Integrated circuit printing process

Abstract

The present invention discloses an integrated circuit printing process, which belongs to the field of integrated circuit technology. The printing process is applied to products with a sinking frame, including: printing and patch; the printing process uses a steel mesh; the steel mesh structure includes: a printing area and a supporting area. The present invention can effectively improve many problems existing in the traditional dispensing process, such as improving the stability of solder paste printing, accurately controlling the chip tilt deviation to make it much smaller than the 40μm of the traditional process, improving the wire bonding quality, ensuring the good chip coverage in the stacked chip process, and optimizing the flatness and height control of the product. This not only helps to improve the overall performance and reliability of the product, but also can improve production efficiency and reduce production costs to a certain extent, providing an efficient and reliable technical solution for the field of integrated circuit manufacturing, with extremely high application value and market potential.

Description

Technical Field

[0001] The invention belongs to the technical field of integrated circuits, and in particular relates to an integrated circuit printing process. Background Art

[0002] In the current integrated circuit manufacturing process, the traditional pneumatic dispensing method for drawing solder paste has many disadvantages. When the solder thickness is too thin, it is very easy to cause voids, and it is difficult for traditional equipment to accurately control the drawing of thin solder. In addition, when drawing on a large area, the flatness requirements are extremely strict, and the traditional glue drawing method performs poorly in chip tilt control, and its average deviation is often greater than 40 microns, which directly leads to poor wire bonding problems. If the stacked chip process is involved, it will also cause poor coverage of the upper chip.

[0003] For products with sunken frames, glue dispensing is traditionally used. However, the characteristics of solder paste materials themselves determine that its stability in the glue dispensing process is poor, and problems such as coverage and unstable chip tilt often occur. Solder paste is relatively viscous, and when using air pressure glue dispensing, it is impossible to ensure a stable glue output and glue output position, which in turn has a negative impact on the flatness and height of the product. In particular, if the flatness of the heat sink is not good, it will seriously interfere with the uniformity of the glue amount, making problems such as unstable glue output and unstable product tilt more prominent. Summary of the invention

[0004] In view of the above situation, in order to overcome the defects of the prior art, the present invention designs a steel mesh structure containing a printing area and a supporting area and applies it to the integrated circuit printing process, replaces the traditional pneumatic dispensing with steel mesh printing, opens holes in the printing area as needed, and controls the distance from the chip pad frame and its own height in the supporting area, thereby improving many problems of the traditional dispensing process, improving product performance and reliability, improving production efficiency and reducing costs.

[0005] In order to achieve the above-mentioned purpose, the following technical scheme is adopted: the present invention provides an integrated circuit printing process, the printing process is applied to products with a sinking frame, including: printing and patching;

[0006] The printing process uses a steel mesh;

[0007] The steel mesh structure includes: a printing area and a supporting area.

[0008] Furthermore, the steel screen printing area is provided with openings, and the openings correspond to the Diepads on the sinking frame, and are used for printing adhesive onto the corresponding Diepads.

[0009] Furthermore, the adhesive is solder paste.

[0010] Furthermore, the steel mesh support area is located on two sides or four sides of the sinking frame area, and the distance between the support area and the chip pad border is ≥50μm.

[0011] Furthermore, the sinking distance of the sinking frame is ≤0.3 mm.

[0012] Furthermore, the printed solder paste thickness is ≥ the sinking distance of the sinking frame + 50 μm.

[0013] The beneficial effects of the present invention are as follows: the present invention can effectively improve many problems existing in the traditional dispensing process, such as improving the stability of solder paste printing, accurately controlling the chip tilt deviation to make it much smaller than 40μm in the traditional process, improving the wire bonding quality, ensuring the good chip coverage in the stacked chip process, and optimizing the flatness and height control of the product. This not only helps to improve the overall performance and reliability of the product, but also can improve production efficiency and reduce production costs to a certain extent, providing a valuable technical solution for the field of integrated circuit manufacturing. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the cooperation between the frame and the steel mesh of the present invention;

[0015] Figure 2 It is a top view of the frame and steel mesh of the present invention.

[0016] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. They are used to explain the present invention together with the embodiments of the present invention and do not constitute a limitation of the present invention.

[0017] Legend: 1. Frame; 11. Sinking frame; 2. Steel mesh; 21. Printing area; 23. Opening; 22. Support area; 3. Solder paste. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0019] Unless otherwise defined, all professional and scientific terms used herein have the same meanings as those familiar to those skilled in the art. In addition, any methods and materials similar or equivalent to those described herein may be applied to the present invention. The preferred implementation methods and materials described herein are for demonstration purposes only and are not intended to limit the content of this application.

[0020] The experimental methods in the following examples are conventional methods unless otherwise specified, and the experimental materials used in the following examples are purchased from commercial channels unless otherwise specified.

[0021] Example

[0022] An integrated circuit printing process, the printing process is applied to a product in which the frame 1 has a sinking frame 11, including: printing and patching;

[0023] A steel mesh 2 structure is used in the printing process;

[0024] The structure of the steel mesh 2 includes: a printing area 21 and a supporting area 22. The printing area 21 has openings. The shape and size of the openings are determined according to the product structure and requirements. The distance between the supporting area 22 and the chip pad frame is ≥50μm. The height of the supporting area 22 is preferably as small as possible while ensuring that product requirements are met, the thickness of the solder paste after passing through the furnace meets the requirements, and meets customer needs.

[0025] This embodiment demonstrates a new integrated circuit printing process, which can be designed for a certain type of sinking frame product. The steel mesh used in this process includes a printing area and a support area, and is a three-dimensional design. In comparison, the traditional steel mesh printing process is mainly limited to flat printing operations, and there are obvious deficiencies in the processing of complex structures such as sinking frames. The three-dimensional design steel mesh used in this embodiment can be used for three-dimensional printing on a certain type of sinking frame product, which can effectively solve the shortcomings of traditional processes.

[0026] At the same time, compared with the traditional pneumatic dispensing method, which has many disadvantages when operating products with complex structures such as sunken frames, this embodiment uses a steel screen printing process to effectively solve the problems of poor welding effect, uneven glue distribution, and difficult to control precision in the traditional dispensing process, which can effectively improve the quality and reliability of the product.

[0027] Before the actual operation, a special steel mesh 2 needs to be prepared. This steel mesh structure is the key element of this process. It is composed of a printing area 21 and a supporting area 22. The printing area 21 is responsible for the accurate output of solder paste. The openings 23 thereon are not set randomly, but closely fit the specific structure and diversified needs of the product. The R&D team will use professional design software simulation analysis to determine the precise shape and size of the openings based on the layout of the chip pads, the direction of the circuit, and the final performance indicators of the product. For example, for high-density, small-pitch chip integration projects, the openings are designed to be narrow and long strips, which can not only ensure sufficient solder paste filling, but also avoid solder paste adhesion between adjacent pads. The size is precisely controlled at the micron level, and the tolerance range is extremely small.

[0028] The design of the support area 22 is also very particular, and its distance from the chip pad border is strictly limited to ≥50μm. This distance is the optimal value obtained through a large number of experimental verifications. When it is less than this distance, the steel mesh is easy to touch the pad during the printing process, resulting in uneven smearing of the solder paste or even damage to the pad; when it is greater than this distance, it cannot fully play the role of support and stability. In terms of height setting, we adhere to the principle of reducing the value as much as possible on the basis of meeting product performance and ensuring that the solder paste thickness meets the standard after passing the furnace. The technicians will combine the product's heat dissipation requirements, electrical connection stability requirements, and customer expectations for the thinness of the product, and use high-precision measuring instruments to repeatedly debug. For a consumer electronic product integrated circuit that focuses on portability and low power consumption, the support area height is finally locked at the minimum value that can ensure that the solder paste thickness of 0.1mm is still uniform and flat after passing the furnace, which is in line with the original design of the product to be thin and light.

[0029] Entering the printing stage, the operator accurately positions the steel mesh 2 and places it steadily on the frame 1. The sunken frame 11 of the frame 1 fits the steel mesh well, effectively avoiding unnecessary accumulation and overflow of solder paste. The printing equipment uniformly and accurately squeezes the solder paste 3 through the opening 23 of the printing area 21 according to the preset program and applies it on the chip pad. Thanks to the exquisite design of the steel mesh structure, the solder paste output is stable and the landing point is accurate. There is no tailing or interruption in the whole process, and the flatness deviation is controlled within a very small range.

[0030] After printing is completed, the patch process is immediately carried out. With the help of advanced visual recognition system, the patch equipment can quickly lock the chip position and firmly attach the chip to the solder paste-coated pad with micron-level accuracy. Due to the ideal solder paste printing effect, the tilt deviation of the chip after bonding is greatly reduced, which is far better than the 40μm deviation value of traditional processes. The precise bonding ensures the high-quality completion of subsequent wire bonding and eliminates adverse conditions such as cold soldering and open circuit.

[0031] In the application scenario of the stacked chip process, this process has shown its advantages. With the support of precise solder paste and stable bonding, the upper chip has excellent coverage, stable and reliable electrical connection, and effectively improves the yield rate of multi-layer chip integrated products. After mass production verification, products using this integrated circuit printing process not only far exceed traditional process products in performance and reliability, but also improve production efficiency and reduce costs, bringing significant economic benefits and technological upgrades to the integrated circuit manufacturing industry.

[0032] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

[0033] The present invention and its implementation methods are described above, which is not restrictive. The drawings are only one of the implementation methods of the present invention, and the actual application is not limited thereto. In short, if ordinary technicians in the field are inspired by it and design methods and embodiments similar to the technical solution without creativity without departing from the purpose of the invention, they should all fall within the protection scope of the present invention.

Claims

1. An integrated circuit printing process, characterized in that: The printing process is applied to products with a sinking frame, including: printing and patching; The printing process uses a steel mesh; The steel mesh structure includes: a printing area and a supporting area.

2. The integrated circuit printing process according to claim 1, characterized in that: The steel screen printing area is provided with openings, and the openings correspond to the die pads on the sinking frame, and are used for printing adhesive onto the corresponding die pads.

3. The integrated circuit printing process according to claim 2, characterized in that: The adhesive is solder paste.

4. The integrated circuit printing process according to claim 2, characterized in that: The steel mesh support area is located on two sides or four sides of the sinking frame area, and the distance between the support area and the chip pad border is ≥50μm.

5. The integrated circuit printing process according to claim 2, characterized in that: The sinking distance of the sinking frame is ≤0.3mm.

6. The integrated circuit printing process according to claim 3, characterized in that: The thickness of the printed solder paste is ≥ the sinking distance of the sinking frame + 50 μm.

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