Pre-molded direct copper clad substrate and method of making same
By introducing a pre-encapsulation layer with a suitable coefficient of thermal expansion between the copper layer and the ceramic substrate, the problems of copper layer warping and stress concentration are solved, improving the reliability and durability of direct copper-clad laminates.
Patent Information
- Application Number
- CN202310811812.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-07-04
- Publication Date
- 2025-01-07
AI Technical Summary
Existing direct copper-clad laminates suffer from significant differences in the coefficients of thermal expansion between the copper layer and the ceramic substrate, leading to copper layer warping and stress concentration, which reduces the reliability and durability of the substrate.
A pre-molded direct copper-clad substrate is designed by introducing a pre-encapsulation layer with a thermal expansion coefficient between the copper layer and the ceramic substrate, and forming the pre-encapsulation layer under specific conditions to avoid copper layer warping and stress concentration.
It effectively improves the reliability and durability of the substrate, reduces copper layer warpage and stress concentration, and enhances the overall performance of the substrate.
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Figure CN119275198A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to a direct copper clad substrate, and more particularly to a pre-molded direct copper clad substrate and a manufacturing method thereof. Background Art
[0002] The difference in coefficient of thermal expansion (CTE) between the copper layer and the ceramic plate of the existing direct bonded copper (DBC) substrate is too large, so the copper layer is easily affected by temperature changes, causing warping of the copper layer or stress concentration on the ceramic plate, thereby reducing the reliability and durability of the existing direct bonded copper substrate.
[0003] Therefore, the applicant believes that the above defects can be improved, and has devoted himself to research and applied scientific principles, and finally proposed an application that is reasonably designed and effectively improves the above defects. Summary of the invention
[0004] The present application provides a pre-molded direct copper clad substrate and a manufacturing method thereof, which can effectively improve the defects that may occur in the existing direct copper clad substrate.
[0005] The present application discloses a pre-molded direct copper-clad substrate, which includes: a ceramic plate having a first plate surface, a second plate surface located on the opposite side of the first plate surface, and a ring side surface connected to the first plate surface and the second plate surface; a first copper layer, which is eutectic bonded to the first plate surface; wherein the first copper layer has a bonding surface away from the first plate surface, and a part of the first plate surface does not contact the first copper layer and is defined as a configuration area; a second copper layer, which is eutectic bonded to the second plate surface; wherein the volume of the first copper layer is less than 80% of the volume of the second copper layer; and a pre-packaging layer, which is molded in the configuration area and covers the first copper layer so that at least a part of the bonding surface of the first copper layer is exposed outside the pre-packaging layer; wherein the thermal expansion coefficient of the pre-packaging layer is between the thermal expansion coefficient of the ceramic plate and the thermal expansion coefficient of the first copper layer; wherein the pre-packaging layer has a top edge and a ring side edge connected to the top edge, and the top edge is not lower than the bonding surface of the first copper layer relative to the first plate surface, and the ring side edge is flush with the ring side surface of the ceramic plate.
[0006] Optionally, the first copper layer includes: a plurality of inner copper pads spaced apart from each other; and a plurality of outer copper pads spaced apart around the outer sides of the plurality of inner copper pads, and the plurality of outer copper pads spaced apart from each other and arranged in a ring shape.
[0007] Optionally, among two edges of the plurality of inner copper pads facing each other, at least one protrusion is formed on one edge, and at least one groove is formed on the other edge to accommodate a portion of the at least one protrusion.
[0008] Optionally, the edges of the plurality of inner copper pads and the inner edges of the plurality of outer copper pads are all in a stepped structure and are buried in the pre-packaging layer.
[0009] Optionally, at least one of the top edge and the ring side edge of the pre-packaging layer is formed with a centerline average roughness of at least 0.8 micrometers.
[0010] Optionally, a top edge of the pre-packaging layer is coplanar with a bonding surface of the first copper layer.
[0011] Optionally, the pre-packaging layer includes: a coating body formed in the configuration area and coating the first copper layer; and a bracket body extending from the coating body and protruding from the joint surface, and the bracket body has a top edge; wherein the bracket body covers a portion of the joint surface.
[0012] Optionally, the top edge of the bracket body is spaced from the joint surface by a distance of no more than 100 microns, and the bracket body and the joint surface surround a plurality of accommodating grooves; wherein the second copper layer is used to connect to a heat sink.
[0013] The present application also discloses a method for manufacturing a pre-molded direct copper-clad substrate, which includes: a pre-step: providing a ceramic plate having a first plate surface, a second plate surface located on the opposite side of the first plate surface, and a ring side surface connected to the first plate surface and the second plate surface; a copper-cladding step: forming a first copper layer eutectic-bonded with the first plate surface of the ceramic plate; wherein the first copper layer has a bonding surface away from the first plate surface, and a part of the first plate surface does not contact the first copper layer and is defined as a configuration area; a plasma cleaning step: cleaning the ceramic plate and the first copper layer; and a pre-packaging step: molding a pre-packaging layer in the configuration area so that the pre-packaging layer covers the first copper layer, and at least a part of the bonding surface is exposed outside the pre-packaging layer; wherein the thermal expansion coefficient of the pre-packaging layer is between the thermal expansion coefficient of the ceramic plate and the thermal expansion coefficient of the first copper layer.
[0014] Optionally, in the copper coating step, a second copper layer eutectically bonded to the second surface of the ceramic plate is further formed on the second surface of the ceramic plate, and the volume of the first copper layer is less than 80% of the volume of the second copper layer.
[0015] Optionally, after the pre-packaging step, the method for manufacturing a pre-molded direct copper-bonded substrate further comprises a roughening step: forming a centerline average roughness of at least 0.8 micrometers on at least one of the top edge and the side edge of the pre-packaging layer.
[0016] Optionally, in the pre-packaging step, the pre-packaging layer has a top edge and a ring side edge connected to the top edge, and the top edge is not lower than the bonding surface of the first copper layer relative to the first board surface, and the ring side edge is flush with the ring side surface of the ceramic plate.
[0017] Optionally, in the pre-packaging step, a top edge of the pre-packaging layer is coplanar with a bonding surface of the first copper layer.
[0018] Optionally, in the pre-packaging step, the pre-packaging layer protrudes from the bonding surface and covers a portion of the bonding surface, so that the pre-packaging layer and the bonding surface surround a plurality of accommodating grooves; wherein the top edge of the pre-packaging layer is spaced from the bonding surface by a distance not greater than 100 microns.
[0019] The present application further discloses a pre-molded direct copper-clad substrate, which includes: a ceramic plate having a first plate surface, a second plate surface located on the opposite side of the first plate surface, and a ring side surface connected to the first plate surface and the second plate surface; a first copper layer, which is eutectic bonded to the first plate surface; wherein the first copper layer has a bonding surface away from the first plate surface, and a portion of the first plate surface does not contact the first copper layer and is defined as a configuration area, and the ceramic plate does not form any copper layer on the second plate surface; and a pre-packaging layer, which is molded in the configuration area and covers the first copper layer so that at least a portion of the bonding surface of the first copper layer is exposed outside the pre-packaging layer; the thermal expansion coefficient of the pre-packaging layer is between the thermal expansion coefficient of the ceramic plate and the thermal expansion coefficient of the first copper layer; wherein the pre-packaging layer has a top edge and a ring side edge connected to the top edge, and the top edge is not lower than the bonding surface of the first copper layer relative to the first plate surface, and the ring side edge is flush with the ring side surface of the ceramic plate.
[0020] Optionally, the first copper layer includes: a plurality of inner copper pads, which are arranged at intervals from each other; and a plurality of outer copper pads, which are arranged at intervals around the outer sides of the plurality of inner copper pads, and the plurality of outer copper pads are arranged at intervals from each other and in a ring shape; wherein, among two edges of the plurality of inner copper pads facing each other, one edge is formed with at least one protrusion, and the other edge is formed with at least one groove, which accommodates a part of at least one protrusion.
[0021] Optionally, the first copper layer includes: a plurality of inner copper pads, which are arranged at intervals from each other; and a plurality of outer copper pads, which are arranged at intervals around the outside of the plurality of inner copper pads, and the plurality of outer copper pads are arranged at intervals from each other and in a ring shape; wherein the edges of the plurality of inner copper pads and the inner edges of the plurality of outer copper pads are both in a stepped structure and buried in the pre-packaging layer.
[0022] Optionally, at least one of the top edge and the ring side edge of the pre-packaging layer is formed with a centerline average roughness of at least 0.8 micrometers.
[0023] Optionally, a top edge of the pre-packaging layer is coplanar with a bonding surface of the first copper layer.
[0024] Optionally, the pre-packaging layer includes: a coating body formed in the configuration area and coating the first copper layer; and a bracket body extending from the coating body and protruding from the joint surface, and the bracket body has a top edge; wherein the bracket body covers a portion of the joint surface; wherein the top edge of the bracket body is separated from the joint surface by a distance of no more than 100 microns, and the bracket body and the joint surface are surrounded by a plurality of accommodating grooves.
[0025] In summary, the pre-molded direct copper-clad substrate and the manufacturing method thereof disclosed in the present application form the pre-packaging layer under specific conditions (such as: the volume of the first copper layer is less than 80% of the volume of the second copper layer; or only the first copper layer is formed), so as to effectively avoid the warping of the first copper layer (and / or the second copper layer) and reduce the stress concentration on the ceramic plate through the characteristics of the pre-packaging layer (such as: the thermal expansion coefficient of the pre-packaging layer is between the thermal expansion coefficient of the ceramic plate and the thermal expansion coefficient of the first copper layer), thereby improving the reliability and durability of the pre-molded direct copper-clad substrate.
[0026] To further understand the features and technical contents of the present application, please refer to the following detailed description and drawings of the present application. However, such description and drawings are only used to illustrate the present application and are not intended to limit the scope of protection of the present application. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] Figure 1 It is a schematic flow chart of a method for manufacturing a pre-molded direct copper clad substrate according to the first embodiment of the present application.
[0028] Figure 2 for Figure 1 A three-dimensional schematic diagram of the copper plating step and the plasma cleaning step.
[0029] Figure 3 for Figure 2 Schematic cross-sectional view along section line III-III.
[0030] Figure 4 for Figure 1 Schematic cross-sectional view of the pre-packaging step and the roughening step.
[0031] Figure 5 It is a cross-sectional schematic diagram of the pre-packaging step of the second embodiment of the present application.
[0032] Figure 6 It is a cross-sectional schematic diagram of the pre-molded direct copper clad substrate of the third embodiment of the present application.
[0033] Figure 7 It is a cross-sectional schematic diagram of another aspect of the pre-molded direct copper clad substrate of the third embodiment of the present application.
[0034] Figure 8This is a schematic top view of a pre-molded direct copper clad substrate according to the fourth embodiment of the present application.
[0035] Fig. 9 It is a top view schematic diagram of another aspect of the pre-molded direct copper clad substrate of the fourth embodiment of the present application.
[0036] Fig.10 This is a schematic top view of another embodiment of the pre-molded direct copper clad substrate of the fourth embodiment of the present application.
[0037] Fig.11 for Fig.10 Schematic cross-sectional view along section line XI-XI. DETAILED DESCRIPTION
[0038] The following is an explanation of the implementation methods of the "pre-molded direct copper-clad substrate and its manufacturing method" disclosed in the present invention through specific embodiments. Those skilled in the art can understand the advantages and effects of the present invention from the contents disclosed in this specification. The present invention can be implemented or applied through other different specific embodiments, and the details in this specification can also be modified and changed in various ways based on different viewpoints and applications without departing from the concept of the present invention. In addition, the drawings of the present invention are only simple schematic illustrations and are not depicted according to actual dimensions. It is stated in advance. The following implementation methods will further explain the relevant technical contents of the present invention in detail, but the disclosed contents are not intended to limit the scope of protection of the present invention.
[0039] It should be understood that, although the terms "first", "second", "third", etc. may be used herein to describe various components or signals, these components or signals should not be limited by these terms. These terms are mainly used to distinguish one component from another component, or one signal from another signal. In addition, the term "or" used herein may include any one or more combinations of the associated listed items depending on the actual situation.
[0040] Example 1 Please refer to Figures 1 to 4 As shown, it is the first embodiment of the present application. Figure 1 As shown, this embodiment discloses a method S100 for manufacturing a pre-molded direct copper-clad substrate, which sequentially includes (or implements) a pre-step S110, a copper-clad step S120, a plasma cleaning step S130, a pre-packaging step S140 and a roughening step S150.
[0041] The present embodiment introduces the multiple steps S110-S150 of the manufacturing method S100 of the pre-molded direct copper clad substrate in order below, but the present application is not limited thereto. For example, in other embodiments not shown in the present application, the multiple steps S110-S150 of the manufacturing method S100 of the pre-molded direct copper clad substrate can be increased, decreased or adjusted according to design requirements (e.g., the roughening step S150 can be omitted according to design requirements).
[0042] The preceding step S110: Figures 1 to 3 As shown, a ceramic plate 3 is provided, which includes a first plate surface 31, a second plate surface 32 located on the opposite side of the first plate surface 31, and a ring side surface 33 connected to the first plate surface 31 and the second plate surface 32. In this embodiment, the first plate surface 31 and the second plate surface 32 are parallel to each other, and the ring side surface 33 is vertically connected to the edge of the first plate surface 31 and the edge of the second plate surface 32. Furthermore, the specific ceramic material type used in the ceramic plate 3 can be adjusted and changed according to design requirements, and this application is not limited here.
[0043] The copper coating step S120: Figures 1 to 3 As shown, a first copper layer 1 and a second copper layer 2 eutectic-bonded thereto are formed on the first board surface 31 and the second board surface 32 of the ceramic board 3, respectively. The first copper layer 1 includes a bonding surface 11 away from the first board surface 31, and a portion of the first board surface 31 that does not contact the first copper layer 1 is defined as a configuration area 311, and the volume of the first copper layer 1 is less than 80% of the volume of the second copper layer 2, but is not limited thereto.
[0044] It should be noted that the specific implementation of the eutectic bonding of the first copper layer 1 and the second copper layer 2 to the ceramic plate 3 is not described in detail here, and the shapes of the first copper layer 1 and the second copper layer 2 can be adjusted and changed according to design requirements, and are not limited here. However, it should be noted that any step between the ceramic plate and the copper layer other than the eutectic bonding is different from the copper coating step S120 referred to in this embodiment.
[0045] The plasma cleaning step S130: Figures 1 to 3 As shown, the ceramic plate 3, the first copper layer 1 and the second copper layer 2 are cleaned. In this embodiment, the plasma cleaning step S130 is performed by plasma cleaning, but the present application is not limited thereto.
[0046] The pre-packaging step S140: Figure 1 and Figure 4As shown, a pre-packaging layer 4 is molded in the configuration area 311, so that the pre-packaging layer 4 covers the first copper layer 1, thereby forming a pre-molded direct copper clad substrate 100. Wherein, at least a part of the bonding surface 11 is exposed outside the pre-packaging layer 4, and the coefficient of thermal expansion (CTE) of the pre-packaging layer 4 is between the coefficient of thermal expansion of the ceramic plate 3 and the coefficient of thermal expansion of the first copper layer 1.
[0047] In more detail, in the pre-packaging step S140 of this embodiment, the pre-packaging layer 4 has a top edge 41 and a ring side edge 42 connected to the top edge 41, and the top edge 41 is not lower than the bonding surface 11 of the first copper layer 1 relative to the first board surface 31 (such as: the top edge 41 of the pre-packaging layer 4 is coplanar with the bonding surface 11 of the first copper layer 1), and the ring side edge 42 is flush with (or coplanar with) the ring side surface 33 of the ceramic plate 3.
[0048] The roughening step S150: Figure 1 and Figure 4 As shown, a centerline average roughness (Ra) of at least 0.8 micrometers (μm) is formed on at least one of the top edge 41 and the ring side edge 42 of the pre-packaging layer 4, so as to effectively improve the bonding between the pre-packaging layer 4 and the packaging body (not shown in the figure) during the subsequent packaging process of the pre-molded direct copper clad substrate 100.
[0049] As described above, the manufacturing method S100 of the pre-molded direct copper-clad substrate disclosed in the embodiment of the present application forms the pre-packaging layer 4 through the pre-packaging step S140 under specific conditions (such as: the volume of the first copper layer 1 is less than 80% of the volume of the second copper layer 2), so as to effectively avoid the warping of the first copper layer 1 or the second copper layer 2 and reduce the stress concentration on the ceramic plate 3 through the characteristics of the pre-packaging layer 4 (such as: the thermal expansion coefficient of the pre-packaging layer 4 is between the thermal expansion coefficient of the ceramic plate 3 and the thermal expansion coefficient of the first copper layer 1), thereby improving the reliability and durability of the pre-molded direct copper-clad substrate 100.
[0050] In addition, this embodiment generally describes the implementation process of the manufacturing method S100 of the pre-molded direct copper clad substrate with the above content, and then generally introduces the specific structure of the pre-molded direct copper clad substrate 100 from the perspective of structure. In this embodiment, the pre-molded direct copper clad substrate 100 is preferably manufactured by implementing the manufacturing method S100 of the pre-molded direct copper clad substrate, but the present application is not limited thereto.
[0051] like Figure 4 As shown, the pre-molded direct copper clad substrate 100 comprises a ceramic plate 3, a first copper layer 1 and a second copper layer 2 formed on opposite sides of the ceramic plate 3, and a pre-packaging layer 4 covering the smaller one of the first copper layer 1 and the second copper layer 2. The ceramic plate 3 (the outer surface) has a first plate surface 31, a second plate surface 32 located on the opposite side of the first plate surface 31 (and parallel to each other), and a ring side surface 33 connected to the first plate surface 31 and the second plate surface 32.
[0052] The first copper layer 1 is eutectic-bonded to the first board surface 31, the second copper layer 2 is eutectic-bonded to the second board surface 32, and the volume of the first copper layer 1 is less than 80% of the volume of the second copper layer 2. The first copper layer 1 has a bonding surface 11 away from the first board surface 31 (e.g.: Figure 4 The top surface of the first copper layer 1 in the substrate 30 is not in contact with the first copper layer 1 and is defined as a configuration area 311.
[0053] The thermal expansion coefficient of the pre-packaging layer 4 (e.g., 10-12) needs to be between the thermal expansion coefficient of the ceramic plate 3 (e.g., 5-8) and the thermal expansion coefficient of the first copper layer 1 (e.g., 16-17), so as to effectively reduce the damage to the ceramic plate 3 caused by the volume difference between the first copper layer 1 and the second copper layer 2. In addition, the pre-packaging layer 4 can be the same as or different from the packaging body (not shown in the figure) used in the subsequent packaging process of the pre-molded direct copper clad substrate 100.
[0054] Furthermore, in this embodiment, the pre-packaging layer 4 is molded in the configuration area 311 and covers the first copper layer 1, so that at least a portion of the bonding surface 11 of the first copper layer 1 is exposed outside the pre-packaging layer 4. In this embodiment, the entire bonding surface 11 of the first copper layer 1 is exposed outside the pre-packaging layer 4, but the remaining surface of the first copper layer 1 is buried in the pre-packaging layer 4.
[0055] Specifically, the pre-packaging layer 4 has a top edge 41 and a ring side edge 42 connected to the top edge 41, and the top edge 41 is not lower than the joint surface 11 of the first copper layer 1 relative to the first board surface 31 (e.g., the top edge 41 of the pre-packaging layer 4 is coplanar with the joint surface 11 of the first copper layer 1), and the ring side edge 42 of the pre-packaging layer 4 is flush with the ring side surface 33 of the ceramic plate 3. In other words, the pre-packaging layer 4 and the first copper layer 1 in this embodiment are complementary to each other, thereby forming a single-layer structure together.
[0056] At least one of the top edge 41 and the ring side edge 42 of the pre-packaging layer 4 is formed with a centerline average roughness of at least 0.8 microns, but the present application is not limited thereto. In this embodiment, the pre-packaging layer 4 is preferably formed with the centerline average roughness on its entire outer surface (that is, the top edge 41 and the ring side edge 42), thereby effectively improving the bonding between the pre-packaging layer 4 and the packaging body used in the subsequent packaging process.
[0057] Example 2 Please refer to Figure 5 As shown, it is the second embodiment of the present application. Since this embodiment is similar to the above-mentioned first embodiment, the similarities between the two embodiments will not be repeated, and the differences between this embodiment and the above-mentioned first embodiment are roughly described as follows:
[0058] In the pre-packaging step S240 of the present embodiment, the pre-packaging layer 4 protrudes from the bonding surface 11 and covers a portion of the bonding surface 11, so that the pre-packaging layer 4 and the bonding surface 11 surround and form a plurality of accommodating grooves G for respectively providing solder or sintered silver therein (not shown in the figure), but the present invention is not limited thereto. The top edge 41 of the pre-packaging layer 4 and the bonding surface 11 are preferably separated by a distance D of no more than 100 microns, and the distance D is preferably less than 30 microns, but the present application is not limited thereto.
[0059] From another perspective, the pre-packaged layer 4 of the pre-molded direct copper clad substrate 100 in this embodiment includes a covering body 4a, and a bracket body 4b extending from the covering body 4a and protruding from the bonding surface 11. The covering body 4a is formed in the configuration area 311 and covers the first copper layer 1; that is, the configuration of the covering body 4a is equivalent to the configuration of the pre-packaged layer 4 in the first embodiment.
[0060] The bracket body 4b has a top edge 41, and the top edge 41 of the bracket body 4b is separated from the bonding surface 11 by a distance D of no more than 100 microns, and the side edge of the coating body 4a and the side edge of the bracket body 4b together constitute the annular side edge 42 of the pre-packaging layer 4 and are flush with the annular side surface 33 of the ceramic plate 3.
[0061] Furthermore, the bracket body 4b covers a portion of the joint surface 11 (e.g., the bracket body 4b extends a distance E on the joint surface 11), so that the bracket body 4b and the joint surface 11 are surrounded by a plurality of the receiving grooves G, for solder or sintered silver to be respectively disposed therein, and the second copper layer 2 can be used to connect to a heat sink 300 (heatsink). It should be noted that, although the plurality of receiving grooves G are illustrated as having the same groove depth in the drawings of this embodiment, the present application is not limited thereto. For example, in other embodiments not illustrated in the present application, the plurality of receiving grooves G may have different groove depths; that is, the distance D between the top edge 41 of the bracket body 4b and the joint surface 11 may have a variety of values according to design requirements.
[0062] Example 3, please refer to Figure 6 and Figure 7 As shown, it is the third embodiment of the present application. Since this embodiment is similar to the above-mentioned embodiments 1 and 2, the similarities of the above-mentioned embodiments are not repeated here, and the differences between this embodiment and the above-mentioned embodiments 1 and 2 are roughly described as follows:
[0063] In the copper coating step of this embodiment, the ceramic plate 3 only has a first copper layer 1 eutectic-bonded thereto formed on the first plate surface 31 ; that is, the ceramic plate 3 does not have any copper layer formed on the second plate surface 32 .
[0064] Furthermore, the other steps of the manufacturing method of the pre-molded direct copper clad substrate in this embodiment are the same as those in the first or second embodiment, and the difference between the structure of the pre-molded direct copper clad substrate 100 and that of the first or second embodiment is that the second copper layer is omitted.
[0065] Example 4 Please refer to Figures 8 to 11 As shown, it is the fourth embodiment of the present application. Since this embodiment is similar to the above-mentioned embodiments 1 to 3, the same points of the above-mentioned embodiments are not repeated here, and the differences between this embodiment and the above-mentioned embodiments 1 to 3 are roughly described as follows:
[0066] In this embodiment, the first copper layer 1 includes a plurality of inner copper pads 1a arranged at intervals from each other, and a plurality of outer copper pads 1b arranged at intervals around the outer sides of the plurality of inner copper pads 1a, and the plurality of outer copper pads 1b are arranged at intervals from each other and arranged in a ring shape. Furthermore, the number of the plurality of inner copper pads 1a and the number of the plurality of outer copper pads 1b are illustrated as two each in the figure, but the present application is not limited thereto. Accordingly, the pre-molded direct copper clad substrate 100 can limit the forming area of the pre-packaging layer 4 by means of the plurality of outer copper pads 1b arranged in a ring shape, and the plurality of outer copper pads 1b can also be used together with the pre-packaging layer 4 to resist the generation of warpage.
[0067] Further, if Fig. 9 As shown, among the two edges of the plurality of inner copper pads 1a facing each other, one of the edges is formed with at least one protrusion 11a, and the other edge is formed with at least one groove 12a, which accommodates a part of at least one protrusion 11a. Accordingly, the pre-molded direct copper clad substrate 100 can effectively reduce the stress of the pre-package layer 4 in a specific direction through the cooperation of at least one protrusion 11a and at least one groove 12a of the plurality of inner copper pads 1a.
[0068] In addition, if Fig.10 and Fig.11 As shown, the first copper layer 1 can be half-etched so that the edges of the multiple inner copper pads 1a and the inner edges of the multiple outer copper pads 1b are all in a stepped structure 12 and buried in the pre-packaged layer 4. Accordingly, the pre-molded direct copper clad substrate 100 can further improve the bonding between the first copper layer 1 and the pre-packaged layer 4 through the stepped structure 12 of the first copper layer 1.
[0069] Technical effects of the present application In summary, the pre-molded direct copper-clad substrate and the manufacturing method thereof disclosed in the present application form the pre-packaging layer under specific conditions (such as: the volume of the first copper layer is less than 80% of the volume of the second copper layer; or only the first copper layer is formed), so as to effectively avoid warping of the first copper layer (and / or the second copper layer) and reduce stress concentration on the ceramic plate through the characteristics of the pre-packaging layer (such as: the thermal expansion coefficient of the pre-packaging layer is between the thermal expansion coefficient of the ceramic plate and the thermal expansion coefficient of the first copper layer), thereby improving the reliability and durability of the pre-molded direct copper-clad substrate.
[0070] Furthermore, the pre-molded direct copper-clad substrate and the manufacturing method thereof disclosed in the embodiments of the present application can also form a centerline average roughness of at least 0.8 microns through at least one of the top edge and the ring side edge of the pre-packaging layer, thereby effectively improving the bonding between the pre-packaging layer and the packaging body used in the subsequent packaging process.
[0071] In addition, the pre-molded direct copper-clad substrate disclosed in the embodiment of the present application can also improve the overall reliability and durability through the structural configuration of the first copper layer coated on the pre-packaging layer (such as: the multiple outer copper pads are arranged in a ring shape; the multiple inner copper pads form at least one protrusion and at least one groove that cooperate with each other; the first copper layer forms the stepped structure).
[0072] The contents disclosed above are only preferred feasible embodiments of the present application, and are not intended to limit the patent scope of the present application. Therefore, all equivalent technical changes made using the description and drawings of the present application are included in the patent scope of the present application.
Claims
1. A pre-molded direct copper clad substrate, characterized in that: The pre-molded direct copper-bonded substrate comprises: A ceramic plate having a first plate surface, a second plate surface located on the opposite side of the first plate surface, and a ring side surface connected to the first plate surface and the second plate surface; a first copper layer eutectically bonded to the first board surface; wherein the first copper layer has a bonding surface away from the first board surface, and a portion of the first board surface that does not contact the first copper layer is defined as a configuration area; a second copper layer eutectically bonded to the second board surface; wherein the volume of the first copper layer is less than 80% of the volume of the second copper layer; and a pre-packaging layer, which is molded and formed in the configuration area and covers the first copper layer, so that at least a part of the bonding surface of the first copper layer is exposed outside the pre-packaging layer; wherein the thermal expansion coefficient of the pre-packaging layer is between the thermal expansion coefficient of the ceramic plate and the thermal expansion coefficient of the first copper layer; The pre-packaging layer has a top edge and a ring side edge connected to the top edge, and the top edge is not lower than the bonding surface of the first copper layer relative to the first board surface, and the ring side edge is flush with the ring side surface of the ceramic plate.
2. The pre-molded direct copper clad substrate according to claim 1, characterized in that: The first copper layer comprises: A plurality of inner copper pads are arranged spaced apart from each other; and A plurality of outer copper pads are spaced around the outer sides of the plurality of inner copper pads, and the plurality of outer copper pads are spaced from each other and arranged in a ring shape.
3. The pre-molded direct copper clad substrate according to claim 2, characterized in that: Among two edges of the plurality of inner copper pads facing each other, one of the edges is formed with at least one protrusion, and the other of the edges is formed with at least one groove for accommodating a part of at least one protrusion.
4. The pre-molded direct copper clad substrate according to claim 2, characterized in that: The edges of the inner copper pads and the inner edges of the outer copper pads are all in a stepped structure and are buried in the pre-packaging layer.
5. The pre-molded direct copper clad substrate according to claim 1, characterized in that: At least one of the top edge and the ring side edge of the pre-packaging layer is formed with a centerline average roughness of at least 0.8 micrometers.
6. The pre-molded direct copper clad substrate according to claim 1, characterized in that: The top edge of the pre-encapsulation layer is coplanar with the bonding surface of the first copper layer.
7. The pre-molded direct copper clad substrate according to claim 1, characterized in that: The pre-packaging layer comprises: a coating body formed in the configuration area and coating the first copper layer; and A bracket body extends from the covering body and protrudes from the joint surface, and the bracket body has the top edge; wherein the bracket body covers a part of the joint surface.
8. The pre-molded direct copper clad substrate according to claim 7, characterized in that: The top edge of the bracket body is spaced from the joint surface by a distance of no more than 100 micrometers, and the bracket body and the joint surface surround a plurality of accommodating grooves; wherein the second copper layer is used to be connected to a heat sink.
9. A method for manufacturing a pre-molded direct copper clad substrate, characterized in that: The method for manufacturing the pre-molded direct copper clad substrate comprises: A pre-step: providing a ceramic plate having a first plate surface, a second plate surface located on the opposite side of the first plate surface, and a ring side surface connected to the first plate surface and the second plate surface; A copper coating step: forming a first copper layer eutectically bonded to the first board surface of the ceramic board; wherein the first copper layer has a bonding surface away from the first board surface, and a portion of the first board surface that does not contact the first copper layer is defined as a configuration area; a plasma cleaning step: cleaning the ceramic plate and the first copper layer; and A pre-packaging step: molding a pre-packaging layer in the configuration area so that the pre-packaging layer covers the first copper layer and at least a portion of the bonding surface is exposed outside the pre-packaging layer; wherein the thermal expansion coefficient of the pre-packaging layer is between the thermal expansion coefficient of the ceramic plate and the thermal expansion coefficient of the first copper layer.
10. The method for manufacturing a pre-molded direct copper clad substrate according to claim 9, characterized in that: In the copper coating step, a second copper layer eutectically bonded to the second surface of the ceramic plate is further formed on the second surface of the ceramic plate, and the volume of the first copper layer is less than 80% of the volume of the second copper layer.
11. The method for manufacturing a pre-molded direct copper clad substrate according to claim 9, characterized in that: After the pre-packaging step, the method for manufacturing the pre-molded direct copper clad substrate further comprises a roughening step: forming a centerline average roughness of at least 0.8 micrometers on at least one of the top edge and the ring side edge of the pre-packaging layer.
12. The method for manufacturing a pre-molded direct copper clad substrate according to claim 9, characterized in that: In the pre-packaging step, the pre-packaging layer has a top edge and a ring side edge connected to the top edge, and the top edge is not lower than the bonding surface of the first copper layer relative to the first board surface, and the ring side edge is flush with the ring side surface of the ceramic plate.
13. The method for manufacturing a pre-molded direct copper clad substrate according to claim 12, characterized in that: In the pre-packaging step, the top edge of the pre-packaging layer is coplanar with the bonding surface of the first copper layer.
14. The method for manufacturing a pre-molded direct copper clad substrate according to claim 12, characterized in that: In the pre-packaging step, the pre-packaging layer protrudes from the bonding surface and covers a portion of the bonding surface, so that the pre-packaging layer and the bonding surface surround a plurality of accommodating grooves; wherein the top edge of the pre-packaging layer is separated from the bonding surface by a distance not greater than 100 microns.
15. A pre-molded direct copper clad substrate, characterized in that: The pre-molded direct copper-bonded substrate comprises: A ceramic plate having a first plate surface, a second plate surface located on the opposite side of the first plate surface, and a ring side surface connected to the first plate surface and the second plate surface; a first copper layer eutectically bonded to the first board surface; wherein the first copper layer has a bonding surface away from the first board surface, and a portion of the first board surface that does not contact the first copper layer is defined as a configuration area, and the ceramic plate does not form any copper layer on the second board surface; and a pre-packaging layer, which is molded and formed in the configuration area and covers the first copper layer, so that at least a part of the bonding surface of the first copper layer is exposed outside the pre-packaging layer; the thermal expansion coefficient of the pre-packaging layer is between the thermal expansion coefficient of the ceramic plate and the thermal expansion coefficient of the first copper layer; The pre-packaging layer has a top edge and a ring side edge connected to the top edge, and the top edge is not lower than the bonding surface of the first copper layer relative to the first board surface, and the ring side edge is flush with the ring side surface of the ceramic plate.
16. The pre-molded direct copper clad substrate according to claim 15, characterized in that: The first copper layer comprises: A plurality of inner copper pads are arranged spaced apart from each other; and A plurality of outer copper pads are spaced around the outer sides of the plurality of inner copper pads, and the plurality of outer copper pads are spaced apart from each other and arranged in a ring shape; Among the two edges of the plurality of inner copper pads facing each other, one of the edges is formed with at least one protrusion, and the other of the edges is formed with at least one groove which accommodates a part of at least one protrusion.
17. The pre-molded direct copper clad substrate according to claim 15, characterized in that: The first copper layer comprises: A plurality of inner copper pads are arranged spaced apart from each other; and A plurality of outer copper pads are spaced around the outer sides of the plurality of inner copper pads, and the plurality of outer copper pads are spaced apart from each other and arranged in a ring shape; Wherein, the edges of the plurality of inner copper pads and the inner edges of the plurality of outer copper pads are all in a stepped structure and are buried in the pre-packaging layer.
18. The pre-molded direct copper clad substrate according to claim 15, characterized in that: At least one of the top edge and the ring side edge of the pre-packaging layer is formed with a centerline average roughness of at least 0.8 micrometers.
19. The pre-molded direct copper clad substrate according to claim 15, characterized in that: The top edge of the pre-encapsulation layer is coplanar with the bonding surface of the first copper layer.
20. The pre-molded direct copper clad substrate according to claim 15, characterized in that: The pre-packaging layer comprises: a coating body formed in the configuration area and coating the first copper layer; and A bracket body extends from the covering body and protrudes from the joint surface, and the bracket body has the top edge; wherein the bracket body covers a portion of the joint surface; wherein the top edge of the bracket body is separated from the joint surface by a distance not greater than 100 microns, and the bracket body and the joint surface are surrounded by a plurality of accommodating grooves.