An insulated wiring board

Abstract

The application discloses an insulating circuit board, which comprises an upper metal layer, a ceramic substrate layer and a lower metal layer arranged from top to bottom. The ceramic substrate layer is provided with a groove on the side close to the upper metal layer and is provided with a containing hole on the side close to the lower metal layer. The groove and the containing hole are non-penetratingly arranged on the ceramic substrate layer. At least a part of the upper metal layer extends into the groove, and at least a part of the lower metal layer extends into the containing hole. The upper metal layer comprises one or more layers of a tin gold alloy layer, a platinum gold layer, a first gold layer, a first nickel layer, a first copper layer and a titanium layer. The lower metal layer comprises one or more layers of a second copper layer, a second nickel layer and a second gold layer. The groove and the containing hole arranged on the ceramic substrate layer are beneficial to accommodating high-thermal-conductivity materials, thereby enhancing the thermal conductivity of the ceramic substrate layer and the heat dissipation performance of the insulating circuit board, and further increasing the use stability.

Description

Technical Field

[0001] This application relates to the field of ceramic substrate technology, and more particularly to an insulating circuit board. Background Technology

[0002] Insulated circuit boards (PCBs) are indispensable core components in modern electronic devices. Composed of an insulating substrate and conductive patterns, they primarily serve to achieve electrical connections and mechanical support between electronic components. PCBs are manufactured using a copper-clad laminate etching process, with copper foil covering the surface to form conductors or wiring. These conductors connect the electronic components, enabling signal transmission and power supply. PCBs not only reduce the space occupied by conductors but also improve the integration and performance of electronic devices through a clear layout and organization of the conductors.

[0003] Currently, with the advancement of technology and the ever-increasing performance requirements of electronic devices, as well as the rapid development of microelectronics integration technology, the requirements for the quality and performance of insulated circuit boards (PCBs) are becoming increasingly stringent. Among these, insulated circuit boards are attracting growing market attention due to their excellent thermal conductivity and low dielectric loss. These characteristics give insulated circuit boards significant advantages in applications requiring efficient thermal management and signal integrity. For example, in 5G communication equipment, insulated circuit boards can significantly improve signal processing and transmission speed, further enhancing data transmission performance and efficiency. Therefore, they are widely used in fields such as laser pumping and AI applications.

[0004] However, as the application of insulated circuit boards in high power density devices becomes more widespread, the demand for heat dissipation performance of insulated circuit boards is also gradually increasing. Understandably, developing an insulated circuit board with good thermal conductivity to enhance heat dissipation performance has become one of the urgent problems to be solved in the industry. Utility Model Content

[0005] One objective of this application is to provide an insulating circuit board that improves the thermal conductivity and further enhances the heat dissipation performance of the insulating circuit board.

[0006] Another objective of this application is to provide an insulated circuit board that enhances the performance, stability, and service life of the insulated circuit board.

[0007] To achieve the above objectives, the technical solution adopted in this application is as follows: an insulating circuit board, comprising an upper metal layer, a ceramic substrate layer, and a lower metal layer disposed from top to bottom. The ceramic substrate layer has a groove on the side near the upper metal layer and an accommodating hole on the side near the lower metal layer. The groove and the accommodating hole are disposed non-through the ceramic substrate layer. At least a portion of the upper metal layer extends into the groove, and at least a portion of the lower metal layer extends into the accommodating hole. The upper metal layer includes one or more layers selected from a tin-gold alloy layer, a platinum layer, a first gold layer, a first nickel layer, a first copper layer, and a titanium layer. The lower metal layer includes one or more layers selected from a second copper layer, a second nickel layer, and a second gold layer.

[0008] In some embodiments, the depth of the groove along the first direction is 0.05mm to 0.25mm, the depth of the receiving hole along the first direction is 0.05mm to 0.25mm, the length of the groove along the second direction is less than the length of the ceramic substrate layer along the second direction, the width of the groove along the third direction is 0.010mm to 0.9mm, and the second direction and the third direction are perpendicular to the first direction.

[0009] In some embodiments, the depth of the groove along the first direction is 0.055mm to 0.065mm, and the depth of the receiving hole along the first direction is 0.055mm to 0.065mm.

[0010] In some embodiments, the upper metal layer includes a first metal portion and a second metal portion arranged side by side, the first metal portion and the second metal portion being spaced apart from each other along a third direction.

[0011] In some embodiments, the distance between the first metal portion and the second metal portion along a third direction is 0.05μm to 0.07μm, the first metal portion is opposite to the groove, and at least a portion of the bottom surface of the first metal portion extends into the groove.

[0012] In some embodiments, the upper metal layer includes, from top to bottom, a tin-gold alloy layer, a platinum layer, a first gold layer, a first nickel layer, a first copper layer, and a titanium layer, wherein the thickness of the tin-gold alloy layer is 2 μm to 5 μm, the thickness of the platinum layer is 0.1 μm to 3 μm, the thickness of the first gold layer is 0.3 μm to 3 μm, the thickness of the first nickel layer is 1 μm to 4 μm, the thickness of the first copper layer is 20 μm to 100 μm, and the thickness of the titanium layer is 0.05 μm to 5 μm; the lower metal layer includes, from top to bottom, a second copper layer, a second nickel layer, and a second gold layer, wherein the thickness of the second gold layer is 0.3 μm to 3 μm, the thickness of the second nickel layer is 1 μm to 4 μm, and the thickness of the second copper layer is 20 μm to 100 μm.

[0013] In some embodiments, the thickness of the tin-gold alloy layer is 3μm to 4.5μm, the thickness of the platinum layer is 0.3μm to 3μm, the thickness of the first gold layer is 0.5μm to 1.8μm, the thickness of the first nickel layer is 1μm to 2μm, the thickness of the first copper layer is 60μm to 90μm, the thickness of the titanium layer is 0.05μm to 0.2μm, the thickness of the second gold layer is 0.5μm to 1.8μm, the thickness of the second nickel layer is 2μm to 3μm, and the thickness of the second copper layer is 61μm to 91μm.

[0014] In some embodiments, the receiving hole is circular, or closed arc-shaped, or polygonal.

[0015] In some embodiments, the depth of the groove along the first direction is 0.055mm to 0.065mm, and the depth of the receiving hole along the first direction is 0.055mm to 0.065mm.

[0016] In some embodiments, the insulating circuit board further includes a chip layer, the chip layer and the upper metal layer being bonded to each other on the side away from the lower metal layer, and the projection of the groove along a first direction falling completely into the projection of the chip layer along the first direction.

[0017] Compared with the prior art, the beneficial effects of this application are as follows: (1) By providing grooves and accommodating holes on the ceramic substrate layer in the insulating circuit board, it is beneficial to accommodate high thermal conductivity materials, thereby enhancing the thermal conductivity of the ceramic substrate layer, thereby enhancing the heat dissipation performance of the insulating circuit board, reducing the risk of device overheating failure due to overheating during use, and further increasing the stability of use.

[0018] (2) By providing protruding mating parts and assembly parts in the insulating circuit board that can fit together with the groove and the receiving hole, the bonding force between the layers is increased, the stability of use is further enhanced, and the reliability of the insulating circuit board is improved. Attached Figure Description

[0019] Figure 1A This is a top view of an insulated circuit board according to this application.

[0020] Figure 1B yes Figure 1A A cross-sectional view along direction A.

[0021] Figure 2 This is a bottom view of an insulated circuit board according to this application.

[0022] Figure 3 This is a three-dimensional schematic diagram of the layered structure of an insulating circuit board according to this application (chip layers are not shown).

[0023] Figure 4 This is a schematic diagram of the layered structure of an insulating circuit board according to this application.

[0024] Figure 5 This is a schematic diagram of a partial layered structure of an insulating circuit board according to this application.

[0025] In the figure: 1. Insulating circuit board; 10. Ceramic substrate layer; 11. Groove; 12. Accommodating hole; 20. Upper metal layer; 201. First metal part; 202. Second metal part; 21. Protruding mating part; 30. Lower metal layer; 31. Assembly part; 40. Chip layer. Detailed Implementation

[0026] The present application will be further described below with reference to specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0027] As used herein, the terms “prepared from” and “comprising” are synonymous. The terms “comprising,” “including,” “having,” “containing,” or any other variation thereof, as used herein, are intended to cover non-exclusive inclusion. For example, a composition, step, method, article, or apparatus that includes the listed elements is not necessarily limited to those elements and may include other elements not expressly listed or elements inherent to such composition, step, method, article, or apparatus.

[0028] When a quantity, concentration, or parameter is expressed as a range, a preferred range, or a range defined by a series of upper and lower preferred values, this should be understood as specifically disclosing any pair of any upper or preferred value with any lower or preferred value, regardless of whether the range is disclosed individually. For example, when the range is disclosed as “1 to 5”, the described range should be interpreted as including ranges “1 to 4”, “1 to 3”, “1 to 2 and 4 to 5”, “1 to 3 and 5”, etc. When numerical ranges are described herein, unless otherwise stated, the range includes its endpoints and all integers and fractions within that range.

[0029] Approximate terms used in the specification and claims to modify quantities indicate that the invention is not limited to that specific quantity, but also includes acceptable modifications close to that quantity that do not alter the relevant essential function. Correspondingly, the use of "about," "approximately," etc., to modify a numerical value means that the invention is not limited to that precise value. In some instances, approximate terms may correspond to the precision of the instrument used to measure the value. In this application's specification and claims, scope definitions can be combined and / or interchanged, unless otherwise stated, these scopes include all subscopes contained therein.

[0030] To achieve the above objectives, such as Figure 1A , Figure 1B ,as well as Figures 2-5 As shown, the technical solution adopted in this application is as follows: an insulating circuit board 1 includes an upper metal layer 20, a ceramic substrate layer 10, and a lower metal layer 30 disposed from top to bottom. The ceramic substrate layer 10 has a groove 11 on the side near the upper metal layer 20 and a receiving hole 12 on the side near the lower metal layer 30. The groove 11 and the receiving hole 12 are non-penetratingly disposed in the ceramic substrate layer 10. At least a portion of the upper metal layer 20 extends into the groove 11, and at least a portion of the lower metal layer 30 extends into the receiving hole 12. By providing the groove 11 and the receiving hole 12 on the ceramic substrate layer 10, it is beneficial to accommodate high thermal conductivity materials, thereby enhancing the thermal conductivity of the ceramic substrate layer 10 and thus enhancing the heat dissipation performance of the insulating circuit board 1. Further, the upper metal layer 20 includes one or more layers selected from a tin-gold alloy layer, a platinum layer, a first gold layer, a first nickel layer, a first copper layer, and a titanium layer, and the lower metal layer 30 includes one or more layers selected from a second copper layer, a second nickel layer, and a second gold layer. It is worth mentioning that tin-gold alloy, platinum, gold, nickel, copper, and titanium, as materials with high thermal conductivity, can enhance the thermal conductivity of the insulating circuit board 1, which is beneficial for heat dissipation. On the other hand, since the lower metal layer 30 includes a second gold layer, a second nickel layer, and a second copper layer, it is worth mentioning that the good thermal conductivity of the metals due to the inclusion of gold, nickel, and copper can effectively enhance the heat dissipation performance of the insulating circuit board 1.

[0031] In some embodiments, reference Figure 4 It is understood that the ceramic substrate layer 10 has a groove 11 on the side near the upper metal layer 20 and a receiving hole 12 on the side near the lower metal layer 30; the upper metal layer 20 has a protruding mating portion 21 on the side near the ceramic substrate layer 10, and the protruding mating portion 21 fills the groove 11; the lower metal layer 30 has an assembly portion 31 on the side near the ceramic substrate layer 10, and the assembly portion 31 fills the receiving hole 12. It can be understood that since the protruding mating portion 21 in the upper metal layer 20 can fill into the groove 11 and the assembly portion 31 in the lower metal layer 30 can fill into the receiving hole 12, the interlayer bonding is tighter and it is beneficial to improve the thermal conductivity of the insulating circuit board 1.

[0032] In some embodiments, the upper metal layer 20 and the lower metal layer 30 are disposed on opposite sides of the ceramic substrate layer 10 along a first direction without contact. It is worth noting that since the upper metal layer 20 does not contact the lower metal layer 30, this not only improves the mechanical properties of the ceramic substrate layer 10 but also prevents damage to the ceramic substrate layer 10 or even the insulating circuit board 1 caused by the metal extending into the through-hole and being heated when high-thermal-expansion metal materials are used in the upper metal layer 20 and the lower metal layer 30. This enhances the service life and operational stability of the insulating circuit board 1.

[0033] In some embodiments, the depth of the groove 11 along the first direction is 0.05mm to 0.25mm. It is understood that the depth of the groove 11 along the first direction is 0.05mm, 0.1mm, 0.15mm, 0.2mm, or 0.25mm. More preferably, the depth of the groove 11 along the first direction is 0.055mm to 0.065mm. The depth of the receiving hole 12 along the first direction is 0.05mm to 0.25mm. It is understood that the depth of the receiving hole 12 along the first direction is 0.05mm, 0.1mm, 0.15mm, 0.2mm, or 0.25mm. More preferably, the depth of the receiving hole 12 along the first direction is 0.055mm to 0.065mm. The length of the groove 11 along the second direction is less than the length of the ceramic substrate layer 10 along the second direction. The width of the groove 11 along the third direction is 0.01mm to 0.9mm. It can be understood that the width of the groove 11 along the third direction is 0.01mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, or 0.9mm. Further, the width of the groove 11 along the third direction is 0.1mm to 0.6mm. It should be understood that the second and third directions are perpendicular to the first direction. The coordinate system can be flexibly set according to actual needs and is not limited here.

[0034] It is worth mentioning that since various materials that are conducive to heat conduction can be set in the groove 11, it is beneficial to enhance the adaptability of the ceramic substrate layer 10 in various application environments. Furthermore, when the ceramic substrate layer 10 provided in this application is applied to the insulating circuit board 1, the improved thermal conductivity can enhance the heat dissipation performance of the insulating circuit board 1, thereby maintaining good stability in use and extending its service life.

[0035] Wherein, the first direction is the height direction of the ceramic substrate layer 10, the second direction is the length direction of the ceramic substrate layer 10, and the third direction is the width direction of the ceramic substrate layer 10. It can be understood that the coordinate system can be flexibly set according to actual needs, and there are no restrictions here.

[0036] In some embodiments, the upper metal layer 20 includes a first metal portion 201 and a second metal portion 202 arranged side by side, with the first metal portion 201 and the second metal portion 202 spaced apart from each other. The spaced arrangement of the first metal portion 201 and the second metal portion 202 helps to increase the adaptability of the insulating circuit board 1 in various application environments and avoids the risk of damage to the insulating circuit board 1 due to thermal expansion.

[0037] In some embodiments, reference Figure 1A as well as Figure 1B It is known that the first metal part 201 is provided with a protruding mating part 21, which extends into the groove 11 in the ceramic substrate layer 10, thereby further enhancing the bonding stability between the first metal part 201 and the ceramic substrate layer 10.

[0038] In some embodiments, the distance between the first metal portion 201 and the second metal portion 202 along a third direction is 0.05 μm to 0.07 μm. It is understood that the distance between the first metal portion 201 and the second metal portion 202 along a third direction can be 0.05 μm, 0.055 μm, 0.06 μm, 0.065 μm, or 0.07 μm. Further, the distance between the first metal portion 201 and the second metal portion 202 along a third direction is 0.055 μm to 0.065 μm. The first metal portion 201 is opposite to the groove 11, and at least a portion of the bottom surface of the first metal portion 201 extends into the groove 11. It is worth noting that when the distance between the first metal portion 201 and the second metal portion 202 along a third direction is too small, the heat dissipation performance of the insulating circuit board 1 will be reduced.

[0039] It is understandable that the thermal conductivity of the current ceramic substrate layer 10 is insufficient to meet the growing demand for heat dissipation performance. However, the ceramic substrate layer 10 has the advantage of low cost. Therefore, this application improves the ceramic substrate layer 10 by providing a ceramic substrate layer 10 with a groove 11 and a receiving hole 12. However, it is difficult to achieve good heat dissipation performance by using the ceramic substrate layer 10 alone in a device. Therefore, it is necessary to add an upper metal layer 20 and a lower metal layer 30 on both sides of the ceramic substrate layer 10 to improve thermal conductivity, thereby obtaining an insulating circuit board 1 with good heat dissipation performance and usability.

[0040] It is worth mentioning that the upper metal layer 20 and the lower metal layer 30 can be disposed on both sides of the ceramic substrate layer 10 by deposition sputtering or electroplating. Deposition sputtering or electroplating, in particular, enhances the adhesion between the upper metal layer 20, the lower metal layer 30, and the ceramic substrate layer 10. On one hand, since deposition sputtering or electroplating allows for the integral molding of the upper metal layer 20 and the lower metal layer 30, the mechanical properties of the upper metal layer 20 and the lower metal layer 30 are enhanced. On the other hand, since the protruding mating portion 21 and the mounting portion 31 are integrally molded, they can be tightly bonded to the ceramic substrate layer 10, further improving the stability of the insulating circuit board 1 in use. Further, refer to Figure 1~ Figure 2 It is known that a smooth insulating circuit board 1 can be obtained by deposition sputtering or electroplating, and multiple metal layers can be set in the upper metal layer 20 and the lower metal layer 30 to enhance the performance.

[0041] In some embodiments, the components of each layer in the first metal part 201 and the second metal part 202 are the same, and the thickness of the same layer is also the same, which further increases the stability of the insulating circuit board 1 in use.

[0042] In some embodiments, the upper metal layer 20 includes, from top to bottom, a tin-gold alloy layer, a platinum layer, a first gold layer, a first nickel layer, a first copper layer, and a titanium layer, wherein the thickness of the platinum layer is 0.1 μm to 3 μm, specifically, the thickness of the platinum layer is 0.1 μm, 0.5 μm, 1 μm, 1.5 μm, 2 μm, 2.5 μm, and 3 μm, and more preferably, the thickness of the platinum layer is 0.3 μm to 3 μm. It is understood that the platinum layer enhances the stability and performance of the insulating circuit board 1 while simultaneously improving its mechanical properties.

[0043] In some embodiments, the thickness of the first gold layer is 0.3 μm to 3 μm, specifically, the thickness of the first gold layer is 0.3 μm, 0.5 μm, 1 μm, 1.1 μm, 1.5 μm, 2 μm, 2.5 μm, or 3 μm, and more preferably, the thickness of the first gold layer is 0.5 μm to 1.8 μm. The thickness of the first nickel layer is 1 μm to 4 μm, specifically, the thickness of the first nickel layer is 1 μm, 1.5 μm, 2 μm, 2.5 μm, 3 μm, or 4 μm, and more preferably, the thickness of the first nickel layer is 1 μm to 2 μm. The thickness of the first copper layer is 20 μm to 100 μm, specifically, the thickness of the first copper layer is 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 75 μm, 80 μm, 90 μm, or 100 μm, and more preferably, the thickness of the first copper layer is 60 μm to 90 μm. The thickness of the titanium layer is 0.05 μm to 0.2 μm, specifically, the thickness of the titanium layer is 0.05 μm, 0.1 μm, 0.15 μm, and 0.2 μm. The thickness of the tin-gold alloy layer is 2 μm to 5 μm, and more preferably, the thickness of the tin-gold alloy layer is 3 μm to 4.5 μm. Since the thickness of the upper metal layer 20 in the insulating circuit board 1 directly affects its conductivity and thermal conductivity, the selection of the thickness of each metal layer in the insulating circuit board 1 is crucial for ensuring the performance, reliability, environmental adaptability, and heat dissipation performance of the circuit, and is also a key parameter that needs to be precisely controlled in the design and manufacturing of the insulating circuit board 1.

[0044] In some embodiments, the lower metal layer 30 includes a second copper layer, a second nickel layer, and a second gold layer disposed sequentially from top to bottom. The thickness of the second gold layer is 0.3 μm to 3 μm, more preferably 0.5 μm to 1.8 μm. The thickness of the second nickel layer is 1 μm to 4 μm, more preferably 2 μm to 3 μm. The thickness of the second copper layer is 20 μm to 100 μm, more preferably 61 μm to 91 μm. It is worth noting that the good thermal conductivity of the gold, nickel, and copper layers effectively enhances the heat dissipation performance of the insulating circuit board 1.

[0045] In some embodiments, the receiving hole 12 is circular, closed arc-shaped, or polygonal. By providing various receiving holes 12, the bonding performance between layers can be increased during adhesion, thereby enhancing stability in use.

[0046] In some embodiments, reference Figure 4 and Figure 5As can be seen, the insulating circuit board 1 further includes a chip layer 40, which is bonded to the upper metal layer 20 on the side away from the lower metal layer 30. The projection of the groove 11 along the first direction completely falls inside the projection of the chip layer 40 along the first direction. It is understood that the chip layer 40, as one of the important components in the insulating circuit board 1, exhibits significant heat generation, especially when used in high-performance processors, power semiconductors, and other electronic devices. Therefore, to enhance the stability of the insulating circuit board 1, heat dissipation of the chip layer 40 is necessary. In this application, by placing the groove 11, which can accommodate highly thermally conductive material to enhance heat dissipation performance, below the chip layer 40 along the first direction, the heat generated by the chip layer 40 can be conducted away promptly and quickly, thereby enhancing the performance of the insulating circuit board 1.

[0047] The basic principles, main features, and advantages of this application have been described above. Those skilled in the art should understand that this application is not limited to the above embodiments. The embodiments and descriptions in the specification are merely the principles of this application. Various changes and modifications can be made to this application without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection claimed by this application is defined by the appended claims and their equivalents.

Claims

1. An insulating circuit board, characterized in that, The device comprises an upper metal layer, a ceramic substrate layer, and a lower metal layer arranged from top to bottom. The ceramic substrate layer has a groove on the side near the upper metal layer and a receiving hole on the side near the lower metal layer. The groove and the receiving hole are non-penetratingly disposed in the ceramic substrate layer. At least a portion of the upper metal layer extends into the groove, and at least a portion of the lower metal layer extends into the receiving hole. The upper metal layer includes one or more layers selected from tin-gold alloy layer, platinum layer, first gold layer, first nickel layer, first copper layer, and titanium layer. The lower metal layer includes one or more layers selected from second copper layer, second nickel layer, and second gold layer.

2. The insulating circuit board according to claim 1, characterized in that, The groove has a depth of 0.05mm to 0.25mm along the first direction, the receiving hole has a depth of 0.05mm to 0.25mm along the first direction, the length of the groove along the second direction is less than the length of the ceramic substrate layer along the second direction, the width of the groove along the third direction is 0.010mm to 0.9mm, and the second direction and the third direction are perpendicular to the first direction.

3. The insulating circuit board according to claim 2, characterized in that, The groove has a depth of 0.055mm to 0.065mm along the first direction, and the receiving hole has a depth of 0.055mm to 0.065mm along the first direction.

4. The insulating circuit board according to claim 1, characterized in that, The upper metal layer includes a first metal part and a second metal part arranged side by side, the first metal part and the second metal part being spaced apart from each other along a third direction.

5. The insulating circuit board according to claim 4, characterized in that, The distance between the first metal part and the second metal part along a third direction is 0.05μm to 0.07μm. The first metal part is opposite to the groove, and at least a portion of the bottom surface of the first metal part extends into the groove.

6. The insulating circuit board according to any one of claims 1-5, characterized in that, The upper metal layer comprises, from top to bottom, a tin-gold alloy layer, a platinum layer, a first gold layer, a first nickel layer, a first copper layer, and a titanium layer. The thickness of the tin-gold alloy layer is 2μm to 5μm, the thickness of the platinum layer is 0.1μm to 3μm, the thickness of the first gold layer is 0.3μm to 3μm, the thickness of the first nickel layer is 1μm to 4μm, the thickness of the first copper layer is 20μm to 100μm, and the thickness of the titanium layer is 0.05μm to 5μm. The lower metal layer comprises, from top to bottom, a second copper layer, a second nickel layer, and a second gold layer. The thickness of the second gold layer is 0.3μm to 3μm, the thickness of the second nickel layer is 1μm to 4μm, and the thickness of the second copper layer is 20μm to 100μm.

7. The insulating circuit board according to claim 6, characterized in that, The thickness of the tin-gold alloy layer is 3μm~4.5μm, the thickness of the platinum layer is 0.3μm~3μm, the thickness of the first gold layer is 0.5μm~1.8μm, the thickness of the first nickel layer is 1μm~2μm, the thickness of the first copper layer is 60μm~90μm, the thickness of the titanium layer is 0.05μm~0.2μm, the thickness of the second gold layer is 0.5μm~1.8μm, the thickness of the second nickel layer is 2μm~3μm, and the thickness of the second copper layer is 61μm~91μm.

8. The insulating circuit board according to any one of claims 1-5, characterized in that, The receiving hole is circular, closed arc-shaped, or polygonal.

9. The insulating circuit board according to any one of claims 1-5, characterized in that, The insulating circuit board further includes a chip layer, the chip layer and the upper metal layer are bonded to each other on the side away from the lower metal layer, and the projection of the groove along the first direction falls completely into the projection of the chip layer along the first direction.

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