Full-automatic high-precision flux spraying and hot-press bonding integrated device and method

Abstract

This invention relates to the field of semiconductor technology, specifically to a fully automated, high-precision flux spraying and thermocompression bonding integrated equipment and method. It includes a main control system, a substrate processing module, a high-precision flux spraying module, a chip processing module, a thermocompression bonding module, an integrated online detection module, an atmosphere control system, several multi-view vision alignment modules, and a transmission mechanism. The main control system integrates an industrial computer, a programmable logic controller, a motion control card, and an image processing unit to coordinate the timing actions of other modules, process sensor data, execute process formulas, store full-process data, and enable human-machine interaction. The substrate processing module includes a substrate loading unit, a substrate unloading unit, and a substrate preheating station to complete substrate loading, unloading, and preheating. Compared with existing technologies, it features high integration, improved efficiency, fully automated operation, guaranteed consistency, online monitoring, closed-loop process, data traceability, facilitated analysis, controllable environment, and stable quality.

Description

Technical Field

[0001] This invention relates to the field of semiconductor technology, specifically to a fully automated, high-precision flux spraying and hot-press bonding integrated equipment and method. Background Technology

[0002] The continuation of Moore's Law increasingly relies on advanced packaging technologies. Among these, thermocompression bonding technology has become a key process for high-end chip packaging due to its ability to achieve high-density, high-reliability, and high-precision interconnects. In this process, applying a uniform, controllable thickness layer of flux to the pads or bumps on the substrate is a prerequisite for ensuring bonding quality. This flux layer plays a role in removing oxide layers from the metal surface, promoting diffusion and reaction, providing temporary adhesion to fix the chip, and to some extent, inhibiting the formation of solder voids.

[0003] Currently, the mainstream production process is a typical discrete, multi-step model, such as... Figure 1 As shown, the following bottlenecks severely restrict industrial development: 1. Discrete processes and low efficiency. Flux coating and hot-press bonding, using methods such as spraying, screen printing, or lamination, are two completely separate processes in terms of physical space, equipment, and timing. The coated substrates must be manually or via an AMHS (Advanced Material Handling System) to the bonding equipment, involving multiple loading / unloading, alignment, and waiting processes. This results in low overall equipment efficiency (OEE), long production cycle time, limited capacity, and an inability to meet the high throughput demands of large-scale mass production.

[0004] 2. High levels of manual intervention and poor process consistency. Coating process: Especially in small-batch or R&D stages, semi-automatic or manual spraying is often used. Film thickness uniformity and coverage area accuracy are highly dependent on operator skill, leading to significant batch-to-batch variations. While screen printing offers some improvement, issues remain regarding screen cleaning, wear and tear, and adaptability to warped substrates. Loading and alignment processes: Substrate and chip loading and pre-alignment are largely done manually, introducing placement deviations, tilting, and contamination risks from electrostatic discharge (ESD), fingerprints, and particles. These factors directly narrow the hot-press bonding process window, resulting in large dispersion in key parameters such as interconnect resistance and shear strength after bonding, making it difficult to consistently improve product yield.

[0005] 3. High Risk of Process Exposure, Contamination, and Oxidation. The substrate coated with flux is completely exposed to the cleanroom environment air during transport, waiting, and loading to the bonding equipment. During this period: (a) volatile solvents in the flux may partially evaporate, altering its rheological properties (viscosity, thixotropy) and affecting the flow behavior during bonding; (b) airborne particulate matter (AMC) and particles in the environment may settle on the coating layer, becoming a source of bonding voids or conductive residues; (c) secondary oxidation may occur on the metal surfaces of the pads or bumps (such as Cu, SnAg, CuNiAu, etc.), weakening the flux's deoxidizing ability and increasing the risk of poor soldering. These uncontrollable intermediate process variables are significant contributing factors to bonding defects such as voids, incomplete fusion, and high resistance.

[0006] 4. Fragmented process data, making traceability and analysis difficult. Coating and bonding are performed on different equipment, and their process parameters and quality inspection data (such as spraying pressure / speed, film thickness measurement, bonding temperature / pressure / position curves, and alignment accuracy) are stored independently, forming "data silos." When failures occur in the final test or reliability assessment, it is difficult to effectively correlate the failure mode with the microscopic state of the front-end coating, making root cause analysis (RCA) cumbersome and inefficient, and lacking data-closed-loop support for process optimization.

[0007] 5. High resource consumption and cost. The discrete layout requires independent coating rooms, bonding rooms, and transit buffer areas, occupying a large amount of high-level cleanroom space. At the same time, each process step requires operation and maintenance personnel, and the low degree of automation leads to high labor costs, and the process stability is challenged by personnel turnover.

[0008] In summary, the existing technology architecture has become a key obstacle restricting the mass production capability, yield improvement, and cost control of advanced packaging. The industry urgently needs a revolutionary solution that can break down process barriers, achieve integrated, automated "coating-inspection-bonding," and enable continuous operation in a controlled environment. Summary of the Invention

[0009] To overcome the shortcomings of the prior art, this invention provides a fully automated, high-precision flux spraying and hot-press bonding integrated equipment and method.

[0010] To achieve the above objectives, a fully automated, high-precision flux spraying and hot-press bonding integrated equipment was designed, including a main control system, a substrate processing module, a high-precision flux spraying module, a chip processing module, a hot-press bonding module, an integrated online detection module, an atmosphere control system, several multi-field vision alignment modules, and a transmission mechanism. The main control system integrates an industrial computer, a programmable logic controller, a motion control card, and an image processing unit. It is used to coordinate the timing actions of other modules, process sensor data, execute process recipes, store data throughout the entire process, and enable human-machine interaction. The substrate processing module includes a substrate loading unit, a substrate unloading unit, and a substrate preheating station, which are used to complete the loading, unloading, and preheating of the substrate. Chip processing module: includes wafer loading unit, wafer alignment and expansion unit, and chip pick-up unit. The wafer loading unit is used to load the wafer frame; the wafer alignment and expansion unit is used to realize wafer angle correction and thin film expansion; the chip pick-up unit picks up the chip from the expanded wafer film and passes it to the transfer mechanism or places it directly on the substrate waiting to be bonded. High-precision flux spraying module: includes a spraying controller, several independently controllable micro-nozzles, and a film thickness controller. The spraying controller is electrically connected to the main control system, receives graphic data from the main control system, and controls the opening and closing of each micro-nozzle at a specific position and the droplet spraying frequency and volume. The hot-press bonding module includes a bonding head, a heating stage, a pressure control system, and a morphology measurement unit. The bonding head integrates a heater, a pressure control system, and a vacuum adsorption or mechanical clamping device for adsorbing and transferring the chip. The heating stage is used to support and heat the substrate and has multi-zone independent temperature control function. The pressure control system uses a servo motor or piezoelectric driver to integrate a high-sensitivity force sensor to achieve precise closed-loop control of the bonding pressure. Multi-field vision alignment module: includes several sets of high-resolution cameras and multi-angle light sources, which are respectively deployed at the processing positions of substrate alignment before spraying, pre-alignment after chip picking, and fine alignment before final bonding. Integrated online inspection module: includes a coating quality inspection unit, a bonding process monitoring unit, and a post-bonding initial inspection unit. The coating quality inspection unit is located after the coating station. It uses a 2D vision or 3D confocal microscope to detect the coverage integrity and positional accuracy of the coating pattern online, as well as the flux film thickness and volume distribution obtained through 3D morphology reconstruction. The data is fed back to the main control system in real time. The bonding process monitoring unit is integrated into the bonding head or heating table to collect and record the temperature curve, pressure curve, and table position of each bonding point in real time. The initial inspection unit after bonding is equipped with an optical microscope or an ultrasonic scanning microscope probe to perform a preliminary visual inspection of the bonded chip, or to sample and quickly screen for voids. Transmission mechanism: responsible for transmitting the substrate and chips between modules; Atmosphere control system: Construct one or more closed or semi-closed process environment protection chambers around the spraying area of ​​the high-precision flux spraying module, the flow path of the substrate after spraying, and the bonding chamber of the hot-press bonding module.

[0011] The substrate preheating station is located in front of the spraying station of the high-precision flux spraying module and has precise temperature control function.

[0012] The atmosphere control system includes a gas source, a gas purification unit, a flow and pressure control unit, an oxygen content and dew point analyzer, and an exhaust device. It continuously introduces and maintains an inert gas atmosphere into the environmental protection chamber, and controls the oxygen content and humidity in the environmental protection chamber to meet the requirements.

[0013] The hot-press bonding module also includes a morphology measurement unit, which uses a white light interferometer or a laser displacement sensor to quickly scan the coplanarity of the chip bumps and substrate pads before bonding, providing data for the adaptive bonding process.

[0014] To achieve the above objectives, a method for designing a fully automated, high-precision integrated equipment for flux spraying and hot-press bonding is provided, comprising the following steps: S1, System Preparation and Loading: Equipment initialization, atmosphere control system is started, oxygen content and humidity in the process environmental protection chamber are reduced to the set threshold; the operator places the material box loaded with the substrate to be processed into the substrate loading unit, and places the wafer frame loaded with the chip into the chip loading unit. S2, Substrate preheating and pre-coating alignment: The substrate enters the substrate preheating stage through the transfer mechanism and is preheated to the set temperature. After preheating, the robot transfers the substrate to the support platform below the high-precision flux spraying module. The multi-view vision alignment module identifies and positions the global alignment marks on the substrate and corrects the positional deviation of the substrate in the X, Y, and θ directions. S3, High-precision patterned flux spraying: The main control system drives the nozzle to scan above the aligned substrate according to the substrate design file, and controls the micro nozzle to spray flux droplets according to the predetermined pattern, forming a uniform flux coating with controllable thickness on the pad or bump area. S4, Online spraying quality inspection: After spraying is completed, the substrate is moved to the bottom of the spraying quality inspection unit. The spraying quality inspection unit quickly scans the sprayed area, generates a film thickness distribution map, and compares it with the standard process window. If the inspection result is qualified, it will proceed to the next process and be sent to the heating stage of the hot pressing bonding module. If it is unqualified, an alarm will be triggered and the substrate will be marked. S5, Chip Pickup and Pre-alignment: Simultaneously with step S2, the chip processing module is started, the wafer alignment and expansion unit completes the wafer angle correction and thin film expansion, the chip pickup unit picks up the designated chip according to the planned pickup sequence, and after pickup, the multi-field vision alignment module identifies the marks on the chip to complete the chip pre-alignment. S6, Precision alignment and bonding of substrate and chip: The chip is moved to the bonding head, and the multi-field vision alignment module simultaneously identifies high-precision local alignment marks on the substrate and chip, and performs sub-micron level precision alignment calculations; the bonding head carries the chip down according to the alignment results, and applies preset temperature, pressure and time curves in a protective atmosphere to complete the thermo-press bonding. S7, Post-bonding processing and unloading: After bonding is completed, the heating stage is cooled to a safe temperature, the bonding head releases the chip and lifts it up, and the bonded substrate is transferred to the post-bonding inspection unit for visual inspection through the transfer mechanism, and then transferred to the unloading unit.

[0015] It also includes step S8, data archiving and association: the main control system associates, packages and stores the data generated in steps S1 to S7 into the database according to the unique serial number, forming a complete and traceable process data package.

[0016] In step S8, the data includes substrate ID, preheating temperature, spraying pattern parameters, online detection film thickness distribution data, alignment accuracy data, temperature-pressure-position curve of the bonding process, and initial inspection image after bonding.

[0017] Compared with the prior art, the present invention has the following advantages: 1. High integration and improved efficiency: The spraying, pretreatment, bonding and testing processes are integrated into one machine, eliminating material handling and waiting time between processes, greatly shortening the production cycle, significantly improving the overall utilization rate of the equipment, and reducing the floor space required.

[0018] 2. Fully automated operation ensures consistency: From substrate loading to finished product unloading, the entire process requires no manual intervention, completely eliminating the risks of variation and contamination caused by human operation. Process parameters are precisely controlled by the program, ensuring a high degree of consistency within and between product batches.

[0019] 3. Online monitoring and closed-loop process: Integrated online film thickness measurement and bonding process monitoring enable real-time adjustment of process parameters, achieving a leap from open-loop production to closed-loop intelligent control, and improving process window and process capability.

[0020] 4. Data traceability facilitates analysis: End-to-end data binding and storage provides a complete data chain for product quality traceability and root cause analysis, accelerating the process debugging of new products and the resolution of mass production issues.

[0021] 5. Controllable environment and stable quality: The entire process is completed in a closed, controlled chamber, avoiding environmental exposure in intermediate steps, reducing the risks of solvent evaporation, particulate contamination and surface oxidation, and ensuring the quality of the bonding interface. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the prior art before the improvement of this invention.

[0023] Figure 2 This is a schematic diagram of the overall layout of the present invention.

[0024] Figure 3 This is a schematic diagram of the high-precision flux spraying module of the present invention.

[0025] Figure 4 This is a schematic diagram of the thermo-press bonding module in this invention.

[0026] Figure 5 This is a flowchart illustrating Embodiment 1 of the present invention. Detailed Implementation

[0027] The present invention will now be further described with reference to the accompanying drawings.

[0028] like Figures 2 to 4 As shown, the fully automated high-precision flux spraying and hot-press bonding integrated equipment in this embodiment includes a main control system, a substrate processing module, a high-precision flux spraying module, a chip processing module, a hot-press bonding module, an integrated online detection module, an atmosphere control system, several multi-field vision alignment modules, and a transmission mechanism. The main control system 1 integrates an industrial computer, a programmable logic controller, a motion control card, and an image processing unit. It is used to coordinate the timing actions of other modules, process sensor data, execute process recipes, store data throughout the entire process, and realize human-machine interaction. The substrate processing module includes a substrate loading unit 2, a substrate unloading unit 3, and a substrate preheating station 4, which are used to complete the loading, unloading, and preheating of the substrate. Chip processing module 5 includes a wafer loading unit, a wafer alignment and expansion unit, and a chip picking unit. The wafer loading unit is used to load the wafer frame; the wafer alignment and expansion unit is used to realize the wafer angle correction and thin film expansion; the chip picking unit uses a high-precision, force-controlled picking head to pick up the chip from the expanded wafer film and transfer it to the transfer mechanism or place it directly on the substrate 20 waiting to be bonded. A high-precision flux spraying module includes a spraying controller 7, several independently controllable micro-nozzles 8, and a film thickness controller 9. The spraying controller 7 is electrically connected to the main control system 1, receives graphic data from the main control system 1, and controls the opening and closing of each micro-nozzle 8 at a specific position, as well as the droplet spraying frequency and volume. This differs from traditional spraying core units. The high-precision flux spraying module of this invention employs non-contact, on-demand spraying technology, including piezoelectric inkjet and pneumatic jetting. It can precisely coat only the pads / bumps requiring soldering, achieving patterned and accurate coating, avoiding contamination of non-soldering areas, and saving flux material. Digital programming of film thickness is achieved by controlling the number and grayscale of droplets per unit area, resulting in precise and controllable film thickness with excellent uniformity. It can handle pads of different sizes, different spacings, and even warped substrates without requiring the replacement of stencils or masks.

[0029] The hot-press bonding module 10 includes a bonding head 11, a heating stage 12, a pressure control system 13, and a morphology measurement unit 14. The bonding head 11 integrates a heater 15, a pressure control system 13, and a vacuum adsorption or mechanical clamping device 6 for adsorbing and transferring the chip. It can apply precise vertical pressure and torque during the bonding process. The heating stage 12 is used to support and heat the substrate and has multi-zone independent temperature control to compensate for thermal non-uniformity caused by substrate warping. The pressure control system 13 uses a servo motor or piezoelectric driver to integrate a high-sensitivity force sensor to achieve precise closed-loop control of the bonding pressure. It can program complex pressure curves, such as step loading, holding pressure, and unloading. Multi-field vision alignment module: includes several sets of high-resolution cameras and multi-angle light sources such as coaxial light and ring light, which are deployed at the processing positions of substrate alignment before spraying, pre-alignment after chip picking, and fine alignment before final bonding. By recognizing the alignment marks on the substrate and chip through images, the module calculates their position and angle deviations and feeds the compensation amount back to the motion system in real time to ensure accurate spraying pattern position and chip bonding accuracy at the submicron level. Integrated online inspection module: including coating quality inspection unit 16, bonding process monitoring unit, and post-bonding initial inspection unit 17. The spraying quality inspection unit 16 is located behind the spraying station. It uses a 2D vision or 3D confocal microscope to detect the coverage integrity and positional accuracy of the sprayed pattern, as well as the flux film thickness and volume distribution obtained through 3D morphology reconstruction. The data is fed back to the main control system in real time. The bonding process monitoring unit is integrated into the bonding head or heating table, and collects and records the temperature curve, pressure curve, and worktable position of each bonding point in real time, reflecting the change of the protrusion collapse height over time, forming a unique "bonding fingerprint". The bonding pre-inspection unit 17 is equipped with a probe of an optical microscope or an ultrasonic scanning microscope to perform a preliminary appearance inspection on the bonded chip, such as position, tilt, or to sample for rapid screening of voids. Transfer Mechanism 18: A high-precision linear motor-driven transfer mechanism is used to transfer substrates and chips between modules. For example, the process involves: picking up the substrate from the substrate loading unit to the preheating station -> moving it to the spraying station after preheating -> moving it to the bonding station after spraying -> unloading the substrate after bonding. The entire process requires no manual intervention, and the transfer path is in a controlled environment or involves rapid transitions, minimizing exposure.

[0030] Atmosphere control system: One or more closed or semi-closed process environment protection cavities are constructed around the spraying area of ​​the high-precision flux spraying module, the flow path of the substrate 20 after spraying, and the bonding chamber of the hot-press bonding module 10.

[0031] The substrate preheating station 4 is located in front of the spraying station of the high-precision flux spraying module. It has a precise temperature control function, such as adjusting the temperature from room temperature to 200°C. The preheated substrate can optimize the wettability and leveling of the flux, obtain a more uniform film layer, and preheat the substrate to remove trace amounts of moisture that may be adsorbed.

[0032] The atmosphere control system includes a gas source, a gas purification unit, a flow and pressure control unit, an oxygen content and dew point analyzer, and an exhaust device. It continuously introduces and maintains an inert gas atmosphere into the environmental protection chamber, controlling the oxygen content and humidity within the chamber to meet requirements. In specific use, the oxygen content and humidity are controlled at extremely low levels, such as oxygen content O2 < 100 ppm and dew point < -40℃, effectively preventing flux volatilization, denaturation, and solder pad bump oxidation.

[0033] The hot-press bonding module 10 also includes a morphology measurement unit 14, which uses a white light interferometer or a laser displacement sensor to quickly scan the coplanarity of the chip bumps and substrate pads before bonding, providing data for the adaptive bonding process.

[0034] The method of the above-mentioned fully automatic high-precision flux spraying and hot-press bonding integrated equipment includes the following steps: S1, System preparation and loading: Equipment initialization, atmosphere control system is started, oxygen content and humidity in the process environmental protection chamber are reduced to the set threshold; the operator places the material box 19 loaded with the substrate to be processed 20 into the substrate loading unit 2, and places the wafer frame loaded with the chip 21 into the chip loading unit. S2, Substrate preheating and pre-coating alignment: Substrate 20 enters substrate preheating stage 4 through the transfer mechanism and is preheated to the set temperature. After preheating, the robot transfers substrate 20 to the support stage below the high-precision flux spraying module. The multi-view vision alignment module identifies and positions the global alignment marks on substrate 20 and corrects the positional deviation of substrate 20 in the X, Y, and θ directions. S3, High-precision patterned flux spraying: The main control system drives the nozzle to scan above the aligned substrate 20 according to the substrate design file, and controls the micro nozzle 8 to spray flux droplets according to the predetermined pattern, forming a uniform flux coating with controllable thickness in the pad or bump area. The spraying process is carried out under inert gas protection. S4, Online spraying quality inspection: After spraying is completed, the substrate 20 is moved to the area below the spraying quality inspection unit 16. The spraying quality inspection unit 16 quickly scans the sprayed area, generates a film thickness distribution map, and compares it with the standard process window. If the inspection result is qualified, it enters the next process and is sent to the heating stage 12 of the hot pressing bonding module. If it is unqualified, such as local thickness exceeding the tolerance or pattern missing, an alarm is triggered according to the preset strategy, and the substrate 20 is marked. In specific use, a local re-spraying unit can be added at the next station of the spraying quality inspection unit 16. The substrate 20 that has completed local re-spraying can re-enter the spraying quality inspection unit 16 for monitoring. S5, Chip Pickup and Pre-alignment: Simultaneously with step S2, the chip processing module 5 is started, the wafer alignment and expansion unit completes the wafer angle correction and thin film expansion, and the chip pickup unit picks up the designated chip 21 according to the planned pickup sequence. After pickup, the multi-field vision alignment module identifies the marks on the chip 21 to complete the pre-alignment of the chip 21. S6, precise alignment and bonding of substrate and chip: chip 21 is moved onto bonding head 11, and the multi-field vision alignment module simultaneously identifies high-precision local alignment marks on substrate 20 and chip 21, and performs sub-micron level precise alignment calculation; according to the alignment result, bonding head 11 carries chip 21 down, and in a precisely controlled protective atmosphere environment, a preset temperature, pressure and time curve is applied to complete thermo-press bonding; S7, Post-bonding processing and unloading: After bonding is completed, the heating stage 12 is cooled to a safe temperature, the bonding head 11 releases the chip 21 and lifts it up, and the bonded substrate is transferred to the post-bonding inspection unit 17 for visual inspection through the transfer mechanism, and then transferred to the unloading unit 3.

[0035] It also includes step S8, data archiving and association: the main control system associates, packages and stores the data generated in steps S1 to S7 into the database according to the unique serial number, forming a complete and traceable process data package.

[0036] In step S8, the data includes substrate ID, preheating temperature, spraying pattern parameters, online detection film thickness distribution data, alignment accuracy data, temperature-pressure-position curve of the bonding process, and initial inspection image after bonding.

[0037] Steps S2 to S4 process the substrate, and step S5 processes the chip, all simultaneously. Example

[0038] This embodiment uses the example of packaging a chiplet onto an organic substrate for illustration.

[0039] like Figure 2 As shown, the overall layout adopts a linear material flow design, and the transfer of substrate and chip is realized through the transfer mechanism.

[0040] Atmosphere control: Transparent acrylic covers are provided above the spraying module at position B, the spraying detection position at position C, the substrate transfer paths at positions D-1 to D-10, and the hot-pressing bonding chamber at position E, forming partially sealed sub-cavities. These are connected to the atmosphere control system through pipes to maintain a nitrogen atmosphere with O2 < 50 ppm and dew point < -60°C.

[0041] Substrate processing: The temperature control range of the substrate preheating station is room temperature to 180°C, with an accuracy of ±1°C. The preheating temperature is set to 80°C to optimize flux wetting.

[0042] Flux spraying: such as Figure 3 As shown, a piezoelectric on-demand spray nozzle with 1024 nozzles and a minimum droplet volume of 3 pL is used. The flux supply system has constant temperature (25°C) and degassing functions. The spray pattern is generated based on the substrate's Gerber file, and spraying is only performed on areas with copper pads. The dimensions are 80 μm x 80 μm with a spacing of 130 μm, and the target wet film thickness after spraying is 15 μm ± 1 μm.

[0043] Online inspection: The coating quality inspection unit uses a white light confocal sensor to quickly scan the printing area at a speed of <30 seconds per substrate, generate a thickness distribution color map, and calculate the average thickness, standard deviation, and uniformity index.

[0044] Chip processing: The chip pickup unit uses a force-controlled adsorption head with adjustable pickup force to prevent damage to the chip's micro-bumps.

[0045] Hot-press bonding: such as Figure 4 As shown, the bonding module heating stage has a maximum temperature of 400°C and a temperature control accuracy of ±1°C. The bonding head has a maximum pressure of 200 kgf and a pressure control accuracy of ±0.2 kgf. A built-in linear encoder monitors the bonding head displacement in real time, reflecting the protrusion collapse height. The process curve for this embodiment is as follows: heat to 250°C, apply a pressure of 5 kgf, hold for 5 seconds, then increase the pressure to 25 kgf, hold for 10 seconds, and finally separate after cooling to 150°C under pressure.

[0046] Main control system: Runs integrated control software, calls up process recipes, and displays the status of each module, sensor readings, and test results in real time.

[0047] like Figure 5 As shown, the specific process is as follows: S1: The operator places the 13 substrates with microbumps already implanted into the loading port and loads the 12-inch wafer containing the 13 Chiplet wafers onto the chip processing module.

[0048] S2: The ejection mechanism ejects a substrate to the substrate preheating stage and preheats it at 80°C for 60 seconds.

[0049] S3: After preheating, the substrate is sent to the spraying position. After visual alignment, the micro-nozzle, under nitrogen protection, completes the flux spraying according to the predetermined pattern, which takes about 45 seconds.

[0050] S4: The substrate is moved to the detection position, the confocal sensor scans, and the data confirms that the film thickness is 15.2μm and the uniformity is >95%, which is considered qualified.

[0051] S5: The chip processing module picks up a chipplet from the wafer and completes pre-alignment.

[0052] S6: The qualified substrate is fed into the heating stage of the thermosetting bonding module, and the chip is transferred to the bonding head. The chamber is purged with nitrogen. The vision system performs precise alignment of the substrate and chip, with a control accuracy of <0.5μm. The preset bonding process curve is executed, and the entire process takes about 60 seconds, with the pressure-displacement curve recorded in real time.

[0053] S7: After bonding is completed and cooled, the bonding head places the bonded component on the transfer mechanism and transfers it to the top camera for quick photo inspection to check the chip position. If there are no abnormalities, it is then transferred to the unloading station.

[0054] S8: All data of this substrate, ID: Sub_001, are stored together, including the coating thickness distribution map, alignment offset, bonding temperature-pressure-displacement curve, and post-bonding appearance image.

[0055] This invention deeply integrates flux precision coating technology with thermoforming bonding technology, achieving fully automated, intelligent, and environmentally friendly advanced packaging equipment and methods. It is particularly suitable for packaging processes of high-performance CPUs, GPUs, FPGAs, AI chips, high-bandwidth memory, and high-end devices based on Chiplet heterogeneous integration that employ Die-to-Substrate or Die-to-Wafer technologies.

Claims

1. A fully automatic, high-precision integrated equipment for flux spraying and hot-press bonding, characterized in that: It includes a main control system, a substrate processing module, a high-precision flux spraying module, a chip processing module, a hot-press bonding module, an integrated online detection module, an atmosphere control system, several multi-field vision alignment modules, and a transmission mechanism. The main control system (1) integrates an industrial computer, a programmable logic controller, a motion control card, and an image processing unit to coordinate the timing actions of other modules, process sensor data, execute process recipes, store full-process data, and realize human-machine interaction. The substrate processing module includes a substrate loading unit (2), a unloading unit (3), and a substrate preheating station (4), which are used to complete the loading, unloading, and preheating of the substrate. Chip processing module (5): includes a wafer loading unit, a wafer alignment and expansion unit, and a chip picking unit. The wafer loading unit is used to load the wafer frame; the wafer alignment and expansion unit is used to realize the wafer angle correction and thin film expansion; the chip picking unit picks up the chip from the expanded wafer film and passes it to the transfer mechanism or places it directly on the substrate (20) waiting to be bonded. High-precision flux spraying module: includes a spraying controller (7), several independently controllable micro nozzles (8), and a film thickness controller (9). The spraying controller (7) is electrically connected to the main control system (1), receives graphic data from the main control system (1), and controls the opening and closing of each micro nozzle (8) at a specific position and the droplet spraying frequency and volume. Hot-press bonding module (10): includes bonding head (11), heating stage (12), pressure control system (13) and morphology measurement unit (14). The bonding head (11) integrates heater (15), pressure control system (13) and vacuum adsorption or mechanical clamping device (6) for adsorbing and transferring the chip; the heating stage (12) is used to support and heat the substrate and has multi-zone independent temperature control function; the pressure control system (13) adopts a servo motor or piezoelectric driver to integrate a high-sensitivity force sensor to realize precise closed-loop control of bonding pressure; Multi-field vision alignment module: includes several sets of high-resolution cameras and multi-angle light sources, which are respectively deployed at the processing positions of substrate alignment before spraying, pre-alignment after chip picking, and fine alignment before final bonding. Integrated online inspection module: including spraying quality inspection unit (16), bonding process monitoring unit, and post-bonding initial inspection unit (17). The spraying quality inspection unit (16) is located behind the spraying station. It uses a 2D vision or 3D confocal microscope to detect the coverage integrity, position accuracy, and flux film thickness and volume distribution obtained by 3D morphology reconstruction of the sprayed pattern online. The data is fed back to the main control system in real time. The bonding process monitoring unit is integrated into the bonding head or heating table to collect and record the temperature curve, pressure curve, and table position of each bonding point in real time. The bonding pre-inspection unit (17) is equipped with an optical microscope or an ultrasonic scanning microscope probe to perform a preliminary appearance inspection on the bonded chip, or to sample and quickly screen for voids. Transmission mechanism (18): responsible for transmitting substrates and chips between modules; Atmosphere control system: One or more closed or semi-closed process environment protection cavities are constructed around the spraying area of ​​the high-precision flux spraying module, the flow path of the sprayed substrate (20), and the bonding chamber of the hot-press bonding module (10).

2. The fully automatic high-precision flux spraying and hot-press bonding integrated equipment according to claim 1, characterized in that: The substrate preheating station (4) is located in front of the spraying station of the high-precision flux spraying module and has precise temperature control function.

3. The fully automatic high-precision flux spraying and hot-press bonding integrated equipment according to claim 1, characterized in that: The atmosphere control system includes a gas source, a gas purification unit, a flow and pressure control unit, an oxygen content and dew point analyzer, and an exhaust device. It continuously introduces and maintains an inert gas atmosphere into the environmental protection chamber, and controls the oxygen content and humidity in the environmental protection chamber to meet the requirements.

4. The fully automatic high-precision flux spraying and hot-press bonding integrated equipment according to claim 1, characterized in that: The hot-press bonding module (10) also includes a morphology measurement unit (14), which uses a white light interferometer or a laser displacement sensor to quickly scan the coplanarity of the chip bumps and substrate pads before bonding, providing data for the adaptive bonding process.

5. A method for a fully automatic high-precision flux spraying and hot-press bonding integrated equipment according to any one of claims 1-4, characterized in that: Includes the following steps: S1, System preparation and loading: Equipment initialization, atmosphere control system is started, oxygen content and humidity in the process environmental protection chamber are reduced to the set threshold; the operator places the material box (19) loaded with the substrate to be processed (20) into the substrate loading unit (2), and places the wafer frame loaded with the chip (21) into the chip loading unit. S2, substrate preheating and pre-coating alignment: The substrate (20) enters the substrate preheating station (4) through the transfer mechanism and is preheated to the set temperature. After preheating, the robot transfers the substrate (20) to the support platform below the high-precision flux spraying module. The multi-view vision alignment module identifies and positions the global alignment mark on the substrate (20) and corrects the position deviation of the substrate (20) in the X, Y, and θ directions. S3, High-precision patterned flux spraying: The main control system drives the nozzle to scan above the aligned substrate (20) according to the substrate design file, and controls the micro nozzle (8) to spray flux droplets according to the predetermined pattern to form a uniform flux coating with controllable thickness in the pad or bump area. S4, Online inspection of coating quality: After the coating is completed, the substrate (20) is moved to the bottom of the coating quality inspection unit (16). The coating quality inspection unit (16) quickly scans the coating area, generates a film thickness distribution map, and compares it with the standard process window. If the inspection result is qualified, it will enter the next process and be sent to the heating stage (12) of the hot pressing bonding module. If it is unqualified, an alarm will be triggered and the substrate (20) will be marked. S5, Chip Pickup and Pre-alignment: Simultaneously with step S2, the chip processing module (5) is started, the wafer alignment and expansion unit completes the wafer angle correction and thin film expansion, the chip pickup unit picks up the designated chip (21) according to the planned pickup order, and after pickup, the multi-field vision alignment module identifies the marks on the chip (21) to complete the pre-alignment of the chip (21); S6, precise alignment and bonding of substrate and chip: chip (21) is moved onto bonding head (11), and multi-field vision alignment module simultaneously identifies high-precision local alignment marks on substrate (20) and chip (21) and performs sub-micron level precise alignment calculation; according to the alignment result, bonding head (11) carries chip (21) down and applies preset temperature, pressure and time curves in a protective atmosphere to complete hot-press bonding; S7, Post-bonding processing and unloading: After bonding is completed, the heating stage (12) is cooled to a safe temperature, the bonding head (11) releases the chip (21) and lifts it up. The bonded substrate is transferred to the post-bonding inspection unit (17) through the transfer mechanism for visual inspection, and then transferred to the unloading unit (3).

6. The method of the fully automatic high-precision flux spraying and hot-press bonding integrated equipment according to claim 5, characterized in that: It also includes step S8, data archiving and association: the main control system associates, packages and stores the data generated in steps S1 to S7 into the database according to the unique serial number, forming a complete and traceable process data package.

7. The method of the fully automatic high-precision flux spraying and hot-press bonding integrated equipment according to claim 6, characterized in that: In step S8, the data includes substrate ID, preheating temperature, spraying pattern parameters, online detection film thickness distribution data, alignment accuracy data, temperature-pressure-position curve of the bonding process, and initial inspection image after bonding.

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