WO2024051129A1

WO2024051129A1 - Optical module

Info

Publication number: WO2024051129A1
Application number: PCT/CN2023/080939
Authority: WO
Inventors: 张加傲; 王欣南; 王彦波; 邵宇辰; 慕建伟
Original assignee: 青岛海信宽带多媒体技术有限公司
Priority date: 2022-09-07
Filing date: 2023-03-10
Publication date: 2024-03-14
Also published as: CN117706703A

Abstract

Provided in the present disclosure is an optical module. The optical module comprises a circuit board, a laser driving chip, a laser and a heating element, wherein the laser driving chip, the laser and the heating element are arranged on the circuit board, and the laser is electrically connected to the laser driving chip; the circuit board comprises a first heat transfer layer, a filling layer and a second heat transfer layer which are stacked, and the first heat transfer layer is located on the circuit board and forms a gap with the laser driving chip; the heating element is located on the first heat transfer layer, and the first heat transfer layer surrounds the laser and is spaced apart from the periphery of the laser by the gap, so as to transfer heat to the laser; and a plurality of heat conduction through holes are formed between the second heat transfer layer and the first heat transfer layer, the first heat transfer layer is connected to the second heat transfer layer by means of the heat conduction through holes, and the second heat transfer layer is connected to the laser by means of the heat conduction through hole in contact with the laser. According to the present disclosure, the circuit board is provided with the first and second heat transfer layers which are connected by means of the heat conduction through holes, the first heat transfer layer surrounds the laser, and heat of the heating element is transferred to the laser by means of the first and second heat transfer layers, so that more heat is transferred, and the heat transfer efficiency is higher.

Description

Optical module

This disclosure claims priority with the publication number 202211091560.3 filed with the Chinese Patent Office on September 7, 2022, the entire content of which is incorporated into this disclosure by reference.

Technical field

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

Background technique

With the development of new services and application models such as cloud computing, mobile Internet, and video, the development and progress of optical communication technology has become increasingly important. In optical communication technology, optical modules are tools for realizing mutual conversion of optical and electrical signals. They are one of the key components in optical communication equipment. With the development of optical communication technology, the transmission rate of optical modules continues to increase.

Contents of the invention

Some embodiments of the present disclosure provide an optical module. The optical module includes a circuit board, a laser driver chip, a laser, and a heating component. The circuit board includes a stacked first heat transfer layer, a filling layer, and a second heat transfer layer. A heat transfer layer is located on the upper surface of the circuit board, and a filling layer is located between the first heat transfer layer and the second heat transfer layer. The filling layer is used to connect the first heat transfer layer and the second heat transfer layer. The laser driver chip is disposed on the upper surface of the circuit board, and there is a gap between the first heat transfer layer and the laser driver chip. The first heat transfer layer surrounds the laser and is spaced apart from the periphery of the laser by a gap. The soldering pad on the top surface of the laser is electrically connected to the laser driver chip through wire bonding. The heating component is located on an upper surface of the first heat transfer layer and conducts heat to the first heat transfer layer, and the first heat transfer layer is configured to conduct heat to the laser. A plurality of thermal vias passing through the filling layer are provided between the second heat transfer layer and the first heat transfer layer. The first heat transfer layer is connected to the second heat transfer layer through the thermal vias; the second heat transfer layer is connected to the second heat transfer layer through the thermal vias. Thermal vias that the laser contacts are connected to the laser to conduct heat to the laser through the thermal vias.

Description of the drawings

In order to explain the technical solutions in the present disclosure more clearly, the drawings required to be used in some embodiments of the present disclosure will be briefly introduced below. Obviously, the drawings in the following description are only appendices of some embodiments of the present disclosure. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings. In addition, the drawings in the following description can be regarded as schematic diagrams and are not intended to limit the actual size of the product, the actual flow of the method, the actual timing of the signals, etc. involved in the embodiments of the present disclosure.

Figure 1 is a partial architecture diagram of an optical communication system according to some embodiments of the present disclosure;

Figure 2 is a partial structural diagram of a host computer provided according to some embodiments of the present disclosure;

Figure 3 is a structural diagram of an optical module provided according to some embodiments of the present disclosure;

Figure 4 is a partial exploded view of an optical module provided according to some embodiments of the present disclosure;

Figure 5 is a perspective view of a circuit board in an optical module provided according to some embodiments of the present disclosure;

Figure 6 is a perspective view of a circuit board in an optical module from another perspective according to some embodiments of the present disclosure;

Figure 7 is an enlarged schematic diagram of point A in the optical module shown in Figure 6;

Figure 8 is an exploded schematic diagram of point A in the optical module shown in Figure 6;

Figure 9 is a partial cross-sectional view of a circuit board in an optical module provided according to some embodiments of the present disclosure;

Figure 10 is a partial structural diagram of a circuit board in an optical module provided according to some embodiments of the present disclosure;

Figure 11 is a partial structural diagram of a circuit board in an optical module from another perspective according to some embodiments of the present disclosure;

Figure 12 is a schematic diagram of heat transfer on a circuit board in an optical module according to some embodiments of the present disclosure;

Figure 13 is a schematic diagram 2 of heat transfer on a circuit board in an optical module according to some embodiments of the present disclosure;

Figure 14 is a schematic diagram 3 of heat transfer on a circuit board in an optical module according to some embodiments of the present disclosure.

Detailed ways

The technical solutions in some embodiments of the present disclosure will be described clearly and in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only some of the embodiments of the present disclosure, rather than all of the embodiments. Based on the embodiments provided by this disclosure, all other embodiments obtained by those of ordinary skill in the art fall within the scope of protection of this 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. Interpreted as open and inclusive, it means "including, but not limited to." In the description of the specification, the terms "one embodiment", "some embodiments", "exemplary embodiments", "example", "specific "example" or "some examples" and the like are intended to indicate that a particular feature, structure, material or characteristic associated with the embodiment or example is included in at least one embodiment or example of the present disclosure. The schematic representations of the above terms do not necessarily refer 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 configured for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Therefore, features defined as "first" and "second" may explicitly or implicitly include one or more of these features. In the description of the embodiments of the present disclosure, unless otherwise specified, "plurality" means two or more.

In describing some embodiments, expressions "coupled" and "connected" and their derivatives may be used. For example, some embodiments may be described using the term "connected" to indicate that two or more components are in direct or indirect physical or electrical contact with each other. As another example, the term "coupled" may be used when describing some embodiments to indicate that two or more components are in direct or indirect physical or electrical contact. However, the terms "coupled" or "communicatively coupled" may also refer to two or more components that are not in direct contact with each other but still cooperate 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 includes the following combinations of A, B and C: A only, B only, C only, A and B The combination of A and C, the combination of B and C, and the combination of 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 "suitable for" or "configured to" herein means open and inclusive language that does not exclude devices that are adapted to be configured or configured to perform additional tasks or steps.

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

As used herein, "parallel," "perpendicular," and "equal" include the stated situation as well as situations that are approximate to the stated situation within an acceptable deviation range, where Such acceptable deviation ranges are as determined by one of ordinary skill in the art taking into account the measurement in question and the errors associated with the measurement of the particular quantity (ie, the limitations of the measurement system). For example, "parallel" includes absolutely parallel and approximately parallel, and the acceptable deviation range of approximately parallel may be, for example, within 5°; "perpendicular" includes absolutely vertical and approximately vertical, and the acceptable deviation range of approximately vertical may also be, for example, Deviation within 5°. "Equal" includes absolute equality and approximate equality, wherein the difference between the two that may be equal within the acceptable deviation range of approximate equality is less than or equal to 5% of either one, for example.

Optical communication technology establishes information transmission between information processing equipment. Optical communication technology loads information onto light and uses the propagation of light to realize the transmission of information. Light loaded with information is an optical signal. The propagation of optical signals in information transmission equipment can reduce the loss of optical power and achieve high-speed, long-distance, and low-cost information transmission. The information that information processing equipment can process exists in the form of electrical signals. Optical network terminals/gateways, routers, switches, mobile phones, computers, servers, tablets, and televisions are common information processing equipment. Optical fibers and optical waveguides are common information processing equipment. transmission device.

The mutual conversion of optical signals and electrical signals between information processing equipment and information transmission equipment is achieved through optical modules. For example, an optical fiber is connected to the optical signal input end and/or the optical signal output end of the optical module, and an optical network terminal is connected to the electrical signal input end and/or the electrical signal output end of the optical module; the first optical signal transmission from the optical fiber Entering the optical module, the optical module converts the first optical signal into a first electrical signal, and the optical module transmits the first electrical signal into the optical network terminal; the second electrical signal from the optical network terminal is transmitted into the optical module, and the optical module transmits the second electrical signal into the optical module. The electrical signal is converted into a second optical signal, and the optical module transmits the second optical signal into the optical fiber. Since information processing equipment can be connected to each other through electrical signal networks, at least one type of information processing equipment needs to be directly connected to the optical module. It is not required that all types of information processing equipment are directly connected to the optical module. The information of the optical module is directly connected. The processing equipment is called the host computer of the optical module.

Figure 1 is a partial architecture diagram of an optical communication system according to some embodiments of the present disclosure. As shown in Figure 1, the optical communication system is partially represented by 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.

One end of the optical fiber 101 extends toward the remote information processing device 1000, and the other end is connected to the optical interface of the optical module 200. The optical signal can undergo total reflection in the optical fiber 101. The propagation of the optical signal in the total reflection direction can almost maintain the original optical power. The optical signal undergoes total reflection multiple times in the optical fiber 101 and will come from the direction of the remote information processing device 1000. The optical signal is transmitted into the optical module 200, or the light from the optical module 200 is propagated toward the remote information processing device 1000 to realize long-distance information transmission with low power loss.

The number of optical fibers 101 may be one or multiple (two or more); the optical fibers 101 and the optical module 200 may be pluggable or fixedly connected.

The host computer 100 has an optical module interface 102, and the optical module interface 102 is configured to access the optical module 200, so that the host computer 100 and the optical module 200 establish a one-way/bi-directional electrical signal connection; the host computer 100 is configured to connect to the optical module 200. 200 provides data signals, or receives data signals from the optical module 200, or monitors the working status of the optical module 200. Monitor and control.

The host computer 100 has an external electrical interface, such as a Universal Serial Bus interface (Universal Serial Bus, USB) and a network cable interface 104. The external electrical interface can be connected to an electrical signal network. For example, the network cable interface 104 is configured to connect to the network cable 103 so that the host computer 100 and the network cable 103 establish a one-way/bi-directional electrical signal connection.

Optical network terminals (ONU, Optical Network Unit), optical line terminals (OLT, Optical Line Terminal), optical network equipment (ONT, Optical Network Terminal) and data center servers are common host computers.

One end of the network cable 103 is connected to the local information processing device 2000, and the other end is connected to the host computer 100. The network cable 103 establishes an electrical signal connection between the local information processing device 2000 and the host computer 100.

For example, the third electrical signal sent by the local information processing device 2000 is transmitted to the host computer 100 through the network cable 103. The host computer 100 generates a second electrical signal based on the third electrical signal, and the second electrical signal from the host computer 100 is transmitted into the optical module. 200. The optical module 200 converts the second electrical signal into a second optical signal. The optical module 200 transmits the second optical signal into the optical fiber 101. The second optical signal is transmitted to the remote information processing device 1000 in the optical fiber 101.

For example, the first optical signal from the direction of the remote information processing device 1000 is propagated through the optical fiber 101. The first optical signal from the optical fiber 101 is transmitted into 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 based on the first electrical signal. The host computer 100 transmits the fourth electrical signal to the local information processing device 2000.

The optical module is a tool that realizes the mutual conversion of optical signals and electrical signals. During the above-mentioned conversion process of optical signals and electrical signals, the information does not change, and the encoding and decoding method of the information can change.

Figure 2 is a partial structural diagram of a host computer provided according to some embodiments of the present disclosure. In order to clearly show the connection relationship between the optical module 200 and the host computer 100, FIG. 2 only shows the structures related to the host computer 100 and the optical module 200. As shown in Figure 2, the host computer 100 also includes a PCB circuit board 105 provided in the housing, a cage 106 provided on the surface of the PCB circuit board 105, a radiator 107 provided on the cage 106, and a heat sink 107 provided inside the cage 106. In the electrical connector (not shown in the figure), the heat sink 107 has a protruding structure that increases the heat dissipation area, and the fin-like structure is a common protruding structure.

The optical module 200 is inserted into the cage 106 of the host computer 100, and the optical module 200 is fixed by the cage 106. The heat generated by the optical module 200 is conducted to the cage 106, and then diffused through the heat sink 107. After the optical module 200 is inserted into the cage 106, the electrical interface of the optical module 200 is connected to the electrical connector inside the cage 106.

FIG. 3 is a structural diagram of an optical module provided according to some embodiments of the present disclosure, and FIG. 4 is a partial exploded view of an optical module provided according to some embodiments of the present disclosure. As shown in FIGS. 3 and 4 , the optical module 200 includes a shell, a circuit board 300 disposed in the shell, a light emitting component 400 and a light receiving component. However, the present disclosure is not limited thereto. In some embodiments, the optical module 200 includes one of a light emitting component 400 and a light receiving component.

The housing includes an upper housing 201 and a lower housing 202. The upper housing 201 is covered on the lower housing 202 to form the above-mentioned housing with two openings 204 and 205; the outer contour of the housing generally presents a square body.

In some embodiments, the lower shell 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 shell 201 includes a cover plate, and the cover plate covers the two lower sides of the lower shell 202 board to form the above-mentioned shell.

In some embodiments, the lower shell 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 shell 201 includes a cover plate, and two lower side plates located on both sides of the cover plate and perpendicular to the cover plate. Two upper side panels, The two upper side plates are combined with the two lower side plates to realize that the upper housing 201 is covered with the lower housing 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 . For example, the opening 204 is located at the end of the optical module 200 (the right end of FIG. 3 ), and the opening 205 is also located at the end of the optical module 200 (the left end of FIG. 3 ). Alternatively, the opening 204 is located at an end of the optical module 200 and the opening 205 is located at a side of the optical module 200 . The opening 204 is an electrical interface, and the golden finger 301 of the circuit board 300 extends from the electrical interface and is inserted into the electrical connector of the host computer; the opening 205 is an optical port, configured to access the optical fiber 101, so that the optical fiber 101 is connected to the optical module 200 The light emitting component 400 and/or the light receiving component in .

The assembly method of combining the upper housing 201 and the lower housing 202 is used to facilitate the installation of the circuit board 300, the light emitting component 400, the light receiving component and other components into the above-mentioned housing. The upper housing 201 and the lower housing 202 can be connected to each other. These components form an encapsulated protection. In addition, when assembling components such as the circuit board 300, the light emitting component 400, and the light receiving component, it is convenient to deploy the positioning components, heat dissipation components, and electromagnetic shielding components of these devices, which is conducive to automated production.

In some embodiments, the upper housing 201 and the lower housing 202 are made of metal materials, which facilitates electromagnetic shielding and heat dissipation.

In some embodiments, the light module 200 also includes an unlocking component 203 located outside its housing. The unlocking component 203 is configured to realize a fixed connection between the optical module 200 and the host computer 100 , or to release the fixed connection between the optical module 200 and the host computer 100 .

For example, the unlocking component 203 is located on the outside of the two lower side plates of the lower housing 202 and includes an engaging component that matches the cage 106 of the host computer. When the optical module 200 is inserted into the cage 106, the optical module 200 is fixed in the cage 106 by the engaging parts of the unlocking part 203; when the unlocking part 203 is pulled, the engaging parts of the unlocking part 203 move accordingly, thereby changing the engaging parts. The connection relationship with the host computer is to release the fixed connection between the optical module 200 and the host computer, so that the optical module 200 can be pulled out of the cage 106 .

The circuit board 300 includes circuit wiring, electronic components, chips, etc. The electronic components and chips are connected together according to the circuit design through the circuit wiring to realize functions such as power supply, electrical signal transmission, and grounding. Electronic components may include, for example, capacitors, resistors, transistors, and Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET). The chip may include, for example, a microcontroller unit (Microcontroller Unit, MCU), a laser driver chip, a transimpedance amplifier (Transimpedance Amplifier, TIA), a limiting amplifier (Limiting Amplifier, LA), and a clock data recovery chip (Clock and Data Recovery, CDR). , power management chip, 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 perform a load-bearing function. For example, the rigid circuit board can stably carry the above-mentioned electronic components and chips; the rigid circuit board can also be easily inserted into the host computer cage. in electrical connectors.

The circuit board 300 also includes a gold finger 301 formed on an end surface thereof, and the gold finger 301 is composed of a plurality of independent pins. The circuit board 300 is inserted into the cage 106, and the golden finger 301 is connected to the electrical connector in the cage 106. The golden fingers 301 may be provided only on one side of the circuit board 300 (for example, the upper surface shown in FIG. 4 ), or may be provided on the upper and lower surfaces of the circuit board 300 to provide more pins. The golden finger 301 is configured to establish an electrical connection with the host computer to realize power supply, grounding, I2C signal transmission, data signal transmission, etc.

Of course, flexible circuit boards are also used in some optical modules. Flexible circuit boards are generally used in conjunction with rigid circuit boards to supplement the rigid circuit boards.

The light emitting component 400 and/or the light receiving component are located on the side of the circuit board 300 away from the gold finger 301; in some embodiments, the light emitting component 400 and the light receiving component are physically separated from the circuit board 300, and then passed through corresponding The flexible circuit board or electrical connector is electrically connected to the circuit board 300; in some embodiments, the light emitting component and/or the light receiving component can be directly disposed on the circuit board 300, can be disposed on the surface of the circuit board, or can be disposed on the circuit board 300. side of the circuit board.

In some embodiments, the light emitting component 400 may include optical components such as lasers and lenses. The laser is electrically connected to the laser driver chip on the circuit board 300 , and the laser driver chip is electrically connected to the data processing chip 302 on the circuit board 300 . The data processing chip 302 transmits the electrical signal transmitted by the golden finger 301 to the laser driver chip. The laser driver chip provides a driving current to the laser, causing the laser to generate an optical signal. The optical signal is transmitted through the optical fiber adapter 500 to realize the emission of light.

The light receiving component may include optical components such as lenses and detectors. The external optical signal transmitted by the fiber optic adapter is transmitted to the detector through the lens. The detector converts the externally transmitted optical signal into an electrical signal. The electrical signal passes through the cross-connections on the circuit board 300. Amplified by a resistor amplifier, etc., and then transmitted to the data processing chip 302. The data processing chip 302 processes the electrical signal and then transmits it to the host computer via the golden finger 301 to realize light reception.

In some embodiments, the operating temperature of the laser in the optical module is between 15°C and 75°C. In most cases, the heat dissipation of the optical module is not concerned at low temperatures. Precisely because of this, poor laser performance that may be caused by low temperatures is ignored. The optical module can work normally in a normal temperature environment. Once it is moved to a low temperature environment (such as industrial-grade low temperature), the laser may crack in performance due to low temperature, and the optical module will not work properly due to cracking in laser performance.

For example, Vertical Cavity Surface Emitting Laser (VCSEL) is developed based on gallium arsenide semiconductor material. It has the advantages of small size, circular output spot, low threshold current, and easy integration into large-area arrays. It is widely used in Used in the field of optical communications. During the continuous use of VCSEL lasers, it was found that the performance of VCSEL lasers generally cracked seriously in low-temperature environments, seriously affecting the normal operation and use of optical modules.

In some embodiments, the laser can be placed on a semiconductor refrigerator through the COC substrate, and the semiconductor refrigerator is placed on the surface of the circuit board 300 to conduct heat conduction to the laser through the semiconductor refrigerator. The negative electrode of the laser is directly welded to the pad on the surface of the COC substrate, and the positive electrode of the laser is connected to the COC substrate through wire bonding. The COC substrate can be electrically connected to the circuit board 300 through wire bonding to achieve electrical connection between the laser and the circuit board 300 .

In some embodiments of the present disclosure, the bottom surface of the laser is placed directly on the surface of the circuit board 300 , and the laser is bonded to the surface of the circuit board 300 using glue. Since the glue has great fluidity on the metal copper, some areas of the circuit board 300 will be removed from the copper, and the laser will be bonded to the resin medium of the circuit board 300 through the glue.

A welding pad is provided on the top surface of the laser, and the welding pad is electrically connected to the laser driver chip on the circuit board 300 through wiring to receive the driving current provided by the laser driver chip, thereby driving the laser to generate a beam.

Since the laser is directly bonded to the surface of the circuit board 300 through glue, it is inconvenient to install a heating component under the laser. In order to heat the laser, a heating component can be provided on the surface of the circuit board 300. The heat generated by the heating component can pass through Circuit board 300 conducts to the laser.

In some embodiments, since the circuit board 300 is composed of multi-layer boards, and adjacent boards are bonded with resin, the circuit board 300 has poor thermal conductivity and heat dissipation performance. When the laser is directly bonded to the circuit board 300, the heat generated by the heating component is only conducted to the VCSEL laser through a medium such as resin, and the heating efficiency and heating amount are bound to be far less effective than conduction through metal copper, resulting in conduction to the VCSEL. Lasers generate less heat.

Based on the above problems, when the laser is directly bonded to the surface of the circuit board 300 in this disclosure, the circuit board 300 A heat transfer layer and a thermal via hole are added to the surface. The heat transfer layer is located on the outer periphery of the laser. The laser is in contact with a thermal via hole. In this way, the heat generated by the heating component is transmitted to the laser through the heat transfer layer and the thermal via hole, so that it is transmitted to the laser. There is more heat and the heat transfer efficiency is faster.

Figure 5 is a perspective view of a circuit board in an optical module provided according to some embodiments of the present disclosure. Figure 6 is a perspective view of a circuit board in an optical module provided according to some embodiments of the present disclosure from another perspective. Figure 7 is Figure 6 shows an enlarged schematic diagram of position A in the optical module. As shown in Figure 5, Figure 6 and Figure 7, the optical module provided by some embodiments of the present disclosure includes a laser driver chip 401, a laser 402 and a heating component. The laser driver chip 401 is disposed on the upper surface of the circuit board 300. The laser driver chip 401 is connected to the data processing chip 302 provided on the circuit board 300, so that the data processing chip 302 transmits the electrical signal to the laser driver chip 401 through the signal line.

The laser 402 is bonded to the upper surface of the circuit board 300 through glue, and the laser 402 is electrically connected to the laser driver chip 401 through wire bonding. The laser driver chip 401 provides a driving current to the laser 402 through wiring. The laser 402 generates an optical signal driven by the driving current, and the optical signal is emitted through the optical fiber adapter 500 .

In some embodiments, the laser 402 may be a VCSEL laser, the light emitting direction of the VCSEL laser is perpendicular to the circuit board 300 , and the light incident direction of the fiber optic adapter 500 is parallel to the circuit board 300 . In order to enable the emitted light perpendicular to the circuit board 300 to be coupled into the fiber optic adapter 500, the light emitting component 400 further includes a lens component that is covered above the laser 402 and is configured to change the propagation direction of the emitted light. , reflecting the emitted light perpendicular to the circuit board 300 into emitted light parallel to the circuit board 300 , so that the reflected emitted light can be coupled to the fiber optic adapter 500 .

In some embodiments, the heating component may be a heating resistor 403. The heating resistor 403 is disposed on the upper surface of the circuit board 300. The first electrode 404 and the second electrode 405 are also disposed on the upper surface of the circuit board 300. One electrode 404 and the second electrode 405 are both electrically connected to the heating circuit on the circuit board 300, and the heating resistor 403 is located on the first electrode 404 and the second electrode 405, so that the heating circuit on the circuit board 300 passes through the first electrode 404, The second electrode 405 supplies power to the heating resistor 403, so that the heating resistor 403 supplies power for heating when the optical module is in a low temperature environment.

In some embodiments, the heating component is not limited to the heating resistor 403, as long as the component can provide power for heating and conduct the generated heat to the laser 402, they all fall within the protection scope of the embodiments of the present disclosure.

In some embodiments, in order to control the heating resistor 403 to start or stop heating, an MCU and a temperature sensor can also be provided on the circuit board 300. The temperature sensor is used to collect the operating temperature of the laser in the optical module and transfer the laser operating temperature to the MCU. , the MCU compares the laser operating temperature with the preset temperature.

If the operating temperature of the laser is lower than the preset temperature, it means that the optical module is in a low-temperature environment, and the MCU controls the heating resistor 403 to provide power and heat to heat the laser 402 and increase the operating temperature of the laser.

If the laser operating temperature is not lower than the preset temperature, it means that the optical module is in a normal working environment and the heating resistor 403 does not work.

In some embodiments, a temperature sensor can also be provided in the MCU. The temperature sensor collects the operating temperature of the laser in the optical module and stores the collected operating temperature of the laser in the register of the MCU. The MCU can read the laser operating temperature in the register and control the starting and stopping of the heating resistor 403 according to the laser operating temperature.

FIG. 8 is an exploded schematic diagram of point A in the optical module shown in FIG. 6 , and FIG. 9 is a partial cross-sectional view of a circuit board in an optical module according to some embodiments of the present disclosure. As shown in Figures 8 and 9, in order to conduct the heat generated by the heating resistor 403 to the laser 402, the circuit board 300 includes a first heat transfer layer 410, a filling layer 411 and a second heat transfer layer 412. The first heat transfer layer 410 is located on the upper surface of the circuit board 300 , the second heat transfer layer 412 is located below the first heat transfer layer 410 , and the filling layer 411 is located between the first heat transfer layer 410 and the second heat transfer layer 412 , the first heat transfer layer 410 is connected to the second heat transfer layer 412 through the filling layer 411.

The first heat transfer layer 410 covers the projection area of the heating resistor 403 on the circuit board 300. The laser 402 can be disposed on the first heat transfer layer 410, and the heating resistor 403 is located above the first heat transfer layer 410. In this way, the heating resistor 403 generates The heat is conducted to the first heat transfer layer 410, and the first heat transfer layer 410 conducts the heat to the laser 402 to heat the laser 402.

In some embodiments, there is a gap between the first heat transfer layer 410 and the laser driver chip 401, which can prevent the first heat transfer layer 410 from being connected to the laser driver chip 401, thus avoiding the conduction of heat conducted by the first heat transfer layer 410. to the laser driver chip 401, preventing the temperature from affecting the laser driver chip 401.

In some embodiments, since the laser 402 is pasted on the circuit board 300 using glue, and the glue has fluidity, in order to prevent the glue from flowing onto the first heat transfer layer 410 and affecting the thermal conductivity of the first heat transfer layer 410, the A heat transfer layer 410 is provided with a mounting groove 408 that penetrates the first heat transfer layer 410 . The laser 402 is disposed on the filling layer 411 exposed at the mounting groove 408 , and there is a gap between the laser 402 and the inner wall of the mounting groove 408 . In this way, when the laser 402 is pasted, the glue may flow to the gap between the laser 402 and the mounting groove 408 , but will not flow to the first heat transfer layer 410 .

The first heat transfer layer 410 includes a first heat transfer sub-layer 406 and a second heat transfer sub-layer 407. One side of the first heat transfer sub-layer 406 is close to and has a gap with the laser driver chip 401. The first heat transfer sub-layer 406 The opposite side is connected to the second heat transfer sub-layer 407, so that the first heat transfer sub-layer 406 and the second heat transfer sub-layer 407 form the first heat transfer layer 410 on the upper surface of the circuit board 300.

The mounting groove 408 is provided on the first sub-heat transfer layer 406, and the mounting groove 408 is provided with an opening on one side facing the laser driver chip 401, and the opening is connected with the mounting groove 408. After placing the laser 402 in the installation groove 408 in this way, glue can be injected into the bottom of the laser 402 through the opening. This can reduce the amount of glue and prevent the glue from flowing to the first sub-heat transfer layer 406.

In some embodiments, the first sub-heat transfer layer 406 is arranged along the left-right direction, the second sub-heat transfer layer 407 is arranged along the front-to-back direction, and the second sub-heat transfer layer 407 and the first sub-heat transfer layer 406 are perpendicular to each other, such that The first sub-heat transfer layer 406 and the second sub-heat transfer layer 407 form a T-shaped heat transfer layer.

The second sub-heat transfer layer 407 is located in the gap between the first electrode 404 and the second electrode 405, and the heating resistor 403 is located above the second sub-heat transfer layer 407, so that the second sub-heat transfer layer 407 can maximize the Receive the heat generated by the heating resistor 403. In this way, the heating resistor 403 generates heat when the first electrode 404 and the second electrode 405 are powered on, and the heat is conducted to the second sub-heat transfer layer 407 by thermal radiation, and the second sub-heat transfer layer 407 conducts the heat to the first sub-heat transfer layer 407 . Sub heat transfer layer 406.

In some embodiments, gaps may exist between the first electrode 404 and the second electrode 405 and the first sub-heat transfer layer 406 and the second sub-heat transfer layer 407 to prevent the circuit board 300 from being transferred to the first electrode 404 and the second sub-heat transfer layer 407 . The electrical signals from the two electrodes 405 are transmitted to the first sub-heat transfer layer 406 and the second sub-heat transfer layer 407 .

Since there is a gap between the first sub-heat transfer layer 406 and the laser 402, the heat conducted by the first sub-heat transfer layer 406 is conducted to the laser 402 by thermal radiation to heat the laser 402.

In some embodiments, the length dimension of the first sub-heat transfer layer 406 in the left-right direction is greater than the length dimension of the second sub-heat transfer layer 407 in the left-right direction, so that the heat transfer area of the first sub-heat transfer layer 406 is larger than that of the second sub-heat transfer layer 407 . Heat transfer layer 407 heat transfer area, and the first heat transfer sub-layer 406 surrounds the laser 402 . In this way, the first heat transfer sub-layer 406 can radiate heat from the surroundings of the laser 402 to the laser 402, making the heat transfer efficiency faster.

In some embodiments, since the laser 402 is disposed on the filling layer 411 exposed by the mounting groove 408, in order to increase the heat conduction rate to the laser 402, a thermal via 409 is provided on the filling layer 411 exposed by the mounting groove 408, and the thermal via hole 409 is connected to the second heat transfer layer 412, and the laser 402 is disposed on the heat conduction via 409, so that the laser 402 is connected to the second heat transfer layer 412 through the heat conduction via 409. In this way, the heat conducted by the second heat transfer layer 412 can be directly conducted to the bottom of the laser 402 through the thermal via 409 to increase the heat conduction rate.

The structure of the second heat transfer layer 412 is the same as that of the first heat transfer layer 410. Therefore, the second heat transfer layer 412 includes a third sub-heat transfer layer and a fourth sub-heat transfer layer. The first sub-heat transfer layer 406 is in the third sub-heat transfer layer. The projection of the second heat transfer layer 412 coincides with the third sub-heat transfer layer, and the projection of the second sub-heat transfer layer 407 on the second heat transfer layer 412 coincides with the fourth sub-heat transfer layer, so that the third sub-heat transfer layer The thermal layer and the fourth sub-heat transfer layer form a T-shaped heat transfer layer.

A plurality of thermal vias 409 are provided between the first heat transfer layer 410 and the second heat transfer layer 412. The heat of the first heat transfer layer 410 is conducted to the second heat transfer layer 412 through the thermal vias 409. In some embodiments, a plurality of thermal conductive vias 409 are provided between the first heat transfer sub-layer 406 and the third heat transfer sub-layer, and a plurality of thermal conductive vias 409 are provided between the second heat transfer sub-layer 407 and the fourth heat transfer sub-layer. There are thermal conductive vias 409. After the heat generated by the heating resistor 403 is radiated to the second sub-heat transfer layer 407, the second sub-heat transfer layer 407 conducts part of the heat to the first sub-heat transfer layer 406. The second sub-heat transfer layer 407 The remaining heat is conducted to the fourth heat transfer sub-layer through the thermal via 409 .

The first sub-heat transfer layer 406 conducts part of the heat to the laser 402 by thermal radiation, and the first sub-heat transfer layer 406 conducts the remaining heat to the third sub-heat transfer layer through the thermal via 409 . The fourth heat transfer sub-layer conducts heat to the third heat transfer sub-layer, and the third heat transfer sub-layer conducts heat directly to the bottom of the laser 402 through the thermal via 409 .

In some embodiments, the first heat transfer layer 410 and the second heat transfer layer 412 are both heat transfer copper layers, and the heat conduction via 409 is a metal via. For example, the heat conduction via 409 is a copper via, and the filling layer 411 is The resin dielectric layer, such that the first heat transfer layer 410, the second heat transfer layer 412 and the filling layer 411 can all conduct heat to the laser 402, so that the heat transfer efficiency to the laser 402 is faster.

Figure 10 is a partial structural diagram of a circuit board in an optical module provided according to some embodiments of the present disclosure. Figure 11 is a partial structural diagram of a circuit board in an optical module provided according to some embodiments of the present disclosure from another perspective. . As shown in Figures 10 and 11, on the upper surface of the circuit board 300, the first sub-heat transfer layer 406 and the second sub-heat transfer layer 407 form a T-shaped first heat transfer layer 410. The first sub-heat transfer layer 406 A mounting groove 408 is provided on the top, and a thermally conductive via 409 is provided on the filling layer 411 exposed at the mounting groove 408 .

On the inner layer of the circuit board 300, the third sub-heat transfer layer and the fourth sub-heat transfer layer form a T-shaped second heat transfer layer 412. There are multiple heat transfer layers disposed between the first heat transfer layer 410 and the second heat transfer layer 412. The first heat transfer layer 410 conducts heat conduction with the second heat transfer layer 412 through the heat conduction via holes 409.

In some embodiments, a metal layer is also provided on the upper surface of the circuit board 300 , and optoelectronic components such as a laser driver chip 401 , a transimpedance amplifier, and an MCU are provided on the metal layer. However, the metal layer is different from the first heat transfer layer 410 There is a gap between them to prevent the heat conducted by the first heat transfer layer 410 from diffusing to the metal layer, so that the heat can be conducted on the first heat transfer layer 410 as much as possible, and to prevent the heat from heating other optoelectronic devices on the metal layer and affecting other optoelectronic devices. device performance.

Figure 12 is a schematic diagram of heat transfer on a circuit board in an optical module according to some embodiments of the present disclosure. Figure 13 is a second schematic diagram of heat transmission on a circuit board in an optical module according to some embodiments of the present disclosure. Figure 14 is a third schematic diagram of heat transmission on a circuit board in an optical module provided according to some embodiments of the present disclosure. As shown in Figures 12, 13 and 14, since the second sub-heat transfer layer 407 extends to the bottom of the heating resistor 403, the heat generated by the heating resistor 403 radiates to the second sub-heat transfer layer 407, and then the second sub-heat transfer layer 407 The layer 407 conducts heat to the first sub-heat transfer layer 406, and the first sub-heat transfer layer 406 uses thermal radiation to radiate heat to the laser 402, so that the first heat transfer layer 410 radiates heat to the laser 402.

Since the second heat transfer layer 412 and the first heat transfer layer 410 are connected through the heat conduction via 409, the heat of the second heat transfer sub-layer 407 is conducted to the fourth heat transfer sub-section of the second heat transfer layer 412 through the heat conduction via 409. layer, the heat of the first heat transfer sub-layer 406 is conducted to the third sub-heat transfer layer of the second heat transfer layer 412 through the thermal conductive via 409. The fourth heat transfer sub-layer will also conduct heat to the third heat transfer sub-layer, and the third heat transfer sub-layer directly conducts heat to the bottom of the laser 402 through the thermal via 409, so that the second heat transfer layer 412 conducts heat to laser 402.

The optical module provided by some embodiments of the present disclosure includes a circuit board, a laser driver chip, a laser, and a heating resistor. The circuit board includes a first heat transfer layer, a second heat transfer layer, and a filling layer. The filling layer is located between the first heat transfer layer and the third heat transfer layer. Between the two heat transfer layers, it is used to connect the first heat transfer layer and the second heat transfer layer. The first heat transfer layer is located on the upper surface of the circuit board, the laser driver chip is disposed on the upper surface of the circuit board, and there is a gap between the first heat transfer layer and the laser driver chip to prevent the first heat transfer layer from contacting the upper surface of the circuit board. The laser driver chip is connected, thereby avoiding heat conduction to the laser driver chip. The first heat transfer layer covers the projection area of the laser and the heating resistor on the circuit board. The laser is disposed on the first heat transfer layer. The laser is electrically connected to the laser driver chip through wiring to control the driving current provided by the laser driver chip. Generate light signals.

The first heat transfer layer is provided with a penetrating installation groove, and a heat conduction via hole is provided between the filling layer exposed in the installation groove and the second heat transfer layer. The laser is arranged on the heat conduction via hole of the filling layer, so that the laser passes through the heat conduction via hole. Connected to the second heat transfer layer. There is a gap between the laser and the inner wall of the installation groove to prevent glue for bonding the laser from flowing onto the first heat transfer layer. The heating resistor is located above the first heat transfer layer, so that the heating resistor supplies power for heating when the optical module is at a low temperature, and the heat is conducted to the laser through the first heat transfer layer to heat the laser.

The second heat transfer layer is located below the first heat transfer layer. A plurality of thermal vias are provided between the second heat transfer layer and the first heat transfer layer, and the second heat transfer layer is connected to the laser through the thermal vias, so The first heat transfer layer conducts heat to the second heat transfer layer through the heat conduction via holes, and the second heat transfer layer conducts heat to the laser through the heat conduction via holes to heat the laser.

In the present disclosure, a first heat transfer layer and a second heat transfer layer are provided on a circuit board. The laser is placed on the circuit board, and the first heat transfer layer surrounds the laser. The heating resistor is located above the first heat transfer layer, and the first heat transfer layer The laser is connected to the second heat transfer layer through the thermally conductive via hole, and the laser is connected to the second heat transfer layer through the thermally conductive via hole. In this way, when the laser of the optical module is at a low temperature, the heat generated by the heating resistor is conducted to the first heat transfer layer, and the first heat transfer layer uses thermal radiation to radiate the heat to the laser; the first heat transfer layer will also partially The heat is conducted to the second heat transfer layer through the thermal via hole, and the second heat transfer layer directly conducts the heat to the laser through the thermal via hole.

In this way, the heat from the heating resistor is transmitted to the laser through thermal radiation and thermal conduction, which increases the heat transmitted from the heating resistor to the laser, improves the heat transfer efficiency, maintains the operating temperature of the laser, and thus avoids the impact of low-temperature environments on laser performance. adverse effects.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present disclosure, but not to limit it; 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: The technical solutions described in the foregoing embodiments can still be modified, or some of the technical features can be equivalently replaced; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and spirit of the technical solutions of the embodiments of the present disclosure. scope.

Claims

An optical module includes:

circuit board;

A laser driver chip is arranged on the upper surface of the circuit board;

The laser is pasted on the circuit board, and its top surface is electrically connected to the laser driver chip through wire bonding;

a heating component electrically connected to the circuit board, the heating component being configured to heat the laser at low temperatures;

Wherein, the circuit board includes a stacked first heat transfer layer, a filling layer and a second heat transfer layer, the first heat transfer layer is located on the upper surface of the circuit board, and the filling layer is located on the first between the heat transfer layer and the second heat transfer layer, and the filling layer connects the first heat transfer layer and the second heat transfer layer; wherein,

There is a gap between the first heat transfer layer and the laser driver chip, the heating component is located on the upper surface of the first heat transfer layer and conducts heat to the first heat transfer layer, and the first heat transfer layer a thermal layer surrounds the laser and is spaced apart from a periphery of the laser by a gap; and the first heat transfer layer is configured to conduct heat toward the laser; and,

A plurality of thermal vias passing through the filling layer are provided between the second heat transfer layer and the first heat transfer layer, and the first heat transfer layer communicates with the second heat transfer layer through the thermal vias. The heat transfer layer is connected, the second heat transfer layer is connected to the laser through a thermal via hole in contact with the laser; and the second heat transfer layer is configured to conduct heat conducted through the thermal via hole to the laser.
The optical module according to claim 1, wherein the first heat transfer layer covers the projection area of the heating component on the circuit board, and the first heat transfer layer includes a first sub-heat transfer layer and a third heat transfer layer. Two sub-heat transfer layers, one side of the first sub-heat transfer layer is adjacent to the laser driver chip and is separated by a gap;

The other side of the first sub-heat transfer layer is connected to the second sub-heat transfer layer, and the heating component is located on the upper surface of the second sub-heat transfer layer.
The optical module according to claim 2, wherein the length dimension of the first sub-heat transfer layer in the left-right direction is greater than the length dimension of the second sub-heat transfer layer in the left-right direction, and the first sub-heat transfer layer The heat transfer area is greater than the heat transfer area of the second sub-heat transfer layer.
The optical module according to claim 2 or 3, wherein a first electrode and a second electrode are provided on the circuit board, and the first electrode and the second electrode are electrically connected to the circuit board, and the The heating component is located on the first electrode and the second electrode, and the heating component is powered and heated by the first electrode and the second electrode;

There is a gap between the first electrode and the second electrode, the second heat transfer sub-layer is located in the gap, and the first electrode and the second electrode conduct heat with the first sub-layer There is a gap between the heat transfer layer and the second heat transfer sub-layer.
The optical module according to claim 4, wherein the first heat transfer sub-layer is provided with a mounting groove, and the mounting groove is provided with an opening on one side facing the laser driver chip;

The laser is located on the filling layer exposed at the installation groove, and there is a gap between the laser and the inner wall of the installation groove.
The optical module according to claim 5, wherein the filling layer exposed at the mounting groove is provided with a thermally conductive via hole, and the laser is disposed on the thermally conductive via hole.
The optical module according to any one of claims 1 to 6, wherein the shapes of the first heat transfer layer and the second heat transfer layer are both T-shaped.
The optical module according to any one of claims 1 to 7, wherein the first heat transfer layer and the second heat transfer layer are both heat transfer copper layers, and the thermal vias are copper vias.
The optical module according to any one of claims 1 to 8, wherein the filling layer is a resin dielectric layer.
The optical module according to any one of claims 1 to 9, further comprising a temperature sensor, the temperature sensor is disposed on the circuit board, and the temperature sensor is configured to collect the operating temperature of the laser in the optical module.