Ceramic metal mixed pressure printed circuit board and detection equipment

Abstract

This application provides a ceramic-metal hybrid laminated printed circuit board and testing equipment, relating to the field of printed circuit board manufacturing technology. The ceramic-metal hybrid laminated printed circuit board includes: a metal heat sink having a metal base and a metal platform protruding to one side from the metal base; a resistance coil printed circuit board stacked on the laminated surface of the metal platform; a ceramic thermally conductive component stacked on the side of the resistance coil printed circuit board opposite to the metal platform; and a first thermally conductive adhesive layer and a second thermally conductive adhesive layer. The first thermally conductive adhesive layer laminates and connects the resistance coil printed circuit board to the metal platform, and the second thermally conductive adhesive layer laminates and connects the resistance coil printed circuit board to the ceramic thermally conductive component. This ceramic-metal hybrid laminated printed circuit board can form a structure with integrated heat generation, heat dissipation, and heat dissipation within a limited thickness, and with low interlayer thermal resistance, ensuring stable correspondence between the resistance heating area, the ceramic thermally conductive area, and the metal heat dissipation area, while also considering rapid temperature response and temperature uniformity.

Description

Technical Field

[0001] This application relates to the field of printed circuit board manufacturing technology, and more specifically, to a ceramic-metal hybrid printed circuit board and testing equipment. Background Technology

[0002] Polymerase chain reaction (PCR) amplification instruments achieve nucleic acid amplification by rapidly and repeatedly heating and cooling the reaction system. Its high-power temperature control module is usually composed of a printed circuit board heating module with a resistance coil and a metal heat sink module. The heat transfer efficiency and temperature uniformity directly affect the amplification cycle and detection efficiency.

[0003] Current temperature control substrates mainly use FR-4 organic boards, metal substrates, or ceramic copper-clad boards. FR-4 organic boards offer flexible wiring and lower cost, but their thermal conductivity is limited, making it difficult to dissipate the heat generated by the resistance coil in a timely manner. Metal substrates, while improving heat dissipation, suffer from problems such as insufficient matching of thermal expansion coefficients, easy delamination during thermal cycling, and limited insulation withstand voltage. Ceramic copper-clad boards combine high thermal conductivity and insulation, but ceramics are brittle and prone to breakage during lamination and assembly.

[0004] On the other hand, existing heating and cooling modules are mostly relatively independent structures with large interlayer thermal resistance, making it difficult to form a continuous and stable short heat transfer path. The common cooling rate is about 5~15℃ / s, which can only meet the needs of routine testing. As the requirements for temperature control response speed and cycle stability of rapid nucleic acid testing equipment increase, the temperature control module needs to achieve a cooling rate of about 30~50℃ / s, while taking into account the uniformity of resistance coil resistance, insulation withstand voltage, thermal cycle reliability, and temperature uniformity of the heating surface.

[0005] Therefore, how to integrate high thermal conductivity, heat generation, and insulation structures into one unit and reduce interlayer thermal resistance has become an urgent problem to be solved in existing PCR temperature control modules. Summary of the Invention

[0006] The purpose of this application is to address the shortcomings of the prior art by providing a ceramic-metal hybrid printed circuit board and testing equipment, which can form a structure with integrated heat generation, heat dissipation and heat dissipation within a limited thickness and low interlayer thermal resistance, so that the resistance heating area, ceramic heat conduction area and metal heat dissipation area remain stably corresponding, while taking into account rapid temperature response and temperature uniformity.

[0007] To achieve the above objectives, the technical solutions adopted in the embodiments of this application are as follows: One aspect of this application provides a ceramic-metal hybrid printed circuit board, comprising: a metal heat sink having a metal base and a metal platform protruding to one side from the metal base; a resistance coil printed circuit board stacked on the laminated surface of the metal platform; a ceramic thermally conductive component stacked on the side of the resistance coil printed circuit board away from the metal platform; and a first thermally conductive adhesive layer and a second thermally conductive adhesive layer respectively located on both sides of the resistance coil printed circuit board, wherein the first thermally conductive adhesive layer laminates the resistance coil printed circuit board to the metal platform, and the second thermally conductive adhesive layer laminates the resistance coil printed circuit board to the ceramic thermally conductive component; wherein the resistance coil printed circuit board has a resistance heating area, and the resistance heating area, the metal platform, and the ceramic thermally conductive component at least partially overlap along the thickness direction of the ceramic-metal hybrid printed circuit board.

[0008] Optionally, a lamination groove is provided on the surface of the metal platform away from the metal base. The printed circuit board of the resistance coil, the first thermally conductive adhesive layer and the second thermally conductive adhesive layer are all located in the lamination groove. The surface of the second thermally conductive adhesive layer away from the printed circuit board of the resistance coil is flush with the groove opening of the lamination groove.

[0009] Optionally, the resistance heating zone is provided with a main resistance coil and a secondary resistance coil.

[0010] Optionally, the main resistance coil and the secondary resistance coil are arranged in a serpentine pattern along the length of the resistance heating zone, and the secondary resistance coil is located within the gap formed by the arrangement of the main resistance coil.

[0011] Optionally, the linewidth of the main resistor coil is 2 to 3 times the linewidth of the secondary resistor coil.

[0012] Optionally, the linewidth of the main resistor coil is 6mil to 8mil, and the linewidth of the secondary resistor coil is 2mil to 3.94mil.

[0013] Optionally, the resistance of the main resistor coil is 3.5Ω~4.5Ω, and the resistance of the secondary resistor coil is 5Ω~8Ω.

[0014] Optionally, both the first thermally conductive adhesive layer and the second thermally conductive adhesive layer are formed by lamination and curing of a high thermally conductive prepreg without fiberglass cloth, and the thermal conductivity is not less than 3.0 W / (m·K).

[0015] Optionally, the metal base is a copper base, the metal platform is a copper platform, and the thermal conductivity of the metal base and the metal platform is ≥380W / (m·K).

[0016] Optionally, the total thickness of the metal base and the metal platform is 13mm~15mm, the thickness of the metal base is 9mm~10mm, and the thickness of the metal platform is 4mm~5mm.

[0017] Optionally, the ceramic heat-conducting element is an aluminum nitride ceramic sheet with a thermal conductivity of not less than 170 W / (m·K) and a thickness of 0.35 mm to 0.45 mm.

[0018] Optionally, the ceramic heat-conducting component has an electroplated copper layer and a nickel-gold layer sequentially disposed on the surface of the printed circuit board away from the resistor coil.

[0019] Optionally, the thickness of the insulating dielectric layer on the printed circuit board of the resistor coil is 0.07mm to 0.10mm.

[0020] In another aspect of the embodiments of this application, a testing device is provided, including a ceramic-metal hybrid printed circuit board as described in any of the above claims.

[0021] The beneficial effects of this application include: The ceramic-metal hybrid printed circuit board provided in this application relies on an integrated design of a metal heat sink, a ceramic thermally conductive component, and a thermally conductive adhesive layer. This reduces the contact thermal resistance caused by fastener assembly and thick adhesive layers, shortening the distance heat is transferred from the resistance heating area to the ceramic working surface and the metal heat sink. Furthermore, the combined diffusion effect of the metal platform and the ceramic thermally conductive component reduces local hot spots, ensuring a stable correspondence between the resistance heating area, the ceramic thermally conductive area, and the metal heat sink, while also considering rapid temperature response and temperature uniformity. The heat dissipation rate of this ceramic-metal hybrid printed circuit board can be increased to approximately 30℃ / s~50℃ / s, the time to drop from 95℃ to 50℃ can be less than 1.2s, and the temperature difference of the heating module can be controlled within 3℃, thus balancing rapid thermal cycling, temperature uniformity, and structural integration. Attached Figure Description

[0022] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the structure of a ceramic-metal hybrid printed circuit board provided in an embodiment of this application; Figure 2 A schematic diagram of the structure of the metal heat sink in the ceramic-metal hybrid printed circuit board provided in the embodiments of this application; Figure 3 This is a schematic diagram of the structure of the resistor coil printed circuit board in the ceramic-metal hybrid printed circuit board provided in the embodiments of this application; Figure 4 This is a partially enlarged schematic diagram of the resistor coil printed circuit board in the ceramic-metal hybrid printed circuit board provided in the embodiments of this application; Figure 5 One of the temperature simulation diagrams of the ceramic thermal conductive component in the ceramic-metal hybrid printed circuit board provided in the embodiments of this application; Figure 6 This is the second temperature simulation diagram of the ceramic heat-conducting component in the ceramic-metal hybrid printed circuit board provided in the embodiments of this application; Figure 7 The third temperature simulation diagram of the ceramic heat-conducting component in the ceramic-metal hybrid printed circuit board provided in the embodiments of this application; Figure 8 The fourth temperature simulation diagram of the ceramic heat-conducting component in the ceramic-metal hybrid printed circuit board provided in the embodiments of this application.

[0024] Icons: 10-Ceramic-metal hybrid printed circuit board; 11-Metal heat sink; 111-Metal base; 112-Metal platform; 113-Laminator groove; 114-Positioning post; 12-Resistance coil printed circuit board; 121-Resistance heating area; 122-Main resistance coil; 123-Secondary resistance coil; 13-Ceramic thermal conductive component; 14-First thermally conductive adhesive layer; 15-Second thermally conductive adhesive layer. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0026] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. It should be noted that, unless otherwise specified, the various features in the embodiments of this application can be combined with each other, and the combined embodiments are still within the protection scope of this application.

[0027] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0028] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this application is in use. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0029] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set up," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0030] Please refer to Figure 1 and Figure 2 One aspect of this application provides a ceramic-metal hybrid printed circuit board 10, comprising: a metal heat sink 11 having a metal base 111 and a metal platform 112 protruding to one side from the metal base 111; a resistance coil printed circuit board 12, laminated on the metal platform 112; a ceramic heat-conducting element 13, laminated on the side of the resistance coil printed circuit board 12 away from the metal platform 112; and a first thermally conductive adhesive layer 14 and a second thermally conductive adhesive layer 15 located on both sides of the resistance coil printed circuit board 12, wherein the first thermally conductive adhesive layer 14 laminates the resistance coil printed circuit board 12 to the metal platform 112, and the second thermally conductive adhesive layer 15 laminates the resistance coil printed circuit board 12 to the ceramic heat-conducting element 13; wherein the resistance coil printed circuit board 12 has a resistance heating area 121, and the resistance heating area 121, the metal platform 112, and the ceramic heat-conducting element 13 at least partially overlap along the thickness direction of the ceramic-metal hybrid printed circuit board 10.

[0031] It should be noted that "mixed lamination" refers to the process of stacking the metal heat sink 11, the resistance coil printed circuit board 12, the ceramic heat conductor 13, and the curable thermally conductive adhesive material in predetermined layers and bonding them together under temperature and pressure. The thickness direction (also known as the lamination direction) refers to the direction in which the layers are arranged sequentially from the metal heat sink 11 to the ceramic heat conductor 13. The resistance heating zone 121 refers to the area on the resistance coil printed circuit board 12 where heat is generated by the resistance effect after the conductive lines are energized.

[0032] The metal heat sink 11 includes a metal base 111 and a metal platform 112 protruding to one side from the metal base 111. The metal base 111 provides a mounting base and a main body for heat transfer to an external cooling mechanism, while the metal platform 112 forms a local laminated surface corresponding to the resistance coil printed circuit board 12. The resistance coil printed circuit board 12 is sandwiched between the metal platform 112 and the ceramic heat conductor 13. When energized, the resistance heating area 121 formed by the conductive lines directly generates heat. A first thermally conductive adhesive layer 14 reliably bonds the resistance coil printed circuit board 12 to the metal platform 112, and a second thermally conductive adhesive layer 15 reliably bonds the resistance coil printed circuit board 12 to the ceramic heat conductor 13, thus forming a continuous laminated thermal path between the originally separate heating, heat equalization, and heat dissipation components.

[0033] The term "at least partially overlapping along the thickness direction" means that the resistance heating area 121, the metal platform 112, and the ceramic heat-conducting component 13 overlap within the projection range perpendicular to the plate surface. It does not require that the three have the same shape or area. This ensures that the main heating area corresponds to the upper and lower heat-conducting areas, while also reserving design space for terminals, wiring, mounting holes, or non-heating functional areas.

[0034] The aforementioned ceramic-metal hybrid printed circuit board 10, relying on the integrated design of metal heat sink 11, ceramic heat conductor 13, and thermally conductive adhesive layer, reduces the contact thermal resistance caused by fastener assembly and thick adhesive layers. This shortens the distance heat is transferred from the resistance heating area 121 to the ceramic working surface and the metal heat sink. Furthermore, the combined diffusion effect of the metal platform 112 and the ceramic heat conductor 13 reduces local hot spots, ensuring a stable correspondence between the resistance heating area 121, the ceramic heat conductor area, and the metal heat sink area, while also considering rapid temperature response and temperature uniformity. The heat dissipation rate of this ceramic-metal hybrid printed circuit board 10 can be increased to approximately 30℃ / s~50℃ / s, the time to drop from 95℃ to 50℃ can not exceed 1.2s, and the temperature difference of the heating module can be controlled within 3℃, thus balancing rapid thermal cycling, temperature uniformity, and structural integration.

[0035] Optionally, the surface of the metal platform 112 facing away from the metal base 111 is provided with a lamination groove 113. The resistor coil printed circuit board 12, the first thermally conductive adhesive medium layer 14 and the second thermally conductive adhesive medium layer 15 are all located in the lamination groove 113. The surface of the second thermally conductive adhesive medium layer 15 facing away from the resistor coil printed circuit board 12 is flush with the groove opening of the lamination groove 113.

[0036] A lamination groove 113 is formed on the surface of the metal platform 112, and the resistor coil printed circuit board 12, the first thermally conductive adhesive layer 14, and the second thermally conductive adhesive layer 15 are all located within the lamination groove 113. This reduces the thickness of the ceramic-metal hybrid printed circuit board 10 and uses the sidewall of the lamination groove 113 to limit the position of the resistor coil printed circuit board 12. The surface of the second thermally conductive adhesive layer 15, which faces away from the resistor coil printed circuit board 12, is flush with the groove opening of the lamination groove 113, which eliminates the assembly gap between the ceramic thermally conductive component 13 and the metal platform 112, avoiding incomplete adhesion and lifting of the ceramic thermally conductive component 13. The bonding uniformity and structural flatness are significantly improved.

[0037] Optionally, the metal base 111 is a copper base, the metal platform 112 is a copper platform, and the thermal conductivity of the metal base 111 and the metal platform 112 is ≥380W / (m·K).

[0038] Copper with a thermal conductivity ≥380W / (m·K) has high thermal conductivity and good heat diffusion performance, enabling it to quickly absorb heat from the printed circuit board 12 of the resistance coil and diffuse it along the plane and thickness directions. At the same time, copper has sufficient mechanical strength and processing performance, making it easy to form structures such as bases, protruding platforms, mounting holes, and positioning posts 114.

[0039] Optionally, the total thickness of the metal base 111 and the metal platform 112 is 13mm to 15mm, the thickness of the metal base 111 is 9mm to 10mm, and the thickness of the metal platform 112 is 4mm to 5mm.

[0040] It is understandable that the total thickness refers to the overall dimension of the metal base 111 and the metal platform 112 in the stacking direction. The thickness of the metal heat sink 11 is related to the heat dissipation efficiency; if the thickness is too small, the heat dissipation performance will decrease, while if the thickness is too large, it will prevent installation in the equipment given a fixed allowable size. The aforementioned thickness range allows the metal heat sink 11 to balance heat dissipation efficiency and volume, and can be successfully installed in the equipment while maintaining good thermal conductivity and heat dissipation performance.

[0041] By combining materials and thicknesses, a balance can be achieved between rapid heat conduction, thermal diffusion, mechanical stability, and overall installation space, reducing warpage of the metal heat sink 11 during hot pressing and repeated thermal cycling, thereby improving the consistency of the thermal interface thickness and product lifespan.

[0042] Optionally, please refer to the following: Figure 3 and Figure 4 The resistance heating zone 121 is provided with a main resistance coil 122 and a secondary resistance coil 123.

[0043] The main resistance coil 122 bears the main heat power output, used to quickly bring the temperature control area close to the set temperature; the auxiliary resistance coil 123 can be used for edge compensation, local heating, constant temperature fine-tuning, or to work in conjunction with the main resistance coil 122. The partitioned arrangement of the main and auxiliary coils facilitates graded or zoned control based on temperature sensing results, compensating for differences in heat loss caused by ceramic edges, mounting areas, or cooling channels, thereby improving the temperature distribution of the working surface and providing a structural basis for controlling the temperature difference of the heating module within 3℃. The printed circuit board 12 of the resistance coil can be a double-sided circuit board. A double-sided circuit board refers to a circuit board where conductive lines are formed on both opposite surfaces of the insulating dielectric layer. The lines on both sides can be connected according to the circuit design through conductive structures, or they can form relatively independent heating circuits. By utilizing the wiring space on both sides of the circuit board, the effective resistance line length can be increased and the power density can be flexibly configured within a limited planar area, avoiding excessive congestion of single-sided lines or sudden changes in local linewidth.

[0044] Optionally, the main resistance coil 122 and the auxiliary resistance coil 123 are arranged in a serpentine pattern along the length of the resistance heating zone 121, and the auxiliary resistance coil 123 is located within the gap formed by the arrangement of the main resistance coil 122.

[0045] By using the serpentine arrangement of the main resistance coil 122 and the secondary resistance coil 123, and the specific positional relationship between the main resistance coil 122 and the secondary resistance coil 123, the surface temperature of the ceramic heat-conducting component 13 can be precisely controlled, thereby making the heat distribution more uniform and avoiding local overheating or overcooling.

[0046] Optionally, the line width of the main resistor coil 122 is 2 to 3 times the line width of the secondary resistor coil 123.

[0047] This limitation is to accommodate the significant difference in operating current between the main resistor coil 122 and the auxiliary resistor coil 123, ensuring that the high-current branch has sufficient current-carrying cross-sectional area, while avoiding excessively wide low-current branches that would waste space.

[0048] Optionally, the linewidth of the main resistor coil 122 is 6mil to 8mil, and the linewidth of the secondary resistor coil 123 is 2mil to 3.94mil.

[0049] Given that the resistivity, total coil length, and copper foil thickness are all determined, this linewidth limitation ensures that the resistance values ​​of the main resistor coil 122 or the auxiliary resistor coil 123 fall within their optimal ranges. Optionally, the insulation dielectric layer thickness of the resistor coil printed circuit board 12 is 0.07 mm to 0.10 mm.

[0050] A thinner insulating dielectric layer helps reduce the thermal resistance in the thickness direction of the printed circuit board 12 of the resistance coil, allowing for a shorter heat transfer distance between the resistance coils on both sides and the upper and lower heat-conducting structures. However, a dielectric thickness of 0.07~0.10 mm is still maintained, which balances insulation reliability, processing strength, and double-sided circuit stability.

[0051] Optionally, the resistance of the main resistor coil 122 is 3.5Ω~4.5Ω, and the resistance of the secondary resistor coil 123 is 5Ω~8Ω.

[0052] The main resistance coil 122 is primarily used for rapid temperature increase, while the secondary resistance coil 123 is mainly used for power compensation or fine temperature control. In this embodiment, the current through the main resistance coil 122 is 6A~8A, and the current through the secondary resistance coil 123 is 0.5A~1A. The high current excitation of the main resistance coil 122 rapidly generates Joule heat, achieving rapid temperature rise of the ceramic heat-conducting component 13. The secondary resistance coil 123 operates with a smaller current, precisely adjusting its heat generation to compensate for any localized temperature deviations that may occur with the main resistance coil 122, thereby achieving fine temperature control of the ceramic heat-conducting component 13 surface. After the main resistance coil 122 and the secondary resistance coil 123 work together to generate heat, the resulting heat is transferred to the surface of the ceramic heat-conducting component 13 via thermal conduction, enabling the ceramic heat-conducting component 13 to reach a temperature of 95°C within 1 minute and 30 seconds.

[0053] Optionally, the ceramic heat-conducting element 13 is an aluminum nitride ceramic sheet with a thermal conductivity of not less than 170 W / (m·K) and a thickness of 0.35 mm to 0.45 mm.

[0054] Aluminum nitride ceramics possess both high thermal conductivity and electrical insulation properties, providing a rapid, uniform, and electrically isolated heat transfer interface between the resistance heating zone 121 and the external heated object. A thickness of 0.35–0.45 mm reduces the thermal resistance in the thickness direction of the ceramic body, allowing heat to reach the working surface more quickly, while retaining the basic mechanical strength required for handling, positioning, and lamination.

[0055] Optionally, the ceramic heat-conducting component 13 is provided with an electroplated copper layer and a nickel-gold layer on the surface of the printed circuit board 12 away from the resistor coil.

[0056] The electroplated copper layer forms a thermally conductive and metallized transition layer on the surface of the ceramic heat conductor 13, which helps improve surface heat diffusion and subsequent interface bonding. The nickel-gold layer covering the electroplated copper layer can isolate the copper layer from the external environment, reduce oxidation and surface performance degradation, and help maintain surface stability. Through the synergistic effect of high thermal conductivity ceramics, surface metal layers, and thickness control, the temperature gradient inside and on the surface of the ceramic heat conductor 13 can be reduced, the speed of heat transfer to the target area can be increased, and the working surface temperature can be made more uniform.

[0057] Optionally, both the first thermally conductive adhesive layer 14 and the second thermally conductive adhesive layer 15 are formed by lamination and curing of a high thermally conductive prepreg without fiberglass cloth, and the thermal conductivity is not less than 3.0 W / (m·K).

[0058] The prepreg has a sheet-like shape that facilitates handling and positioning during the pre-stacking stage. Upon heating and pressure, its resin softens, flows, and fills the microscopic gaps between adjacent surfaces, subsequently cross-linking and curing to form a thermally conductive adhesive medium layer with bonding, insulation, and heat transfer functions. "Fiberglass-free" means that the prepreg does not use woven fiberglass cloth as a reinforcing skeleton. The absence of fiberglass cloth avoids localized thickness differences and resin flow obstruction caused by the warp and weft structure of the fabric, making it easier for the medium layer to adhere to the surfaces of the metal platform 112, the resistor coil printed circuit board 12, and the ceramic heat-conducting component 13, and also helps reduce voids.

[0059] The thermal conductivity of the two thermally conductive bonding dielectric layers is not less than 3.0 W / (m·K), ensuring that the dielectric layer maintains electrical insulation and structural bonding without becoming the main structure limiting thermal resistance. Placing the aforementioned dielectric layers on both sides of the circuit board creates a more balanced vertical thermal coupling relationship, facilitating heat transfer to the ceramic working surface and rapid heat transfer to the metal heat sink 11. This improves the temperature rise and fall response, enhances interface temperature uniformity, and reduces the risk of delamination due to localized stress concentration after long-term thermal cycling.

[0060] Adopting such Figure 1 The ceramic-metal hybrid printed circuit board 10 provided in the embodiment of this application was tested. The metal heat sink 11 is made of copper with a thermal conductivity ≥380W / (m·K) and a total thickness of 13.5mm. The metal base 111 has a thickness of 9mm, and the metal platform 112 has a thickness of 4.5mm. The resistor coil printed circuit board 12 is a double-sided circuit board with a main resistor coil 122 and a secondary resistor coil 123. The main resistor coil 122 has a resistance of 3.5Ω~4.5Ω, and the secondary resistor coil has a resistance of 5Ω~8Ω. The insulating dielectric layer on it has a thickness of 0.07mm~0.10mm. The ceramic heat conductor 13 is aluminum nitride ceramic with a thermal conductivity ≥170W / (m·K), a thickness of 0.38mm, and has copper and nickel-gold plating on its surface. The first thermally conductive adhesive dielectric layer 14 and the second thermally conductive adhesive dielectric layer 15 are both made of high thermal conductivity PP without glass cloth and have a thermal conductivity ≥3W / (m·K).

[0061] The experimental conditions were as follows: the uniformity of the temperature on the surface of the ceramic heat conductor 13 after the ceramic-metal hybrid printed circuit board 10 was heated to 95°C was tested under the conditions of 25°C (constant temperature), 40% RH, and normal atmospheric pressure (obtained by measuring the temperature difference between two areas with the largest average temperature difference selected arbitrarily on the ceramic heat conductor 13), and the time taken for the temperature of the ceramic heat conductor 13 to decrease from 95°C to 50°C.

[0062] The acceptance criteria are: uniformity <3℃, cooling time <1.2s.

[0063] Several ceramic-metal hybrid printed circuit boards 10 were selected for experiments. Taking the test results of four ceramic-metal hybrid printed circuit boards 10 as examples, the experimental simulation results are as follows: Figures 5 to 8 As shown in the figure, the experimental data are shown in the table below.

[0064]

[0065] Depend on Figures 5 to 8 As can be seen from the above experimental data, the ceramic-metal hybrid printed circuit board 10 provided in this application embodiment significantly improves the energy efficiency of the product, the heat dissipation speed of the ceramic heat conductor 13 is increased to 30~50℃ / second, and the uniformity is significantly improved. Figures 5 to 8 The more uniform the color of the area corresponding to the resistance heating zone, the better the uniformity.

[0066] As shown in the table above, this embodiment uses data from experimental piece 1 for verification. The heat dissipation rate of the ceramic heat-conducting component 13 is calculated as follows: the highest average surface temperature is taken, and the time required for the temperature to drop to 50°C is taken as the cooling time. In this case, 50°C is used as the termination temperature, and the highest average temperature is subtracted from 50°C and then divided by the corresponding cooling time. The verification results show that the heat dissipation rate of the ceramic heat-conducting component 13 is 48.112°C / second, which meets the improvement requirement of 30~50°C / second.

[0067] It is understandable that the surface temperature of the ceramic heat-conducting component 13 can be reduced to 55℃. The heat dissipation rate is calculated based on the heat dissipation time of the ceramic heat-conducting component 13 when its surface temperature drops to 55℃ (this data is not shown in the table above). The results all fall within the range of heat dissipation rate of 30-50℃ / second.

[0068] In another aspect of the embodiments of this application, a testing device is provided, including a ceramic-metal hybrid printed circuit board 10 as described in any of the preceding claims.

[0069] The testing device has the same structure and beneficial effects as the ceramic-metal hybrid printed circuit board 10 in the foregoing embodiments. The structure and beneficial effects of the ceramic-metal hybrid printed circuit board 10 have been described in detail in the foregoing embodiments and will not be repeated here.

[0070] The above description is merely an optional embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A ceramic-metal hybrid printed circuit board, characterized in that, include: A metal heat sink has a metal base and a metal platform protruding to one side from the metal base; A printed circuit board for the resistance coil is stacked on the laminated surface of the metal platform; A ceramic heat-conducting component is stacked on the side of the printed circuit board of the resistance coil away from the metal platform; A first thermally conductive adhesive layer and a second thermally conductive adhesive layer are respectively located on both sides of the printed circuit board of the resistor coil. The first thermally conductive adhesive layer laminates the printed circuit board of the resistor coil to the metal platform, and the second thermally conductive adhesive layer laminates the printed circuit board of the resistor coil to the ceramic thermally conductive component. The resistor coil printed circuit board has a resistance heating area, and the resistance heating area, the metal platform, and the ceramic heat-conducting component at least partially overlap along the thickness direction of the ceramic-metal hybrid printed circuit board.

2. The ceramic-metal hybrid printed circuit board as described in claim 1, characterized in that, The metal platform has a lamination groove on the surface away from the metal base. The resistor coil printed circuit board, the first thermally conductive adhesive medium layer and the second thermally conductive adhesive medium layer are all located in the lamination groove. The surface of the second thermally conductive adhesive medium layer away from the resistor coil printed circuit board is flush with the groove opening of the lamination groove.

3. The ceramic-metal hybrid printed circuit board as described in claim 1, characterized in that, The resistance heating zone is equipped with a main resistance coil and a secondary resistance coil.

4. The ceramic-metal hybrid printed circuit board as described in claim 3, characterized in that, The main resistance coil and the secondary resistance coil are arranged in a serpentine pattern along the length of the resistance heating zone, and the secondary resistance coil is located within the gap formed by the arrangement of the main resistance coil.

5. The ceramic-metal hybrid printed circuit board as described in claim 3, characterized in that, The linewidth of the main resistor coil is 2 to 3 times the linewidth of the secondary resistor coil.

6. The ceramic-metal hybrid printed circuit board as described in claim 5, characterized in that, The linewidth of the main resistor coil is 6mil to 8mil, and the linewidth of the secondary resistor coil is 2mil to 3.94mil.

7. The ceramic-metal hybrid printed circuit board as described in claim 3, characterized in that, The resistance of the main resistor coil is 3.5Ω to 4.5Ω, and the resistance of the secondary resistor coil is 5Ω to 8Ω.

8. The ceramic-metal hybrid printed circuit board as described in claim 1, characterized in that, Both the first thermally conductive adhesive medium layer and the second thermally conductive adhesive medium layer are formed by lamination and curing of high thermal conductivity semi-cured sheets without fiberglass cloth, and the thermal conductivity is not less than 3.0 W / (m·K).

9. The ceramic-metal hybrid printed circuit board as described in claim 1, characterized in that, The metal base is a copper base, the metal platform is a copper platform, and the thermal conductivity of the metal base and the metal platform is ≥380W / (m·K).

10. The ceramic-metal hybrid printed circuit board as described in claim 1, characterized in that, The total thickness of the metal base and the metal platform is 13mm~15mm, the thickness of the metal base is 9mm~10mm, and the thickness of the metal platform is 4mm~5mm.

11. The ceramic-metal hybrid printed circuit board as described in claim 1, characterized in that, The ceramic heat-conducting component is an aluminum nitride ceramic sheet, which has a thermal conductivity of not less than 170 W / (m·K) and a thickness of 0.35 mm to 0.45 mm.

12. The ceramic-metal hybrid printed circuit board as described in claim 1, characterized in that, The ceramic heat-conducting component has an electroplated copper layer and a nickel-gold layer sequentially on the surface of the printed circuit board opposite to the resistor coil.

13. The ceramic-metal hybrid printed circuit board as described in claim 3, characterized in that, The thickness of the insulating dielectric layer on the printed circuit board of the resistor coil is 0.07mm~0.10mm.

14. A testing device, characterized in that, Including ceramic-metal hybrid printed circuit boards as described in any one of claims 1 to 13.

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