A flip chip packaging structure and method

Abstract

The present invention discloses a flip chip packaging structure and method, which relate to the field of chip packaging technology, and include a substrate, a pad, a solder bump, a chip unit and a bearing assembly, wherein a plurality of groups of pads are fixedly arranged on the upper end of the substrate, and a solder bump fixedly connected to the pad is arranged on the upper end of the pad; a bearing assembly is also arranged between the substrate and the chip unit, and the bearing assembly includes, from bottom to top, an integrally formed lower support layer, an intermediate layer and an upper support layer; the lower support layer is provided with through holes at positions corresponding to the solder bumps and the pads; the intermediate layer is provided with a plurality of mutually connected grooves at positions corresponding to the solder bumps, the intermediate layer is provided with a feed port mutually connected to the groove at a position corresponding to one of the grooves, and an exhaust hole is arranged at one end of the intermediate layer away from the feed port; the present invention improves the filling effect of the first filling glue and reduces the occurrence of air residue by arranging the bearing assembly.

Description

Technical Field

[0001] The present invention relates to the technical field related to chip packaging, and in particular to a flip chip packaging structure and method. Background Art

[0002] As chips tend to become increasingly miniaturized and thinner, packaging technology continues to develop towards high-density integration. Traditional wire bonding can hardly meet the needs and development trends of advanced packaging. Therefore, flip-chip technology came into being. Flip-chip technology has the advantages of short signal transmission path, good heat dissipation performance, low inductance and capacitance, etc. It can achieve high-density and small-size packaging and has broad prospects in practical applications.

[0003] The traditional flip chip packaging process is to first use a flowing bottom fill process to package, and then overmold the entire chip. Although material and process research has been improving, the bottom fill process is still one of the longest-lasting processes in the entire packaging process. In order to optimize the packaging process and reduce costs without affecting reliability, the molded bottom fill process came into being. This process can combine the flowing bottom fill process with the overmold process. The molded filler can not only fill the gap between the chip and the substrate, but also overmold the entire chip. The advantage of the molded bottom fill process is that the bottom fill process and the plastic encapsulation process are combined into one, thereby shortening the process time.

[0004] However, during the packaging process, when injecting the filling glue into the mold, the geometric shape of the chip and the solder bumps at the bottom will produce greater resistance to the flow of the bottom filling glue, and the filling glue will flow disorderly during the filling process, which can easily lead to air residue and affect the filling effect. Summary of the invention

[0005] In order to solve the defects in the prior art, the present invention provides a flip chip packaging structure and method.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] The present invention provides a flip chip packaging structure, comprising:

[0008] A substrate, wherein a plurality of groups of pads are fixedly disposed on the upper end of the substrate, a solder bump fixedly connected to the pads is disposed on the upper end of the pads, and the solder bump is fixedly connected to the chip unit located on the upper end thereof;

[0009] A bearing assembly is also provided between the substrate and the chip unit, and the bearing assembly includes, from bottom to top, an integrally formed lower supporting layer, a middle layer and an upper supporting layer;

[0010] The lower support layer is provided with through holes at positions corresponding to the solder bumps and pads;

[0011] The middle layer is provided with a plurality of grooves interconnected at positions corresponding to the solder bumps, the middle layer is provided with a feed port interconnected with the groove at a position corresponding to one of the grooves, and an exhaust hole is provided at one end of the middle layer away from the feed port;

[0012] The lower supporting layer is provided with a through groove at a position corresponding to the groove and communicating with the groove.

[0013] As a preferred technical solution of the present invention, the thickness of the lower supporting layer is smaller than the thickness of the solder bump, and the thickness of the upper supporting layer is smaller than the thickness of the chip unit.

[0014] As a preferred technical solution of the present invention, the outer diameter of the through hole is not less than the outer diameter of the pad.

[0015] As a preferred technical solution of the present invention, the groove is filled with a first filling glue.

[0016] As a preferred technical solution of the present invention, an adhesive layer is coated between the substrate and the supporting component.

[0017] The present invention also provides a flip chip packaging method, comprising the following steps:

[0018] S1: providing a substrate, and disposing a plurality of welding pads on the upper end of the substrate;

[0019] S2: coating an adhesive layer at a position on the upper end of the substrate different from the pad, bonding the carrier assembly to the upper end of the substrate, and placing the pad at the through hole in the lower support layer;

[0020] S3: placing the chip unit on the carrier assembly so that the chip unit is clamped inside the upper support layer, and the solder bump is placed inside the through hole and fits the pad;

[0021] S4: completing the welding between the solder bump and the pad, and cleaning the excess solder;

[0022] S5: injecting a first filling glue into the feed port so that the first filling glue fills the inside of the groove and the through slot, and heating and curing the first filling glue.

[0023] As a preferred technical solution of the present invention, step S6 is also included: providing a mold plate covering the chip unit at the upper end of the substrate, injecting a second filling glue into the gap between the mold plate and the chip unit, heating and curing the second filling glue, and then removing the mold plate.

[0024] As a preferred technical solution of the present invention, the mold plate is provided with a glue injection port and an air outlet.

[0025] As a preferred technical solution of the present invention, the gap between the mold plate and the chip unit is between 0.1 mm and 1 mm.

[0026] As a preferred technical solution of the present invention, the injection pressure range of the first filling glue is 0.5-1.5 MPa, the curing temperature of the first filling glue is set to 120-180° C., the curing time is 5-50 min, and the viscosity of the first filling glue is 500-700 mPa·s.

[0027] The beneficial effects of the present invention are:

[0028] 1. In the present invention, a carrier component is arranged between the substrate and the chip unit, and the carrier component places multiple groups of solder bumps and pads inside the groove. After the solder bumps and pads are welded, and the first filling glue is filled into the inside of the groove through the feed port, the first filling glue will gradually flow forward along the groove, thereby improving the filling effect of the first filling glue and reducing the occurrence of air residue.

[0029] 2. In the present invention, after the carrier component is placed on the upper end of the substrate, when placing the chip unit, the chip unit can be placed inside the upper supporting layer. The upper supporting layer limits and supports the chip unit, which can improve the stability of the chip unit in the subsequent processing process, avoid shaking of the chip unit, and thus ensure the welding effect of the solder bump and the pad.

[0030] 3. In the present invention, a bearing assembly is provided including a lower supporting layer, an intermediate layer and an upper supporting layer, and a first filling glue is filled inside the intermediate layer. After the first filling glue is cured, it interacts with the intermediate layer. Compared with the filling effect of a traditional single-layer filling glue, the structural strength of the flip chip can be effectively improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0032] Figure 1 It is a cross-sectional schematic diagram of the present invention.

[0033] Figure 2 for Figure 1 A local enlarged schematic diagram of point A in the middle.

[0034] Figure 3 It is a schematic diagram of the local structure of the present invention.

[0035] Figure 4 for Figure 3 Schematic diagram of the plane structure.

[0036] Figure 5 It is a schematic diagram of the local structure of the load-bearing component.

[0037] Figure 6 Another cross-sectional schematic diagram of the present invention.

[0038] Figure 7 for Figure 6 A local enlarged schematic diagram of point B in the middle.

[0039] Figure 8 The figure is a process flow chart of the flip chip packaging method of the present invention.

[0040] In the figure: 1. substrate; 2. pad; 3. solder bump; 4. chip unit; 5. carrier component; 51. lower support layer; 512. through groove; 511. through hole; 52. middle layer; 521. groove; 522. feed port; 523. exhaust hole; 53. upper support layer; 6. first filling glue; 7. adhesive layer; 9. second filling glue. DETAILED DESCRIPTION

[0041] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0042] Embodiment 1

[0043] like Figure 1-Figure 6 As shown, a flip chip packaging structure includes a substrate 1, a pad 2, a solder bump 3, a chip unit 4 and a bearing assembly 5, wherein a plurality of pads 2 are fixedly arranged on the upper end of the substrate 1, a solder bump 3 fixedly connected to the pad 2 is arranged on the upper end of the pad 2, and the solder bump 3 is fixedly connected to the chip unit 4 located on the upper end thereof; a bearing assembly 5 is further arranged between the substrate 1 and the chip unit 4, and the bearing assembly 5 includes, from bottom to top, an integrally formed lower support layer 51, an intermediate layer 52 and an upper support layer 53; the lower support layer 51 is provided at positions corresponding to the solder bumps 3 and the pads 2 A through hole 511 is provided; the middle layer 52 is provided with a plurality of grooves 521 interconnected at a position corresponding to the solder bump 3, the middle layer 52 is provided with a feed port 522 interconnected with the groove 521 at a position corresponding to one of the grooves 521, an exhaust hole 523 is provided at one end of the middle layer 52 away from the feed port 522, the groove 521 is filled with a first filling glue 6, the lower support layer 51 is provided with a through groove 512 connected with the groove 521 at a position corresponding to the groove 521, and the setting of the through groove 512 needs to avoid the solder bump 3 and the pad 2.

[0044] Among them, by arranging the bearing assembly 5 between the substrate 1 and the chip unit 4, the bearing assembly 5 places the multiple groups of solder bumps 3 and the pads 2 inside the groove 521. After the solder bumps 3 and the pads 2 are welded, and the first filling glue 6 is filled into the inside of the groove 521 through the feed port 522, the first filling glue 6 will gradually flow forward along the groove 521, thereby improving the filling effect of the first filling glue 6 and reducing the occurrence of air residue. The setting of the exhaust hole 523 can reduce the resistance of the first filling glue 6 when it flows, and avoid the occurrence of air residue.

[0045] After the carrier assembly 5 is placed on the upper end of the substrate 1, when placing the chip unit 4, the chip unit 4 can be placed inside the upper support layer 53. The upper support layer 53 limits and supports the chip unit 4, which can improve the stability of the chip unit 4 in the subsequent processing process, avoid shaking of the chip unit 4, and thus ensure the welding effect of the solder bump 3 and the pad 2;

[0046] By setting the bearing component 5 including the lower supporting layer 51, the middle layer 52 and the upper supporting layer 53, and filling the middle layer 52 with the first filling glue 6, the first filling glue 6 interacts with the middle layer 52 after curing. Compared with the filling effect of the traditional single-layer filling glue, the structural strength of the flip chip can be effectively improved. At the same time, after the first filling glue 6 is filled in the groove 521, the substrate 1, the bearing component 5 and the chip unit 4 can be tightly combined, thereby improving the molding quality of the flip chip and thereby improving the service life of the flip chip.

[0047] The multiple grooves 521 connected to each other are in a multi-S shape. When the first filling glue 6 enters from the position of the feed port 522, the first filling glue 6 will gradually fill and move along the multiple grooves 521. During the filling process, the first filling glue 6 will cover the solder bumps 3 exposed at the position of the grooves 521, and fill the through grooves 512 at the same time. Finally, the lower end of the solidified first filling glue 6 is tightly fitted with the substrate 1, the middle position is tightly fitted with the supporting component 5 and the solder bump 3, and the upper end is tightly fitted with the chip unit 4, finally realizing a tight connection between the chip unit 4 and the substrate 1. The first filling glue 6 is used in conjunction with the supporting component 5 to effectively disperse the stress on the chip unit 4. This arrangement can avoid the stress caused by the mismatch of the thermal expansion coefficient (CTE) between the chip unit 4 and the substrate 1, reduce the probability of welding failure or cracks, and thus improve the reliability of the product.

[0048] It should be noted that the material of the bearing component 5 is a polymer material. Optionally, the bearing component 5 is one of polyimide, epoxy resin, polystyrene, polymethyl methacrylate, thermoplastic polyester, polyurethane or polytetrafluoroethylene. These polymer materials can provide necessary support and protection effects due to their unique physical and chemical properties. The selection of a suitable material as the bearing component 5 will be based on specific application requirements, environmental conditions and cost considerations.

[0049] The first filling glue 6 is usually epoxy resin. In order to optimize the performance of epoxy resin, materials such as silicon dioxide are usually added to the epoxy resin to make it exhibit characteristics such as high modulus, low CTE, low moisture absorption and good adhesion.

[0050] Further, if Figure 5 As shown, the thickness of the lower support layer 51 is less than the thickness of the solder bump 3. This arrangement allows the upper half of the solder bump 3 to be exposed at the groove 521. After being covered by the first filling glue 6, the structural stability of the solder bump 3 can be effectively improved, and the solder bump 3 can be prevented from being separated from the pad 2, thereby reducing the risk of solder joint failure.

[0051] The thickness of the upper support layer 53 is smaller than that of the chip unit 4 , which facilitates subsequent filling and sealing of the entire chip unit 4 , so that the entire package forms a more compact structure, providing more possibilities for the design of high-density integrated circuits.

[0052] Further, if Figure 2 As shown, the outer diameter of the through hole 511 is not less than the outer diameter of the pad 2, ensuring that there is sufficient contact area between the pad 2 and the solder bump 3, thereby improving the stability of the soldering contact. This design strategy effectively avoids uneven soldering and poor contact caused by limited solder flow due to insufficient aperture. The optimized outer diameter design can also assist the smooth flow of solder, and the designed through groove 512 structure helps to guide excess solder out, reduce the risk of short circuit, and ensure the long-term stable operation of the device. Furthermore, this design can make the subsequent cleaning process simpler and more effective, reduce the difficulty and cost of cleaning in the production process, and thus improve production efficiency.

[0053] Further, if Figure 2As shown, an adhesive layer 7 is coated between the substrate 1 and the carrier component 5. The adhesive layer 7 can not only effectively improve the bonding strength between the two, but also buffer the stress caused by temperature changes during thermal expansion and contraction, thereby avoiding delamination and cracking caused by temperature differences. The adhesive layer 7 should be selected from a material with appropriate fluidity to ensure that it can be evenly distributed and fill all tiny surface defects during assembly, thereby increasing the fit. In addition, the material selected for the adhesive layer 7 must have excellent heat resistance and electrical insulation to maintain the stability and safety of the packaging structure under high temperature and humid conditions. Optionally, the adhesive layer 7 is a silicone adhesive layer 7. Once the silicone adhesive layer 7 is cured, the chemical cross-linking network formed by the silicone adhesive layer 7 can provide lasting bonding strength. This structure enables the adhesive to resist separation and peeling, providing long-term stability. The silicone adhesive can work stably in a wide temperature range of -50°C to 250°C, and can withstand short-term high temperatures. At the same time, it can effectively buffer mechanical stress and improve reliability for long-term use.

[0054] Embodiment 2

[0055] The components that are the same or corresponding to those in the first embodiment are marked with the same reference numerals as those in the first embodiment. For the sake of simplicity, only the differences from the first embodiment are described below. The second embodiment differs from the first embodiment in that:

[0056] like Figure 8 As shown, the present invention also provides a flip chip packaging method, comprising the following steps:

[0057] S1: providing a substrate 1, and disposing a plurality of pads 2 on the upper end of the substrate 1;

[0058] Substrate 1 usually uses high-performance insulating materials, such as FR-4 (epoxy resin glass fiber composite material) or ceramics, to ensure excellent mechanical strength and electrical insulation. Before use, the surface of substrate 1 needs to be cleaned to remove any contaminants that may affect the bonding strength, such as grease, dust and moisture. Isopropyl alcohol or ultrasonic cleaning can be used for pretreatment to ensure that the surface of pad 2 is smooth.

[0059] S2: coating an adhesive layer 7 at a position on the upper end of the substrate 1 different from the pad 2, and bonding the carrier assembly 5 to the upper end of the substrate 1, while placing the pad 2 at the through hole 511 in the lower support layer 51;

[0060] The coating process can be applied by coating or spraying to the adhesive, ensuring that the coating thickness is uniform so that small surface defects can be fully filled when the carrier component 5 is attached. The carrier component 5 is accurately placed on the adhesive layer 7, and appropriate pressure is applied to ensure that it is in full contact with the surface of the substrate 1. It is fixed with a mechanical clamp to allow the adhesive to solidify and form a stable connection. While bonding the carrier component 5, ensure that the pad 2 is correctly docked into the through hole 511 of the lower support layer 51. Prior to this, the through hole 511 needs to be pre-treated and cleaned to enhance the bonding strength between the solder paste and the pad 2;

[0061] S3: placing the chip unit 4 on the carrier assembly 5 so that the chip unit 4 is clamped inside the upper support layer 53, and the solder bump 3 is placed inside the through hole 511 and is arranged in contact with the pad 2;

[0062] Placing the chip unit 4 An automatic placement machine can be used to accurately place the chip unit 4 on the carrier component 5 to ensure that it is aligned and fully engaged in the upper support layer 53. Special attention should be paid to the direction and position of the chip unit 4 to avoid misconnection during subsequent welding. At the same time, it is also necessary to ensure that the solder bump 3 is placed in the through hole 511 and is in close contact with the pad 2. At this stage, pressure may need to be applied to ensure that the solder bump 3 is perfectly combined with the pad 2 and to avoid failures caused by thermal expansion.

[0063] S4: completing the welding between the solder bump 3 and the solder pad 2, and cleaning the excess solder;

[0064] Use reflow soldering or wave soldering to melt the solder bump 3 and form a firm connection with the pad 2. Keep the soldering temperature and time stable to avoid damage to the substrate 1 or solder joint defects caused by overheating. After soldering, clean the excess solder and flux to improve the quality of the product submitted to the customer. Ultrasonic cleaning or chemical solvents (such as board washing water) can be used to clean to ensure electrical insulation and neat appearance.

[0065] S5: injecting the first filling glue 6 into the feed port 522 so that the first filling glue 6 fills the inside of the groove 521 and the through groove 512, and heating and curing the first filling glue 6;

[0066] The first filling glue 6 is uniformly injected into the preset groove 521 and the through groove 512 by a dedicated glue injection machine to ensure that no bubbles are generated and all areas are covered at the same time. The curing process adopts a thermal curing method to heat the filling glue to ensure that it is uniformly cured. The curing temperature and time need to be strictly controlled to prevent the material performance from being degraded due to overheating. During the curing stage, it can be cured by infrared rays or ovens.

[0067] The step S6 is also included: providing a mold plate covering the chip unit 4 at the upper end of the substrate 1, injecting a second filling glue 9 into the gap between the mold plate and the chip unit 4, heating and curing the second filling glue 9, and then removing the mold plate;

[0068] The mold plate is usually made of a material with good heat resistance and rigidity, such as aluminum alloy or polymer material. The second filling glue 9 is injected into the gap between the mold plate and the chip unit 4 through the injection port to ensure that all gaps are covered and a complete seal is formed. This step requires the injection process to be fast and uniform to prevent the second filling glue 9 from shifting before hardening. Similarly, after the second filling glue 9 is injected, it also needs to be cured.

[0069] Further, if Figure 6-Figure 7 As shown, the mold plate is provided with a glue injection port and an air outlet, which is based on the same principle as the feed port 522 and the air outlet 523 provided on the middle layer 52. The glue injection port and the air outlet design on the mold plate need to be reasonably arranged to achieve the best fluidity and gas escape effect. The diameter of the glue injection port must be accurately tested to ensure that the fluidity of the colloid will not be restricted during the injection of the second filling glue 9. At the same time, the air outlet must be sufficient to quickly discharge the gas generated inside the mold to prevent bubbles from being generated and causing defects. This design enables the second filling glue 9 to quickly and effectively fill all gaps between the mold and the chip, providing uniform physical and electrical properties for the final product. In addition, when injecting, temperature control and accurate setting of the injection pressure are also important steps to ensure the performance of the filling glue, which can greatly improve the matching and overall performance of the mold plate.

[0070] Generally speaking, the temperature during the injection process is between 20°C-60°C. For most filling materials, especially thermoplastic and thermosetting polymers, the optimal injection temperature is usually set between 30°C-50°C.

[0071] The gap between the mold plate and the chip unit 4 is between 0.1mm and 1mm. This setting can ensure that the second filling glue 9 fills all tiny gaps and achieves the best operating effect. This range is intended to prevent problems such as poor colloid flow and incomplete filling caused by excessive gaps, and effectively avoid the formation of voids after curing. At the same time, it also prevents excessive friction between the mold and the chip unit 4, resulting in jamming during assembly. It can greatly improve the stability and effectiveness of the filling process and ensure the quality of the final flip-chip package.

[0072] Furthermore, the injection pressure of the first filling glue 6 is in the range of 0.5-1.5 MPa. Confirming the appropriate injection pressure is conducive to the filling glue successfully filling the groove 521 while ensuring fluidity, and avoiding the occurrence of gas entrapment;

[0073] The curing temperature of the first filling glue 6 is set to 120-180°C and the curing time is 5-50min, which ensures that the filling glue does not vaporize or cure prematurely during the curing process, thereby ensuring good bonding and sealing of the chip;

[0074] The viscosity of the first filling glue 6 is 500-700 mPa·s, which can ensure that the filling glue has a certain fluidity when injected, and can also restore a certain strength after curing, thereby promoting the long-term stability and functionality of the flip chip;

[0075] Similarly, various parameters of the second filling glue 9 in the injection process are the same as those of the first filling glue 6 .

[0076] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A flip chip packaging structure, characterized in that: include: A substrate (1), wherein a plurality of groups of solder pads (2) are fixedly arranged at the upper end of the substrate (1), a solder bump (3) fixedly connected to the solder pad (2) is arranged at the upper end of the solder pad (2), and the solder bump (3) is fixedly connected to a chip unit (4) located at the upper end thereof; A bearing assembly (5) is further provided between the substrate (1) and the chip unit (4), wherein the bearing assembly (5) comprises, from bottom to top, an integrally formed lower supporting layer (51), an intermediate layer (52), and an upper supporting layer (53); The lower support layer (51) is provided with through holes (511) at positions corresponding to the solder bumps (3) and the pads (2); The intermediate layer (52) is provided with a plurality of mutually connected grooves (521) at positions corresponding to the solder bumps (3); the intermediate layer (52) is provided with a feed port (522) mutually connected with the groove (521) at a position corresponding to one of the grooves (521); and an exhaust hole (523) is provided at one end of the intermediate layer (52) away from the feed port (522); The lower supporting layer (51) is provided with a through groove (512) at a position corresponding to the groove (521) and connected to the groove (521); The groove (521) is filled with a first filling glue (6).

2. The flip chip packaging structure according to claim 1, characterized in that: The thickness of the lower support layer (51) is smaller than the thickness of the solder bump (3), and the thickness of the upper support layer (53) is smaller than the thickness of the chip unit (4).

3. The flip chip packaging structure according to claim 1, characterized in that: The outer diameter of the through hole (511) is not less than the outer diameter of the pad (2).

4. The flip chip packaging structure according to claim 1, characterized in that: An adhesive layer (7) is coated between the substrate (1) and the bearing assembly (5).

5. A flip chip packaging method, applied to the flip chip packaging structure according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1: providing a substrate (1), and arranging a plurality of welding pads (2) on the upper end of the substrate (1); S2: coating an adhesive layer (7) at a position on the upper end of the substrate (1) different from the soldering pad (2), bonding the carrier component (5) to the upper end of the substrate (1), and placing the soldering pad (2) at the through hole (511) in the lower support layer (51); S3: placing the chip unit (4) on the carrier assembly (5) so that the chip unit (4) is clamped inside the upper support layer (53), and the solder bump (3) is placed inside the through hole (511) and is arranged in affixed relation with the solder pad (2); S4: completing the welding between the solder bump (3) and the solder pad (2), and cleaning the excess solder; S5: injecting the first filling glue (6) into the feed port (522) so that the first filling glue (6) fills the inside of the groove (521) and the through groove (512), and heating and curing the first filling glue (6).

6. The flip chip packaging method according to claim 5, characterized in that: The method further comprises step S6: providing a mold plate covering the chip unit (4) at the upper end of the substrate (1), injecting a second filling glue (9) into the gap between the mold plate and the chip unit (4), heating and curing the second filling glue (9), and then removing the mold plate.

7. The flip chip packaging method according to claim 6, characterized in that: The mold plate is provided with a glue injection port and an air outlet.

8. The flip chip packaging method according to claim 7, characterized in that: The gap between the mold plate and the chip unit (4) is between 0.1 mm and 1 mm.

9. The flip chip packaging method according to claim 6, characterized in that: The injection pressure range of the first filling glue (6) is 0.5-1.5 MPa, the curing temperature of the first filling glue (6) is set to 120-180°C, the curing time is 5-50 minutes, and the viscosity of the first filling glue (6) is 500-700 mPa·s.

Images