Double-sided heat dissipation module packaging structure of GaN chip

Abstract

The utility model provides a double-sided heat dissipation module packaging structure of a GaN chip, which belongs to the technical field of module packaging, and comprises a heat dissipation substrate, an upper heat conduction cover plate, a side wall support frame, a fixed pressing assembly and a heat conduction interface layer, the heat dissipation substrate is in a rectangular flat plate shape, and a groove is formed in the middle of the upper surface of the heat dissipation substrate and used for installing a GaN chip. The upper heat conduction cover plate is in a rectangular flat plate shape and is parallel to the heat dissipation substrate, a boss structure is arranged in the middle of the lower surface of the upper heat conduction cover plate, and the boss structure corresponds to a groove in the heat dissipation substrate; the side wall supporting frame surrounds the space between the heat dissipation substrate and the upper heat conduction cover plate to form a closed cavity. The fixing and pressing assembly comprises four studs and four pressing springs. According to the GaN chip packaging structure, the problem of low heat dissipation efficiency of the existing GaN chip packaging structure can be solved.

Description

TECHNICAL FIELD

[0001] The utility model belongs to module packaging technical field, concretely relates to a double -sided heat dissipation module packaging structure of GaN chip. BACKGROUND

[0002] With the rapid development of communication technology and power electronics technology, GaN chips have been widely used in 5G base stations, radar systems, electric vehicles and high-frequency power supplies due to their wide band gap, high saturation electron speed and high breakdown electric field and other excellent characteristics. However, GaN chips will generate a large amount of heat under high-frequency high-power working conditions, and the existing packaging structure mainly adopts single-sided heat dissipation design, that is, only the bottom of the chip is in contact with the heat dissipation substrate for heat conduction, and the upper surface is cooled by natural air convection. This single-sided heat dissipation structure has obvious shortcomings in high-power density application scenarios, and the heat is difficult to dissipate in time and effectively, resulting in rapid temperature rise of the chip, which seriously affects the working performance and reliability. Some improvement schemes try to use heat pipes or liquid cooling technology, but the system is complex, the cost is high and the reliability is low. Some other schemes use large-size heat sinks, but increase the packaging volume and weight, which is not suitable for space-limited application scenarios. In addition, the existing packaging structure generally has the problem of uneven heat distribution, which easily forms local hot spots, accelerates device aging and failure. Therefore, it is of great practical significance and application value to develop a high-efficiency double-sided heat dissipation GaN chip packaging structure.

[0003] The existing GaN chip packaging structure generally has the technical problems of low heat dissipation efficiency, uneven heat dissipation and difficulty in realizing double-sided heat dissipation, which leads to local overheating of GaN chips under high-power working conditions, seriously affecting the working performance and service life of the chips, especially in high-frequency high-power application scenarios, the existing single-sided heat dissipation structure cannot meet the growing heat dissipation demand. UTILITY MODEL CONTENTS

[0004] Therefore, the utility model provides a double -sided heat dissipation module packaging structure of GaN chip, can solve the problem of low heat dissipation efficiency of existing GaN chip packaging.

[0005] The utility model is realized as follows:

[0006] The utility model provides a kind of double-sided heat dissipation module packaging structure of GaN chip, wherein, including: heat dissipation substrate, upper heat conduction cover plate, side wall support frame, fixed compression assembly and heat conduction interface layer;The heat dissipation substrate is rectangular flat plate, recess is equipped with in upper surface middle part for installing GaN chip;The upper heat conduction cover plate is rectangular flat plate and is parallelly arranged with the heat dissipation substrate, the upper heat conduction cover plate lower surface middle part is equipped with boss structure, the boss structure corresponds with the recess on the heat dissipation substrate;The side wall support frame is enclosed cavity between the heat dissipation substrate and the upper heat conduction cover plate around;The fixed compression assembly includes four studs and four compression springs, the four studs are respectively located heat dissipation substrate four corners and vertically pass through the through-hole that the corresponding four corners of the upper heat conduction cover plate are opened, the four compression springs are sleeved on the four studs and are located the upper heat conduction cover plate upper surface, and the upper heat conduction cover plate is applied downwards by nut Pressure;The heat conduction interface layer is arranged between the boss structure lower surface and GaN chip upper surface, for improving heat conduction efficiency.

[0007] The utility model provides a kind of double-sided heat dissipation module packaging structure of GaN chip, wherein, including: heat dissipation substrate, upper heat conduction cover plate, side wall support frame, fixed compression assembly and heat conduction interface layer;The heat dissipation substrate is rectangular flat plate, recess is equipped with in upper surface middle part for installing GaN chip;The upper heat conduction cover plate is rectangular flat plate and is parallelly arranged with the heat dissipation substrate, the upper heat conduction cover plate lower surface middle part is equipped with boss structure, the boss structure corresponds with the recess on the heat dissipation substrate;The side wall support frame is enclosed cavity between the heat dissipation substrate and the upper heat conduction cover plate around;The fixed compression assembly includes four studs and four compression springs, the four studs are respectively located heat dissipation substrate four corners and vertically pass through the through-hole that the corresponding four corners of the upper heat conduction cover plate are opened, the four compression springs are sleeved on the four studs and are located the upper heat conduction cover plate upper surface, and the upper heat conduction cover plate is applied downwards by nut Pressure;The heat conduction interface layer is arranged between the boss structure lower surface and GaN chip upper surface, for improving heat conduction efficiency.

[0008] On the basis of above-mentioned technical scheme, a kind of double-sided heat dissipation module packaging structure of GaN chip of the utility model still can be made as follows improvement:

[0009] Wherein, the heat dissipation substrate is made of copper-based composite material, the thickness is 3 millimeters to 8 millimeters, the bottom surface of the heat dissipation substrate is equipped with a plurality of heat dissipation fins, the plurality of heat dissipation fins are parallelly arranged and extend along the length direction of heat dissipation substrate, the height of each heat dissipation fin is 5 millimeters to 15 millimeters, and the width is 1 millimeter to 3 millimeters.

[0010] The beneficial effect of the above improvement scheme is: the heat dissipation substrate made of copper-based composite material has excellent heat conduction performance, the thickness of 3 millimeters to 8 millimeters design ensures sufficient structural strength, and does not excessively increase module weight. The parallelly arranged heat dissipation fins arranged on the bottom surface significantly increase the heat dissipation area, and the height and width dimensions of the fins are optimized to ensure maximum heat dissipation efficiency in limited space, effectively accelerate the transfer of heat to the external environment, reduce the substrate temperature, and improve the overall heat dissipation performance.

[0011] Further, the upper heat-conducting cover plate is made of aluminum-based material, has a thickness of 2-5 mm, and is provided with a cross-shaped heat dissipation groove on the upper surface, the cross-shaped heat dissipation groove has a depth of 1-2 mm and a width of 3-6 mm; and the upper heat-conducting cover plate is provided with an annular protrusion around the edge of the upper surface, the annular protrusion has a height of 0.5-1 mm and a width of 2-4 mm.

[0012] The upper heat-conducting cover plate made of aluminum-based material has good heat-conducting performance and light weight, the cross-shaped heat dissipation groove increases the heat dissipation surface area, promotes air flow, and accelerates heat dissipation; the annular protrusion structure not only enhances the structural rigidity of the upper heat-conducting cover plate to prevent deformation under pressure, but also forms a guide air channel to enable hot air to flow along a specific path, avoiding heat accumulation in a local area and improving overall heat dissipation uniformity and efficiency.

[0013] Further, the side wall support frame includes four right-angle connecting blocks, each of which is installed at a corner of the heat dissipation base plate; each right-angle connecting block is made of high-temperature-resistant ceramic material and is provided with an L-shaped groove on the inner side, which cooperates with the edge of the heat dissipation base plate; and a vertical guide groove is arranged on the outer side wall of the right-angle connecting block, and the stud passes through the vertical guide groove and is fixedly connected with the heat dissipation base plate.

[0014] The four right-angle connecting blocks made of high-temperature-resistant ceramic material form a solid side wall support frame, effectively insulate heat and ensure structural stability; the L-shaped groove design enables the connecting block to tightly cooperate with the edge of the heat dissipation base plate, improving assembly accuracy and structural stability; and the vertical guide groove provides a fixed guide channel for the stud, ensuring that the stud maintains a vertical state during installation and disassembly, preventing uneven pressure caused by stud inclination, and ensuring uniform pressure distribution on the contact surface between the upper heat-conducting cover plate and the GaN chip.

[0015] Further, the boss structure is in a stepped shape, including a center boss and a peripheral boss surrounding the center boss; the center boss has a height of 0.8-1.5 mm and an area matching that of the GaN chip; the peripheral boss has a height of 0.3-0.8 mm and a width of 2-4 mm; and an annular transition slope is arranged between the center boss and the peripheral boss, and the annular transition slope has an inclination angle of 30-60 degrees.

[0016] The beneficial effects of the above improvement scheme are that the stepped boss structure on the lower surface of the upper heat-conducting cover plate realizes differential pressure distribution, the central boss directly contacts the GaN chip to ensure optimal heat conduction effect, and the peripheral boss maintains appropriate contact with the peripheral area of the chip to form a gradient heat conduction path. The annular transition slope design reduces stress concentration, smooths the heat flow channel, avoids structural deformation or damage caused by thermal stress, and increases the contact area, further improving the heat conduction efficiency.

[0017] Further, the grooves on the upper surface of the heat dissipation substrate are stepped, including a central groove and a peripheral groove surrounding the central groove; the depth of the central groove is 0.5-1 mm for placing the GaN chip; the depth of the peripheral groove is 0.2-0.5 mm and the width is 3-5 mm; an annular transition slope is provided between the central groove and the peripheral groove, and the inclination angle of the annular transition slope is 30-45 degrees.

[0018] The beneficial effects of the above improvement scheme are that the stepped groove design on the upper surface of the heat dissipation substrate enables the GaN chip to be precisely positioned and embedded, improving assembly accuracy. The central groove closely fits the bottom of the chip, and the peripheral groove provides a transition area for the heat conduction path. The annular transition slope reduces stress concentration points, allowing heat to spread more evenly from the chip to the heat dissipation substrate. The precise size design of the grooves meets the chip mounting requirements and maximizes the contact area, improving overall heat dissipation efficiency through optimized geometry.

[0019] Further, the heat-conducting interface layer is made of graphene composite material with a thickness of 0.1-0.3 mm, and the surface of the heat-conducting interface layer is provided with micron-level grid-shaped protrusions with a height of 0.01-0.05 mm and a spacing of 0.1-0.2 mm.

[0020] The beneficial effects of the above improvement scheme are that the graphene composite heat-conducting interface layer has extremely high thermal conductivity, significantly reducing contact thermal resistance. The micron-level grid-shaped protrusions on the surface increase the contact surface area and can fill small irregularities on the contact surface, eliminating contact gaps and air bubbles and reducing thermal resistance. The grid-shaped structure design ensures sufficient contact area while maintaining appropriate elastic deformation capability, allowing the heat-conducting interface layer to conform to irregular surfaces under pressure, ensuring the continuity and efficiency of heat conduction.

[0021] Further, the heat dissipation fins on the bottom surface of the heat dissipation substrate are in a wave shape structure, and a wave peak is provided every 5-10 mm along the length direction of the fin, with a height of 0.5-1 mm. The wave shape structure is used to increase the heat dissipation area.

[0022] The beneficial effects of the above improvement scheme are that the wavy structure design of the heat dissipation fin on the bottom surface of the heat dissipation substrate breaks the traditional linear heat dissipation fin air flow pattern, and the air flow disturbance formed by the wave crest enhances the heat exchange efficiency between air and the fin surface. The wavy structure not only increases the heat dissipation area, but also generates vortex flow when the air flows, destroys the boundary layer, improves the heat exchange efficiency, and at the same time enhances the structural strength of the fin, reduces the risk of deformation under high temperature conditions, and ensures the stability of the heat dissipation performance in long-term use.

[0023] Further, the cross-shaped heat dissipation grooves on the upper surface of the upper heat conduction cover plate are provided with circular heat dissipation holes at the intersection, the diameter of the circular heat dissipation hole is 5-8mm, and the depth is 1 / 2-2 / 3 of the thickness of the upper heat conduction cover plate; the bottom of the circular heat dissipation hole is provided with a radial micro-groove, the depth of the radial micro-groove is 0.2-0.5mm, and the width is 0.3-0.6mm.

[0024] The beneficial effects of the above improvement scheme are that the circular heat dissipation holes at the intersection of the cross-shaped heat dissipation grooves of the upper heat conduction cover plate form an additional heat dissipation channel of the heat accumulation area, and the radial micro-groove design further increases the heat dissipation surface area to form a micro air flow channel. This structure design promotes the diffusion of heat from the center to the periphery, accelerates the conduction speed of heat in the heat conduction cover plate, reduces the accumulation of heat in the center area, improves the heat dissipation uniformity, reduces the local hot spot temperature, and ensures the stable working environment of the GaN chip.

[0025] Further, the compression spring of the fixed compression assembly is a conical spring, the large end diameter of the conical spring is 8-12mm, the small end diameter is 4-6mm, and the height is 6-10mm; the large end of the conical spring is in contact with the upper surface of the upper heat conduction cover plate, and the small end of the conical spring is in contact with the nut; the elastic coefficient of the conical spring is 8-15N / mm.

[0026] The beneficial effects of the above improvement scheme are that the special geometric shape design of the conical spring has nonlinear elastic properties, which can provide a larger elastic force when the deformation is small to ensure sufficient compression force; when the deformation is large, the growth rate of the elastic force is reduced to prevent excessive compression damage to the device. The size and elastic coefficient of the spring are accurately calculated to ensure that the appropriate pressure is maintained when the structure expands or shrinks due to temperature changes, ensuring continuous good contact between the heat conduction interface layer and the GaN chip, and achieving stable heat dissipation performance in the full temperature range.

[0027] Compared with the prior art, the beneficial effects of the double-sided heat dissipation module packaging structure of the GaN chip are that: the double-sided heat dissipation module packaging structure of the GaN chip of the utility model forms upper and lower double-sided heat dissipation channels through the heat dissipation base plate and the upper heat conduction cover plate, and the recess and the boss structure are designed carefully, so that the heat of the chip can be efficiently conducted and dissipated in the upward and downward directions at the same time, and the limitation of single-sided heat dissipation in the prior art is effectively solved. In particular, by applying precise and uniform pressure through the fixed compression assembly, and by cooperating with the micron-level grid-shaped protrusion design of the heat conduction interface layer, the contact thermal resistance is significantly reduced, and the heat conduction efficiency is improved. The stepped design and the transition inclined surface structure reduce the thermal stress concentration and avoid structural damage caused by temperature changes. The copper-based composite heat dissipation base plate and the wave-shaped heat dissipation fin of the optimized design increase the heat dissipation area and improve the air convection heat exchange efficiency. The cross-shaped heat dissipation groove and the circular heat dissipation hole of the upper heat conduction cover plate form an efficient heat diffusion channel, and promote the uniform distribution of heat. By comprehensively using these technical measures, the heat dissipation efficiency of the GaN chip is significantly improved, the working temperature is reduced, and the service life is prolonged, and the utility model is especially suitable for high-frequency and high-power application scenarios, and meets the urgent needs of modern electronic equipment for high-performance heat dissipation systems. BRIEF DESCRIPTION OF DRAWINGS

[0028] In order to more clearly illustrate the technical scheme of the embodiments of the utility model, the following will briefly introduce the drawings needed to be used in the description of the embodiments of the utility model. Obviously, the drawings in the following description are only some embodiments of the utility model, and other drawings can be obtained by those skilled in the art without creating labor intensity.

[0029] Fig. 1 It is a sectional view of a double-sided heat dissipation module packaging structure of a GaN chip.

[0030] Fig. 2 It is a top view of a double-sided heat dissipation module packaging structure of a GaN chip.

[0031] In the drawings, the component list represented by each sign is as follows:

[0032] 10, heat dissipation base plate; 11, recess; 12, heat dissipation fin; 20, upper heat conduction cover plate; 21, boss structure; 22, cross-shaped heat dissipation groove; 30, side wall support frame; 31, right-angle connecting block; 40, fixed compression assembly; 41, stud; 42, compression spring; 50, heat conduction interface layer; 60, closed cavity. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme of the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application.

[0034] As Figs. 1-2 An embodiment of a double-sided heat dissipation module packaging structure of a GaN chip is provided, and in the embodiment, the double-sided heat dissipation module packaging structure of the GaN chip comprises a heat dissipation substrate 10, an upper heat conduction cover plate 20, a side wall support frame 30, a fixing and pressing assembly 40 and a heat conduction interface layer 50; the heat dissipation substrate is in a rectangular flat plate shape, and a recess 11 is arranged in the middle of the upper surface of the heat dissipation substrate for mounting the GaN chip; the upper heat conduction cover plate is in a rectangular flat plate shape and is arranged in parallel with the heat dissipation substrate, and a boss structure is arranged in the middle of the lower surface of the upper heat conduction cover plate, and the boss structure corresponds to the recess on the heat dissipation substrate; the side wall support frame is arranged around the heat dissipation substrate and the upper heat conduction cover plate to form a closed cavity 60; the fixing and pressing assembly comprises four threaded studs 41 and four pressing springs 42, the four threaded studs are respectively arranged at the four corners of the heat dissipation substrate and vertically pass through through holes arranged at the corresponding four corners of the upper heat conduction cover plate, the four pressing springs are sleeved on the four threaded studs and arranged on the upper surface of the upper heat conduction cover plate, and the upper heat conduction cover plate is subjected to downward pressure by the nuts; the heat conduction interface layer is arranged between the lower surface of the boss structure and the upper surface of the GaN chip, and is used for improving the heat conduction efficiency.

[0035] In the above technical scheme, the heat dissipation substrate is made of copper-based composite material, and has a thickness of 3-8 mm; a plurality of heat dissipation fins 12 are arranged on the bottom surface of the heat dissipation substrate, the plurality of heat dissipation fins are arranged in parallel and extend along the length direction of the heat dissipation substrate, each heat dissipation fin has a height of 5-15 mm and a width of 1-3 mm.

[0036] Further, in the above technical scheme, the upper heat conduction cover plate is made of aluminum-based material and has a thickness of 2-5 mm; a cross-shaped heat dissipation groove 22 is arranged on the upper surface of the upper heat conduction cover plate, the cross-shaped heat dissipation groove has a depth of 1-2 mm and a width of 3-6 mm; a ring-shaped protrusion is arranged at the edge of the upper surface of the upper heat conduction cover plate, the ring-shaped protrusion has a height of 0.5-1 mm and a width of 2-4 mm.

[0037] Further, in the above technical scheme, the side wall support frame comprises four right-angle connecting blocks 31, each right-angle connecting block is arranged at a corner of the heat dissipation substrate; each right-angle connecting block is made of high-temperature-resistant ceramic material, and an L-shaped recess is arranged on the inner side of each right-angle connecting block, the L-shaped recess is matched with the edge of the heat dissipation substrate; a vertical guide groove is arranged on the outer side wall of each right-angle connecting block, and the threaded stud is fixedly connected with the heat dissipation substrate through the vertical guide groove.

[0038] Further, in the above technical solution, the boss structure 21 is in a stepped shape, including a center boss and a peripheral boss surrounding the center boss; the height of the center boss is 0.8-1.5 mm, and the area matches the area of the GaN chip; the height of the peripheral boss is 0.3-0.8 mm, and the width is 2-4 mm; an annular transition slope is arranged between the center boss and the peripheral boss, and the inclination angle of the annular transition slope is 30-60 degrees.

[0039] Further, in the above technical solution, the groove on the upper surface of the heat dissipation substrate is in a stepped shape, including a center groove and a peripheral groove surrounding the center groove; the depth of the center groove is 0.5-1 mm, and the center groove is used for placing the GaN chip; the depth of the peripheral groove is 0.2-0.5 mm, and the width is 3-5 mm; an annular transition slope is arranged between the center groove and the peripheral groove, and the inclination angle of the annular transition slope is 30-45 degrees.

[0040] Further, in the above technical solution, the heat-conducting interface layer 50 is made of graphene composite material, and the thickness is 0.1-0.3 mm; the surface of the heat-conducting interface layer is provided with a micro-grid-shaped protrusion, the height of the micro-grid-shaped protrusion is 0.01-0.05 mm, and the distance between the micro-grid-shaped protrusions is 0.1-0.2 mm.

[0041] Further, in the above technical solution, the heat dissipation fins on the bottom surface of the heat dissipation substrate are in a wave-shaped structure, and a wave peak is arranged every 5-10 mm along the length direction of the fin; the height of the wave peak is 0.5-1 mm, and the wave-shaped structure is used for increasing the heat dissipation area.

[0042] Further, in the above technical solution, a circular heat dissipation hole is arranged at the intersection of the cross-shaped heat dissipation groove on the upper surface of the upper heat-conducting cover plate; the diameter of the circular heat dissipation hole is 5-8 mm, and the depth is 1 / 2-2 / 3 of the thickness of the upper heat-conducting cover plate; a radial micro-groove is arranged at the bottom of the circular heat dissipation hole, and the depth of the radial micro-groove is 0.2-0.5 mm, and the width is 0.3-0.6 mm.

[0043] Further, in the above technical solution, the compression spring for fixing the compression assembly is a conical spring; the diameter of the large end of the conical spring is 8-12 mm, the diameter of the small end is 4-6 mm, and the height is 6-10 mm; the large end of the conical spring is in contact with the upper surface of the upper heat-conducting cover plate, and the small end is in contact with the nut; the elastic coefficient of the conical spring is 8-15 N / mm.

[0044] When the GaN chip double-sided heat dissipation module packaging structure of the utility model is used, firstly, the GaN chip is placed in the center groove on the upper surface of the heat dissipation substrate, ensuring that the chip is completely embedded in the groove and in flat contact with the bottom of the groove. Then, the upper surface of the GaN chip is covered with a heat-conducting interface layer, ensuring that the micron-level grid-shaped convex surface faces downward and is in contact with the surface of the chip. Next, the four right-angle connecting blocks are fixedly connected with the edge of the heat dissipation substrate through the L-shaped grooves, forming a side wall support frame. Subsequently, the upper heat-conducting cover plate is placed above the side wall support frame, with the boss structure facing the heat-conducting interface layer above the GaN chip. Four studs are passed through the four corner through holes of the upper heat-conducting cover plate and are fixedly connected with the heat dissipation substrate. A conical spring is sleeved on the stud, with the large end of the spring in contact with the upper surface of the upper heat-conducting cover plate and the small end facing upward. Finally, nuts are installed on the top end of the stud and are uniformly tightened, so that the conical spring generates appropriate pressure, ensuring that the boss structure of the upper heat-conducting cover plate is in close contact with the GaN chip through the heat-conducting interface layer. After installation is completed, the tightening degree of the nuts can be adjusted to accurately control the pressing force, so as to obtain the best heat conduction effect. During use, heat is dissipated outward through the upper heat-conducting cover plate and the heat dissipation substrate, realizing double-sided high-efficiency heat dissipation and ensuring stable operation of the GaN chip under high-power working conditions.

[0045] A specific embodiment of the utility model is provided below:

[0046] The GaN chip double-sided heat dissipation module packaging structure in the embodiment mainly includes five parts: a heat dissipation substrate, an upper heat-conducting cover plate, a side wall support frame, a fixed pressing assembly and a heat-conducting interface layer. The heat dissipation substrate is made of copper-tungsten alloy material and has a square plate structure with a size of 40 mm x 40 mm x 5 mm, a heat conductivity coefficient of 380 W / (m·K), an upper surface with a center groove with a depth of 0.8 mm and a size of 6 mm x 6 mm for installing the GaN chip, a peripheral groove with a depth of 0.3 mm and a width of 4 mm around the center groove, and an annular transition slope with an inclination angle of 40 degrees connecting the two grooves. The bottom surface of the heat dissipation substrate is provided with 16 wave-shaped heat dissipation fins arranged in parallel, each fin having a length of 40 mm, a height of 10 mm and a width of 2 mm, and a wave-shaped structure having a wave peak with a height of 0.8 mm every 8 mm.

[0047] The upper heat-conducting cover plate is made of high-purity aluminum material, with a size of 42 mm x 42 mm x 3 mm and a heat conductivity of 210 W / (m·K). The lower central surface is provided with a stepped boss structure including a central boss and a peripheral boss. The central boss has a size of 6 mm x 6 mm and a height of 1.2 mm. The peripheral boss has a width of 3 mm and a height of 0.5 mm, and the two bosses are connected by an annular transition slope with an inclination angle of 45 degrees. The upper surface of the upper heat-conducting cover plate is provided with a cross-shaped heat dissipation groove with a depth of 1.5 mm and a width of 4 mm, and a circular heat dissipation hole with a diameter of 6 mm and a depth of 2 mm is arranged at the intersection of the cross-shaped heat dissipation groove. The bottom of the heat dissipation hole is provided with 16 equidistantly distributed radial micro-grooves with a depth of 0.3 mm and a width of 0.5 mm.

[0048] The side wall support frame is composed of four right-angle connecting blocks made of aluminum nitride ceramic material. Each connecting block has a height of 6 mm, an L-shaped groove matching the edge of the heat dissipation substrate is arranged on the inner side, and a vertical guide groove with a width of 3 mm and a depth of 2 mm is arranged on the outer side. The fixed compression assembly includes four stainless steel studs with a diameter of 5 mm and four conical springs made of high-elasticity alloy material. The large end of the conical spring has a diameter of 10 mm, the small end has a diameter of 5 mm, the height is 8 mm, and the elastic coefficient is 12 N / mm.

[0049] The heat-conducting interface layer is made of graphene and nano-silver composite material, with a thickness of 0.2 mm and a heat conductivity of up to 1800 W / (m·K). The surface is provided with micron-level grid-shaped protrusions with a height of 0.03 mm and a pitch of 0.15 mm. In actual application, the packaging structure can reduce the maximum working temperature of the GaN chip from 175℃ of the traditional single-sided heat dissipation structure to 125℃, and the thermal resistance is reduced by 46% compared with the traditional packaging structure, significantly improving the power carrying capacity and reliability of the GaN chip, and being particularly suitable for high-power density application scenarios such as 5G base station power amplifiers and high-frequency radar systems.

[0050] Specifically, the principle of the utility model is: the utility model is based on the basic principle of heat conduction and heat convection, and a bidirectional heat conduction channel is innovatively constructed to realize multidimensional diffusion and emission of heat. Firstly, the heat dissipation substrate is in direct contact with the bottom of the GaN chip to form a downward heat conduction channel, and a large amount of heat is rapidly conducted to the heat dissipation substrate through the close contact of the heat conduction interface layer and then emitted to the environment through the wave-shaped heat dissipation fins at the bottom. At the same time, the upper heat conduction cover plate is in contact with the upper surface of the GaN chip through the boss structure to form an upward heat conduction channel, so that the heat generated on the upper surface of the chip can be efficiently transmitted to the upper heat conduction cover plate and then emitted outward through the cross-shaped heat dissipation grooves and the circular heat dissipation holes. The uniform pressure applied by the fixing and pressing assembly through the spring ensures the close fit between the contact surfaces and minimizes the contact thermal resistance. The micron-level grid-shaped protrusions of the heat conduction interface layer can fill the small uneven areas of the contact surface, further reducing the thermal resistance. The stepped groove and boss design creates a gradient heat flow path, so that the heat can be more evenly diffused to avoid the formation of hot spots. In addition, the sidewall support frame is made of high-temperature-resistant ceramic material, which not only provides structural support but also effectively isolates the lateral heat loss, thereby strengthening the efficiency of bidirectional heat dissipation. This multidimensional heat management strategy significantly improves the heat conduction and emission efficiency and fundamentally solves the heat dissipation problem of the GaN chip during high-power operation.

[0051] The above merely describes the specific implementation of the utility model, but the protection scope of the utility model is not limited to this. Any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the utility model, which should be covered within the protection scope of the utility model. Therefore, the protection scope of the utility model should be subject to the protection scope of the claims.

Claims

1. A double-sided heat dissipation module packaging structure for a GaN chip, characterized in that, include: The system comprises a heat dissipation substrate, an upper thermally conductive cover plate, a sidewall support frame, a fixing and clamping assembly, and a thermally conductive interface layer. The heat dissipation substrate is a rectangular flat plate with a groove in the center of its upper surface for mounting a GaN chip. The upper thermally conductive cover plate is also a rectangular flat plate and is parallel to the heat dissipation substrate. A boss structure is located in the center of the lower surface of the upper thermally conductive cover plate, and the boss structure corresponds to the groove on the heat dissipation substrate. The sidewall support frame surrounds the heat dissipation substrate and the upper thermally conductive cover plate to form a closed cavity. The fixing and clamping assembly includes four studs and four clamping springs. The four studs are located at the four corners of the heat dissipation substrate and pass vertically through through holes opened at the corresponding four corners of the upper thermally conductive cover plate. The four clamping springs are sleeved on the four studs and located on the upper surface of the upper thermally conductive cover plate, and apply downward pressure to the upper thermally conductive cover plate through nuts. The thermally conductive interface layer is disposed between the lower surface of the boss structure and the upper surface of the GaN chip to improve heat conduction efficiency.

2. The double-sided heat dissipation module packaging structure for a GaN chip according to claim 1, characterized in that, The heat dissipation substrate is made of copper-based composite material with a thickness of 3 mm to 8 mm. The bottom surface of the heat dissipation substrate is provided with multiple heat dissipation fins, which are arranged in parallel and extend along the length of the heat dissipation substrate. Each heat dissipation fin has a height of 5 mm to 15 mm and a width of 1 mm to 3 mm.

3. The double-sided heat dissipation module packaging structure for a GaN chip according to claim 2, characterized in that, The upper heat-conducting cover is made of aluminum-based material with a thickness of 2 mm to 5 mm. The upper surface of the upper heat-conducting cover is provided with a cross-shaped heat dissipation groove with a depth of 1 mm to 2 mm and a width of 3 mm to 6 mm. The upper surface of the upper heat-conducting cover is provided with annular protrusions at the four edges, with a height of 0.5 mm to 1 mm and a width of 2 mm to 4 mm.

4. The double-sided heat dissipation module packaging structure for a GaN chip according to claim 3, characterized in that, The sidewall support frame includes four right-angle connecting blocks, each of which is installed at one of the four corners of the heat dissipation substrate. The right-angle connecting blocks are made of high-temperature resistant ceramic material, and each right-angle connecting block has an L-shaped groove on its inner side, which matches the edge of the heat dissipation substrate. The outer side wall of the right-angle connecting block has a vertical guide groove, and the stud passes through the vertical guide groove and is fixedly connected to the heat dissipation substrate.

5. The double-sided heat dissipation module packaging structure for a GaN chip according to claim 4, characterized in that, The boss structure is stepped, including a central boss and peripheral bosses surrounding the central boss; the central boss has a height of 0.8 mm to 1.5 mm and an area matching the area of ​​the GaN chip; the peripheral bosses have a height of 0.3 mm to 0.8 mm and a width of 2 mm to 4 mm; an annular transition slope is provided between the central boss and the peripheral bosses, and the annular transition slope has an inclination angle of 30 degrees to 60 degrees.

6. The double-sided heat dissipation module packaging structure for a GaN chip according to claim 5, characterized in that, The grooves on the upper surface of the heat dissipation substrate are stepped, including a central groove and peripheral grooves surrounding the central groove; the central groove has a depth of 0.5 mm to 1 mm and is used to place the GaN chip; the peripheral groove has a depth of 0.2 mm to 0.5 mm and a width of 3 mm to 5 mm; an annular transition slope is provided between the central groove and the peripheral groove, and the annular transition slope has an inclination angle of 30 degrees to 45 degrees.

7. The double-sided heat dissipation module packaging structure for a GaN chip according to claim 6, characterized in that, The thermally conductive interface layer is made of graphene composite material with a thickness of 0.1 mm to 0.3 mm. The surface of the thermally conductive interface layer is provided with micron-sized mesh-like protrusions with a height of 0.01 mm to 0.05 mm and a spacing of 0.1 mm to 0.2 mm between the micron-sized mesh-like protrusions.

8. The double-sided heat dissipation module packaging structure for a GaN chip according to claim 7, characterized in that, The heat dissipation fins on the bottom surface of the heat dissipation substrate have a wavy structure. The wavy structure has a peak every 5 to 10 millimeters along the length of the fins, and the peak height is 0.5 to 1 millimeter. The wavy structure is used to increase the heat dissipation area.

9. The double-sided heat dissipation module packaging structure for a GaN chip according to claim 8, characterized in that, A circular heat dissipation hole is provided at the intersection of the cross-shaped heat dissipation grooves on the upper surface of the heat-conducting cover plate. The diameter of the circular heat dissipation hole is 5 mm to 8 mm, and the depth is 1 / 2 to 2 / 3 of the thickness of the upper heat-conducting cover plate. A radial micro-groove is provided at the bottom of the circular heat dissipation hole. The depth of the radial micro-groove is 0.2 mm to 0.5 mm, and the width is 0.3 mm to 0.6 mm.

10. The double-sided heat dissipation module packaging structure for a GaN chip according to claim 9, characterized in that, The clamping spring of the fixed clamping assembly is a conical spring, the large end of which has a diameter of 8 mm to 12 mm, the small end of which has a diameter of 4 mm to 6 mm, and a height of 6 mm to 10 mm; the large end of the conical spring contacts the upper surface of the upper heat-conducting cover plate, and the small end of the conical spring contacts the nut; the elastic coefficient of the conical spring is 8 N / mm to 15 N / mm.

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