Solid-liquid mixed SMD chip and processing method thereof

Abstract

The invention belongs to the technical field of chips, and discloses a solid-liquid mixed SMD chip and a processing method thereof.The processing method comprises the steps that liquid functional units are sequentially packaged in a polymer composite film through the micro-fluidic technology, and a composite substrate structure with a semi-solid protective layer is formed; based on the physical characteristics of the composite substrate structure and the historical process data set, a dynamic mounting parameter set is generated through a parameter prediction model, the composite substrate structure is mounted to a target substrate through low-temperature welding flux, and a local welding temperature field is regulated and controlled synchronously according to the dynamic mounting parameter set; in the welding process, thermal stress data are collected in real time through a distributed sensor, a finite element simulation model is combined to drive an execution mechanism to dynamically compensate the deformation difference between the composite substrate structure and the substrate, then a cross-scale functional coating is sprayed on the surface, and mechanical matching and packaging stability of a solid-liquid interface are achieved through a graded curing technology. And the yield and the stability of the chip device are improved.

Description

Technical Field

[0001] The present invention relates to the field of chip technology, and particularly to a solid-liquid hybrid SMD chip and a processing method thereof. Background Art

[0002] As the core component of a new generation of high-frequency electronic devices, the solid-liquid hybrid SMD chip exhibits irreplaceable advantages in 5G communication base stations, millimeter-wave radars, and flexible electronic systems. Through the collaborative design of a rigid substrate and embedded liquid functional units (such as liquid metal, ionic gel), it combines high-frequency low-loss signal transmission and self-adaptive deformation capabilities, meeting the requirements of high-density integration in complex electromagnetic environments. With the miniaturization development of the Internet of Things and intelligent wearable devices, the application demand for such chips in fields such as micro antenna arrays and biosensing modules continues to grow, but the processing stability of their heterogeneous material interfaces has become a key technical bottleneck restricting mass production.

[0003] The existing chip mounting process for solid-liquid hybrid SMD chips mostly uses traditional reflow soldering technology. The specific process is as follows: After directly assembling the unencapsulated liquid unit with the rigid substrate, welding is completed at a peak temperature of 260°C using a high-temperature solder (such as Sn-Ag-Cu alloy, melting point > 220°C). However, the liquid functional unit is prone to phase change expansion or even vaporization in a high-temperature thermal field (such as the volume expansion rate of gallium-based alloys being > 15% above 200°C), resulting in cracking of the encapsulation structure or deterioration of electrical performance; at the same time, the interfacial stress concentration caused by the difference in thermal expansion coefficients of heterogeneous materials (such as ceramic substrate CTE ≈ 7 ppm / °C vs. liquid metal CTE ≈ 30 ppm / °C) will cause the warpage of the device after mounting to exceed the tolerance, severely reducing the consistency of high-frequency signal transmission.

[0004] The core defect of the existing technology lies in the contradiction between the high-temperature process and the thermal sensitivity of liquid materials, which directly leads to the technical dilemmas of insufficient processing yield and accelerated device life attenuation rate. Summary of the Invention

[0005] The purpose of the present invention is to provide a solid-liquid hybrid SMD chip and a processing method thereof to solve the above technical problems.

[0006] To achieve this purpose, the present invention adopts the following technical solutions: A processing method for a solid-liquid hybrid SMD chip, comprising the following steps: S1, encapsulating the liquid functional unit in a polymer composite film through microfluidics technology in sequence to form a composite substrate structure with a semi-solid protective layer; S2, generating a dynamic mounting parameter set through a parameter prediction model based on the physical properties and historical process data set of the composite substrate structure, the dynamic mounting parameter set including a temperature gradient, a stress compensation coefficient, and a mounting pressure range; S3. Mount the composite substrate structure onto the target substrate using a low-temperature solder, and simultaneously regulate the local welding temperature field according to the dynamic mounting parameter set, so that the temperature threshold in the region where the liquid functional unit is located is lower than its phase change critical value; S4. During the welding process, collect thermal stress data in real time through distributed sensors, and combine with the finite element simulation model to drive the actuator to dynamically compensate for the deformation difference between the composite substrate structure and the substrate; S5. Spray a cross-scale functional coating on the surface of the component after completing the deformation compensation, and achieve the mechanical matching and packaging stability of the solid-liquid interface through a hierarchical curing process.

[0007] Optionally, step S1 specifically includes: S11. Prepare a SiO 2 / PDMS composite film modified by a silane coupling agent as the substrate of the polymer composite film, and laser etch a microcavity structure on its surface that matches the volume of the target liquid functional unit; S12. After mixing the liquid metal functional unit with nano-scale heat-conducting particles, inject them into the microcavity structure in a pulse-width modulation mode through a microfluidic syringe to form a three-dimensionally constrained liquid unit preform; S13. Cover a second layer of SiO 2 / PDMS composite film on the surface of the liquid unit preform, and form a chemical bond at the interface of the double-layer composite film through plasma activation treatment to construct a fully enclosed microchannel structure.

[0008] Optionally, step S1 further includes: S14. Apply a gradient pressure to the encapsulated composite film and simultaneously perform ultraviolet light-induced cross-linking, so that the PDMS around the liquid unit undergoes a phase change to form a dense coating layer; S15. Use femtosecond laser to process an array of through-holes on the surface of the composite film, and form a metallized conductive channel on the inner wall of the through-holes through vapor deposition, and output a composite substrate structure with a semi-solid protective layer and an embedded liquid functional unit.

[0009] Optionally, step S2 specifically includes: S21. Construct a dataset including the physical properties of the thickness distribution, thermal conductivity gradient, and liquid unit volume ratio of the composite substrate structure, and perform feature correlation with the mounting offset and temperature response curve in the historical process dataset to obtain a fused feature vector; S22. Train a parameter prediction model based on the LSTM neural network architecture, input the fused feature vector, and output the initial predicted value of the dynamic mounting parameter set; S23. Iteratively correct the initial prediction values through a multi-objective optimization algorithm. The constraint conditions include the thermal exposure threshold of the liquid cell, the substrate deformation tolerance range, and the placement machine movement accuracy, and generate a dynamic placement parameter set including the temperature gradient, stress compensation coefficient, and placement pressure range.

[0010] Optionally, the specific steps of step S3 include: S31. Provide a Sn-Bi-Ag low-temperature solder alloy and process it into a particle-reinforced solder paste, and coat the solder paste on the pad area of the target substrate according to a preset array through micro-droplet jetting technology. S32. Based on the placement pressure range in the dynamic placement parameter set, use an SMD placement bracket to align the composite substrate structure with the target substrate, and at the same time load a pressure feedback module to calibrate the flatness of the contact surface in real time. S33. Activate the infrared array heater and divide the welding area into a liquid cell protection area and a solder joint melting area according to the temperature gradient data of the dynamic placement parameter set, and achieve thermal field isolation through multi-segment independent temperature control of the infrared array heater. S34. Start the welding program, apply a high-frequency thermal pulse in the solder joint melting area, and simultaneously actively dissipate heat through the micro thermoelectric cooler in the liquid cell protection area to maintain the temperature fluctuation range within ±3°C. S35. Use an infrared thermal imager to monitor the thermal distribution data of the composite substrate structure and the target substrate in real time, so as to obtain the interface fusion state, and dynamically adjust the heater power and the cooler air volume according to the thermal distribution data to form a closed-loop control of the welding process. S36. After welding, start the gradient cooling program, cool down in stages at a preset rate, and apply a constant negative pressure adsorption force in the liquid cell area.

[0011] Optionally, the SMD placement bracket includes: A bracket body, on which a plurality of positioning grooves for accommodating the composite substrate structure are provided. A driving component, which is used to drive the bracket body to adjust the position along the X / Y / Z three axes. Vacuum adsorption holes, which are connected to a vacuum component and are used to apply a constant negative pressure adsorption force to the liquid cell area.

[0012] Optionally, the specific steps of step S4 include: S41. Deploy a distributed sensing array circumferentially at the bonding interface between the composite substrate structure and the substrate, collect thermal stress data in real time, and collect thermal distribution data through an infrared thermal imager. S42. Input the real-time data stream into a thermo-mechanical coupled finite element simulation model, and iteratively calculate the dynamic evolution trend of the deformation difference based on the material constitutive equation of the composite substrate structure to generate a deformation compensation instruction set. S43. Drive the piezoelectric ceramic actuator array according to the deformation compensation instruction set, apply an asymmetric reverse stress to the edge of the composite substrate structure, synchronously adjust the adsorption force gradient of the vacuum adsorption holes, and achieve the first-order compensation of the deformation difference; S44. Scan the adjacent area of the liquid cell by ultraviolet laser selectively, stimulate the local phase change of the photosensitive nanoparticles, and dynamically adjust the equivalent elastic modulus of the composite substrate structure to complete the second-order adaptive compensation; S45. Regularly reconstruct the parameters of the finite element simulation model based on the real-time strain data of the compensated component, and iteratively optimize the weight coefficient of the compensation algorithm.

[0013] Optionally, the step S5 specifically includes the following steps: S51. Prepare a dielectric-thermal conductive functional coating slurry composed of nano-aluminum oxide particles and epoxy resin; S52. Use plasma spraying to clean the surface of the component after deformation compensation, and evenly cover the dielectric-thermal conductive functional coating slurry to the solid-liquid interface area by electrostatic atomization spraying in an inert gas environment to form a primary coating film with a preset thickness; S53. Apply a low-frequency alternating magnetic field to the primary coating film, induce the nano-aluminum oxide particles to be arranged in an orderly manner to form a vertical heat conduction path, and synchronously start the ultraviolet pre-curing program to realize the shaping of the coating skeleton.

[0014] Optionally, the step S5 further includes: S54. Perform a hierarchical thermal curing process: in the first stage, heat up to 80°C at a rate of 2°C / min and keep it constant for 30 min to complete the cross-linking of the resin matrix; in the second stage, heat up to 135°C at a rate of 5°C / min and apply an isotropic pressure of 0.8 MPa to promote the formation of a mechanical interlocking interface between the coating and the composite substrate structure; S55. Use a laser to process an array of micro-vias on the surface of the cured coating, and deposit a Ti / Cu composite metal layer on the inner wall of the vias by magnetron sputtering to construct a cross-scale conductive channel interconnected with the external circuit.

[0015] The present invention also provides a solid-liquid hybrid SMD chip, which adopts the above processing method of the solid-liquid hybrid SMD chip. The solid-liquid hybrid SMD chip specifically includes: A composite substrate structure formed by encapsulating a liquid functional unit with a polymer composite film; A low-temperature solder bonding layer that bonds the composite substrate structure to the target substrate using a Sn-Bi-Ag low-temperature solder alloy; A cross-scale functional coating, a dielectric-thermal conductive composite coating covering the surface of the component, and the composite coating is composed of nano-Al 2 O 3 particles and an epoxy resin matrix, and has a gradient pore distribution and a vertical heat conduction path; A conductive interconnect structure, an array of micro-vias formed on the surface of a functional coating by femtosecond laser processing.

[0016] Compared with the prior art, the present invention has the following beneficial effects: First, the microfluidic technology is used to encapsulate liquid functional units in a polymer composite film to form a composite substrate structure with a semi-solid protective layer; based on the physical properties of this structure and historical process data, a dynamic mounting parameter set including temperature gradient, stress compensation coefficient, and mounting pressure range is generated through a parameter prediction model to realize the dynamic optimization of mounting parameters and improve the alignment accuracy of the heterogeneous material interface; subsequently, the composite substrate structure is mounted on the target substrate using a low-temperature solder, and the local welding temperature field is regulated synchronously according to the dynamic parameter set to ensure that the temperature in the liquid unit area is always lower than its phase change critical value; during the welding process, thermal stress data is collected in real time by distributed sensors, and the deformation difference between the substrate and the substrate is dynamically compensated by combining a finite element simulation model to drive the actuator; finally, a cross-scale functional coating is sprayed on the surface of the component after deformation compensation, and the mechanical matching and packaging stability of the solid-liquid interface are realized through a hierarchical curing process to form a complete solid-liquid hybrid SMD device; this method solves the processing problem of solid-liquid hybrid SMD chips through low-temperature dynamic compensation and data-driven packaging optimization, and improves the yield and stability of chip devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0018] The structures, proportions, sizes, etc. shown in the drawings of this specification are only used to cooperate with the content disclosed in the specification for those familiar with this technology to understand and read, and are not used to limit the limited conditions for the implementation of the present invention. Therefore, they do not have technical substance. Any modification of the structure, change of the proportional relationship, or adjustment of the size, without affecting the effects that the present invention can produce and the purposes that can be achieved, should still fall within the scope that the technical content disclosed by the present invention can cover.

[0019] Figure 1 One of the flow diagrams of the processing method of the solid-liquid hybrid SMD chip in Embodiment 1; Figure 2 Another flow diagram of the processing method of the solid-liquid hybrid SMD chip in Embodiment 1; Figure 3 The top view structure diagram of the SMD patch bracket in Embodiment 2. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0020] In order to make the object, features, and advantages of the present invention more obvious and understandable, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the embodiments described below are only a part of the embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0021] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. It should be noted that when a component is considered to be "connected" to another component, it may be directly connected to the other component or there may be intermediate components present at the same time.

[0022] The technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and through specific embodiments.

[0023] Embodiment 1: Combined with Figures 1 to 2 As shown, the embodiment of the present invention provides a processing method for a solid-liquid hybrid SMD chip, including the following steps: S1, encapsulate the liquid functional unit in the polymer composite film in sequence through microfluidic technology to form a composite substrate structure with a semi-solid protective layer; effectively inhibit the evaporation and flow out of control of the liquid functional unit in the high-temperature process through the polymer composite film pre-encapsulation technology.

[0024] S2, based on the physical characteristics and historical process data set of the composite substrate structure, generate a dynamic mounting parameter set through a parameter prediction model. The dynamic mounting parameter set includes a temperature gradient, a stress compensation coefficient, and a mounting pressure range; realize the dynamic optimization of the mounting parameters by combining the data-driven characteristics of the parameter prediction model, and significantly improve the alignment accuracy of the heterogeneous material interface.

[0025] S3, mount the composite substrate structure on the target substrate using low-temperature solder, and synchronously control the local welding temperature field according to the dynamic mounting parameter set, so that the temperature threshold in the area where the liquid functional unit is located is lower than its phase change critical value; adopt the low-temperature solder and the local temperature field control strategy to reduce the thermal exposure of the liquid unit.

[0026] S4. During the welding process, thermal stress data is collected in real time by distributed sensors, and the deformation difference between the composite substrate structure and the substrate is dynamically compensated by combining the finite element simulation model to drive the actuator; at the same time, the distributed sensing and dynamic compensation mechanism can eliminate more than 90% of the thermal stress mismatch and avoid the risk of structural delamination.

[0027] S5. Spray a cross-scale functional coating on the surface of the component after deformation compensation is completed, and achieve the mechanical matching and packaging stability of the solid-liquid interface through a hierarchical curing process. The hierarchical curing process improves the shear strength of the solid-liquid interface through the gradient crosslinking of the cross-scale coating, and finally forms a packaging structure with both high-frequency performance and mechanical stability.

[0028] The working principle of the present invention is as follows: First, the liquid functional unit is encapsulated in the polymer composite film by microfluidic technology to form a composite substrate structure with a semi-solid protective layer; based on the physical characteristics of this structure and historical process data, a dynamic mounting parameter set including temperature gradient, stress compensation coefficient, and mounting pressure range is generated through a parameter prediction model to realize the dynamic optimization of mounting parameters and improve the alignment accuracy of the heterogeneous material interface; subsequently, the composite substrate structure is mounted on the target substrate using a low-temperature solder, and the local welding temperature field is regulated synchronously according to the dynamic parameter set to ensure that the temperature in the liquid unit area is always lower than its phase change critical value; during the welding process, thermal stress data is collected in real time by distributed sensors, and the deformation difference between the substrate and the substrate is dynamically compensated by combining the finite element simulation model to drive the actuator; finally, a cross-scale functional coating is sprayed on the surface of the component after deformation compensation is completed, and the mechanical matching and packaging stability of the solid-liquid interface are achieved through a hierarchical curing process to form a complete solid-liquid hybrid SMD device; this method solves the processing problem of the solid-liquid hybrid SMD chip through low-temperature dynamic compensation and data-driven packaging optimization, and improves the yield and stability of the chip device.

[0029] In this embodiment, specifically, step S1 specifically includes: S11. Prepare a SiO 2 / PDMS composite film modified by a silane coupling agent as the substrate of the polymer composite film, and laser etch a microcavity structure on its surface that matches the volume of the target liquid functional unit.

[0030] SiO 2 / PDMS composite film: It is composed of silica nanoparticles (SiO 2 ), and a poly(dimethylsiloxane) (PDMS) matrix. A silane coupling agent (such as KH-550) is used to enhance the interfacial bonding force between SiO 2 and PDMS to form a substrate material with both flexibility (elongation at break > 150%) and thermal stability (temperature resistance > 200 °C).

[0031] Laser-etched microcavity: Precision etching is carried out using ultraviolet laser. Through spot diameter control (≤20μm) and scanning path planning, a microcavity structure is formed.

[0032] S12, After mixing the liquid metal functional unit with nano-scale heat-conducting particles, it is injected into the microcavity structure through a microfluidic syringe in a pulse-width modulation mode to form a three-dimensionally constrained liquid unit preform. Liquid metal mixing: Gallium-based alloy (Ga-In-Sn, melting point 10°C) is mixed with aluminum nitride nanoparticles (AlN, particle size 50nm, proportion 5wt%) to improve the thermal conductivity of the liquid metal (thermal conductivity > 30W / mK).

[0033] Pulse-width modulation microfluidics: By controlling the opening and closing of the valve of the microfluidic syringe through high-frequency pulses (frequency 20Hz, pulse width 50ms), the filling of the liquid metal is achieved, avoiding the generation of bubbles.

[0034] S13, Cover the surface of the liquid unit preform with a second layer of SiO 2 / PDMS composite film. Through plasma activation treatment, chemical bonding is formed at the interface of the double-layer composite film to construct a fully enclosed microchannel structure. Plasma activation bonding: The surface of the composite film is bombarded with oxygen plasma to generate active hydroxyl groups (-OH), promoting the double-layer film to form chemical bonding through silicon-oxygen bonds (Si-O-Si), and the interfacial bonding strength > 1.5MPa.

[0035] Fully enclosed microchannel: A sealed cavity is formed through the bonding of the double-layer film, and the liquid unit is completely wrapped to avoid leakage or oxidation of the liquid metal in subsequent processes.

[0036] S14, Apply a gradient pressure to the encapsulated composite film and simultaneously conduct ultraviolet light-induced crosslinking to make the PDMS around the liquid unit undergo a phase change to form a dense coating layer. Gradient pressure encapsulation: Apply pressure in stages (0.5→3MPa, rate 0.2MPa / s) to promote the uniform distribution of the liquid metal and discharge the residual gas.

[0037] Ultraviolet light-induced crosslinking: Use 365nm ultraviolet light (irradiation dose 3000mJ / cm2) to excite the photoinitiator in PDMS (such as Darocur 1173) to initiate a crosslinking reaction, forming a semi-solid coating layer with a uniform thickness (±2μm), and the hardness is increased to Shore A 50.

[0038] S15, Use femtosecond laser to process arrayed through-holes on the surface of the composite film, and form a metallized conductive channel on the inner wall of the through-holes through vapor deposition to output a composite substrate structure with a semi-solid protective layer and an embedded liquid functional unit.

[0039] Gas-phase deposition metallization, depositing a titanium (Ti) adhesion layer (50 nm) and a copper (Cu) conductive layer (thickness 10 μm) on the inner wall of the through-hole by magnetron sputtering, achieving a through-hole resistance < 5 mΩ.

[0040] It should be noted that the above steps achieve high-precision control of the microcavity structure through microcavity precision forming and laser etching technology; liquid cell protection, the synergistic effect of plasma bonding and ultraviolet cross-linking forms an airtight package; femtosecond laser + gas-phase deposition process ensures the low-resistance interconnection characteristics of the through-hole; SiO 2 / PDMS composite film has both flexible packaging and thermal management capabilities, supporting the stability of the solid-liquid hybrid structure.

[0041] In this embodiment, specifically, step S2 specifically includes: S21, constructing a dataset containing the physical properties of the thickness distribution, thermal conductivity gradient, and liquid cell volume ratio of the composite substrate structure, and performing feature correlation with the mounting offset and temperature response curve in the historical process dataset to obtain a fused feature vector; By constructing a high-precision physical property dataset and performing feature correlation with historical process data, a fused feature vector is formed, providing a comprehensive and reliable data basis for subsequent parameter prediction and significantly improving the accuracy of the prediction model.

[0042] Physical property measurement specifically includes: Thickness distribution, measured by a white light interferometer with a resolution of 0.1 μm; Thermal conductivity gradient, measured by transient thermal reflectometry (TDTR) with an accuracy of ±0.1 W / mK, reflecting the spatial distribution of the thermal properties of the material; Liquid cell volume ratio, calculated based on the microcavity volume and the liquid metal injection amount to ensure data reliability.

[0043] Feature correlation and fusion, principal component analysis (PCA) dimensionality reduction: extracting key features and reducing data redundancy; Historical process data integration: correlating the mounting offset, temperature response curve with the physical properties to form a multi-dimensional fused feature vector.

[0044] S22, training a parameter prediction model based on the LSTM neural network architecture, inputting the fused feature vector, and outputting the initial predicted value of the dynamic mounting parameter set; using the LSTM neural network to train the fused feature vector to generate the initial predicted value of the dynamic mounting parameter, realizing the intelligent mapping from data to parameters and significantly improving the efficiency and accuracy of parameter prediction.

[0045] LSTM neural network architecture: input layer, fusing feature vectors (dimension 50); hidden layer, 3 layers of LSTM cells (128 neurons per layer), introducing Dropout (0.2) to prevent overfitting; output layer, initial predicted values of the dynamic mounting parameter set (temperature gradient, stress compensation coefficient, mounting pressure range).

[0046] S23, iteratively correcting the initial predicted values through a multi-objective optimization algorithm, with constraints including the thermal exposure threshold of the liquid cells, the substrate deformation tolerance range, and the placement machine movement accuracy, to generate a dynamic mounting parameter set including a temperature gradient (ΔT ≤ 15 °C / s), a stress compensation coefficient (asymmetric ratio of X / Y axes 1:1.2 - 1.8), and a mounting pressure range (0.5 - 1.2 N).

[0047] Iteratively correct the initial predicted values through a multi-objective optimization algorithm to generate a dynamic mounting parameter set that meets the constraints of the thermal exposure threshold of the liquid cells, the substrate deformation tolerance range, and the placement machine movement accuracy, ensuring the global optimality of the process parameters.

[0048] Multi-objective optimization algorithm: objective functions, thermal exposure threshold of the liquid cells (T < 160 °C), substrate deformation tolerance range (warpage < 20 μm), placement machine movement accuracy (±1 μm); Constraints: temperature gradient (ΔT ≤ 15 °C / s), stress compensation coefficient (asymmetric ratio of X / Y axes 1:1.2 - 1.8), mounting pressure range (0.5 - 1.2 N).

[0049] In this embodiment, specifically, step S3 specifically includes: S31, providing a Sn - Bi - Ag low - temperature solder alloy and processing it into a particle - reinforced solder paste, and coating the solder paste onto the pad area of the target substrate according to a preset array through micro - droplet jetting technology; By preparing a particle - reinforced low - temperature solder paste and coating it using micro - droplet jetting technology, the high strength and low thermal stress of the solder joints are ensured, while avoiding damage to the liquid cells caused by high temperatures.

[0050] S32, based on the mounting pressure range in the dynamic mounting parameter set, aligning the composite substrate structure with the target substrate using an SMD placement bracket, and simultaneously loading a pressure feedback module to calibrate the flatness of the contact surface in real - time; Based on the dynamic mounting parameter set, use a high - precision SMD placement bracket and a pressure feedback module to achieve sub - micron alignment of the composite substrate structure and the substrate, ensuring the placement accuracy and interface flatness.

[0051] S33. Activate the infrared array heater and divide the welding area into a liquid cell protection area (T < 160 °C) and a solder joint melting area (T = 145 ± 5 °C) according to the temperature gradient data in the dynamic mounting parameter set. Achieve thermal field isolation through multi-zone independent temperature control of the infrared array heater; Achieve thermal field isolation in the welding area through multi-zone independent temperature control of the infrared array heater, ensure that the temperature in the liquid cell protection area is lower than the phase change critical value, and at the same time, the solder joint area reaches the melting temperature.

[0052] The infrared array heater is divided into 8 zones; Thermal field isolation: The temperature difference between adjacent zones > 80 °C to ensure that the thermal exposure of the liquid cell < 0.5 s.

[0053] S34. Start the welding program, apply a high-frequency thermal pulse in the solder joint melting area, and simultaneously actively dissipate heat through the micro thermoelectric cooler in the liquid cell protection area to maintain the temperature fluctuation range within ±3 °C; Through the synergistic effect of high-frequency thermal pulse welding and active heat dissipation of the micro thermoelectric cooler, achieve rapid melting of the solder joint and temperature stability in the liquid cell area, and avoid thermal damage.

[0054] S35. Use an infrared thermal imager to continuously monitor the thermal distribution data of the composite substrate structure and the target substrate, thereby obtaining the interface fusion state, and dynamically adjust the heater power and cooler air speed according to the thermal distribution data to form a closed-loop control of the welding process; Continuously monitor the thermal distribution data through an infrared thermal imager, dynamically adjust the heater power and cooler air speed, and form a closed-loop control of the welding process to ensure the interface fusion quality and temperature uniformity.

[0055] S36. After welding, start the gradient cooling program, cool down in stages at a preset rate of 5 - 15 °C / min, and apply a constant negative pressure adsorption force in the liquid cell area to inhibit the release of residual thermal stress, avoid device warping and interface delamination, and ensure the long-term stability of the package structure.

[0056] In this embodiment, specifically, step S4 specifically includes: S41. Deploy a distributed sensing array circumferentially at the bonding interface between the composite substrate structure and the substrate to continuously collect thermal stress data, and collect thermal distribution data through an infrared thermal imager.

[0057] S42. Input the real-time data stream into a thermo-mechanical coupled finite element simulation model, and iteratively calculate the dynamic evolution trend of the deformation difference based on the material constitutive equation of the composite substrate structure to generate a deformation compensation instruction set; It should be noted that the thermal-mechanical coupling finite element simulation model is an embedding rate-related plastic model (strain rate correction coefficient η = 0.8), which can accurately describe the mechanical behavior of the composite substrate structure; its iterative calculation is based on real-time data flow to dynamically update the model parameters and predict the evolution trend of deformation difference (error < 3μm).

[0058] Deformation compensation instruction set: includes displacement instructions of piezoelectric ceramic brakes, gradient adjustment values of vacuum adsorption force, etc.; instruction update frequency: 1Hz to ensure real-time compensation.

[0059] S43, drive the piezoelectric ceramic brake array according to the deformation compensation instruction set, apply asymmetric reverse stress at the edge of the composite substrate structure, and synchronously adjust the adsorption force gradient of the vacuum adsorption holes to achieve first-order compensation of the deformation difference; Drive the piezoelectric ceramic brake array according to the deformation compensation instruction set, apply asymmetric reverse stress at the edge of the composite substrate structure, and at the same time adjust the adsorption force gradient of the vacuum adsorption holes to achieve first-order compensation of the deformation difference, significantly reducing the interfacial stress concentration.

[0060] Vacuum adsorption force gradient adjustment, adsorption force range: 0.1 - 0.8N; the gradient distribution is dynamically adjusted according to the interfacial stress distribution to ensure uniform stress on the contact surface.

[0061] S44, by selectively scanning the adjacent area of the liquid cell with ultraviolet laser, excite the local phase change of photosensitive nanoparticles (TiO 2 -SiO 2 core-shell structure), dynamically adjust the equivalent elastic modulus of the composite substrate structure, complete second-order adaptive compensation, and further improve the deformation correction accuracy.

[0062] Phase change of photosensitive nanoparticles, TiO 2 -SiO 2 The core-shell structure undergoes local phase change after being excited by ultraviolet light, and the dynamic adjustment range of the elastic modulus is: 1 - 5GPa.

[0063] S45, regularly reconstruct the parameters of the finite element simulation model based on the real-time strain data of the compensated component, and iteratively optimize the weight coefficient of the compensation algorithm.

[0064] Based on the real-time strain data of the compensated component, regularly reconstruct the parameters of the finite element simulation model, and iteratively optimize the weight coefficient of the compensation algorithm to ensure the continuous optimization and adaptive ability of the compensation process.

[0065] Real-time strain data: collected by a distributed sensing array, used to update the parameters of the material constitutive equation; the reconstruction frequency is, for example, once every 5 minutes to ensure the accuracy of the model.

[0066] In this embodiment, specifically, step S5 specifically includes: S51. Prepare a dielectric-thermal conductive functional coating slurry composed of nano-aluminum oxide particles and epoxy resin. Among them, the particle size of the nano-aluminum oxide particles is 20 nm to ensure uniform dispersion; the addition ratio is 30 wt% to optimize the thermal conductivity; the epoxy resin matrix selects a low-viscosity epoxy resin (viscosity 500 - 1000 cP) for easy subsequent spraying; preferably, a photoinitiator is added for ultraviolet pre-curing.

[0067] By preparing a functional coating slurry composed of nano-aluminum oxide particles and epoxy resin, it provides a material basis with both high thermal conductivity and dielectric insulation for subsequent coating spraying, ensuring the high-frequency performance and thermal management ability of the device.

[0068] S52. Use plasma spray cleaning to finish the surface of the deformed component, and in an inert gas environment, uniformly cover the dielectric-thermal conductive functional coating slurry to the solid-liquid interface area through electrostatic atomization spraying to form a primary coating film with a preset thickness. Remove the surface contaminants of the component through plasma cleaning, and in an inert gas environment, use electrostatic atomization spraying technology to uniformly cover the functional coating slurry to form a primary coating film with uniform thickness, ensuring good bonding between the coating and the substrate.

[0069] S53. Apply a low-frequency alternating magnetic field to the primary coating film to induce the directional arrangement of nano-aluminum oxide particles to form a vertical heat conduction path, and simultaneously start the ultraviolet pre-curing program to realize the shaping of the coating skeleton. Induce the directional arrangement of nano-aluminum oxide particles through a low-frequency alternating magnetic field to form a vertical heat conduction path, and at the same time, ultraviolet pre-curing realizes the shaping of the coating skeleton, significantly improving the thermal conductivity and mechanical strength of the coating.

[0070] S54. Execute a hierarchical thermal curing process: in the first stage, heat up to 80 °C at a rate of 2 °C / min and keep it constant for 30 min to complete the cross-linking of the resin matrix; in the second stage, heat up to 135 °C at a rate of 5 °C / min and apply an isotropic pressure of 0.8 MPa to promote the formation of a mechanical interlocking interface between the coating and the composite substrate structure, significantly improving the mechanical properties and interface bonding strength of the packaging structure.

[0071] S55. Use a laser to process an array of micro-vias on the surface of the cured coating, and deposit a Ti / Cu composite metal layer on the inner wall of the vias through magnetron sputtering to construct a cross-scale conductive channel interconnected with the external circuit.

[0072] Construct a cross-scale conductive channel interconnected with the external circuit by laser processing an array of micro-vias and combining magnetron sputtering technology to deposit a Ti / Cu composite metal layer, ensuring the high-frequency signal transmission performance of the device.

[0073] Femtosecond laser for laser processing of micro vias (pulse width 150 fs), via diameter 20 μm, aspect ratio 5:1, ensuring processing accuracy; heat affected zone: <1 μm, avoiding coating damage.

[0074] The deposition material for magnetron sputtering metallization is a Ti / Cu composite layer (Ti adhesion layer 50 nm, Cu conductive layer 10 μm); via resistance <10 mΩ, ensuring low-resistance interconnection.

[0075] Example 2: Combined Figure 3 As shown, in this embodiment, the present invention also provides an SMD patch bracket, which is used to support the mounting work of the composite substrate structure target substrate. The SMD patch bracket includes: The bracket body 10 is provided with a plurality of positioning grooves 11 for accommodating the composite substrate structure.

[0076] The driving component 20 is used to drive the bracket body to adjust its position along the X / Y / Z three axes.

[0077] The vacuum adsorption holes 30 are connected to a vacuum component and are used to apply a constant negative pressure adsorption force to the liquid unit area.

[0078] Example 3: The present invention also provides a solid-liquid hybrid SMD chip, which adopts the processing method of the solid-liquid hybrid SMD chip as in Example 1. The solid-liquid hybrid SMD chip specifically includes: The composite substrate structure is formed by encapsulating a liquid functional unit with a polymer composite film; the polymer composite film includes a SiO 2 / PDMS composite film, the liquid functional unit is a gallium-based alloy or an ion gel, and the composite substrate structure has a semi-solid protective layer and an embedded microcavity structure.

[0079] The low-temperature solder joint layer uses a Sn-Bi-Ag low-temperature solder alloy to join the composite substrate structure to the target substrate; the solder joint layer contains nano-Al 2 O 3 particle reinforcement phase, and a mechanical interlock structure is formed at the solder joint interface.

[0080] The cross-scale functional coating is a dielectric-thermal conductive composite coating covering the surface of the component. The composite coating is composed of nano-Al 2 O 3 particles and an epoxy resin matrix, and has a gradient pore distribution and a vertical heat conduction path.

[0081] The conductive interconnection structure is an array of micro vias formed on the surface of the functional coating by femtosecond laser processing; a Ti / Cu composite metal layer is deposited on the inner wall of the micro vias to achieve low-resistance interconnection between the solid-liquid hybrid SMD chip and the external circuit.

[0082] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for processing a solid-liquid hybrid SMD chip, characterized in that: The steps include: S1, encapsulating the liquid functional units in the polymer composite film in turn by microfluidic technology to form a composite substrate structure with a semi-solid protective layer; S2, based on the physical properties of the composite substrate structure and the historical process data set, generating a dynamic mounting parameter set through a parameter prediction model, wherein the dynamic mounting parameter set includes a temperature gradient, a stress compensation coefficient, and a mounting pressure range; S3, using low-temperature solder to mount the composite base structure to the target substrate, and simultaneously regulating the local soldering temperature field according to the dynamic mounting parameter set, so that the temperature threshold of the area where the liquid functional unit is located is lower than its phase change critical value; S4, during the welding process, the thermal stress data is collected in real time through distributed sensors, and the actuator is driven to dynamically compensate for the deformation difference between the composite base structure and the base plate in combination with the finite element simulation model; S5, spraying a cross-scale functional coating on the surface of the component that has completed deformation compensation, and achieving mechanical matching and packaging stability of the solid-liquid interface through a graded curing process.

2. The processing method of the solid-liquid hybrid SMD chip according to claim 1, characterized in that: The step S1 specifically includes: S11, preparing a SiO2 / PDMS composite membrane modified by a silane coupling agent as a polymer composite membrane substrate, and laser etching the surface thereof to form a microcavity structure matching the volume of a target liquid functional unit; S12, mixing the liquid metal functional unit with the nanoscale thermal conductive particles, and injecting the mixture into the microcavity structure in a pulse width modulation mode through a microfluidic syringe to form a three-dimensional constrained liquid unit preform; S13, covering the surface of the liquid unit preform with a second layer of SiO2 / PDMS composite film, and forming chemical bonds at the interface of the double-layer composite film through plasma activation treatment to construct a fully enclosed microchannel structure.

3. The processing method of the solid-liquid hybrid SMD chip according to claim 2, characterized in that: The step S1 further comprises: S14, applying gradient pressure to the encapsulated composite film and simultaneously performing ultraviolet light-induced cross-linking to cause the PDMS at the periphery of the liquid unit to undergo a phase change to form a dense coating layer; S15, uses femtosecond laser to process arrayed through holes on the surface of the composite film, and forms metallized conductive channels on the inner walls of the through holes by vapor deposition, outputting a composite substrate structure with a semi-solid protective layer and embedded liquid functional units.

4. The processing method of the solid-liquid hybrid SMD chip according to claim 1, characterized in that: The step S2 specifically includes: S21, constructing a data set of physical properties including thickness distribution, thermal conductivity gradient and liquid unit volume ratio of the composite substrate structure, and performing feature correlation with the mounting offset and temperature response curve in the historical process data set to obtain a fused feature vector; S22, training a parameter prediction model based on an LSTM neural network architecture, inputting the fused feature vector, and outputting an initial prediction value of a dynamic placement parameter set; S23, iteratively correct the initial prediction value through a multi-objective optimization algorithm. The constraints include the liquid unit thermal exposure threshold, substrate deformation tolerance range and placement machine motion accuracy, and generate a dynamic placement parameter set including temperature gradient, stress compensation coefficient and placement pressure range.

5. The processing method of the solid-liquid hybrid SMD chip according to claim 1, characterized in that: The step S3 specifically includes: S31, providing Sn-Bi-Ag low temperature solder alloy and processing it into a particle enhanced solder paste, and applying the solder paste to a pad area of ​​a target substrate in a preset array by a droplet jetting technology; S32, based on the placement pressure range in the dynamic placement parameter set, using an SMD patch bracket to align the composite base structure with the target substrate, and loading a pressure feedback module to calibrate the flatness of the contact surface in real time; S33, activating the infrared array heater and dividing the welding area into a liquid unit protection area and a solder point melting area according to the temperature gradient data of the dynamic mounting parameter set, and realizing thermal field isolation through multi-segment independent temperature control of the infrared array heater; S34, start the welding procedure, apply high-frequency heat pulses to the molten zone of the solder joint, and simultaneously actively dissipate heat through the micro-thermoelectric cooling sheet in the liquid unit protection zone to maintain the temperature fluctuation range within ±3°C; S35, using an infrared thermal imager to monitor the thermal distribution data of the composite base structure and the target substrate in real time, thereby obtaining the interface fusion state, and dynamically adjusting the heater power and the cooling plate wind speed according to the thermal distribution data to form a closed-loop control welding process; S36, after welding is completed, a gradient cooling program is started, the temperature is reduced in stages at a preset rate, and a constant negative pressure adsorption force is applied to the liquid unit area.

6. The method for processing a solid-liquid hybrid SMD chip according to claim 5, characterized in that: The SMD patch bracket includes: A bracket body, wherein the bracket body is provided with a plurality of positioning grooves for accommodating the composite substrate structure; A driving assembly, the driving assembly is used to drive the support body to adjust the position along the X / Y / Z three axes; The vacuum adsorption hole is connected to a vacuum component and is used to apply a constant negative pressure adsorption force to the liquid unit area.

7. The method for processing a solid-liquid hybrid SMD chip according to claim 6, characterized in that: The step S4 specifically includes: S41, deploying a distributed sensor array circumferentially at the bonding interface between the composite base structure and the substrate to collect thermal stress data in real time, and collecting thermal distribution data through an infrared thermal imager; S42, inputting the real-time data stream into the finite element simulation model of thermal-mechanical coupling, iteratively calculating the dynamic evolution trend of deformation difference based on the material constitutive equation of the composite substrate structure, and generating a deformation compensation instruction set; S43, driving the piezoelectric ceramic brake array according to the deformation compensation instruction set, applying an asymmetric reverse stress to the edge of the composite substrate structure, and synchronously adjusting the adsorption force gradient of the vacuum adsorption hole to achieve first-order compensation of the deformation difference; S44, by selectively scanning the adjacent area of ​​the liquid unit with an ultraviolet laser, the local phase change of the photosensitive nanoparticles is stimulated, the equivalent elastic modulus of the composite substrate structure is dynamically adjusted, and the second-order adaptive compensation is completed; S45, regularly reconstructing the parameters of the finite element simulation model based on the real-time strain data of the compensated component, and iteratively optimizing the weight coefficient of the compensation algorithm.

8. The method for processing a solid-liquid hybrid SMD chip according to claim 5, characterized in that: The step S5 specifically includes the following steps: S51, preparing a dielectric-thermal conductive functional coating slurry composed of nano-alumina particles and epoxy resin; S52, using plasma jet cleaning to complete the deformation compensation component surface, and in an inert gas environment, using electrostatic atomization spraying to evenly cover the dielectric-thermal conductive functional coating slurry to the solid-liquid interface area to form an initial coating film with a preset thickness; S53, applying a low-frequency alternating magnetic field to the primary coating film to induce the nano-aluminum oxide particles to be oriented to form a vertical heat conduction path, and simultaneously starting the ultraviolet pre-curing program to achieve coating skeleton shaping.

9. The method for processing a solid-liquid hybrid SMD chip according to claim 8, characterized in that: The step S5 further comprises: S54, performing a graded thermal curing process: in the first stage, the temperature is raised to 80°C at 2°C / min and kept at this temperature for 30 minutes to complete the crosslinking of the resin matrix, and in the second stage, the temperature is raised to 135°C at 5°C / min and an isotropic pressure of 0.8 MPa is applied to promote the formation of a mechanical interlocking interface between the coating and the composite substrate structure; S55 uses laser to process arrayed micro-through holes on the surface of the cured coating, and deposits a Ti / Cu composite metal layer on the inner wall of the through hole by magnetron sputtering to construct a cross-scale conductive channel interconnected with the external circuit.

10. A solid-liquid hybrid SMD chip, characterized in that: The processing method of the solid-liquid hybrid SMD chip according to any one of claims 1 to 9 is adopted, wherein the solid-liquid hybrid SMD chip specifically comprises: A composite substrate structure is formed by encapsulating a liquid functional unit with a polymer composite film; A low temperature solder bonding layer, using Sn-Bi-Ag low temperature solder alloy to bond the composite base structure to the target substrate; Cross-scale functional coating, a dielectric-thermal conductive composite coating covering the surface of the component, the composite coating is composed of nano-Al2O3 particles and epoxy resin matrix, with gradient pore distribution and vertical thermal conductive path; Conductive interconnect structure, arrayed micro-through holes formed on the surface of the functional coating by femtosecond laser processing.

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