CN217655318U

CN217655318U - Optical module packaging structure and optical module

Info

Publication number: CN217655318U
Application number: CN202221601854.1U
Authority: CN
Inventors: 方文银; 彭开盛
Original assignee: Tri Light Wuhan Electronics Technology Co ltd
Current assignee: Tri Light Wuhan Electronics Technology Co ltd
Priority date: 2022-06-24
Filing date: 2022-06-24
Publication date: 2022-10-25
Anticipated expiration: 2032-06-24

Abstract

The utility model discloses an encapsulated structure and optical module of optical module, this encapsulated structure include fiber array, PCBA and base plate, PCBA is equipped with the through-hole, fiber array's substrate and PCBA's one side fixed connection to cover PCBA's through-hole completely, base plate and PCBA's another side fixed connection to cover PCBA's through-hole completely, form airtight chamber between fiber array, PCBA, base plate, set up the optical chip on the base plate, the optical chip is located airtight intracavity, be provided with lens on fiber array's the substrate, lens are located airtight intracavity, lens and the optical chip one-to-one from top to bottom. Adopt above-mentioned scheme, make the utility model discloses an optical chip, lens and optical chip and the light path between the lens all are located airtight chamber, reach the purpose of gas tightness encapsulation, do not receive external liquid to disturb, can be applied to in the liquid cooling environment.

Description

Optical module packaging structure and optical module

Technical Field

The utility model belongs to the technical field of the optical communication, concretely relates to packaging structure and optical module of optical module.

Background

At present, most optical modules used in data center communication are metal-packaged air-cooled optical modules, that is, cooling systems are all air-cooled, and a cooling medium is air. However, as the power consumption of the optical module is larger and larger, the air cooling is more and more difficult to meet the heat dissipation requirement of the module with larger power consumption; meanwhile, in order to save energy and protect environment, enterprises such as Google, facebook and ali are actively developing liquid refrigeration optical modules, and it is desired to replace air cooling with cooling liquid.

The use of liquid immersion cooling technology in data centers and high performance computing has become a trend, and in order to meet this trend, it is necessary to develop a light module that can be used directly in liquid. The conventional optical module generally adopts an alloy tube shell, the optical element adopts a non-airtight packaging mode, and the optical connector is directly exposed; when the optical module is directly arranged in a liquid cooling environment, the refrigerant liquid can easily permeate into the optical path of the optical element due to the strong permeability of the refrigerant liquid, so that the optical path is affected, and unpredictable optical reflection, refraction and the like are caused. Therefore, the conventional optical module is difficult to work normally in a liquid cooling environment, and how to effectively protect the optical path of the optical module is a problem which needs to be solved by the optical module applied to the liquid cooling environment.

The patent with the application number of CN201910891292.5 provides an optical module capable of adopting liquid immersion type refrigeration and a manufacturing method thereof, COB packaging is adopted in an optoelectronic part, the whole optical module adopts low-pressure injection molding materials to carry out full-plastic packaging design, a circuit and a circuit are all wrapped in a plastic packaging body, complete isolation of an optoelectronic device inside the module and external liquid is achieved, however, low-pressure injection molding is adopted, an additional injection molding machine is needed, and the long-term use reliability of plastics in liquid cooling liquid (fluorine oil) is poor.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to overcome prior art's defect, provide an optical module's packaging structure and optical module, it realizes the gas tightness encapsulation, can be applied to in the liquid cooling environment.

The technical scheme of the utility model is realized like this: the utility model discloses an encapsulation structure of optical module, including fiber array, PCBA and base plate, PCBA is equipped with the through-hole, fiber array and PCBA's one side fixed connection to cover PCBA's through-hole completely, base plate and PCBA's another side fixed connection to cover PCBA's through-hole completely, form airtight chamber between fiber array, PCBA, base plate, set up the optical chip on the base plate, the optical chip is located airtight intracavity.

Further, the optical fiber array and the PCBA are fixedly connected in an airtight welding mode.

Furthermore, the optical fiber array is provided with lenses, the lenses are positioned in the airtight cavity, and the lenses and the optical chips are in one-to-one correspondence from top to bottom.

Furthermore, the lower terminal surface of the optical fiber array substrate is provided with an annular metal layer, the lens is positioned in the annular metal layer of the optical fiber array substrate, the upper end surface of the PCBA is provided with a first annular metal layer, the through hole of the PCBA is positioned in the first annular metal layer, and the first annular metal layer of the upper end surface of the PCBA and the annular metal layer of the optical fiber array substrate are welded and fixed to form airtight packaging.

Further, the base plate and the PCBA are fixedly connected in an airtight welding mode.

Further, the base plate is insulating substrate, the up end of base plate is equipped with the annular metal layer, the optical chip is located the annular metal layer of base plate, PCBA's lower terminal surface is equipped with second annular metal layer, and PCBA's through-hole is located the second annular metal layer, and welded fastening forms airtight encapsulation between the annular metal layer of the second annular metal layer of terminal surface and base plate up end under the PCBA.

Furthermore, be equipped with the pad on the up end of base plate, the pad on the base plate passes through the gold wire bonding and is connected with the optical chip electricity, PCBA's lower extreme face is equipped with first pad, first pad on the PCBA corresponds from top to bottom with the pad on the base plate to the welding.

Further, the bonding pad on the substrate is positioned in the annular metal layer.

Further, the first pad is located in the second annular metal layer of the lower end face of the PCBA.

Furthermore, a second pad is arranged on the PCBA, and the second pad is electrically connected with the first pad through an inner layer wire of the PCBA.

Further, the substrate is a ceramic substrate.

Furthermore, the optical fiber array is provided with a reflecting surface, and the reflecting surface is obliquely arranged and used for turning the light path between the optical fiber and the optical chip by 90 degrees.

The utility model also discloses an optical module has adopted as above the packaging structure of optical module.

The utility model discloses following beneficial effect has at least: the utility model discloses a PCBA of optical module is equipped with the through-hole, optical fiber array and PCBA's one side fixed connection to cover PCBA's through-hole completely, base plate and PCBA's another side fixed connection, and cover PCBA's through-hole completely, form airtight chamber between optical fiber array, PCBA, base plate, set up the optical chip on the base plate, the optical chip is located airtight intracavity. The optical fiber array is provided with lenses which are positioned in the airtight cavity, and the lenses are in one-to-one correspondence with the optical chips from top to bottom. Adopt above-mentioned scheme, make the utility model discloses an optical chip, lens and optical chip and the light path between the lens all are located airtight chamber, reach the purpose of gas tightness encapsulation, do not receive external liquid to disturb, can be applied to in the liquid cooling environment.

And this patent adopts the mode of gilding + metallic solder, reaches the purpose of gas tightness encapsulation, and used spare part is the spare part commonly used in the optical communication industry, and the supply chain easily acquires, and production facility is compatible current equipment completely.

Drawings

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

Fig. 1 is a perspective view of an encapsulation structure of an optical module according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of an encapsulation structure of an optical module according to an embodiment of the present invention;

FIG. 3 is a sectional view taken along line B-B of FIG. 2;

fig. 4 is an enlarged view of a portion a of fig. 3.

Fig. 5 is a schematic back view of a PCBA according to an embodiment of the present invention;

fig. 6 is a schematic front view of a PCBA according to an embodiment of the present invention;

fig. 7 is a schematic diagram of an optical fiber array according to an embodiment of the present invention;

fig. 8 is a schematic diagram of a substrate according to an embodiment of the present invention.

In the drawing, 1 is an optical fiber array, 11 is an annular metal layer of the optical fiber array, 12 is a reflective surface, 2 is a PCBA,21 is a through hole, 22 is a first pad, 23 is a second pad, 24 is a first annular metal layer, 25 is a second annular metal layer, 26 is a trace, 3 is a substrate, 31 is a pad of the substrate, 32 is an annular metal layer of the substrate, 4 is an airtight cavity, 5 is an optical chip, and 6 is a lens.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

In the description of the present invention, it is to be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are merely for convenience of description and simplicity of description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, are not to be construed as limiting the present invention.

The terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature; in the description of the present invention, "a plurality" or "a plurality" means two or more unless otherwise specified.

Example one

Referring to fig. 1 to 8, the embodiment of the utility model provides an optical module that can adopt liquid submergence formula to refrigerate, including fiber array 1, PCBA2 and base plate 3, PCBA2 is equipped with through-hole 21, fiber array 1's substrate and PCBA 2's one side fixed connection to cover PCBA 2's through-hole 21 completely, base plate 3 and PCBA 2's another side fixed connection to cover PCBA 2's through-hole 21 completely, form airtight chamber 4 between fiber array 1, PCBA2, base plate 3, set up optical chip 5 on the base plate 3, optical chip 5 is located airtight chamber 4.

The utility model discloses an optical chip can all be and receive optical chip, also can all be and send optical chip, also can some receive optical chip partly and send optical chip (like half receive optical chip and half send optical chip). The number of the optical chips is set according to needs.

The utility model discloses an optical fiber array has an optic fibre at least.

The through hole 21 of the PCBA2 of the present embodiment is a kidney-shaped hole. Of course, the through-hole 21 of the PCBA2 is not limited to the kidney-shaped hole, and may be provided in other shapes as needed.

Furthermore, the substrate of the optical fiber array 1 is provided with lenses 6, the lenses 6 are located in the airtight cavity 4, and the lenses 6 correspond to the optical chips 5 one by one. The number of the lenses corresponds to the number of the optical chips one by one.

The lens 6 of the present embodiment is attached to the optical fiber array 1 by optically transparent glue.

Further, the optical fiber array 1 and the PCBA2 are fixedly connected in an airtight welding mode.

Furthermore, the lower end surface of the optical fiber array 1 substrate is provided with an annular metal layer 11, the lens 6 is positioned in the annular metal layer of the optical fiber array 1 substrate, the upper end surface of the PCBA2 is provided with a first annular metal layer 24, the through hole 21 of the PCBA2 is positioned in the first annular metal layer 24, and the first annular metal layer 24 on the upper end surface of the PCBA2 and the annular metal layer of the optical fiber array 1 substrate are welded and fixed to form airtight packaging. The PCBA2 and the optical fiber array 1 substrate can be fixed by adopting low-temperature metal solder welding. The low temperature metallic solder may be selected from metallic solder flakes or solder paste having a melting point between 118 c and 160 c.

Further, the substrate 3 and the PCBA2 are fixedly connected by means of air-tight welding.

Furthermore, an annular metal layer 32 is arranged on the upper end face of the substrate 3, the optical chip 5 is located in the annular metal layer 32 of the substrate 3, a second annular metal layer 25 is arranged on the lower end face of the PCBA2, the through hole 21 of the PCBA2 is located in the second annular metal layer 25, and the second annular metal layer 25 on the lower end face of the PCBA2 and the annular metal layer on the upper end face of the substrate 3 are welded and fixed to form airtight packaging. The PCBA2 and the substrate 3 can be fixed by low-temperature metal solder.

Further, the substrate 3 is an insulating substrate 3, a pad 31 is arranged on the upper end face of the substrate 3, the pad 31 on the substrate 3 is located in an annular metal layer of the substrate, the pad on the substrate 3 is electrically connected with the optical chip 5 through a gold wire bonding process, a first pad 22 is arranged on the lower end face of the PCBA2, and the first pad 22 on the PCBA2 is vertically corresponding to the pad on the substrate 3 and is welded with the pad; the first pad 22 is located in a second annular metal layer 25 of the lower end face of the PCBA 2.

The optical chip 5 is pasted on the insulating substrate 3 and is electrically connected with the bonding pad on the insulating substrate 3 by adopting a gold wire bonding process. In the present embodiment, a metal layer shaped like a Chinese character 'hui' is disposed on the upper end surface of the insulating substrate 3, and the optical chip 5 and the first bonding pad 22 are surrounded by the metal layer shaped like a Chinese character 'hui'. The metal layer in the shape of the Chinese character 'hui' of the insulating substrate 3 is connected with the gold-plated area of the copper foil on the back surface of the PCBA2 by adopting low-temperature metal solder to form the airtight package on the back surface. The through-holes 21 of the PCBA2 are also located in the "wrap-around" shaped metal layer of the insulating substrate 3.

The optical fiber array 1 substrate is provided with a metal layer shaped like a Chinese character 'hui', and the lens 6 is encircled in the metal layer shaped like a Chinese character 'hui'. The front surface of the PCBA2 is provided with a gold-plated area, and the square-shaped metal layer of the optical fiber array 1 substrate and the gold-plated area of the front surface of the PCBA2 are connected by adopting low-temperature metal solder to form the airtight package of the front surface. The through-holes 21 of the PCBA2 are also located in the "wrap-around" shaped metal layer of the substrate of the optical fiber array 1.

Further, a second pad 23 is arranged on the PCBA2, and the second pad 23 is electrically connected with the first pad 22 through an inner layer trace 26 of the PCBA 2.

The back surface of the PCBA2 is provided with first pads 22 (such as copper foil gold-plated pads) corresponding to the pads of the substrate 3, the first pads 22 on the back surface of the PCBA2 are connected with the pads on the substrate 3 by low-temperature metal solder, and the first pads 22 on the back surface of the PCBA2 are electrically connected with the second pads 23 on the back surface of the PCBA2 through punched (blind holes, without punching through the PCBA 2) wires 26. The second pads 23 are used to connect to corresponding circuitry on the PCBA, thereby enabling electrical communication between the optical chip and the PCBA.

Further, the second pad 23 is located in a region other than the annular metal layer.

Preferably, the insulating substrate is a ceramic substrate, but not limited to a ceramic substrate.

Further, the substrate of the optical fiber array 1 is provided with a reflecting surface 12, and the reflecting surface 12 is obliquely arranged and used for turning the optical path between the optical fiber and the optical chip 5 by 90 degrees. The substrate of the optical fiber array 1 of this embodiment is provided with an inclined surface, and a reflective layer (such as a gold plating layer) is provided on the inclined surface to form a reflective surface 12. The reflecting surface 12 is a total reflecting surface 12.

Example two

The embodiment of the utility model discloses optical module has adopted like embodiment one the packaging structure of optical module.

The utility model discloses an optical chip 5, lens 6 and optical chip 5 and the light path between the lens 6 are arranged in PCBA 2's through-hole 21, do not receive external liquid to disturb, realize the gas tightness encapsulation, make the utility model discloses an optical module can directly use in liquid, certainly, the utility model discloses an optical module is also not only limited to use in the liquid cooling environment.

The above description is only a preferred embodiment of the present invention, and should not be taken as limiting the invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An optical module packaging structure is characterized in that: including fiber array, PCBA and base plate, PCBA is equipped with the through-hole, fiber array and PCBA's one side fixed connection to cover PCBA's through-hole completely, base plate and PCBA's another side fixed connection to cover PCBA's through-hole completely, form airtight chamber between fiber array, PCBA, base plate, set up the optical chip on the base plate, the optical chip is located airtight intracavity.

2. The package for a light module according to claim 1, wherein: and the optical fiber array is fixedly connected with the PCBA in an airtight welding mode.

3. The optical module package structure according to claim 1, wherein: the optical fiber array is provided with lenses, the lenses are located in the airtight cavities, and the lenses are in one-to-one correspondence with the optical chips up and down.

4. A light module package according to claim 3, wherein: the lower terminal surface of fiber array substrate is equipped with annular metal layer, and lens are located the annular metal layer of fiber array substrate, PCBA's up end is equipped with first annular metal layer, and PCBA's through-hole is located first annular metal layer, and welded fastening forms airtight encapsulation between the annular metal layer of first annular metal layer of PCBA up end and fiber array substrate.

5. The optical module package structure according to claim 1, wherein: the base plate and the PCBA are fixedly connected in an airtight welding mode.

6. The optical module package according to claim 5, wherein: the base plate is insulating substrate, the up end of base plate is equipped with the annular metal layer, the optical chip is located the annular metal layer of base plate, PCBA's lower terminal surface is equipped with the second annular metal layer, and PCBA's through-hole is located the second annular metal layer, and welded fastening forms airtight encapsulation between the annular metal layer of the second annular metal layer of terminal surface and base plate up end under the PCBA.

7. The optical module package according to claim 6, wherein: a bonding pad is arranged on the upper end face of the substrate, the bonding pad on the substrate is positioned in the annular metal layer, the bonding pad on the substrate is electrically connected with the optical chip through gold wire bonding, a first bonding pad is arranged on the lower end face of the PCBA, and the first bonding pad on the PCBA is vertically corresponding to the bonding pad on the substrate and is welded with the bonding pad on the substrate; the first pad is located in the second annular metal layer of the PCBA lower end face.

8. The optical module package according to claim 7, wherein: the PCBA is provided with a second bonding pad, and the second bonding pad is electrically connected with the first bonding pad through inner-layer wiring of the PCBA.

9. The optical module package structure according to claim 1, wherein: the optical fiber array is provided with a reflecting surface, and the reflecting surface is obliquely arranged and used for turning the light path between the optical fiber and the optical chip by 90 degrees.

10. An optical module, characterized in that: a package structure using the optical module according to any one of claims 1 to 9.