Liquid-cooled optical module assembly and preparation method thereof, and electronic equipment

Abstract

The present invention relates to the field of optical module component protection technology, and discloses a liquid-cooled optical module component and a preparation method thereof, and an electronic device, wherein the liquid-cooled optical module component comprises a printed circuit board and a protective coating, wherein the protective coating is arranged on at least one side surface of the printed circuit board; wherein the protective coating has a three-dimensional network structure, and the composition of the protective coating comprises acrylate and metal nitride, wherein the metal nitride comprises at least one of aluminum oxynitride and zinc oxynitride. The protective coating in the liquid-cooled optical module component has high thermal conductivity, mechanical properties, and anti-corrosion properties, so it can effectively protect the printed circuit board, thereby helping to improve the performance of the liquid-cooled optical module component.

Description

Technical Field

[0001] The present invention relates to the technical field of optical module component protection, and in particular to a liquid-cooled optical module component and a preparation method thereof, and an electronic device. Background Art

[0002] As a carrier and connector of electronic components, printed circuit boards play an important role in the signal conversion of optical module components. In order to ensure the stable operation of optical module components, higher and higher requirements are placed on the packaging and protection performance of printed circuit boards.

[0003] There is a certain mutual restraint between the compactness, thermal conductivity and corrosion resistance of existing protective coatings, which are difficult to balance, thus limiting the performance of the protective coatings and making the printed circuit boards susceptible to corrosion and short circuit risks, thus affecting their performance and service life. Summary of the invention

[0004] The embodiment of the present invention discloses a liquid-cooled optical module assembly, a preparation method thereof, and an electronic device. The protective coating in the liquid-cooled optical module assembly has high thermal conductivity, mechanical properties, and corrosion resistance, so it can effectively protect the printed circuit board, thereby helping to improve the performance of the liquid-cooled optical module assembly.

[0005] In a first aspect, an embodiment of the present application discloses a liquid-cooled optical module assembly, the liquid-cooled optical module assembly comprising a printed circuit board and a protective coating, wherein the protective coating is disposed on at least one side surface of the printed circuit board;

[0006] The protective coating has a three-dimensional network structure, and the protective coating is composed of acrylate and metal nitride, and the metal nitride includes at least one of aluminum oxynitride and zinc oxynitride.

[0007] Furthermore, the three-dimensional network structure is formed by cross-linking part or all of the metal nitride and the acrylate.

[0008] Further, part of the metal nitride and part of the acrylate are cross-linked to form the three-dimensional network structure;

[0009] The metal oxynitride has pores, and another portion of the acrylate fills the pores of the metal oxynitride.

[0010] Further, the printed circuit board comprises a substrate and an optoelectronic chip disposed on the front side of the substrate;

[0011] The liquid-cooled optical module assembly also includes a lens, which is arranged on the front side of the substrate. The lens seals and covers the optoelectronic chip, and the protective coating covers the lens and the printed circuit board.

[0012] Furthermore, the liquid-cooled optical module assembly also includes an optical fiber connecting line, which is connected to the lens, and the protective coating is also provided on the connecting area between the optical fiber connecting line and the lens.

[0013] Furthermore, the outer surface of the optical fiber connecting line is wrapped with a protective sheath, and the material of the protective sheath includes one or more of polyether polyurethane elastomer, polytetramethylene furan polyurethane elastomer, polycaprolactone polyurethane elastomer, polyvinylidene fluoride, and polyimide elastomer; and / or,

[0014] The optical fiber connecting line is a branch connecting line with a brancher, the branch connecting line includes a main connecting line, a plurality of sub-connecting lines and an inner tube, the inner tube is provided with a receiving cavity extending along the length direction of the main connecting line, the main connecting line and the plurality of sub-connecting lines are connected in the receiving cavity, the receiving cavity is also filled with a sealing material, and the sealing material is configured to be filled in the receiving cavity by vapor deposition; and / or,

[0015] The optical fiber connecting line is connected to the lens via a first sealant, and the protective coating covers the first sealant, the lens, and the optical fiber connecting line in the connection area.

[0016] Furthermore, the liquid-cooled optical module assembly further comprises a housing, the housing comprising a first housing and a second housing, the first housing and the second housing are arranged opposite to each other to form a mounting cavity, and the printed circuit board is arranged in the mounting cavity;

[0017] The second shell is arranged opposite to the back side of the substrate, a heat-conducting pad is arranged on a surface of the second shell close to the substrate, and the protective coating covers the heat-conducting pad.

[0018] Further, the periphery of the lens is sealed by a first sealant and connected to the printed circuit board, a second sealant is provided on the lens, the second sealant is configured to connect the lens and the printed circuit board together, and the bonding force of the second sealant is greater than that of the first sealant; and / or,

[0019] The material of the lens includes one or more of polyetherimide, acrylic, single crystal silicon, polycrystalline silicon, BF33, quartz glass, and borosilicate glass.

[0020] Further, the printed circuit board comprises a substrate and an optoelectronic chip arranged on the substrate, wherein the substrate has a front side and a back side arranged opposite to each other;

[0021] Corresponding to the position of the optoelectronic chip, a heat dissipation structure is arranged between the back surface of the substrate and the protective coating.

[0022] Furthermore, the protective coating is provided on both side surfaces of the printed circuit board.

[0023] In a second aspect, an embodiment of the present application discloses a method for preparing the liquid-cooled optical module assembly described in the first aspect, the preparation method comprising the following steps:

[0024] The protective coating is prepared on at least one side of the printed circuit board by a vapor deposition method;

[0025] Wherein, the vapor deposition method comprises the following steps:

[0026] A precursor of metal nitride oxide and a precursor of the acrylate are introduced to deposit the protective coating on at least one side surface of the printed circuit board.

[0027] Furthermore, the acrylate precursor includes one or more of an acrylate monomer having two functional groups, an acrylate monomer having three functional groups, an epoxy-modified acrylate monomer and an organosilicon-modified acrylate.

[0028] Furthermore, the printed circuit board includes a substrate and an optoelectronic chip arranged on the substrate, and the substrate has a front side and a back side arranged opposite to each other;

[0029] Before the vapor deposition step, the preparation method further comprises:

[0030] Mounting a lens on the front surface of the substrate and sealingly covering the optoelectronic chip;

[0031] The lens and the optical fiber connecting line are connected together using a first sealant;

[0032] After the vapor deposition step, the preparation method further comprises: arranging the printed circuit board, the lens and the protective coating in a mounting cavity of a housing.

[0033] In a third aspect, an embodiment of the present application discloses an electronic device, comprising the liquid-cooled optical module assembly as described in any one of the first aspects.

[0034] Compared with the prior art, the beneficial effects of this application are:

[0035] The embodiment of the present application provides a liquid-cooled optical module assembly, which includes: a printed circuit board and a protective coating disposed on the front and back of the printed circuit board, the protective coating including: metal nitride oxide, acrylate, and since the metal nitride oxide includes at least one of aluminum oxynitride and zinc oxynitride, the presence of this component can improve the thermal conductivity of the material to a high degree, so that the prepared protective coating has good thermal conductivity. Among them, acrylate has good chemical resistance and water vapor resistance, and the metal nitride oxide can interact with acrylate, thereby further enhancing the chemical resistance and adhesion performance of the protective coating.

[0036] Specifically, since the protective coating has a three-dimensional network structure, the three-dimensional network structure forms a continuous heat conduction path in the protective coating, providing multiple heat transfer paths, which is helpful for heat transfer, and since the protective coating contains metal nitride, it helps to improve the thermal conductivity of the protective coating, so that heat has a higher conduction efficiency in the three-dimensional network structure, further improving the heat dissipation effect of the protective coating. In addition, the molecular cross-linking degree in the three-dimensional network structure is high and the connection stability is good, so it helps to reduce the pores and channels of the protective coating, improve the density and stability of the protective coating, and further inhibit the erosion of chemicals.

[0037] In addition, because acrylate has good thermal stability, when it is used as a component of the protective coating, it can effectively cope with the temperature changes of the printed circuit board, increase the thermal stability of the protective coating, and improve its protective effect. In addition, acrylate also has a high bonding effect and mechanical effect, which makes the protective coating fit tightly and adhere to the printed circuit board, and enables it to better disperse and withstand stress when subjected to external force, thereby improving its mechanical strength, helping to extend the service life of the protective coating, so that it can effectively play a protective role.

[0038] In summary, the protective coating provided in the present application includes metal nitride and acrylate, and because the protective coating has a three-dimensional network structure, the thermal conductivity, mechanical properties, and chemical protection properties of the protective coating are good, so that it can effectively protect the printed circuit board. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0040] Figure 1 is a schematic structural diagram of a liquid-cooled optical module assembly provided in an embodiment of the present application;

[0041] Figure 2 It is a cross-sectional schematic diagram of a liquid-cooled optical module assembly (housing and optical fiber connecting wires omitted) provided in an embodiment of the present application;

[0042] Figure 3 It is a cross-sectional schematic diagram of another liquid-cooled optical module assembly (excluding the housing and the optical fiber connecting line) provided in an embodiment of the present application;

[0043] Figure 4 The embodiment of this application provides Figure 1 A partial enlarged view of A in the middle (i.e., a schematic diagram of the structure of the optical fiber connecting line and the lens located in the connection area);

[0044] Figure 5 is a schematic diagram of the structure of the optical fiber connecting line provided in an embodiment of the present application;

[0045] Figure 6 is a schematic diagram of the structure of a lens provided in an embodiment of the present application;

[0046] Figure 7 It is a structural schematic diagram of the back side of a printed circuit board provided in an embodiment of the present application;

[0047] Figure 8 It is a structural schematic diagram of the back side of another printed circuit board provided in an embodiment of the present application.

[0048] Icons: 1. Printed circuit board; 11. Substrate; 12. Optoelectronic chip; 13. Heat dissipation structure; 14. Gold finger area; 2. Protective coating; 21. Front protective coating; 22. Back protective coating; 3. Lens; 31. Side panel; 4. Fiber optic connecting line; 41. Main connecting line; 42. Sub-connecting line; 43. Inner tube; 5. Connection area; 6. Shell; 61. First shell; 62. Second shell; 621. Thermal pad. DETAILED DESCRIPTION

[0049] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0050] In the present invention, the directions or positional relationships indicated by the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal" and the like are based on the directions or positional relationships shown in the drawings. These terms are mainly used to better describe the present invention and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific direction, or to be constructed and operated in a specific direction.

[0051] In addition, some of the above terms may be used to express other meanings in addition to indicating orientation or positional relationship. For example, the term "on" may also be used to express a certain dependency or connection relationship in some cases. For those skilled in the art, the specific meanings of these terms in the present invention can be understood according to specific circumstances.

[0052] In addition, the terms "first", "second", etc. are mainly used to distinguish different devices, elements or components (the specific types and structures may be the same or different), and are not used to indicate or imply the relative importance and quantity of the indicated devices, elements or components. Unless otherwise specified, "plurality" means two or more.

[0053] The technical solution provided by the present invention will be further described below in conjunction with embodiments and drawings.

[0054] At present, optical module components are widely used in data centers. Printed circuit boards, as carriers and connectors of electronic components, will generate a lot of heat during operation. Therefore, in order to effectively increase the rate of heat dissipation, the optical module components are immersed in coolant to speed up the heat exchange rate and improve the heat dissipation efficiency of the optical module components, thereby effectively ensuring the reliability of the optical module components.

[0055] However, since the coolant contains various types of chemicals, and these chemicals have a certain corrosive effect on the printed circuit board, it will affect the structural stability of the printed circuit board, resulting in obstruction of the operation of the optical module assembly. Therefore, in order to ensure the stable operation of the optical module assembly, higher and higher requirements are placed on the packaging and protection performance of the printed circuit board.

[0056] The protective coating of existing printed circuit boards is a polymer coating. Although the polymer coating has good anti-corrosion properties, its thermal conductivity is poor, which affects the heat dissipation effect, making it difficult to balance the density, thermal conductivity and anti-corrosion properties of the protective coating. The performance of the protective coating is limited and it is difficult to effectively play a protective and encapsulating role.

[0057] Based on the above problems, the embodiments of the present application provide a liquid-cooled optical module assembly, a preparation method thereof, and an electronic device, wherein the protective coating in the present application has high thermal conductivity, mechanical properties and anti-corrosion properties, so it can effectively protect the printed circuit board, thereby helping to improve the performance of the liquid-cooled optical module assembly.

[0058] The first aspect, such as Figures 1 to 3 As shown, an embodiment of the present application provides a liquid-cooled optical module assembly, the liquid-cooled optical module assembly includes a printed circuit board 1 and a protective coating 2, and the protective coating 2 is arranged on at least one side surface of the printed circuit board 1;

[0059] The protective coating 2 has a three-dimensional network structure. The protective coating 2 is composed of acrylate and metal nitride. The metal nitride includes at least one of aluminum oxynitride and zinc oxynitride.

[0060] In a first optional embodiment, the metal element includes zinc, so the metal nitride includes zinc oxynitride; in a second optional embodiment, the metal element includes aluminum, so the metal nitride includes aluminum oxynitride; in a third optional embodiment, the metal element includes zinc and aluminum, so the metal nitride includes zinc oxynitride and aluminum oxynitride. In this case, a three-dimensional network structure can be formed by cross-linking these two substances, and because aluminum is trivalent and zinc is divalent, there are more transmission paths and directions, which is more helpful to improve the heat dissipation effect, and the thermal conductivity of the two nitrides is different. Through the synergistic effect of the two, it is more helpful to improve the thermal conductivity of the protective coating 2.

[0061] It is understandable that the liquid-cooled optical module assembly of the present application refers to the use of coolant as a heat dissipation medium to remove the heat generated by the optical module assembly through heat exchange, thereby achieving the purpose of heat dissipation. Among them, the types of coolants include fluorinated liquid, silicone liquid or hydrocarbon oil; the types of fluorinated liquid include at least one of FC-40 and hexafluoropropylene trimer (Noah3000), the types of silicone liquid include ICL-1100, and the hydrocarbon oil includes at least one of polyalphaolefin (PAO 4), S3X, and DC15. When the above coolant is used, the protective coating 2 has better compatibility with the coolant, which is more conducive to improving the stability of heat dissipation.

[0062] Wherein, at least one side surface is provided with a protective coating 2, referring to Figure 2 , a protective coating 2 is provided on one side of the printed circuit board 1, that is, a protective coating 2 is provided on the front or back side of the printed circuit board 1. Alternatively, refer to Figure 3A protective coating 2 is provided on both sides of the printed circuit board 1, that is, a front protective coating 21 is prepared on the front of the printed circuit board 1, and a back protective coating 22 is prepared on the back. When the protective coating 2 is provided on both sides, the protective effect on the printed circuit board 1 is better, which is more helpful to improve the protective effect and improve the performance of the liquid-cooled optical module assembly.

[0063] The protective coating 2 disclosed in the embodiment of the present application includes metal nitride and acrylate, wherein the metal nitride includes at least one of zinc oxynitride and aluminum oxynitride, and the metal nitride can effectively improve the thermal conductivity of the protective coating 2. Moreover, the metal nitride and acrylate can cooperate with each other, thereby further improving the compactness and corrosion resistance of the protective coating 2.

[0064] Specifically, the three-dimensional network structure in the protective coating 2 can provide multiple heat transfer paths, and the continuity of the transfer paths is high, which can effectively improve the heat transfer efficiency. And because the protective coating 2 contains metal nitride, it helps to improve the thermal conductivity of the protective coating 2, thereby further increasing the heat transfer efficiency, and helping to improve the heat dissipation effect of the liquid-cooled optical module assembly. In addition, the molecules of the three-dimensional network structure have a high degree of cross-linking, higher density and good connection stability, which can effectively reduce defects such as pores and cracks in the protective coating 2, increase the density and structural stability of the protective coating 2, so that it can effectively avoid chemical erosion and improve its protection effect.

[0065] In addition, because acrylate has good thermal stability, when it is used as a component of the protective coating 2, it can effectively cope with the temperature changes of the printed circuit board 1, increase the thermal stability of the protective coating 2, and improve its protective effect. In addition, acrylate also has a high bonding effect and mechanical effect, so that the protective coating 2 and the printed circuit board 1 have a high degree of tightness and good adhesion, and enable it to better disperse and withstand stress when subjected to external force, thereby improving its mechanical strength, helping to extend the service life of the protective coating 2, so that it can effectively play a protective effect.

[0066] It should be noted that although the use of heat dissipation copper layer and injection molding hot melt parts can also achieve the protective effect on the printed circuit board 1, the thermal expansion coefficient of the heat dissipation copper layer is different from the thermal expansion coefficient of other materials in the printed circuit board 1, which leads to thermal stress when the temperature changes, resulting in poor tightness between the heat dissipation copper layer and the printed circuit board 1. In addition, the injection molding hot melt parts may age during long-term use, resulting in reduced sealing, thereby affecting the service life of the liquid-cooled optical module assembly. By setting the protective coating 2 of the present application on the printed circuit board 1, on the one hand, the acrylate in the protective coating 2 of the present application has low stress and high adhesion properties, so that the protective coating 2 and the printed circuit board 1 are more tightly fitted, which can effectively play a protective effect. On the other hand, the protective coating 2 of the present application has high stability, which can effectively cope with temperature changes and chemical reagent erosion. During long-term use, it still has a high protective effect, which helps to improve the service life of the liquid-cooled optical module assembly.

[0067] It can be understood that the three-dimensional network structure in the protective coating 2 includes at least one of a three-dimensional network structure formed by the metal nitride itself, a three-dimensional network structure formed by the acrylate itself, and a three-dimensional network structure formed by a mixture of the metal nitride and the acrylate.

[0068] The three-dimensional network structure is formed by partially or completely cross-linking metal nitride and acrylate.

[0069] Specifically, the active groups in the acrylate and the active groups in the metal nitride are chemically bonded together to form a three-dimensional network structure, and this method of chemical bonding makes the three-dimensional network structure more cross-linked, so the three-dimensional network structure has a higher density and good connection stability, which can effectively reduce defects such as pores and cracks in the protective coating 2, increase the density and structural stability of the protective coating 2, so that it can effectively avoid corrosion by chemicals and improve its protective effect.

[0070] In addition, since the metal nitride oxide is a component of the three-dimensional network structure, it can effectively improve the thermal conductivity of the three-dimensional network structure and effectively increase the heat dissipation rate of the three-dimensional network structure, thereby improving the thermal conductivity of the protective coating 2 to a high degree.

[0071] It can be understood that the three-dimensional network structure in the protective coating 2 of the present application is jointly formed by metal nitride and acrylate. Compared with the independent layer structure, the connection between the metal nitride and acrylate of the present application is more stable, and the degree of mutual influence is higher, which is more conducive to forming a highly stable, dense and thermally conductive protective coating 2, thereby further improving the service life and stability of the liquid-cooled optical module assembly.

[0072] Furthermore, the three-dimensional network structure can be formed by cross-linking part of the metal oxynitride and the acrylate, and the other part of the acrylate and the metal oxynitride are combined in other forms. For example, since the metal oxynitride has a porous structure, the other part of the acrylate is filled in the pores of the metal oxynitride, thereby further improving the compactness of the coating.

[0073] Therefore, when part of the metal nitride is bonded to the acrylate through chemical bonds, due to the saturation of the chemical bonds, part of the acrylate exists in a free state, and since the metal nitride contains pores, the acrylate in a free state will be filled in the pores of the metal nitride through van der Waals forces, electrostatic adsorption, physical adsorption, etc., thereby further increasing the density of the film layer of the protective coating 2, and further contributing to improving the corrosion resistance and density of the protective coating 2.

[0074] It can be understood that the pores of metal nitride include two parts. The first part refers to when part of the metal nitride exists in a three-dimensional network structure, which refers to the pores in the three-dimensional network structure. The second part refers to when part of the metal nitride exists in a free state, which refers to the pores in the free state.

[0075] In an optional embodiment, the protective coating 2 includes metal nitride and acrylate. In this case, the protective coating 2 includes 70% to 95% of the metal nitride and 5% to 30% of the acrylate by weight. When the content of the metal nitride and the acrylate is within the above range, the synergistic effect between the metal nitride and the acrylate is good, the stability of the formed three-dimensional network structure is good, and the protective coating 2 has high thermal conductivity and high chemical resistance.

[0076] In another optional embodiment, the protective coating 2 includes a metal oxynitride composition and an acrylate, the metal oxynitride composition includes a metal nitride oxide, and the protective coating 2 includes 70% to 95% of the metal oxynitride composition and 5% to 30% of the acrylate by weight. When the content of the metal oxynitride composition and the acrylate is within the above range, the synergistic effect between the metal oxynitride composition and the acrylate is good, the stability of the formed three-dimensional structure is good, and the protective coating 2 has high thermal conductivity and high chemical resistance.

[0077] In addition, the metal oxynitride composition also includes at least one element of B, Ti, Zr, and Si, so that the metal oxynitride composition also includes aluminum oxide, zinc oxide, boron nitride, zirconium oxide, titanium oxide and other substances. Among them, when the metal oxynitride composition includes at least one of aluminum oxide, zinc oxide and boron nitride, the thermal conductivity of the protective coating 2 can be further improved, so that it has a higher thermal conductivity; when the metal oxynitride composition includes zirconium oxide, the wear resistance of the protective coating 2 can be further optimized and its service life can be increased; when the metal oxynitride composition includes titanium oxide, it helps to improve the flexibility and adhesion of the protective coating 2, so that the protective coating 2 has a high degree of contact with the optical module component, and can play a high degree of sealing and protection effect.

[0078] Furthermore, the structural formula of the metal nitride is MNHxOy, wherein 0<x≤0.5, 1.5≤y≤2.0, and M is a metal element. When x and y satisfy the above relationship, the compactness of the formed protective coating 2 is better, which is more conducive to improving the thermal conductivity of the protective coating 2. Since the metal nitride also contains hydrogen, the chemical bonds in the metal nitride will include amino groups and hydroxyl groups. The above groups can react with acrylate to form covalent bonds, thereby generating a higher chemical bonding force, further improving the stability of the three-dimensional network skeleton.

[0079] Furthermore, the thickness of the protective coating 2 is 0.1 μm to 50 μm. When the thickness of the protective coating 2 is within the above range, it can effectively seal and protect, effectively block the corrosion of chemical reagents, and help transfer the heat in the liquid-cooled optical module assembly to the external environment, thereby helping to further improve the service life and stability of the optical module assembly.

[0080] For further information, see Figure 3 The printed circuit board 1 comprises: a substrate 11 having a front side and a back side arranged opposite to each other, and an optoelectronic chip 12 arranged on the front side of the substrate 11;

[0081] The liquid-cooled optical module assembly further includes a lens 3 , which is disposed on the front side of the substrate 11 . The lens 3 seals and covers the optoelectronic chip 12 , and the protective coating 2 covers the lens 3 and the printed circuit board 1 .

[0082] In an optional embodiment, the volume of the accommodating cavity of the lens 3 that seals and covers the optoelectronic chip 12 is close to the volume of the optoelectronic chip 12; in another optional embodiment, the volume of the accommodating cavity of the lens 3 is larger than the volume of the optoelectronic chip 12, which is more helpful to reduce the friction between the lens 3 and the optoelectronic chip 12 and improve the service life of the optoelectronic chip 12.

[0083] The optoelectronic chip 12 is the main structural unit for converting and processing optoelectronic signals. The present application adopts a lens 3 to seal and cover the optoelectronic chip 12, thereby forming a first layer of sealing protection design, and further covers the lens 3 and the printed circuit board 1 with a protective coating 2, thereby forming a second layer of sealing protection design, which effectively protects the optoelectronic chip 12, thereby ensuring the performance of the optoelectronic chip 12 and improving its stability in use.

[0084] The material of the lens 3 includes one or more of polyetherimide, acrylic, single crystal silicon, polycrystalline silicon, quartz glass, and borosilicate glass (such as model BF33).

[0085] And, if Figure 4 As shown, the liquid-cooled optical module assembly also includes an optical fiber connecting line 4, which is connected to the lens 3, and a protective coating 2 is also provided on the connection area 5 between the optical fiber connecting line 4 and the lens 3. Since the optical fiber connecting line 4 is also immersed in the coolant when the liquid-cooled optical module assembly is immersed in the coolant, the protective coating 2 is provided to protect the connection area 5, improve the connection stability between the optical fiber connecting line 4 and the lens 3, and ensure the effective transmission of the signal.

[0086] Optionally, the optical fiber connecting line 4 is connected to the lens 3 through a first sealant, and the protective coating 2 covers the first sealant, the lens 3 and the optical fiber connecting line 4 in the connection area 5. Since the protective coating 2 covers the first sealant, the effectiveness of the first sealant connection is guaranteed, so that the connection stability between the optical fiber connecting line 4 and the first sealant is high. Among them, the first sealant includes a UV curing agent.

[0087] The main function of the optical fiber connection line 4 is to transmit optical signals. The optical fiber connection line 4 includes optical fiber jumpers, optical fiber pigtails, optical cables, etc.

[0088] It can be understood that the lens 3 is used to couple the optical signal emitted by the optoelectronic chip 12 and transmit it to the optical fiber connecting line 4, or to receive the optical signal transmitted by the optical fiber connecting line 4 and couple it to the optoelectronic chip 12. That is to say, during the operation of the entire liquid-cooled optical module assembly, the stability of the connection between the optical fiber connecting line 4 and the lens 3 affects the efficiency and stability of the optical signal transmission. The use of the setting of the present application can not only increase the protection of the optoelectronic chip 12 and improve the operating stability and effectiveness of the optoelectronic chip 12, but also ensure the stability of the connection between the optical fiber connecting line 4 and the lens 3, thereby helping to ensure the operating performance of the liquid-cooled optical module assembly and improve its service life.

[0089] Furthermore, the outer surface of the optical fiber connecting line 4 is wrapped with a protective cover, and the material of the protective cover includes one or more of polyether polyurethane elastomer, polytetramethylene urethane elastomer, polycaprolactone polyurethane elastomer, polyvinylidene fluoride, and polyimide elastomer. When the material of the protective cover is of the above type, the material has better compatibility with the coolant, which is more helpful to improve the reliability of the liquid-cooled optical module assembly.

[0090] Furthermore, if Figure 5 As shown, the optical fiber connection line 4 is a branch connection line with a branching device, and the branch connection line includes a main connection line 41, a plurality of sub-connection lines 42 and an inner tube 43. The inner tube 43 is provided with a plurality of sub-connection lines 42 along the length direction of the main connection line 41 (see Figure 5 The main connection line 41 and the plurality of sub-connection lines 42 are connected in the accommodating cavity, and the accommodating cavity is also filled with a sealing material, which is configured to be filled in the accommodating cavity by vapor deposition. Since the sealing material in the accommodating cavity is deposited by vapor deposition, the tightness of the seal is ensured, and the stability of use is improved.

[0091] For further information, see Figure 1 The liquid-cooled optical module assembly further includes a housing 6, the housing 6 includes a first housing 61 and a second housing 62, the first housing 61 and the second housing 62 are arranged opposite to each other to form a mounting cavity, and the printed circuit board 1 is arranged in the mounting cavity;

[0092] The second shell 62 is disposed opposite to the back surface of the substrate 11 , a heat-conducting pad 621 is disposed on a surface of the second shell 62 close to the substrate 11 , and the protective coating 2 covers the heat-conducting pad 621 .

[0093] The provision of the thermal pad 621 of the present application enables a better heat dissipation effect of the printed circuit board 1, and by further providing a protective coating 2 on the thermal pad 621, the thermal pad 621 is highly compatible with the coolant, thereby ensuring the stability of heat transfer and improving the heat dissipation effect.

[0094] Furthermore, the periphery of the lens 3 is sealed by a first sealant and connected to the printed circuit board 1, and a second sealant is provided on the lens 3, and the second sealant is configured to connect the lens 3 and the printed circuit board 1 together, and the bonding force of the second sealant is greater than that of the first sealant.

[0095] The periphery of the lens 3 refers to the boundary area of ​​the outline of the lens 3. For example, the lens is a rectangular parallelepiped structure. Figure 6 As shown, the lens 3 is a rectangular parallelepiped structure with an accommodating cavity, and the periphery refers to four side panels 31 of the rectangular parallelepiped structure in contact with the printed circuit board 1 .

[0096] In the present application, the lens 3 is pre-fixed on the printed circuit board 1 by using a first sealant, and the lens 3 and the printed circuit board 1 are further fixed together by using a second sealant, and since the bonding force of the second sealant is greater than that of the first sealant, the tightness and stability of the connection are ensured. In addition, the first sealant includes ultraviolet light curing glue, and the second sealant includes black glue.

[0097] In an optional embodiment, if Figure 7 As shown, the printed circuit board 1 includes a substrate 11 and an optoelectronic chip 12 disposed on the substrate 11, and the substrate 11 has a front side and a back side disposed opposite to each other;

[0098] Corresponding to the position of the optoelectronic chip 12 , a heat dissipation structure 13 is disposed between the back side of the substrate 11 and the protective coating 2 .

[0099] In another optional embodiment, if Figure 8 As shown, a heat dissipation structure 13 is provided between the back side of the substrate 11 and the protective coating 2 corresponding to the position of the optoelectronic chip 12 .

[0100] By arranging a heat dissipation structure 13 at a position corresponding to the optoelectronic chip 12 on the back side of the substrate 11, the effectiveness of heat dissipation of the optoelectronic chip 12 is further improved. In addition, since a protective coating 2 is provided on the heat dissipation structure 13, its compatibility with the coolant is higher, thereby improving the heat dissipation effect.

[0101] The heat dissipation structure 13 includes heat dissipation gel or heat dissipation pad.

[0102] In a second aspect, an embodiment of the present application discloses a method for preparing the liquid-cooled optical module assembly of the first aspect, the preparation method comprising the following steps:

[0103] A protective coating is prepared on at least one side of a printed circuit board by using a vapor deposition method.

[0104] When the chemical vapor deposition process is used to prepare the protective coating, the process conditions are controllable, the prepared film layer has high density and good uniformity, which can effectively improve the protective performance of the protective coating and make the coating and the optical module component more tightly bonded, thereby helping to improve the service life and stability of the optical module component.

[0105] Further, the method of vapor deposition comprises the following steps:

[0106] A metal nitride oxide precursor and an acrylate precursor are introduced to deposit a protective coating on at least one side of the printed circuit board.

[0107] Since the two substances are mixed in the form of gas, the two substances are more evenly distributed in the prepared protective coating, which is more conducive to improving the sufficiency of the reaction and the protective performance of the protective coating.

[0108] Among them, the precursor of the metal nitride oxide composition includes a material source and a gas source. The material source includes at least one of methyl zinc, ethyl zinc, ethyl aluminum, ethoxide zinc, tetraethyl zirconate, isopropoxide aluminum, tetraethyl titanate, butyl boron, ethoxide zirconium, ethoxide tantalum, and triethoxyphosphorus; the gas source includes at least one of nitrogen and ammonia.

[0109] Furthermore, the gas source also includes tetrafluoroethylene. When the gas contains tetrafluoroethylene, the protective coating contains fluorine element, which can further improve the hydrophobic and oleophobic properties of the protective coating and improve the protective effect of the protective coating.

[0110] It is understandable that the gas source can be introduced at the same time as the material source; the gas source can also be introduced before the material source, so as to ensure that when the material source is introduced later, it can directly react with the material source; the present application does not limit the order of introduction of the gas source and the material source, as long as it can ensure that the gas source and the material source can fully react.

[0111] The precursor of the acrylate includes one or more of an acrylate monomer having two functional groups, an acrylate monomer having three functional groups, an epoxy-modified acrylate monomer, and an organosilicon-modified acrylate. Specifically, the precursor of the acrylate includes at least one of glycidyl methacrylate, pentaerythritol tetraacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, tripropylene glycol diacrylate, ethylene glycol dimethacrylate, and γ-methacryloxypropyltrimethoxysilane.

[0112] Furthermore, the printed circuit board includes a substrate and an optoelectronic chip disposed on the substrate, wherein the substrate has a front side and a back side disposed opposite to each other;

[0113] See back Figure 1 The printed circuit board also includes a gold finger area 14 , which is connected to the substrate 11 . Before the vapor deposition step, the preparation method further includes: shielding the gold finger area 14 .

[0114] The gold finger area 14 is the portion where the printed circuit board is electrically connected to other structures. Before depositing the protective coating, it needs to be shielded to avoid the protective coating being deposited on the area, thereby ensuring the stability of the electrical connection.

[0115] Furthermore, before the step of shielding the gold finger area, the preparation method further comprises:

[0116] Mounting the lens on the front side of the substrate and sealing and covering the optoelectronic chip;

[0117] The lens and the optical fiber connecting line are connected together using a first sealant;

[0118] After the vapor deposition step, the preparation method further comprises: placing the printed circuit board, the lens and the protective coating in the installation cavity of the housing.

[0119] In a third aspect, an embodiment of the present application discloses an electronic device, which includes the liquid-cooled optical module assembly of the first aspect.

[0120] The technical solution of the present application will be further explained below in conjunction with more specific embodiments and experimental test results.

[0121] Embodiment 1:

[0122] The present invention provides a liquid-cooled optical module assembly, and the preparation method thereof comprises the following steps:

[0123] Provided is a printed circuit board, wherein a photoelectric chip is arranged on the front side of a substrate of the printed circuit board, and a heat dissipation structure is arranged on the back side of the substrate corresponding to the position of the photoelectric chip;

[0124] Pre-bonding the periphery of the lens to the front side of the substrate by means of UV curing adhesive, further connecting the lens to the front side of the substrate by means of black glue, and making the lens seal the optoelectronic chip on the printed circuit board;

[0125] The lens and the optical fiber jumper are connected together by using ultraviolet curing glue, and the optical fiber jumper is a branch connection line with a brancher, and the material of the protective cover of the optical fiber jumper is polytetramethylene urethane elastomer;

[0126] After the gold finger area is shielded, the printed circuit board is placed in a vapor deposition furnace, and a precursor of a metal nitride oxide composition and a precursor of an acrylate are introduced, and a 20 μm thick protective coating is deposited on the surfaces of both sides of the printed circuit board, on the connection area between the lens and the optical fiber jumper, and on the heat dissipation structure by a chemical vapor deposition process, wherein the material source of the metal nitride oxide composition includes ethyl aluminum and ethyl zinc, the gas source is nitrogen, and the precursor of the acrylate includes pentaerythritol triacrylate; the flow rate ratio of ethyl aluminum, ethyl zinc and pentaerythritol triacrylate is set to 3:3:1, respectively, the coating pressure is 0.01 atm, the process time is 12 hours, the mass content of the metal nitride oxide composition is 85%, the mass content of the acrylate is 15%, and the temperature of the coating chamber is 50°C;

[0127] The printed circuit board, the lens and the protective coating are all arranged in the installation cavity formed by the first shell and the second shell, and a heat-conducting pad is arranged on the surface of one side of the second shell close to the substrate, and the protective coating is arranged on the heat-conducting pad.

[0128] Embodiment 2:

[0129] The difference between this embodiment and embodiment 1 is that the gas source is a mixture of nitrogen and tetrafluoroethylene, and the flow rate ratio of nitrogen to tetrafluoroethylene is 1:1.

[0130] Embodiment 3:

[0131] The difference between this embodiment and embodiment 1 is that the precursor of acrylate includes pentaerythritol triacrylate and glycidyl methacrylate, and the flow rate ratios of ethyl aluminum, ethyl zinc, pentaerythritol triacrylate and glycidyl methacrylate are 3:5:0.6:0.4 respectively.

[0132] Embodiment 4:

[0133] The difference between this embodiment and embodiment 1 is that the process time is 3 hours.

[0134] Embodiment 5:

[0135] The difference between this embodiment and embodiment 1 is that the temperature of the coating chamber is 60°C.

[0136] Embodiment 6:

[0137] The difference between this embodiment and embodiment 1 is that the material source of the metal nitride oxide composition includes ethyl aluminum, zinc ethoxide, and n-butyl titanate, the precursor of the acrylate includes pentaerythritol triacrylate and glycidyl methacrylate, and the flow rate ratios of ethyl aluminum, zinc ethoxide, n-butyl titanate, pentaerythritol triacrylate, and glycidyl methacrylate are 5:3:1:1:1, respectively.

[0138] Embodiment 7:

[0139] The difference between this embodiment and embodiment 1 is that the material source of the metal nitride oxide composition includes ethyl aluminum, zinc ethoxide, and n-butyl titanate, the precursor of the acrylate includes pentaerythritol triacrylate and glycidyl methacrylate, and the flow rate ratios of ethyl aluminum, zinc ethoxide, n-butyl titanate, pentaerythritol triacrylate, and glycidyl methacrylate are 3:5:1:1:1, respectively.

[0140] Embodiment 8:

[0141] The difference between this embodiment and embodiment 1 is that the gas source is a mixture of nitrogen and tetrafluoroethylene, the flow rate ratio of nitrogen to tetrafluoroethylene is 1:1, the material source of the metal nitride composition includes ethyl aluminum, zinc ethoxide, and n-butyl titanate, the precursor of the acrylate includes pentaerythritol triacrylate and glycidyl methacrylate, and the flow rate ratios of ethyl aluminum, zinc ethoxide, n-butyl titanate, pentaerythritol triacrylate, and glycidyl methacrylate are 3:5:1:1:1, respectively.

[0142] Embodiment 9:

[0143] The difference between this embodiment and Embodiment 1 is that the material source of the metal nitride oxide composition includes ethyl aluminum, zinc ethoxide, and n-butyl titanate, the precursor of the acrylate includes tripropylene glycol diacrylate and glycidyl methacrylate, and the flow rate ratios of ethyl aluminum, zinc ethoxide, n-butyl titanate, tripropylene glycol diacrylate, and glycidyl methacrylate are 3:5:1:1:1, respectively.

[0144] Embodiment 10:

[0145] The difference between this embodiment and embodiment 1 is that the gas source introduced is a mixture of nitrogen and tetrafluoroethylene, the flow rate ratio of nitrogen to tetrafluoroethylene is 1:1, the material source of the metal nitride composition includes ethyl aluminum, zinc ethoxide, and n-butyl titanate, the precursor of the acrylate includes pentaerythritol triacrylate and glycidyl methacrylate, and the flow rate ratio of ethyl aluminum, zinc ethoxide, n-butyl titanate, pentaerythritol triacrylate, and glycidyl methacrylate are 6:2:1:1:1, respectively.

[0146] Embodiment 11:

[0147] The difference between this embodiment and embodiment 1 is that the coating time is 24 h, and no thermal conductive pad is provided on the second shell.

[0148] Embodiment 12:

[0149] The difference between this embodiment and embodiment 1 is that the coating time is 24 h, and no heat dissipation structure is provided on the substrate.

[0150] Comparative Example 1:

[0151] The only difference between this comparative example and Example 1 is that the prepared protective coating contains only a metal nitride oxide composition, and the material source of the metal nitride oxide composition includes tetraethyl orthosilicate and aluminum isopropoxide, and the flow rate ratio of tetraethyl orthosilicate to aluminum isopropoxide is 5:1.

[0152] Comparative Example 2:

[0153] The only difference between this comparative example and Example 1 is that the prepared protective coating contains only acrylate, the process time is 6 hours, the precursor of acrylate includes pentaerythritol triacrylate and glycidyl methacrylate, and the flow rate ratio of pentaerythritol triacrylate to glycidyl methacrylate is 1:1.

[0154] Comparative Example 3:

[0155] The difference between this comparative example and Example 1 is that the acrylate and the metal nitride oxide composition in the prepared protective coating are separate coatings, that is, in the step of preparing the protective coating, a layer of the metal nitride oxide composition is deposited first, and then a layer of the acrylate is deposited.

[0156] Test results:

[0157] In order to further verify the protective coating effects of the embodiments and comparative examples of the present application, the present application tests the performance of the protective coating.

[0158] Optoelectronic chip surface temperature: Use a thermometer to test the surface temperature of the optical module component.

[0159] High and low temperature cycle performance: In an environment of -40℃~100℃, the samples of the embodiments and comparative examples were cycled 100, 500 and 1000 times to test the stability of their performance, wherein the temperature change rate was ≥10℃ / min (temperature switching time 12.5 min), the high and low temperature holding time was greater than 10 min, and each cycle time was more than 45 minutes.

[0160] High temperature and high humidity performance: The samples of the embodiment and the comparative example were stored in an environment with a temperature of 85° C. and a humidity of 85% RH for 168 h, 500 h, and 1000 h, respectively.

[0161] Chemical resistance: Place the test sample in chemicals, heat the chemicals to 85°C, and soak for 2000 hours.

[0162] Boiling experiment: The samples of the embodiment and comparative example were boiled in boiling water at 100°C for 6h, 12h and 24h respectively.

[0163] Table 1 Performance of protective coatings in examples and comparative examples

[0164]

[0165] Note: “√” indicates that the performance of the liquid-cooled optical module component is better, and “╳” indicates that the performance of the liquid-cooled optical module component is worse.

[0166] Analysis of the data of Examples 1 to 9 and Comparative Example 1 shows that the performance of the examples is better than that of Comparative Example 1. This is because the protective coating of the examples includes a metal nitride oxide composition and acrylate, while Comparative Example 1 only contains a metal nitride oxide composition. Therefore, the three-dimensional network structure in the mixture of the examples, and the basic network skeleton of the three-dimensional network structure is metal nitride oxide, so it provides more heat conduction paths and improves the efficiency of heat conduction, thereby effectively increasing the thermal conductivity of the protective coating of the examples. In addition, the three-dimensional structure of the examples is composed of a metal nitride oxide composition and acrylate, so through cross-linking between chemical bonds, the prepared film layer has good density, which is more conducive to improving chemical resistance.

[0167] Analysis of the data of Examples 1 to 9 and Comparative Example 2 shows that the performance of the examples is better than that of Comparative Example 2. This is because the protective coating of the examples includes a metal nitride oxide composition and acrylate, while Comparative Example 2 contains only acrylate. Therefore, the metal nitride oxide composition in the examples can effectively improve the thermal conductivity of the protective coating, and the three-dimensional network structure in the mixture can conduct heat well, thereby facilitating the heat dissipation of the protective coating. The three-dimensional network structure makes the protective coating highly dense, which is more helpful in avoiding corrosion by chemicals.

[0168] Analysis of the data of Examples 1 to 9 and Comparative Example 3 shows that the surface temperature and chemical resistance of the examples are better than those of Comparative Example 3. This is because the metal nitride oxide composition and the acrylate in the examples are in the same layer structure, while the metal nitride oxide composition layer and the acrylate layer in Comparative Example 3 belong to separate layer structures. Therefore, the three-dimensional network structure composed of the metal nitride oxide composition and the acrylate has a high degree of cross-linking between molecules and a higher structural density. In addition, the basic network skeleton of the three-dimensional network structure is metal nitride oxide, which makes the heat dissipation rate faster, and is more conducive to improving the thermal conductivity and chemical resistance of the protective coating.

[0169] The above is a detailed introduction to the liquid-cooled optical module assembly, its preparation method, and the electronic device disclosed in the embodiments of the present application. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the liquid-cooled optical module assembly, its preparation method, and the electronic device: At the same time, for general technicians in this field, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A liquid-cooled optical module assembly, characterized in that: The liquid-cooled optical module assembly comprises a printed circuit board and a protective coating, wherein the protective coating is arranged on at least one side surface of the printed circuit board; The protective coating has a three-dimensional network structure, the protective coating comprises acrylate and metal nitride, the metal nitride comprises at least one of aluminum oxynitride and zinc oxynitride, and the three-dimensional network structure is formed by cross-linking part or all of the metal nitride and the acrylate.

2. The liquid-cooled optical module assembly according to claim 1, characterized in that: A portion of the metal nitride and a portion of the acrylate are cross-linked to form the three-dimensional network structure; The metal oxynitride has pores, and another portion of the acrylate fills the pores of the metal oxynitride.

3. The liquid-cooled optical module assembly according to claim 1, characterized in that: The printed circuit board comprises a substrate and an optoelectronic chip arranged on the front side of the substrate; The liquid-cooled optical module assembly also includes a lens, which is arranged on the front side of the substrate. The lens seals and covers the optoelectronic chip, and the protective coating covers the lens and the printed circuit board.

4. The liquid-cooled optical module assembly according to claim 3, characterized in that: The liquid-cooled optical module assembly also includes an optical fiber connecting line, which is connected to the lens, and the protective coating is also provided on the connecting area between the optical fiber connecting line and the lens.

5. The liquid-cooled optical module assembly according to claim 4, characterized in that: The outer surface of the optical fiber connecting line is wrapped with a protective sheath, and the material of the protective sheath includes one or more of polyether polyurethane elastomer, polytetramethylene furan polyurethane elastomer, polycaprolactone polyurethane elastomer, polyvinylidene fluoride, and polyimide elastomer; and / or, The optical fiber connecting line is a branch connecting line with a brancher, the branch connecting line includes a main connecting line, a plurality of sub-connecting lines and an inner tube, the inner tube is provided with a receiving cavity extending along the length direction of the main connecting line, the main connecting line and the plurality of sub-connecting lines are connected in the receiving cavity, the receiving cavity is also filled with a sealing material, and the sealing material is configured to be filled in the receiving cavity by vapor deposition; and / or, The optical fiber connecting line is connected to the lens via a first sealant, and the protective coating covers the first sealant, the lens, and the optical fiber connecting line in the connection area.

6. The liquid-cooled optical module assembly according to claim 3, characterized in that: The liquid-cooled optical module assembly further includes a housing, the housing including a first housing and a second housing, the first housing and the second housing being arranged opposite to each other to form a mounting cavity, the printed circuit board being arranged in the mounting cavity; The second shell is arranged opposite to the back side of the substrate, a heat-conducting pad is arranged on a surface of the second shell close to the substrate, and the protective coating covers the heat-conducting pad.

7. The liquid-cooled optical module assembly according to claim 3, characterized in that: The periphery of the lens is sealed by a first sealant and connected to the printed circuit board, a second sealant is provided on the lens, the second sealant is configured to connect the lens and the printed circuit board together, and the bonding force of the second sealant is greater than that of the first sealant; and / or, The material of the lens includes one or more of polyetherimide, acrylic, single crystal silicon, polycrystalline silicon, BF33, quartz glass, and borosilicate glass.

8. The liquid-cooled optical module assembly according to claim 1, characterized in that: The printed circuit board comprises a substrate and an optoelectronic chip arranged on the substrate, wherein the substrate has a front side and a back side arranged opposite to each other; Corresponding to the position of the optoelectronic chip, a heat dissipation structure is arranged between the back surface of the substrate and the protective coating.

9. The liquid-cooled optical module assembly according to claim 1, characterized in that: The protective coating is provided on both side surfaces of the printed circuit board.

10. A method for preparing a liquid-cooled optical module assembly according to any one of claims 1 to 9, characterized in that: The preparation method comprises the following steps: The protective coating is prepared on at least one side of the printed circuit board by a vapor deposition method; Wherein, the vapor deposition method comprises the following steps: A precursor of metal nitride oxide and a precursor of the acrylate are introduced to deposit the protective coating on at least one side surface of the printed circuit board.

11. The preparation method according to claim 10, characterized in that: The acrylate precursor includes one or more of an acrylate monomer having two functional groups, an acrylate monomer having three functional groups, an epoxy-modified acrylate monomer and an organosilicon-modified acrylate.

12. The preparation method according to claim 10, characterized in that: The printed circuit board comprises a substrate and an optoelectronic chip arranged on the substrate, wherein the substrate has a front side and a back side arranged opposite to each other; Before the vapor deposition step, the preparation method further comprises: Mounting a lens on the front surface of the substrate and sealingly covering the optoelectronic chip; The lens and the optical fiber connecting line are connected together using a first sealant; After the vapor deposition step, the preparation method further comprises: arranging the printed circuit board, the lens and the protective coating in a mounting cavity of a housing.

13. An electronic device, characterized in that: The electronic device comprises the liquid-cooled optical module assembly according to any one of claims 1 to 9.

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