Double-sided local plastic packaging process based on system-in-package

Abstract

The invention belongs to the technical field of integrated circuit packaging, and particularly relates to a double-sided local plastic packaging process based on system-level packaging, which comprises the following steps: S1, surface mounting: mounting an electronic component on a substrate printed with soldering paste and welding; s2, cleaning treatment is carried out, wherein pollutant removal is carried out on the welded substrate; s3, bottom filling: filling glue is injected into the bottom of the chip of the substrate and cured; s4, double-sided local plastic package: performing double-sided resin injection molding on the designated area of the substrate through a mold to form double-sided local plastic package; and S5, post-processing: carrying out curing, marking and performance testing on the plastic-packaged product, and according to the double-sided local plastic packaging process based on system-level packaging, the steps S3 to S5 are integrated, so that the service life of the surgical robot control panel is prolonged, the surgical robot control panel can stably run for a long time in the surgical process, and the risk of surgical interruption caused by equipment failure is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of integrated circuit packaging, and in particular relates to a double-sided local plastic packaging process based on system-level packaging. Background Art

[0002] Overmolding and dam-and-fill processes are common packaging methods in integrated circuit (IC) semiconductor packaging and testing. These processes involve integrally molding a substrate with epoxy resin through a mold, protecting the components on the substrate's surface. However, existing plastic encapsulation processes, such as overmolding and dam-and-fill, fail to achieve system-level modular packaging and provide adequate liquid protection. This makes control panels susceptible to failure in challenging environments, such as surgical procedures, severely impacting the performance and reliability of the equipment.

[0003] Therefore, in order to solve the above problems, it is necessary to design a double-sided local plastic packaging process based on system-level packaging. Summary of the Invention

[0004] The purpose of the present invention is to provide a double-sided partial plastic encapsulation process based on system-level packaging to solve the technical problems mentioned in the background technology.

[0005] In order to solve the above technical problems, the present invention provides a double-sided partial plastic encapsulation process based on system-level packaging, comprising the following steps: S1, Surface Mount: Place electronic components on a printed solder paste substrate and solder them; S2, cleaning treatment: remove contaminants from the substrate after welding; S3, bottom filling: inject filling glue into the bottom of the chip on the substrate and solidify it; S4, double-sided partial plastic sealing: double-sided resin injection molding is performed on the designated area of ​​the substrate through the mold to form double-sided partial plastic sealing; S5. Post-processing: Curing, marking and performance testing of the plastic-sealed products.

[0006] Furthermore, in S1, the welding adopts a reflow process, the reflow temperature is 240 to 265 degrees Celsius, and the time is 40 to 60 seconds.

[0007] Furthermore, the S2 includes: S21. Flux cleaning: Use environmentally friendly board washing water and alcohol for ultrasonic cleaning in sequence, with cleaning time of 2 minutes and 4 minutes respectively, and bake at 125 degrees Celsius for 30 minutes to remove residual flux.

[0008] Furthermore, the S2 further includes: S22, two plasma cleanings: The first cleaning is performed before the bottom fill, the cleaning time is 45 seconds, and the contaminants on the substrate surface are removed; The second cleaning is performed before plastic packaging for 10 seconds to further clean the substrate surface.

[0009] Furthermore, in said S3, the filling glue is injected by dispensing, and the filling amount is 0.02 to 0.03 grams; Curing was completed in a nitrogen oven at 130°C for 10 minutes.

[0010] Furthermore, in S4, the mold is designed according to the circuit layout of the substrate, covering only the component area to be protected, and the rest of the area remains exposed; The resin material is a high thermal conductivity, low moisture epoxy resin material with a thermal conductivity of ≥2.5W / m·K and a dielectric strength of ≥30kV / mm; The plastic sealing area covers key chips and solder joints to protect against liquid corrosion.

[0011] Furthermore, in S5, curing after plastic sealing is completed in a nitrogen oven, and the curing condition is maintained at 175 degrees Celsius for 4 hours.

[0012] Furthermore, in S5, the marking is achieved by laser irradiation, and the laser depth is 10 to 20 microns.

[0013] Furthermore, in S5, the performance test includes: electrical performance test and reliability test to ensure that the product meets the equipment standards.

[0014] The beneficial effects of the present invention are: (1) The present invention uses S3 bottom filling to enhance the connection stability between the chip and the substrate after the filling glue is cured; S4 double-sided partial plastic sealing uses high thermal conductivity, low moisture epoxy resin material to plastic seal and protect key chips and solder joints to reduce the influence of external factors; S5 post-processing curing further stabilizes the packaging structure. Combining these steps, the service life of the surgical robot control board is extended, and it can operate stably for a long time during the operation, reducing the risk of surgical interruption due to equipment failure.

[0015] (2) In the double-sided partial plastic encapsulation of the S4 of the present invention, the plastic encapsulation area covers the key chips and solder joints. The high thermal conductivity, low moisture epoxy resin material used has good resistance to liquid erosion and can effectively resist the erosion of liquids such as disinfectants during surgery, ensuring that the control board can operate normally in high humidity and liquid contact environments, meeting the high standard protection requirements of medical equipment.

[0016] (3) When the S4 of the present invention is partially encapsulated on both sides, the mold only covers the component area that needs protection, and the rest remains exposed. The thermal conductivity of the resin material used is ≥2.5W / m·K, which is conducive to heat dissipation, reduces the risk of equipment overheating, ensures that the control board maintains a stable temperature during long-term operation, and improves the thermal management capability of the entire system.

[0017] (IV) The S4 double-sided partial plastic encapsulation process of the present invention optimizes the signal transmission path. The dielectric strength of the resin material used is ≥30kV / mm, which reduces signal attenuation and interference. In high-frequency and high-power applications, it improves electrical performance and signal integrity, ensuring the accuracy and reliability of surgical robots in complex operations.

[0018] (V) In the double-sided partial plastic encapsulation step S4 of the present invention, the mold is designed according to the circuit layout of the substrate, and the encapsulation material is used only in the area that needs to be protected, which reduces material cost and manufacturing cost, reduces material waste, and improves production efficiency and resource utilization.

[0019] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention are realized and obtained by the structures particularly pointed out in the description and the drawings.

[0020] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 It is a process flow chart of a preferred embodiment of the present invention. DETAILED DESCRIPTION

[0023] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention. Example 1

[0024] like Figure 1 As shown, this embodiment provides a double-sided partial plastic encapsulation process based on system-level packaging, including the following steps: S1, Surface Mount: Place electronic components on a printed solder paste substrate and solder them; S2, cleaning treatment: remove contaminants from the substrate after welding; S3, bottom filling: inject filling glue into the bottom of the chip on the substrate and solidify it; S4, double-sided partial plastic sealing: double-sided resin injection molding is performed on the designated area of ​​the substrate through the mold to form double-sided partial plastic sealing; S5. Post-processing: Curing, marking and performance testing of the plastic-sealed products.

[0025] In S1, the soldering adopts a reflow soldering process, the reflow soldering temperature is 240 to 265 degrees Celsius, and the time is 40 to 60 seconds; among them, the reflow soldering temperature is 252 degrees Celsius and the time is 49 seconds, which is the most preferred, so that the solder paste can be fully melted and achieve good soldering between the electronic components and the substrate, so as to ensure the soldering quality and lay the foundation for subsequent processes.

[0026] The S2 includes: S21, flux cleaning: using environmentally friendly washing water and alcohol for ultrasonic cleaning in sequence, with cleaning times of 2 minutes and 4 minutes respectively, and baking at 125 degrees Celsius for 30 minutes to remove residual flux; wherein most of the flux residues are initially removed by first using environmentally friendly washing water for ultrasonic cleaning for 2 minutes; then using alcohol for ultrasonic cleaning for 4 minutes to further dissolve and remove the remaining flux. After cleaning, the substrate is placed in an oven and baked at 125 degrees Celsius for 30 minutes to completely remove the flux residue to avoid its adverse effects on subsequent processes.

[0027] The S2 also includes: S22, two plasma cleanings: the first cleaning is performed before bottom filling, with a cleaning time of 45 seconds to remove contaminants on the surface of the substrate; the second cleaning is performed before plastic sealing, with a cleaning time of 10 seconds to further purify the surface of the substrate; wherein the plasma plasma can effectively remove organic matter, oxides and other contaminants on the surface of the substrate, improve the cleanliness of the substrate surface, and enhance the adhesion of the subsequent bottom filling glue to the substrate; the second cleaning is performed before plastic sealing to further purify the substrate surface, ensure the plastic sealing effect, and avoid plastic sealing defects caused by impurities on the substrate surface.

[0028] In the S3, the glue is filled by dispensing and injection, and the filling amount is 0.02 to 0.03 grams; the curing is completed in a nitrogen oven, and the curing condition is maintained at 130 degrees Celsius for 10 minutes; curing in a nitrogen environment can prevent glue oxidation, ensure the quality of glue curing, enhance the connection strength between the chip and the substrate, and improve product reliability.

[0029] In S4, the mold is designed based on the circuit layout of the substrate, covering only the component areas that require protection, leaving the rest exposed. The resin material is a high-thermal-conductivity, low-moisture epoxy resin material with a thermal conductivity of ≥2.5W / m·K and a dielectric strength of ≥30kV / mm. The plastic-encapsulated area covers key chips and solder joints to resist liquid erosion. The mold is used to perform double-sided resin injection molding on designated areas of the substrate, forming a double-sided partial plastic encapsulation. The plastic-encapsulated area precisely covers key chips and solder joints, providing both liquid erosion resistance and optimized thermal management and electrical performance.

[0030] In S5, the curing after plastic packaging is completed in a nitrogen oven, and the curing condition is maintained at 175 degrees Celsius for 4 hours; wherein the high temperature and long-term curing can fully cross-link and cure the epoxy resin material, further stabilize the packaging structure, and improve the physical properties and chemical stability of the product.

[0031] In the above-mentioned S5, the marking is achieved by laser, and the laser depth is 10 to 20 microns; wherein the laser marking has the characteristics of high precision and good permanence, which facilitates the identification and traceability of the product.

[0032] In S5, the performance test includes: electrical performance test and reliability test to ensure that the product meets the equipment standards; the electrical performance test detects the electrical parameters of the product under different working conditions, such as resistance, capacitance, inductance, signal transmission performance, etc., to ensure that the electrical performance of the product meets the equipment standards; the reliability test simulates various environments and working conditions in actual use of the product, such as high temperature, high humidity, vibration, impact, etc., to test the reliability of the product.

[0033] In summary, through S3 bottom filling, the filling glue is cured to enhance the connection stability between the chip and the substrate; S4 double-sided partial plastic sealing uses high thermal conductivity, low-humidity epoxy resin material to protect key chips and solder joints to reduce the impact of external factors; S5 post-processing curing further stabilizes the packaging structure. Combining these steps, the service life of the surgical robot control board is extended, and it can operate stably for a long time during the operation, reducing the risk of surgical interruption due to equipment failure.

[0034] In the S4 double-sided partial plastic encapsulation, the plastic encapsulation area covers key chips and solder joints. The high thermal conductivity, low-humidity epoxy resin material used has excellent liquid erosion resistance and can effectively resist the erosion of liquids such as disinfectants during surgery. It ensures that the control board can operate normally in high humidity and liquid contact environments, meeting the high protection standards required for medical equipment.

[0035] When the S4 is partially encapsulated on both sides, the mold only covers the component areas that need protection, leaving the rest of the area exposed. The resin material used has a thermal conductivity of ≥2.5W / m・K, which facilitates heat dissipation, reduces the risk of equipment overheating, ensures that the control board maintains a stable temperature during long-term operation, and improves the thermal management capabilities of the entire system.

[0036] The S4's double-sided partial plastic encapsulation process optimizes signal transmission paths. The resin material used has a dielectric strength of ≥30kV / mm, reducing signal attenuation and interference. In high-frequency and high-power applications, it improves electrical performance and signal integrity, ensuring the accuracy and reliability of surgical robots in complex operations.

[0037] In the S4 double-sided partial plastic encapsulation step, the mold is designed according to the substrate circuit layout, and packaging materials are only used in areas that need protection, which reduces material and manufacturing costs, reduces material waste, and improves production efficiency and resource utilization.

[0038] The various devices selected in this application (components whose specific structures are not described) are all universal standard parts or components known to those skilled in the art, and their structures and principles can be known to those skilled in the art through technical manuals or conventional experimental methods.

[0039] In the description of the embodiments of the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0040] In the description of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limitations on the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0041] With the above-described preferred embodiments of the present invention as a guide, and with reference to the above description, relevant personnel are fully capable of making various changes and modifications without departing from the technical scope of this invention. The technical scope of this invention is not limited to the contents of the specification and must be determined according to the scope of the claims.

Claims

1. A double-sided partial plastic encapsulation process based on system-level packaging, characterized in that: The following steps are involved: S1, Surface Mount: Place electronic components on a printed solder paste substrate and solder them; S2, cleaning treatment: remove contaminants from the substrate after welding; S3, bottom filling: inject filling glue into the bottom of the chip on the substrate and solidify it; S4, double-sided partial plastic sealing: double-sided resin injection molding is performed on the designated area of ​​the substrate through the mold to form double-sided partial plastic sealing; S5. Post-processing: Curing, marking and performance testing of the plastic-sealed products.

2. The double-sided partial plastic encapsulation process based on system-level packaging according to claim 1, characterized in that: In S1, the soldering adopts a reflow soldering process, the reflow soldering temperature is 240 to 265 degrees Celsius, and the time is 40 to 60 seconds.

3. The double-sided partial plastic encapsulation process based on system-level packaging according to claim 1, characterized in that: The S2 includes: S21. Flux cleaning: Use environmentally friendly board washing water and alcohol for ultrasonic cleaning in sequence, with cleaning time of 2 minutes and 4 minutes respectively, and bake at 125 degrees Celsius for 30 minutes to remove residual flux.

4. The double-sided partial plastic encapsulation process based on system-level packaging according to claim 3, characterized in that: Said S2 further comprises: S22, two plasma cleanings: The first cleaning is performed before the bottom fill, the cleaning time is 45 seconds, and the contaminants on the substrate surface are removed; The second cleaning is performed before plastic packaging for 10 seconds to further clean the substrate surface.

5. The double-sided partial plastic encapsulation process based on system-level packaging according to claim 1, characterized in that: In said S3, the filling glue is injected by dispensing, and the filling amount is 0.02-0.03 g; Curing was completed in a nitrogen oven at 130°C for 10 minutes.

6. The double-sided partial plastic encapsulation process based on system-level packaging according to claim 1, characterized in that: In S4, the mold is designed according to the circuit layout of the substrate, covering only the component area to be protected, and the rest of the area remains exposed; The resin material is a high thermal conductivity, low moisture epoxy resin material with a thermal conductivity of ≥2.5W / m·K and a dielectric strength of ≥30kV / mm; The plastic sealing area covers key chips and solder joints to protect against liquid corrosion.

7. The double-sided partial plastic encapsulation process based on system-level packaging according to claim 1, characterized in that: In S5, curing after plastic packaging is completed in a nitrogen oven, and the curing condition is maintained at 175 degrees Celsius for 4 hours.

8. The double-sided partial plastic encapsulation process based on system-level packaging according to claim 1, characterized in that: In the above-mentioned S5, the marking is achieved by laser, and the laser depth is 10 to 20 microns.

9. The double-sided partial plastic encapsulation process based on system-level packaging according to claim 1, characterized in that: In S5, the performance test includes electrical performance test and reliability test to ensure that the product meets the equipment standards.

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