Manufacturing method of reconfigurable LPCAMM memory device

Abstract

The invention discloses a manufacturing method of a reconfigurable LPCAMM storage device, and relates to the technical field of production of storage devices, and the manufacturing method of the reconfigurable LPCAMM storage device realizes comprehensive improvement of technical performance, production efficiency and commercial value through an innovative modular hierarchical architecture and process collaborative design. On the basis that the compact characteristic of a traditional LPCAMM is kept, through the dual effects of mechanical guiding and elastic compensation, the sub-board assembly precision is improved, through the collaborative design of a self-compensation contact array of the detachable storage sub-board and a heat dissipation strengthening layer (S200), the ultra-long plugging service life is achieved, and through the combination of three-dimensional microstructure heat dissipation and the phase change heat storage technology, the phase change heat storage performance is improved. The working temperature of the device is reduced, the thermal resistance value is reduced, the thermal management bottleneck of a high-density storage module is broken through, and a complete solution with high reliability, maintainability and cost effectiveness is provided for large-scale application of the LPCAMM technology in emerging markets such as cloud computing terminals and industrial Internet of Things equipment.

Description

Technical Field

[0001] The present invention relates to the technical field of storage device production, in particular to a method for manufacturing a reconfigurable LPCAMM storage device. Background Art

[0002] Traditional laptops typically use SO-DIMMs (Small Outline Dual In-line Memory Modules) or directly soldered LPDDR memory. The former takes up a lot of space, while the latter is difficult to upgrade and has high repair costs. Market demand: With the increasing performance and energy efficiency requirements of thin and light laptops and mobile workstations, a high-performance, low-power, upgradeable, and compact memory solution is needed. LPCAMM (Low Power Compression Attached Memory Module) is a new low-power memory module technology designed to provide a high-performance, low-power, and compact memory solution for mobile computing devices such as laptops and portable workstations. LPCAMM is based on LPDDR (Low Power Double Data Rate) memory technology and combines a modular design to optimize power consumption and space utilization.

[0003] As described in the published patent CN119542158A, with the continuous development and popularization of AI technology, the application scenarios of AIPCs (artificial intelligence computers) have become more extensive, and AIPC shipments are also increasing annually. Compared with traditional computers, AIPCs have higher requirements for convenience and performance. Therefore, AIPC memory modules need to be ultra-thin and have a large capacity to achieve sufficient convenience and performance. The first and second pads are thermally bonded or SMT-bonded to connect the bare chip to the PCB board to form an LPCAMM memory module.

[0004] In summary, existing LPCAMMs usually use a welding process to control thickness, which makes it difficult for users to upgrade storage capacity later. Summary of the Invention

[0005] In order to overcome the above-mentioned shortcomings, the present invention aims to provide a technical solution that can solve the above-mentioned problems.

[0006] To achieve the above object, the present invention provides the following technical solutions: A method for manufacturing a reconfigurable LPCAMM memory device comprises the following steps: S100: preparing a main carrier substrate, forming stepped grooves on both sides of the substrate, and disposing array-type elastic contact terminals at the bottom of the stepped grooves; S200: A detachable storage daughter board is manufactured separately, wherein a self-compensating contact array corresponding to the main substrate is configured on the bottom surface of the daughter board, and a heat dissipation enhancement layer is provided on the top surface; S300: Pre-coat nano-silver conductive adhesive in the assembly groove, and use vacuum lamination equipment to accurately embed the storage sub-board into the main substrate; S400: The daughterboard is temporarily fixed by a mechanical slide rail locking mechanism, and a pressure of 0.5-2MPa is applied to form a three-dimensional conductive network with the conductive adhesive. S500: Gradient curing is performed at a low temperature of 80-120°C to form a reversible physical connection structure; S600: Inject a thermally conductive dielectric composite medium into the gap between the daughter board and the main substrate to complete the modular packaging. As a further solution of the present invention: Step S100 specifically includes: S110: A modified epoxy resin substrate with a thermal expansion coefficient of ≤8 ppm / °C is selected as the main supporting substrate, wherein the substrate contains a glass fiber reinforcement material with a mass fraction of 15%-25%; S120: A CNC milling machine is used to machine stepped grooves with a depth difference of 0.15-0.35mm on both sides of the substrate. The first-level groove has a depth of 0.8-1.2mm and a sidewall inclination angle of 85°-88°. The second-level groove has a depth of 0.5-0.8mm and a laser-etched rough surface of 2-5μm on the sidewall. S130: Selective metallization is performed on the bottom of the stepped groove, forming a 50-80μm thick copper-nickel composite layer through mask sputtering. A micro-stamping process is used to form an array of elastic contact terminals. Each contact has an Ω-shaped arch structure with an arch height of 120-150μm. A 2-5μm nickel-gold composite layer is electroplated on the contact surface, with a surface roughness Ra ≤ 0.1μm. S140: Arrange an anti-overflow barrier structure in the transition area between the first-level groove and the second-level groove. The anti-overflow barrier structure includes a silicone barrier dam with a width of 0.1-0.3 mm set along the edge of the transition area between the first-level groove and the second-level groove, and an adsorption micropore array is distributed at intervals of 100-200 μm at the bottom of the stepped groove.

[0007] As a further solution of the present invention: Step S200 specifically includes: S210: Preparing a detachable storage daughterboard substrate: Aluminum silicon carbide composite material is used as the substrate with a thickness in the range of 0.6-0.9mm. The substrate surface is laser activated to form an array of micron-scale interconnected pits with a diameter of 80-120μm. 2-4 layers of staggered copper-molybdenum alloy conductive foil are laminated on the activated surface. S220: preparing a contact positioning window with a diameter of 150-250 μm on the bottom surface of the daughter board by photolithography; A nickel-cobalt alloy spring pin array was grown using a selective electrodeposition process.

[0008] As a further solution of the present invention: Step S200 further includes: S230: A three-dimensional heat dissipation microstructure with a depth of 0.2-0.4mm is laser-processed on the top surface of the daughterboard, with an array of staggered micropillars and interconnected radiation grooves. Growing a 5-10 μm aluminum nitride thermal conductive layer on the surface of the microstructure by chemical vapor deposition; The matrix material is an expanded graphite skeleton, and the phase change material is a molten salt eutectic mixture; A flexible graphene thermal pad with a thickness of 0.1-0.3 mm is mounted on the surface of the heat dissipation layer.

[0009] As a further solution of the present invention: Step S300 specifically includes: S310: It uses a dual-station rotary vacuum chamber, maintains a working vacuum degree within the range of 10⁻² to 10⁻³ Torr, is equipped with an infrared radiation heating system, has a temperature control accuracy of ±1.5°C, and integrates a high-precision visual positioning system; S320: Use an automatic dispensing machine to perform spiral progressive coating along the stepped groove profile. The adhesive layer thickness is controlled at 80-120μm, with a width tolerance of ±5μm. Immediately after coating, 50-80kHz ultrasonic vibration is applied to eliminate bubble defects.

[0010] As a further solution of the present invention: the step S300 also includes S330: The storage daughter board is grabbed by a vacuum robot arm, and a pre-installed gap of 0.5-1mm is maintained with the main board. Activate the vision positioning system for 3D alignment calibration, identify the fiducial mark points in the groove of the main substrate, and match them with the alignment crosshairs on the bottom surface of the daughter board; A two-stage embedding strategy is used, with the first stage performing coarse positioning at a speed of 0.1-0.3 mm / s, and the second stage switching to micron-level refinement at 0.02-0.05 mm / s; S340: Apply an initial contact pressure of 0.05-0.1 MPa at the moment of contact; Start the gradient pressurization program: the pressure is linearly increased to 0.8 MPa in the first 30 seconds, and the pressure is maintained at 1 MPa for 90 seconds to complete the initial bonding; The infrared heaters were activated synchronously to maintain the substrate temperature at 45-55°C.

[0011] As a further solution of the present invention: Step S400 specifically includes: S410: Equipped with a multi-axis dynamic pressure control system, including: Three independent piezoelectric ceramic drive units, pressure resolution ±0.05MPa; distributed pressure sensor array; Adaptive PID feedback control module; S420: Pre-pressing stage (0-30 seconds): Apply 0.5-0.8 MPa reference pressure along the Z axis and simultaneously activate ±0.2 MPa oscillating pressure along the XY axis; Infiltration stage (31-60 seconds): Increase the Z-axis pressure to 1.2-1.5 MPa and apply a rotational shear stress field; Forming stage (61-90 seconds): Apply 2MPa peak pressure and maintain for 30 seconds, and simultaneously trigger 50kHz micro-vibration.

[0012] As a further solution of the present invention: Step S400 further includes: S430: Adjust pressure parameters through real-time resistance monitoring feedback: When the unit area resistance value is greater than 10mΩ, the local pressure is automatically increased by 0.3MPa; When the standard deviation of the resistance value is ≥0.5mΩ, XY stress compensation is started, and argon protective atmosphere is injected during the pressure holding stage. The pressure unloading adopts a two-step relaxation mode: the first stage is reduced to 0.8MPa at a rate of 0.1MPa / s, and the second stage is completely released at a rate of 0.05MPa / s. S440: Controlling the directional alignment of silver nanoparticles: applying a 1-3T pulsed magnetic field with the magnetic field direction forming a 45° angle with the pressure axis; The silver particles grow in a chain along the Z axis through the synergistic effect of pressure and temperature; The micro-protrusion structure is formed by mold embossing.

[0013] As a further solution of the present invention: Steps S500 and S600 include: S510: Gradient curing process control: Maintaining the first temperature zone for 20-30 minutes in an inert atmosphere activates the initial cross-linking of the nanosilver conductive adhesive; stepwise increasing the temperature to the second temperature zone and applying periodic micro-vibration to eliminate the interface residual stress; cooling to the third temperature zone to complete the curing and form a reversible physically connected micro-grain boundary structure; By controlling the curing cooling rate and holding time, the conductive adhesive layer retains 10-15% elastic deformation space; S520: Reversible interface structure design: Laser-process a micro-groove array on the surface of the cured conductive adhesive layer to form a mechanical interlocking interface; reserve a decoupling groove at the edge of the main substrate; S610: Thermally conductive dielectric composite injection process: modified silicone resin; graded composite of flake boron nitride (diameter-to-thickness ratio 50:1) and spherical alumina; addition of thixotropic fumed silica; A capillary flow guide structure, including a micropillar array and radial drainage grooves, is pre-installed in the gap between the daughter board and the main substrate. The medium is injected synchronously using a multi-point injection needle, and vacuum negative pressure (10⁻¹ Torr) is used to achieve bubble-free filling. The medium penetration front is dynamically monitored, and the injection speed and path are adjusted through pressure feedback. S620: Modular package molding: Irradiate with 365nm wavelength for 10-15 seconds to form a temporary fixed structure; radiate heat from the center of the device to the outer edge to induce directional shrinkage of the dielectric; A micro-anchor array is laser-etched on the outer surface of the package body and coated with an organic-inorganic hybrid coating to achieve IP67-level protection and electromagnetic shielding.

[0014] Compared with the prior art, the present invention has the following beneficial effects: The present invention's reconfigurable LPCAMM memory device manufacturing method achieves comprehensive improvements in technical performance, production efficiency, and commercial value through an innovative modular layered architecture and process collaborative design. While maintaining the compactness of traditional LPCAMM, the dual effects of mechanical guidance and elastic compensation enhance daughterboard assembly precision. The collaborative design of the removable memory daughterboard's self-compensating contact array and heat-dissipating enhancement layer (S200) not only achieves an ultra-long plug-in life, but also reduces device operating temperature and thermal resistance through the combination of three-dimensional microstructure heat dissipation and phase change heat storage technology, breaking through the thermal management bottleneck of high-density memory modules. Through full-process process innovation, this solution improves mass production yield and reduces rework costs without modifying core SMT equipment. Compatible with the existing JEDEC MSL3 standard, this solution provides a complete solution with high reliability, maintainability, and cost-effectiveness for the large-scale application of LPCAMM technology in emerging markets such as cloud computing terminals and industrial IoT devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a workflow diagram of steps S100-S600 in the present invention; Figure 2 is a workflow diagram of steps S110-S140 in the present invention; DETAILED DESCRIPTION The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0016] See also Figure 1-2A method for manufacturing a reconfigurable LPCAMM memory device includes the following steps: S100: preparing a main carrier substrate, forming stepped grooves on both sides of the substrate, and disposing arrays of elastic contact terminals at the bottom of the stepped grooves; S200: separately manufacturing a removable memory daughter board, configuring a self-compensating contact array corresponding to the main substrate on the bottom surface of the daughter board, and disposing a heat dissipation enhancement layer on the top surface; S300: pre-coating nano-silver conductive adhesive in the assembly groove, and accurately embedding the memory daughter board into the main substrate using a vacuum lamination device; S400: temporarily fixing the daughter board using a mechanical slide rail locking mechanism, and simultaneously applying a pressure of 0.5-2MPa to form a three-dimensional conductive network with the conductive adhesive; S500: performing gradient curing in a low-temperature environment of 80-120°C to form a reversible physical connection structure; S600: injecting a thermally conductive dielectric composite medium into the gap between the daughter board and the main substrate to complete the modular packaging. The present invention's reconfigurable LPCAMM memory device manufacturing method achieves comprehensive improvements in technical performance, production efficiency, and commercial value through an innovative modular layered architecture and collaborative process design. First, a composite structural design (S100) of stepped assembly grooves and elastic contact terminals maintains the compactness of traditional LPCAMMs. Through the dual effects of mechanical guidance and elastic compensation, the daughterboard assembly accuracy is improved to ±5μm, while the contact resistance fluctuation range is reduced to ±0.8mΩ, significantly exceeding the ±5mΩ level of traditional soldering processes. Second, the collaborative design of the removable memory daughterboard's self-compensating contact array and heat-strengthening layer (S200) not only achieves an ultra-long plug-in life, but also reduces the device's operating temperature and thermal resistance through the combination of three-dimensional microstructure heat dissipation and phase change heat storage technology, thus breaking through the thermal management bottleneck of high-density memory modules. Furthermore, the process combination of vacuum lamination and nano-silver conductive adhesive (steps S300 and S400) uses gradient pressure control and magnetic field-assisted orientation technology to form a three-dimensional silver chain interconnected network at low temperatures of 80-120°C. The aspect ratio of the conductive path reaches 8:1, and the longitudinal conductivity is as high as 2.5×10 6 The S / m ratio is over 50% higher than that of traditional sintered silver paste, and the interfacial bonding strength exceeds 25 MPa, completely resolving the issue of low-temperature connection reliability. Furthermore, the modular packaging design (step S600) utilizes in-situ filling of a thermally conductive dielectric composite to achieve an electromagnetic shielding effectiveness of ≥60 dB while reducing the daughterboard replacement time to less than 30 seconds, making it feasible for end-users to upgrade storage capacity on-site, meeting industrial standards. Ultimately, this solution, through full-process process innovation, improves mass production yield and reduces rework costs without requiring modifications to core SMT equipment. Compatible with existing JEDEC MSL3 standards, it provides a complete solution that combines high reliability, maintainability, and cost-effectiveness for the large-scale application of LPCAMM technology in emerging markets such as cloud computing terminals and industrial IoT devices.

[0017] In the embodiment of the present invention: The step S100 specifically includes: S110: selecting a modified epoxy resin substrate with a thermal expansion coefficient of ≤8ppm / °C as a main carrier substrate, the substrate containing a glass fiber reinforcement material with a mass fraction of 15%-25%; S120: using a CNC milling machine to machine step-type grooves with a depth difference of 0.15-0.35mm on both sides of the substrate, wherein: the depth of the first-level groove is 0.8-1.2mm, and the side wall inclination angle is controlled at 85°-88°; the depth of the second-level groove is 0.5-0.8mm, and the side wall forms a laser-etched rough surface of 2-5μm; S130: performing selective metallization treatment on the bottom of the step-type groove, and forming a copper-nickel composite layer with a thickness of 50-80μm by mask sputtering, The elastic contact terminal array is formed by a micro-stamping process. A single contact has an Ω-shaped arch structure with an arch height of 120-150μm. A 2-5μm nickel-gold composite layer is electroplated on the contact surface, and the surface roughness Ra≤0.1μm; S140: An anti-overflow barrier structure is arranged in the transition area between the first-level groove and the second-level groove. The anti-overflow barrier structure includes a silicone barrier dam with a width of 0.1-0.3mm set along the edge of the transition area between the first-level groove and the second-level groove, and an adsorption micropore array is distributed at intervals of 100-200μm at the bottom of the stepped groove.

[0018] The main carrier substrate fabrication process significantly improves the assembly accuracy and long-term reliability of LPCAMM memory devices through the coordinated optimization of material innovation and structural design. The use of a modified epoxy resin substrate with a specifically formulated composite glass fiber reinforcement layer not only ensures the substrate's dimensional stability under high-temperature process conditions but also matches the thermal expansion coefficient with the storage daughterboard, effectively suppressing interfacial stress accumulation during thermal cycling. The dual-stage stepped groove, precisely machined using a CNC milling machine, features inclined sidewalls and a depth difference that provide a self-guiding structure for daughterboard assembly and enhance mechanical locking by increasing the sidewall contact area. The Ω-shaped elastic contact terminal array at the bottom of the groove, with its arched geometry and gradient plating, maintains a stable contact pressure distribution during repeated insertion and removal, while also resisting the effects of environmental corrosion on electrical performance. In addition, the composite anti-overflow system composed of the silicone barrier dam at the edge of the groove and the adsorption micropores at the bottom precisely constrains the flow path of the conductive adhesive during the lamination process, avoiding the risk of short circuits caused by overflow of the adhesive while ensuring the uniformity of the adhesive layer thickness. This series of innovative designs not only improves the tolerance of the assembly process, but also lays a solid physical foundation for subsequent reversible connection and modular maintenance, making the overall manufacturing method both high-precision and high-robustness.

[0019] In the embodiment of the present invention: The step S200 specifically includes: S210: Preparing a detachable storage daughterboard substrate: Aluminum silicon carbide composite material is used as the substrate, with a thickness controlled in the range of 0.6-0.9mm. The substrate surface is laser activated to form an array of micron-scale interconnected pits with a diameter of 80-120μm. 2-4 layers of staggered copper-molybdenum alloy conductive foil are laminated on the activated surface. S220: Self-compensating contact array formation process: A contact positioning window with a diameter of 150-250 μm is prepared on the bottom surface of the daughter board by photolithography; A nickel-cobalt alloy spring pin array is grown using a selective electrodeposition process. A single contact has a base diameter of 200±5μm, a height of 300-400μm, a mushroom-shaped contact tip on top, and a curvature radius of R50-80μm. Gradient coating treatment is applied to the contact surface: a 3-5μm hard gold layer (hardness ≥ 200HV) is electroplated on the bottom layer, and a 0.5-1μm diamond-like carbon film (resistivity ≤ 10μΩ·cm) is deposited on the outer layer; This embodiment utilizes innovative design and manufacturing processes for a removable storage daughterboard, comprehensively optimizing the maintainability, electrical performance, and heat dissipation efficiency of LPCAMM memory devices. By employing a composite structure of an aluminum-silicon carbide composite substrate and a copper-molybdenum alloy conductive layer, the daughterboard's thermal expansion compatibility and mechanical stability are significantly improved, effectively suppressing microcracks during repeated plugging and unplugging, significantly extending the module's lifespan. The self-compensating contact array utilizes a spring-pin structure combined with gradient plating technology to ensure low contact resistance while imparting excellent wear and corrosion resistance, maintaining stable electrical connection performance even under high-frequency plugging and unplugging conditions.

[0020] In the embodiment of the present invention: S230: Heat dissipation enhancement layer construction method: The top surface of the daughterboard is laser-machined with a 0.2-0.4mm deep three-dimensional heat dissipation microstructure, a staggered array of micropillars (100μm diameter, 200μm pitch), and interconnected radiation grooves (50μm width, aspect ratio 1:5). Growing a 5-10 μm aluminum nitride thermal conductive layer on the surface of the microstructure by chemical vapor deposition; The vacuum impregnation process is used to fill the phase change thermal conductive medium: The matrix material is expanded graphite skeleton, and the phase change material is molten salt eutectic mixture (phase change temperature 60-80℃); A flexible graphene thermal pad with a thickness of 0.1-0.3 mm is mounted on the surface of the heat dissipation layer.

[0021] The collaborative design of a three-dimensional heat dissipation microstructure and a phase-change thermal conductive medium significantly improves the heat dissipation efficiency of the daughterboard under high-load operation by increasing the heat dissipation surface area and dynamically adjusting the thermal capacity, thereby preventing performance degradation caused by localized overheating. The introduction of a flexible graphene thermal pad further optimizes the interfacial heat conduction path, enabling overall heat dissipation capabilities to exceed the limitations of traditional packaging. This solution not only enables rapid and lossless replacement of daughterboards, but also ensures long-term reliability through multiple technological innovations. It provides a hardware foundation that combines high performance and ease of use for end users to independently upgrade storage capacity, while also reducing maintenance costs throughout the entire lifecycle.

[0022] In the embodiment of the present invention: The step S300 specifically includes: S310: Vacuum lamination equipment configuration: It uses a double-station rotary vacuum chamber, maintaining a working vacuum degree within the range of 10⁻²~10⁻³ Torr, equipped with an infrared radiation heating system, temperature control accuracy of ±1.5°C, and an integrated high-precision visual positioning system (positioning error ≤3μm); S320: Nano silver conductive adhesive pre-coating process: Use an automatic dispensing machine to perform spiral progressive coating along the stepped groove profile. The adhesive layer thickness is controlled at 80-120μm, with a width tolerance of ±5μm. Immediately after coating, 50-80kHz ultrasonic vibration is applied to eliminate bubble defects.

[0023] This embodiment significantly improves the assembly accuracy and connection reliability of LPCAMM memory devices through optimized design and intelligent control of the vacuum lamination process. A high-precision visual positioning system, working in conjunction with a vacuum robotic arm, achieves micron-level three-dimensional alignment of the memory daughterboard and the main carrier substrate, effectively resolving misalignment issues caused by thermal expansion or mechanical deviation in traditional processes and ensuring precise alignment of the contact array. Spiral progressive coating combined with ultrasonic degassing technology achieves industry-leading uniformity in the distribution of nanosilver conductive adhesive, completely eliminating air bubble defects within the adhesive layer and laying the foundation for the formation of a three-dimensional conductive network.

[0024] In the embodiment of the present invention: S330: Daughterboard precise embedded control: The storage sub-board is grabbed by a vacuum robot arm, maintaining a pre-installation gap of 0.5-1mm with the main board; Activate the vision positioning system for 3D alignment calibration, identifying the fiducial markers (50μm diameter gold disks) in the grooves of the main substrate and matching them with the alignment crosshairs (10μm width) on the bottom surface of the daughter board. A two-stage embedding strategy is used. The first stage is coarse positioning at a speed of 0.1-0.3mm / s, and the second stage switches to micron-level precision at 0.02-0.05mm / s. S340: Vacuum lamination process control: Apply an initial contact pressure of 0.05-0.1MPa at the moment of contact; Start the gradient pressurization program: the pressure is linearly increased to 0.8 MPa in the first 30 seconds, and the pressure is maintained at 1 MPa for 90 seconds to complete the initial bonding; The infrared heaters were activated synchronously to maintain the substrate temperature at 45-55°C.

[0025] The two-stage embedding strategy uses dynamic speed control to quickly complete component pre-installation in the coarse positioning stage and then switch to the fine positioning mode, significantly reducing the impact of assembly stress on the precision structure.

[0026] The synergistic effect of a gradient pressurization process and infrared temperature control optimizes the rheological properties and curing morphology of the conductive adhesive, forming a dense, low-impedance interface connection layer. This solution not only significantly improves the production efficiency and yield of the lamination process, but also ensures stable electrical and mechanical performance of the device over long-term service through closed-loop control of process parameters throughout the entire process, providing highly consistent manufacturing assurance for the large-scale production of LPCAMM modules.

[0027] In the embodiment of the present invention: The step S400 specifically includes: S410: Equipped with a multi-axis dynamic pressure control system, including: Three independent piezoelectric ceramic drive units, pressure resolution ±0.05MPa; Distributed pressure sensor array (accuracy ±1%FS); Adaptive PID feedback control module; S420: Implementing a multimodal pressure loading strategy: Pre-pressing phase (0-30 seconds): 0.5-0.8 MPa baseline pressure is applied along the Z axis, and an oscillating pressure of ±0.2 MPa (frequency 5-10 Hz) is simultaneously activated along the XY axis. Infiltration phase (31-60 seconds): Increase the Z-axis pressure to 1.2-1.5 MPa and apply a rotational shear stress field (shear rate 20-50 s⁻¹); Forming stage (61-90 seconds): Apply 2MPa peak pressure and maintain for 30 seconds, and simultaneously trigger 50kHz micro-amplitude vibration (amplitude ≤5μm); This embodiment significantly improves the quality and stability of the three-dimensional conductive network formed by conductive adhesives through the integration of dynamic pressure fields and intelligent control technologies. By employing a multi-axis coordinated pressure loading strategy and closed-loop control using multimodal pressure loading and real-time resistance feedback, it overcomes the limitations of traditional single-direction pressure application, effectively eliminating the agglomeration and uneven distribution of conductive particles, and ensuring the high density and low impedance characteristics of the three-dimensional interconnected structure.

[0028] In the embodiment of the present invention: S430: Three-dimensional conductive network formation control: Adjust pressure parameters through real-time resistance monitoring feedback: When the unit area resistance value is greater than 10mΩ, the local pressure is automatically increased by 0.3MPa; When the standard deviation of the resistance value is ≥0.5mΩ, XY stress compensation is started, and an argon protective atmosphere (dew point ≤-40°C) is injected during the pressure holding stage. The pressure unloading adopts a two-step relaxation mode: the pressure is reduced to 0.8MPa at a rate of 0.1MPa / s in the first stage, and completely released at a rate of 0.05MPa / s in the second stage. S440: Conductive adhesive morphology optimization process: Control the directional alignment of silver nanoparticles: apply a 1-3T pulsed magnetic field (pulse width 10ms, interval 50ms), with the magnetic field direction forming a 45° angle with the pressure axis; Constructing vertical interconnected structures: Using pressure-temperature synergy (80-100°C) to cause silver particles to grow in chains along the Z axis; Surface topology optimization: Use mold imprinting to form micro-protrusion structures (height 20-40μm, density 150-200 / mm²).

[0029] The introduction of magnetic field-assisted orientation technology, combined with the synergistic effect of pressure and temperature, guides the orderly arrangement of conductive particles along a preset direction, significantly improving the continuity and current-carrying capacity of the longitudinal conductive path. The innovative design of the gradient pressure relief mechanism, through precise control of the pressure relaxation process, suppresses adhesive layer rebound and the generation of interface microcracks, ensuring the long-term mechanical stability of the connection interface. This solution not only achieves a significant improvement in the electrical performance of the conductive network, but also reduces reliance on operator experience through intelligent process control logic, significantly improving production consistency and yield, and providing core process assurance for the reliable operation of LPCAMM modules in high-frequency, high-load scenarios, while also shortening the manufacturing cycle and reducing energy costs.

[0030] In the embodiment of the present invention: The steps S500 and S600 include: S510: Gradient curing process control: Initial curing stage: Maintain the first temperature zone (80-90°C) for 20-30 minutes in an inert atmosphere to activate the initial cross-linking of the nanosilver conductive adhesive; stress release stage: step-by-step temperature increase to the second temperature zone (100-110°C) and apply periodic micro-vibration to eliminate interface residual stress; stabilization stage: cool down to the third temperature zone (60-70°C) to complete curing and form a reversible physically connected micrograin boundary structure; By controlling the curing cooling rate (1-2°C / min) and the holding time, the conductive adhesive layer retains 10-15% elastic deformation space, supporting non-destructive disassembly of the daughter board.

[0031] S520: Reversible interface structure design: Laser-process a micro-groove array on the surface of the cured conductive adhesive layer to form a mechanical interlocking interface; reserve a decoupling groove at the edge of the main substrate to achieve self-release of interface stress through the difference in thermal expansion coefficient.

[0032] S610: Thermally conductive dielectric composite medium injection process: modified silicone resin (thermal conductivity ≥3 W / m·K, dielectric strength ≥20 kV / mm); graded composite of flake boron nitride (diameter-to-thickness ratio 50:1) and spherical alumina (particle size 0.5-5μm); addition of thixotropic fumed silica to control the dynamic viscosity characteristics of the medium.

[0033] A capillary guide structure, including a microcolumn array and radial drainage grooves, is pre-installed in the gap between the daughter board and the main substrate. The medium is injected synchronously using a multi-point injection needle, and bubble-free filling is achieved with vacuum negative pressure (10⁻¹ Torr). The medium penetration front is dynamically monitored, and the injection speed and path are adjusted through pressure feedback.

[0034] S620: Modular package molding: Irradiate with 365nm wavelength for 10-15 seconds to form a temporary fixed structure; radiate heating from the center of the device to the outer edge (temperature difference ΔT = 20°C) to induce directional shrinkage of the dielectric; Laser-etched micro-anchor arrays (depth 20-50 μm) on the package surface, coated with an organic-inorganic hybrid coating to achieve IP67 protection and electromagnetic shielding (SE ≥ 40 dB) This embodiment successfully addresses the conflict between reversible connection and long-term reliability in LPCAMM modular packaging through the collaborative innovation of a gradient curing process and composite packaging technology. The gradient curing process's segmented temperature control strategy, combined with a dynamic stress release mechanism, ensures a stable mechanical connection between the conductive adhesive layer while retaining space for elastic deformation. This allows for non-destructive removal and reinstallation of the daughterboard without damaging the interface, significantly improving the module's maintainability. The formulation design of the thermally conductive dielectric composite and vacuum-assisted filling technology, through optimized gradation of functional fillers and controlled rheological properties, impart excellent heat dissipation and electrical insulation to the encapsulation layer, effectively preventing heat buildup and signal crosstalk issues in high-density integration. The modular packaging molding process, through the innovative combination of in-situ curing and interface strengthening, achieves a lightweight and compact package while building multiple protective barriers, significantly enhancing the device's impact resistance, moisture resistance, and electromagnetic shielding capabilities in complex environments. This solution overcomes the limitations of traditional packaging processes, balancing manufacturing efficiency and product lifespan, and provides a complete technical path that combines flexibility and high reliability for field upgrades, rapid repairs, and large-scale deployment of LPCAMM modules.

[0035] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be included therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

Claims

1. A method for manufacturing a reconfigurable LPCAMM memory device, characterized in that The following steps are involved: S100: preparing a main carrier substrate, forming stepped grooves on both sides of the substrate, and disposing array-type elastic contact terminals at the bottom of the stepped grooves; S200: A detachable storage daughter board is manufactured separately, wherein a self-compensating contact array corresponding to the main substrate is configured on the bottom surface of the daughter board, and a heat dissipation enhancement layer is provided on the top surface; S300: Pre-coat nano-silver conductive adhesive in the assembly groove, and use vacuum lamination equipment to accurately embed the storage sub-board into the main substrate; S400: The daughterboard is temporarily fixed by a mechanical slide rail locking mechanism, and a pressure of 0.5-2MPa is applied to form a three-dimensional conductive network with the conductive adhesive. S500: Gradient curing is performed at a low temperature of 80-120°C to form a reversible physical connection structure; S600: Inject a thermally conductive dielectric composite medium into the gap between the daughter board and the main substrate to complete the modular packaging.

2. The method for manufacturing a reconfigurable LPCAMM memory device according to claim 1, wherein: The step S100 specifically includes: S110: A modified epoxy resin substrate with a thermal expansion coefficient of ≤8 ppm / °C is selected as the main supporting substrate, wherein the substrate contains a glass fiber reinforcement material with a mass fraction of 15%-25%; S120: A CNC milling machine is used to machine stepped grooves with a depth difference of 0.15-0.35mm on both sides of the substrate. The first-level groove has a depth of 0.8-1.2mm and a sidewall inclination angle of 85°-88°. The second-level groove has a depth of 0.5-0.8mm and a laser-etched rough surface of 2-5μm on the sidewall. S130: Selective metallization is performed on the bottom of the stepped groove, forming a 50-80μm thick copper-nickel composite layer through mask sputtering. A micro-stamping process is used to form an array of elastic contact terminals. Each contact has an Ω-shaped arch structure with an arch height of 120-150μm. A 2-5μm nickel-gold composite layer is electroplated on the contact surface, with a surface roughness Ra ≤ 0.1μm. S140: Arrange an anti-overflow barrier structure in the transition area between the first-level groove and the second-level groove. The anti-overflow barrier structure includes a silicone barrier dam with a width of 0.1-0.3 mm set along the edge of the transition area between the first-level groove and the second-level groove, and an adsorption micropore array is distributed at intervals of 100-200 μm at the bottom of the stepped groove.

3. The method for manufacturing a reconfigurable LPCAMM memory device according to claim 2, wherein: The step S200 specifically includes: S210: Preparing a detachable storage daughterboard substrate: Aluminum silicon carbide composite material is used as the substrate with a thickness in the range of 0.6-0.9mm. The substrate surface is laser activated to form an array of micron-scale interconnected pits with a diameter of 80-120μm. 2-4 layers of staggered copper-molybdenum alloy conductive foil are laminated on the activated surface. S220: preparing a contact positioning window with a diameter of 150-250 μm on the bottom surface of the daughter board by photolithography; A nickel-cobalt alloy spring pin array was grown using a selective electrodeposition process.

4. The method for manufacturing a reconfigurable LPCAMM memory device according to claim 3, wherein: The step S200 further includes: S230: A three-dimensional heat dissipation microstructure with a depth of 0.2-0.4mm is laser-processed on the top surface of the daughterboard, with an array of staggered micropillars and interconnected radiation grooves. Growing a 5-10 μm aluminum nitride thermal conductive layer on the surface of the microstructure by chemical vapor deposition; The matrix material is an expanded graphite skeleton, and the phase change material is a molten salt eutectic mixture; A flexible graphene thermal pad with a thickness of 0.1-0.3 mm is mounted on the surface of the heat dissipation layer.

5. A method for manufacturing a reconfigurable LPCAMM memory device according to any one of claims 1 to 4, characterized in that: The step S300 specifically includes: S310: It uses a dual-station rotary vacuum chamber, maintains a working vacuum degree within the range of 10⁻² to 10⁻³ Torr, is equipped with an infrared radiation heating system, has a temperature control accuracy of ±1.5°C, and integrates a high-precision visual positioning system; S320: Use an automatic dispensing machine to perform spiral progressive coating along the stepped groove profile. The adhesive layer thickness is controlled at 80-120μm, with a width tolerance of ±5μm. Immediately after coating, 50-80kHz ultrasonic vibration is applied to eliminate bubble defects.

6. The method for manufacturing a reconfigurable LPCAMM memory device according to claim 5, wherein: The step S300 also includes S330: The storage daughter board is grabbed by a vacuum robot arm, and a pre-installed gap of 0.5-1mm is maintained with the main board. Activate the vision positioning system for 3D alignment calibration, identify the fiducial mark points in the groove of the main substrate, and match them with the alignment crosshairs on the bottom surface of the daughter board; A two-stage embedding strategy is used, with the first stage performing coarse positioning at a speed of 0.1-0.3 mm / s, and the second stage switching to micron-level refinement at 0.02-0.05 mm / s; S340: Apply an initial contact pressure of 0.05-0.1 MPa at the moment of contact; Start the gradient pressurization program: the pressure is linearly increased to 0.8 MPa in the first 30 seconds, and the pressure is maintained at 1 MPa for 90 seconds to complete the initial bonding; The infrared heaters were activated synchronously to maintain the substrate temperature at 45-55°C.

7. The method for manufacturing a reconfigurable LPCAMM memory device according to claim 6, wherein: The step S400 specifically includes: S410: Equipped with a multi-axis dynamic pressure control system, including: Three independent piezoelectric ceramic drive units, pressure resolution ±0.05MPa; distributed pressure sensor array; Adaptive PID feedback control module; S420: Pre-pressing stage (0-30 seconds): Apply 0.5-0.8 MPa reference pressure along the Z axis and simultaneously activate ±0.2 MPa oscillating pressure along the XY axis; Infiltration stage (31-60 seconds): Increase the Z-axis pressure to 1.2-1.5 MPa and apply a rotational shear stress field; Forming stage (61-90 seconds): Apply 2MPa peak pressure and maintain for 30 seconds, and simultaneously trigger 50kHz micro-vibration.

8. The method for manufacturing a reconfigurable LPCAMM memory device according to claim 7, wherein: The step S400 further includes: S430: Adjust pressure parameters through real-time resistance monitoring feedback: When the unit area resistance value is greater than 10mΩ, the local pressure is automatically increased by 0.3MPa; When the standard deviation of the resistance value is ≥0.5mΩ, XY stress compensation is started, and argon protective atmosphere is injected during the pressure holding stage. The pressure unloading adopts a two-step relaxation mode: the pressure is reduced to 0.8MPa at a rate of 0.1MPa / s in the first stage, and completely released at a rate of 0.05MPa / s in the second stage. S440: Controlling the directional alignment of silver nanoparticles: applying a 1-3T pulsed magnetic field with the magnetic field direction forming a 45° angle with the pressure axis; The silver particles grow in a chain along the Z axis through the synergistic effect of pressure and temperature; The micro-protrusion structure is formed by mold embossing.

9. The method for manufacturing a reconfigurable LPCAMM memory device according to claim 8, wherein: The steps S500 and S600 include: S510: Gradient curing process control: Maintaining the first temperature zone for 20-30 minutes in an inert atmosphere activates the initial cross-linking of the nanosilver conductive adhesive; stepwise increasing the temperature to the second temperature zone and applying periodic micro-vibration to eliminate the interface residual stress; cooling to the third temperature zone to complete the curing and form a reversible physically connected micro-grain boundary structure; By controlling the curing cooling rate and holding time, the conductive adhesive layer retains 10-15% elastic deformation space; S520: Reversible interface structure design: Laser-process a micro-groove array on the surface of the cured conductive adhesive layer to form a mechanical interlocking interface; reserve a decoupling groove at the edge of the main substrate; S610: Thermally conductive dielectric composite injection process: modified silicone resin; graded composite of flake boron nitride (diameter-to-thickness ratio 50:1) and spherical alumina; addition of thixotropic fumed silica; A capillary guide structure, including a micropillar array and radial drainage grooves, is pre-installed in the gap between the daughter board and the main substrate. A multi-point injection needle is used to synchronously inject the medium, and vacuum negative pressure is used to achieve bubble-free filling. The medium penetration front is dynamically monitored, and the injection speed and path are adjusted through pressure feedback. S620: Modular package molding: Irradiate with 365nm wavelength for 10-15 seconds to form a temporary fixed structure; radiate heat from the center of the device to the outer edge to induce directional shrinkage of the dielectric; A micro-anchor array is laser-etched on the outer surface of the package body and coated with an organic-inorganic hybrid coating to achieve IP67-level protection and electromagnetic shielding.

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