Honeycomb diamond optical module shielding case and preparation method thereof

Abstract

The invention provides a honeycomb diamond optical module shielding case and a preparation method thereof. The shielding case comprises a double-layer structure. The upper layer of the double-layer structure is a metal sheet; the lower layer of the double-layer structure is honeycomb-shaped diamond; the metal sheet and the honeycomb-shaped diamond are connected by utilizing a nano-silver low-temperature sintering process; the honeycomb-shaped diamond comprises a plurality of honeycomb units which are connected with one another; and ventilation channels are formed among the honeycomb units. According to the invention, the influence of electromagnetic radiation and electromagnetic signals reaching the chip on the chip can be greatly reduced, and the heat dissipation capability is improved. A plurality of small honeycomb units are arranged in the honeycomb diamond layer structure, ventilation channels are formed among the small units, free flowing of air is facilitated, and when the material is heated, the air flows in the channels to take away heat on the surface of the material.

Description

Technical Field

[0001] The invention relates to the field of electronic components, and in particular to a honeycomb diamond optical module shielding cover and a preparation method thereof. Background Art

[0002] The optical module shielding cover is a tool located on the PCB board to shield electronic signals. It can shield the influence of external electromagnetic waves on the internal circuit and the electromagnetic waves generated internally from radiating outward, thus protecting the chip. At present, most metals are used as shielding covers in optical modules on the market because they can absorb or reflect electromagnetic waves. They can not only shield radio waves and electromagnetic wave signals, but also resist chemical corrosion and mechanical forces. Since the chip generates heat when working and there is an air gap between the chip and the shielding cover, the resulting temperature step will cause thermal resistance. The shielding cover has two layers of structure, namely: the upper layer of nickel silver and the lower layer of honeycomb diamond. Its advantage is that it has good stability, and the electromagnetic shielding performance of the composite material using honeycomb sandwich is greatly improved compared with the electromagnetic shielding performance of the general structure, which improves the electromagnetic shielding effect and heat dissipation performance of the shielding cover, thereby protecting the internal chip and improving the performance and service life of the chip.

[0003] However, the existing shielding covers still have the following problems: 1. Heat dissipation performance and electromagnetic shielding performance cannot be combined.

[0004] 2. Thermal resistance will affect the shape of the shield during heat transfer, causing damage to the chip.

[0005] In summary, it is necessary to design a shielding cover that can combine electromagnetic shielding effect and heat dissipation effect and is not easily deformed under high temperature conditions. Summary of the invention

[0006] In order to overcome the deficiencies of the prior art, the purpose of the present invention is to provide a honeycomb diamond optical module shielding cover and a preparation method thereof, which can improve the electromagnetic shielding performance and heat dissipation effect of the optical module shielding cover and improve the stability of the shielding cover when working at high temperatures.

[0007] To achieve the above object, the present invention provides the following solutions: A honeycomb diamond optical module shielding cover comprises: a double-layer structure; The upper layer of the double-layer structure is a metal sheet; the lower layer of the double-layer structure is a honeycomb diamond; the metal sheet and the honeycomb diamond are connected by using a nano-silver low-temperature sintering process; the honeycomb diamond includes a plurality of honeycomb units connected to each other; and ventilation channels are formed between the honeycomb units.

[0008] Preferably, the honeycomb diamond is a hollow rectangular parallelepiped structure; wherein the front, top and rear surfaces of the rectangular parallelepiped structure are all rectangles of 3mm×5mm, and the left and right surfaces of the rectangular parallelepiped structure are both squares of 3mm×3mm.

[0009] Preferably, the material of the metal sheet is nickel silver.

[0010] Preferably, the thickness of the metal sheet is 600 μm, and the thickness of the honeycomb diamond is 400 μm.

[0011] Preferably, the honeycomb diamond is made of diamond.

[0012] Preferably, the diamond is grown in a laboratory by chemical vapor deposition.

[0013] Preferably, the honeycomb diamond is obtained by laser cutting a honeycomb core shape on the diamond surface and then grinding and polishing it.

[0014] Preferably, the surface roughness of the honeycomb diamond after grinding and polishing is less than 10 nm.

[0015] A method for preparing a honeycomb diamond optical module shielding cover, comprising: The obtained metal sheet is used as the upper layer, the obtained honeycomb diamond is used as the lower layer, and the upper layer and the lower layer are connected by using a nano-silver low-temperature sintering process to obtain a double-layer structure.

[0016] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects: The present invention provides a honeycomb diamond optical module shielding cover and a preparation method thereof, which can greatly reduce the impact of electromagnetic radiation and electromagnetic signals reaching the chip on the chip and improve the heat dissipation capacity. There are many small honeycomb units inside the honeycomb diamond layer structure, and ventilation channels are formed between these small units, which are conducive to the free flow of air. When the material is heated, the air flows in these channels and takes away the heat from the surface of the material. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. 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 paying creative labor.

[0018] Figure 1 A schematic diagram of the overall structure provided by an embodiment of the present invention; Figure 2A schematic diagram of a double-layer structure provided by an embodiment of the present invention; Figure 3 A schematic diagram of a honeycomb diamond structure provided by an embodiment of the present invention; Figure 4 A schematic diagram of heat and electromagnetic wave transfer provided by an embodiment of the present invention.

[0019] Description of reference numerals: 1-honeycomb diamond optical module shielding cover; 2-chip; 3-PCB board; 4-nickel nickel silver, 5-honeycomb diamond. DETAILED DESCRIPTION

[0020] 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.

[0021] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] like Figure 1 As shown, the honeycomb diamond optical module shielding cover 1 provided by the present invention is specifically located on the PCB board 3 inside the optical module, and is specifically used to protect the optical module chip 2 and provide a stable working environment for the optical module chip 2. Exemplarily, the shielding cover is installed above the chip 2 of the PCB board 3.

[0023] like Figure 2As shown, the diamond honeycomb optical module shield provided by the present invention comprises a double-layer structure of an upper panel and a honeycomb core layer, wherein the diamond is obtained by a laboratory DC arc plasma jet CVD method, and the surface roughness is less than 10nm after grinding and polishing. The diamond is cut into a thin layer with a thickness of 400μm, and a honeycomb core shape with a side length of 100μm is laser cut on its surface to form a honeycomb core layer diamond. The two are connected by a nano-silver low-temperature sintering process. In the nano-silver low-temperature sintering process, the nano-silver grains are easily combined with each other, so that the grains grow, the grain boundaries are reduced, and a good heat conduction path is formed, thereby dissipating heat and achieving the purpose of protecting the chip 2. Among them, the nickel silver 4 can absorb and reflect electromagnetic waves, and the interference of electromagnetic waves and electromagnetic signals to the shielding chip 2 when it is working. The honeycomb diamond 5 can improve the heat dissipation efficiency of the chip 2. The honeycomb shape can not only increase the air circulation area, but also form a hollow structure to allow air to flow freely, thereby reducing the temperature inside the chip 2. Secondly, diamond has good thermal conductivity, and the thermal expansion coefficient of diamond and nickel silver 4 is not much different, so working in a high temperature environment will not affect the performance of the shielding cover, ensuring a stable working environment for the chip 2. The upper panel material is nickel silver 4 for shielding electromagnetic signals and electromagnetic radiation, and the honeycomb structure material is diamond for heat dissipation for the chip 2.

[0024] Furthermore, the thickness of nickel silver 4 is 600 μm, and the thickness of honeycomb diamond 5 is 400 μm. A ventilation channel is formed inside the core layer of the honeycomb diamond 5, and the hollow structure allows air to flow freely, and the thermal conductivity of diamond is excellent, thereby maximizing heat loss. The upper and lower panels of the shielding cover are connected by a nano-silver low-temperature sintering process, wherein the thickness of the silver paste covering between the nickel silver 4 and the honeycomb diamond 5 is 20-70 μm, and the nano-silver particles have an extremely high specific surface area and huge surface energy. When the particles come into contact, the atoms eliminate the surface by diffusion to reduce the total free energy, thereby achieving low-temperature sintering and high-temperature use. The double-layer structure allows electromagnetic waves to pass through the "absorption-conduction" process, reducing the electromagnetic waves reaching the chip 2, thereby achieving the effect of protecting the chip 2. Furthermore, the shielding cover structure has a high specific strength and specific stiffness, so that the stability of the shielding cover is improved. The chip 2 is located on the PCB inside the package. The honeycomb diamond shield is used to protect the chip 2 from interference from internal and external electromagnetic waves and to improve its heat dissipation performance.

[0025] The specific implementation steps of the present invention are as follows: Step 1: Prepare honeycomb diamond nickel silver shield. First, cut the nickel silver into the corresponding size and shape, then: (1) Select a Mo substrate with a thickness of 20~40mm. The substrate surface should be free of cracks.

[0026] (2) Pre-grind the Mo substrate with W20 diamond powder until there are no large scratches on the surface of the Mo substrate, and then ultrasonically clean the Mo substrate.

[0027] (3) Control the substrate temperature between 900~1000℃ and keep it stable.

[0028] (4) Keep the plasma torch input power as high as possible.

[0029] (5) While ensuring an appropriate diamond growth rate, CH 4 The concentration should be as small as possible, generally CH 4 / H 2 =1%~1.5%.

[0030] (6) The overall integrity of the obtained diamond layer is tested under ultrasonic scanning.

[0031] Diamonds were obtained by the laboratory DC arc plasma jet CVD method, and the surface roughness was less than 10nm after grinding and polishing. The diamonds were then cut into thin layers with a thickness of 400μm, and a honeycomb core shape with a side length of 100μm was laser cut on the surface to form a honeycomb core layer diamond.

[0032] Step 2: Connect nickel silver and honeycomb diamond.

[0033] (1) Select a silver paste made of a mixture of nano-sized silver particles, micron-sized silver particles and resin material and a clean surgical blade.

[0034] (2) The honeycomb diamond and nickel silver sheets were ultrasonically cleaned in acetone and deionized water for 5 min respectively to remove surface contaminants.

[0035] (3) Use a surgical blade to coat a certain thickness of silver paste (20~70μm) on the surface of nickel silver and honeycomb diamond.

[0036] (4) Place the nickel silver and honeycomb diamond coated with silver paste in a hot press, heat it to 160°C and keep it warm for 30 minutes, then take out the sample, press it at 50 kPa for 30 minutes, and then quickly heat it to 200°C for sintering.

[0037] (5) After sintering, check whether there is any silver paste overflowing from the side of the shielding cover.

[0038] Step 3: Install the shielding cover on the PCB chip. This shielding cover can provide a stable working environment for the chip, ensure the normal use of the chip, improve the performance of the chip and extend its service life.

[0039] Step 4: Nickel silver-honeycomb diamond undergoes an "absorption-conduction" process. The heat is transmitted from bottom to top, and the heat is transferred from the inside of the chip to the upper nickel silver through the lower honeycomb diamond, which greatly reduces the temperature inside the chip, thereby ensuring the normal use of the chip, providing it with a stable working environment and extending its service life. Nickel silver has extremely high electromagnetic shielding performance, which can shield the electromagnetic interference and electromagnetic signals generated by the chip during use. At the same time, the excellent thermal conductivity of diamond can improve the heat dissipation efficiency of the chip.

[0040] In summary, the honeycomb diamond optical module shielding cover of the present invention and its preparation process, wherein the honeycomb diamond is first obtained by a DC arc plasma jet CVD method, and then a honeycomb core shape with a side length of 100 μm is laser cut on its surface, thereby forming a honeycomb core layer diamond, and nickel silver and honeycomb diamond are connected by a nano-silver low-temperature sintering process. The honeycomb diamond shielding cover forms a double-layer structure so that the electromagnetic signal undergoes the "absorption-conduction" process and greatly reduces the impact of the electromagnetic signal on the chip. Since the honeycomb diamond has many honeycomb units and the diamond has excellent thermal conductivity, it is conducive to forming a ventilation channel, and the hollow structure allows the air to flow freely, and the heat generated inside the chip is quickly conducted to the outside of the shielding cover, thereby maximizing the heat loss and reducing the damage to the chip. At the same time, the thermal expansion coefficients of diamond and nickel silver are not much different, so the function of the shielding cover will not be affected during use. Nickel silver shields the interference of external electromagnetic waves on the chip, and the honeycomb diamond improves the heat dissipation performance of the chip, thereby providing a stable working environment for the chip and extending the service life of the chip.

[0041] The beneficial effects of the present invention are as follows: According to the present invention, a honeycomb diamond optical module shielding cover and its preparation process are composed of two parts: an upper panel nickel silver and a lower panel honeycomb diamond core layer. Nickel silver has excellent electromagnetic shielding ability and thermal conductivity, can greatly reduce the impact of electromagnetic radiation and electromagnetic signals reaching the chip on the chip, and improve the heat dissipation capacity. There are many small honeycomb units inside the honeycomb diamond layer structure, and ventilation channels are formed between these small units, which are conducive to the free flow of air. When the material is heated, the air flows in these channels and takes away the heat from the surface of the material. Such a structure has high specific strength and specific stiffness. The upper and lower panels almost provide all the bending stiffness and tensile stiffness in the plane of the structure, and also play a role in stabilizing the upper and lower panels and preventing local buckling, and has stability. At the same time, the electromagnetic shielding property of the composite material is significantly improved. The design of the sandwich structure allows electromagnetic waves to undergo an absorption-conduction process when passing through the composite material, so that the absorption and shielding efficiency is significantly improved.

[0042] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0043] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A honeycomb diamond optical module shielding cover, characterized in that: include: Double-layer structure; The upper layer of the double-layer structure is a metal sheet; the lower layer of the double-layer structure is a honeycomb diamond; the metal sheet and the honeycomb diamond are connected by a nano-silver low-temperature sintering process; the honeycomb diamond includes a plurality of honeycomb units connected to each other; ventilation channels are formed between the honeycomb units; The honeycomb diamond is a hollow rectangular structure; the front, top and rear surfaces of the rectangular structure are all rectangles of 3mm×5mm, and the left and right surfaces of the rectangular structure are both squares of 3mm×3mm; the material of the metal sheet is nickel silver.

2. The honeycomb diamond optical module shielding cover according to claim 1, characterized in that: The thickness of the metal sheet is 600 μm, and the thickness of the honeycomb diamond is 400 μm.

3. The honeycomb diamond optical module shielding cover according to claim 1, characterized in that: The preparation material of the honeycomb diamond is diamond.

4. The honeycomb diamond optical module shielding cover according to claim 3, characterized in that: The diamond is grown in a laboratory by chemical vapor deposition.

5. The honeycomb diamond optical module shielding cover according to claim 3, characterized in that: The honeycomb diamond is obtained by laser cutting the diamond surface into a honeycomb core shape and then grinding and polishing it.

6. The honeycomb diamond optical module shielding cover according to claim 5, characterized in that: The surface roughness of the honeycomb diamond after grinding and polishing is less than 10 nm.

7. A method for preparing a honeycomb diamond optical module shielding cover, characterized in that: include: The obtained metal sheet is used as the upper layer, the obtained honeycomb diamond is used as the lower layer, and the upper layer and the lower layer are connected by using a nano-silver low-temperature sintering process to obtain a double-layer structure.

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