Packaging structure and packaging method thereof

Abstract

The invention provides a packaging structure and a packaging method thereof, and the method comprises the following steps: providing a substrate which comprises an insulating edge rib region and a conductive function region surrounded by the insulating edge rib region; forming a packaging assembly on the front surface of the conductive function area; forming a back surface conductive layer on the back surface of the insulating edge rib area, wherein the back surface conductive layer is electrically connected with the back surface of the conductive function area; and electrically connecting the back conductive layer with electroplating equipment, executing an electroplating process, and forming a plating layer on the back of the conductive functional area. On the premise of maintaining and even improving the reliability of the product, the dependence of the product on precious metal gold can be remarkably reduced, so that the substrate incoming material cost pressure is effectively relieved, and the cost control bottleneck of current LGA packaging is broken through.

Description

Technical Field

[0001] This invention relates to the field of integrated circuit packaging, and more particularly to a packaging structure and packaging method thereof. Background Technology

[0002] Land Grid Array (LGA) packaging, a crucial component of modern electronic packaging technology, replaces traditional pin structures with its unique grid-like metal contact array design, providing an excellent connectivity solution for high-performance integrated circuits. This packaging technology is widely used in server CPUs, high-performance computing modules, and aerospace electronics, primarily due to its high reliability, excellent heat dissipation, and low insertion / removal forces. LGA packaging reduces stress damage to the PCB board through planar contacts rather than through-pins, while achieving higher contact density to meet the ever-increasing I / O demands of modern processors.

[0003] Traditional LGA packaging technology employs chemical gold plating on the substrate's metal contact array, aiming to leverage gold's superior oxidation and corrosion resistance to ensure connection reliability. The gold plating layer provides a stable contact interface, reducing performance degradation caused by environmental factors, while its high hardness effectively resists damage to the solder joints from mechanical stresses such as vibration and impact.

[0004] In traditional grid array packaging technology, the following basic process is usually followed: First, a substrate with a completed back metallization process is required. The back of the substrate is pre-plated with a gold layer through a chemical plating process. Then, the packaging process is performed on the substrate with the gold layer, which specifically includes assembling, bonding and molding of the packaging components on the front of the substrate, and finally forming a grid array packaging structure.

[0005] However, the aforementioned traditional process has significant cost drawbacks: because the gold plating layer needs to be pre-prepared during the substrate manufacturing stage using a chemical plating process, the gold plating layer structure is already fixed on the back side of the substrate upon arrival. On the one hand, the chemical plating process itself involves multiple complex steps, such as plating solution preparation, pretreatment activation, electroplating deposition, and post-treatment (e.g., plating thickness control, surface passivation), and the high cost of gold materials themselves makes the price of substrates with pre-plated gold layers much higher than that of ordinary substrates without gold plating. On the other hand, as a precious metal, the price of gold fluctuates dramatically due to international market supply and demand. In addition, the trend of miniaturization and integration of electronic devices has driven a continuous increase in the number of contacts in LGA packages (for example, from 775 contacts in the early LGA775 package to over 1700 contacts in the current LGA1700 package). The material consumption and processing time of the gold plating process increase linearly with the number of contacts, leading to a rise in the cost proportion of the substrate. The combination of these factors makes the cost of the substrate a core burden in the product cost of traditional LGA packaging solutions, severely restricting the market competitiveness of packaged products.

[0006] There is an urgent need to develop a new packaging method that can significantly reduce the product's dependence on precious metal gold while maintaining or even improving product reliability, thereby effectively alleviating the pressure of substrate material costs and breaking through the current cost control bottleneck of LGA packaging. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to provide a packaging structure and packaging method that can significantly reduce the product’s dependence on precious metal gold while maintaining or even improving product reliability, thereby effectively alleviating the pressure of substrate material cost and breaking through the current cost control bottleneck of LGA packaging.

[0008] To address the aforementioned problems, the present invention provides a packaging method comprising the following steps: providing a substrate, the substrate including an insulating edge region and a conductive functional region surrounded by the insulating edge region; forming a packaging assembly on the front side of the conductive functional region; forming a back conductive layer on the back side of the insulating edge region, the back conductive layer being electrically connected to the back side of the conductive functional region; electrically connecting the back conductive layer to an electroplating device, performing an electroplating process to form a plating layer on the back side of the conductive functional region.

[0009] In one specific embodiment, the insulating edge reinforcement area is a continuous frame structure.

[0010] In one specific embodiment, the outer contour of the continuous frame structure is a polygon, and the edges of the polygon are connected end to end.

[0011] In one specific embodiment, the insulating edge reinforcement area is a segmented frame structure consisting of multiple sub-segments spaced apart by a gap.

[0012] In one specific embodiment, the step of forming a back conductive layer on the back side of the insulating rib region further includes: forming the back conductive layer on the entire area on the back side of the insulating rib region.

[0013] In one specific embodiment, the step of forming a back conductive layer on the back side of the insulating rib region further includes: forming the back conductive layer on a portion of the back side of the insulating rib region.

[0014] In one specific embodiment, the step of forming the back conductive layer in a portion of the back side of the insulating rib region further includes: forming multiple segments of the back conductive layer spaced apart on the back side of the insulating rib region.

[0015] In one specific embodiment, the distance between two adjacent sections of the back conductive layer is equal.

[0016] In one specific embodiment, the distance between two adjacent sections of the back conductive layer is unequal.

[0017] In one specific embodiment, the step of forming a back conductive layer on the back side of the insulating rib region further includes: forming a front conductive layer on the front side of the insulating rib region, wherein the front conductive layer is electrically connected to the back side of the conductive functional region.

[0018] In one specific embodiment, the step of forming a front conductive layer on the front side of the insulating rib area further includes: forming the front conductive layer on the front side of the insulating rib area by coating, adhesive or sputtering processes.

[0019] In one specific embodiment, the back conductive layer is formed simultaneously with the front conductive layer.

[0020] In one specific embodiment, the front conductive layer and the back conductive layer are directly connected via the side of the substrate, thereby making the front conductive layer electrically connected to the back of the conductive functional area.

[0021] In one specific embodiment, the step of forming a back conductive layer on the back side of the insulating rib area further includes: forming the back conductive layer on the back side of the insulating rib area by a coating, adhesive or sputtering process.

[0022] In one specific embodiment, the step of forming a back conductive layer on the back side of the insulating edge region further includes: forming the back conductive layer on the back edge of the conductive functional region.

[0023] In one specific embodiment, prior to the step of forming a back conductive layer on the back side of the insulating rib region, the method further includes: pre-treating the insulating rib region to enhance the surface energy of the region where the back conductive layer is to be formed.

[0024] In one specific embodiment, the step of electrically connecting the back conductive layer to the electroplating equipment further includes: clamping the insulating edge rib area with the conductive clamp of the electroplating equipment, wherein the conductive clamp is in contact with the back conductive layer.

[0025] In one specific embodiment, the conductive clamp has a minimum clamping width, and the width of the insulating edge rib region is greater than the minimum clamping width of the conductive clamp.

[0026] In one specific embodiment, the width of the back conductive layer is greater than the minimum clamping width of the conductive clip.

[0027] In one specific embodiment, the back side of the conductive functional area has a grid-like metal contact array, which is electrically connected to the back conductive layer.

[0028] In one specific embodiment, the metal contacts of the grid-like metal contact array are electrically connected through conductive lines within the substrate, or through conductive lines disposed on the back side of the substrate.

[0029] In one embodiment, the coating covers the grid-like metal contact array.

[0030] In one specific embodiment, the back conductive layer is one of a copper layer, a silver layer, or an aluminum layer.

[0031] In one specific embodiment, the coating is a non-gold coating.

[0032] In one specific embodiment, the plating layer is a tin plating layer.

[0033] In one specific embodiment, the step of forming an encapsulation assembly on the front side of the conductive functional area further includes: mounting electronic components on the front side of the conductive functional area; molding to form an encapsulation body, the encapsulation body covering the electronic components and covering the front side of the conductive functional area, wherein the insulating edge rib area is not covered by the encapsulation body.

[0034] In one specific embodiment, the step prior to the molding step includes performing a cleaning process.

[0035] In one specific embodiment, after the step of electrically connecting the back conductive layer to the electroplating equipment and performing the electroplating process, the method further includes the following step: cutting to remove the insulating edge rib area and forming multiple independent single-chip encapsulation structures.

[0036] A specific embodiment of the present invention also provides an uncut packaging structure, comprising: a substrate, the substrate including an insulating rib region and a conductive functional region surrounded by the insulating rib region; a packaging assembly disposed on the front side of the conductive functional region; a back conductive layer disposed on the back side of the insulating rib region and electrically connected to the back side of the conductive functional region, the back conductive layer being formed after the packaging assembly is formed; and a plating layer covering the back side of the conductive functional region and the surface of the back conductive layer, the plating layer being electroplated using the back conductive layer as an intermediate layer.

[0037] In one specific embodiment, the insulating edge reinforcement area is a continuous frame structure.

[0038] In one specific embodiment, the insulating edge reinforcement area is a segmented frame structure consisting of multiple sub-segments spaced apart by a gap.

[0039] In one specific embodiment, the back conductive layer is formed in all or part of the back surface of the insulating edge reinforcement area.

[0040] In one specific embodiment, a front conductive layer is further included, which is disposed on the front side of the insulating edge rib area and electrically connected to the back side of the conductive functional area.

[0041] In one specific embodiment, the front conductive layer and the back conductive layer are directly connected via the side of the substrate.

[0042] In one specific embodiment, the back conductive layer is further disposed at the back edge of the conductive functional area.

[0043] In one specific embodiment, the conductive functional area of ​​the substrate has a grid-like metal contact array on its back side, and the plating layer covers the grid-like metal contact array.

[0044] The present invention also provides a packaging structure formed by the aforementioned packaging method, comprising: a substrate, including a front side and a back side disposed opposite to each other, the back side of the substrate having a grid-like metal contact array; a packaging assembly disposed on the front side of the substrate; and a tin plating layer covering the grid-like metal contact array on the back side of the substrate.

[0045] The packaging structure and method provided by this invention use a substrate whose back side is not covered with a plating layer upon arrival (unlike traditional pre-plated gold substrates), effectively reducing the basic cost of the substrate. However, to meet the reliability requirements of the packaging structure for the electrical connection performance of the back side of the conductive functional area, a plating layer needs to be formed on the back side of the conductive functional area. The edge of the substrate is surrounded by an insulating rib area, which itself is not conductive, making it impossible to directly form a plating layer on the back side of the conductive functional area using conventional electroplating processes before and during packaging. To address this technical contradiction, the packaging method provided by this invention forms a back conductive layer on the back side of the insulating rib area of ​​the substrate after forming the packaging assembly on the front side of the conductive functional area. The back conductive layer is electrically connected to the back side of the conductive functional area, allowing it to serve as an effective conductive intermediate layer connected to the electroplating equipment. This conducts the electroplating current to the back side of the conductive functional area, performing the electroplating process and forming the required plating layer in that area. The material of the plating layer can be flexibly selected according to actual reliability requirements, replacing the expensive gold plating layer in traditional processes. The packaging method provided by this invention can significantly reduce the product's dependence on precious metal gold while maintaining or even improving product reliability, thereby effectively alleviating the pressure of substrate material costs and breaking through the current cost control bottleneck of LGA packaging.

[0046] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit the invention. Techniques, methods, and apparatus known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and apparatus should be considered part of the specification. Attached Figure Description

[0047] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0048] Figure 1 This is a schematic diagram of the steps of the encapsulation method provided in the first specific embodiment of the present invention; Figure 2 This is a bottom view of the substrate in the packaging method provided in the first specific embodiment of the present invention; Figure 3 The encapsulation method provided in the first specific embodiment of the present invention is along Figure 2 Schematic diagram of the cross section of line A-A1; Figure 4 This is a top view of the packaging method provided in the first specific embodiment of the present invention after electronic components have been mounted. Figure 5 The encapsulation method provided in the first specific embodiment of the present invention is along Figure 4 Schematic diagram of the cross section of line A-A1; Figure 6 This is a top view of the encapsulation component formed in the encapsulation method provided in the first specific embodiment of the present invention; Figure 7 The encapsulation method provided in the first specific embodiment of the present invention is along Figure 6 Schematic diagram of the cross section of line A-A1; Figure 8 This is a bottom view of the encapsulation method provided in the first specific embodiment of the present invention after the back conductive layer has been formed; Figure 9 The encapsulation method provided in the first specific embodiment of the present invention is along Figure 8 Schematic diagram of the cross section of line A-A1; Figure 10 This is a bottom view of the encapsulation method provided in the first specific embodiment of the present invention after the coating has been formed; Figure 11 The encapsulation method provided in the first specific embodiment of the present invention is along Figure 10 Schematic diagram of the cross section of line A-A1; Figure 12 This is a cross-sectional schematic diagram of a single-chip encapsulation structure formed after cutting in the encapsulation method provided in the first specific embodiment of the present invention; Figure 13 This is a bottom view of the substrate in the packaging method provided in the second specific embodiment of the present invention; Figure 14 This is a bottom view of the encapsulation method provided in the third specific embodiment of the present invention after the back conductive layer has been formed; Figure 15 This is a bottom view of the encapsulation method provided in the fourth specific embodiment of the present invention after the back conductive layer has been formed; Figure 16 This is a bottom view of the packaging method provided in the fifth specific embodiment of the present invention after the back conductive layer has been formed; Figure 17 This is a cross-sectional schematic diagram of the packaging method provided in the sixth specific embodiment of the present invention after forming the back conductive layer and the front conductive layer.

[0049] Explanation of reference numerals in the attached figures: 200. Substrate; 201. Insulating edge reinforcement area; 202. Conductive functional area; 203. Metal contacts; 204. Substrate unit; 2011, sub-segment; 2012: Gap; 300. Encapsulated components; 301. Active devices; 302. Passive components; 303. Plastic sealant; 400, Back conductive layer; 500, coating; 600. Conductive clamp; 700, Front conductive layer; 800, Side conductive layer. Detailed Implementation

[0050] The technical solutions in the embodiments of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0051] Figure 1 This is a schematic diagram of the encapsulation method provided in the first specific embodiment of the present invention. Please refer to [link / reference]. Figure 1 The encapsulation method includes: step S10, providing a substrate, the substrate including an insulating edge rib region and a conductive functional region surrounded by the insulating edge rib region; step S11, forming an encapsulation component on the front side of the conductive functional region; step S12, forming a back conductive layer on the back side of the insulating edge rib region, the back conductive layer being electrically connected to the back side of the conductive functional region; and step S13, electrically connecting the back conductive layer to an electroplating device and performing an electroplating process to form a plating layer on the back side of the conductive functional region.

[0052] The packaging method provided by this invention uses a substrate with no plating layer on the back side upon arrival (unlike traditional pre-plated gold substrates), effectively reducing the basic cost of the substrate. After forming the packaging assembly on the front side of the conductive functional area of ​​the substrate, the packaging method of this invention forms a back conductive layer on the back side of the insulating edge region of the substrate. The back conductive layer is electrically connected to the back side of the conductive functional area, allowing it to serve as an effective conductive intermediate layer connected to the electroplating equipment. This conducts the electroplating current to the back side of the conductive functional area, performing the electroplating process and forming the desired plating layer in that area. This overcomes the defect that plating cannot be performed on the back side of the conductive functional area after the packaging assembly is placed on the substrate. The plating material can be flexibly selected according to actual reliability requirements, replacing the expensive gold plating in traditional processes. The packaging method provided by this invention can significantly reduce the product's dependence on precious metal gold while maintaining or even improving product reliability, thereby effectively alleviating the cost pressure of incoming substrate materials and breaking through the current cost control bottleneck of LGA packaging.

[0053] Figures 2-12 This is a process flow diagram of the packaging method provided in the first specific embodiment of the present invention.

[0054] Please see Figure 1 , Figure 2 and Figure 3 ,in, Figure 2 This is a bottom view of the substrate 200 in the packaging method provided in the first specific embodiment of the present invention. Figure 3 The encapsulation method provided in the first specific embodiment of the present invention is along Figure 2 A cross-sectional schematic diagram of line A-A1 in the middle. Step S10: Provide a substrate 200. The substrate 200 includes an insulating edge rib region 201 and a conductive functional region 202 surrounded by the insulating edge rib region 201.

[0055] The substrate 200 is a grid array packaging substrate. The substrate 200 may include organic substrates, ceramic substrates, high-frequency / high-speed substrates, rigid-flexible substrates, etc. Organic substrates are multilayer board structures prepared using organic materials such as FR-4 (brominated epoxy resin copper clad laminate) and BT resin (bismaleimide triazine resin) as substrates through a prepreg lamination process. Ceramic substrates are high-reliability substrates 200 that use inorganic ceramics such as alumina (Al2O3, CTE approximately 6-7 ppm / °C), aluminum nitride (AlN, CTE approximately 4-5 ppm / °C), or beryllium oxide (BeO, CTE approximately 6-7 ppm / °C) as substrates, and fabricate metal circuit layers using thick-film or thin-film processes. High-frequency / high-speed substrates are special substrates 200 designed with low-loss materials such as polytetrafluoroethylene (PTFE)-based composite dielectrics (e.g., Rogers RT / duroid 6035HTC) and cyanate ester resins (e.g., Taconic TLX-8) as the core, and designed with transmission line structures such as microstrip lines and striplines. The rigid-flexible substrate is a hybrid substrate 200 formed by bonding a rigid organic substrate (such as FR-4) and a flexible polyimide (PI) substrate 200 together through a thermo-pressing process, possessing both rigidity and flexibility. Since different types of substrates have different characteristics, the packaging method of this invention can select substrates 200 with different properties according to the requirements of the packaging structure.

[0056] The substrate 200 includes an insulating rib region 201 and a conductive functional region 202. The conductive functional region 202 is surrounded by the insulating rib region 201, which encircles the conductive functional region 202. The insulating rib region 201 provides radial and axial mechanical support for the conductive functional region 202, preventing deformation or breakage of the conductive functional region 202 due to mechanical stress during the packaging process. The insulating rib region 201 also effectively isolates the conductive functional region 202 from electrical connections with other metal components outside the substrate 200, preventing short circuits or parasitic capacitance / inductance interference and ensuring the integrity of electrical signal transmission.

[0057] The insulating edge reinforcement region 201 serves as a non-functional area of ​​the substrate 200. The surface of the insulating edge reinforcement region 201 is made of a highly insulating material, making it non-conductive. In one specific embodiment, the surface of the insulating edge reinforcement region 201 is covered with an insulating green oil (i.e., a solder resist layer) to protect the substrate 200. This insulating green oil is applied through screen printing or spraying processes, ensuring that the surface of the insulating edge reinforcement region 201 of the substrate 200 is non-conductive. This insulating green oil layer not only prevents the insulation performance of the substrate 200 from degradation due to mechanical friction or chemical corrosion during subsequent processing (such as cutting or electroplating), but also protects the substrate 200 from damage caused by high-temperature solder wetting or external heat sources through its high heat resistance and flame-retardant properties.

[0058] In some specific embodiments, the insulating edge rib region 201 is a continuous frame structure, which provides uniform radial and axial support for the conductive functional region 202.

[0059] As an example, such as Figure 2 As shown, in the first embodiment, the insulating rib region 201 is a continuous frame structure, that is, the insulating rib region 201 presents a closed frame shape. Specifically, the outer contour of the continuous frame structure is a polygon, and the edges of the polygon are connected end to end to form a complete closed loop. For example, in this embodiment, the outer contour of the insulating rib region 201 is a rectangle, and the long and short sides of the rectangle are connected end to end to form a closed structure, thereby providing uniform radial and axial support for the conductive functional region 202.

[0060] In other specific embodiments, the insulating rib region 201 is a segmented frame structure composed of multiple sub-segments spaced apart by a gap. This allows each sub-segment of the insulating rib region 201 to move independently in the direction of thermal expansion of the adjacent material layer when the temperature changes, while retaining the mechanical support and electrical isolation function of the insulating rib. This transforms the "interface stress" originally concentrated in the continuous frame structure into "distributed stress" in each sub-segment, effectively avoiding the impact of deformation of the insulating rib region 201 on the internal conductive functional region 202 during the encapsulation process.

[0061] Furthermore, the gap between two adjacent sub-segments is set according to the actual needs of the substrate 200, so as to effectively avoid the impact of deformation of the insulating rib area 201 on the internal conductive functional area 202 while retaining the mechanical support and electrical isolation function of the insulating rib. The gap between two adjacent sub-segments may be equal or unequal.

[0062] As an example, such as Figure 13 The diagram shown is a bottom view of the substrate 200 in the packaging method provided by the second embodiment of the present invention. In the second embodiment, the insulating rib region 201 is a segmented discontinuous frame structure with gaps 2012. The insulating rib region 201 is divided into multiple independent sub-segments 2011, which are separated from each other by the preset gaps 2012 to form a non-closed frame structure. Specifically, in this embodiment, the outer contour of the insulating rib region 201 is rectangular, and the rectangle has a long side and a short side arranged opposite to each other. Gaps are provided on both the long side and the short side to divide the rectangle into multiple independent sub-segments 2011.

[0063] The conductive functional region 202 is located at the center of the substrate 200. As the core conductive functional region of the packaging structure, it is a key interface for realizing the electrical connection between the semiconductor chip and external circuits (such as PCB boards). The front side of the conductive functional region 202 is fitted with a semiconductor chip using wire bonding, flip-chip bonding, or bump interconnect technology, serving as the mechanical fixation and signal transmission function of the semiconductor chip. The back side of the conductive functional region 202 is used for external electrical connection. A grid-like metal contact array is provided on the back side of the conductive functional region 202. The metal contacts 203 of the grid-like metal contact array serve as electrical connection points for direct contact with external printed circuit boards and other structures. The metal contacts 203 of the grid-like metal contact array are electrically connected through conductive lines within the substrate 200 or through conductive lines disposed on the back side of the substrate 200. For example, in one specific embodiment, the metal contacts 203 are made of nickel-palladium-gold (NiPdAu) composite plating and are arranged with periodic grid spacing. The metal contacts 203 are interconnected with the conductive lines inside the substrate 200 through structures such as laser vias or blind vias embedded in the substrate 200.

[0064] In some specific embodiments, the substrate 200 is a large-sized monolithic plate. After the encapsulation assembly 300 is subsequently formed, the monolithic plate is cut to form multiple independent encapsulation structures. The conductive functional region 202 is divided into multiple matrix-arranged substrate units 204. In subsequent cutting processes, the substrate units 204 can be cut along their boundaries. Each substrate unit 204 and the encapsulation assembly 300 disposed on the substrate unit 204 form a single encapsulation structure.

[0065] Please see Figure 1 , Figure 6 and Figure 7 ,in, Figure 6 This is a top view of the encapsulation component 300 formed in the encapsulation method provided in the first specific embodiment of the present invention. Figure 7 The encapsulation method provided in the first specific embodiment of the present invention is along Figure 6 A cross-sectional schematic diagram of line A-A1 is shown. In step S11, an encapsulation component 300 is formed on the front side of the conductive functional area 202. If the substrate 200 is a large-sized whole board, then in this step, an encapsulation component 300 is provided on the front side of each substrate unit 204. The encapsulation components 300 provided on the front sides of different substrate units 204 can be of the same type or different types.

[0066] As an example, the step of forming the encapsulation component 300 on the front side of the conductive functional region 202 includes: Please see Figure 4 and Figure 5 ,in, Figure 4This is a top view schematic diagram of the packaging method provided in the first specific embodiment of the present invention after electronic components have been mounted. Figure 5 The encapsulation method provided in the first specific embodiment of the present invention is along Figure 4 A cross-sectional schematic diagram of line A-A1, showing electronic components mounted on the front side of the conductive functional area 202.

[0067] The electronic components include active components 301 and passive components 302. The active component 301, serving as the functional core of the package, is typically a chip of various types. Its mounting position is preferably located in the center of the conductive functional area 202, and more preferably aligned with the center of the grid-like metal contact array, to shorten the signal transmission path and optimize heat dissipation. The passive component 302 includes an inductor for signal filtering, a capacitor for power supply decoupling, and a resistor for impedance matching. Its mounting position is typically around the periphery of the active component 301, avoiding thermal diffusion interference with the active component 301 and reducing signal loss through short-distance wiring.

[0068] This step achieves stable electrical connection and mechanical fixation between electronic components and conductive functional areas 202 through a high-precision placement process. Specifically, the placement process uses a high-precision pick-and-place machine, such as a high-speed pick-and-place machine or a high-precision pick-and-place machine, with a placement accuracy of ±20μm. Combined with an optical positioning system, such as CCD vision alignment, it ensures that the electronic components are precisely aligned with the predefined pads or redistribution layer RDL pads on the conductive functional areas 202.

[0069] The mounting process can be selected according to the type of electronic component: For the passive components 302, such as chip resistors, chip capacitors, and chip inductors, surface mount technology (SMT) is usually used, and electrical bonding with the substrate 200 is achieved through solder paste printing, mounting, and reflow soldering. For the active components 301, such as system-on-a-chip (SoC), radio frequency chips, and sensor chips, surface mount technology (SMT) can be used, and bonding with the substrate 200 is achieved through solder paste printing, mounting, and reflow soldering. Alternatively, flip chip bonding or wire bonding can be used, where the chip surface bumps, such as solder balls or gold bumps, are electrically connected to the pads on the surface of the substrate 200, thereby achieving electrical bonding with the substrate 200.

[0070] In one specific embodiment, the passive device 302 can be first disposed on the front side of the conductive functional area 202 of the substrate 200, and the active device 301 can be disposed after the passive device 302 is disposed, so as to avoid the mounting process of the passive device 302 affecting the performance of the active device 301. In one specific embodiment, in the step of disposing of the passive device 302, during the solder paste printing stage of the passive device 302, solder paste containing rosin-based flux (RMA type) or no-clean flux (NC type) is used. After the passive device 302 is disposed and melted and cooled by reflow soldering, a small amount of flux decomposition products (such as organic acids, halide ions), unmelted solder particles (such as solder balls, copper powder) or contaminants (such as dust, organic debris) may remain. If not removed in time, these residues may transfer to the surface of the active device 301 during the subsequent mounting process of the active device 301, or dissolve in the soldering solvent of the active device 301, affecting the reliability of the active device 301.

[0071] The packaging method provided in the specific embodiments of the present invention performs a cleaning process after the solder paste printing, mounting and reflow soldering processes are completed to clean solvent residues, such as by rinsing with deionized water, ultrasonic cleaning or solvent wiping, to completely eliminate the risk of contamination to the active device 301.

[0072] In this specific embodiment, only one passive device 302 and one active device 301 are schematically illustrated. The passive device 302 adopts surface mount technology and achieves electrical bonding with the substrate 200 through solder paste printing, mounting and reflow soldering processes. The active device 301 is flip-mounted on the front side of the substrate 200 through flip-chip soldering.

[0073] Please see Figure 6 and Figure 7 The electronic component is encapsulated to form a molded body 303, which covers the electronic component and the front side of the conductive functional area 202. The insulating edge rib area 201 is not covered by the molded body 303. The molded body 303 and the electronic component together serve as the encapsulation assembly 300.

[0074] After the electronic components are mounted, the encapsulation method enters the molding process. Through injection molding and curing of the molding compound, the encapsulated body 303 is formed on the front side of the conductive functional area 202, ultimately constructing the complete encapsulation assembly 300. The material of the encapsulated body 303 is typically epoxy molding compound (EMC), which is composed of epoxy resin (e.g., bisphenol A type epoxy), curing agent (e.g., acid anhydride), filler (e.g., silica powder), and additives (e.g., flame retardants, coupling agents). For high-frequency or high-power applications, low-loss modified EMC (e.g., adding polyphenylene oxide (PPO) blends) or ceramic-filled EMC (e.g., alumina filler) can be used to optimize dielectric properties or thermal conductivity.

[0075] The encapsulation body 303 covers only the front side of the conductive functional region 202 and is flush with or slightly recessed from the edge of the conductive functional region 202, avoiding obstruction of the front side of the insulating rib region 201, thereby avoiding affecting the connection between the subsequent electroplating equipment and the insulating rib region 201. The encapsulation body 303 has good mechanical strength, thermal stability and moisture resistance, and can form a reliable physical protective layer, effectively protecting the internal structure from the influence of the external environment (such as moisture, temperature, contaminants, mechanical stress, etc.), while providing structural support for the encapsulation structure formed by the encapsulation method provided in the specific embodiments of the present invention.

[0076] Optionally, in one embodiment, the molding process further includes a cleaning process before molding. For example, a plasma cleaning process is performed before molding. The cleaning process removes contaminants from the product to ensure quality and roughens the substrate surface to ensure adhesion between the molding compound and the substrate.

[0077] After forming the encapsulation component 300 on the front side of the conductive functional region 202, the encapsulation method performs the following steps: Please see Figure 1 , Figure 8 and Figure 9 ,in, Figure 8 This is a bottom view schematic diagram of the packaging method provided in the first specific embodiment of the present invention after the back conductive layer 400 is formed. Figure 9 The encapsulation method provided in the first specific embodiment of the present invention is along Figure 8A cross-sectional schematic diagram of line A-A1 is shown. In step S12, a back conductive layer 400 is formed on the back side of the insulating edge rib region 201. The back conductive layer 400 is electrically connected to the back side of the conductive functional region 202. The back conductive layer 400 is formed in this step. In the subsequent electroplating step, the back conductive layer 400 enables the electrical connection between the conductive functional region 202 and the electroplating equipment, thereby allowing the electroplating of the conductive functional region 202 to form a plating layer 500.

[0078] In one specific embodiment, the back conductive layer 400 is one of a copper layer, a silver layer, or an aluminum layer.

[0079] In some specific embodiments, the step of forming a back conductive layer 400 on the back side of the insulating edge region 201 further includes: forming a back conductive layer 400 at the back edge of the conductive functional region 202. By forming the back conductive layer 400 at the back edge of the conductive functional region 202, the edge of the back conductive layer 400 overlaps with the edge of the conductive functional region 202, thereby achieving an electrical connection between the back conductive layer 400 and the back side of the conductive functional region 202.

[0080] In some specific embodiments, the step of forming a back conductive layer 400 on the back side of the insulating rib region 201 further includes: forming the back conductive layer 400 on the back side of the insulating rib region 201 by coating, bonding or sputtering processes. The selection of the above different processes depends on the material characteristics of the substrate 200, the performance requirements of the conductive layer and the packaging cost constraints.

[0081] As an example, in a first embodiment, the back conductive layer 400 is formed in the insulating rib region 201 by a sputtering process (e.g., physical vapor deposition, PVD). The edge of the back conductive layer 400 overlaps with the edge of the conductive functional region 202 to achieve electrical connection between the back conductive layer 400 and the back of the conductive functional region 202. This process utilizes high-energy ion bombardment of the target surface to deposit target atoms at a uniform rate in the insulating rib region 201, forming a conductive film with uniform thickness and high density.

[0082] Specifically, the ion deposition characteristics of sputtering effectively suppress thickness deviations caused by material flow or interface defects in traditional processes (such as coating or bonding). Simultaneously, by controlling sputtering power and chamber pressure, the porosity of the conductive layer is reduced, significantly improving density. In subsequent electroplating processes, using this uniform and dense conductive layer as the electroplating current transport layer effectively reduces current fluctuations during electroplating, avoiding problems such as sintering or excessive thinness of the plating layer due to localized excessive current, thus significantly improving the reliability of the packaging structure.

[0083] As an example, in another specific embodiment, a conductive film is attached to the back of the insulating edge rib area 201 as the back conductive layer 400 by an adhesive process. The edge of the conductive film overlaps with the edge of the conductive functional area 202 to achieve electrical connection between the back conductive layer 400 and the back of the conductive functional area 202.

[0084] Specifically, by attaching a pre-cut conductive film to the back of the insulating edge rib area 201 using an adhesive layer such as conductive adhesive, it is beneficial to reduce costs and meet the requirements of ease of operation.

[0085] In one specific embodiment, prior to the step of forming a back conductive layer 400 on the back side of the insulating rib region 201, the method further includes: pre-treating the insulating rib region 201 to enhance the surface energy of the region where the back conductive layer 400 is to be formed.

[0086] Specifically, before forming the back conductive layer 400, the insulating edge rib region 201 is activated, for example by chemical etching or plasma treatment, to enhance the surface energy of the back side of the insulating edge rib region 201, improve the interfacial bonding energy, and increase the bonding strength between the back conductive layer 400 and the back side of the insulating edge rib region 201.

[0087] In one specific embodiment, the step of pre-processing the insulating rib region 201 further includes cleaning the insulating rib region 201.

[0088] During manufacturing or storage, the back side of the insulating rib area 201 is prone to the adhesion of dust, organic residues, or process contaminants. These contaminants can form a "weak interface layer" between the conductive layer on the back and the insulating rib, resulting in poor bonding of the subsequent conductive layer on the back. Therefore, the encapsulation method provided in this embodiment of the invention also includes a step of cleaning the insulating rib area 201. This is achieved through physical cleaning (e.g., ultrasonic cleaning with deionized water), chemical cleaning (e.g., wiping with acetone or ethanol solvent to remove organic contaminants), or a combination of physical and chemical cleaning, to reduce the total amount of contaminants on the back side of the insulating rib area 201 and restore the high cleanliness of the back side of the insulating rib area 201.

[0089] In one specific embodiment, through the synergistic effect of cleaning and decontamination and activation treatment, the surface cleanliness and surface energy of the back side of the insulating rib area 201 are improved in two ways, which solves the interface bonding problem between the back conductive layer 400 and the back side of the insulating rib area 201, and significantly enhances the bonding firmness between the back conductive layer 400 and the back side of the insulating rib area 201.

[0090] In one specific embodiment, the step of forming a back conductive layer 400 on the back side of the insulating rib region 201 further includes: forming the back conductive layer 400 on the entire area of ​​the back side of the insulating rib region 201.

[0091] As an example, such as Figure 8 As shown, in the first embodiment, the back conductive layer 400 covers the entire back surface of the insulating rib region 201, so that the entire back surface of the insulating rib region 201 can be connected to the electroplating equipment. Specifically, the insulating rib region 201 is a continuous frame structure, and the back conductive layer 400 covers the entire back surface of this continuous frame structure.

[0092] As an example, in the second specific implementation, refer to Figure 13 The insulating edge rib region 201 is a segmented discontinuous frame structure with gaps. In the segmented discontinuous frame structure, the back conductive layer 400 is covered on the back of all sub-segments 2011.

[0093] In another specific embodiment, the step of forming a back conductive layer 400 on the back side of the insulating rib region 201 further includes: forming the back conductive layer 400 on a portion of the back side of the insulating rib region 201.

[0094] As an example, such as Figure 14 The diagram shown is a bottom view of the encapsulation method provided in the third embodiment of the present invention after the back conductive layer 400 has been formed. In the third embodiment, the back conductive layer 400 covers a portion of the back side of the insulating rib region 201. Specifically, the insulating rib region 201 is a continuous frame structure, and the back conductive layer 400 covers a portion of the back side of this continuous frame structure. For example, the insulating rib region 201 is a rectangular structure, and the back conductive layer 400 is covered only on one long side of the rectangular structure.

[0095] In another specific implementation, such as Figure 15 The diagram shown is a bottom view of the encapsulation method provided in the fourth embodiment of the present invention after the back conductive layer 400 is formed. In the fourth embodiment, the back conductive layer 400 is covered on the two opposite long sides of the rectangle so that the electroplating equipment can perform electroplating through the long sides of the two rectangles, thereby improving the electroplating efficiency.

[0096] In one specific embodiment, the step of forming the back conductive layer 400 in a portion of the back side of the insulating rib region 201 further includes: forming a plurality of spaced segments of the back conductive layer 400 on the back side of the insulating rib region 201.

[0097] The multiple segments of the back conductive layer 400, spaced apart, break the continuous rigid constraint through the gaps between segments. This allows each segment of the back conductive layer 400 to move independently following the expansion direction of the adjacent material layer when the temperature changes, reducing thermal stress and minimizing interface delamination defects. Furthermore, continuous conductive layers, due to their uniform overall conductivity, are prone to excessively strong electroplating current in localized areas (e.g., at corners), resulting in excessively thick plating layers. In this specific embodiment, the back conductive layer 400, through its segmented and independent design, can be precisely controlled according to the process requirements (e.g., current density, plating thickness) of different segments of the substrate 200 to optimize current distribution and form a uniform plating layer 500.

[0098] As an example, such as Figure 15 As shown, in the fourth specific embodiment, the back conductive layer 400 is covered on the two opposite long sides of the rectangle, forming two sections of the back conductive layer 400. Figure 16 The diagram shown is a bottom view of the packaging method provided in the fifth embodiment of the present invention after the back conductive layer 400 has been formed. In the fifth embodiment, multiple segments of the back conductive layer 400 are spaced apart on the two opposite long sides of the rectangle. In one embodiment, the distance between two adjacent segments of the back conductive layer 400 is equal; in other embodiments, the distance between two adjacent segments of the back conductive layer 400 is unequal to adapt to different process requirements.

[0099] After forming a back conductive layer 400 on the back side of the insulating edge rib region 201, the encapsulation method performs the following steps: Please see Figure 1 , Figure 10 and Figure 11 ,in, Figure 10 This is a bottom view schematic diagram of the encapsulation method provided in the first specific embodiment of the present invention after the plating layer 500 is formed. Figure 11 The encapsulation method provided in the first specific embodiment of the present invention is along Figure 10 A cross-sectional schematic diagram of line A-A1 is shown. In step S13, the back conductive layer 400 is electrically connected to the electroplating equipment, and the electroplating process is performed to form a plating layer 500 on the back of the conductive functional area 202. The plating layer 500 also covers the surface of the back conductive layer 400.

[0100] In this step, the back conductive layer 400 serves as an intermediate layer for electroplating, electrically connecting the electroplating equipment and the conductive functional area 202. During the electroplating process, the electroplating current from the electroplating equipment is conducted through the back conductive layer 400 to the conductive functional area 202, thereby forming a plating layer 500 on the back of the conductive functional area 202. The plating layer 500 protects the back of the conductive functional area 202, improves the product's oxidation and corrosion resistance, increases the hardness of the metal contacts, and reduces damage to the metal contacts caused by mechanical stress (such as vibration and impact).

[0101] In one specific embodiment, the metal contacts on the back side of the conductive functional area 202 are electrically connected through conductive lines in the substrate 200 or through conductive lines disposed on the back side of the substrate 200, so that the back conductive layer 400 only needs to be connected to the metal contacts around the conductive functional area 202 to form the plating layer 500 on all the metal contacts.

[0102] To achieve effective transmission of electroplating current, the back conductive layer 400 needs to be reliably connected to the cathode (or anode, depending on the type of electroplating) of the electroplating equipment via a conductive clip or a dedicated connecting wire. In this specific embodiment, the step of electrically connecting the back conductive layer 400 to the electroplating equipment further includes: clamping the insulating edge rib region 201 with the conductive clip 600 of the electroplating equipment, with the conductive clip 600 in contact with the back conductive layer 400, thereby connecting the back conductive layer 400 to the cathode or anode of the electroplating equipment. Specifically, the conductive clip 600 is used to directly clamp the insulating edge rib region 201, with the conductive clip 600 in contact with the back conductive layer 400. In one specific embodiment, the contact area between the conductive clip 600 and the back conductive layer 400 should not be too small to avoid excessive current density and localized overheating due to an insufficient contact area.

[0103] In one specific embodiment, the conductive clip 600 has a minimum clamping width W1, which refers to the minimum required size of the conductive clip 600 clamping the insulating edge rib area 201. If the size of the conductive clip 600 clamping the insulating edge rib area 201 is smaller than the minimum required size, there may be a risk of detachment during the electroplating process due to uneven force on the conductive clip 600 (such as impact from electroplating solution flow, electrode vibration, or mechanical stress), which will affect the reliability of electroplating.

[0104] In one specific embodiment, to ensure a stable connection between the conductive clip 600 and the insulating rib area 201 during the electroplating process, the width W2 of the insulating rib area 201 is greater than the minimum clamping width W1 of the conductive clip 600, so that the conductive clip 600 and the insulating rib area 201 form a sufficient contact area and clamping force, which can effectively avoid the risk of the conductive clip 600 falling off during the electroplating process.

[0105] In one specific embodiment, the width of the back conductive layer 400 is greater than the minimum clamping width W1 of the conductive clip 600, so as to increase the contact area between the conductive clip 600 and the back conductive layer 400, thereby providing a more stable contact interface for the transmission of electroplating current. This effectively avoids the problem of unstable electroplating current transmission caused by insufficient contact area between the conductive clip 600 and the back conductive layer 400 (such as local suspension or insufficient contact), thereby preventing the generation of defects such as uneven thickness, porosity or insufficient adhesion of the plating layer 500, and improving the reliability of the electroplating process.

[0106] In one specific embodiment, the plating layer 500 is a non-gold plating layer. The plating layer 500 is a tin plating layer. Tin has excellent solderability, and the tin plating layer can act as a protective film to prevent metal from undergoing oxidation, sulfidation, and other corrosion reactions. Furthermore, at soldering temperatures, it can form a strong intermetallic compound with copper foil and other metals on the PCB board, ensuring the stability of the electrical connection. At the same time, tin has a low unit price, far lower than the price of gold, which can effectively reduce product manufacturing costs and meet the requirements of lean manufacturing.

[0107] In some specific embodiments, the substrate 200 is a large, single-piece board. After electrically connecting the back conductive layer 400 to the electroplating equipment and performing the electroplating process, the encapsulation method further includes the following steps: Figure 12 As shown, it is a cross-sectional schematic diagram of a single-encapsulation structure formed after cutting in the encapsulation method provided in the first specific embodiment of the present invention. Cutting is performed to remove the insulating edge rib area 201 and to form multiple independent single-encapsulation structures.

[0108] Cutting processes typically employ either laser cutting or mechanical cutting. For high-precision applications, laser cutting is preferred. A focused high-energy laser beam precisely cuts along the predetermined boundary between the insulating edge region 201 and the conductive functional region 202, as well as the boundary of the substrate unit. The thermal effect of the laser creates a smooth cut surface and avoids thermal damage to adjacent conductive functional regions 202 or the molding compound 303. For mass production, mechanical cutting is used. A high-precision guide rail guides the blade to advance at a constant speed along the predetermined boundary between the insulating edge region 201 and the conductive functional region 202, as well as the boundary of the substrate unit. The sharp edge of the blade cuts off the joint, and a cooling system reduces debris splashing during the cutting process.

[0109] After cutting, the final independent single-chip package structure includes a substrate 200, a package component 300, and a plating layer 500 covering the back of the substrate 200. The insulating edge rib area 201 is completely removed, and the package structures are naturally separated by the cutting surface to meet the needs of subsequent testing, packaging, or assembly.

[0110] In some specific embodiments, the back conductive layer 400 is formed only on the back side of the insulating edge rib region 201, such as... Figure 8 As shown. In some other embodiments, a front conductive layer 700 is also formed on the front side of the insulating edge rib region 201. Specifically, as Figure 17 The diagram shows a cross-sectional view of the encapsulation method provided in the sixth embodiment of the present invention after the formation of the back conductive layer 400 and the front conductive layer 700. In the sixth embodiment, the step of forming the back conductive layer 400 on the back of the insulating rib region 201 further includes: forming the front conductive layer 700 on the front of the insulating rib region 201, wherein the front conductive layer 700 is electrically connected to the back of the conductive functional region 202. In the electroplating step, the electroplating current is conducted to the conductive functional region 202 through the front conductive layer 700 and the back conductive layer 400, greatly increasing the electroplating rate. When the conductive clamp 600 of the electroplating equipment clamps the insulating rib region 201, the conductive clamp 600 can contact the front conductive layer 700 and the back conductive layer 400, increasing the electrical contact area of ​​the conductive clamp 600 and providing a more stable contact interface for the transmission of the electroplating current. In one embodiment, the front conductive layer 700 and the back conductive layer 400 are correspondingly arranged on the front and back of the insulating rib region 201.

[0111] In one specific embodiment, the front conductive layer 700 and the back conductive layer 400 are directly connected via the side of the substrate 200, thereby electrically connecting the front conductive layer 700 to the back of the conductive functional region 202. Specifically, a side conductive layer 800 is formed on the side of the substrate 200, and the front conductive layer 700 and the back conductive layer 400 are connected via the side conductive layer 800, thereby electrically connecting the front conductive layer 700 to the back of the conductive functional region 202 via the back conductive layer 400.

[0112] In one specific embodiment, the step of forming a front conductive layer 700 on the front side of the insulating rib region 201 further includes: forming the front conductive layer 700 on the front side of the insulating rib region 201 by coating, bonding, or sputtering processes. The front conductive layer 700 and the back conductive layer 400 can be formed using the same process. In one specific embodiment, the back conductive layer 400 and the front conductive layer 700 are formed simultaneously, that is, the back conductive layer 400 and the front conductive layer 700 are formed in the same step. For example, a sputtering process is performed, simultaneously forming the front conductive layer 700 and the back conductive layer 400 on the insulating rib region 201.

[0113] The packaging method provided in this invention uses a substrate 200 that is not covered with a plating layer on its back side upon arrival, effectively reducing the basic cost of the substrate 200. After forming the packaging assembly 300 on the front side of the conductive functional area 202 of the substrate 200, a back conductive layer 400 is formed on the back side of the insulating edge region 201 of the substrate 200. The back conductive layer 400 serves as an effective conductive intermediate layer connected to the electroplating equipment, enabling the formation of the required plating layer 500 on the back side of the conductive functional area 202. The material of the plating layer 500 can be flexibly selected according to actual reliability requirements, replacing the expensive gold plating layer in traditional processes. While maintaining or even improving product reliability, it significantly reduces the product's dependence on the precious metal gold, thereby effectively alleviating the cost pressure of the substrate 200 upon arrival.

[0114] Based on the same inventive concept, a specific embodiment of the present invention also provides an uncut packaging structure.

[0115] like Figures 2-11As shown, the uncut packaging structure includes: a substrate 200, the substrate 200 including an insulating rib region 201 and a conductive functional region 202 surrounded by the insulating rib region 201; a packaging assembly 300 disposed on the front side of the conductive functional region 202; a back conductive layer 400 disposed on the back side of the insulating rib region 201 and electrically connected to the back side of the conductive functional region 202, the back conductive layer 400 being formed after the packaging assembly 300 is formed; and a plating layer 500 covering the back side of the conductive functional region 202 and the surface of the back conductive layer 400, the plating layer 500 being electroplated through the back conductive layer 400 as an intermediate layer.

[0116] In one specific embodiment, the insulating rib region 201 is a continuous frame structure, that is, the insulating rib region 201 is a closed frame structure, providing uniform radial and axial support for the conductive functional region 202. In one specific embodiment, as... Figure 2 As shown, the outer contour of the insulating edge rib region 201 is rectangular, and the long side and short side of the rectangle are connected end to end to form a closed structure.

[0117] In another specific embodiment, the insulating edge reinforcement region 201 is a segmented frame structure composed of multiple sub-segments 2011 spaced apart by a gap, such as... Figure 13 As shown, the insulating edge reinforcement area 201 is divided into multiple independent sub-segments 2011, which are separated from each other by a preset gap 2012, forming a non-closed frame structure.

[0118] The back conductive layer 400 is formed over all or part of the back surface of the insulating edge rib region 201. In one specific embodiment, such as... Figure 8 As shown, the back conductive layer 400 covers the entire back surface of the insulating edge rib region 201. In another specific embodiment, as... Figure 14 , Figure 15 and Figure 16 As shown, the back conductive layer 400 covers a portion of the back side of the insulating edge rib region 201.

[0119] In one specific embodiment, the uncut packaging structure further includes a front conductive layer 700, which is disposed on the front side of the insulating rib region 201 and electrically connected to the back side of the conductive functional region 202, such as... Figure 17As shown. In one specific embodiment, the front conductive layer 700 and the back conductive layer 400 are directly connected via the side surface of the substrate 200. Specifically, a side conductive layer 800 is formed on the side surface of the substrate 200, and the front conductive layer 700 and the back conductive layer 400 are connected via the side conductive layer 800, thereby making the front conductive layer 700 electrically connected to the back surface of the conductive functional region 202 through the back conductive layer 400.

[0120] In one specific embodiment, the back conductive layer 400 is further disposed at the back edge of the conductive functional region 202.

[0121] In one specific embodiment, the conductive functional region 202 of the substrate 200 has a grid-like metal contact array on its back side, and the plating layer 500 covers the grid-like metal contact array.

[0122] In the uncut packaging structure provided by the specific embodiments of the present invention, the back conductive layer 400 disposed on the back side of the insulating edge rib region 201 is used as an electroplating intermediate layer, and a plating layer 500 is formed on the back side of the conductive functional region 202. This overcomes the problem that the plating layer 500 cannot be formed on the back side of the conductive functional region 202 after the packaging component 300 is formed. It can significantly reduce the product's dependence on precious metal gold while maintaining or even improving product reliability, thereby effectively alleviating the pressure of raw material cost of substrate 200.

[0123] Based on the same inventive concept, a specific embodiment of the present invention also provides a packaging structure formed using the above-described packaging method, wherein the packaging structure is a single, independent packaging structure formed after cutting. For example... Figures 2-12 As shown, the packaging structure includes: a substrate 200, including a front side and a back side disposed opposite to each other, the back side of the substrate 200 having a grid-like metal contact array; a packaging assembly 300 disposed on the front side of the substrate 200; and a tin plating layer, namely the plating layer 500, covering the grid-like metal contact array on the back side of the substrate 200.

[0124] The packaging structure provided by the specific embodiments of the present invention has low manufacturing cost and is conducive to widespread application.

[0125] The packaging structure and method provided in this invention use a substrate whose back side is not covered with a plating layer upon arrival (unlike traditional pre-plated gold substrates), effectively reducing the basic cost of the substrate. However, to meet the reliability requirements of the packaging structure for the electrical connection performance of the conductive functional areas on the back side, a plating layer needs to be formed on the back side of the conductive functional areas. The edges of the substrate are surrounded by insulating rib areas, which themselves are not conductive, making it impossible to directly form a plating layer on the back side of the conductive functional areas using conventional electroplating processes before and during packaging.

[0126] To address this technical contradiction, the packaging structure and method provided in this invention, after forming the packaging assembly on the front side of the conductive functional area of ​​the substrate, form a back conductive layer on the back side of the insulating edge region of the substrate. The back conductive layer is electrically connected to the back side of the conductive functional area, thus serving as an effective conductive intermediate layer connected to the electroplating equipment. This allows the electroplating current to be conducted to the back side of the conductive functional area, performing the electroplating process and forming the desired plating layer in that area. The material of the plating layer can be flexibly selected according to actual reliability requirements, replacing the expensive gold plating layer in traditional processes.

[0127] The packaging structure and packaging method provided by the specific embodiments of the present invention can significantly reduce the product's dependence on precious metal gold while maintaining or even improving product reliability, thereby effectively alleviating the pressure of substrate material costs and breaking through the current cost control bottleneck of LGA packaging.

[0128] It should be noted that references to "an embodiment," "an embodiment," "an exemplary embodiment," "some embodiments," etc., in the specification indicate that the described embodiments may include specific features, structures, or characteristics, but each embodiment may not necessarily include that specific feature, structure, or characteristic. Furthermore, such phrases do not necessarily refer to the same embodiment. In addition, when a specific feature, structure, or characteristic is described in connection with an embodiment, whether explicitly described or not, implementing such a feature, structure, or characteristic in conjunction with other embodiments is within the knowledge of those skilled in the art.

[0129] It should be noted that the terms "comprising" and "having," and their variations, used in this invention document are intended to cover non-exclusive inclusion. The terms "first," "second," etc., are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence, unless explicitly indicated by the context. It should be understood that such data used interchangeably where appropriate. Furthermore, embodiments and features within embodiments of this invention can be combined with each other unless otherwise specified. In addition, descriptions of well-known components and technologies have been omitted in the above description to avoid unnecessarily obscuring the concepts of this invention. In the various embodiments described above, each embodiment focuses on its differences from other embodiments; similar or identical parts between embodiments can be referred to interchangeably.

[0130] The above description is only a preferred embodiment of the present invention. It should be noted that those skilled in the art can make several improvements and modifications without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A packaging method, characterized in that, Includes the following steps: A substrate is provided, the substrate including an insulating rib region and a conductive functional region surrounded by the insulating rib region; An encapsulation component is formed on the front side of the conductive functional area; A back conductive layer is formed on the back side of the insulating edge rib area, and the back conductive layer is electrically connected to the back side of the conductive functional area. The back conductive layer is electrically connected to the electroplating equipment, and the electroplating process is performed to form a plating layer on the back of the conductive functional area.

2. The packaging method according to claim 1, characterized in that, The insulating edge reinforcement area has a continuous frame structure.

3. The packaging method according to claim 2, characterized in that, The outer contour of the continuous frame structure is a polygon, and the edges of the polygon are connected end to end.

4. The packaging method according to claim 1, characterized in that, The insulating edge reinforcement area is a segmented frame structure consisting of multiple sub-segments spaced apart by a gap.

5. The packaging method according to claim 1, characterized in that, The step of forming a back conductive layer on the back side of the insulating edge rib region further includes: forming the back conductive layer on the entire area on the back side of the insulating edge rib region.

6. The packaging method according to claim 1, characterized in that, The step of forming a back conductive layer on the back side of the insulating edge rib region further includes: forming the back conductive layer on a portion of the back side of the insulating edge rib region.

7. The packaging method according to claim 6, characterized in that, The step of forming the back conductive layer in a portion of the back side of the insulating rib area further includes: forming multiple segments of the back conductive layer spaced apart on the back side of the insulating rib area.

8. The packaging method according to claim 7, characterized in that, The distance between two adjacent sections of the back conductive layer is equal.

9. The packaging method according to claim 7, characterized in that, The distance between two adjacent sections of the back conductive layer is not equal.

10. The packaging method according to claim 1, characterized in that, The step of forming a back conductive layer on the back side of the insulating edge rib region further includes: forming a front conductive layer on the front side of the insulating edge rib region, wherein the front conductive layer is electrically connected to the back side of the conductive functional region.

11. The packaging method according to claim 10, characterized in that, The step of forming a front conductive layer on the front side of the insulating edge rib area further includes: forming the front conductive layer on the front side of the insulating edge rib area by coating, adhesive or sputtering processes.

12. The packaging method according to claim 10, characterized in that, The back conductive layer is formed simultaneously with the front conductive layer.

13. The packaging method according to claim 10, characterized in that, The front conductive layer and the back conductive layer are directly connected via the side of the substrate, thereby making the front conductive layer electrically connected to the back of the conductive functional area.

14. The packaging method according to claim 1, characterized in that, The step of forming a back conductive layer on the back side of the insulating edge rib area further includes: forming the back conductive layer on the back side of the insulating edge rib area by coating, adhesive or sputtering processes.

15. The packaging method according to claim 1, characterized in that, The step of forming a back conductive layer on the back side of the insulating edge region further includes: forming the back conductive layer on the back edge of the conductive functional region.

16. The packaging method according to claim 1, characterized in that, Prior to the step of forming a back conductive layer on the back side of the insulating rib region, the method further includes: pre-treating the insulating rib region to enhance the surface energy of the region where the back conductive layer is to be formed.

17. The packaging method according to claim 1, characterized in that, The step of electrically connecting the back conductive layer to the electroplating equipment further includes: clamping the insulating edge rib area with the conductive clamp of the electroplating equipment, wherein the conductive clamp is in contact with the back conductive layer.

18. The packaging method according to claim 17, characterized in that, The conductive clamp has a minimum clamping width, and the width of the insulating edge rib area is greater than the minimum clamping width of the conductive clamp.

19. The packaging method according to claim 18, characterized in that, The width of the back conductive layer is greater than the minimum clamping width of the conductive clip.

20. The packaging method according to claim 1, characterized in that, The back of the conductive functional area has a grid-like metal contact array, which is electrically connected to the back conductive layer.

21. The packaging method according to claim 20, characterized in that, The metal contacts of the grid-like metal contact array are electrically connected through conductive lines within the substrate, or through conductive lines disposed on the back side of the substrate.

22. The packaging method according to claim 20, characterized in that, The coating covers the grid-like metal contact array.

23. The packaging method according to claim 1, characterized in that, The back conductive layer is one of copper, silver, or aluminum.

24. The packaging method according to claim 1, characterized in that, The coating is a non-gold coating.

25. The packaging method according to claim 24, characterized in that, The coating is a tin plating layer.

26. The packaging method according to claim 1, characterized in that, The step of forming an encapsulation component on the front side of the conductive functional region further includes: Electronic components are mounted on the front side of the conductive functional area; The electronic component is encapsulated to form an encapsulated body that covers the electronic component and the front side of the conductive functional area, while the insulating edge area is not covered by the encapsulated body.

27. The packaging method according to claim 26, characterized in that, Before the molding process, the following steps are included: performing a cleaning process.

28. The packaging method according to claim 1, characterized in that, After electrically connecting the back conductive layer to the electroplating equipment and performing the electroplating process, the following steps are also included: cutting to remove the insulating edge rib area and forming multiple independent single-chip encapsulation structures.

29. An uncut packaging structure, characterized in that, include: A substrate, the substrate including an insulating edge rib region and a conductive functional region surrounded by the insulating edge rib region; An encapsulation component is disposed on the front side of the conductive functional area; A back conductive layer is disposed on the back side of the insulating edge rib area and electrically connected to the back side of the conductive functional area. The back conductive layer is fabricated after the encapsulation assembly is formed. A plating layer covers the back side of the conductive functional area and the surface of the back conductive layer, and the plating layer is electroplated by using the back conductive layer as an intermediate layer.

30. The uncut packaging structure according to claim 29, characterized in that, The insulating edge reinforcement area has a continuous frame structure.

31. The uncut packaging structure according to claim 29, characterized in that, The insulating edge reinforcement area is a segmented frame structure consisting of multiple sub-segments spaced apart by a gap.

32. The uncut packaging structure according to claim 29, characterized in that, The back conductive layer is formed in all or part of the back of the insulating edge rib area.

33. The uncut packaging structure according to claim 29, characterized in that, It also includes a front conductive layer, which is disposed on the front side of the insulating edge rib area and electrically connected to the back side of the conductive functional area.

34. The uncut packaging structure according to claim 33, characterized in that, The front conductive layer and the back conductive layer are directly connected via the side of the substrate.

35. The uncut packaging structure according to claim 29, characterized in that, The back conductive layer is also disposed at the back edge of the conductive functional area.

36. The uncut packaging structure according to claim 29, characterized in that, The conductive functional area of ​​the substrate has a grid-like metal contact array on its back side, and the plating layer covers the grid-like metal contact array.

37. A packaging structure formed using the packaging method of claim 28, characterized in that, include: A substrate includes a front side and a back side disposed opposite to each other, wherein the back side of the substrate has a grid-like metal contact array; A packaging component is disposed on the front side of the substrate; A tin-plated layer covers the grid-like metal contact array on the back side of the substrate.

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