An optical module package structure

Abstract

The application discloses an optical module packaging structure, which comprises a shell, a circuit board, a first device and a sub-board packaged in the shell; wherein the shell comprises a first shell and a second shell, and the outer surface of the first shell is a main heat dissipation surface; the first device is electrically connected to the circuit board through the sub-board; the surface of the circuit board is provided with a first signal line, and the surface of the sub-board is provided with an extension section; the sub-board is partially overlapped and connected to the circuit board, the first signal line on the circuit board is extended to the extension section on the sub-board; the surface of the partially overlapped sub-board and the surface of the circuit board face in opposite directions, the first device is electrically connected to the extension section on the sub-board; and the first device has a heat dissipation surface which faces and is in heat conduction connection with the first shell. By increasing the interconnection of the sub-board and the circuit board, on one hand, most of the devices can be heat dissipated through the main heat dissipation surface, and the heat dissipation performance of the module is effectively improved; on the other hand, the wiring space of the circuit board is improved, the via hole wiring is reduced, and the high-frequency performance of the module is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of optical communication technology, in particular to an optical module packaging structure. BACKGROUND

[0002] As shown in Figure 1 and 2 , the optical module generally comprises a shell 10' and an optoelectronic assembly packaged in the shell 10'. The optoelectronic assembly generally comprises a circuit board 20', a high-speed electric chip 40', a control chip 30', an optoelectronic chip 50' and an optical element 60'. The shell 10' is generally divided into two shells: a first shell 11' and a second shell 12', and the first shell 11' is closer to the heat dissipation area of the optical cage and has a faster heat dissipation speed, and the outer surface thereof is the main heat dissipation surface 111' of the shell 10'. The second shell 12' has a slower heat dissipation speed, and the outer surface thereof is the auxiliary heat dissipation surface 121'. The high-speed electric chip 40' and the control chip 30' are arranged on the circuit board 20', and the optoelectronic chip 50' is generally arranged on a high-thermal-conductivity heat sink 70', and is electrically connected to the circuit board 20' through a bonding wire or the like.

[0003] With the increasing density of the module, from the original single channel, to 4 channels, to 8 channels, the components are also multiplied. The components that need to be placed on the circuit board 20' are increasing, and the high-speed signal lines 21' in the circuit board 20' are also increasing, many of which need to be routed in the inner layer, and the inner layer routing needs two reference grounds (GND) and a signal layer, which occupies a large space for routing. For the main high-speed electric chip 40', the power consumption will be high, so it is generally placed on the side of the circuit board 20' close to the main heat dissipation surface 111' of the module shell 10', and the heat dissipation path is shown by the dashed arrow in the figure. However, with the increase of components, the chips with high power consumption are placed on the same side, which greatly increases the complexity of the routing, and a large number of conductive vias 22' are needed, and in high-speed interconnection, the conductive vias 22' are prone to deteriorate the signal quality and reduce the high-frequency performance. Similarly, when the high-speed signal lines 21' are on the side of the circuit board 20' close to the main heat dissipation surface 111' of the shell 10' (the first shell 11'), the side of the optoelectronic chip 50' that is wire-bonded needs to face the main heat dissipation surface 111' to be electrically connected to the high-speed signal lines 21' through wire bonding, so the heat sink 70 needs to be arranged between the optoelectronic chip 50' and the auxiliary heat dissipation surface 121' (the second shell 12') of the shell 10' to conduct the heat of the optoelectronic chip 50' to the auxiliary heat dissipation surface 121', and dissipate the heat from the auxiliary heat dissipation surface 121', so that the heat dissipation speed of the optoelectronic chip 50' is slow. SUMMARY

[0004] The present application aims to provide an optical module packaging structure which can effectively improve the heat dissipation performance and high-frequency performance of the optical module.

[0005] In order to achieve one of the above-mentioned purposes, the application provides an optical module packaging structure, comprising a shell, a circuit board and at least one first device packaged in the shell, the shell comprising a first shell and a second shell, the outer surface of the first shell being a main heat dissipation surface; a sub-board is further arranged in the shell, and the first device is electrically connected to the circuit board through the sub-board;

[0006] The surface of the circuit board is provided with a first signal line, and the surface of the sub-board is provided with an extension segment of the first signal line; the surface of the sub-board provided with the extension segment of the first signal line is partially overlapped and connected with the surface of the circuit board provided with the first signal line, and the first signal line on the circuit board is electrically connected with the extension segment on the sub-board; the surface of the sub-board where the extension segment is located is opposite to the surface of the circuit board where the first signal line is located, and the first device is electrically connected to the extension segment on the sub-board;

[0007] The first device has a heat dissipation surface, which is directed to and thermally connected to the first shell.

[0008] As a further improvement of the embodiment, the circuit board comprises a first surface and a second surface opposite to each other, the first surface of the circuit board is directed to the first shell, and the second surface is directed to the second shell; the first signal line is located on the second surface;

[0009] The sub-board has a third surface and a fourth surface opposite to each other, the extension segment is located on the third surface, and the third surface is partially overlapped and connected with the second surface;

[0010] The third surface is further provided with a solder pad, the solder pad is electrically connected to the extension segment, and the first device is soldered on the solder pad.

[0011] As a further improvement of the embodiment, a thermally conductive pad is arranged between the heat dissipation surface of the first device and the inner surface of the first shell, and the thermally conductive pad is thermally connected to the first device and the first shell.

[0012] As a further improvement of the embodiment, the circuit board comprises a first surface and a second surface opposite to each other, the first surface of the circuit board is directed to the first shell, and the second surface is directed to the second shell; the first signal line is located on the first surface;

[0013] The sub-board has a third surface and a fourth surface opposite to each other, the extension segment is located on the fourth surface, and the fourth surface is partially overlapped with the first surface;

[0014] The first device is electrically connected to the extension segment through a bonding lead or a conductive substrate.

[0015] As a further improvement of the embodiment, the housing further comprises a heat sink, which is in thermal contact with the inner surface of the first housing; and the heat dissipation surface of the first device is in thermal contact with the heat sink.

[0016] As a further improvement of the embodiment, the first device is mounted on the heat sink.

[0017] As a further improvement of the embodiment, the heat sink is fixed on the inner surface of the first housing; or the heat sink is integrally formed with the first housing.

[0018] As a further improvement of the embodiment, the sub-board is at least partially arranged on the heat sink.

[0019] As a further improvement of the embodiment, one end of the circuit board is provided with an electrical interface, one end of the first signal line is electrically connected to the electrical interface, and the other end of the first signal line is welded to the extension section on the sub-board.

[0020] As a further improvement of the embodiment, the circuit board is a hard circuit board; and the sub-board is a hard conductive substrate.

[0021] As a further improvement of the embodiment, the first signal line is used for transmitting high-frequency signals, and the first device is a high-frequency device.

[0022] As a further improvement of the embodiment, the first device comprises one or a combination of a laser, an optical detector, a driver, a signal amplifier, or a silicon optical chip.

[0023] As a further improvement of the embodiment, the housing further comprises a second device and an electronic component;

[0024] The first surface of the circuit board is further provided with a second signal line, the second device is arranged on the first surface, and the second device is electrically connected to the second signal line.

[0025] The electronic component is arranged on the first surface and / or the second surface of the circuit board, or the electronic component is arranged on the sub-board.

[0026] The beneficial effects of the present application are as follows: by increasing the interconnection between the sub-board and the circuit board, on the one hand, most of the devices can be cooled through the main heat dissipation surface of the optical module housing, effectively improving the heat dissipation performance of the module; on the other hand, the wiring space of the circuit board is improved, the via wiring is reduced, and the high-frequency performance of the module is improved. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 It is a schematic diagram of a conventional optical module;

[0028] Figure 2FIG. 1 is a schematic diagram of a conventional optical module package structure;

[0029] Figure 3 FIG. 2 is a schematic diagram of an optical module package structure according to an embodiment of the present application;

[0030] Figure 4 FIG. 3 is a schematic diagram of a top view of components in the optical module package structure according to the embodiment 1 of the present application;

[0031] Figure 5 FIG. 4 is a schematic diagram of a top view of a modified structure of components in the optical module package structure according to the embodiment 1 of the present application;

[0032] Figure 6 FIG. 5 is a schematic diagram of a top view of another modified structure of components in the optical module package structure according to the embodiment 1 of the present application;

[0033] Figure 7 FIG. 6 is a schematic diagram of an optical module package structure according to another embodiment of the present application;

[0034] Figure 8 FIG. 7 is a schematic diagram of a bottom view of components in the optical module package structure according to the embodiment 2 of the present application;

[0035] Figure 9 FIG. 8 is a schematic diagram of a top view of components in the optical module package structure according to the embodiment 3 of the present application;

[0036] Figure 10 FIG. 9 is a schematic diagram of a bottom view of components in the optical module package structure according to the embodiment 3 of the present application. DETAILED DESCRIPTION

[0037] The present application will be described in detail with reference to the drawings, which show specific embodiments of the present application. However, these embodiments are not intended to limit the present application, and any modifications in structure, method, or function made by those skilled in the art based on these embodiments are included in the scope of the present application.

[0038] In each of the drawings of the present application, some dimensions of structures or parts are exaggerated relative to other structures or parts for the purpose of illustration, and thus, are used only to illustrate the basic structure of the subject matter of the present application.

[0039] Additionally, terms such as “above,” “over,” “below,” and “under,” used herein to indicate spatial relative position, are for illustrative purposes to describe the relationship of one unit or feature relative to another unit or feature as shown in the accompanying drawings. The terms of spatial relative position may be intended to include different orientations of the device in use or operation other than those shown in the figures. For example, if the device in the figures is flipped, a unit described as being “below” or “under” another unit or feature would be “above” that unit or feature. Therefore, the exemplary term “below” can encompass both above and below orientations. The device may be oriented in other ways (rotated 90 degrees or otherwise) and the spatially related descriptive terms used herein shall be interpreted accordingly. When an element or layer is referred to as being “on” or “connected” to another component or layer, it may be directly on or connected to that other component or layer, or there may be intermediate elements or layers present.

[0040] Example 1

[0041] like Figure 3 and 4 The optical module packaging structure shown is an embodiment of this application. The optical module packaging structure 100 includes a housing 10, a circuit board 20 encapsulated within the housing 10, and at least one first device 40, the first device 40 having a heat dissipation surface 41. The housing 10 includes a first housing 11 and a second housing 12, wherein the outer surface of the first housing 11 is a main heat dissipation surface 111, and the outer surface of the second housing 12 is a secondary heat dissipation surface 121. The main heat dissipation surface 111 dissipates heat faster. Here, we take the example of the main heat dissipation surface 111 facing upwards and the secondary heat dissipation surface 121 facing downwards. In reality, the optical module packaging structure 100 can be flipped upside down, causing the relative positions of the main heat dissipation surface 111 and the secondary heat dissipation surface 121 to be reversed. A sub-board 80 is also provided inside the housing 10. The first device 40 is electrically connected to the circuit board 20 via the sub-board 80, ensuring that the heat dissipation surface 41 of the first device 40 faces the first housing 11 and is thermally connected to the inner surface of the first housing 11. This allows the heat from the first device 40 to dissipate through the main heat dissipation surface 111 of the first housing 11, thereby improving heat dissipation efficiency. Here, the circuit board 20 is a rigid PCB (Printed Circuit Board), and the sub-board 80 is a rigid conductive substrate. This rigid conductive substrate can be a conductive ceramic substrate, silicon substrate, glass substrate, or resin substrate, or it can be the same rigid PCB as the circuit board 20.

[0042] The surface of the circuit board 20 is provided with a first signal line 23, and the surface of the sub-board 80 is provided with an extension segment 83 of the first signal line. The surface of the sub-board 80 provided with the extension segment 83 of the first signal line partially overlaps the surface of the circuit board 20 provided with the first signal line 23, so as to connect the first signal line 23 on the circuit board 20 to the extension segment 83 on the sub-board 80. The surface of the sub-board 80 and the surface of the circuit board 20 partially overlap in opposite directions, and the first device 40 is electrically connected to the extension segment 83 on the sub-board 80. The sub-board 80 and the circuit board 20 can be fixed together by welding or adhesive bonding. One end of the circuit board 20 is provided with an electrical interface 24, such as a gold finger, and one end of the first signal line 23 is electrically connected to the electrical interface 24, and the other end is welded to the extension segment 83 on the sub-board 80, or the extension segment 83 on the sub-board 80 and the first signal line 23 on the circuit board 20 can be attached together by surface mounting technology (SMT) to electrically connect the extension segment 83 and the first signal line 23. The first signal line 23 is used to transmit high-frequency signals, and the first device 40 is a high-frequency device, which can be one or a combination of a laser, an optical detector, a driver, a signal amplifier, or a silicon optical chip. The housing 10 has an electrical port 13 and an optical port 14, and the electrical interface 24 of the circuit board 20 extends out of the electrical port 13 of the housing 10 to achieve electrical connection with the outside, and the optical port 14 of the housing 10 is used to transmit optical signals.

[0043] The circuit board 20 has a first surface 21 and a second surface 22 facing away from each other, wherein the first surface 21 faces the first housing 11 and the second surface 22 faces the second housing 12, and the first signal line 23 is located on the second surface 22. The first surface 21 and the second surface 22 of the circuit board 20 are both provided with an electrical interface 24, the first signal line 23 is connected to the electrical interface 24 on the second surface 22, and the first surface 21 is also provided with a second signal line 25 for transmitting signals, and a second device 30 electrically connected to the second signal line 25, the second signal line 25 is connected to the electrical interface 24 on the first surface 21, and is used for signal transmission between the electrical interface 24 and the second device 30. The first signal line 23 is connected to the electrical interface 24 on the second surface 22, and is used for signal transmission between the electrical interface 24 and the first device 40. The second signal line 25 is also a high-frequency signal line, and the second device 30 is a high-frequency device, which can also be one or a combination of a laser, an optical detector, a driver, a signal amplifier or a silicon optical chip. That is, the first device 40 and the second device 30 are one or a combination of a laser, an optical detector, a driver, a signal amplifier or a silicon optical chip. Generally, the first device 40 and the second device 30 are different devices, and the number of each can be one, two or more. The first device 40 refers to a device electrically connected to the electrical interface 24 on the second surface 22 of the circuit board 20 through the first signal line 23, and the second device 30 refers to a device electrically connected to the electrical interface 24 on the first surface 21 of the circuit board 20 through the second signal line 25. The first device 40 is usually soldered to the second surface 22 of the circuit board 20, and has low heat dissipation efficiency, or is soldered to the first surface 21 of the circuit board 20, and the first signal line 23 is electrically connected to the first device 40 through a conductive via. The use of a conductive via affects the high-frequency performance. The second device 30 is usually soldered to the first surface 21 of the circuit board 20, and its heat dissipation surface faces the first housing 11, so that heat can be dissipated through the main heat dissipation surface 111 of the first housing 11, and the heat dissipation path is as shown by the dashed arrow in the middle of the figure, and the heat dissipation speed is fast. Figure 3

[0044] ​The sub-board 80 has a third surface 81 and a fourth surface 82 facing away from each other. An extension 83 of the first signal line 23 is located on the third surface 81, which partially overlaps with the second surface 22 of the circuit board 20, such that one end of the extension 83 is soldered to one end of the first signal line 23. In this embodiment, the sub-board 80 can be partially soldered to the second surface 22 of the circuit board 20 using surface mount technology, so that the extension 83 on the sub-board 80 is electrically connected to the first signal line 23 on the second surface 22 of the circuit board 20, thereby extending the first signal line 23 facing away from the first housing 11 into an extension 83 facing the first housing 11. The third surface 81 of the sub-board 80 is also provided with a pad (not shown in the figure), which is electrically connected to the extension 83. For example, a pad is provided at the end of the extension 83. The first device 40 is soldered to the pad 34, so that the first device 40, which is normally facing away from the first housing 11 and soldered to the second surface 22 of the circuit board 20 to be electrically connected to the first signal line 23, is flipped so that the heat dissipation surface 41 of the first device 40 faces the first housing 11, and heat is dissipated through the main heat dissipation surface 111 of the first housing 11. The heat dissipation path is as follows. Figure 3 As indicated by the dashed arrow, heat dissipation efficiency is effectively improved. Furthermore, the first signal line 23 on the second surface 22 of the circuit board 20 does not require conductive vias to penetrate the first surface 21, reducing the impact of via routing on high-frequency signals, improving the routing space of the circuit board 20, and enhancing the high-frequency performance of the module. In other embodiments, the daughter board can also be soldered to the second surface of the circuit board using Ball Grid Array (BGA) technology. In this embodiment, the daughter board 80 also has a ground line 84, and the first device 40 is electrically connected to this ground line 84. The ground line 84 is electrically connected to the ground line on the circuit board 20 (not shown in the figure), and the connection method is the same as the connection between the first signal line 23 and the extension 83. In other embodiments, the first device 40 may not be directly connected to the ground line, or it may be connected to other signal lines.

[0045] In this embodiment, the circuit board 20 can also be provided with electronic components, such as capacitors, inductors, resistors, etc., or other electric chips that generate less heat. These electronic components can be provided on the first surface 21 and / or the second surface 22 of the circuit board 20. In other embodiments, other electronic components can also be provided on the third surface and / or the fourth surface of the sub-board. For example, in an optical transceiver module, optical elements and optoelectronic chips (not shown in the figure) are provided near the optical port 14 of the housing 10. The optical elements can be one or a combination of coupling lenses, collimating lenses, wavelength division multiplexers, optical sockets, optical fibers, etc. The optoelectronic chips can be lasers and photodetectors, or silicon optical chips, etc. The second device 30, such as a signal amplifier, is provided on the first surface 21 of the circuit board 20. The first device 40, such as a driver, is soldered to the aforementioned pads on the third surface 81 of the sub-board 80, and is electrically connected to the extension section 83 of the first signal line 23. The optical signal received at the optical port 14 of the optical module packaging structure 100 is coupled to the photodetector through the optical elements, and is converted into an electrical signal by the photodetector and transmitted to the circuit board 20. After being amplified by the signal amplifier (second device 30), the electrical signal is transmitted to other processors or to the outside of the optical module packaging structure 100 through the electrical interface 24 of the circuit board 20. The electrical signal received at the electrical port 13 of the optical module packaging structure 100 is processed by the processor on the circuit board 20, and is then transmitted to the driver (first device 40) on the sub-board 80 through the first signal line 23 of the second surface 22. The driver drives the laser to work, and the laser emits an optical signal, which is transmitted out of the optical port 14 of the optical module packaging structure 100 through the optical elements. In this way, the second device 30, such as a signal amplifier, which is electrically connected to the second signal line 25 of the first surface 21 of the circuit board 20, can be directly soldered to the first surface 21 of the circuit board 20, and can be cooled by the main heat dissipation surface 111 of the first housing 11. The first device 40, which is electrically connected to the first signal line 23 of the second surface 22, can be extended to the extension section 83 of the sub-board 80 towards the pads on the third surface 81 of the first housing 11, so that the first device 40, such as a driver, which is electrically connected to the first signal line 23 of the second surface 22, can be soldered to the pads on the third surface 81 of the sub-board 80, and the heat dissipation surface 41 of the first device 40 is also directed towards the first housing 11, so that the first device 40 can be cooled by the main heat dissipation surface 111 of the first housing 11, improving the heat dissipation efficiency. Moreover, the extension section 83 extending from the first signal line 23 to the sub-board 80 does not need to pass through the circuit board 20 through a conductive via, reducing the influence of the conductive via on high-frequency signals, improving the wiring space of the circuit board, and improving the high-frequency performance of the module.

[0046] In this embodiment, thermal pads 72 and 71 are also provided between the heat dissipation surface 41 of the first device 40 and the heat dissipation surface of the second device 30 on the first surface 21 of the circuit board 20 and the inner surface of the first housing 11, respectively, to thermally connect the first device 40 and the first housing 11, and to thermally connect the second device 30 and the first housing 11, thereby accelerating the heat dissipation speed between the first device 40 and the second device 30 and the first housing 11, and further improving the heat dissipation efficiency of the optical module.

[0047] like Figure 4 The diagram shown is a top view of the components within the optical module packaging structure 100. In this embodiment, the circuit board 20 has a notch at the other end opposite its electrical interface 24, and one end of the daughter board 80 is soldered to the notch along the length of the circuit board 20. A first signal line extends along the length of the circuit board 20 onto the daughter board 80. In other embodiments, such as... Figure 5 As shown, in this embodiment, the other end of the circuit board 20 opposite to its electrical interface 24 also has a notch, and one end of the daughter board 80 is soldered to the notch of the circuit board 20 along the width extension direction of the circuit board 20. The first signal line extends onto the daughter board 80 along the width extension direction of the circuit board 20. Figure 6 As shown, with Figure 4 and 5 Unlike the illustrated embodiment, in this embodiment, the circuit board 20 has no notch, and the sub-board 80 is directly soldered to the other end of the circuit board 20 opposite to its electrical interface 24. Both first signal lines on the second surface of the circuit board 20 extend to the third surface 81 of the sub-board 80. The third surface 81 of the sub-board 80 has extensions 83 of the two first signal lines, two first devices 40, and two ground lines 84. The two first devices 40 are respectively soldered to the pads of the two extensions 83. These two first devices 40 can be two identical devices, such as two drivers, or two different devices, such as one driver and one signal amplifier. Similarly, Figure 4 and 5 In the illustrated embodiment, the number of first devices 40 can also be two or more. The specific shape of the circuit board can be designed according to the actual circuit routing needs, and appropriate positions can be selected for soldering sub-boards. The specific shape of the circuit board and the position of the soldered sub-boards are not limited by the illustrations, and different modifications are all within the protection scope of this application.

[0048] Example 2

[0049] like Figure 7 and 8The light module package structure 200 shown is another embodiment of the present application, which is different from the embodiment 1 in that the first device 50 in this embodiment is electrically connected to the pads of the extension section 93 on the sub-board 90 through bonding wires or other conductive elements. The first signal line 26 on the circuit board 20, which is electrically connected to the first device 50, is located on the first surface 21 of the circuit board 20. The first signal line 26 is electrically connected to the electrical interface 24 on the first surface 21 of the circuit board 20, and is used for signal transmission between the electrical interface 24 on the first surface 21 of the circuit board 20 and the first device 50. For example, the light detector, laser or silicon optical chip, etc. as the first device 50, is usually electrically connected to the first signal line 26 on the first surface 21 of the circuit board 20 through bonding wires. The pads of the first device 50 are usually in the same direction as the first surface 21 of the circuit board 20, and face the first housing 11, so that the heat dissipation surface 51 faces the second housing 12, and is cooled through the auxiliary heat dissipation surface 121 of the second housing 12, with low heat dissipation efficiency. In this embodiment, the first signal line 26 on the first surface 21 of the circuit board 20 is extended to the extension section 93 on the fourth surface 92 of the sub-board 90 through the sub-board 90. The first device 50 is electrically connected to the pads of the extension section 93 on the sub-board 90 through bonding wires 94 or other means, so that the first device 50 with the heat dissipation surface 51 usually facing the second housing 12 is flipped, with the heat dissipation surface 51 facing the first housing 11, and is cooled through the main heat dissipation surface 111 of the first housing 11, so as to improve the heat dissipation efficiency.

[0050] Specifically, the first surface 21 of the circuit board 20 faces the first housing 11, and the second surface 22 faces the second housing 12; the first signal line 26 is located on the first surface 21. The sub-board 90 has a third surface 91 and a fourth surface 92 opposite to each other, the third surface 91 faces the first housing 11, and the fourth surface 92 is opposite to the first surface 21 of the circuit board 20. The extension segment 93 and its pads are located on the fourth surface 92, and the fourth surface 92 partially overlaps the first surface 21. The sub-board 90 is partially soldered to the first surface 21 of the circuit board 20 by surface mounting technology or ball grid array technology, i.e., the fourth surface 92 of the sub-board 90 partially overlaps the first surface 21 of the circuit board 20, so that one end of the extension segment 93 is soldered to one end of the first signal line 26, thereby extending the first signal line 26 on the first surface 11 of the circuit board 20 to the extension segment 93 on the fourth surface 62 of the sub-board 90. The first device 50 is electrically connected to the pads of the extension segment 93 on the sub-board 90 by the bonding wire 94 or the conductive substrate, etc. The first device 50 is located beside the sub-board 90, and its pads are in the same direction as the fourth surface 92 of the sub-board 90, both facing the second housing 12; and its heat dissipation surface 51 faces the first housing 11, and can be heat-dissipated from the main heat dissipation surface 111 of the first housing 11, effectively improving the heat dissipation efficiency. As in the embodiment 1, in this embodiment, the extension segment 93 extending from the first signal line 26 to the fourth surface 92 of the sub-board 90 does not need to pass through the circuit board 20 through the conductive via, reducing the influence of the via wiring on the high-frequency signal, improving the wiring space of the circuit board, and improving the high-frequency performance of the module.

[0051] In this embodiment, a heat sink 70 is also provided in the housing 10, which is in thermal contact with the inner surface of the first housing 11. The heat dissipation surface 51 of the first device 50 is in thermal contact with the heat sink 70. An optical element 60, such as a coupling lens, a collimating lens, a wavelength division multiplexer, an optical receptacle, an optical fiber or a combination of one or more of them, is also provided between the first device 50 and the optical port 14 of the housing 10. Specifically, the first device 50 is mounted on the heat sink 70, and the heat sink 70 is fixed to the inner surface of the first housing 11 by means of a heat dissipation adhesive. In other embodiments, the heat sink 70 can be integrally formed with the first housing 11. In this embodiment, the sub-board 90 is at least partially fixed to the heat sink 70 by means of adhesion, and the first device 50 is located near the sub-board 90, at one end or one side of the sub-board 90. When the first device 50 is a laser, the laser is provided on a substrate, and the substrate is fixed to the heat sink 70, or the substrate is fixed to the heat sink 70 through an insulating and heat-conducting pad, such as aluminum nitride ceramic. In this embodiment, the heat sink 70 also serves as a carrier plate for carrying the optical element 60, i.e. the optical element 60 is mounted on the heat sink 70. In other embodiments, the optical element 60 can also be mounted on another carrier plate. In this embodiment, the circuit board 20 can also be provided with electronic elements 31, such as capacitors, inductors, resistors and other electric chips that generate less heat. These electronic elements 31 can be provided on the first surface 21 and / or the second surface 22 of the circuit board 20.

[0052] In this embodiment, the specific shape of the circuit board can be designed according to the actual circuit layout requirements, and the sub-boards can be welded at appropriate positions. The specific shape of the circuit board and the position of the welded sub-boards are not limited by the drawings, and different modifications are within the scope of protection of the present application.

[0053] Embodiment 3

[0054] Figure 9 Fig. 3 is a top view of the components of the optical module packaging structure of this embodiment, Figure 10 Fig. 4 is a bottom view of the components of the optical module packaging structure of this embodiment, in which the housing is omitted. Like in Embodiments 1 and 2, the first housing and its main heat dissipation surface are located at the top, and the second housing and its auxiliary heat dissipation surface are located at the bottom. Unlike Embodiments 1 and 2, this embodiment is provided with two sub-boards, a first sub-board 80 (same as the sub-board 80 of Embodiment 1) and a second sub-board 90 (same as the sub-board 90 of Embodiment 2). The first sub-board 80 is welded with the first device 40, and the second sub-board 90 is electrically connected to another first device 50 through the bonding wire 94. That is, this embodiment is equivalent to a combination of the structures of Embodiments 1 and 2, for example, the optical detector (i.e. the first device 40) is welded on the first sub-board 80, and the laser (i.e. the first device 50) is provided beside the second sub-board 90, and the laser and the second sub-board 90 are electrically connected through the bonding wire 94.

[0055] Specifically, the second surface 22 of the circuit board 20 in this embodiment is provided with a first signal line 23, which extends to an extension section 83 on the third surface 81 of a first sub-board 80 (same as the sub-board 80 in Embodiment 1). The third surface 81 of the first sub-board 80 is provided with a first device 40, which is electrically connected to the extension section 83 by soldering, thereby electrically connecting the first signal line 23 on the second surface 22 of the circuit board 20 through the extension section 83. Thus, the first device 40, which is normally soldered on the second surface 22 of the circuit board 20, can be flipped and soldered on the third surface 81 of the first sub-board 80, so that the heat dissipation surface of the first device 40 faces the first housing, and thus can dissipate heat from the main heat dissipation surface of the first housing, thereby improving the heat dissipation efficiency.

[0056] Meanwhile, the first surface 21 of the circuit board 20 is also provided with a first signal line 26, which extends to an extension section 93 on the fourth surface 92 of a second sub-board 90 (same as the sub-board 90 in Embodiment 2). The first device 50 is provided near one side or end face of the second sub-board 90, which is electrically connected to the extension section 93 on the second sub-board 90 through a bonding wire 94, thereby electrically connecting the first signal line 26 on the first surface 21 of the circuit board 20 through the extension section 93 on the second sub-board 90. Thus, the first device 50, which is normally provided beside the circuit board 20 and electrically connected to the first surface 21 of the circuit board 20 through the bonding wire, can be flipped and electrically connected to the fourth surface 92 of the second sub-board 90 through the bonding wire, so that the heat dissipation surface of the first device 50 faces the first housing, and thus can dissipate heat from the main heat dissipation surface of the first housing, thereby improving the heat dissipation efficiency.

[0057] In this embodiment, the circuit board 20 can also be provided with electronic components 31, such as capacitors, inductors, resistors, etc., or other electric chips that generate less heat. These electronic components 31 can be provided on the first surface 21 and / or the second surface 22 of the circuit board 20.

[0058] The structure of this embodiment can ensure that the heat dissipation surfaces of the first devices 40, 50 of different connection modes (such as soldering or wire bonding, etc.) all face the first housing, and the main heat dissipation path is the main heat dissipation surface of the first housing, thereby quickly dissipating heat and effectively improving the heat dissipation efficiency.

[0059] The above series of detailed descriptions are only specific descriptions of the feasible embodiments of the present application, and are not intended to limit the protection scope of the present application. Any equivalent embodiments or changes made without departing from the spirit of the present application should be included in the protection scope of the present application.

Claims

1. An optical module package structure, characterized by, The application relates to a circuit board, a heat sink, a first device, a sub-board and a housing. The circuit board comprises a first surface and a second surface, the first surface is provided with a first signal line; The heat sink; The first device is arranged on the heat sink, the surface of the first device away from the heat sink is provided with a pad, the pad is in the same direction as the second surface; The sub-board is partially overlapped with the first surface of the circuit board and is welded and fixed with the circuit board; The surface of the sub-board towards the circuit board is provided with an extension of the first signal line, one end of the extension is electrically connected with the first signal line on the circuit board, and the other end is adjacent to the first device and is electrically connected with the pad of the first device through a bonding wire or a conductive substrate.

2. The optical module package structure according to claim 1, characterized in that: The side of the sub-board away from the circuit board is at least partially overlapped with the heat sink.

3. The optical module package structure of claim 1, wherein: The part of the sub-board overlapped with the circuit board is welded and fixed with the circuit board through a ball grid array technology or a surface mount technology, so that the extension of the first signal line on the sub-board is electrically connected with the first signal line on the circuit board.

4. The optical module package structure of claim 1, wherein: The first device is a laser, and the first signal line and the extension are used for transmitting a high-frequency signal.

5. The optical module package structure according to claim 4, characterized in that: The laser is arranged on a substrate, and the substrate is fixed on the heat sink or the substrate is fixed on the heat sink through an insulating heat-conducting pad.

6. The optical module package structure of claim 4, wherein: The application further comprises a second device, the second device is arranged on the first surface of the circuit board; the first surface of the circuit board is further provided with a second signal line, and the second device is electrically connected with the second signal line.

7. The optical module package structure of claim 1, wherein: The first surface of the circuit board is further provided with an electric chip.

8. The optical module package structure according to claim 7, characterized by: The application further comprises a housing, the housing has an electric port and an optical port, the circuit board, the sub-board, the heat sink and the first device are arranged in the housing, one end of the circuit board is provided with an electric interface, the electric interface extends out of the electric port of the housing to be electrically connected with the outside, and the optical port is used for transmitting an optical signal.

9. The optical module package structure of claim 8, wherein: An optical element is arranged between the first device and the optical port, the optical element comprises one or a combination of a coupling lens, a collimating lens, a wavelength division multiplexer, an optical socket and an optical fiber.

10. The optical module package structure of claim 8, wherein: The housing comprises a first housing and a second housing, the first surface of the circuit board faces the first housing, and the electric chip and the heat sink are in heat-conducting connection with the first housing.

11. The optical module package structure according to any one of claims 1-10, wherein: The first signal line of the first surface comprises a plurality of first signal lines, the first device comprises a plurality of first devices, and the extension on the sub-board comprises a plurality of extensions, and the plurality of first devices, the plurality of extensions and the plurality of first signal lines correspond to each other one by one.

12. The optical module package structure according to any one of claims 1-10, wherein: The circuit board is a hard circuit board, and the sub-board is a hard conductive substrate.

13. An optical module package structure, characterized by comprising: The application relates to a circuit board, a heat sink, a first device, a sub-board and a housing. The circuit board comprises a first surface and a second surface, the first surface and the second surface are both provided with a high-frequency signal line; The first sub-board is partially overlapped with the second surface of the circuit board; A second sub-board, which is partially stacked on the first surface of the circuit board; the second sub-board is provided with an extension of high-frequency signal line towards the surface of the circuit board; one end of the extension on the second sub-board is electrically connected with the high-frequency signal line on the first surface; At least two first devices, one of which is welded on the first sub-board to electrically connect the extension on the first sub-board and the high-frequency signal line on the second surface of the circuit board through the extension on the first sub-board; the other is arranged beside the second sub-board and is electrically connected with the extension on the second sub-board through a bonding wire to electrically connect the high-frequency signal line on the first surface of the circuit board through the extension.

14. The optical module packaging structure according to claim 13, characterized in that: The part of the first sub-board stacked on the circuit board is welded and fixed to the circuit board by ball grid array technology or surface mount technology, so that the extension on the first sub-board is electrically connected with the high-frequency signal line on the circuit board; The part of the second sub-board stacked on the circuit board is welded and fixed to the circuit board by ball grid array technology or surface mount technology, so that the extension on the second sub-board is electrically connected with the high-frequency signal line on the circuit board.

15. The optical module package structure of claim 13, wherein: Further comprising a heat sink, which is located on the side of the second sub-board away from the circuit board; the heat sink is partially fixed with the second sub-board and partially extends out of the second sub-board to mount the first device arranged beside the second sub-board.

16. The optical module package structure of claim 15, wherein: Further comprising a housing, which comprises a first housing and a second housing; the circuit board, the first sub-board, the second sub-board, the first device and the heat sink are located in the housing; the first surface of the circuit board faces the first housing; the heat sink is in thermal contact with the first housing; the first device mounted on the heat sink is in thermal contact with the heat sink.

17. The optical module package structure of claim 16, wherein: The first device welded on the first sub-board is welded on the surface of the first sub-board provided with the extension and has a heat dissipation surface away from the first sub-board, which is in thermal contact with the first housing.

18. The optical module package structure of claim 16, wherein: One end of the circuit board is provided with an electrical interface; the housing has an electrical port and an optical port; the electrical interface of the circuit board extends out of the electrical port of the housing to be electrically connected with the outside; the optical port is used to transmit optical signals.

19. The optical module package structure of claim 16, wherein: The first surface of the circuit board is further provided with an electrical chip, which is in thermal contact with the first housing.

20. The optical module package structure of claim 18, wherein: An optical element is arranged between the first device on the heat sink and the optical port; the optical element comprises one or a combination of coupling lens, collimating lens, wavelength division multiplexer, optical socket and optical fiber.

21. The optical module package structure of any of claims 13-20, wherein: The circuit board is a hard circuit board; the sub-boards are hard conductive substrates.

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