Double-sided metal substrate and manufacturing method

Abstract

The invention discloses a double-sided metal substrate and a manufacturing method thereof. The double-sided metal substrate comprises a metal layer, two insulating layers, two circuit layers and a frame body. The metal layer is arranged along the horizontal direction; the two insulating layers are connected to the upper side and the lower side of the metal layer respectively, and the insulating layers extend out of the outer periphery of the metal layer; the two circuit layers are connected to the sides, away from the metal layer, of the two insulating layers in a one-to-one correspondence mode. The frame body surrounds the outer periphery of the metal layer and is located between the two insulating layers, the upper side and the lower side of the frame body are connected with the two insulating layers in a sealed mode to form a sealed cavity, and the metal layer is located in the sealed cavity; wherein the frame body is a prepreg, or the frame body is of a multi-layer board structure, and at least one layer is a first prepreg layer.

Description

Technical Field

[0001] The invention relates to the field of circuit boards, and in particular to a double-sided metal substrate and a manufacturing method thereof. Background Art

[0002] Some existing double-sided aluminum substrates include an aluminum base, two insulating layers and two circuit layers, the two insulating layers are respectively stacked on the upper and lower sides of the aluminum base, the two circuit layers are respectively stacked on the side of the two insulating layers away from the aluminum base, and the aluminum base, the insulating layer and the circuit layer are pressed together from top to bottom. The outer peripheral surface of the aluminum base of such double-sided aluminum substrate is exposed, which is easy to react with the potion in the subsequent etching or copper plating process, resulting in the outer peripheral surface of the aluminum base being corroded and contaminating the potion. An existing improvement scheme is to set a frame body around the outer peripheral surface of the aluminum base, specifically, the insulating layer is set to exceed the outer peripheral edge of the aluminum base, the frame body is sandwiched between the two insulating layers, and the upper and lower sides of the frame body are sealed and connected with the two insulating layers to form a sealed cavity that wraps the aluminum base. However, due to the influence of processing errors, the upper and lower dimensions of such a frame body and the aluminum base may not be sufficiently adapted, resulting in insufficient yield of the double-sided aluminum substrate. Summary of the invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a double-sided metal substrate that can improve the production yield.

[0004] The invention also provides a method for manufacturing the double-sided metal substrate.

[0005] According to the double-sided metal substrate of the first aspect of the present invention, the double-sided metal substrate comprises a metal layer, two insulating layers, two circuit layers and a frame body. The metal layer is arranged in a horizontal direction; the two insulating layers are respectively connected to the upper and lower sides of the metal layer, and the insulating layers extend out of the outer periphery of the metal layer; the two circuit layers are connected to the sides of the two insulating layers facing away from the metal layer in a one-to-one correspondence; the frame body is arranged around the outer periphery of the metal layer and is located between the two insulating layers, the upper and lower sides of the frame body are sealed and connected with the two insulating layers to form a sealed cavity, and the metal layer is located in the sealed cavity; wherein the frame body is a prepreg, or the frame body is a multi-layer board structure and at least one layer is a first prepreg layer.

[0006] The double-sided metal substrate according to the embodiment of the first aspect of the present invention has at least the following beneficial effects: when the double-sided metal substrate is produced, the metal layer and the frame body, the two insulating layers, and the two circuit layers need to be pressed up and down. Since the frame body is a semi-cured sheet, or has a first semi-cured sheet layer, the resin in the semi-cured sheet will be squeezed out when the frame body is pressed to reduce the thickness, so that the upper and lower dimensions of the frame body are automatically deformed to match the upper and lower dimensions of the metal layer. At this time, the two insulating layers can be in close contact with the upper and lower surfaces of the metal layer, thereby reducing the risk of insufficient yield of the double-sided metal substrate caused by loosening of the metal layer.

[0007] According to some embodiments of the present invention, the frame body includes the first prepreg layer and two hard layers, and the two hard layers are respectively connected to the upper and lower sides of the first prepreg layer.

[0008] According to some embodiments of the present invention, the first prepreg layer is fixed to the two hard layers by riveting.

[0009] According to some embodiments of the present invention, the insulating layer is a second prepreg layer, and the insulating layer is bonded to the frame body.

[0010] According to some embodiments of the present invention, a filling gap is provided between the frame body and the outer peripheral surface of the metal layer, and the filling gap is filled with resin.

[0011] According to some embodiments of the present invention, the width of the filling gap is A, satisfying 5mil≤A≤7mil.

[0012] According to some embodiments of the present invention, the outer peripheral surface of the metal layer is uneven.

[0013] According to some embodiments of the present invention, a groove is provided on the outer peripheral surface of the metal layer, the groove extends in a horizontal direction, and a notch of the groove is connected to the filling gap.

[0014] According to some embodiments of the present invention, the groove is arranged around the outer peripheral surface of the metal layer, and the groove is frame-shaped.

[0015] According to the second aspect of the present invention, the manufacturing method of the double-sided metal substrate comprises the following steps: drilling holes in the metal layer and plugging the holes with resin, and then grinding the plugged holes to make them smooth; machining an inner hole in the middle of a frame raw material plate to form the frame body, wherein the thickness of the frame raw material plate is not less than the thickness of the metal layer; embedding the metal layer into the frame body, and stacking the insulating layer on both sides of the metal layer and the frame body, and stacking the circuit layer on the side of the two insulating layers away from the metal layer, and then laminating the metal layer, the frame body, the insulating layer and the circuit layer to form a double-sided metal substrate.

[0016] The method for manufacturing a double-sided metal substrate according to the second embodiment of the present invention has at least the following beneficial effects: the double-sided metal substrate is manufactured by the above-mentioned manufacturing method with a relatively simple process and a high yield rate.

[0017] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0019] Figure 1 is a three-dimensional schematic diagram of a double-sided metal substrate according to an embodiment of the present invention;

[0020] Figure 2 is a cross-sectional schematic diagram of a double-sided metal substrate according to an embodiment of the present invention;

[0021] Figure 3 is a schematic cross-sectional view of a metal layer according to a first embodiment of the present invention;

[0022] Figure 4 is a schematic cross-sectional view of another metal layer according to the first embodiment of the present invention;

[0023] Figure 5 is a three-dimensional schematic diagram of a metal layer according to a second embodiment of the present invention;

[0024] Figure 6 The figure is a schematic flow chart of a method for manufacturing a double-sided metal substrate according to an embodiment of the present invention.

[0025] Reference numerals:

[0026] Metal layer 100, groove 110;

[0027] Insulation layer 200;

[0028] Circuit layer 300;

[0029] Frame body 400, first prepreg layer 410, hard layer 420;

[0030] The gap 500 is filled. DETAILED DESCRIPTION

[0031] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0032] In the description of the present invention, it should be understood that descriptions involving orientation, such as orientation or positional relationship indicated as up, down, etc., are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0033] In the description of the present invention, "a plurality" means more than two. If there is a description of "first" or "second", it is only used for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0034] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0035] Reference Figures 1 to 5 , is a double-sided metal substrate of an embodiment of the present invention, comprising a metal layer 100, two insulating layers 200, two circuit layers 300 and a frame body 400. The metal layer 100 is arranged in a horizontal direction; the two insulating layers 200 are respectively connected to the upper and lower sides of the metal layer 100, and the insulating layers 200 extend out of the outer periphery of the metal layer 100; the two circuit layers 300 are connected to the sides of the two insulating layers 200 away from the metal layer 100 in a one-to-one correspondence; the frame body 400 is arranged around the outer periphery of the metal layer 100 and is located between the two insulating layers 200, and the upper and lower sides of the frame body 400 are sealed and connected with the two insulating layers 200 to form a sealed cavity, and the metal layer 100 is located in the sealed cavity; wherein the frame body 400 is a prepreg, or the frame body 400 is a multi-layer board structure and at least one layer is a first prepreg layer 410.

[0036] When producing a double-sided metal substrate, it is necessary to press the metal layer 100 and the frame body 400, the two insulating layers 200, and the two circuit layers 300 up and down. Since the frame body 400 is a semi-cured sheet, or has a first semi-cured sheet layer 410, the frame body 400 will squeeze out the resin in the semi-cured sheet when it is pressed to reduce the thickness, so that the upper and lower dimensions of the frame body 400 are automatically deformed to match the upper and lower dimensions of the metal layer 100. At this time, the two insulating layers 200 can be in close contact with the upper and lower surfaces of the metal layer 100, thereby reducing the risk of insufficient yield of the double-sided metal substrate due to loosening of the metal layer 100.

[0037] In the present embodiment, the frame body 400 comprises a first prepreg layer 410 and two hard layers 420, and the two hard layers 420 are respectively connected to the upper and lower sides of the first prepreg layer 410. When the frame body 400 is produced, it is necessary to mill an inner hole on the frame raw material plate by machining to form the frame body 400. In order to avoid the frame body 400 being too soft and difficult to machine, the two hard layers 420 are stacked on the upper and lower sides of the first prepreg layer 410, and the two hard layers 420 clamp and fix the first prepreg layer 410 to form the frame raw material plate. The existence of the hard layer 420 facilitates the clamping of the limit frame raw material plate during machining to form the frame body 400 by machining. The process of cutting the frame raw material plate into the frame body 400 is not easy to slip, which facilitates the processing of the frame body 400 by the cutting tool, and is convenient for production. At this time, the frame body 400 is a three-layer plate structure.

[0038] It is conceivable that in other embodiments, the frame body 400 may be entirely made of prepreg, that is, the frame body 400 is made by cutting the prepreg, and those skilled in the art may configure the frame body 400 according to actual needs.

[0039] It is conceivable that in other embodiments, the frame body 400 can also be a four-layer, five-layer or more-layer structure, for example, having three or more hard layers 420, with a first semi-cured sheet layer 410 sandwiched between two adjacent hard layers 420, etc.

[0040] In the embodiment, the first prepreg layer 410 is fixed by riveting to the two hard layers 420. The first prepreg layer 410 is fixed by riveting to the two hard layers 420, so that the stacked structure of the entire frame body 400 is relatively stable, and it is convenient for the frame body 400 to be made by cutting, and it is convenient for the frame body 400 to maintain the stacked structure of the entire frame body 400 when the frame body 400 and the insulating layer 200 are pressed together, so that the two hard layers 420 and the first prepreg layer 410 are not easy to slip.

[0041] In the embodiment, the insulating layer 200 is a second prepreg layer, and the insulating layer 200 is bonded to the frame body 400. The insulating layer 200 is made of a prepreg material as a whole. When the metal layer 100 and the frame body 400, the two insulating layers 200, and the two circuit layers 300 are pressed together, the insulating layer 200 can squeeze out a certain amount of resin, and the frame body 400 is directly bonded to the insulating layer 200 to achieve a sealed connection between the two, so that there is no need to bond the insulating layer 200 and the frame body 400 with additional glue for sealing connection. The processing and production is relatively convenient, and the processability is better. In addition, the insulating layer 200 can also be bonded to the metal layer 100 to improve the overall stability and structural strength of the double-sided metal substrate.

[0042] In the embodiment, there is a filling gap 500 between the frame body 400 and the peripheral surface of the metal layer 100, and the filling gap 500 is filled with resin. Since the metal layer 100 needs to be embedded in the frame body 400, in order to facilitate the embedding process of the metal layer 100 and the frame body 400, the inner hole of the frame body 400 is slightly larger than the size of the metal layer 100, and the metal layer 100 can be relatively smoothly loaded into the inner hole of the frame body 400, and the assembly is relatively convenient. When the metal layer 100 and the frame body 400, the two insulating layers 200, and the two circuit layers 300 are pressed up and down, the frame body 400 has a first prepreg layer 410, and the resin extruded from the first prepreg layer 410 can be directly filled into the filling gap 500, so that the metal layer 100 and the frame body 400 are tightly bonded, which can prevent the metal layer 100 from being loosened in the horizontal direction, and can also reduce the degree of overflow of the outer peripheral side of the frame body 400, and the production processability of the double-sided metal substrate is good.

[0043] Specifically, the material of the hard layer 420 of the frame body 400 may be a cured resin, such as an acrylic sheet, or other insulating solid non-metallic sheets.

[0044] In the embodiment, the width of the filling gap 500 is A, which satisfies 5mil≤A≤7mil. If the filling gap 500 is too large, although it is easier for the metal layer 100 to be embedded in the frame body 400, the amount of resin extruded from the first semi-cured sheet layer 410 of the frame body 400 may not be able to fill the filling gap 500, resulting in holes inside the double-sided metal substrate, affecting the quality; if the filling gap 500 is too small, it is difficult for the metal layer 100 to be embedded in the frame body 400. Therefore, after experiments, the above-mentioned filling gap 500 size is selected, and the metal layer 100 is relatively easy to be embedded in the frame body 400, and the filling gap 500 is relatively easy to be filled with resin. Specifically, the width of the filling gap 500 refers to the distance between the outer peripheral surface of the metal layer 100 and the frame body 400.

[0045] In the embodiment, the outer circumference of the metal layer 100 is uneven, which is conducive to the bonding between the outer circumference of the metal layer 100 and the filled resin, so that the metal layer 100 and the frame body 400 are relatively firmly bonded through the resin, thereby improving the structural strength of the metal part.

[0046] In the first embodiment, the outer peripheral surface of the metal layer 100 is provided with a groove 110, and the groove 110 extends in the horizontal direction, and the notch of the groove 110 is communicated with the filling gap 500. When pressing up and down, the resin extruded from the first prepreg layer 410 of the frame body 400 is filled into the filling gap 500. Since the notch of the groove 110 is communicated with the filling gap 500, the resin can also be synchronously flowed and filled into the groove 110, thereby increasing the bonding area between the metal layer 100 and the resin. And since the groove 110 is also filled with resin, when the frame body 400 is subjected to external forces in the up and down directions relative to the metal layer 100, the frame body 400 is not easy to separate and crack from the metal layer 100 up and down, and the frame body 400 is not easy to break, even if the frame body 400 is partially broken during use, it is not easy to fall off the metal layer 100, so as to avoid the fragments from affecting the inside of the device.

[0047] In the first embodiment, the cross section of the groove 110 is rectangular. When the upper and lower thicknesses B of the metal layer 100 satisfy 0.83mm≤B≤1.5mm, a groove 110 is provided in the middle of the outer peripheral surface of the metal layer 100 in the upper and lower directions, the width C of the groove 110 is 0.25mm, and the depth D of the groove 110 is 0.1mm; when the upper and lower thicknesses B of the metal layer 100 satisfy 1.5mm<B≤2.0mm, at this time, the outer peripheral surface of the metal layer 100 is provided with two grooves 110 arranged at intervals in the upper and lower directions, the distance E between the upper groove 110 and the upper surface of the metal layer 100 is 0.4mm, and the distance F between the lower groove 110 and the lower surface of the metal layer 100 is 0.4mm. When the upper and lower thicknesses B of the metal layer 100 satisfy B<0.83mm, the groove 110 is not provided.

[0048] In the second embodiment, the outer peripheral surface of the metal layer 100 is provided with a groove 110, the extension direction of the groove 110 is inclined relative to the horizontal direction, and the notch of the groove 110 is connected to the filling gap 500. The extension direction of the groove 110 is inclined relative to the horizontal direction, so that when the frame body 400 is subjected to various external forces relative to the metal layer 100, the frame body 400 is not easy to separate and crack from the metal layer 100, thereby improving the structural stability of the metal layer 100 connected to the frame body 400 through the resin.

[0049] In the embodiment, the groove 110 is disposed around the outer peripheral surface of the metal layer 100 , and the groove 110 is frame-shaped, so that the entire outer peripheral surface of the metal layer 100 can be better bonded and fixed to the frame body 400 through the resin.

[0050] Furthermore, in some embodiments, the cross section of the groove 110 is trapezoidal, and the notch width of the groove 110 is smaller than the groove bottom width of the groove 110. That is, the groove 110 is a dovetail groove, and when the resin is filled into the groove 110 and solidified, the shape of the groove 110 can fix the resin in all directions, so that the metal layer 100 and the frame body 400 are more secure, and even if the frame body 400 is cracked, the trapezoidal groove 110 can limit the cracked part through the resin, reducing the risk of the frame body 400 fragments falling.

[0051] Specifically, the metal layer 100 is usually an aluminum-based layer. It is conceivable that in other embodiments, the metal layer 100 may also be made of other materials, and those skilled in the art may configure the metal layer 100 according to actual needs.

[0052] Reference Figure 6 The present invention also discloses a manufacturing method for manufacturing the above-mentioned double-sided metal substrate, comprising the following steps:

[0053] S10: drilling holes on the metal layer 100 and plugging the holes with resin, and then polishing the plugged holes to make them smooth;

[0054] S20: machining an inner hole in the middle of the frame raw material plate to form a frame body 400, wherein the thickness of the frame raw material plate is not less than the thickness of the metal layer 100;

[0055] S30: embed the metal layer 100 into the frame body 400, and stack the insulating layer 200 on both sides of the metal layer 100 and the frame body 400, and stack the circuit layer 300 on the side of the two insulating layers 200 away from the metal layer 100, and then press the metal layer 100, the frame body 400, the insulating layer 200 and the circuit layer 300 to form a double-sided metal layer 100.

[0056] The double-sided metal substrate is manufactured by the above manufacturing method, and the process is relatively simple and the yield rate is high.

[0057] Furthermore, after step S30, the following steps are also included:

[0058] S40: cutting the outer periphery of the double-sided metal substrate so that the distance G between the outer periphery of the frame body 400 and the outer periphery of the metal layer 100 after cutting is greater than 15 mm.

[0059] By cutting the periphery of the double-sided metal substrate, the uneven portion caused by the glue flow of the frame body 400 can be removed, and the size and shape of the double-sided metal substrate can be made to meet the standard usage requirements.

[0060] Furthermore, in step S10 , it also includes: cutting a groove 110 on the outer peripheral surface of the metal layer 100 .

[0061] Furthermore, in step S20, before machining an inner hole in the middle of the frame raw material plate, it also includes: browning the hard layer 420, stacking the hard layer 420, the first semi-cured sheet layer 410 and the hard layer 420 in sequence, and fusing the contact surface between the hard layer 420 and the first semi-cured sheet layer 410, and then using rivets to rivet the two hard layers 420 and the two first semi-cured sheet layers 410 to make the frame raw material plate.

[0062] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0063] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A double-sided metal substrate, characterized in that: include: The metal layer (100) is arranged in a horizontal direction; Two insulating layers (200) are respectively connected to the upper and lower sides of the metal layer (100), and the insulating layers (200) extend beyond the outer periphery of the metal layer (100); Two circuit layers (300) are connected to the sides of the two insulating layers (200) facing away from the metal layer (100) in a one-to-one correspondence; A frame body (400) is arranged around the outer periphery of the metal layer (100) and is located between the two insulating layers (200); the upper and lower sides of the frame body (400) are sealed and connected to the two insulating layers (200) to form a sealed cavity; the metal layer (100) is located in the sealed cavity; Wherein, the frame body (400) is a prepreg, or the frame body (400) is a multi-layer board structure and at least one layer is a first prepreg layer (410).

2. The double-sided metal substrate according to claim 1, characterized in that: The frame body (400) comprises the first prepreg layer (410) and two hard layers (420), and the two hard layers (420) are respectively connected to the upper and lower sides of the first prepreg layer (410).

3. The double-sided metal substrate according to claim 2, characterized in that: The first prepreg layer (410) is fixed to the two hard layers (420) by riveting.

4. The double-sided metal substrate according to claim 1, characterized in that: The insulating layer (200) is a second prepreg layer, and the insulating layer (200) is bonded to the frame body (400).

5. The double-sided metal substrate according to claim 1, characterized in that: A filling gap (500) is provided between the frame body (400) and the outer peripheral surface of the metal layer (100), and the filling gap (500) is filled with resin.

6. The double-sided metal substrate according to claim 5, characterized in that: The width of the filling gap (500) is A, satisfying 5mil≤A≤7mil.

7. The double-sided metal substrate according to claim 5, characterized in that: The outer peripheral surface of the metal layer (100) is uneven.

8. The double-sided metal substrate according to claim 5, characterized in that: The outer peripheral surface of the metal layer (100) is provided with a groove (110), the groove (110) extends in a horizontal direction, and the notch of the groove (110) is connected to the filling gap (500).

9. The double-sided metal substrate according to claim 8, characterized in that: The groove (110) is arranged around the outer peripheral surface of the metal layer (100), and the groove (110) is frame-shaped.

10. A method for manufacturing a double-sided metal substrate, wherein the double-sided metal substrate is the double-sided metal substrate according to any one of claims 1 to 9, characterized in that: The following steps are involved: Drilling holes in the metal layer (100) and plugging the holes with resin, and then grinding the plugged holes to make them smooth; An inner hole is machined in the middle of a frame raw material plate to form the frame body (400), wherein the thickness of the frame raw material plate is not less than the thickness of the metal layer (100); The metal layer (100) is embedded in the frame body (400), and the insulating layer (200) is stacked on both sides of the metal layer (100) and the frame body (400), and the circuit layer (300) is stacked on the side of the two insulating layers (200) facing away from the metal layer (100), and then the metal layer (100), the frame body (400), the insulating layer (200) and the circuit layer (300) are pressed together to form a double-sided metal substrate.

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