Heat dissipation structure based on combination of glass substrate chip vertical interconnection and liquid metal shielding cover

Abstract

The invention discloses a heat dissipation structure based on combination of vertical interconnection of a glass substrate chip and a liquid metal shielding case, the structure is mainly composed of a glass substrate (1), a heat source chip (2), the liquid metal shielding case (3), a metal heat conduction rod (4), a micro-channel (5) and a TGV through hole (8), and the TGV refers to a three-dimensional interconnection (TGV) technology based on glass through hole manufacturing. A heat dissipation structure based on combination of glass substrate chip vertical interconnection and a liquid metal shielding cover is mainly characterized in that a heat source chip (2) is vertically interconnected on a glass substrate (1) through a TGV technology, the liquid metal shielding cover (3) is installed on the heat source chip (2), and heat conduction silicone grease needs to be filled between the heat source chip and the liquid metal shielding cover to reduce heat resistance. A cavity for containing liquid metal (3) is formed in the liquid metal shielding cover, electromagnetic signals can be shielded, efficient heat dissipation of the heat source chip (2) can be achieved, the metal heat conduction rods (4) are machined through the metalized TGV through holes, effective heat transfer can be conducted on the liquid metal, heat exchange media in the micro-channels (5) in the glass substrate can conduct convective heat exchange on the metal heat conduction rods, and the heat conduction efficiency of the heat source chip (2) is improved. Heat generated by the heat source chip (2) is effectively conducted. The temperature of the heat source chip can be obviously reduced, the low heat dissipation efficiency caused by the low heat conductivity of the glass substrate is improved, the main heat conduction process comprises the heat source chip (2), the liquid metal shielding cover (3), the metal heat conduction rod (4), the internal heat exchange medium of the micro-channel (5) and the outside, the temperature distribution of the structure in the vertical direction is effectively improved, and the heat dissipation efficiency is improved. The heat dissipation limit of the structure is improved, and the service life of the chip is prolonged. The heat dissipation structure is compact in structure, space-saving and good in heat dissipation capability, is an efficient heat dissipation structure, and has a better application prospect in the heat dissipation field of high-heating chips.

Description

Technical Field

[0001] The present invention belongs to the field of heat dissipation of high-power electronic devices, and specifically relates to a heat dissipation structure based on vertical interconnection of glass substrate chips combined with a liquid metal shielding cover. The heat dissipation structure is particularly suitable for heat dissipation conditions of high-power electronic devices using glass substrates that require shielding against electromagnetic signal interference. Background Art

[0002] Current semiconductor manufacturing processes primarily utilize advanced three-dimensional packaging integration technology, utilizing vertical through-hole structures to stack multiple chips vertically. Through-silicon vias (TSVs) and through-glass vias (TGVs) are currently the two most commonly used through-hole interconnect methods. The key advantages of using glass substrates for chip interconnection in 3D integrated electronic packaging include excellent dielectric properties, thermomechanical stability, and suitability for high-density integration. Its highly matched thermal expansion coefficient with silicon chips significantly reduces thermal cycling stress and prevents solder joint fatigue failure, making it a key material for high-frequency, high-density packaging in the 5G era.

[0003] The rapid development of the electronic information industry is driving the evolution of electronic components toward thinness, miniaturization, high power consumption, and high integration. This transformation significantly increases heat dissipation challenges. A major drawback of packaging high-heat-generating chips on glass substrates is their low thermal conductivity (1-2 W / m·K), far lower than that of metal or ceramic materials. This results in inefficient heat transfer and makes it difficult to meet the cooling requirements of high-power chips.

[0004] Excessive heat accumulation not only seriously affects product performance and user experience, but may also cause equipment failure, damage, and even safety accidents, posing a major risk.

[0005] Therefore, in high heat flux density applications, glass substrates usually need to be combined with other heat dissipation technologies to compensate for their insufficient heat dissipation performance.

[0006] To solve the above heat dissipation problems, the present invention aims to propose a heat dissipation structure based on vertical interconnection of glass substrate chips combined with a liquid metal shielding cover. By combining liquid metal shielding cover, metal thermal conductive rods and microfluidic channels with multiple heat dissipation technologies, the heat dissipation efficiency of glass substrates as chip interconnections is improved, heat accumulation is improved, and the heat dissipation limit is increased. Summary of the Invention

[0007] In response to the current heat dissipation problem of vertical chip interconnection based on glass substrate, the present invention proposes a heat dissipation structure based on vertical chip interconnection on glass substrate combined with liquid metal shielding cover, including: glass substrate, heat source chip, liquid metal shielding cover, metal thermal conductive rod, and microchannel.

[0008] The heat source chip is vertically interconnected on a glass substrate using TGV technology. The liquid metal shield, installed on the heat source chip, can shield electromagnetic signal interference and ensure device safety. Its high thermal conductivity can also effectively absorb the heat generated by the heat source chip. The liquid metal shield cannot directly contact the heat source chip and needs to be filled with thermal grease on the heat source chip surface for efficient heat transfer. The liquid metal shield should be at least 0.1mm away from the heat source chip and should be an integrated package to prevent leakage of the internal liquid metal.

[0009] Optionally, the metal thermally conductive rod is generally processed before the liquid metal shielding cover. The metal thermally conductive rod extends from the bottom of the glass substrate to the bottom of the liquid metal shielding cover, and directly contacts the liquid metal shielding cover to dissipate heat. The material of the metal thermally conductive rod can be selected from metals with low thermal expansion coefficients, such as titanium alloy and Invar, to avoid the glass from shattering due to thermal expansion of the metal.

[0010] Optionally, the microchannel is mainly used to take away the heat of the metal thermal rod, and the heat exchange medium uses nanofluid or deionized water as the main part for heat exchange with the outside world. The design of the microchannel needs to avoid the metal thermal rod to ensure that the error generated when the metallized TGV through-hole manufactures the metal thermal rod is reduced to reduce processing difficulties.

[0011] Based on TGV technology, the holes under the heat source chip need to be made into through holes for vertical interconnection.

[0012] The present invention adopts the above technical solution, which has the following beneficial effects:

[0013] Compared with silicon substrates, glass-based chip packaging structures have the following advantages: glass has a low dielectric constant and low dielectric loss, which can significantly reduce signal transmission delay and energy loss, making it suitable for high-frequency and high-performance computing scenarios. The thermal expansion coefficient of glass is close to that of silicon, which can effectively reduce thermal stress and improve packaging reliability. Glass material is low-cost, has a high surface flatness, and a simple processing process. Glass has good chemical stability and airtightness, which can protect chips from environmental corrosion.

[0014] The liquid metal shield's electromagnetic signal shielding reduces electromagnetic interference and device collisions. Its high thermal conductivity effectively absorbs heat generated by the chip and transfers it to the heat transfer medium within the microchannel via a metal heat-conducting rod. The primary heat transfer process is: heat source chip - liquid metal shield - metal heat-conducting rod - heat transfer medium within the microchannel - to the outside world. This structure compensates for the heat accumulation disadvantage caused by the inherent low thermal conductivity of glass, significantly improving heat dissipation efficiency and heat dissipation limit, and extending the device's lifespan. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 Schematic diagram of the overall structure of an embodiment of the present invention; Figure 2 A front view of an embodiment of the present invention; Figure 3 Schematic diagram of the glass substrate structure according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the liquid metal shielding cover and chip installation structure according to an embodiment of the present invention; Figure 5 Schematic diagram of a metal heat conducting rod according to an embodiment of the present invention.

[0016] Specific implementation method.

[0017] In order to clearly illustrate the specific structure, purpose of the invention, technical solutions and advantages of the present invention, the present invention is further described in detail. If this description involves specific examples, it is only used to explain the present invention and does not limit the present invention. Other people based on this embodiment shall fall within the scope of protection of the present invention if they do not make an inventive embodiment.

[0018] A heat dissipation structure based on vertical interconnection of glass substrate chips combined with liquid metal shielding cover, such as Figure 1 As shown, the structure mainly consists of a glass substrate (1), a heat source chip (2), a liquid metal shielding cover (3), a metal heat conducting rod (4), and a microchannel (5).

[0019] The heat source chips are vertically interconnected on a glass substrate using TGV technology. A liquid metal shield is installed around the heat source chips, maintaining a minimum spacing of 0.1mm from the chips. Excessive spacing is not recommended, as this will reduce shielding capabilities and overall heat dissipation efficiency. Before installing the liquid metal shield, thermal grease should be applied to the top surface of the heat source chips (2-1) to fill gaps and reduce thermal resistance, thereby improving heat dissipation efficiency. Strip-shaped openings (3-1) are machined around the liquid metal shield to prevent resonance interference with the chips. This also allows for some flexibility during thermal expansion and contraction, effectively alleviating thermal stress and ensuring the stability and reliability of the shield and internal components. In practice, design should be tailored to the actual operating dimensions.

[0020] TGV through-holes realize vertical interconnection of devices. TGV through-holes used for device interconnection require a series of processing before they can be used, such as the production of seed layers and metallization of holes.

[0021] like Figure 2 As shown, the metal thermally conductive rod is in contact with the bottom of the liquid metal shielding cover. Heat can be transferred more efficiently through contact heat transfer to reduce the temperature. The metal thermally conductive rod needs to be made through a metallization filling process, and the production of the metal thermally conductive rod must be completed before the installation step of the liquid metal shielding cover to ensure the molding of the metal thermally conductive rod. The liquid metal in the liquid metal shielding cover can be injected through the opening on the top of the glass substrate using the pressure difference method.

[0022] like Figure 3 The figure shows the structure of the glass substrate. The through holes are made using TGV technology. The internal flow channel is provided with fins 5-1 to increase the heat dissipation area and further improve the heat dissipation performance. The design of the microchannel needs to avoid the TGV through hole, that is, the heat exchange medium cannot communicate with the chip interconnection structure and the metal heat conducting rod. According to the specific working conditions, the shape of the microchannel can be changed or pin fins can be added to break the fluid boundary layer, form local turbulence, promote the mixing of the heat exchange medium, and enhance heat dissipation. The heat exchange medium in the microchannel enters through the inlet (6) and flows out through the outlet (7), transferring the heat of the metal heat conducting rod to the outside world, forming the main heat conduction process: heat source chip - liquid metal shield - metal heat conducting rod - heat exchange medium in the microchannel - outside world. The heat dissipation efficiency of this structure is high. The lack of any heat transfer process will lead to heat accumulation and overall temperature rise. Therefore, this structure can ensure that the heat generated by the heat source chip is effectively transferred to the outside world, increasing the service life of the device and saving costs.

[0023] The above description is only a preferred embodiment of the present invention and should not be used to limit the scope of implementation of the present invention. In other words, simple equivalent changes and modifications made according to the scope of the patent application and the description of the present invention are still within the scope of the present patent.

Claims

1. A heat dissipation structure based on vertically interconnected glass substrate chips combined with a liquid metal shield, comprising a glass substrate, a heat source chip, a liquid metal shield, a metal heat conducting rod made of metallized TGV vias, and microchannels. The liquid metal shield is mounted on the heat source chip, and the metal heat conducting rod is machined from the bottom surface of the glass substrate, contacting the liquid metal shield for heat dissipation. Microchannels are machined around the metal heat conducting rod to remove heat from the rod through convection.

2. The heat dissipation structure based on vertical interconnection of glass substrate chips combined with a liquid metal shield according to claim 1, characterized in that: The liquid metal shield must not directly contact the heat source chip, requiring a minimum spacing of 0.1 mm. Strip-shaped openings are machined around the shield to prevent deformation caused by thermal or mechanical stress, which also aids in electromagnetic signal shielding. The size of the liquid metal shield depends on the size of the heat source chip. Because of its high thermal conductivity, chemical stability and high boiling point, liquid metal can isolate electromagnetic signals and dissipate the heat generated by the heat source chip to the liquid metal shielding cover through conduction. It has high heat dissipation efficiency and does not hinder the vertical interconnection of the chip.

3. The heat dissipation structure based on vertical interconnection of glass substrate chips combined with a liquid metal shield according to claim 1, characterized in that: The metal heat conducting rod passes through the glass substrate and is in direct contact with the liquid metal for heat dissipation. The metal heat conducting rod is made of metal with high thermal conductivity and can effectively conduct heat to the microchannel. The metal heat conducting rod has uniform size and length, and the number and position are determined according to the liquid metal shielding cover, so that the overall heat dissipation efficiency is as high as possible.

4. The heat dissipation structure based on vertical interconnection of glass substrate chips combined with a liquid metal shield according to claim 1, characterized in that: The liquid metal material is gallium-based liquid metal or indium-based liquid metal, and the microchannel cooling medium is nanofluid or deionized water.

5. The heat dissipation structure based on vertical interconnection of glass substrate chips combined with a liquid metal shield according to claim 1, characterized in that: The substrate can be made of LTCC, HTCC, or silicon. The higher the thermal conductivity of the substrate, the more significant the heat dissipation effect of the structure.

Images