser chip 504 and a laser substrate 505 , the laser chip 504 is welded on the laser substrate 505 by gold-tin solder, and the laser substrate 505 is pasted on a bearing surface of the metal heat sink 503 . There are currently two types of lasers for optical modules, one is DML (Directly Modulated Laser), the other is EML (Electlro-absorption Modulated Laser, Electro-absorption Modulated Laser), EML is the electro-absorption modulator EAM and The integrated device of DFB laser is better than DML and consumes more power. Compared with DML, EML adds refrigerators, metal heat sinks, thermistors, etc. The specific working process of the laser chip 504 is as follows: when the optical module mode performs signal transmission, the golden finger introduces the electrical signal into the laser driver chip, the laser driver chip transmits the electrical signal to the laser, and then uses the laser to convert the electrical signal into light. Signal.

The TEC 502 is arranged on the surface of the tube base 501. In the embodiment of the present disclosure, the surface of the metal heat sink 503 also has a thermistor, which is not shown in the figure. The thermistor is arranged on the metal heat sink 503 to obtain the temperature of the metal heat sink 503. Then, the monitoring of the working temperature of the laser chip 504 is realized. The TEC 502 is fixed on the top surface of the tube base 501 , and the TEC 502 supports the heat sink metal heat sink 503 , that is, the metal heat sink 503 is fixed on the tube base 501 through the TEC 502 . In the embodiment of the present disclosure, a heat exchange surface of the TEC502 is directly attached to the socket 501, and the other heat exchange surface of the TEC502 is used for directly attaching the metal heat sink 503, which ensures that the laser chip 504 and the TEC502 can be efficiently connected. of heat transfer. When the temperature of the laser chip 504 changes, the thermistor can feed back the temperature change to the TEC driver, and the TEC 502 can be controlled by the TEC driver for cooling or heating, so that the temperature of the laser chip 504 is kept constant, so as to realize the control of the laser chip 504. Precise temperature control at the micro level. In the embodiment of the present disclosure, the surface of the socket 501 has a TEC positive pin 506a and a TEC negative pin 506b, and the positive and negative electrodes of the TEC 502 are wired to the TEC positive pin 506a and the TEC negative pin 506b respectively.

The metal heat sink 503 is arranged on the top surface of the TEC502. The metal heat sink 503 can be a tungsten-copper heat dissipation block but is not limited to a tungsten-copper fan heat block. The heat dissipation block has more heat dissipation surfaces and larger surface area for heat dissipation, which is more conducive to heat dissipation. In addition, the thickness of the L shape should be moderate, and it should be compatible with the light path and smooth. In addition, the heat dissipation block should not be too large. Too large heat dissipation block will increase the thermal capacity of TO. large, resulting in higher energy consumption and poor reliability of the required TEC cooling efficiency. It should be noted that the shape of the metal heat sink according to some embodiments is not limited to the above-mentioned shapes, as long as it can satisfy the heat dissipation function and can carry devices such as lasers, and realize the ground connection with the metal support column 508 , all belong to the embodiments of the present disclosure. protected range.

The existing scheme for electrical connection of laser chips is as follows: the negative electrode of the laser chip is fixed on the corresponding laser substrate, the laser chip is provided with its own high-speed signal pad, and the high-speed signal pad of the laser chip is connected to the laser substrate through a metal wire. However, metal wire bonding will introduce parasitic effects, so it is not an optimal solution to realize the electrical connection of the laser chip through metal wire bonding. In some embodiments of the present disclosure, the light emission sub-modules in the embodiments of the present disclosure include:

The laser substrate 505 is provided with a first high-speed signal pad;

The laser chip 504 is arranged on the laser substrate, and includes a light-emitting area and an electro-absorption modulation area, the electro-absorption modulation area has a second high-speed signal pad, and the anode of the laser chip is electrically connected to the second high-speed signal pad. connection, and the light-emitting area is connected with the laser substrate through wire bonding;

The rigid connection board 507 is formed of hard material, the bottom surface is on the same plane as the top surface of the laser substrate and the top surface of the laser chip, and the bottom surface has a third high-speed signal pad, one end of the third high-speed signal pad is electrically connected to the first high-speed signal pad, the other end of the third high-speed signal pad is electrically connected to the second high-speed signal pad, and a first ground bond is provided along the third high-speed signal pad The first ground pad is electrically connected to the laser substrate.

7 is one of the schematic structural diagrams of a laser assembly of an optical emission sub-module according to some embodiments; FIG. 8 is the second structural schematic diagram of a laser assembly of an optical emission sub-module according to some embodiments; A schematic diagram of an exploded structure of a laser assembly of an optical emission sub-module according to some embodiments; FIG. 10 is a schematic cross-sectional structure diagram of a laser assembly of an optical emission sub-module according to some embodiments; the following is a detailed description with reference to FIGS. 7-10 .

As shown in FIG. 7, one end of the rigid connection board 507 is located on the surface of the laser chip 504, and the other end is located on the surface of the laser substrate 505. The rigid connection board 507 serves as a bridge connecting the laser chip 504 and the laser substrate 505. Pads are set on the ground of the hard connection board 507 to realize the connection between the laser chip 504 and the laser substrate 505 , thereby replacing the metal wire bonding method. In some embodiments, the two ends of the rigid connection board 507 and the laser substrate 505 may be arranged at an inclination, but the inclined arrangement will cause the stress imbalance of the rigid connection board 507 to cause the rigid connection board 507 to be less stable; in some embodiments , the two ends of the rigid connection board 507 are balanced with the laser substrate 505 to increase the stability of the rigid connection board 507 and reduce the difficulty of the welding process.

In order to shorten the distance from the rigid connection board 507 to the laser substrate 505 to reduce the link loss, in the embodiment of the present disclosure, the surface of the laser substrate 505 is hollowed out to form a groove 508, and the laser chip 504 is placed in the groove 508. The ground of the connection board 507 is parallel to and in contact with the top surface of the laser substrate 505. In the embodiment of the present disclosure, the height of the groove 508 is exactly equal to the thickness of the laser chip 504; it should be noted that in the embodiment of the present disclosure, the surface of the laser substrate 505 is It is also not necessary to carry out hollowing processing, the laser chip 504 is arranged on the surface of the laser substrate 505, and the rigid connection plate 507 is arranged on the surface of the laser chip 504; and the height of the groove 508 is not uniquely limited, as long as it can accommodate the laser chip. 504 all belong to the protection scope of the embodiments of the present disclosure.

In some embodiments of the present disclosure, the length of the groove 508 can be used as a reserved space, that is, the length of the groove 508 is greater than the length of the laser chip 504 to form a reserved space, and the reserved space is used to place the backlight A detector, a backlight detector, can be used to monitor the luminous power of the laser chip 504 .

The laser substrate 505 , the laser chip 504 and the hard connection board 507 will be specifically described below with reference to FIGS. 11 to 14 .

FIG. 11 is a schematic structural diagram of a laser substrate in a light emitting sub-module according to some embodiments. As can be seen from FIG. 11 , the surface of the laser substrate 505 has grooves 508 and the surface of the laser substrate has first high-speed signal pads 5052 , A second ground pad 5051 and a third ground pad 5053 are provided at both ends of the first high-speed signal pad 5052 .

FIG. 12 is a schematic structural diagram of a laser chip in a light emitting sub-module according to some embodiments. As can be seen from FIG. 12 , the surface of the laser chip 504 has a second high-speed signal pad 5041 .

FIG. 13 is a schematic diagram of the overall structure of a rigid connection board in an optical module according to some embodiments, and FIG. 14 is a schematic diagram of the structure of the bottom surface of the rigid connection board in an optical module according to some embodiments, wherein the bottom surface refers to the connection with the laser substrate The side that is in contact with the laser chip; as shown in Figure 14, the bottom surface of the rigid connection board 507 is provided with a third high-speed signal pad 5072, and both ends of the third high-speed signal pad are provided with a ground pad 5071 and another ground weld The first ground pad formed by the connection of the disk 5073; the third high-speed signal pad 5072 and the first ground pad form a G-S-G pad to ensure that the high-frequency signal transmission mode is the GSG (ground-signal-ground) mode, and the high-frequency signal The transmission mode is GSG (ground-signal-ground) mode, that is, ground wires should be laid on both sides of the high-frequency signal line to shorten the isolation between the signal return path and the signal channel.

Both ends of the third high-speed signal pad 5072 have a first pad 5077 and a second pad 5078 respectively, and both ends of the first ground pad have a third pad 5075 and a fourth pad 5076 respectively;

The first solder joint 5077 is electrically connected to the electro-absorption modulation region of the laser chip through the first gold nugget, the second solder joint 5078 is electrically connected to the first high-speed signal pad 5052 through the second gold nugget, and the third solder joint 5075 is electrically connected to the first high-speed signal pad 5052 through the second gold nugget. The gold nugget is electrically connected to the grounding region of the laser substrate, and the fourth solder joint 5076 is electrically connected to the grounding region of the laser substrate through the fourth gold nugget.

The negative electrode of the laser chip 504, that is, the cathode is fixed on the surface of the laser substrate. When the surface of the laser substrate has a groove 508, the two sides and the ground of the groove 508 are laid with metal layers to make the groove 508 and the laser substrate 505 electrically connected That is, the groove 508 and the laser substrate 505 are electrically connected, and the negative electrode of the laser chip 504 is fixed on the surface of the groove 508, that is, the negative electrode of the laser chip 504 is indirectly fixed on the surface of the laser substrate 505. A ground metal layer is laid on the surface, and the ground metal layer is electrically connected to the ground pins on the surface of the socket 501 to realize the grounding of the negative electrode of the laser chip 504 .

Except for the second ground pad 5051 and the third ground pad 5053 , the surface of the laser substrate 505 is grounded, and a ground metal layer is laid. One end of the first ground pad is electrically connected to the second ground pad 5051 ; the other end of the first ground pad is electrically connected to the third ground pad 5053 .

The anode of the laser chip 504 is electrically connected to the second high-speed signal pad 5041 on the laser chip. The second high-speed signal pad 5041 is connected to one end of the third high-speed signal pad 5072 on the The other end of the high-speed signal pad 5072 is welded and connected to the first high-speed signal pad 5052 on the surface of the laser substrate, so that the anode of the laser chip 504 is electrically connected to the laser substrate 505 through the rigid connection board 507, and the laser substrate 505 is connected to the circuit board with It is electrically connected to the driver pad of the welding laser driving chip (Driver), so that the laser starting chip drives the laser chip to emit light signals.

The soldering process in the embodiment of the present disclosure adopts the eutectic soldering process, so gold nuggets are arranged on both ends of the third high-speed signal pad 5072 and the first ground pad disposed around the third high-speed signal pad 5072 to be based on eutectic Welding principle realizes welding.

Since the high-speed signal line on the high-speed signal pad has a certain resistance, if the impedance of the high-speed signal line and the laser chip 504 do not match, the signal output by the high-speed signal line will be seriously deteriorated. A matching resistor is provided on it, and the resistance value of the matching resistor is equal to the resistance value of the high-speed signal line, so as to realize the impedance matching between the laser chip 504 and the high-speed signal line; wire connection, the metal wire bonding at this time will further enter the parasitic effect.

In order to solve the above-mentioned solution, in the present disclosure, the matching resistor is arranged in the rigid connection board 507, and in some embodiments of the present disclosure, the third high-speed signal pad and the second ground pad and the third high-speed signal pad and the third A matching resistor 5074 is arranged between the connection lines of the ground pads. Since the rigid connection board 507 and the laser chip 504 are electrically connected, the matching resistor 5074 can be set in the rigid connection board 507 to realize the matching resistor 5074 and the laser chip 504 The connection between the laser chip and the matching resistor 5074 is avoided by metal bonding wires. In some embodiments of the present disclosure, one end of the matching resistor 5074 is connected to the first ground pad to realize grounding, and the other end of the matching resistor 5074 is connected to the third high-speed signal pad to realize the connection with the laser substrate. connect.

It can be seen from the above solution that the present disclosure avoids the method of connecting the laser chip and the laser substrate, connecting the laser chip and the matching resistor through metal wire bonding in the related technical scheme, thereby avoiding the parasitic effect introduced by the metal wire bonding. A schematic diagram of an equivalent circuit of an optical module of the embodiment, as shown in FIG. 15 , in the present disclosure, there is no inductive reactance between the laser chip and the laser substrate, the laser chip and the matching resistor, indicating that the hard connection board is used to replace the metal wire connection. way is feasible.

It can be seen from the above technical solutions that the optical module provided by the present disclosure includes a circuit board and a light emission sub-module, wherein the light emission sub-module includes a laser substrate, and the surface of the laser substrate is provided with a first high-speed signal pad formed by a high-speed signal line; The module further includes a laser chip, the laser chip is arranged on the laser substrate, the laser chip has a second high-speed signal pad, and the anode of the laser chip is electrically connected to the second high-speed signal pad; the light emission sub-module further includes a rigid connection board, One end of the bottom surface of the rigid connection board is electrically connected with the laser substrate, and the other end is electrically connected with the laser chip. In some embodiments of the present disclosure, the bottom surface of the rigid connection board is provided with a third high-speed signal pad, One end of the third high-speed signal pad is electrically connected to the first high-speed signal pad, and the other end of the third high-speed signal pad is electrically connected to the second high-speed signal pad.

That is, the anode of the laser chip is linked to the second high-speed signal pad, the second high-speed signal pad is electrically connected to one end of the third high-speed signal pad of the hard connection board, and the other end of the third high-speed signal pad of the hard connection board is electrically connected. One end is electrically connected to the first high-speed signal pad of the laser substrate, so that the anode of the laser chip is electrically connected to the laser substrate through a rigid connection board, and the laser substrate is electrically connected to the driver pad for welding the laser driver chip (Driver) on the circuit board. Therefore, the optical module provided in the present disclosure utilizes a rigid connection board to realize the link between the laser chip and the laser substrate instead of the metal wire to connect the laser chip and the laser substrate, thereby avoiding metal hitting Parasitic effects introduced by the line.

The above are only specific embodiments of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any person skilled in the art who is familiar with the technical scope disclosed in the present disclosure, think of changes or replacements, should cover within the scope of protection of the present disclosure. Therefore, the protection scope of the present disclosure should be based on the protection scope of the claims.

Claims

An optical module, characterized in that it includes:

circuit board;

an optical emission sub-module, electrically connected to the circuit board, for converting electrical signals into optical signals;

Wherein, the light emission sub-module includes:

The laser substrate is provided with a first high-speed signal pad;

The laser chip is arranged on the laser substrate, and includes a light-emitting area and an electro-absorption modulation area, the light-emitting area is connected to the laser substrate by a wire, and the electro-absorption modulation area has a second high-speed signal pad, and the second high-speed signal pad is electrically connected to the anode of the laser chip;

The rigid connection board is connected across the surface of the laser substrate and the laser chip, and the bottom surface has a third high-speed signal pad, one end of the third high-speed signal pad is electrically connected to the first high-speed signal pad, so The other end of the third high-speed signal pad is electrically connected to the second high-speed signal pad, a first ground pad is arranged around the third high-speed signal pad, and the first ground pad is connected to the laser The substrate is electrically connected.
The optical module according to claim 1, wherein the surface of the laser substrate has a groove, and the laser chip is arranged in the groove;

One end of the rigid connection board is located on the surface of the laser chip, and the other end is located on the surface of the laser substrate.
The optical module according to claim 1, wherein both ends of the third high-speed signal pad have a first pad and a second pad respectively, and both ends of the first ground pad respectively have a first pad and a second pad. Three solder joints and a fourth solder joint;

The first solder joint is electrically connected to the electro-absorption modulation region through a first gold nugget, the second solder joint is electrically connected to the first high-speed signal pad through a second gold nugget, and the third solder joint The third gold nugget is electrically connected to the ground region of the laser substrate, and the fourth solder joint is electrically connected to the ground region of the laser substrate through the fourth gold nugget.
The optical module according to claim 1, wherein a matching resistance is provided between the third high-speed signal pad and the first ground pad for matching the laser chip and the first high-speed signal impedance between pads;

One end of the matching resistor is connected to the first ground pad to realize grounding, and the other end of the matching resistor is connected to the third high-speed signal pad to realize the connection with the laser substrate.
The optical module according to claim 1, wherein the light emitting sub-module further comprises a tube seat, the surface of the tube seat has a TEC, the surface of the TEC has a metal heat sink, and the surface of the metal heat sink has a laser assembly, the laser assembly includes a laser substrate and a laser chip.
The optical module according to claim 3, wherein the two ends of the first high-speed signal pad on the surface of the laser substrate are provided with a second ground pad and a third ground pad;

One end of the first ground pad is electrically connected to the second ground pad;

The other end of the first ground pad is electrically connected to the third ground pad.
The optical module according to claim 2, wherein the height of the groove is equal to the thickness of the laser chip.
The optical module according to claim 2, wherein the bottom surface and the side surface of the groove are covered with a metal layer, so that the groove is electrically connected to the laser substrate.
The optical module according to claim 8, wherein a ground metal layer is laid on the ground of the groove, and the cathode of the laser chip is fixed on the ground metal layer.
The optical module according to claim 2, wherein the length of the groove is not less than the length of the laser chip.