Manufacturing method of double-sided sandwich aluminum substrate

Abstract

The invention discloses a method for manufacturing a double-sided sandwich aluminum substrate, which comprises the following steps of: taking an aluminum substrate, manufacturing an aluminum substrate through hole, and carrying out nickel electroplating processing; a mold is arranged on the first face, powder filling holes corresponding to the through holes of the aluminum substrate are formed in the mold, and a supporting plate is arranged on the second face; taking resin powder, and filling the resin powder into the through hole of the aluminum substrate; removing the mold, arranging a glue filling plate on the first surface, and carrying out glue filling pressing, etching processing and polishing processing to form an aluminum substrate core plate; respectively arranging circuit substrates on the upper surface and the lower surface of the aluminum substrate core plate, and carrying out pressing, through hole drilling, copper deposition, full-plate electroplating and post-process processing to form a double-sided sandwich aluminum substrate; the resin powder is filled, the supporting plate and the glue filling plate are used for compensation, a good insulating solid hole is formed after glue filling and pressing, the double-face sandwich aluminum substrate is formed through machining, and the related problems that a through hole insulating layer in the hole is hollow and falls off, glue filling is not full, and short circuit occurs are solved.

Description

Technical Field

[0001] The invention relates to the field of circuit board design and processing, and in particular to a method for manufacturing a double-sided sandwich aluminum substrate. Background Art

[0002] In the field of LED, the carrier circuit board is generally required to have high heat dissipation performance to meet the rapid dissipation of heat generated during the working process. Therefore, aluminum-based circuit boards or other metal-based circuit boards are generally used as carrier circuit boards. Traditional aluminum-based circuit boards generally use an insulating layer directly made on the surface of the aluminum substrate, and then use traditional circuit board processing methods to process it into a single-sided aluminum substrate or a double-sided aluminum substrate; or a multi-layer circuit board is pressed on one side of the aluminum substrate, and graphic processing is performed to form an aluminum-based carrier circuit board; aluminum-based circuit boards of these two structures do not have conductive holes that penetrate the aluminum substrate layer, that is, the aluminum substrate only exists as a load-bearing and heat-dissipating function, and does not exist as a form of penetrating conductive holes to increase wiring density, so the wiring density of these two aluminum substrate structures is relatively small.

[0003] However, with the increasing density of products in the fields of LED, the increasing number of functions, and the increasing degree of intelligence, traditional aluminum-based circuit boards can no longer meet application requirements. As a result, double-sided sandwich aluminum substrates have emerged, that is, the aluminum substrate is arranged in the middle layer of the multi-layer circuit board, and the upper and lower surfaces of the aluminum substrate are respectively provided with multi-layer circuit boards, and there are conductive holes penetrating through the aluminum substrate layer to connect the graphic layers of the multi-layer circuit boards on the upper and lower surfaces, which effectively improves the wiring density and expands the design range of the product.

[0004] Since the double-sided sandwich aluminum substrate has a conductive hole that passes through the aluminum substrate layer, and the aluminum substrate does not participate in the electrical connection and conduction of the circuit board, it is necessary to first make an insulating solid hole on the aluminum substrate, and then process the through hole in the solid hole when making the conductive hole, so that an insulating layer is formed between the hole wall of the conductive hole and the aluminum substrate, so as to achieve the effect of electrically connecting the graphic layers of the multi-layer circuit board on the upper and lower sides of the conductive hole without electrically connecting the aluminum substrate.

[0005] At present, solid holes of aluminum substrates are generally processed by resin plugging or press-fitting glue filling.

[0006] However, resin plugging is generally performed on holes with a diameter of 0.2mm to 1.0mm. For holes with a diameter of more than 2.0mm, resin plugging is prone to problems such as resin overflow, plugging voids, and incompleteness. This can easily lead to voids and falling off of the insulating layer in the hole during the subsequent production of through-holes, causing short circuits or no copper in the holes. In addition, the resin plugging process is relatively complicated and the processing efficiency is low, resulting in a relatively high production cost for double-sided sandwich aluminum substrates.

[0007] Press-fit filling is to lay a semi-cured sheet layer on the surface of the aluminum substrate, and press the semi-cured sheet layer into the hole by pressing. This method is generally more suitable for thinner aluminum substrates. For relatively thicker aluminum substrates (for example, the thickness exceeds 1.5mm), the processing difficulty increases exponentially or cannot be processed. Otherwise, problems such as incomplete filling and weak bonding strength of the filling are likely to occur, which may easily lead to the shedding of the insulating layer in the hole and voids when the through-hole is made later. In addition, the pressing filling process is relatively complicated and requires more auxiliary materials, which results in a higher processing cost for the double-sided sandwich aluminum substrate.

[0008] Based on the above background, it is necessary to provide a method for manufacturing a double-sided sandwich aluminum substrate, so as to realize the effective manufacturing of a double-sided sandwich aluminum substrate for different apertures and different aluminum substrate thicknesses. Summary of the invention

[0009] The present invention aims to solve the problems related to the prior art of using resin plugging or press-fitting glue filling to make double-sided sandwich aluminum substrates, which are prone to hollow through-hole insulation layers, falling off, incomplete glue filling, short circuits, etc. in the holes of the double-sided sandwich aluminum substrates. A method for making a double-sided sandwich aluminum substrate is provided, and the method comprises the following steps: S10: taking an aluminum substrate, making an aluminum substrate through hole on the aluminum substrate, and then performing a nickel electroplating process to form a nickel-plated aluminum substrate; S20: a mold is arranged on the first surface of the nickel-plated aluminum substrate, the mold is provided with powder filling holes corresponding to the through holes of the aluminum substrate, and a support plate is arranged on the second surface of the nickel-plated aluminum substrate to form a powder filling structure; resin powder is taken, and the resin powder is filled into the through holes of the aluminum substrate through the powder filling holes to form a powder-filled aluminum substrate; S30: removing the mold, placing a glue-filling plate on the first surface, and performing glue-filling and pressing to form a glue-filled hole aluminum substrate; S40: etching and polishing the aluminum substrate with the glue-filled holes, so that the aluminum substrate through-holes form resin-filled holes, and the aluminum substrate core plate is formed as a whole; S50: The first circuit substrate and the second circuit substrate are respectively arranged on the upper and lower surfaces of the aluminum substrate core board, and the stacking layout is pressed, and through-hole drilling, copper deposition, full-board electroplating and post-processing are performed in sequence to form the double-sided sandwich aluminum substrate.

[0010] Furthermore, the diameter of the through hole of the aluminum substrate is 1.8 mm to 5.0 mm.

[0011] Furthermore, the resin powder is epoxy resin powder or Al2O3 composite epoxy resin powder or AlN composite epoxy resin powder, and the particle size of the resin powder is 1 μm to 100 μm.

[0012] Furthermore, the powder filling hole is a truncated cone-shaped through hole, the smaller bottom surface of the truncated cone-shaped through hole is arranged toward the aluminum substrate through hole, and the diameter of the smaller bottom surface is larger than the diameter of the aluminum substrate through hole.

[0013] Furthermore, the support plate is a single-sided copper-clad plate, and the insulating layer of the single-sided copper-clad plate is arranged toward the surface of the nickel-plated aluminum substrate; the insulating layer of the single-sided copper-clad plate has a glue content greater than 50%.

[0014] Furthermore, the support plate is processed with ventilation holes, and the ventilation holes are arranged corresponding to the through holes of the aluminum substrate and are arranged within the coverage range of the through holes of the aluminum substrate.

[0015] Furthermore, the step of filling the resin powder into the through holes of the aluminum substrate further includes providing a vibration device to the powder filling structure to vibrate during the powder filling process.

[0016] Furthermore, the glue-filled board is a single-sided copper-clad board, and the insulating layer of the single-sided copper-clad board is arranged toward the surface of the nickel-plated aluminum substrate; the glue content of the insulating layer of the single-sided copper-clad board is greater than 50%.

[0017] Furthermore, the glue filling pressing adopts a high-temperature pressing method, the maximum temperature of the high-temperature pressing is 180° C. to 260° C., and the time of maintaining the maximum temperature is 50 minutes to 100 minutes.

[0018] Furthermore, after the integrally formed aluminum substrate core plate, a surface roughening process is required, and the surface roughening is performed by a nylon brush combined with sandblasting, and then chemical micro-etching.

[0019] The technical solution of the present invention improves the hole wall smoothness of the through hole of the aluminum substrate by adopting an electroplated nickel layer, making it easier to achieve subsequent filling with resin powder, and uses the cooperation of the mold and the supporting copper clad plate to form effective filling of the resin powder, thereby preventing problems such as loose filling and voids during the filling process. The support plate and the filling plate are attached to the upper and lower surfaces of the powder-filled aluminum substrate to give the resin powder a certain filling compensation, so that the resin powder can fill the aluminum substrate through-hole more tightly during the filling and pressing process. By roughening the surface of the aluminum substrate and forming a stacked structure with the circuit substrate, stacking and pressing processes are performed to achieve process-oriented processing of the double-sided sandwich aluminum substrate. The overall processing process effectively realizes the through-hole manufacturing process of larger through holes and the high-reliability manufacturing effect, effectively improves the problems related to the through-hole insulation layer being hollow, falling off, incomplete filling, short circuit, etc., and forms a processing technology that is easy to batch process and has good effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] 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 or the description of the prior art 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 the structures shown in these drawings without paying creative work.

[0021] Figure 1 A process diagram of a manufacturing method of a double-sided sandwich aluminum substrate according to an embodiment of the present invention; Figure 2 A schematic diagram of the cross-sectional structure of an aluminum substrate having a nickel-plated layer produced in accordance with an embodiment of the present invention; Figure 3 A schematic diagram of the cross-sectional structure of a powder-filled aluminum substrate produced in accordance with an embodiment of the present invention; Figure 4 A schematic diagram of the cross-sectional structure of an aluminum substrate with glue-filled holes produced in accordance with an embodiment of the present invention; Figure 5 A schematic diagram of the cross-sectional structure of a core plate of an aluminum substrate produced in accordance with an embodiment of the present invention; Figure 6 A schematic diagram of the cross-sectional structure of a double-sided sandwich aluminum substrate for forming a laminated layout according to an embodiment of the present invention; Figure 7 This is a schematic diagram of the cross-sectional structure of a double-sided sandwich aluminum substrate produced according to an embodiment of the present invention.

[0022] Description of Figure Numbers: Label name Label name 10 Nickel-plated aluminum substrate 310 Powder filling hole 100 Aluminum substrate 400 Resin powder 110 Aluminum substrate through hole 30 Aluminum substrate with glue-filled holes 1110 Resin filling holes 500 Glue filling board 120 Nickel plating 510 Second insulation layer 20 Powder filled aluminum substrate 520 Second copper layer 210 First insulation layer 40 Aluminum PCB Core Board 220 First copper layer 610 First circuit substrate 230 Ventilation holes 620 Second circuit substrate 300 Mould 50 Double-sided aluminum sandwich substrate The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. Implementation

[0023] 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.

[0024] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0025] In addition, in the present invention, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0026] See also Figure 1 ; Figure 1 This is a process diagram of a method for manufacturing a double-sided sandwich aluminum substrate according to an embodiment of the present invention.

[0027] The method for manufacturing a double-sided aluminum sandwich substrate provided in an embodiment of the present invention is as follows Figure 1 The processing is carried out according to the process flow of the processing process shown in the figure, and each processing step will be explained step by step below.

[0028] See also Figure 2 ; Figure 2 The cross-sectional structure diagram of a nickel-plated aluminum substrate produced according to an embodiment of the present invention.

[0029] Step S10: Take an aluminum substrate 100, make an aluminum substrate through hole 110 on the aluminum substrate 100, and then perform nickel electroplating to form a nickel-plated aluminum substrate 10. The diameter of the aluminum substrate through hole 110 is 1.8 mm to 5.0 mm; the thickness of the nickel-plated layer 120 formed by nickel electroplating is 4 μm to 10 μm.

[0030] Generally, there needs to be an insulating layer of 20μm to 1.0mm between the copper layer of the hole wall of the through-hole and the aluminum substrate to ensure insulation performance, and the thickness of the insulating layer needs to be selected according to different product types and application requirements; the through-hole in the double-sided sandwich aluminum substrate processed in the embodiment of the present invention can optionally be a through-hole with a larger hole diameter, so the aluminum substrate through-hole 110 also needs to be optionally made into a through-hole with a larger diameter to reserve a space basis for the hole diameter for the subsequently formed insulating layer; the processing of through-holes with larger diameters is more difficult, and the difficulty of making solid holes in the aluminum substrate is also greater, and it is not suitable to use resin plugging or press-fitting filling methods.

[0031] Optionally, the thickness of the aluminum substrate 100 can be selected to be thicker than the thickness of the processed aluminum substrate in the finished double-sided sandwich aluminum substrate. According to the processing requirements, it can be 10μm to 100μm thicker, generally 20μm thicker, which can reserve a reduced thickness compensation value for chemical thinning and grinding during subsequent processing. At the same time, it can provide a pre-large compensation value that can be polished flat for the surface depression of the resin-filled hole formed by the shrinkage of the resin in the hole after the following resin filling processing and glue filling and pressing.

[0032] In order to improve the smoothness of the hole wall of the aluminum substrate through hole 110 and prepare the hole wall conditions for the next step of filling with resin powder, the nickel plating layer should not be too thick, and it is sufficient to have the effect of improving the smoothness of the hole wall.

[0033] See also Figure 3 ; Figure 3 This is a schematic diagram of the cross-sectional structure of a powder-filled aluminum substrate produced according to an embodiment of the present invention.

[0034] Step S20: A mold 300 is set on the first surface of the nickel-plated aluminum substrate 10, which is close to the surface. The mold 300 is provided with powder filling holes 310 corresponding to the through holes 110 of the aluminum substrate. A support plate 200 is set on the second surface of the nickel-plated aluminum substrate 10 to form a powder filling structure; resin powder 400 is taken and filled into the through holes 110 of the aluminum substrate through the powder filling holes 310 to form a powder-filled aluminum substrate 20.

[0035] In the embodiment of the present invention, the through hole 110 of the aluminum substrate is first filled with powder and then pressed to form a solid hole by filling resin powder 400. In this step, the mold 300 is matched with the support plate 200 to achieve clamping and powder filling of the through hole 110 of the aluminum substrate.

[0036] The mold 300, the nickel-plated aluminum substrate 10 and the support plate 200 may be fixed by pins or clamps so that the three are closely fitted to form an integral structure to be filled.

[0037] Optionally, the support plate 200 can be first pressed onto the surface of the nickel-plated aluminum substrate 10, and then the mold can be fixed by clamping it with a pin clamp. However, the pressing process is costly and time-consuming, and is generally suitable for high-precision processing requirements. Otherwise, it is not a preferred solution for batch processing.

[0038] The resin powder 400 is epoxy resin powder or Al2O3 composite epoxy resin powder or AlN composite epoxy resin powder, and the particle size of the resin powder 400 is 1 μm to 100 μm.

[0039] Since it is necessary to make an insulating layer for the through-hole in the hole, the resin powder 400 needs to have a higher insulating performance. If the double-sided sandwich aluminum substrate does not have a particularly high requirement for heat dissipation performance, general epoxy resin powder can be used as the resin powder 400 to be filled. If the heat dissipation performance requirement is high, it is necessary to use Al2O3 composite epoxy resin powder or AlN composite epoxy resin powder with higher heat dissipation performance as the resin powder 400 to be filled. The particle size of the resin powder can be selected according to the filling requirements. Generally, 10μm, 15μm, 20μm, 25μm or 30μm can be selected. The particle size should not be too small, otherwise it is easy to cause dust pollution and the processing cost is high. The particle size should not be too large, otherwise it will be difficult to fill or fill the voids and be incomplete.

[0040] The powder filling hole 310 is a truncated cone-shaped through hole, the smaller bottom surface of which faces the aluminum substrate through hole 110 , and the diameter of the smaller bottom surface is larger than the diameter of the aluminum substrate through hole 110 , with a single side larger by 10 μm to 50 μm, preferably larger than 20 μm.

[0041] The truncated cone-shaped hole is provided on the mold 300, which is more conducive to the accurate filling of the resin powder into the aluminum substrate through hole 110, and the diameter of the smaller bottom surface is larger than the diameter of the aluminum substrate through hole 110 on one side, which can prevent the powder filling hole 310 and the aluminum substrate through hole 110 from being offset due to the error of alignment, making it difficult for the resin powder 400 to be filled into the aluminum substrate through hole 110, or causing the problem of incomplete filling due to dead corners. That is, the smaller bottom surface diameter is larger than the diameter of the aluminum substrate through hole 110, which can be understood as compensation reserved for alignment.

[0042] The support plate 200 is a single-sided copper-clad plate, and the insulating layer of the single-sided copper-clad plate is arranged toward the surface of the nickel-plated aluminum substrate 10 .

[0043] In order to distinguish it from the glue-filled board in the following process, the single-sided copper-clad board of the support board 200 is defined as a first single-sided copper-clad board, its insulating layer is defined as a first insulating layer 210 , and its copper layer is defined as a first copper layer 220 .

[0044] The first insulating layer 210 is made of a board layer with a higher glue content, the glue content is greater than 50%, and the thickness is 20μm to 100μm, preferably 30μm or 50μm; the thickness of the first copper layer 220 is 5μm to 35μm, preferably 8μm or 15μm.

[0045] Firstly, the support plate 200 plays a role in sealing the through hole 110 of the aluminum substrate during the filling process of the resin powder 400. Secondly, the support plate 200 also needs to play a part of its own filling role, that is, during the subsequent filling and pressing, the resin powder 400 may be compacted and contracted under the processing conditions of high temperature and high pressure. Therefore, the support plate 200 can provide a certain buffering and filling compensation effect. Therefore, using a single-sided copper clad laminate with a high glue content as the support plate 200, its first insulating layer 210 can be used to provide a buffering effect during the filling and pressing process, and can provide a certain filling compensation effect to the resin filling hole. At the same time, the first copper layer 220 can be used to form a heat conduction, protect the first insulating layer 210, and restrain the first insulating layer 210, so that the first insulating layer can have a more directional effect.

[0046] In addition, the support plate 200 is processed with ventilation holes 230, which are arranged corresponding to the through holes 110 of the aluminum substrate and are arranged within the coverage range of the through holes 110 of the aluminum substrate; there are one or more ventilation holes 230, and the hole diameter is 0.02 mm to 0.20 mm.

[0047] Providing the vent hole 230 can prevent one end of the aluminum substrate through hole 110 from being sealed, so that when the resin powder 400 is filled from the truncated cone-shaped hole into the aluminum substrate through hole 110, the air in the aluminum substrate through hole 110 can be discharged smoothly, preventing the gas in the hole from being blocked and causing problems such as incomplete filling; the vent hole 230 needs to be made into a hole with a smaller diameter to prevent the resin powder 400 from leaking, and can be made into a plurality of holes to prevent a single hole from being blocked and improve the efficiency of filling the resin powder 400.

[0048] Optionally, the resin powder 400 is filled into the through hole 110 of the aluminum substrate, and a vibration device is provided to the powder filling structure to vibrate during the powder filling process.

[0049] The vibration device can be a vibration motor, which is rigidly connected to the powder filling structure or mold 300 or is installed by screws, snap-fitting, adsorption, etc. During the process of filling the resin powder 400, the vibration device is turned on to make the filling tighter and fuller to prevent the powder from getting stuck.

[0050] See also Figure 4 ; Figure 4 The cross-sectional structure diagram of an aluminum substrate with glue-filled holes manufactured according to an embodiment of the present invention is shown.

[0051] Step S30: The mold 300 is removed, and a glue-filling plate 500 is disposed on the first surface, and glue-filling and pressing are performed to form a glue-filled hole aluminum substrate 30 .

[0052] In this step, the glue-filled board 500 is a single-sided copper-clad board, and the insulating layer of the single-sided copper-clad board is arranged toward the surface of the nickel-plated aluminum substrate 10 .

[0053] In order to distinguish it from the supporting board in the above process, the single-sided copper-clad board of the glue-filled board 500 is defined as a second single-sided copper-clad board, its insulating layer is defined as a second insulating layer 510 , and its copper layer is defined as a first copper layer 520 .

[0054] The second insulating layer 510 is made of a board layer with a higher glue content, with a glue content of >50%, and a thickness of 20μm to 100μm, preferably 30μm or 50μm; the thickness of the second copper layer 520 is 5μm to 35μm, preferably 8μm or 15μm.

[0055] After the filling of the resin powder 400 is completed, a protective structure is needed to be given to the resin powder filled so that it can form a glue-filled and pressed layout structure. A single-sided copper clad laminate with a higher glue content is used as the glue-filled board 500. Its principle and function are similar to those of the support board. In addition, the glue-filled board 500 can also serve as a cover for the resin powder 400 that has been filled, forming a stacking board foundation for the subsequent formation of a glue-filled and pressed stacking layout structure. During the refilling and pressing process, a high-temperature pressing method is adopted, with the highest temperature being 180°C to 260°C and the time maintained at the highest temperature being 50 minutes to 100 minutes.

[0056] High-temperature pressing can make the resin powder 400 fully melt, and under the buffering and compensation effect of the first insulating layer 210 and the second insulating layer 510, the resin powder 400 can be changed from powder to solidified state; the pressure of the filling pressing can be selected from 1.2MPa to 3.8MPa according to different product performance requirements and material properties, and the heating rate can be selected from 1.2℃ / min to 2.8℃ / min.

[0057] It is worth mentioning that the lamination layout of the glue filling and pressing can be composed from top to bottom in sequence of the first steel plate layer, the first release layer (PTFE film or PI film, etc.), the first coating layer (polyolefin film, PET film, PP film, etc.), the first aluminum sheet layer, the second release layer (PTFE film or PI film, etc.), the aluminum substrate with glue-filled holes to be pressed, the third release layer (PTFE film or PI film, etc.), the second aluminum sheet layer, the second coating layer (polyolefin film, PET film, PP film, etc.), the fourth release layer (PTFE film or PI film, etc.), and the second steel plate layer, wherein the coating layer can give a good buffer coating effect to the glue filling and pressing process, and the aluminum sheet layer can form a thermal conductive and buffering effect.

[0058] See also Figure 5 ; Figure 5 It is a schematic diagram of the cross-sectional structure of a core plate formed by an aluminum substrate according to an embodiment of the present invention.

[0059] Step S40: The aluminum substrate 30 with the filled holes is etched and polished, and the aluminum substrate through-holes 110 are formed into resin filled holes 1110, and the aluminum substrate core plate 40 is formed as a whole; the polishing is performed by means of a sanding belt grinding plate or a ceramic grinding plate.

[0060] The first copper layer 220 and the second copper layer 520 are removed by etching, the first insulating layer 210 and the second insulating layer 510 are removed by grinding, and the nickel-plated layer 120 on the surface of the aluminum substrate 100 is also removed. Therefore, when a single-sided copper-clad laminate is selected as the support plate 200 and the filler plate 500, the first insulating layer 210 and the second insulating layer 510 should not be too thick, otherwise the difficulty and time of the grinding process will be increased.

[0061] In this step, after the aluminum substrate core plate 40 is integrally formed, surface roughening processing is required. The surface roughening is performed by a nylon brush combined with sandblasting, and then chemical micro-etching.

[0062] The surface of the aluminum substrate core board 40 is roughened to form a rough surface with uniform roughness on the surface of the aluminum substrate, so as to prepare the surface foundation for the next step of lamination layout pressing; a nylon brush is used in combination with sandblasting, and then chemical micro-etching is performed. On the one hand, the mechanical roughening treatment of the brush and sandblasting is used to form a clean and rough surface on the surface of the aluminum substrate and the resin-filled hole 1110, and then chemical micro-etching is used to perform chemical roughening treatment to make the surface roughness more delicate and uniform. Chemical micro-etching can be carried out by acid micro-etching or alkaline micro-etching.

[0063] See also Figure 6 and Figure 7 ; Figure 6 A schematic diagram of the cross-sectional structure of a double-sided sandwich aluminum substrate for forming a laminated layout according to an embodiment of the present invention; Figure 7 This is a schematic diagram of the cross-sectional structure of a double-sided sandwich aluminum substrate produced according to an embodiment of the present invention.

[0064] Step S50: See also Figure 6 , respectively set the first circuit substrate 610 and the second circuit substrate 620 on the upper and lower surfaces of the aluminum substrate core plate 40, and perform lamination layout and pressing, see Figure 7 , through-hole drilling, copper deposition, full-board electroplating and post-processing are performed in sequence to form a double-sided sandwich aluminum substrate 50.

[0065] Through lamination and lamination, the first circuit substrate 610 and the second circuit substrate 620 for actual wiring are pressed onto the upper and lower surfaces of the aluminum substrate core board 40, and then through holes are drilled (resin filling holes 1110), and then copper deposition is performed to attach the copper layer. The entire board is electroplated to make the through holes in the holes conductive, and then optional processing steps such as surface pattern transfer processing, solder mask processing, surface treatment processing, etc. are performed in the post-process to finally form a double-sided sandwich aluminum substrate 50.

[0066] To sum up, the embodiment of the present invention fills the resin powder 400, and uses the support plate 200 and the glue filling plate 500 for auxiliary compensation, and forms the resin-filled hole 1110 through the aluminum substrate through hole 110 through glue filling and pressing, and forms a double-sided sandwich aluminum substrate 50 through lamination and typesetting pressing. The whole process can not only effectively improve the problems related to the voids, falling off, incomplete glue filling, short circuits, etc. of the through-hole insulation layer in the hole, but also the practicality of the production method is strong, and can be applied to the production of double-sided sandwich aluminum substrates 50 with different thicknesses and different hole diameters, and can be easily applied to batch processing.

[0067] It should be noted that, due to the different designs, processing, and application scenarios of circuit boards in the actual processing and application processes, and the circuit board processing is a high-precision processing process, the drawings of this embodiment are only used to illustrate the implementation process of the embodiment. They are structural schematic diagrams of the implementation methods, and do not represent the processing size scale diagram of the actual product, nor do they represent the diagram that is enlarged in proportion according to the actual processing conditions.

[0068] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A method for manufacturing a double-sided sandwich aluminum substrate, the manufacturing method comprising the following steps: S10: taking an aluminum substrate, making an aluminum substrate through hole on the aluminum substrate, and then performing a nickel electroplating process to form a nickel-plated aluminum substrate; S20: a mold is arranged on the first surface of the nickel-plated aluminum substrate, the mold is provided with powder filling holes corresponding to the through holes of the aluminum substrate, and a support plate is arranged on the second surface of the nickel-plated aluminum substrate to form a powder filling structure; resin powder is taken, and the resin powder is filled into the through holes of the aluminum substrate through the powder filling holes to form a powder-filled aluminum substrate; S30: removing the mold, placing a glue-filling plate on the first surface, and performing glue-filling and pressing to form a glue-filled hole aluminum substrate; S40: etching and grinding the aluminum substrate with the glue-filled holes, forming resin-filled holes through the aluminum substrate holes, and forming an aluminum substrate core plate as a whole; S50: The first circuit substrate and the second circuit substrate are respectively arranged on the upper and lower surfaces of the aluminum substrate core board, and the stacking layout is pressed, and through-hole drilling, copper deposition, full-board electroplating and post-processing are performed in sequence to form the double-sided sandwich aluminum substrate.

2. The method for manufacturing a double-sided aluminum sandwich substrate according to claim 1, characterized in that: The diameter of the through hole of the aluminum substrate is 1.8 mm to 5.0 mm.

3. The method for manufacturing a double-sided aluminum sandwich substrate according to claim 1, characterized in that: The resin powder is epoxy resin powder or Al2O3 composite epoxy resin powder or AlN composite epoxy resin powder, and the particle size of the resin powder is 1 μm to 100 μm.

4. The method for manufacturing a double-sided aluminum sandwich substrate according to claim 1, characterized in that: The powder filling hole is a truncated cone-shaped through hole, the smaller bottom surface of the truncated cone-shaped through hole is arranged toward the aluminum substrate through hole, and the diameter of the smaller bottom surface is larger than the diameter of the aluminum substrate through hole.

5. The method for manufacturing a double-sided aluminum sandwich substrate according to claim 1, characterized in that: The support plate is a single-sided copper-clad plate, and the insulating layer of the single-sided copper-clad plate is arranged toward the surface of the nickel-plated aluminum substrate; the insulating layer of the single-sided copper-clad plate has a glue content greater than 50%.

6. The method for manufacturing a double-sided aluminum sandwich substrate according to claim 1, characterized in that: The support plate is processed with ventilation holes, and the ventilation holes are arranged corresponding to the through holes of the aluminum substrate and are arranged within the coverage range of the through holes of the aluminum substrate.

7. The method for manufacturing a double-sided aluminum sandwich substrate according to claim 1, characterized in that: The step of filling the resin powder into the through holes of the aluminum substrate further includes providing a vibration device to the powder filling structure to vibrate during the powder filling process.

8. The method for manufacturing a double-sided aluminum sandwich substrate according to claim 1, characterized in that: The glue-filled board is a single-sided copper-clad board, and the insulating layer of the single-sided copper-clad board is arranged toward the surface of the nickel-plated aluminum substrate; the glue content of the insulating layer of the single-sided copper-clad board is greater than 50%.

9. The method for manufacturing a double-sided aluminum sandwich substrate according to claim 1, characterized in that: The glue filling pressing adopts a high-temperature pressing method, the highest temperature of the high-temperature pressing is 180° C. to 260° C., and the time of maintaining the highest temperature is 50 minutes to 100 minutes.

10. The method for manufacturing a double-sided aluminum sandwich substrate according to claim 1, characterized in that: After the aluminum substrate core plate is integrally formed, surface roughening processing is required, and the surface roughening is performed by a nylon brush combined with sandblasting, and then chemical micro-etching.

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