Etching compensation structure and method for warping of thick copper ceramic copper-clad carrier plate

Abstract

The invention discloses an etching compensation structure and method for warping of a thick copper ceramic copper-clad carrier plate, relates to the technical field of ceramic copper-clad carrier plates, and can solve the warping problem of the thick copper ceramic copper-clad carrier plate. The etching compensation method for warping of the thick copper ceramic copper-clad carrier plate comprises a copper-clad carrier plate main body which is warped due to inconsistent material quantities of a double-sided copper plate, and comprises the following steps: S1, covering a convex side surface of the warped copper-clad carrier plate main body with an anti-corrosion blue film; s2, punching film holes, namely punching at least one etching hole array region for etching and compensating warping on the anti-corrosion blue film corresponding to the warping region of the copper-clad carrier plate main body; a plurality of film holes are distributed in a single etching hole array area; and S3, chemical etching: carrying out chemical etching on the warping region of the copper-clad carrier plate main body by etching the hole array region to form an etching compensation structure capable of reducing the material quantity of the copper plate in the warping region of the copper-clad carrier plate main body.

Description

Technical Field

[0001] The invention relates to the technical field of ceramic copper-clad carrier boards, and in particular to an etching compensation structure and method for warping of thick copper ceramic copper-clad carrier boards. Background Art

[0002] Ceramic copper-clad substrate is an important electronic packaging material, widely used in power electronics and high-power electronic modules. Its substrate is a ceramic board, which is a composite material formed by covering thick copper plates on both sides of a ceramic substrate through a specific process.

[0003] At present, thick copper-clad ceramic substrates with double-sided copper plates will have arched warping. In the case of excessive warping of the ceramic substrate, such as positive warping and warping exceeding 1.2mm, the marking adsorption platform cannot be fully adsorbed. Due to the warping, the focal length is inconsistent during marking, resulting in poor color difference after marking.

[0004] Based on the above background, the inventors have designed an etching compensation structure and method for the warping of thick copper ceramic copper-clad carrier boards to solve the warping problem of thick copper ceramic copper-clad carrier boards, and thus proposed the present application. Summary of the invention

[0005] The purpose of the present application is to provide an etching compensation structure and method for the warping of thick copper ceramic copper-clad carrier boards, so as to solve the warping problem of thick copper ceramic copper-clad carrier boards.

[0006] In order to solve the above technical problems, the present invention adopts the following solutions: On the one hand, the present application provides an etching compensation method for warping of a thick copper ceramic copper-clad carrier board, including a copper-clad carrier board body warped due to inconsistent material amounts of double-sided copper boards, specifically comprising the following steps: S1. Covering the convex side surface of the warped copper-clad substrate body with an anti-corrosion blue film; S2, punching film holes, punching at least one etching hole array area for etching compensation for warping at the anti-corrosion blue film position corresponding to the warping area of ​​the copper-clad substrate body; Multiple membrane holes are distributed in a single etched hole array area; S3, chemical etching, chemically etching the warped area of ​​the copper-clad substrate body through the etching hole array area to form an etching compensation structure that can reduce the amount of copper plate material in the warped area of ​​the copper-clad substrate body.

[0007] In step S3, during the chemical etching process, it is also necessary to observe the degree of recovery and flattening of the warped area of ​​the copper-clad carrier body. When the depth of the etching compensation structure reaches half the thickness of the copper plate or the etching of the warped area of ​​the copper-clad carrier body is restored and flattened, the chemical etching is stopped.

[0008] Optionally, when the warping area is located in the middle area of ​​the copper-clad substrate body and the copper-clad substrate body is warped in an arch shape as a whole, the etching hole array area is located in the middle area of ​​the anti-corrosion blue film corresponding to the position of the maximum curvature; The shape of the etched hole array area is a long strip or a rectangle.

[0009] Optionally, the number of the etching hole array region is one, the shape of the etching hole array region is rectangular, and the length direction of the etching hole array region is parallel to the center line of the warping region; The distribution density of the membrane holes in the etching hole array region increases gradually in the direction close to the center line of the warping region; The corresponding etching compensation structure of the rectangular etching hole array area after chemical etching is a groove structure with a V-shaped longitudinal section.

[0010] Optionally, the number of the etching hole array regions is multiple, and the shape of the etching hole array regions is long strips, and the multiple long strips of etching hole array regions are arranged parallel to each other; The spacing between the plurality of long strip-shaped etched hole array regions decreases in a direction close to the center line of the warping region; The membrane pores are evenly distributed within a single etched hole array area; The corresponding etching compensation structure of a single long strip etched hole array region after chemical etching is a long strip groove structure.

[0011] Optionally, in the case where the warped area is located at the edge of the copper-clad carrier body, the etching hole array area is located at the edge area of ​​the warped area corresponding to the anti-corrosion blue film; The shape of the etching hole array area is any one of a rectangle, a triangle, a trapezoid, and a semicircle.

[0012] Optionally, the number of the etching hole array area is one, the shape of the etching hole array area is rectangular, and the etching hole array area is arranged at a position where the curvature of the warping area is the largest; The density of membrane pores in the etched hole array region decreases toward the direction of minimum curvature; The corresponding etching compensation structure of the rectangular etching hole array area after chemical etching is a slope groove structure with a right-angled triangle in the longitudinal section.

[0013] Optionally, the number of the etching hole array regions is multiple, and the multiple etching hole array regions are evenly distributed in the edge region of the anti-corrosion blue film; The membrane holes in the etched hole array region are evenly distributed, and the number of membrane holes in the etched hole array region decreases along the direction of the minimum curvature; The shape of the etching hole array area is any one of a triangle, a trapezoid, and a semicircle; The corresponding etching compensation structure of the etching hole array area is a groove structure with a triangular, trapezoidal or semicircular cross section.

[0014] Optionally, the shape of the etching hole array area is a triangle.

[0015] Optionally, before S1 or S2, it is also necessary to detect and determine the position of the warped area of ​​the copper-clad substrate body to determine whether the warped area is located in the middle area and / or the edge area.

[0016] On the other hand, the present application provides an etching compensation structure for warping of a thick copper ceramic copper-clad carrier board, wherein the etching compensation structure is manufactured by any of the etching compensation methods for warping of a thick copper ceramic copper-clad carrier board.

[0017] The beneficial effects of the present invention compared to the prior art are as follows: The present application forms an etching hole array area with multiple film holes distributed inside on the anti-corrosion blue film corresponding to the warping area of ​​the copper-clad carrier body, and then etches the warping area of ​​the copper-clad carrier body by chemical etching to form an etching compensation structure. The copper content in the warping area can be reduced, so that the copper material amounts of the copper plates on both sides of the ceramic substrate are almost consistent, fundamentally solving the problem of warping of thick copper ceramic copper-clad carrier boards caused by inconsistent stress due to inconsistent copper content on both sides of the ceramic substrate.

[0018] 2. The etching hole array area of ​​the present application is located in the middle or above the edge of the copper-clad substrate body, so that the etching compensation structure will not affect the area where electronic devices need to be installed later, and can avoid affecting subsequent process steps while compensating for the warping of the copper-clad substrate body as much as possible. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the process of Example 1 of the present application.

[0020] Figure 2 This is a structural schematic diagram of the case where the warping area is located in the middle area in Example 1 of the present application and the etching hole array area is rectangular.

[0021] Figure 3 This is a structural schematic diagram of the case where the warping area is located in the middle area in Example 1 of the present application and the etching hole array area is in the shape of a long strip.

[0022] Figure 4 This is a structural schematic diagram of the case where the warping area is located in the edge area and the etching hole array area is rectangular in Example 1 of the present application.

[0023] Figure 5 This is a structural schematic diagram of the case where the warping area is located in the edge area and the etching hole array area is triangular in Example 1 of the present application.

[0024] Figure 6This is a structural schematic diagram of the etching compensation structure when the warping area is located in the middle area in Example 2 of the present application and the etching hole array area is rectangular.

[0025] Figure 7 This is a structural schematic diagram of the etching compensation structure when the warping area is located in the middle area in Example 2 of the present application and the etching hole array area is in the shape of a long strip.

[0026] Figure 8 This is a structural schematic diagram of the etching compensation structure when the warping area is located in the edge area and the etching hole array area is rectangular in Example 2 of the present application.

[0027] Fig. 9 This is a structural schematic diagram of the etching compensation structure when the warping area is located in the edge area and the etching hole array area is triangular in Example 2 of the present application.

[0028] Explanation of the reference numerals: 1-anti-corrosion blue film, 11-etching hole array area, 111-membrane hole, 2-ceramic substrate, 3-front copper plate, 4-rear copper plate, 5-etching compensation structure. DETAILED DESCRIPTION

[0029] The present invention will be further described in detail below in conjunction with embodiments and drawings, but the embodiments of the present invention are not limited thereto.

[0030] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "longitudinal", "lateral", "horizontal", "inside", "outside", "front", "back", "top", "bottom" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, or are the directions or positional relationships in which the inventive product is usually placed when used. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0031] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "disposed", "opened", "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0032] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0033] Embodiment 1: like Figures 1 to 5 As shown, the present embodiment provides an etching compensation method for warping of a thick copper ceramic copper-clad substrate, including a copper-clad substrate body warped due to inconsistent material amounts of double-sided copper plates, specifically comprising the following steps: S1, covering the convex side surface of the warped copper-clad carrier body with an anti-corrosion blue film 1; S2, punching film holes 111, punching at least one etching hole array area 11 for etching compensation warping at the position of the anti-corrosion blue film 1 corresponding to the warping area of ​​the copper-clad carrier body; A plurality of membrane holes 111 are distributed in a single etching hole array region 11; S3, chemical etching, chemically etching the warped area of ​​the copper-clad substrate body through the etching hole array area 11, to form an etching compensation structure 5 that can reduce the amount of copper plate material in the warped area of ​​the copper-clad substrate body.

[0034] In step S3, during the chemical etching process, it is also necessary to observe the degree of recovery and flattening of the warped area of ​​the copper-clad carrier body. The chemical etching is stopped when the depth of the etching compensation structure 5 reaches half the thickness of the copper plate or the etching of the warped area of ​​the copper-clad carrier body is restored and flattened. The etching depth is lower than half the thickness of the copper plate, which can ensure the structural strength of the copper plate. In this embodiment, the flattening state of the copper-clad carrier body during the chemical etching process can be observed by a camera device.

[0035] After research, the inventor found that the amount of copper plate material on both sides of the ceramic substrate 2 is usually not completely consistent, resulting in inconsistent stress on both sides of the ceramic substrate 2, which in turn causes the entire ceramic copper-clad carrier board to warp. On this basis, there are usually two situations. One is that the thickness of the copper plates on both sides of the ceramic substrate 2 is consistent, but because the pattern needs to be etched on the front copper plate 3, the amount of material on the front copper plate 3 is less than that on the back side, causing the entire ceramic copper-clad carrier board to warp toward the side of the back copper plate 4. Second, when the front copper plate 3 is thicker, the entire ceramic copper-clad carrier board will directly warp toward the side of the front copper plate 3.

[0036] Therefore, in this embodiment, the above method is used to punch an etched hole array area 11 with multiple film holes 111 distributed inside on the anti-corrosion blue film 1 corresponding to the warped area of ​​the copper-clad substrate body, and then the warped area of ​​the copper-clad substrate body is etched by chemical etching to form an etching compensation structure 5, which can reduce the copper content in the warped area, so that the copper material amount of the copper plates on both sides of the ceramic substrate 2 is almost consistent, fundamentally solving the problem of warping of thick copper ceramic copper-clad substrates caused by inconsistent stress due to inconsistent copper content on both sides of the ceramic substrate 2.

[0037] In addition, the etching hole array area 11 of the present embodiment is located in the middle or above the edge of the copper-clad substrate body, so that the etching compensation structure 5 will not affect the area where electronic devices need to be installed later, and can avoid affecting the subsequent process steps while compensating for the warping of the copper-clad substrate body as much as possible.

[0038] The etching compensation structure 5 in this embodiment is actually a subtractive structure for removing copper material. The etching compensation structure 5 in this embodiment is located on the front copper plate 3 with a larger amount of copper material.

[0039] The chemical etching in this embodiment uses an acidic etching solution, which is a prior art and will not be described in detail here. By controlling the etching speed, the depth of the etching compensation structure 5 can be controlled, thereby controlling the amount of copper material removed from the copper-clad carrier body after chemical etching.

[0040] Specifically, Figure 2 and Figure 3 As shown, in this embodiment, when the warping area is located in the middle area of ​​the copper-clad substrate body and the copper-clad substrate body is warped in an arch shape as a whole, the etching hole array area 11 is located in the middle area of ​​the anti-corrosion blue film 1 corresponding to the position of the maximum curvature; The shape of the etching hole array region 11 is a long strip or a rectangle, and the length direction of the rectangular or long strip etching hole array region 11 is parallel to the center line of the warping region.

[0041] Generally speaking, the position with the maximum curvature of the warping area of ​​the copper-clad substrate body is located at its midline position. Therefore, the etching hole array area 11 is located in the middle area of ​​the anti-corrosion blue film 1 corresponding to the position with the maximum curvature. After etching, the amount of copper material of the copper-clad substrate body at the position with the maximum curvature can be reduced, thereby improving the stress uniformity of the entire copper-clad substrate body.

[0042] Specifically, in this embodiment, Figure 2 As shown, the number of the etching hole array region 11 is one, and its shape is rectangular. The length direction of the etching hole array region 11 is parallel to the center line of the warping region. The distribution density of the film holes 111 in the etching hole array region 11 increases gradually in the direction close to the center line of the warping region; The corresponding etching compensation structure 5 of the rectangular etching hole array area 11 after chemical etching is a rectangular groove structure with a V-shaped longitudinal section.

[0043] In this embodiment, the shape of the membrane hole 111 can be circular, rectangular, regular hexagonal, etc., and the membrane holes 111 in the etching hole array area 11 have the same size. Therefore, the distribution density of the membrane holes 111 in the etching hole array area 11 increases along the direction close to the center line of the warping area, so that the depth of the etching compensation structure 5 under the etching hole array area 11 increases along the direction close to the center line of the warping area, thereby improving the uniformity of the copper material amount at each position of the copper plate, and then improving the stress uniformity at each position of the copper plate.

[0044] Specifically, in this embodiment, Figure 3 As shown, there are multiple etching hole array regions 11, which are in the shape of long strips, and multiple long strip etching hole array regions 11 are arranged parallel to each other; And the spacing between the plurality of long strip-shaped etched hole array regions 11 decreases gradually in the direction close to the center line of the warping region; The membrane pores 111 in the single etched hole array region 11 are evenly distributed; The corresponding etching compensation structure 5 of a single long strip etched hole array area 11 after chemical etching is a long strip groove structure. In this embodiment, the shape and size of each long strip groove structure are the same, and the amount of copper material taken out is the same. Since the spacing between the multiple long strip etched hole array areas 11 decreases in the direction close to the center line of the warping area, the closer the position is to the center line of the warping area, the more the amount of copper material is reduced, thereby improving the uniformity of the amount of copper material at each position of the copper plate, and then improving the uniformity of stress at each position of the copper plate.

[0045] Specifically, in this embodiment, Figure 4 and Figure 5 As shown, in the case where the warping area is located at the edge of the copper-clad substrate body, the etching hole array area 11 is located at the edge area corresponding to the warping area on the anti-corrosion blue film 1; The shape of the etching hole array area 11 is any one of a rectangle, a triangle, a trapezoid, and a semicircle.

[0046] Specifically, in this embodiment, Figure 4 As shown, the number of the etching hole array area 11 is one, the shape of which is rectangular, and is arranged at the position where the curvature of the warping area is the largest; The density of the membrane holes 111 in the etched hole array region 11 decreases along the direction toward the minimum curvature; After chemical etching, the corresponding etching compensation structure 5 of the rectangular etching hole array area 11 is a slope groove structure with a right-angled triangle in longitudinal section.

[0047] In this embodiment, the density of the film holes 111 in the etching hole array area 11 decreases along the direction of the smallest curvature, which can make the copper plate amount at each position as uniform as possible and avoid affecting other areas where electronic devices need to be installed later.

[0048] Specifically, in this embodiment, the number of the etching hole array regions 11 is multiple, and the multiple etching hole array regions 11 are evenly distributed in the edge region of the anti-corrosion blue film 1; The membrane holes 111 in the etching hole array region 11 are evenly distributed, and the number of the membrane holes 111 in the etching hole array region 11 decreases along the direction toward the minimum curvature; The shape of the etching hole array area 11 is any one of a triangle, a trapezoid, and a semicircle. The number of the etching hole array areas 11 can be 3, 4, 5, 6 or other numbers, which will not be specifically mentioned here.

[0049] The corresponding etching compensation structure 5 of the etching hole array area 11 is a groove structure with a triangular, trapezoidal or semicircular cross section. In this embodiment, the shape of the etching hole array area 11 is triangular, and technicians can also set the shape of the etching hole array area 11 to be a trapezoidal, semicircular or other shapes in which the number of membrane holes 111 can decrease along the direction of the minimum curvature, and the specific examples are not repeated here.

[0050] Specifically, in this embodiment, Figure 5 As shown, the shape of the etching hole array area 11 is a triangle, and the etching compensation structure 5 corresponding to the triangular etching hole array area 11 is a groove structure with a triangular cross-section. In this embodiment, a plurality of triangular etching hole array areas 11 are symmetrically arranged to improve the uniformity of the material amount and stress uniformity at various positions of the copper-clad substrate body and reduce the warping.

[0051] Specifically, in this embodiment, before S1 or S2, it is necessary to detect and determine the position of the warped area of ​​the copper-clad substrate body to determine whether the warped area is located in the middle area or / and the edge area. Through the warping detection and judgment, the etching hole array area 11 can be punched according to the position of the warped area, thereby performing etching reduction.

[0052] Embodiment 2: like Figures 6 to 9 As shown, this embodiment provides an etching compensation structure 5 for warping of thick copper ceramic copper-clad carrier boards. The etching compensation structure 5 is manufactured by the above-mentioned etching compensation method for warping of thick copper ceramic copper-clad carrier boards.

[0053] like Figure 6 As shown, in the case where the warping area is arched, the position of maximum curvature is located in the middle of the copper-clad carrier body, the number of etching hole array areas 11 is one, and its shape is rectangular, the etching compensation structure 5 after chemical etching is a rectangular groove structure with a V-shaped longitudinal section.

[0054] like Figure 7As shown, in the case where the warping area is arched, the position of the maximum curvature is located in the middle of the copper-clad substrate body, the number of etching hole array areas 11 is multiple, and the shape of the etching hole array area 11 is a long strip. After chemical etching, the etching compensation structure 5 is in the shape of a long strip groove structure, and the density of the multiple long strip groove structures increases along the middle position close to the copper-clad substrate body.

[0055] like Figure 8 As shown, when the warping area is located at the edge area of ​​the copper-clad substrate body, the number of etching hole array areas 11 is one and its shape is rectangular, the etching compensation structure 5 after chemical etching is a slope groove structure with a right-angled triangle in longitudinal section.

[0056] like Fig. 9 As shown, when the warping area is located at the edge area of ​​the copper-clad substrate body, the number of etching hole array areas 11 is multiple and their shape is triangular, the etching compensation structure 5 after chemical etching is in the shape of a groove structure with a triangular cross-section, and the multiple triangular groove structures are evenly distributed at the edge area of ​​the copper-clad substrate body.

[0057] It is to be understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present invention, but the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. An etching compensation method for warping of thick copper ceramic copper-clad substrate, comprising a copper-clad substrate body warped by inconsistent material amounts of double-sided copper plates, characterized in that: The specific steps include: S1. Covering the convex side surface of the warped copper-clad substrate body with an anti-corrosion blue film (1); S2, punching film holes (111), punching at least one etching hole array area (11) for etching and compensating for warping at a position of the anti-corrosion blue film (1) corresponding to the warping area of ​​the copper-clad substrate body; A plurality of membrane holes (111) are distributed in a single etched hole array region (11); S3, chemical etching, chemically etching the warped area of ​​the copper-clad substrate body through the etching hole array area (11), forming an etching compensation structure (5) that can reduce the amount of copper plate material in the warped area of ​​the copper-clad substrate body.

2. The etching compensation method for warping of thick copper ceramic copper-clad substrate according to claim 1, characterized in that: When the warping area is located in the middle area of ​​the copper-clad substrate body and the copper-clad substrate body is warped in an arch shape as a whole, the etching hole array area (11) is located in the middle area of ​​the anti-corrosion blue film (1) corresponding to the position of the maximum curvature; The shape of the etching hole array area (11) is a long strip or a rectangle.

3. The etching compensation method for warping of thick copper ceramic copper-clad substrate according to claim 2, characterized in that: The number of the etching hole array region (11) is one, and its shape is rectangular, and the length direction of the etching hole array region (11) is parallel to the midline of the warping region; The distribution density of the membrane holes (111) in the etching hole array region (11) increases gradually in a direction close to the center line of the warping region; The corresponding etching compensation structure (5) passing through the rectangular etching hole array area (11) is a groove structure with a V-shaped longitudinal section.

4. The etching compensation method for warping of thick copper ceramic copper-clad substrate according to claim 2, characterized in that: The number of the etching hole array regions (11) is multiple, and the shape of the etching hole array regions (11) is long strips, and the multiple long strips of etching hole array regions (11) are arranged parallel to each other; The spacing between the plurality of long strip-shaped etched hole array regions (11) decreases in a direction approaching the middle line of the warping region; The membrane pores (111) within a single etched hole array region (11) are evenly distributed; The etching compensation structure (5) corresponding to the long strip etching hole array region (11) is a long strip groove structure.

5. The etching compensation method for warping of thick copper ceramic copper-clad substrate according to claim 1, characterized in that: When the warped area is located at the edge of the copper-clad substrate body, the etching hole array area (11) is located at the edge area corresponding to the warped area on the anti-corrosion blue film (1); The shape of the etching hole array area (11) is any one of a rectangle, a triangle, a trapezoid, and a semicircle.

6. The etching compensation method for warping of thick copper ceramic copper-clad substrate according to claim 5, characterized in that: The number of the etching hole array area (11) is one, the shape of the etching hole array area (11) is rectangular, and the etching hole array area (11) is arranged at the position where the curvature of the warping area is the largest; The density of the membrane holes (111) in the etched hole array region (11) decreases gradually along the direction with the smallest curvature; The corresponding etching compensation structure (5) passing through the rectangular etching hole array area (11) is a slope groove structure with a right-angled triangle in longitudinal section.

7. The etching compensation method for warping of thick copper ceramic copper-clad substrate according to claim 5, characterized in that: The number of the etching hole array regions (11) is multiple, and the multiple etching hole array regions (11) are evenly distributed in the edge region of the anti-corrosion blue film (1); The membrane holes (111) in the etched hole array region (11) are evenly distributed, and the number of the membrane holes (111) in the etched hole array region (11) decreases along a direction with a minimum curvature; The shape of the etching hole array region (11) is any one of a triangle, a trapezoid, and a semicircle; The corresponding etching compensation structure (5) of the etching hole array region (11) is a groove structure with a triangular, trapezoidal or semicircular cross section.

8. The etching compensation method for warping of thick copper ceramic copper-clad substrate according to claim 7, characterized in that: The shape of the etching hole array area (11) is a triangle.

9. The etching compensation method for warping of thick copper ceramic copper-clad substrate according to claim 1, characterized in that: Before S1 or S2, it is also necessary to detect and determine the position of the warping area of ​​the copper-clad substrate body to determine whether the warping area is located in the middle area and / or the edge area.

10. An etching compensation structure for warping of thick copper ceramic copper-clad substrate, characterized in that: The etching compensation structure (5) is manufactured by an etching compensation method for warping of a thick copper ceramic copper-clad substrate as described in any one of claims 1 to 9.

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