Wettable side wing package substrate and method of processing the same

Abstract

The application discloses a wettable side wing packaging substrate and a processing method thereof. The processing method comprises the following steps: an operation board is provided with an insulating intermediate layer, an inner layer circuit layer and an outer layer copper foil; a plurality of blind grooves are processed on the operation board through a CCD depth control milling technology, the groove opening of the blind groove is opened on the outer layer copper foil, and the groove bottom is recessed on the insulating intermediate layer; the groove bottom and the groove sidewall of the blind groove are subjected to a metalization treatment, so as to cover the metal base layer on the groove bottom and the groove sidewall of the blind groove; the outer layer circuit is made on the outer layer copper foil; the metal base layer arranged on the groove bottom is subjected to local etching, so as to process a cutting window on the metal base layer, and the cutting window also divides the remaining metal base layer on the groove bottom into two parts which are not connected with each other; and the surface treatment is performed on the metal base layer and the outer layer circuit after the solder mask, so as to obtain the wettable side wing packaging substrate. The processing method is simple and reasonable, and the processing precision is very high, so that the processing quality and the processing efficiency of the obtained packaging substrate are very high.

Description

Technical Field

[0001] This invention relates to the field of circuit board technology, and in particular to a wettable side-wing packaging substrate and its processing method. Background Technology

[0002] Currently, the following packaging processes are commonly used in the manufacturing of through-hole power management products: 1) Through-hole packaging technology; Through-hole packaging allows electronic components to be directly inserted into holes or slots on a circuit board, simplifying the wiring and design process. However, existing through-hole packaging typically requires a large space and through-holes, which significantly limits the space available for dense wiring and the miniaturization of individual components. Therefore, existing through-hole packaging is not well-suited for applications requiring high integration.

[0003] 2) Pin sidewall metallization semi-blind via packaging substrate process; The packaging substrate process includes sequential steps such as preparation board → laser burning of blind trenches → tin plating of the whole board → partial etching of the bottom of the trench (to obtain the cutting channel) → outer layer circuitry → solder resist, etc., to produce a packaging substrate with a number of pin half-pieces integrated.

[0004] This packaging substrate process not only effectively solves the problem of existing through-hole connectors occupying double-sided wiring space, facilitating denser wiring in products, but also provides effective three-sided three-dimensional solder wrapping for the pins, improving product performance and reliability. However, this packaging substrate process still has some limitations in actual production implementation, such as: ① Although the processing precision of laser-etched blind trenches is high, it cannot meet the requirements for higher precision processing due to the influence of parameters such as laser power, pulse width, and processing speed; ② Because the entire board is tin-plated first, it is necessary to break the tin before performing local etching of the trench bottom and fabrication of outer layer circuitry, which to some extent increases production costs and reduces processing efficiency.

[0005] In view of this, the present invention is hereby proposed. Summary of the Invention

[0006] To overcome the above-mentioned defects, the present invention provides a wettable side-wing packaging substrate and its processing method. The processing method is simple, reasonable and has very high processing precision, resulting in very high processing quality and efficiency of the obtained wettable side-wing packaging substrate.

[0007] The technical solution adopted by this invention to solve its technical problem is: a processing method for a wettable side-wing packaging substrate, comprising: A work board is provided, wherein an insulating intermediate layer, an inner circuit layer and an outer copper foil are stacked sequentially from the inside to the outside. Multiple blind slots arranged in rows are machined on the working board using CCD deep milling technology. The openings of the multiple blind slots are all open on the outer copper foil, and the bottoms of the slots are all recessed on the insulating intermediate layer. The bottom and sidewalls of the blind groove are metallized to cover the bottom and sidewalls of the blind groove with a metal base layer. An outer layer circuit is fabricated on the outer copper foil; The metal substrate layer disposed on the bottom of the blind groove is partially etched to create a cutting window on the metal substrate layer that exposes a portion of the bottom of the blind groove for subsequent cutting. At the same time, the cutting window also divides the remaining metal substrate layer on the bottom of the blind groove into two unconnected parts. The surface treatment of the metal substrate and the outer circuit after solder resist treatment is performed to obtain the wettable side wing packaging substrate.

[0008] As a further improvement of the present invention, the edge of the working plate is provided with a positioning target; when machining blind grooves using CCD controlled depth milling technology, the CCD controlled depth milling machine positions itself by gripping the positioning target, and simultaneously uses a double-edged end mill, as well as adopts a specific end mill diameter compensation method and end mill depth correction method, so that the groove depth tolerance of the machined blind groove is controlled within ±0.02mm.

[0009] As a further improvement of the present invention, the above-mentioned milling cutter diameter compensation method is as follows: for every 1m traveled by the double-edged end mill, the diameter of the double-edged end mill is compensated by 0.004 to 0.005mm.

[0010] As a further improvement of the present invention, the above-mentioned milling cutter depth correction method is as follows: initially setting the safety height and machining start height of the Z-axis of the CCD depth-controlled milling machine, and leveling the worktable surface of the CCD depth-controlled milling machine by means of probe measurement; The theoretical depth of cut H0 of the double-edged end mill is calculated according to the formula H0=H1+H2+R×L; where H1 is the preset blind groove depth; H2 is the thickness of the backing plate, which is set on the worktable and used to support the work plate; R is the preset diameter compensation rate of the double-edged end mill, and the value of R is 0.004~0.005mm / m; L is the travel distance of the double-edged end mill. The actual depth of cut H3 of the double-edged end mill is calculated according to the formula H3=H0-ΔZ; where ΔZ is the deviation between the actual machining start height of the Z-axis of the CCD depth control milling machine and the initially set machining start height.

[0011] As a further improvement of the present invention, the depth of the blind groove is controlled between 0.03 and 0.3 mm.

[0012] As a further improvement of the present invention, the bottom and sidewalls of the blind tank are metallized by copper plating.

[0013] As a further improvement of the present invention, a method for performing local etching on the metal substrate layer disposed on the bottom of the blind slot includes sequentially performing solder resist pretreatment, printing of resist peelable adhesive, LDI exposure, development, etching and adhesive removal.

[0014] As a further improvement of the present invention, the corrosion-resistant peelable adhesive is PSPI adhesive; the processing parameters for the above-mentioned LDI exposure are: 6 to 8 exposure grids; the processing parameters for the above-mentioned development are: development speed of 1.5 to 2.5 m / s, and development point control at 50% to 60%.

[0015] As a further improvement of the present invention, the thickness of the outer copper foil is 10-15 μm.

[0016] The present invention also provides a wettable side wing packaging substrate, which is manufactured using the processing method of the wettable side wing packaging substrate described in the present invention.

[0017] The beneficial effects of this invention are: ① Compared with conventional blind slot processing technology, this invention uses special CCD controlled depth milling technology to process blind slots, ensuring that the depth tolerance of the blind slots is controlled within ±0.02mm, achieving very high processing accuracy. This provides solid technical support for improving the overall quality of the packaging substrate. ② Compared with the existing technology's processing steps of "plating the entire board with tin first, then fabricating the outer layer circuitry," this invention preferably adopts a processing process of "fabricating the outer layer circuitry first, then performing surface treatment." This ensures the electrical performance of the outer layer circuitry while effectively improving processing efficiency and reducing processing costs by eliminating the need for a tin-breaking process. ③ Compared with the existing technology's process that requires tin-breaking before etching, this invention can directly perform local etching on the metal substrate layer located at the bottom of the blind slot, thereby creating a copper-free cutting window on the metal substrate layer. This avoids the problem of wire drawing (copper wire) during subsequent forming and cutting, and also avoids the problems of long laser tin-breaking processing time and high processing costs, significantly improving the processing quality and efficiency of the packaging substrate. Attached Figure Description

[0018] Figure 1 This is a flowchart of the processing method for the wettable side-wing packaging substrate described in Embodiment 1 of the present invention; Figure 2 This is a cross-sectional view of the work board described in Example 1; Figure 3This is a schematic cross-sectional view of the work plate after a blind groove has been machined in Example 1. Figure 4 This is a schematic cross-sectional view of the bottom and sidewalls of the blind groove after metallization in Example 1. Figure 5 This is a schematic cross-sectional view of the outer layer circuit after it has been fabricated on the outer copper foil of the working board in Example 1. Figure 6 This is a schematic diagram of the cross-sectional structure after a cutting window is machined on the obtained metal substrate layer in Example 1; Figure 7 This is a schematic cross-sectional view of the wettable side-wing packaging substrate obtained in Example 1.

[0019] Referring to the accompanying drawings, the following explanations are provided: 1. Working board; 10. Insulating intermediate layer; 11. Inner circuit layer; 12. Outer copper foil; 13. Insulating reinforcement layer; 120. Outer circuit; 2. Blind slot; 3. Metal base layer; 30. Cutting window; 4. Solder resist layer; 5. Tin layer. Detailed Implementation

[0020] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0021] Example 1:

[0022] Please see the appendix Figure 1 To be continued Figure 7 As shown, this embodiment 1 provides a processing method for a wettable side-wing packaging substrate, including the following processing steps: S1. A working board 1 is provided, wherein the working board 1 is provided with an insulating intermediate layer 10, an inner circuit layer 11 and an outer copper foil layer 12 stacked from the inside to the outside.

[0023] Understandably, depending on the product design requirements, the work board 1 may be equipped with different numbers of inner circuit layers. To facilitate the explanation of the processing method for the wettable side-wing packaging substrate described in this application, this embodiment uses a four-layer board structure as an example.

[0024] For details, please refer to the appendix. Figure 2 As shown, the implementation structure of the working board 1 is as follows: it is provided with an insulating intermediate layer 10, two inner circuit layers 11 respectively fixed on opposite sides of the insulating intermediate layer 10, and two outer copper foils 12 respectively fixed on the two inner circuit layers 11 by insulating reinforcement layers 13.

[0025] Furthermore, the insulating intermediate layer 10 may be, but is not limited to, an FR4 board, and the insulating reinforcement layer 13 may be, but is not limited to, a prepreg.

[0026] The two inner circuit layers 11 and the two outer copper foil layers 12 are electrically connected to each other, and the copper thickness of the two outer copper foil layers 12 is optimally controlled to be 10-15 μm to meet the needs of subsequent processing.

[0027] Supplementary Explanation: Regarding the specific manufacturing method of the aforementioned work board 1, traditional multilayer circuit board manufacturing methods can be adopted. The manufacturing process can be briefly described as follows: Prepare double-sided copper-clad laminate → Drill alignment targets (set on the board edge) → Open windows (etching window opening process can be used) → Drill X-shaped through holes → Fill and plate → Fabricate inner layer circuitry (including pretreatment, coating with photoresist film, LDI exposure, development, etching, and film removal processes) → Lamination (laminate insulating layer and outer copper foil) → Interlayer conduction (including drilling and filling electroplating processes, etc.) → Thickness adjustment of outer copper foil (including grinding and copper reduction processes). Since the above manufacturing process belongs to traditional techniques in the field of circuit board processing technology, it will not be described in detail here.

[0028] S2. Multiple blind slots 2 arranged in rows are machined on the working plate 1 using CCD controlled depth milling technology. The slot openings of the multiple blind slots 2 are all open onto the outer copper foil 12, and the slot bottoms are all recessed into the insulating intermediate layer 10; see appendix for details. Figure 3 As shown.

[0029] As is well known in the field of PCB manufacturing technology, controlled depth milling refers to milling blind slots at specified locations on the PCB to meet design requirements by controlling the depth of CNC cutting. CCD controlled depth milling technology combines CCD vision inspection technology with controlled depth milling technology to achieve high-precision blind slot machining.

[0030] The implementation equipment for CCD controlled depth milling technology is a CCD controlled depth milling machine. Its conventional structure includes a CCD system, a controlled depth milling system, and a detection system. The CCD system includes a CCD camera, lens, and light source, used to acquire surface images of the workpiece (such as the work plate 1) in real time and identify target point positions (such as identifying the position of the alignment target set on the edge of the work plate 1). The controlled depth milling system includes an industrial computer, a main drive unit that integrates X-axis drive modules, Y-axis drive modules, Z-axis drive modules, and R-axis drive modules, and a clamping module set on the execution end of the main drive unit for clamping the cutting tool (such as the double-edged end mill described below). The detection system includes a probe module for detecting surface height, used to verify the authenticity of the height value and assist in compensating for machining path errors. Understandably, when using a CCD depth-controlled milling machine to mill blind grooves, the CCD camera can capture the alignment target information on the work plate 1 and transmit it to the industrial control computer. The industrial control computer analyzes the alignment target image and, in conjunction with the height information fed back by the probe module, controls the main drive device to move, thereby enabling the cutting tool (double-edged end mill) to perform high-precision milling of blind grooves. Additional explanation: The X and Y axis drive modules can drive the cutting tool to move horizontally, the Z axis drive module can drive the cutting tool to move vertically, and the R axis drive module can drive the cutting tool to rotate.

[0031] In order to achieve higher precision in milling blind grooves, this embodiment, when using CCD depth-controlled milling technology to mill blind grooves, in addition to adopting: positioning by grasping the alignment target, feedback of height information by the probe module, and preferably using a double-edged end mill, also adopts a specific end mill diameter compensation method and end mill depth correction method to ensure that the groove depth tolerance of the machined blind groove 2 is controlled within ±0.02mm, that is, to achieve very high milling accuracy in blind grooves.

[0032] Furthermore, the milling cutter diameter compensation method specifically adopted in this embodiment is as follows: after the double-edged end mill travels 1m, the diameter of the double-edged end mill is compensated by 0.004 to 0.005mm. It is understandable that during CCD controlled depth milling, due to manufacturing errors and machining wear, the actual diameter of the milling cutter may differ slightly from the theoretical value set by the program. Therefore, during the milling of blind grooves, this embodiment compensates and corrects the milling cutter diameter in real time to ensure that the dimensions of the machined blind groove meet the design requirements.

[0033] Furthermore, the milling cutter depth correction method specifically adopted in this embodiment is as follows: First, the safety height and machining start height of the Z-axis (Z-axis is the abbreviation of the Z-axis drive module mentioned above) of the CCD depth-controlled milling machine are initially set in the industrial control computer of the depth-controlled milling system, which defines the safety boundary and starting reference for the entire machining process; and the worktable surface of the CCD depth-controlled milling machine is leveled by probe measurement method to ensure machining accuracy; understandably, the above-mentioned probe module can be used to level the worktable surface. Next, the theoretical depth of cut H0 of the double-edged end mill (also known as the milling depth) is calculated according to the formula H0=H1+H2+R×L; where H1 is the preset blind groove depth; H2 is the thickness of the backing plate, which is set on the worktable and used to support the work plate 1; R is the preset diameter compensation rate of the double-edged end mill, and the R value is preferably controlled to be 0.004~0.005mm / m; L is the travel distance of the double-edged end mill. Finally, the actual depth of cut H3 of the double-edged end mill is calculated according to the formula H3=H0-ΔZ; where ΔZ is the deviation between the actual machining start height of the Z-axis of the CCD depth-controlled milling machine and the initially set machining start height mentioned above. It is understood that the actual machining start height of the Z-axis of the CCD depth-controlled milling machine is also obtained by measuring the probe module.

[0034] As can be seen from the above, this embodiment comprehensively considers various factors affecting machining accuracy (such as the flatness of the worktable surface, the thickness of the pad, and the diameter compensation of the double-edged end mill), and adopts a dynamic correction method (such as ΔZ), which significantly improves the machining accuracy of the blind groove 2. This also provides solid technical support for improving the overall quality of the packaging substrate.

[0035] In addition, according to product design requirements, the depth of the blind groove 2 is controlled between 0.03 and 0.3 mm in this embodiment. However, it is understood that this application is not limited to this.

[0036] S3. The bottom and sidewalls of the blind groove 2 are metallized to coat the bottom and sidewalls of the blind groove 2 with a metal substrate layer 3; see appendix for details. Figure 4 As shown.

[0037] Specifically, in this embodiment, a copper plating process is preferably used to metallize the bottom and sidewalls of the blind trench 2; correspondingly, the resulting metal substrate layer 3 is a copper layer. It is understood that metallizing the bottom and sidewalls of the blind trench 2 is to facilitate tin plating on the blind trench 2 in subsequent processes, thereby enabling the packaging substrate to achieve the effect of AVI inspection of solder joints.

[0038] In addition, this embodiment does not impose any restrictions on the thickness of the metal substrate layer 3, and it can be 5 to 10 μm depending on the product design requirements.

[0039] S4. Fabricate the outer layer circuitry 120 on the outer copper foil 12. See the attached document for details. Figure 5 As shown.

[0040] Note: ① This embodiment uses conventional circuit fabrication processes (including pretreatment, coating with photoresist film, LDI exposure, development, etching, and stripping) to fabricate the outer layer circuit 120, so it will not be described in detail here. ② During exposure, the photoresist film covering the blind trench 2 must be exposed to prevent the metal substrate layer 3 on the blind trench 2 from being etched.

[0041] S5. Perform partial etching on the metal substrate layer 3 located on the bottom of the blind groove 2 to create a cutting window 30 on the metal substrate layer 3 that exposes a portion of the bottom of the blind groove 2 for subsequent cutting. Simultaneously, the cutting window 30 divides the remaining metal substrate layer 3 on the bottom of the blind groove 2 into two unconnected parts (see appendix for details). Figure 6 As shown in the figure, it can be understood that the cutting window 30 is a copper-free structure. This can avoid the problem of wire pulling (copper wire) during subsequent forming and cutting, as well as the problems of long laser tin breaking processing time and high processing cost.

[0042] Specifically, in this embodiment, when performing local etching on the metal substrate layer 3 located at the bottom of the blind trench 2, the preferred processing method includes sequentially performing solder resist pretreatment, printing of resist-removable adhesive, LDI exposure, development, etching, and resist removal. Among these steps, The aforementioned pre-weld protection treatment refers to the cleaning and drying of the board.

[0043] The aforementioned printable etch-resistant peelable adhesive refers to the etch-resistant peelable adhesive being printed on the inner wall (including the bottom and side walls of the groove) and the outer layer circuit 120 of the blind groove 2 through a screen printing process (i.e., the etch-resistant peelable adhesive is printed on the entire board); furthermore, the etch-resistant peelable adhesive is preferably PSPI adhesive (photosensitive polyimide).

[0044] The aforementioned LDI exposure and development refer to exposing a portion of the resist-type peelable adhesive according to the work data, and developing away the unexposed portions of the resist-type peelable adhesive. Understandably, through exposure and development, a portion of the metal substrate 3 located at the bottom of the blind tank 2 is exposed. Furthermore, the processing parameters for LDI exposure are: 6 to 8 exposure grids; and the processing parameters for development are: a development speed of 1.5 to 2.5 m / s, with the development point controlled at 50% to 60%.

[0045] The etching mentioned above refers to etching away the portion of the metal substrate 3 exposed outside the corrosion-resistant peelable adhesive to obtain the cutting window 30.

[0046] The aforementioned degumming refers to removing the corrosion-resistant peelable adhesive using an alkaline solution.

[0047] S6. First, solder resist protection is applied to the outer layer circuit 120 to cover the solder resist layer 4 at designated locations on the outer layer circuit 120. Next, surface treatment is performed on the metal substrate layer 3 and the solder resist-treated outer layer circuit 120 to plate a tin layer 5 on both the metal substrate layer 3 and the portions of the outer layer circuit 120 exposed outside the solder resist layer 4. Then, conventional molding, electrical testing, finished product inspection, shipment inspection, and packaging processes are performed to obtain a wettable side-wing packaging substrate. For details, please refer to the appendix. Figure 7 As shown.

[0048] Note: The above-mentioned solder resist and surface treatment operations all adopt conventional technical methods in the field of circuit board technology, so they will not be described in detail here.

[0049] As can be seen from the above, the processing method for the wettable side-wing packaging substrate provided in this application has the following advantages: ① Compared with the conventional blind trench processing technology, this application uses a special CCD controlled depth milling technology to process the blind trench, and ensures that the trench depth tolerance is controlled within ±0.02mm, resulting in very high processing accuracy. This also provides solid technical support for improving the overall quality of the packaging substrate. ② Compared with the existing technology's processing steps of "plating the entire board with tin first, and then fabricating the outer layer circuitry", this application preferably adopts a processing technology of "fabricating the outer layer circuitry first, and then performing surface treatment". This ensures the electrical performance of the outer layer circuitry while effectively improving processing efficiency and reducing processing costs because there is no need for a tin-breaking process. ③ Compared with the existing technology that requires breaking the tin before etching, this application can directly perform local etching on the metal substrate layer 3 located on the bottom of the blind trench 2 to achieve the processing of a copper-free cutting window 30 on the metal substrate layer 3. This can avoid the problem of wire pulling (copper wire) during subsequent forming and cutting, and also avoid the problems of long laser tin breaking processing time and high processing cost, which significantly improves the processing quality and processing efficiency of the packaging substrate.

[0050] Example 2:

[0051] This embodiment 2 provides a wettable side wing packaging substrate, which is manufactured using the processing method of the wettable side wing packaging substrate provided in embodiment 1 above.

[0052] Specifically, the specific structure of the wettable side-wing packaging substrate described in Embodiment 2 is as follows: Please refer to the attached document. Figure 7 The system includes a board body and a blind slot 2. The board body has an insulating intermediate layer 10, two inner circuit layers 11 fixedly disposed on opposite sides of the insulating intermediate layer 10, and two outer circuit layers 120 fixedly disposed on the two inner circuit layers 11 by insulating reinforcement layers 13, and the two inner circuit layers 11 and the two outer circuit layers 120 are electrically connected to each other. The blind slot 2 is formed on the board body, and the slot opening of the blind slot 2 opens onto the outer circuit layer 120, and the slot bottom is recessed into the insulating intermediate layer 10. A coating is also provided on the sidewall of the blind slot 2. The metal substrate 3 extends from one end to the edge of the blind groove 2 and from the other end to the bottom of the blind groove 2. At the same time, the other end of the metal substrate 3 does not completely cover the bottom of the blind groove 2. That is, the other end of the metal substrate 3 is formed into a bifurcated structure. The gap between the bifurcated structures is the cutting window 30 for subsequent cutting processing. In addition, a solder resist layer 4 is provided on a portion of the outer layer circuit 120, and a tin layer 5 is plated on the metal substrate 3 and the portion of the outer layer circuit 120 that is exposed outside the solder resist layer 4.

[0053] As can be seen from the above, the processing quality and processing efficiency of the wettable side-wing packaging substrate obtained in this embodiment 2 are both very high.

[0054] Many specific details have been set forth in the foregoing description to provide a thorough understanding of the present invention. However, the above description is merely a preferred embodiment of the present invention, and the present invention can be implemented in many other ways different from those described herein. Therefore, the present invention is not limited to the specific embodiments disclosed above. Furthermore, any person skilled in the art can make many possible variations and modifications to the technical solutions of the present invention, or modify them into equivalent embodiments, using the methods and techniques disclosed above, without departing from the scope of the present invention. Any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention, without departing from the content of the present invention, shall still fall within the protection scope of the present invention.

Claims

1. A method for processing a wettable side-wing packaging substrate, characterized in that: include: A working board (1) is provided, wherein an insulating intermediate layer (10), an inner circuit layer (11) and an outer copper foil layer (12) are stacked sequentially from the inside to the outside. Multiple blind slots (2) arranged in rows are machined on the working plate (1) using CCD deep milling technology. The openings of the multiple blind slots (2) are all open on the outer copper foil (12), and the bottoms of the slots are all recessed on the insulating intermediate layer (10). The bottom and sidewalls of the blind groove (2) are metallized so that a metal base layer (3) is applied to both the bottom and sidewalls of the blind groove (2). An outer layer circuit (120) is fabricated on the outer copper foil (12); The metal substrate layer (3) located on the bottom of the blind groove (2) is partially etched to create a cutting window (30) on the metal substrate layer (3) that exposes the bottom of the blind groove (2) and is used for subsequent cutting. At the same time, the cutting window (30) also divides the remaining metal substrate layer (3) on the bottom of the blind groove (2) into two unconnected parts. The surface treatment of the metal substrate (3) and the outer circuit (120) after solder resist treatment is performed to obtain the wettable side wing package substrate.

2. The processing method of the wettable side-wing packaging substrate according to claim 1, characterized in that: The working board (1) is provided with alignment targets on its edge; When using CCD depth-controlled milling technology to process blind grooves, the CCD depth-controlled milling machine positions itself by gripping the alignment target, and simultaneously uses a double-edged end mill, as well as adopts a specific milling cutter diameter compensation method and a milling cutter depth correction method, so that the groove depth tolerance of the processed blind groove (2) is controlled within ±0.02mm.

3. The processing method of the wettable side-wing packaging substrate according to claim 2, characterized in that: The above-mentioned milling cutter diameter compensation method is as follows: for every 1m travel distance of the double-edged end mill, the diameter of the double-edged end mill is compensated by 0.004 to 0.005mm.

4. The processing method of the wettable side-wing packaging substrate according to claim 2, characterized in that: The above-mentioned method for correcting the depth of cutter is as follows: The initial settings include the safe height of the Z-axis and the machining start height of the CCD depth-controlled milling machine, as well as the leveling of the worktable surface of the CCD depth-controlled milling machine using a probe measurement method. The theoretical depth of cut H0 of the double-edged end mill is calculated according to the formula H0=H1+H2+R×L; where H1 is the preset blind groove depth; H2 is the thickness of the backing plate, which is set on the worktable and used to support the work plate (1); R is the preset diameter compensation rate of the double-edged end mill, and the value of R is 0.004~0.005mm / m; L is the travel distance of the double-edged end mill. The actual depth of cut H3 of the double-edged end mill is calculated according to the formula H3=H0-ΔZ; where ΔZ is the deviation between the actual machining start height of the Z-axis of the CCD depth control milling machine and the initially set machining start height.

5. The processing method of the wettable side-wing packaging substrate according to claim 2, characterized in that: The depth of the blind groove (2) is controlled between 0.03 and 0.3 mm.

6. The processing method of the wettable side-wing packaging substrate according to claim 1, characterized in that: The bottom and sidewalls of the blind tank (2) are metallized by copper plating.

7. The processing method of the wettable side-wing packaging substrate according to claim 1, characterized in that: A method for performing local etching on the metal substrate layer (3) located on the bottom of the blind groove (2) includes sequentially performing solder resist pretreatment, printing of resist peelable adhesive, LDI exposure, development, etching and adhesive removal.

8. The processing method of the wettable side-wing packaging substrate according to claim 7, characterized in that: The corrosion-resistant peelable adhesive uses PSPI adhesive. The processing parameters for LDI exposure mentioned above are: 6 to 8 exposure frames; The processing parameters for the above-mentioned developing process are: developing speed of 1.5 to 2.5 m / s, and developing point controlled at 50% to 60%.

9. The processing method of the wettable side-wing packaging substrate according to claim 1, characterized in that: The thickness of the outer copper foil (12) is 10-15 μm.

10. A wettable side-wing packaging substrate, characterized in that: It is manufactured using the processing method of the wettable side-wing packaging substrate as described in any one of claims 1 to 9.

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