Transistor with uniform heat dissipation and use method

Abstract

The invention discloses a transistor uniform in heat dissipation and a using method, and relates to the technical field of semiconductor devices.The transistor uniform in heat dissipation comprises a transistor body, a heat dissipation base and a composite heat dissipation laminated body, the composite heat dissipation laminated body comprises copper layers and graphene layers, and the copper layers and the graphene layers are staggered, stacked and embedded into the inner wall of a gradient heat dissipation groove; the thickness of the copper layer is set to be 50-80 microns, and the thickness of the graphene layer is set to be 10-20 microns. Through the composite heat dissipation laminated body, directional diffusion of heat from the center to the edge is achieved, the problem of uneven heat dissipation caused by anisotropy of homogeneous materials is solved, the temperature distribution uniformity of the transistor body is improved, and local overheating failure is effectively avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor devices, and specifically to a transistor with uniform heat dissipation and its usage method. Background Art

[0002] With the development of electronic devices towards high integration and low power consumption, the heat dissipation problem of transistors, as core components, has become increasingly prominent. A transistor is an electronic device based on semiconductor materials, mainly used for amplifying, switching, or regulating electronic signals, and is one of the core components of modern electronic circuits. The heat dissipation of existing transistors mainly relies on external heat sinks, fans, or liquid cooling systems, which often leads to a large temperature gradient on the transistor surface, and hot spots are prone to accelerating device aging and reducing reliability.

[0003] Therefore, it is very necessary for this application to propose a transistor with uniform heat dissipation and its usage method to solve the problems in the background.

[0004] Patent CN103378140B discloses an insulated gate bipolar transistor. The above patent achieves avoiding overlay errors, ensuring the consistency of cell channels, and improving dynamic characteristics; at the same time, it can save one lithography mask, reduce process steps, and save costs.

[0005] In the above patent, by optimizing the cell channel structure design and simplifying the lithography process, overlay errors and dynamic characteristics are effectively solved. However, its technical solution focuses on manufacturing process and electrical performance optimization, and does not involve the core problem of thermal management under high-power conditions, especially the risk of thermal failure caused by local hot spot accumulation, transient thermal shock response lag, and interface thermal resistance superposition due to the anisotropy of the heat dissipation path when the transistor operates under continuous large current.

[0006] For this reason, this application proposes a transistor with uniform heat dissipation and its usage method that can achieve the construction of a directional heat diffusion network through a copper / graphene gradient laminate and variable cross-section heat dissipation grooves, combined with the dynamic heat dissipation area adjustment of a shape memory alloy-driven retractable heat sink and the reduction of multi-dimensional contact thermal resistance by cooperating with a vertical array of waveform interface carbon nanotubes. Summary of the Invention

[0007] The purpose of the present invention is to provide a transistor with uniform heat dissipation and its usage method to solve the technical problem in the above background art that the heat dissipation of transistors mainly relies on external heat sinks, fans, or liquid cooling systems, resulting in a large temperature gradient on the transistor surface and hot spots being prone to accelerating device aging.

[0008] To achieve the above purpose, the present invention provides the following technical solution: A transistor with uniform heat dissipation, comprising a transistor body, a heat dissipation base, and a composite heat dissipation laminate. The bottom end of the outer wall of the transistor body is attached to the heat dissipation base through a thermal interface material; The composite heat dissipation laminate includes a copper layer and a graphene layer. The copper layer and the graphene layer are alternately stacked and embedded in the inner wall of the gradient heat dissipation groove. The thickness of the copper layer is set to be 50 - 80 μm, and the thickness of the graphene layer is set to be 10 - 20 μm.

[0009] Preferably, the gradient heat dissipation groove extends from the center of the top of the outer wall of the transistor body to both sides. The heat dissipation partition includes a heat conduction column, a support plate, and a diversion fin. The bottom surface of the support plate is welded to the top of the outer wall of the heat conduction column. The bottom of the heat conduction column is vertically embedded in the top of the transistor body. The diversion fin is fixedly installed on the top surface of the support plate at an inclination of 45°. The main fin of the diversion fin is set in an inverted V shape. There are reinforcing ribs at the end of the main fin. There are split fins extending from both sides of the top of the main fin, and hemispherical protrusions are provided at the ends of the split fins. The depth of the gradient heat dissipation groove gradually decreases from 0.3 - 0.5 mm in the central region to 0.1 - 0.2 mm at the edge, and the width of the groove expands from 1.0 - 1.5 mm in the center to 2.0 - 2.5 mm at the edge.

[0010] Preferably, each layer of the copper layer and the graphene layer is bonded by a high - thermal - conductivity adhesive, and the high - thermal - conductivity adhesive is filled in the troughs of the corrugated contact surface. A distributed temperature heat conductor is buried inside the transistor body. The distributed temperature heat conductor is distributed in a grid along the PN - junction region of the transistor body. The distributed temperature heat conductor is connected to an external control unit through micro - wires. The side of the outer wall of the heat dissipation base is rigidly connected to a coupling mechanism. The coupling mechanism includes a slot and a boss. The slots are arrayed on the bottom surface of the outer wall of the transistor body. The inner wall of the slot is provided with a limiting groove. A boss corresponding to the slot is provided at the top of the outer wall of the heat dissipation base. Elastic buckles are provided on the outer wall of the boss, and the elastic buckles are in interference fit with the limiting groove.

[0011] Preferably, a serpentine micro - channel is opened at the bottom end of the outer wall of the heat dissipation base. The cross - section of the serpentine micro - channel is semi - circular, with a diameter of 0.2 - 0.4 mm and a channel spacing of 0.5 - 0.8 mm. The serpentine micro - channel is filled with a phase - change material. The phase - change material is a mixture of paraffin and nano - copper powder, and the mass ratios of the mixture are 85% - 90% paraffin and 10% - 15% nano - copper powder respectively.

[0012] Preferably, a retractable heat dissipation fin is fixedly installed on the inner wall of the gradient heat dissipation groove. The retractable heat dissipation fin is connected to the inner wall of the gradient heat dissipation groove through a shape - memory alloy spring. The triggering temperature of the shape - memory alloy spring is 60 - 80 °C.

[0013] Preferably, a nest - shaped micropore array is opened on the outer wall of the retractable heat dissipation fin. The micropores of the nest - shaped micropore array have a diameter of 50 - 100 μm and a pore spacing of 150 - 200 μm. The interior of the micro-pores is filled with thermal conductive silicone grease, and boron nitride particles are doped in the thermal conductive silicone grease, and the doping ratio of the boron nitride particles is 5%-8%.

[0014] Preferably, the waveform contact surface is arranged between the copper layer and the graphene layer of the composite heat dissipation laminate, the outer surface of the composite heat dissipation laminate is covered with an insulating protective layer, the wave crest height of the waveform contact surface is set to 10-15μm, the wave trough depth is set to 5-8μm, and the wavelength interval is set to 50-80μm; The thermal interface material is a silver sintered layer, and carbon nanotubes are vertically and uniformly distributed inside the silver sintered layer. The two ends of the carbon nanotubes are respectively embedded in the bottom end of the transistor body and the top end of the heat dissipation base. The thickness of the silver sintered layer is 20-30μm, the diameter of the carbon nanotubes is 5-10nm, the length is 50-80μm, and the density is 106-107 roots / mm²; The insulating protective layer is made of a composite of polyimide and boron nitride. The mass ratio of boron nitride is 15%-20%. The thickness of the insulating protective layer is 10-15μm. The surface of the insulating protective layer is provided with concave and convex textures. The texture depth is 2-5μm, and the texture spacing is 20-30μm.

[0015] Preferably, annular heat dissipation fins are arranged on the outer wall side of the transistor body. The height of the annular heat dissipation fins is 1.0-1.5mm, the thickness is 0.3-0.5mm, and the spacing between adjacent annular heat dissipation fins is 0.8-1.2mm; A chamfer structure is arranged at the connection between the root of the annular heat dissipation fin and the transistor body. The chamfer angle is 30-45°, and the chamfer radius is 0.1-0.3mm; The outer wall top of the annular heat dissipation fin is provided with a transverse branch. The length of the transverse branch is 0.5-0.8mm. The end of the transverse branch is a conical structure. The cone angle is 15-20°. The outer surface of the transverse branch is coated with an aluminum nitride coating. The thickness of the aluminum nitride coating is 5-10μm.

[0016] Preferably, the usage method includes the following steps: S1. Attach the heat dissipation base to the heat dissipation area of the external circuit board through the thermal interface material. Align the boss with the slot at the bottom of the transistor body, and complete the rigid connection through the interference fit between the elastic buckle and the limit groove. The thermal interface material contacts the bottom surface of the transistor body; S2. Guide the heat at the top of the transistor body to spread to the edge through the diversion fins of the gradient heat dissipation groove, and the copper layer and the graphene layer of the composite heat dissipation laminate conduct heat alternately; S3. When the temperature of the transistor body exceeds 60°C, the shape memory alloy spring is heated and extended, pushing the telescopic heat sink to expand outward until it forms an angle of 30-45° with the inner wall of the gradient heat dissipation groove; S4. The phase change material in the serpentine microchannel absorbs heat and undergoes solid-liquid phase change, and the liquid phase change material flows along the microchannel to the low-temperature region of the heat dissipation base to release heat. S5. The distributed temperature heat conductor monitors the temperature distribution in the PN junction region and feeds back the data to the external control unit through micro-wires to dynamically adjust the heat dissipation intensity of the heat dissipation module.

[0017] Preferably, the usage method further includes the following steps: S11. The high thermal conductivity adhesive fills the interface gap between the copper layer and the graphene layer at the trough of the waveform contact surface. The vertically arranged carbon nanotubes establish a directional heat conduction channel from the transistor body to the heat dissipation base. The hemispherical protrusions break the boundary layer. The 45° inclined support plate transfers the heat to the heat dissipation base through the heat conduction column. The transverse branches of the annular heat dissipation fins accelerate the air flow peeling through the conical ends. S31. When the temperature reaches 60 - 80 °C, the shape memory alloy spring is triggered to stretch. After the retractable heat sink is unfolded, the thermal grease in the honeycomb micropore array on the surface of the retractable heat sink expands when heated, and the boron nitride particles overflow through the micropores and contact the air, accelerating local heat convection. S41. When the phase change material flows in the serpentine microchannel, the nano copper powder is adsorbed on the microporous ceramic layer on the inner wall of the microchannel by capillary action to form an additional heat conduction path. S42. After power-off, the phase change material solidifies and releases heat in the serpentine microchannel. The retractable heat sink shrinks and resets as the temperature decreases, and the elastic buckle allows for adaptive displacement of the thermal expansion difference between the heat dissipation base and the transistor body.

[0018] Compared with the prior art, the beneficial effects of the present invention are: 1. The present invention realizes the directional diffusion of heat from the center to the edge through the composite heat dissipation laminate, solves the problem of uneven heat dissipation caused by the anisotropy of homogeneous materials, improves the temperature distribution uniformity of the transistor body, and effectively avoids local overheating failure. 2. The present invention realizes the enhanced convective heat transfer by overflowing the thermal grease through the micropores by doping boron nitride thermal grease in the honeycomb micropore array, solves the problem that the static heat dissipation structure cannot adapt to transient heat loads, enables the automatic increase of the heat dissipation area under high-temperature conditions, and improves the dynamic heat dissipation efficiency. 3. The present invention fills the serpentine microchannel with a composite phase change material to form an additional heat conduction path through capillary effect, solves the problem of low thermal conductivity of conventional phase change materials, improves the heat storage density, and shortens the response time. 4. The present invention realizes the construction of a directional heat channel through the waveform contact surface in cooperation with the vertical carbon nanotube array, solves the problem of the thermal resistance bottleneck existing in the planar contact interface, and improves the heat conduction efficiency. Description of the Drawings

[0019] Figure 1Schematic front view structure diagram of the present invention; Figure 2 Schematic structure diagram of the composite heat dissipation laminate of the present invention; Figure 3 Schematic structure diagram of the heat dissipation partition of the present invention; Figure 4 Schematic structure diagram of the heat dissipation base of the present invention; Figure 5 Schematic structure diagram of the retractable heat sink of the present invention; Figure 6 Schematic structure diagram of the annular heat dissipation fin of the present invention.

[0020] In the figure: 1, transistor body; 2, heat dissipation base; 3, gradient heat dissipation groove; 4, composite heat dissipation laminate; 5, thermal interface material; 6, copper layer; 7, graphene layer; 8, serpentine microchannel; 9, retractable heat sink; 10, shape memory alloy spring; 11, nest-shaped micropore array; 12, corrugated contact surface; 13, annular heat dissipation fin; 14, lateral branch; 15, carbon nanotube; 16, heat dissipation partition; 17, heat conduction column; 18, support plate; 19, diversion fin; 20, distributed temperature heat conductor; 21, connection mechanism; 22, slot; 23, boss. Specific embodiments

[0021] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0022] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "upper", "lower", "inner", "outer", "front end", "rear end", "both ends", "one end", "the other end", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0023] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, terms such as "installation", "provided with", "connection", etc. should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0024] Please refer to Figure 1 , Figure 2 and Figure 3 , an embodiment provided by the present invention: a transistor with uniform heat dissipation, including a transistor body 1, a heat dissipation base 2, and a composite heat dissipation laminate 4. The bottom end of the outer wall of the transistor body 1 is attached to the heat dissipation base 2 through a thermal interface material 5; the composite heat dissipation laminate 4 includes a copper layer 6 and a graphene layer 7, and the copper layer 6 and the graphene layer 7 are alternately stacked and embedded in the inner wall of the gradient heat dissipation groove 3. The thickness of the copper layer 6 is set to 50 - 80 μm, and the thickness of the graphene layer 7 is set to 10 - 20 μm; The usage method includes the following steps: S1. Attach the heat dissipation base 2 to the heat dissipation area of the external circuit board through the thermal interface material 5, align the boss 23 with the slot 22 at the bottom of the transistor body 1, and complete the rigid connection through the interference fit between the elastic buckle and the limit groove. The thermal interface material 5 contacts the bottom surface of the transistor body 1; S2. Guide the heat at the top of the transistor body 1 to spread to the edge through the diversion fins 19 of the gradient heat dissipation groove 3, and the copper layer 6 and the graphene layer 7 of the composite heat dissipation laminate 4 conduct heat alternately; S3. When the temperature of the transistor body 1 exceeds 60 °C, the shape memory alloy spring 10 is heated and extended, pushing the telescopic heat sink 9 to expand outward until it forms an angle of 30 - 45° with the inner wall of the gradient heat dissipation groove 3; S4. The phase change material in the serpentine microchannel 8 absorbs heat and undergoes solid-liquid phase change, and the liquid phase change material flows along the microchannel 8 to the low-temperature area of the heat dissipation base 2 to release heat; S5. The distributed temperature heat conductor 20 monitors the temperature distribution in the PN junction area and feeds back the data to the external control unit through micro wires to dynamically adjust the heat dissipation intensity of the heat dissipation module; Further, first attach the heat dissipation base 2 to the heat dissipation area of the external circuit board through the thermal interface material 5, apply the thermal interface material 5 on the bonding surface of the heat dissipation base 2. At the same time, align the boss 23 on the heat dissipation base 2 with the slot 22 at the bottom of the transistor body 1 to make the elastic buckle and the limit groove form an interference fit; Then, heat is generated in the PN junction region of the transistor body 1 due to the passage of current. The diversion fins 19 inside the gradient heat dissipation groove 3 guide the heat at the top of the transistor body 1 to diffuse towards the edge. The copper layer 6 and the graphene layer 7 in the composite heat dissipation laminate 4 conduct heat alternately. Utilizing the high thermal conductivity of copper and the good two-dimensional heat conduction characteristics of graphene, the heat is evenly conducted. As the temperature gradually rises, the shape memory alloy spring 10 starts to stretch when heated, pushing the telescopic heat sink 9 to expand outwards until the telescopic heat sink 9 forms an angle of 30 - 45° with the inner wall of the gradient heat dissipation groove 3. The phase change material in the serpentine microchannel 8 opened at the bottom end of the outer wall of the heat dissipation base 2 absorbs heat and undergoes solid-liquid phase change, and the liquid phase change material flows along the microchannel 8 to the low-temperature region of the heat dissipation base 2 to release heat; Finally, the heat dissipation performance of the transistor is evaluated based on the temperature data recorded by the external control unit.

[0025] Please refer to Figure 1 , Figure 3 , Figure 5 and Figure 6 , and an embodiment provided by the present invention: A transistor with uniform heat dissipation, and the usage method further includes the following steps: S11. The interface gap between the copper layer 6 and the graphene layer 7 is filled with high thermal conductivity glue at the trough of the waveform contact surface 12. The vertically arranged carbon nanotubes 15 establish a directional heat conduction channel from the transistor body 1 to the heat dissipation base 2. The hemispherical protrusions break the boundary layer, and the 45° inclined support plate 18 transfers the heat to the heat dissipation base 2 through the heat conduction column 17. The transverse branches 14 of the annular heat dissipation fins 13 accelerate the airflow peeling through the conical ends; S31. When the temperature reaches 60 - 80 °C, the shape memory alloy spring 10 is triggered to stretch. After the telescopic heat sink 9 is unfolded, the thermal grease in the honeycomb micropore array 11 on the surface of the telescopic heat sink 9 expands when heated, and the boron nitride particles overflow through the micropores and contact the air, accelerating local heat convection; S41. When the phase change material flows in the serpentine microchannel 8, the nano copper powder is adsorbed on the microporous ceramic layer on the inner wall of the microchannel 8 through capillary action to form an additional heat conduction path; S42. After power-off, the phase change material solidifies and releases heat in the serpentine microchannel 8, and the telescopic heat sink 9 shrinks and resets as the temperature decreases, and the elastic buckle allows the heat dissipation base 2 to adaptively displace with the thermal expansion difference between the transistor body 1; The outer wall of the heat dissipation base 2 is provided with a serpentine microchannel 8 at the bottom end. The cross-section of the serpentine microchannel 8 is semi-circular, with a diameter of 0.2 - 0.4 mm and a channel spacing of 0.5 - 0.8 mm; The serpentine microchannel 8 is filled with a phase change material, and the phase change material is a mixture of paraffin and nano copper powder, and the mass ratios of the mixture are 85% - 90% paraffin and 10% - 15% nano copper powder respectively; An annular heat dissipation fin 13 is provided on the outer wall side of the transistor body 1. The height of the annular heat dissipation fin 13 is 1.0 - 1.5 mm, the thickness is 0.3 - 0.5 mm, and the distance between adjacent annular heat dissipation fins 13 is 0.8 - 1.2 mm; a chamfer structure is provided at the connection between the root of the annular heat dissipation fin 13 and the transistor body 1, the chamfer angle is 30 - 45°, and the chamfer radius is 0.1 - 0.3 mm; a transverse branch 14 is provided at the top end of the outer wall of the annular heat dissipation fin 13, the length of the transverse branch 14 is 0.5 - 0.8 mm, the end of the transverse branch 14 is a conical structure, the cone angle is 15 - 20°, and the outer surface of the transverse branch 14 is coated with an aluminum nitride coating, and the thickness of the aluminum nitride coating is 5 - 10 μm; Further, first, align the boss 23 on the bottom surface of the heat dissipation base 2 with the slot 22 at the bottom of the transistor body 1, and complete the mechanical fixation through the interference fit of the elastic buckle and the limit groove. Apply a silver sintering layer between the bottom end of the transistor body 1 and the top end of the heat dissipation base 2 to form a vertical heat conduction channel. Stack the copper layer 6 and the graphene layer 7 in an interleaved manner through the waveform contact surface 12, fill the valley with a high thermal conductivity adhesive, and embed it into the inner wall of the gradient heat dissipation groove 3; Then, the distributed temperature heat conductor 20 monitors the PN junction temperature. The heat is transferred to the support plate 18 through the heat conduction column 17. The diversion fin 19 destroys the air boundary layer through the hemispherical protrusion, diffuses the heat from the center to the edge, and the heat diffusion efficiency is increased by 30%. The carbon nanotube 15 conducts the heat from the bottom of the transistor body 1 to the heat dissipation base 2; Finally, when the temperature rises to 80 °C, the telescopic heat dissipation fin 9 is fully deployed, and the heat dissipation area is increased by 1.5 times. The thermal conductive silicone grease in the honeycomb micropore array 11 is completely liquefied, and the boron nitride particles form a continuous heat conduction film, and the local heat flux density is reduced by 40%. After power-off, the phase change material in the serpentine microchannel 8 solidifies and releases latent heat. At the same time, the shape memory alloy spring 10 contracts, and the telescopic heat dissipation fin 9 resets. The elastic buckle compensates for the thermal expansion difference between the transistor body 1 and the heat dissipation base 2 to avoid interface cracking.

[0026] Please refer to Figure 1 、 Figure 2 and Figure 3, an embodiment provided by the present invention: a transistor with uniform heat dissipation. The gradient heat dissipation groove 3 extends from the center of the top end of the outer wall of the transistor body 1 to both side edges along the heat dissipation partition 16. The heat dissipation partition 16 includes a heat conduction column 17, a support plate 18, and a diversion fin 19. The top end of the outer wall of the heat conduction column 17 is welded to the bottom surface of the support plate 18, the bottom end of the heat conduction column 17 is vertically embedded in the top end of the transistor body 1, the diversion fin 19 is fixedly installed on the top surface of the support plate 18 at an inclination angle of 45°. The main fin of the diversion fin 19 is set in an inverted V shape, with reinforcing ribs provided at the end of the main fin. The top end of the main fin extends with sub-fins on both sides, and hemispherical protrusions are provided at the ends of the sub-fins; the groove depth of the gradient heat dissipation groove 3 gradually decreases from 0.3 - 0.5 mm in the central region to 0.1 - 0.2 mm at the edge, and the groove width expands from 1.0 - 1.5 mm in the center to 2.0 - 2.5 mm at the edge; The thermal interface material 5 is a silver sintered layer. Carbon nanotubes 15 are uniformly distributed and vertically arranged inside the silver sintered layer. Both ends of the carbon nanotubes 15 are respectively embedded in the bottom end of the transistor body 1 and the top end of the heat dissipation base 2. The thickness of the silver sintered layer is 20 - 30 μm, the diameter of the carbon nanotubes 15 is 5 - 10 nm, the length is 50 - 80 μm, and the density is 106 - 107 pieces / mm²; the insulating protective layer is made of a composite of polyimide and boron nitride, the mass ratio of boron nitride is 15% - 20%, the thickness of the insulating protective layer is 10 - 15 μm, the surface of the insulating protective layer is provided with concave and convex textures, the texture depth is 2 - 5 μm, and the texture spacing is 20 - 30 μm; Further, first, the composite heat dissipation laminate 4 is embedded in the inner wall of the gradient heat dissipation groove 3, and the bottom end of the outer wall of the transistor body 1 is attached to the heat dissipation base 2 using the thermal interface material 5 to accurately embed the carbon nanotubes 15; Then, a telescopic heat dissipation fin 9 is installed on the inner wall of the gradient heat dissipation groove 3. The telescopic heat dissipation fin 9 is connected to the inner wall of the gradient heat dissipation groove 3 through a shape memory alloy spring 10. The triggering temperature of the shape memory alloy spring 10 is set at 70°C. A nest-shaped micropore array 11 is opened on the outer wall of the telescopic heat dissipation fin 9. The diameter of the micropores is 70 μm, and the micropores are filled with thermal conductive silicone grease doped with boron nitride particles. The doping ratio of the boron nitride particles is 6%. A distributed temperature heat conductor 20 is buried inside the transistor body 1. The distributed temperature heat conductor 20 is distributed in a grid shape along the PN junction region of the transistor body 1 and is connected to an external control unit through micro-wires. The coupling mechanism 21 on the side surface of the outer wall of the heat dissipation base 2 is connected to the transistor body 1, aligning the slot 22 with the boss 23, and completing the rigid connection through the interference fit of the elastic buckle and the limit groove; Finally, observe the data fed back by the distributed temperature heat conductor 20. When the temperature of the transistor body 1 exceeds 60 °C, the shape memory alloy spring 10 is heated and stretched, pushing the retractable heat sink 9 to expand outward until it forms an angle of 35° with the inner wall of the gradient heat dissipation groove 3. The thermal grease in the honeycomb micropore array 11 on the surface of the retractable heat sink 9 expands when heated, and the boron nitride particles overflow through the micropores and come into contact with the air, accelerating local heat convection.

[0027] Please refer to Figure 1 、 Figure 3 and Figure 5 For an embodiment provided by the present invention: a transistor with uniform heat dissipation, a retractable heat sink 9 is fixedly installed on the inner wall of the gradient heat dissipation groove 3. The retractable heat sink 9 is connected to the inner wall of the gradient heat dissipation groove 3 through a shape memory alloy spring 10, and the triggering temperature of the shape memory alloy spring 10 is 60 - 80 °C; The outer wall of the retractable heat sink 9 is provided with a honeycomb micropore array 11. The micropores of the honeycomb micropore array 11 have a diameter of 50 - 100 μm and a pore spacing of 150 - 200 μm; the micropores are filled with thermal grease, and boron nitride particles are doped in the thermal grease, and the doping ratio of the boron nitride particles is 5% - 8%; Furthermore, first select copper as the base material, use CNC precision machining to prepare the gradient heat dissipation groove 3, the groove depth is designed to be 3 mm - 5 mm, a spring fixing slot is opened on the inner wall, and a chip installation platform is reserved at the center of the bottom of the groove. Cut a phosphor bronze sheet with a thickness of 0.3 mm as the retractable heat sink 9. One end of the shape memory alloy spring 10 is fixed in the heat dissipation groove slot by laser welding, and the other end is riveted to the heat sink boss to ensure that the telescopic direction is consistent with the depth direction of the heat dissipation groove; Then use femtosecond laser processing technology to process the honeycomb micropore array 11 on the outer wall of the heat sink 9, then prepare the thermal grease doped with boron nitride particles, and use the pressure injection method to fill the slurry into the micropores; finally, apply a 0.05 mm thick graphene thermal conductive adhesive on the chip installation platform, paste and fix the transistor chip, and cover the top of the heat dissipation groove with an aluminum alloy heat dissipation fin, and lock it with an M3 screw to the heat dissipation groove.

[0028] Please refer to Figure 1 、 Figure 3 and Figure 4, an embodiment provided by the present invention: a transistor with uniform heat dissipation, where the copper layer 6 and the graphene layer 7 are bonded to each other through a highly thermally conductive adhesive at each overlapping layer, and the highly thermally conductive adhesive is filled in the troughs of the waveform contact surface 12; a distributed temperature heat conductor 20 is embedded inside the transistor body 1, and the distributed temperature heat conductor 20 is distributed in a grid pattern along the PN junction region of the transistor body 1. The distributed temperature heat conductor 20 is connected to an external control unit through micro-wires. A coupling mechanism 21 is rigidly connected to the outer side surface of the heat dissipation base 2. The coupling mechanism 21 includes a slot 22 and a boss 23. The slots 22 are arranged in an array on the bottom surface of the outer wall of the transistor body 1. A limiting groove is provided on the inner wall of the slot 22. A boss 23 corresponding to the slot 22 is provided at the top end of the outer wall of the heat dissipation base 2. An elastic buckle is provided on the outer wall of the boss 23, and the elastic buckle is in interference fit with the limiting groove; The waveform contact surface 12 is arranged between the copper layer 6 and the graphene layer 7 of the composite heat dissipation laminate 4. The outer surface of the composite heat dissipation laminate 4 is covered with an insulating protective layer. The peak height of the waveform contact surface 12 is set to 10 - 15 μm, the trough depth is set to 5 - 8 μm, and the wavelength interval is set to 50 - 80 μm; Further, first, the transistor body 1 is fabricated using a silicon-based semiconductor process. A buried groove for the distributed temperature heat conductor 20 is reserved in the PN junction region. Arrayed slots 22 are etched on the bottom surface of the transistor body 1. The waveform contact surface 12 is fabricated on the surface of the copper foil using a vacuum sputtering method. The graphene layer 7 and the copper layer 6 are thermally pressed and bonded together, and a highly thermally conductive adhesive is filled at the waveform contact surface 12. A boss 23 corresponding to the slot 22 is machined at the top end of the heat dissipation base 2; Then, the micro-wires of the distributed temperature heat conductor 20 are connected to the interface of the external control unit through ultrasonic welding. Thermal grease is applied to the top surface of the transistor body 1. The copper layer 6 of the composite heat dissipation laminate 4 is attached to the top surface. Then, the boss 23 of the heat dissipation base 2 is aligned with the slot 22 of the transistor body 1 and vertically pressed in until the buckle is completely engaged with the limiting groove. The deformation uniformity of the buckle is detected through an optical microscope. Finally, a working current of 10 A is applied, and the temperature of the PN junction region is detected through an infrared thermal imager.

[0029] Working principle: First, when heat is generated in the PN junction region of the transistor body 1 due to the passage of current, the distributed temperature heat conductor 20 monitors the temperature distribution in real time and feeds the data back to the external control unit. The heat is vertically transferred to the support plate 18 through the heat conduction columns 17 of the gradient heat dissipation groove 3. The guide fins 19 diffuse the heat towards the edge at an inclination angle of 45°. The hemispherical protrusions at the top ends of the inverted V-shaped main fins and the sub-fins break the air boundary layer; Then, the bottom of the transistor body 1 is connected to the heat dissipation base 2 through the thermal interface material 5. The vertically arranged carbon nanotubes 15 within the layer establish a directional heat conduction channel, rapidly transferring heat to the heat dissipation base 2. The copper layer 6 and the graphene layer 7 on the inner wall of the gradient heat dissipation groove 3 are stacked alternately, increasing the contact area through the wavy contact surface 12. The high thermal conductivity adhesive fills the valley gaps, achieving lateral uniform heat conduction by utilizing the high thermal conductivity of copper and the two-dimensional heat conduction characteristics of graphene. When the temperature of the heat dissipation base 2 rises, the paraffin-nano copper powder mixture in the serpentine microchannel 8 undergoes solid-liquid phase change, and the liquid material flows along the microchannel towards the low-temperature region. The nano copper powder forms an additional heat conduction path in the microporous ceramic layer. When the temperature exceeds 60 °C, the shape memory alloy spring 10 extends, pushing the retractable heat sink 9 to unfold to an angle of 30 - 45 °. The thermal grease in the surface pit-like microporous array 11 expands when heated, and the boron nitride particles overflow to accelerate local heat convection. When the temperature reaches 80 °C, the heat sink is fully unfolded, further increasing the heat dissipation area. Finally, the annular heat dissipation fins 13 optimize the airflow separation through the root chamfer and the lateral branches 14, and the aluminum nitride coating enhances the surface heat conduction. At the same time, the elastic buckle of the connection mechanism 21 allows the heat dissipation base 2 and the transistor body 1 to generate adaptive displacement due to the thermal expansion difference, avoiding structural stress. After power-off, the phase change material solidifies and releases the remaining heat, and the retractable heat sink 9 resets with the temperature drop, completing the heat dissipation cycle.

[0030] 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 characteristics of the present invention. Therefore, from any perspective, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be encompassed within the present invention. Any reference signs in the claims should not be regarded as limiting the claims involved.

Claims

1. A transistor with uniform heat dissipation, characterized in that: It comprises a transistor body (1), a heat dissipation base (2) and a composite heat dissipation laminate (4), wherein the bottom end of the outer wall of the transistor body (1) is attached to the heat dissipation base (2) via a thermal interface material (5); The composite heat dissipation laminate (4) comprises a copper layer (6) and a graphene layer (7), wherein the copper layer (6) and the graphene layer (7) are staggered and embedded in the inner wall of the gradient heat dissipation groove (3), the thickness of the copper layer (6) is set to 50-80 μm, and the thickness of the graphene layer (7) is set to 10-20 μm.

2. The transistor with uniform heat dissipation according to claim 1, characterized in that: The gradient heat dissipation groove (3) extends from the heat dissipation baffle (16) along the center of the top of the outer wall of the transistor body (1) to the edges on both sides, the heat dissipation baffle (16) comprises a heat conducting column (17), a support plate (18) and a guide fin (19), the top of the outer wall of the heat conducting column (17) is welded to the bottom surface of the support plate (18), the bottom end of the heat conducting column (17) is vertically embedded in the top of the transistor body (1), the guide fin (19) is fixedly mounted on the top surface of the support plate (18) at an inclination angle of 45°, the main fin of the guide fin (19) is arranged in an inverted V shape, the end of the main fin is provided with a reinforcing rib, sub-fins extend on both sides of the top of the main fin, and the end of the sub-fin is provided with a hemispherical protrusion; The groove depth of the gradient heat dissipation groove (3) gradually decreases from 0.3-0.5 mm in the central area to 0.1-0.2 mm at the edge, and the groove width expands from 1.0-1.5 mm in the center to 2.0-2.5 mm at the edge.

3. The transistor with uniform heat dissipation according to claim 1, characterized in that: Each overlapping layer of the copper layer (6) and the graphene layer (7) is bonded by a high thermal conductivity adhesive, and the high thermal conductivity adhesive is filled in the valleys of the corrugated contact surface (12); A distributed temperature heat conductor (20) is embedded inside the transistor body (1), and the distributed temperature heat conductor (20) is distributed in a grid shape along the PN junction region of the transistor body (1). The distributed temperature heat conductor (20) is connected to an external control unit via a micro-wire. The side surface of the outer wall of the heat dissipation base (2) is rigidly connected to a coupling mechanism (21), and the coupling mechanism (21) comprises a slot (22) and a boss (23). The slot (22) is arrayed on the bottom surface of the outer wall of the transistor body (1), and the inner wall of the slot (22) is provided with a limiting groove. The top of the outer wall of the heat dissipation base (2) is provided with a boss (23) corresponding to the slot (22), and the outer wall of the boss (23) is provided with an elastic buckle, and the elastic buckle is interference-fitted with the limiting groove.

4. The transistor with uniform heat dissipation according to claim 1, characterized in that: A serpentine microchannel (8) is provided at the bottom end of the outer wall of the heat dissipation base (2), the cross section of the serpentine microchannel (8) is semicircular, the diameter is 0.2-0.4 mm, and the channel spacing is 0.5-0.8 mm; The serpentine microchannel (8) is filled with a phase change material, which is a mixture of paraffin wax and nano copper powder, with the mass proportion of the mixture being 85%-90% paraffin wax and 10%-15% nano copper powder.

5. The transistor with uniform heat dissipation according to claim 1, characterized in that: A retractable heat sink (9) is fixedly mounted on the inner wall of the gradient heat sink (3); the retractable heat sink (9) is connected to the inner wall of the gradient heat sink (3) via a shape memory alloy spring (10); the trigger temperature of the shape memory alloy spring (10) is 60-80°C.

6. The transistor with uniform heat dissipation according to claim 5, characterized in that: The outer wall of the retractable heat sink (9) is provided with a nest-shaped micropore array (11), the micropore diameter of the nest-shaped micropore array (11) is 50-100 μm, and the pore spacing is 150-200 μm; The micropores are filled with thermal grease, which is doped with boron nitride particles, and the doping ratio of the boron nitride particles is 5%-8%.

7. The transistor with uniform heat dissipation according to claim 3, characterized in that: The corrugated contact surface (12) is arranged between the copper layer (6) and the graphene layer (7) of the composite heat dissipation laminate (4); the outer surface of the composite heat dissipation laminate (4) is covered with an insulating protective layer; the crest height of the corrugated contact surface (12) is set to 10-15 μm, the trough depth is set to 5-8 μm, and the wavelength interval is set to 50-80 μm; The thermal interface material (5) is a silver sintered layer, and carbon nanotubes (15) are evenly distributed and arranged vertically inside the silver sintered layer. The two ends of the carbon nanotubes (15) are respectively embedded in the bottom end of the transistor body (1) and the top end of the heat dissipation base (2). The thickness of the silver sintered layer is 20-30 μm, the diameter of the carbon nanotubes (15) is 5-10 nm, the length is 50-80 μm, and the density is 106-107 tubes / mm²; The insulating protective layer is made of a composite of polyimide and boron nitride, with boron nitride accounting for 15%-20% by mass. The thickness of the insulating protective layer is 10-15μm, and the surface of the insulating protective layer is provided with a concave-convex texture with a texture depth of 2-5μm and a texture spacing of 20-30μm.

8. The transistor with uniform heat dissipation according to claim 1, characterized in that: An annular heat dissipation fin (13) is provided on the side surface of the outer wall of the transistor body (1); the annular heat dissipation fin (13) has a height of 1.0-1.5 mm and a thickness of 0.3-0.5 mm; and the spacing between adjacent annular heat dissipation fins (13) is 0.8-1.2 mm; A chamfer structure is provided at the connection between the root of the annular heat dissipation fin (13) and the transistor body (1), the chamfer angle is 30-45°, and the chamfer radius is 0.1-0.3 mm; A transverse branch (14) is provided at the top end of the outer wall of the annular heat dissipation fin (13); the length of the transverse branch (14) is 0.5-0.8 mm; the end of the transverse branch (14) is a conical structure; the cone angle is 15-20 degrees; the outer surface of the transverse branch (14) is plated with an aluminum nitride coating; the thickness of the aluminum nitride coating is 5-10 μm.

9. A method for using a transistor with uniform heat dissipation, applicable to the transistor with uniform heat dissipation according to any one of claims 1 to 8, characterized in that: The method of use comprises the following steps: S1, attaching the heat dissipation base (2) to the heat dissipation area of ​​the external circuit board through the thermal interface material (5), aligning the boss (23) with the slot (22) at the bottom of the transistor body (1), completing the rigid connection through the interference fit of the elastic buckle and the limiting groove, and the thermal interface material (5) is in contact with the bottom surface of the transistor body (1); S2, guiding the heat on the top of the transistor body (1) to diffuse toward the edge through the guide fins (19) of the gradient heat dissipation groove (3), and alternately conducting heat through the copper layer (6) and the graphene layer (7) of the composite heat dissipation laminate (4); S3. When the temperature of the transistor body (1) exceeds 60°C, the shape memory alloy spring (10) is heated and stretched, pushing the retractable heat sink (9) to expand outwards until an angle of 30-45° is formed with the inner wall of the gradient heat sink (3); S4, the phase change material in the serpentine microchannel (8) absorbs heat and undergoes a solid-liquid phase change, and the liquid phase change material flows along the microchannel (8) to the low-temperature area of ​​the heat dissipation base (2) to release heat; S5. The distributed temperature heat conductor (20) monitors the temperature distribution of the PN junction area and feeds back the data to the external control unit through the micro-conductor to dynamically adjust the heat dissipation intensity of the heat dissipation module.

10. The method for using a transistor with uniform heat dissipation according to claim 9, characterized in that: The method of use also includes the following steps: S11, the high thermal conductivity glue at the trough of the corrugated contact surface (12) fills the interface gap between the copper layer (6) and the graphene layer (7), the vertically arranged carbon nanotubes (15) establish a directional heat conduction channel from the transistor body (1) to the heat dissipation base (2), the hemispherical protrusion destroys the boundary layer, the 45° inclined support plate (18) transfers heat to the heat dissipation base (2) through the thermal conductive column (17), and the lateral branch (14) of the annular heat dissipation fin (13) accelerates airflow stripping through the conical end; S31. When the temperature reaches 60-80°C, the shape memory alloy spring (10) is triggered to extend. After the retractable heat sink (9) is unfolded, the thermal conductive silicone grease in the dimple-shaped micropore array (11) on the surface of the retractable heat sink (9) expands due to the heat, and the boron nitride particles overflow through the micropores and come into contact with the air, thereby accelerating local heat convection. S41, when the phase change material flows in the serpentine microchannel (8), the nano copper powder is adsorbed on the microporous ceramic layer on the inner wall of the microchannel (8) by capillary action, forming an additional heat conduction path; S42. After power is turned off, the phase change material solidifies in the serpentine microchannel (8) to release heat, and the retractable heat sink (9) shrinks and resets as the temperature decreases. The elastic buckle allows the heat sink base (2) and the transistor body (1) to adaptively displace due to the thermal expansion difference.

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