A streaming audio chip vacuum welding device and an oxidation prevention method

Abstract

The present application relates to a kind of streaming media audio chip vacuum welding device and anti-oxidation method, device includes mainframe, vacuum cavity module, atmosphere control module, laser module, drive control module, image detection module and component detection module.Image and component detection module are integrated in precision welding head, positioning and topography quality inspection before and after welding are realized by micro camera, and the multiple gas components of pre-coated flux heated volatilization are detected in real time using Fourier transform infrared spectrometer;Real-time welding temperature is calculated by analyzing the proportion relationship of different gas components, and laser power is closed-loop controlled accordingly, so as to accurately and stably weld heat input.The present application realizes high-quality, non-oxidized precision welding by welding in vacuum environment, cooling in inert atmosphere, and combining the above multi-modal perception and closed-loop control, significantly improves the welding yield and long-term reliability of streaming media audio chip.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of laser welding of audio devices, in particular to a streaming audio chip vacuum welding device and an anti-oxidation method. BACKGROUND

[0002] With the popularization of streaming technology and high-fidelity audio, the performance requirements for audio processing chips are increasingly demanding. Precise components such as flat panel units inside such chips are extremely sensitive to circuit noise. During the chip packaging process, traditional reflow soldering and other welding methods, especially for WiFi modules and other chips with high power consumption and strong electromagnetic interference, are prone to cause micro voids in the welding points due to uneven thermal stress, insufficient flux evaporation, and other reasons. These voids not only affect the mechanical strength and thermal conductivity of the electrical connection, but also become the main source of circuit noise during long-term use, seriously degrading sound quality.

[0003] Laser welding, as a high-precision local heating technology, is introduced to solve the above problems. It has concentrated energy and small heat-affected zone, which can effectively reduce thermal stress. However, the existing laser welding scheme still has several limitations: first, if the welding process is carried out in air, oxidation is still likely to occur in the welding points and surrounding areas, affecting the connection reliability; second, the laser power is usually set to a fixed value or based on a simple process curve, which cannot adapt to small material differences, solder paste thickness fluctuations, or laser power drift, resulting in unstable welding temperature, sometimes too high causing spatter or device damage, and sometimes too low forming cold or false welding; third, the monitoring of welding quality is mostly post-detection, lacking direct and real-time sensing and feedback means for the welding state (especially temperature) during the process, and cannot intervene when defects occur.

[0004] Therefore, there is an urgent need in the art for a welding scheme that integrates process monitoring, real-time feedback, and active quality control, which can achieve precise closed-loop control of welding temperature in an oxygen-free environment, thereby fundamentally eliminating welding voids and oxidation, and ensuring the welding quality and long-term stability of streaming audio chips. SUMMARY

[0005] To solve the above problems, the present application provides a streaming audio chip vacuum welding device, which comprises a main frame, a vacuum cavity module, an atmosphere control module, a laser module, a drive control module, an image detection module and a composition detection module.

[0006] The vacuum cavity module comprises a cavity upper cover that can move up and down and a cavity tray that can slide horizontally, the cavity tray is used to move between the loading station and the sealed welding station, and is pressed together with the cavity upper cover to form a sealed welding chamber.

[0007] The atmosphere control module is in communication with the welding chamber for vacuumizing and filling with protective gas;

[0008] The laser module comprises a laser and a precision welding head; the image detection module and the composition detection module are integrated in the precision welding head;

[0009] The driving control module comprises a three-dimensional adjusting frame mounted on the cavity upper cover for moving the precision welding head;

[0010] The image detection module comprises a microscopic camera for visual positioning and alignment calibration of the chip pin and the circuit board pad before welding and for topographic image acquisition of the completed welding point after welding to analyze the welding quality.

[0011] The composition detection module is used for detecting a plurality of gas components volatilized from the pre-coated flux on the chip pin during the laser welding process in real time.

[0012] The composition detection module is in control connection with the laser module, which inversely calculates the current welding temperature according to the volatilization quality proportion relationship of the plurality of gas components and controls the laser power in real time according to the current welding temperature.

[0013] Further, the cavity tray is mounted on the main frame through a precision linear guide pair and is driven by a servo motor to reciprocate between the loading station and the sealed welding station through a ball screw; the cavity upper cover is driven by a servo cylinder to move up and down, and the stroke speed is adjustable at 5-50 mm / s; the lower edge of the cavity upper cover is embedded with a fluororubber sealing ring with a circular cross section, and when the cavity upper cover is pressed to be folded with the cavity tray, the sealing ring is compressed to realize dynamic sealing of the welding chamber and ensure the sealing of the chamber.

[0014] Further, the composition detection module is a Fourier transform infrared spectrometer, which covers a spectral range of to with a spectral resolution not less than ; the spectrometer is connected with the optical detection light path integrated in the precision welding head through a mid-infrared calcium fluoride optical fiber to realize in-situ real-time spectral acquisition of the volatile gas in the welding area, and the relative concentration of the plurality of gas components is quantified by analyzing the intensity of the absorption peak of different characteristic functional groups.

[0015] Further, the flux at least comprises a first volatile component and a second volatile component, the first volatile component has a lower boiling point than the second volatile component; the component detection module is configured to: calculate the ratio of the first gas component and the second gas component in real time; establish a mapping relationship model between the ratio and the welding temperature; when the ratio calculated in real time is lower than the corresponding value of the preset temperature interval, it is determined that the welding temperature is too low, and the laser power is controlled to be increased; when the ratio calculated in real time is higher than the corresponding value of the preset temperature interval, it is determined that the welding temperature is too high, and the laser power is controlled to be reduced.

[0016] Further, the first volatile component is malonic acid, and the second volatile component is sebacic acid; the Fourier transform infrared spectrometer is configured to monitor and calculate the ratio of the specific absorption peak intensities of different functional groups of the two acids to reverse the welding temperature.

[0017] The spectrometer monitors the absorption peak intensity of the C-O stretching vibration and the O-H in-plane bending vibration of the malonic acid molecule near The absorption peak intensity of the methylene bending vibration of the sebacic acid molecule near The absorption peak intensity of And real-time calculation of the intensity ratio Through the preset temperature-ratio calibration curve, the ratio Control the ratio In the range of 0.5 to 2.0, so as to stabilize the real-time temperature of the welding area in the ideal interval of 280℃±15℃.

[0018] Further, the precision welding head is a multifunctional integrated welding head, which has the following integrated inside the shell: the laser output fiber collimator of the laser module and the f-theta focusing lens group with a focal length of 100mm, which are used to output and focus the laser beam with a wavelength of 1080nm; the microscopic camera of the image detection module, whose optical axis is offset by an angle of 22° from the laser beam path through a beam splitter, ensuring that the coincidence error between the field center and the laser focal point on the workpiece surface is less than 25µm; the detection light path of the component detection module includes a pair of zinc selenide lenses transmitting in the mid-infrared waveband, which are used as excitation lenses and collection lenses respectively, and their optical axes are perpendicular to the laser beam and intersect at the laser focal point; a beam of excitation light from a mid-infrared broadband light source is conducted through a calcium fluoride fiber, irradiates the welding point area through the excitation lens, and the reflected signal light is received by the collection lens and conducted to the Fourier transform infrared spectrometer through another calcium fluoride fiber; the laser focal point, the camera field center and the infrared detection spot converge in the target detection area on the workpiece surface; the spatial position error of the centers of the three is less than 50µm.

[0019] Further, the application provides a streaming media audio chip welding anti-oxidation method using the device, characterized by comprising the following steps:

[0020] S1: loading and chamber sealing: in the loading station, the streaming media audio chip pre-coated with solder containing multiple volatile components is placed on the cavity tray, and then the cavity tray is driven to move horizontally to the sealed welding station; the upper cavity cover is pressed to form a sealed welding chamber with the cavity tray;

[0021] S2: vacuum pumping to establish a welding environment: start the atmosphere control module to pump the inside of the welding chamber to a pressure below 5 Pa;

[0022] S3: laser welding and multi-component feedback temperature control: in a vacuum environment, the control module drives the precision welding head to move according to the positioning data obtained by the image detection module in advance; the laser is started to weld the chip pins, while the component detection module monitors the concentration of multiple gas components in real time, calculates their proportion, and based on the mapping model of the proportion and the welding temperature, dynamically adjusts the laser power to control the welding temperature in the target interval;

[0023] S4: post-welding atmosphere protection and cooling: after all the laser welding is completed, the welding chamber is filled with protective gas to normal pressure, so that the welding points cool to room temperature in the protective atmosphere;

[0024] S5: unloading and quality analysis: open the cavity, move the cavity tray back to the loading station, take out the workpiece, and generate a welding quality report based on the recorded images and component data during the welding process.

[0025] Further, in step S3, the component detection module monitors the characteristic signal intensity ratio R2 of malonic acid and sebacic acid in real time; when the intensity ratio is lower than 0.5, it is determined that the temperature is lower than 265℃, and the laser power is increased at a rate of 10W / 100ms; when the intensity ratio is higher than 2.0, it is determined that the temperature is higher than 295℃, and the laser power is immediately reduced by 15%-25% until the intensity returns to the target control range of 0.5-2.0.

[0026] Further, in step S4, the filled protective gas is nitrogen or argon with a purity of 99.999%, and the filling process is controlled by a mass flow controller to slowly fill at a constant flow rate of 5 L / min until the pressure in the chamber stabilizes at 100 kPa±5 kPa, then stand still for not less than 45 seconds to ensure that the welding points are fully cooled to below 60℃.

[0027] Further, during the laser welding process in step S3, the composition detection module collects and analyzes the gas composition data at a frequency of no less than 10 Hz; the response delay of the driving control module is less than 50 ms, ensuring that the welding thermal process can implement fast and accurate closed-loop regulation.

[0028] The beneficial effects of the present application are:

[0029] Through the synergistic effect of the "vacuum cavity module" and the "atmosphere control module", laser welding in a high vacuum environment is realized, and high-purity protective gas is filled immediately after welding to cool down. This "vacuum welding, inert atmosphere cooling" process path completely isolates oxygen, so that the welding points are in an oxygen-free environment during the key stages of formation and solidification, fundamentally avoiding oxidation of the welding points, significantly reducing the risk of circuit noise caused by the degradation of the welding points due to oxidation of the streaming media audio chip, and improving the long-term working life and reliability of the product.

[0030] The real-time temperature inversion and closed-loop control mechanism based on composition detection is introduced. By analyzing the ratio of volatile gases of different boiling points, malonic acid and sebacic acid, in the pre-coated flux in real time through the "composition detection module" (Fourier transform infrared spectrometer), the real temperature of the laser action point can be indirectly and accurately inverted. The system compares this temperature signal with the set target interval and adjusts the laser power in real time and automatically. This physical energy control method based on chemical information feedback can adaptively compensate for various process fluctuations and stabilize the welding temperature in the optimal interval, effectively avoiding defects such as spatter, false welding, and chip damage caused by overheating or underheating, ensuring the high consistency and reliability of the quality of each welding point.

[0031] The "image detection module" and "composition detection module" are integrated to form a full-process quality monitoring throughout the welding process before, during, and after welding. Before welding, high-precision visual positioning and alignment calibration are performed through a microscope camera to ensure the absolute accuracy of the welding position; during welding, real-time temperature closed-loop control is performed through composition detection to ensure stable and controlled welding process; after welding, the same microscope camera is used again to collect and analyze the welding point morphology, realizing automatic quality judgment and data recording. This "positioning-process control-result inspection" integrated solution forms a complete quality closed loop, greatly improving the overall yield of the product

[0032] The cavity upper cover and the cavity tray adopt a split dynamic sealing design of "up and down movement" and "horizontal sliding", and define clear "loading station" and "sealed welding station". This layout allows the operator to perform welding in the main station while performing loading and unloading operations in the side loading station, realizing the continuous circulation of production, reducing equipment waiting time, and effectively improving the automation level and production efficiency of the overall equipment. BRIEF DESCRIPTION OF DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, the drawings in the following description only constitute some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort on the basis of these drawings.

[0034] Figure 1 is a schematic diagram of the overall architecture of the present application. Figure 1 Figure 1 is a schematic diagram of the overall architecture of the present application.

[0035] Figure 1 is a schematic diagram of the overall architecture of the present application. Figure 2 Figure 1 is a schematic diagram of the overall architecture of the present application.

[0036] Figure 1 is a schematic diagram of the overall architecture of the present application. Figure 3 Figure 1 is a schematic diagram of the overall architecture of the present application.

[0037] Figure 1 is a schematic diagram of the overall architecture of the present application. Figure 4 Figure 1 is a schematic diagram of the overall architecture of the present application.

[0038] Figure 1 is a schematic diagram of the overall architecture of the present application. Figure 5 Figure 1 is a schematic diagram of the overall architecture of the present application.

[0039] Figure 1 is a schematic diagram of the overall architecture of the present application. Figure 6 Figure 1 is a schematic diagram of the overall architecture of the present application.

[0040] Figure 1 is a schematic diagram of the overall architecture of the present application. Figure 7 Figure 1 is a schematic diagram of the overall architecture of the present application.

[0041] Figure 1 is a schematic diagram of the overall architecture of the present application. DETAILED DESCRIPTION

[0042] Embodiment 1

[0043] Figure 1 is a schematic diagram of the overall architecture of the present application. Figures 1 to 7 Figure 1 is a schematic diagram of the overall architecture of the present application. Figure 1 Figure 1 is a schematic diagram of the overall architecture of the present application.

[0044] The mainframe 20 provides rigid support for the entire device, and all modules are directly or indirectly mounted thereon.

[0045] The vacuum cavity module is a sealed environment for performing welding process, and its core includes a cavity upper cover 21 that can move up and down and a cavity tray 22 that can slide horizontally. The cavity tray 22 is installed on the main frame 20 through a precise linear guide pair and is driven by a servo motor cooperating with a ball screw, so that it can reciprocate between an open loading station located on one side of the main frame and a sealed welding station located directly below the cavity upper cover 21, and the repeated positioning accuracy is better than ±0.05 mm. The cavity upper cover 21 is driven to move up and down by a servo cylinder, and the stroke speed is adjustable within the range of 5-50 mm / s. A fluororubber sealing ring with a circular cross section is embedded in the lower edge of the cavity upper cover 21. When the cavity tray 22 carrying the circuit board 15 on which the streaming media audio chip is attached moves to the sealed welding station, the cavity upper cover 21 is pressed down to fold with the cavity tray 22, and the dynamic sealing of the welding chamber is realized by compressing the sealing ring. An upper and lower material mechanical arm 23 can be used to cooperate with the cavity tray 22 to automatically take and place the workpiece.

[0046] The atmosphere control module is in communication with the welding chamber through a vacuum pipeline and a protective gas pipeline. The module includes a vacuum pump, a gas storage tank for storing high-purity nitrogen or argon, a high-precision vacuum gauge, a mass flow controller, and a series of electromagnetic valves. The working process is as follows: after the chamber is sealed, the vacuum pump is first started to quickly reduce the pressure in the chamber from atmospheric pressure to a vacuum environment below 5 Pa; after the welding is completed, the mass flow controller is used to fill the protective gas into the chamber at a constant flow rate of 5 L / min until the pressure returns to 100 kPa±5 kPa.

[0047] The laser module includes a 1080 nm wavelength fiber laser with a maximum output power of 200 W, and a precision welding head 27. The laser generated by the laser is transmitted to the precision welding head 27 through an optical fiber.

[0048] The driving control module includes a three-dimensional adjustment frame 26 fixedly installed on the inner side of the cavity upper cover 21. The three-dimensional adjustment frame 26 adopts a high-precision ball screw and linear guide structure and is driven by a servo motor to move in the X, Y, and Z directions with micron-level precision. A multi-axis motion control card is responsible for receiving instructions and coordinating the movement of the three axes. The precision welding head 27 is fixedly installed on the three-dimensional adjustment frame 26 and is driven by the three-dimensional adjustment frame 26 to move precisely and scan in the three-dimensional space.

[0049] The image detection module and the composition detection module are highly integrated in the shell of the precision welding head 27 to form a multifunctional detection and execution terminal.

[0050] Specifically, the precision welding head 27 is internally integrated with:

[0051] The laser output fiber head 271 of the laser module and a set of f-theta focusing lens group with a focal length of 100 mm are used to focus the laser beam on the workpiece surface.

[0052] The microscope camera 272 of the image detection module has its optical axis fixedly offset at an angle of 22° to the laser beam path through a beam splitter, ensuring that the coincidence error of its field center and the laser focal point on the workpiece surface is less than 25 µm. The microscope camera 272 is equipped with a ring-shaped LED light source for high-contrast visual positioning and alignment calibration of the chip pins and the circuit board 15 pads before welding, and for image acquisition of the morphology of the completed welding point after welding.

[0053] The field optical detection component of the composition detection module includes a pair of zinc selenide lenses with high transmittance in the mid-infrared band, respectively serving as the excitation lens 273 and the collection lens 274. The optical axes of the two lenses are perpendicular to the laser beam and intersect at the laser focal point. A beam of excitation light from a mid-infrared broadband light source is conducted through a calcium fluoride optical fiber, irradiates the welding area through the excitation lens 273, and the reflected signal light is received by the collection lens 274 and conducted through another calcium fluoride optical fiber to the Fourier transform infrared spectrometer (FTIR) located on the mainframe 20. The spectral range of the spectrometer covers to with a spectral resolution of no less than Through this optical path design, in-situ real-time spectral acquisition of volatile gases in the welding area is realized. The laser focal point, the field center of the microscope camera 272, and the infrared detection spot converge in the target detection area on the workpiece surface, and the spatial position error of the three centers is accurately controlled to be less than 50 µm.

[0054] In order to ensure the angle of excitation light and collection light, two excitation lenses or two collection lenses can be provided. In the embodiment, two excitation lenses and one collection lens are provided; or two collection lenses and one excitation lens can be provided. Thus, the range of the collection light is expanded.

[0055] In addition, during the welding process, the vacuum pump continuously pumps vacuum, and the gas emitted during welding is quickly pumped away. Before being pumped away, the composition is analyzed by infrared spectrum, and has no effect on subsequent welding.

[0056] The composition detection module and the laser module are connected through the control system to realize closed-loop control. In the embodiment, the flux is a special formula halogen-free solder paste, which contains 2% malonic acid (as the first low-boiling volatile component) and 3% sebacic acid (as the second high-boiling volatile component) by mass fraction. The Fourier transform infrared spectrometer is configured to monitor the characteristic absorption peak intensity A1 of malonic acid near and the characteristic absorption peak intensity A2 of sebacic acid near The intensity of the nearby characteristic absorption peak A2 is measured, and the intensity ratio R2 = A1 / A2 is calculated. The control system has a pre-stored mapping model of the R2 ratio and the welding temperature calibrated by experiments. This model is used to invert the real-time R2 value to the current welding temperature, and through the PID control algorithm, the output power of the laser is dynamically adjusted, so that the R2 ratio is stabilized in the range of 0.5 to 2.0, which corresponds to accurately controlling the real-time temperature of the welding area in the ideal interval of 280℃±15℃.

[0057] Embodiment 2:

[0058] This embodiment describes a flow media audio chip welding anti-oxidation method using the device described in embodiment 1. The method includes the following steps:

[0059] Step S1: Feeding and chamber sealing. The upper and lower feeding mechanical arms 23 place the flow media audio chip and its circuit board 15, which have been pre-coated with the special soldering agent, on the cavity tray 22 at the feeding station. Then, the cavity tray 22 is driven to move horizontally along the guide rail 24 to the sealing and welding station. Next, the servo cylinder drives the cavity upper cover 21 to move down and press against the cavity tray 22, forming a gas-tight welding chamber through the compression of the sealing ring.

[0060] Step S2: Vacuum pumping to establish a welding environment. Start the atmosphere control module, open the vacuum pipeline valve, and the vacuum pump works to pump the pressure inside the sealed welding chamber from normal pressure to a vacuum environment below 5 Pa within 30 seconds, completely excluding oxygen.

[0061] Step S3: Laser welding and multi-component feedback temperature control. In the vacuum environment, the drive control module first generates a welding path according to the precise coordinates of the chip pins obtained by pre-scanning the microscope camera 272 of the image detection module. Then, the three-dimensional adjustment frame 26 drives the precision welding head 27 to move to the first pin according to the planned path. Start the laser to weld at the initial set power of 80W. At the same time, the composition detection module starts, and the Fourier transform infrared spectrometer collects gas spectra in real time at a frequency of 20Hz, and calculates the characteristic signal intensity ratio R2 of malonic acid and sebacic acid. The control system compares the real-time R2 value with the target range (0.5-2.0):

[0062] If the real-time R2 value is less than 0.5, it is determined that the temperature is lower than 265℃, and the control system immediately increases the laser power at a rate of 10W / 100ms.

[0063] If the real-time R2 value is higher than 2.0, it is determined that the temperature is higher than 295℃, and the control system immediately reduces the laser power by 20%.

[0064] This adjustment process continues until the R2 value returns to the target range, thereby achieving precise temperature control for each welding point during the welding process.

[0065] Step S4: Post-weld atmosphere protection cooling. When all the chip pins are welded, the laser is turned off. The atmosphere control module switches the pipeline, and the pure nitrogen with a purity of 99.999% is filled into the welding chamber at a constant flow rate of 5 L / min through the mass flow controller until the pressure in the chamber is stabilized at 100 kPa ± 5 kPa. Then, the system is stationary for 45 seconds, so that the high-temperature solder joint is slowly and uniformly cooled to below 60°C in a pure nitrogen atmosphere, completing the post-weld oxidation resistance treatment.

[0066] Step S5: Discharge and quality analysis. After the stationary state is reached, the cavity upper cover 21 is lifted, and the cavity tray 22 carrying the completed workpiece is moved back to the feeding position. The workpiece is taken out by the feeding and discharging mechanical arm 23. Finally, the system automatically generates a detailed quality report based on the recorded appearance images and composition-power control curve data of all the solder joints during the welding process, which is provided for the operator to review and archive.

[0067] Through the above device and method, the present application realizes high-precision and high-quality welding of streaming media audio chips in a high-vacuum anti-oxidation environment, and ensures the high consistency and reliability of the welding quality through real-time temperature closed-loop control based on chemical composition feedback.

[0068] Example 3:

[0069] Before step S1, there is also a step of spraying a special intelligent soldering agent and precisely spraying it in a micro area;

[0070] A low-solid-content, halogen-free, and cleaning-free soldering agent carrier is prepared. The carrier is composed of 85wt% of rosin pentaerythritol ester, 10wt% of succinic anhydride activator, and 5wt% of hydrogenated castor oil thixotropic agent, which are uniformly mixed at 60°C until clear and transparent;

[0071] After the base carrier is cooled to 40°C, the first volatile component malonic acid and the second volatile component sebacic acid are precisely added to it under high-speed shearing dispersion. The addition amount of malonic acid is 1.5wt% of the total mass of the soldering agent, and the addition amount of sebacic acid is 3.5wt%. Both of the two acids are micron-sized powders, and their purity is higher than 99.9% to ensure the purity of the infrared spectrum signal;

[0072] Finally, 60% of Type 4 lead-free solder powder with a particle size distribution of 15-25μm is added to the above mixture. The solder powder is Sn96.5Ag3.0Cu0.5 alloy. The mixture is mixed for 2 hours at a moderate speed by a three-dimensional mixer to ensure uniform suspension of the solder particles and uniform dispersion of the volatile components, and finally the special intelligent soldering agent is prepared.

[0073] Spraying of welding:

[0074] The micro-droplet spraying system integrated on the mainframe 20 is located beside the feeding station. The system has a piezoelectric micro-sprayer driven by a two-dimensional precision slide table to achieve accurate positioning relative to the chips on the cavity tray 22.

[0075] When the circuit board 15 with the chips is placed on the cavity tray 22 by the feeding and discharging mechanical arm 23, the auxiliary visual camera at the end of the micro-sprayer quickly scans the chip pin area and accurately identifies the position of each pin that needs to be welded.

[0076] The control system generates the optimal spraying path according to the identified pin coordinates. At the same time, a low-power infrared preheating lamp integrated in the micro-sprayer is started to instantaneously preheat the chip pin area, with the temperature controlled at 50±5℃. This step aims to reduce the surface tension of the flux and improve its wettability.

[0077] The micro-sprayer is driven by the two-dimensional precision slide table to move above the first target pin, at a distance of 0.5-1.0mm from the pin surface. Then, the piezoelectric driver generates pulses according to the preset waveform and frequency to push the flux out of the 50μm diameter nozzle, forming a micro-droplet of picoliter level that accurately covers the pin and pad. The thickness of the sprayed flux is achieved by controlling the number of pulses, with the final dry film thickness controlled in the ideal range of 10-15μm.

[0078] The above description of the embodiments is provided for the purpose of illustration and description. It is not intended to be exhaustive or to limit the disclosure. The individual elements or features of a particular embodiment are typically not limited to that particular embodiment, but are interchangeable with each other, and with other selected embodiments, even though not specifically shown or described in the same manner. In many instances, identical elements or features are denoted with identical reference numerals. This variation is not to be construed as a deviation from the scope of the disclosure, and all such modifications are intended to be included within the scope of the disclosure.

[0079] The example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific parts, devices, and methods, to provide a thorough understanding of the embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments can be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known procedures, well-known device structures, and well-known technologies are not described in detail.

[0080] Professional terms are used herein only for the purpose of describing particular example embodiments and are not intended to be limiting as to a scope of the disclosure. As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises," "comprising," "including," and "having" are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order in which they are discussed. It is also to be understood that additional or alternative steps can be employed.

Claims

1. A vacuum welding apparatus for streaming media audio chips, characterized in that: It includes a main frame, a vacuum chamber module, an atmosphere control module, a laser module, a drive control module, an image detection module, and a component detection module; The vacuum chamber module includes a chamber cover that can move up and down and a chamber tray that can slide horizontally. The chamber tray is used to move between the loading station and the sealing welding station and presses against the chamber cover to form a sealed welding chamber. The atmosphere control module is connected to the welding chamber and is used for evacuation and filling with protective gas; The laser module includes a laser and a precision welding head; the image detection module and the component detection module are integrated into the precision welding head. The drive control module includes a three-dimensional adjustment frame mounted on the cavity cover, used to drive the precision welding head to move; The image detection module includes a microscope camera, which is used to visually locate and align the chip pins and circuit board pads before soldering, and to acquire morphological images of the completed solder joints after soldering for soldering quality analysis. The component detection module is used to detect in real time the various gas components emitted by the flux pre-coated on the chip solder pads when heated during the laser welding process; The component detection module is connected to the laser module control. Based on the volatile mass ratio of the various gas components, it calculates the current welding temperature and performs real-time closed-loop control of the laser power accordingly. The flux contains at least a first volatile component and a second volatile component, wherein the boiling point of the first volatile component is lower than that of the second volatile component; the component detection module is configured to: calculate the ratio of the first gas component to the concentration of the second gas component in real time; establish a mapping relationship model between the ratio and the welding temperature; when the real-time calculated ratio is lower than the corresponding value of a preset temperature range, it is determined that the welding temperature is too low, and the laser power is increased; when the real-time calculated ratio is higher than the corresponding value of a preset temperature range, it is determined that the welding temperature is too high, and the laser power is decreased. The component detection module is a Fourier transform infrared spectrometer. The first volatile component is malonic acid, and the second volatile component is sebacic acid. The Fourier transform infrared spectrometer is configured to monitor and calculate the ratio of the intensity of specific absorption peaks representing different functional groups of the two acids to invert the welding temperature. The spectrometer monitors the CO stretching vibration and OH in-plane bending vibration in malonic acid molecules. Nearby absorption peak intensity And the methylene group in sebacic acid molecule Bending vibration in Nearby absorption peak intensity ; And calculate its strength ratio in real time. ; By using a preset temperature-ratio calibration curve, the ratio The value is controlled within the range of 0.5 to 2.0 to stabilize the real-time temperature of the welding area within the ideal range of 280℃±15℃.

2. The vacuum welding apparatus for streaming media audio chips according to claim 1, characterized in that, The cavity tray is mounted on the main frame via a precision linear guide pair and is driven by a servo motor and ball screw to reciprocate between the loading station and the sealing welding station. The cavity cover is driven by a servo electric cylinder to move up and down, with a stroke speed adjustable from 5 to 50 mm / s. The lower edge of the cavity cover is fitted with a circular fluororubber sealing ring. When the cavity cover is pressed down to close with the cavity tray, the sealing ring is compressed to achieve dynamic sealing of the welding cavity, ensuring the cavity is sealed.

3. The vacuum welding apparatus for streaming media audio chips according to claim 1, characterized in that, Fourier transform infrared spectrometer covers a spectral range of to Spectral resolution not lower than The spectrometer is connected to the optical detection path integrated in the precision welding head via a mid-infrared calcium fluoride optical fiber, enabling in-situ real-time spectral acquisition of volatile gases in the welding area. The relative concentration of various gas components is quantified by analyzing the intensity of absorption peaks of different characteristic functional groups.

4. The vacuum welding apparatus for streaming media audio chips according to claim 1, characterized in that, The precision welding head is a multi-functional integrated welding head. Its housing integrates: a laser output fiber collimator and a 100mm f-theta focusing lens group for outputting and focusing a 1080nm laser beam; a microscope camera in the image detection module, whose optical axis is offset at a 22° angle to the laser beam path via a beam splitter, ensuring that the overlap error between its field of view center and the laser focus on the workpiece surface is less than 25µm; the detection optical path of the component detection module includes a pair of mid-infrared transmission zinc selenide lenses, serving as the excitation lens and collection lens respectively, with their optical axes perpendicular to the laser beam and converging at the laser focus; an excitation beam from a mid-infrared broadband light source is transmitted through a calcium fluoride fiber, irradiating the welding point area through the excitation lens, and the resulting reflected signal light is received by the collection lens and transmitted through another calcium fluoride fiber to the Fourier transform infrared spectrometer; the laser focus, the camera field of view center, and the infrared detection spot converge within the target detection area on the workpiece surface; the spatial position error of the centers of these three elements is less than 50µm.

5. A method for preventing oxidation during welding of a streaming media audio chip using the apparatus described in any one of claims 1-4, characterized in that, Includes the following steps: S1: Loading and Chamber Sealing: At the loading station, a streaming media audio chip pre-coated with flux containing various volatile components is placed on the cavity tray, and then the cavity tray is driven to move horizontally to the sealing welding station; the cavity cover is pressed down to press with the cavity tray to form a sealed welding cavity; S2: Vacuuming to establish the welding environment: Activate the atmosphere control module to evacuate the inside of the welding chamber to a pressure below 5Pa; S3: Laser welding and multi-component feedback temperature control: In a vacuum environment, the drive control module drives the precision welding head to move along the path according to the positioning data pre-acquired by the image detection module; the laser is started to weld the chip pins, and at the same time the component detection module monitors the concentration of various gas components in real time, calculates their proportional relationship, and dynamically adjusts the laser power based on the mapping model between the ratio and the welding temperature to control the welding temperature within the target range. S4: Post-weld atmosphere protection and cooling: After all laser welding is completed, the welding chamber is filled with protective gas to atmospheric pressure, so that the weld joints are cooled to room temperature in the protective atmosphere; S5: Discharge and Quality Analysis: Open the cavity, move the cavity tray back to the loading station, remove the workpiece, and generate a welding quality report based on the images and composition data recorded during the welding process.

6. The method according to claim 5, characterized in that, In step S3, the component detection module monitors the characteristic signal intensity ratio R2 of malonic acid and sebacic acid in real time. When the intensity ratio is lower than 0.5, it is determined that the temperature is lower than 265°C, and the laser power is increased at a rate of 10W / 100ms. When the intensity ratio is higher than 2.0, it is determined that the temperature is higher than 295°C, and the laser power is immediately reduced by 15%-25% until the intensity ratio returns to the target control range of 0.5-2.

0.

7. The method according to claim 6, characterized in that, In step S4, the protective gas is nitrogen or argon with a purity of 99.999%. The filling process is controlled by a mass flow controller and slowly filled at a constant flow rate of 5 L / min until the pressure in the chamber stabilizes at 100 kPa ± 5 kPa. Then, it is left to stand for no less than 45 seconds to ensure that the solder joint is fully cooled to below 60°C.

8. The method according to claim 5, characterized in that, During the laser welding process in step S3, the component detection module collects and analyzes gas component data at a frequency of not less than 10Hz; the response delay of the drive control module is less than 50ms, ensuring that the welding thermal process can be rapidly and accurately controlled in a closed loop.

Images