Novel liquid state conduction connection structure and manufacturing method thereof

Abstract

The invention provides a novel liquid state conduction connection structure and a manufacturing method thereof, and belongs to the technical field of chip packaging. Comprising a substrate, a conduction pipe is mounted on the top of the substrate, the top of the conduction pipe is connected with a chip, the conduction pipe is filled with conduction liquid, and signal transmission between the substrate and the chip is achieved through the conduction liquid. The space between the chip and the substrate is filled with liquid conduction liquid, and conduction is achieved through the conduction liquid. A bumping manufacturing site is omitted, a bump does not need to be grown on a chip welding spot, the problem of welding failure caused by cracks of a product in the production and use process is avoided, the conducting liquid is in a liquid state, and even if the conducting liquid shakes violently or is impacted by external force, the liquid state does not have cracks, so that a conducting fault is avoided.

Description

Technical Field

[0001] The present invention belongs to the technical field of chip packaging, and in particular relates to a novel liquid conductive connection structure and a manufacturing method thereof. Background Art

[0002] like Figure 1 As shown in the figure, the existing flip chip (FC) packaging technology, as an important technology in the field of semiconductor packaging, is centered on achieving accurate and stable electrical connection between the chip and the substrate through precise intermediary components such as tin caps or tin balls. These tin intermediaries, like bridges, carry the complex and intensive signal transmission tasks between the chip and the substrate, and build a series of critical electrical conduction paths. However, although this connection method is technically quite mature and is widely used in various electronic products, it still has an inherent defect that cannot be ignored.

[0003] Tin, as a relatively soft metal material, often shows high sensitivity to external mechanical interference or stress changes due to its physical properties. Even extremely slight external forces, such as vibration, impact, or thermal expansion and contraction caused by temperature changes, can cause tiny cracks inside the tin connection points. These seemingly insignificant cracks are actually like time bombs hidden inside electronic products. With the passage of time and the continuous action of stress, they will gradually expand and spread, eventually causing the phenomenon of open circuit welding. Once an open circuit welding occurs, the electrical signal will not be able to be smoothly transmitted between the chip and the substrate, resulting in the failure of the entire electronic product, seriously damaging the reliability and service life of the product.

[0004] What is more serious is that this soldering open circuit problem caused by micro cracks in the tin connection point is often difficult to be discovered in time during the early detection of the product. This is because micro cracks may not have a significant impact on the performance of the product in the initial stage. They can only be detected when they expand to a certain extent and cause obvious electrical failures. At this time, the best time for repair has often been missed, causing great inconvenience and economic losses to users.

[0005] Therefore, how to overcome the micro-crack problem of tin connection points in traditional FC products and improve product reliability and service life has become an important issue that needs to be urgently addressed in the current field of semiconductor packaging technology.

[0006] In order to overcome this problem, the present invention proposes an innovative solution - using a special liquid conductive fluid to fill the tiny gap between the chip and the substrate, and realizing the transmission of electrical signals through this conductive fluid. Summary of the invention

[0007] The purpose of the present invention is to overcome the problem that the existing chip and substrate connection technology uses solder balls for connection, which is prone to cracks and causes welding open circuits, resulting in the inability to transmit electrical signals between the chip and the substrate, and to provide a new liquid conductive connection structure and a manufacturing method thereof.

[0008] In order to achieve the above object, the present invention adopts the following technical solution: A novel liquid conduction connection structure comprises a substrate, a conduction tube is mounted on the top of the substrate, a chip is connected to the top of the conduction tube, and a conduction liquid is filled in the conduction tube.

[0009] The substrate includes a plurality of first welding points, and the chip includes a plurality of second welding points.

[0010] Two ends of the conducting tube correspond to the positions of the first welding point and the second welding point.

[0011] The conducting liquid connects the second welding point and the first welding point.

[0012] The substrate and the conducting tube are bonded together by adhesive.

[0013] The conducting tube and the chip are bonded together by adhesive.

[0014] The adhesive can be cured after low-temperature baking.

[0015] A method for manufacturing a novel liquid conductive connection structure, the specific steps are as follows: The adhesive is evenly applied around the first solder joint of the substrate; the conducting tube is mounted on the substrate, the mounting position of the tube corresponds to the position of the first solder joint of the substrate one by one, and is fixed on the substrate by the adhesive, and low-temperature baking is performed to solidify the adhesive; the adhesive is applied to the top of the other side of the conducting tube; an appropriate amount of conducting liquid is injected into each conducting tube; the chip is mounted in the conducting tube, the applied adhesive contacts the second solder joint of the chip, and the adhesive is solidified by secondary low-temperature baking, and the conducting liquid connects the second solder joint of the chip and the first solder joint of the substrate to achieve conduction.

[0016] The adhesive is evenly applied around the first welding point and the second welding point using an extremely fine needle.

[0017] By controlling the moving speed and flow rate of the needle, the coating thickness of the adhesive can be ensured to be uniform and without omissions.

[0018] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a novel liquid conductive connection structure and a manufacturing method thereof, comprising a substrate, a conductive tube mounted on the top of the substrate, a chip connected to the top of the conductive tube, a conductive liquid filled inside the conductive tube, and the signal transmission between the substrate and the chip is achieved through the conductive liquid. Liquid conductive liquid is filled between the chip and the substrate, and conduction is achieved through the conductive liquid. The bumping production site is omitted, and there is no need to grow bumps on the chip solder joints, thereby avoiding the problem of cracks in the product during production and use, resulting in welding failure. The conductive liquid itself is liquid, and even if it is violently shaken or impacted by external forces, the liquid will not crack, resulting in conduction failure.

[0019] Furthermore, the conducting tube is connected and sealed to the chip and the substrate respectively by adhesive to prevent the conducting liquid from diffusing to other areas.

[0020] Furthermore, the present invention omits the reflow process and the underfill process, reduces the damage and warping problems of the chip and the substrate caused by the thermal process, and saves costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0022] Figure 1 It is a structural schematic diagram of an existing flip chip; Figure 2 It is a structural diagram of the device of the present invention; Figure 3 It is a schematic diagram of the structure of the conducting part in the present invention; Figure 4 It is a schematic diagram of the substrate structure in the present invention; Figure 5 This is a schematic diagram of the structure of the adhesive bonding substrate in the present invention; Figure 6 This is a schematic diagram of the installation of the conducting pipe in the present invention; Figure 7 It is a schematic diagram of the bonding of the adhesive in the present invention; Figure 8 It is a schematic diagram of the chip conduction substrate structure in the present invention.

[0023] Explanation of the reference numerals in the figure: 1, substrate; 11, first solder joint; 2, conducting tube; 3, adhesive; 4, chip; 41, second solder joint; 5, conducting liquid. DETAILED DESCRIPTION

[0024] In the following, only some exemplary embodiments are briefly described. As those skilled in the art will appreciate, the described embodiments may be modified in various ways without departing from the spirit or scope of the present invention. Therefore, the drawings and descriptions are considered to be exemplary and non-restrictive in nature.

[0025] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0026] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0027] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0028] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0029] It should be understood that when used in this specification and the appended claims, the terms "include" and "comprises" indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0030] It should also be understood that the terms used in the present specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the present specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0031] It should be further understood that the term "and / or" used in the present description and the appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0032] Various structural schematic diagrams of the embodiments disclosed in the present invention are shown in the accompanying drawings. These figures are not drawn to scale, and some details are magnified and some details may be omitted for the purpose of clear expression. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships therebetween are only exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may additionally design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0033] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0034] Example 1 A new type of liquid conductive connection structure, the structure of which is as follows: like Figure 2~3 As shown, a novel liquid conductive connection structure includes a substrate 1, a plurality of first solder joints 11 are provided on the substrate 1, a conductive tube 2 is mounted on the substrate 1, and the position of the conductive tube 2 corresponds one-to-one with the first solder joints 11 on the substrate 1, the conductive tube 2 is fixed on the substrate 1 by an adhesive 3, the adhesive 3 is evenly coated around the first solder joints 11 of the substrate 1 and the top of the conductive tube 2, the adhesive 3 is used to fix the conductive tube 2 and the chip 4, a conductive liquid 5 is injected into the conductive tube 2, the chip 4 includes a plurality of second solder joints 41, and the second solder joints 41 of the chip 4 and the first solder joints 11 of the substrate 1 are connected by the conductive liquid 5.

[0035] Preferably, the adhesive 3 can be cured after low-temperature baking to firmly fix the conducting tube 2 and the chip 4 .

[0036] Example 2 like Figures 4 to 8As shown, a method for manufacturing a novel liquid conductive connection structure is as follows: S1: Pretreatment of substrate 1: Use a cleaning agent to clean the surface of substrate 1 to remove oil stains and impurities, and then blow dry with nitrogen to ensure the cleanliness of the surface of substrate 1.

[0037] S2: Applying adhesive 3: Connect a specially made very fine needle to a precision glue coating device, and according to a preset glue coating path, evenly apply the adhesive 3 around the first welding point 11 of the substrate 1. During the glue coating process, the moving speed and flow rate of the needle are controlled to ensure that the coating thickness of the adhesive 3 is uniform and without omission.

[0038] S3: Mounting the via 2: Using precision mounting equipment, the via 2 is precisely aligned with the first solder joint 11 on the substrate 1 for mounting. During the mounting process, the position and angle of the via 2 are monitored in real time by a visual recognition system to ensure that each via 2 is aligned with the corresponding first solder joint 11.

[0039] S4: low temperature baking: put the mounted substrate 1 into a low temperature baking oven, and set the baking temperature and time according to the type and curing characteristics of the adhesive 3. During the baking process, ensure that the temperature and humidity in the baking oven are uniform to avoid uneven curing of the adhesive 3.

[0040] S5: Apply adhesive glue 3 to the top of the conducting tube 2: Use the special needle in step 2 to evenly apply adhesive glue 3 to the top of the other side of the conducting tube 2. During the application of glue, pay attention to controlling the moving speed and flow rate of the needle to ensure that the coating thickness of the adhesive glue 3 is moderate and uniform.

[0041] S6: Injecting the conducting liquid 5: Connect the cleaned needle to the conducting liquid injection device, and accurately inject the conducting liquid 5 into each conducting tube 2. During the injection process, the injection speed and pressure are controlled to ensure that the injection amount of the conducting liquid 5 is moderate and evenly distributed.

[0042] S7: Mounting chip 4: Use precision mounting equipment to accurately align chip 4 with conductive tube 2 for mounting. During the mounting process, the position and angle of chip 4 are monitored in real time by a visual recognition system to ensure that the second solder joint 41 of chip 4 is in good contact with conductive liquid 5 in conductive tube 2.

[0043] S8: Second low-temperature baking: Place the mounted chip 4 in a low-temperature baking oven for secondary baking to further cure the adhesive 3. During the baking process, the temperature and humidity in the baking oven also need to be uniform to ensure that the adhesive is completely cured.

[0044] S9: Quality inspection: Perform quality inspection on the manufactured electronic component structure, including electrical test, appearance inspection, etc. The electrical test mainly checks whether the conduction performance between the chip 4 and the substrate 1 is good; the appearance inspection mainly checks whether the mounting of the conducting tube 2, chip 4 and adhesive 3 is flat, free of bubbles, cracks and other defects.

[0045] Preferably, the substrate 1 is a ceramic or organic substrate with high thermal conductivity and good electrical properties, on which a pattern corresponding to the second solder joint 41 of the chip has been pre-processed.

[0046] Preferably, the conducting tube 2 selects a micro metal tube or plastic tube with precise size, smooth inner wall and chemical corrosion resistance as the conducting tube to ensure good contact between it and the first solder joint 11 of the substrate and the second solder joint 41 of the chip. The conducting tube with precise size can reduce assembly errors, ensure the continuity and stability of electrical signal transmission, and avoid signal attenuation or interruption caused by poor contact. The smoothness of the inner wall is another crucial factor. The smooth inner wall can not only reduce the resistance of the fluid (such as conductive liquid or coolant) when flowing in the tube, improve the transmission efficiency, but also effectively prevent the accumulation or deposition of particles, thereby maintaining the long-term cleanliness and functionality of the conducting tube. This is crucial to maintain the clear transmission of electrical signals and the overall performance of the system. Chemical corrosion resistance is also not to be ignored. In the process of electronic packaging, the conducting tube may be exposed to various chemicals, such as solder, cleaning agents, packaging materials, etc. Therefore, it is crucial to select a material with excellent chemical corrosion resistance, which can not only extend the service life of the conducting tube, but also ensure that it maintains stable physical and electrical properties in a complex and changing chemical environment.

[0047] Preferably, the adhesive 3 uses epoxy resin or polyimide adhesive with low temperature curing, high adhesion and low shrinkage to ensure the firm fixation of the conductive tube 2 and the chip 4. The low temperature curing property means that the adhesive can complete the curing process at a relatively low temperature, which is crucial for protecting the chip 4 from high temperature damage, and can also simplify the production process and reduce energy consumption. High adhesion is another important characteristic of the adhesive 3. It ensures that the conductive tube 2 and the chip 4 can form a tight bond, and effectively prevents loosening or falling off caused by external factors such as vibration and temperature changes. This strong adhesion not only improves the mechanical stability of the entire assembly, but also ensures the stable transmission of electrical signals, thereby ensuring the performance and reliability of the equipment. In addition, low shrinkage is another key factor that cannot be ignored when selecting the adhesive 3. During the curing process, if the shrinkage rate of the adhesive is too large, it may cause a gap between the conductive tube 2 and the chip 4, thereby affecting the quality and stability of the electrical connection. The low shrinkage adhesive can minimize the volume change during the curing process, ensuring a close fit between the conducting tube 2 and the chip 4, thereby improving the electrical performance and durability of the entire assembly.

[0048] Preferably, the conductive liquid 5 selects liquid metals (such as gallium, indium, etc.) or conductive polymers with high conductivity, low viscosity, and good chemical stability as the conductive liquid to ensure good electrical connection. Specifically, liquid metals, such as gallium, indium, etc., are ideal choices due to their excellent conductive properties. These liquid metals not only have excellent conductive properties, but also have low viscosity, which means that they encounter less resistance when flowing and can fill the conductive channel more smoothly, thereby ensuring the stable transmission of electrical signals. In addition, liquid metals also exhibit good chemical stability and are not easy to react chemically with other materials, thereby extending the service life of the conductive liquid and improving the reliability of the entire system.

[0049] In addition to liquid metal, conductive polymer is also one of the important candidate materials for conductive liquid 5. Conductive polymer has conductive properties through a specific synthesis process, while maintaining the flexibility and processability of the polymer. This material not only has similar conductive properties to liquid metal, but may also show better adaptability and adjustability in certain application scenarios. In addition, conductive polymers usually have good environmental adaptability and can maintain stable conductive properties under different temperature and humidity conditions, which is crucial to ensure the long-term reliability of electrical connections.

[0050] Preferably, the chip 4 is an integrated circuit chip that meets the design requirements, on which the second solder joints 41 corresponding to the conducting tube 2 have been pre-processed.

[0051] After manufacturing is completed, the electronic component structure is encapsulated according to the design requirements to protect it from the influence of the external environment.

[0052] Finally, it should be noted that the above embodiments only describe the basic principles and main features of the present invention and the advantages of the present invention. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the attached claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any figure mark in the claims should not be regarded as limiting the claims involved.

[0053] In addition, it should be understood that although this specification is described in accordance with the implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation modes that can be understood by those skilled in the art. The above content is only to illustrate the technical idea of ​​the present invention, and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution according to the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A new type of liquid conductive connection structure, characterized in that: The invention comprises a substrate (1), a conducting tube (2) is mounted on the top of the substrate (1), the top of the conducting tube (2) is connected to a chip (4), and the conducting tube (2) is filled with a conducting liquid (5).

2. A novel liquid conductive connection structure according to claim 1, characterized in that: The substrate (1) comprises a plurality of first welding points (11), and the chip (4) comprises a plurality of second welding points (41).

3. A novel liquid conductive connection structure according to claim 2, characterized in that: The two ends of the conducting tube (2) correspond to the positions of the first welding point (11) and the second welding point (41).

4. A novel liquid conductive connection structure according to claim 3, characterized in that: The conducting liquid (5) connects the second welding point (41) and the first welding point (11).

5. A novel liquid conductive connection structure according to claim 1, characterized in that: The substrate (1) and the conducting tube (2) are bonded together by means of bonding glue (3).

6. A novel liquid conductive connection structure according to claim 1, characterized in that: The conducting tube (2) and the chip (4) are bonded together by means of an adhesive (3).

7. A novel liquid conductive connection structure according to claim 5 or 6, characterized in that: The adhesive (3) can be cured after low-temperature baking.

8. A method for manufacturing a novel liquid conductive connection structure according to claims 1 to 7, characterized in that: The specific steps are as follows: The adhesive (3) is evenly applied around the first solder joint (11) of the substrate (1); the conducting tube (2) is mounted on the substrate (1), the mounting position of the tube corresponds to the position of the first solder joint (11) of the substrate (1) one by one, and is fixed on the substrate (1) by the adhesive (3), and low-temperature baking is performed to solidify the adhesive (3); the adhesive (3) is applied to the top of the other side of the conducting tube (2); an appropriate amount of conducting liquid (5) is injected into each conducting tube (2); the chip (4) is mounted on the conducting tube (2), the applied adhesive (3) is in contact with the second solder joint (41) of the chip (4), and the adhesive (3) is solidified by secondary low-temperature baking, and the conducting liquid (5) connects the second solder joint (41) of the chip and the first solder joint (11) of the substrate to achieve conduction.

9. A method for manufacturing a novel liquid conductive connection structure according to claim 8, characterized in that: The adhesive (3) is evenly applied around the first welding point (11) and the second welding point (41) using an extremely fine needle.

10. The method for manufacturing a novel liquid conductive connection structure according to claim 9, characterized in that: By controlling the moving speed and flow rate of the needle, it is ensured that the coating thickness of the adhesive (3) is uniform and without omission.

Images