Printed circuit board and method for detecting position deviation between layers of printed circuit board

Abstract

The embodiments of the present application are related to a printed circuit board and a method for detecting interlayer position deviation of a printed circuit board. The printed circuit board provided according to an embodiment of the present application includes: a core layer, a first metal layer, a second metal layer, a third metal layer and a fourth metal layer. The first metal layer has a first graphic mark, and the second metal layer has a second graphic mark. The first and second graphic marks constitute a layer deviation detection area, and the spacing between the first graphic mark and the second graphic mark in the projection plane of the first surface along the length direction of the printed circuit board is equal to the first preset offset value minus the amount of bite of the first metal layer and the second metal layer. The first preset offset value is the first value that allows interlayer deviation to occur between the first metal layer and the second metal layer. The method for detecting interlayer position deviation of a printed circuit board provided in the embodiments of the present application can accurately and efficiently perform interlayer detection of multi-layer printed circuit boards in a simple way.

Description

Technical Field

[0001] The present application relates to the field of semiconductor technology, and in particular to a printed circuit board and a method for detecting position deviation between layers of the printed circuit board. Background Art

[0002] With the rapid development of semiconductor technology, the alignment requirements between layers of multi-layer printed circuit boards are getting higher and higher. The target icon of the traditional printed circuit board only serves as a basic function of positioning and alignment during the lamination process of the multi-layer printed circuit board, and it cannot accurately identify whether there is inter-layer offset in the multi-layer printed circuit board.

[0003] Therefore, there are still many technical problems to be solved in the industry regarding how to accurately detect the position offset between layers of printed circuit boards. Summary of the invention

[0004] One of the purposes of the present application is to provide a printed circuit board and a method for detecting interlayer position deviation of a printed circuit board, which can perform interlayer detection of a multi-layer printed circuit board more accurately and efficiently in a simple method.

[0005] One embodiment of the present application provides a printed circuit board, which includes: a core layer, a first metal layer, a second metal layer, a third metal layer and a fourth metal layer. The first metal layer is located on the first surface of the core layer, and the first metal layer has a first metal structure. The second metal layer is arranged close to the first metal layer and away from the first surface of the core layer, and the second metal layer has a second metal structure. The third metal layer is located on the second surface of the core layer, and the second surface is opposite to the first surface. The fourth metal layer is arranged close to the third metal layer and away from the second surface of the core layer. The first metal structure and the second metal structure constitute a layer deviation detection area, the center of the first metal structure and the center of the second metal structure are both on a first straight line perpendicular to the first surface, and the spacing between the first metal structure and the second metal structure in the projection plane of the first surface along the length direction of the printed circuit board is equal to the first preset offset value minus the bite amount of the first metal layer and the bite amount of the second metal layer, and the first preset offset value is a first value that allows interlayer deviation between the first metal layer and the second metal layer.

[0006] In some embodiments of the present application, the third metal layer is formed simultaneously with the first metal layer, and the fourth metal layer is formed simultaneously with the second metal layer, wherein the layer deviation detection area also includes a third metal structure and a fourth metal structure, the third metal structure is located on one of the first metal layer and the second metal layer, the fourth metal structure is located on one of the third metal layer and the fourth metal layer that are not formed corresponding to the metal layer having the third metal structure, the center of the third metal structure and the center of the fourth metal structure are both on a second straight line perpendicular to the first surface, and the spacing between the third metal structure and the fourth metal structure in the projection plane of the first surface along the length direction of the printed circuit board is equal to the first preset offset value minus the amount of corrosion of the metal layer where the third metal structure is located and the amount of corrosion of the metal layer where the fourth metal structure is located.

[0007] In some embodiments of the present application, the printed circuit board includes four layer deviation detection areas, two of which are symmetrically arranged at the upper and lower ends of the left side of the printed circuit board, and the other two are symmetrically arranged at the upper and lower ends of the right side of the printed circuit board.

[0008] Another embodiment of the present application provides a printed circuit board, which includes: a core layer, a first metal layer, a second metal layer, a third metal layer, a fourth metal layer, a fifth metal layer and a sixth metal layer. The first metal layer is located on the first surface of the core layer, and the first metal layer has a first metal structure. The second metal layer is arranged close to the first metal layer and away from the first surface of the core layer, and the second metal layer has a second metal structure. The third metal layer is arranged close to the second metal layer and away from the first metal layer, and the third metal layer has a third metal structure. The fourth metal layer is located on the second surface of the core layer, and the second surface is opposite to the first surface. The fifth metal layer is arranged close to the fourth metal layer and away from the second surface of the core layer. The sixth metal layer is arranged close to the fifth metal layer and away from the fourth metal layer. The first metal structure, the second metal structure and the third metal structure constitute a layer deviation detection area, the center of the first metal structure, the center of the second metal structure and the center of the third metal structure are all on a first straight line perpendicular to the first surface, and the spacing between the first metal structure and the second metal structure in the projection plane of the first surface along the length direction of the printed circuit board and the spacing between the second metal structure and the third metal structure in the projection plane of the first surface along the length direction of the printed circuit board are respectively equal to the first preset offset value minus the sum of the bite amount of the metal layer where the corresponding metal structure is located, and the first preset offset value is the first value that allows interlayer deviation to occur between two adjacent metal layers.

[0009] In some embodiments of the present application, the fourth metal layer is formed simultaneously with the first metal layer, the fifth metal layer is formed simultaneously with the second metal layer, and the sixth metal layer is formed simultaneously with the third metal layer, the layer deviation detection area also includes a fourth metal structure, a fifth metal structure and a sixth metal structure, the fourth metal structure is located on one of the first metal layer, the second metal layer and the third metal layer, the fifth metal structure and the sixth metal structure are respectively located on two of the fourth metal layer, the fifth metal layer and the sixth metal layer that are not formed corresponding to the metal layer having the fourth metal structure, wherein the center of the fourth metal structure, the center of the fifth metal structure and the center of the sixth metal structure are all on a second straight line perpendicular to the first surface, and the spacing between the fourth metal structure and the fifth metal structure in the projection plane of the first surface along the length direction of the printed circuit board and the spacing between the fifth metal structure and the sixth metal structure in the projection plane of the first surface along the length direction of the printed circuit board are respectively equal to the first preset offset value minus the sum of the bite amounts of the metal layers where the corresponding metal structures are located.

[0010] In some embodiments of the present application, the layer deviation detection area also includes a seventh metal structure, an eighth metal structure and a ninth metal structure, the seventh metal structure is located on one of the remaining two metal layers among the first metal layer, the second metal layer and the third metal layer, excluding the metal layer with the fourth metal structure, the eighth metal structure and the ninth metal structure are respectively located on two of the fourth metal layer, the fifth metal layer and the sixth metal layer that are not formed corresponding to the metal layer with the seventh metal structure, wherein the center of the seventh metal structure, the center of the eighth metal structure and the center of the ninth metal structure are all on a third straight line perpendicular to the first surface, and the spacing between the seventh metal structure and the eighth metal structure in the projection plane of the first surface along the length direction of the printed circuit board and the spacing between the seventh metal structure and the ninth metal structure in the projection plane of the first surface along the length direction of the printed circuit board are respectively equal to the first preset offset value minus the sum of the bite amount of the metal layer where the corresponding metal structure is located.

[0011] In some embodiments of the present application, the layer deviation detection area also includes: a tenth metal structure located on the first metal layer, an eleventh metal structure located on the second metal layer, and a twelfth metal structure located on the third metal layer, wherein the center of the tenth metal structure, the center of the eleventh metal structure and the center of the twelfth metal structure are all on a fourth straight line perpendicular to the first surface, and the spacing between the tenth metal structure and the eleventh metal structure in the projection plane of the first surface along the length direction of the printed circuit board and the spacing between the eleventh metal structure and the twelfth metal structure in the projection plane of the first surface along the length direction of the printed circuit board are respectively equal to the second preset offset value minus the sum of the bite amounts of the metal layers where the corresponding metal structures are located, and the second preset offset value is a second value that allows interlayer deviation to occur between two adjacent metal layers.

[0012] In some embodiments of the present application, the layer deviation detection area further includes a thirteenth metal structure, a fourteenth metal structure and a fifteenth metal structure, the thirteenth metal structure is located on the metal layer having the fourth metal structure, the fourteenth metal structure is located on the metal layer having the fifth metal structure, and the fifteenth metal structure is located on the metal layer having the sixth metal structure.

[0013] Among them, the center of the thirteenth metal structure, the center of the fourteenth metal structure and the center of the fifteenth metal structure are all on the fifth straight line perpendicular to the first surface, and the spacing between the thirteenth metal structure and the fourteenth metal structure in the projection plane of the first surface along the length direction of the printed circuit board and the spacing between the fourteenth metal structure and the fifteenth metal structure in the projection plane of the first surface along the length direction of the printed circuit board are respectively equal to the second preset offset value minus the sum of the corrosion amount of the metal layer where the corresponding metal structure is located.

[0014] In some embodiments of the present application, the layer deviation detection area also includes a sixteenth metal structure, a seventeenth metal structure and an eighteenth metal structure, the sixteenth metal structure is located on the metal layer having the seventh metal structure, the seventeenth metal structure is located on the metal layer having the eighth metal structure, and the eighteenth metal structure is located on the metal layer having the ninth metal structure, wherein the center of the sixteenth metal structure, the center of the seventeenth metal structure and the center of the eighteenth metal structure are all on a sixth straight line perpendicular to the first surface, and the spacing between the sixteenth metal structure and the seventeenth metal structure in the projection plane of the first surface along the length direction of the printed circuit board and the spacing between the seventeenth metal structure and the eighteenth metal structure in the projection plane of the first surface along the length direction of the printed circuit board are respectively equal to the second preset offset value minus the sum of the bite amount of the metal layer where the corresponding metal structure is located.

[0015] In some embodiments of the present application, the layer deviation detection area also includes: a nineteenth metal structure located on the first metal layer, a twentieth metal structure located on the second metal layer, and a twenty-first metal structure located on the third metal layer, wherein the center of the nineteenth metal structure, the center of the twentieth metal structure, and the center of the twenty-first metal structure are all on a seventh straight line perpendicular to the first surface, and the spacing between the nineteenth metal structure and the twentieth metal structure in the projection plane of the first surface along the length direction of the printed circuit board and the spacing between the twentieth metal structure and the twenty-first metal structure in the projection plane of the first surface along the length direction of the printed circuit board are respectively equal to the third preset offset value minus the sum of the bite amounts of the metal layers where the corresponding metal structures are located, and the third preset offset value is a third value that allows interlayer deviation to occur between two adjacent metal layers.

[0016] In some embodiments of the present application, the layer deviation detection area further includes a twenty-second metal structure, a twenty-third metal structure, and a twenty-fourth metal structure, the twenty-second metal structure is located on the metal layer having the fourth metal structure, the twenty-third metal structure is located on the metal layer having the fifth metal structure, and the twenty-fourth metal structure is located on the metal layer having the sixth metal structure.

[0017] Among them, the center of the twenty-second metal structure, the center of the twenty-third metal structure and the center of the twenty-fourth metal structure are all on the eighth straight line perpendicular to the first surface, and the spacing between the twenty-second metal structure and the twenty-third metal structure in the projection plane of the first surface along the length direction of the printed circuit board and the spacing between the twenty-third metal structure and the twenty-fourth metal structure in the projection plane of the first surface along the length direction of the printed circuit board are respectively equal to the third preset offset value minus the sum of the corrosion amount of the metal layer where the corresponding metal structure is located.

[0018] In some embodiments of the present application, the layer deviation detection area also includes a twenty-fifth metal structure, a twenty-sixth metal structure, and a twenty-seventh metal structure, the twenty-fifth metal structure is located on the metal layer having the seventh metal structure, the twenty-sixth metal structure is located on the metal layer having the eighth metal structure, and the twenty-seventh metal structure is located on the metal layer having the ninth metal structure, wherein the center of the twenty-fifth metal structure, the center of the twenty-sixth metal structure, and the center of the twenty-seventh metal structure are all on a ninth straight line perpendicular to the first surface, and the spacing between the twenty-fifth metal structure and the twenty-sixth metal structure in the projection plane of the first surface along the length direction of the printed circuit board and the spacing between the twenty-sixth metal structure and the twenty-seventh metal structure in the projection plane of the first surface along the length direction of the printed circuit board are respectively equal to the third preset offset value minus the sum of the bite amounts of the metal layers where the corresponding metal structures are located.

[0019] In some embodiments of the present application, the first preset offset value, the second preset offset value, and the third preset offset value are different.

[0020] In some embodiments of the present application, the first preset offset value may be 50 micrometers, the second preset offset value may be 65 micrometers, and the third preset offset value may be 75 micrometers.

[0021] In some embodiments of the present application, each metal structure may be in a triangle, square or ring shape, and is disposed in a board edge region of the printed circuit board.

[0022] In some embodiments of the present application, the annular mark with the smallest diameter may be a solid circle.

[0023] In some embodiments of the present application, the printed circuit board includes four layer deviation detection areas, two of which are symmetrically arranged at the upper and lower ends of the left side of the printed circuit board, and the other two are symmetrically arranged at the upper and lower ends of the right side of the printed circuit board.

[0024] In some embodiments of the present application, the metal structure is made of copper.

[0025] Another embodiment of the present application provides a method for detecting interlayer position deviation of a printed circuit board, comprising: providing a printed circuit board as described in any of the above embodiments, irradiating the printed circuit board with X-rays, and observing whether adjacent metal structures in a layer deviation detection area are tangent or intersecting.

[0026] In some embodiments of the present application, observing whether adjacent metal structures in the layer deviation detection area are tangent to or intersect with each other includes: observing whether metal structures having the same preset offset value are tangent to or intersect with each other.

[0027] The printed circuit board and the method for detecting interlayer position deviation of the printed circuit board provided by the embodiments of the present application can perform interlayer detection of a multi-layer printed circuit board more accurately and efficiently in a simple manner. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1A Schematic diagram of the longitudinal structure of a printed circuit board according to an embodiment of the present application

[0029] Figure 1B Yes Figure 1A Schematic diagram of the top view of the printed circuit board shown

[0030] Figure 1C Yes Figure 1B A top perspective view of a layer deviation detection area of ​​a printed circuit board shown in FIG.

[0031] Figure 2A is a schematic diagram of the longitudinal structure of a printed circuit board according to another embodiment of the present application

[0032] Figure 2B Yes Figure 2A Schematic diagram of the top view of the printed circuit board shown

[0033] Figure 2C Yes Figure 2B A schematic top view perspective view of a portion of a layer deviation detection area of ​​a printed circuit board shown in FIG.

[0034] Figure 2D Yes Figure 2B A top perspective view of a layer deviation detection area of ​​a printed circuit board shown in FIG. DETAILED DESCRIPTION

[0035] In order to better understand the spirit of the present invention, it is further described below in conjunction with some preferred embodiments of the present application.

[0036] The embodiments of the present application will be described in detail below. In the full text of the present application specification, the same or similar components and components with the same or similar functions are represented by similar reference numerals. The embodiments of the accompanying drawings described herein are illustrative, graphical, and are used to provide a basic understanding of the present application. The embodiments of the present application should not be construed as limiting the present application.

[0037] As used herein, the terms "about," "substantially," and "essentially" are used to describe and illustrate small variations. When used in conjunction with an event or circumstance, the terms may refer to instances where the event or circumstance occurred exactly as well as instances where the event or circumstance occurred very approximately. For example, when used in conjunction with a numerical value, the terms may refer to a range of variation less than or equal to ±10% of the numerical value, such as less than or equal to ±5%, less than or equal to ±0.5%, or less than or equal to ±0.05%. For example, two numerical values ​​may be considered "substantially" the same if the difference between the two values ​​is less than or equal to ±10% of the average of the values.

[0038] Furthermore, for ease of description, “first”, “second”, “third”, etc. may be used herein to distinguish different components in one figure or a series of figures. “First”, “second”, “third”, etc. are not intended to describe the corresponding components.

[0039] In the present application, unless otherwise specified or limited, the terms "set", "connect", "couple", "fixed" and similar terms are used broadly, and those skilled in the art can understand that the above terms can be, for example, fixed connection, detachable connection or integrated connection according to the specific circumstances; it can also be a mechanical connection or an electrical connection; it can also be a direct connection or an indirect connection through an intermediate structure; it can also be an internal communication between two components.

[0040] The existing technology uses target graphics to roughly detect whether there is a serious interlayer offset between the layers of printed circuit boards. However, since the layers of the circuit board will shrink or expand to a certain extent during the actual manufacturing process, the target graphic detection is not accurate enough, so that the results of the interlayer offset detection cannot reflect the actual layer deviation. In addition, for the interlayer offset detection of printed circuit boards with more than four layers, especially more than six layers, it is more difficult to measure directly by machine due to the large number of layers. Therefore, the industry has been seeking a simple, efficient and accurate interlayer offset detection method.

[0041] In view of the above problems, the embodiments of the present application provide a printed circuit board and a method for detecting interlayer position offset of the printed circuit board, which realizes interlayer offset detection in a more accurate manner by setting different metal structures on each metal layer of the printed circuit board and setting the size of each graphic mark in combination with the specific bite amount of the metal layer where the metal structure is located. In addition, for interlayer offset detection between printed circuit boards with a large number of layers, especially more than six layers, the embodiments of the present application provide a simpler and more efficient detection method.

[0042] Figure 1A 1 is a schematic diagram of the longitudinal structure of a printed circuit board 10 according to an embodiment of the present application. Figure 1B Yes Figure 1A The schematic diagram of the top structure of the printed circuit board 10 is shown. Figure 1C Yes Figure 1B The schematic diagram of the top perspective view of the layer deviation detection area M1 of the printed circuit board 10 is shown.

[0043] like Figure 1A , Figure 1B and Figure 1C As shown, according to Figure 1A , Figure 1B and Figure 1C The printed circuit board 10 provided in the embodiment may include: a core layer 100 , a first metal layer 101 , a second metal layer 102 , a third metal layer 103 and a fourth metal layer 104 .

[0044] The printed circuit board 10 has a length along the X direction, a height along the Y direction perpendicular to the X direction, and a width along the Z direction perpendicular to the plane where the X direction and the Y direction are located. The entire area S of the printed circuit board 10 can be composed of the board edge area S1 and the middle area S2. The structure located in the middle area S2, such as, but not limited to, the core layer 100, the first metal layer 101, the second metal layer 102, the third metal layer 103 and the fourth metal layer 104, can be included in the final product structure of the printed circuit board 10. The structure located in the board edge area S1 does not constitute the final product structure of the printed circuit board 10.

[0045] The core layer 100 can be any commonly used core layer in the art, and its thickness and material can be set according to specific needs. The core layer 100 has a first surface 100a and a second surface 100b opposite to the first surface 100a.

[0046] The first metal layer 101 may be located on the first surface 100a of the core layer 100. The material of the first metal layer 101 disposed in the middle region S2 may be any suitable metal in the art, such as, but not limited to, copper. The material of the first metal layer 101 disposed in the board edge region S1 may include any suitable non-metallic material. The thickness of the first metal layer 101 may be set according to specific needs.

[0047] The second metal layer 102 may be disposed close to the first metal layer 101 and away from the first surface 100a of the core layer 100. The material of the second metal layer 102 disposed in the middle region S2 may be any suitable metal in the art, such as, but not limited to, copper. The material of the second metal layer 102 disposed in the board edge region S1 may include any suitable non-metallic material. The thickness of the second metal layer 102 may be set according to specific needs. The thickness and material of the second metal layer 102 may be the same as or different from the first metal layer 101.

[0048] The third metal layer 103 may be located on the second surface 100b of the core layer 100. The material of the third metal layer 103 disposed in the middle region S2 may be any suitable metal in the art, such as, but not limited to, copper. The material of the third metal layer 103 disposed in the board edge region S1 may include any suitable non-metallic material. The third metal layer 103 may be formed simultaneously with the first metal layer 101.

[0049] The fourth metal layer 104 may be disposed close to the third metal layer 103 and away from the second surface 100b of the core layer 100. The material of the fourth metal layer 104 disposed in the middle region S2 may be any suitable metal in the art, such as, but not limited to, copper. The material of the fourth metal layer 104 disposed in the board edge region S1 may include any suitable non-metallic material. The fourth metal layer 104 may be formed simultaneously with the second metal layer 102 in correspondence thereto.

[0050] The first metal layer 101 may have a first metal structure 111. The first metal structure 111 may be disposed on the first metal layer 101 in the edge region S1 by any suitable method, such as, but not limited to, etching or electroplating. The first metal structure 111 may be made of copper. The first metal structure 111 may also be made of any suitable metal material. In the plane where the X direction and the Z direction are located, the first metal structure 111 may be in a circular shape. The first metal structure 111 may also be in any suitable shape, such as, but not limited to, a triangle, a square or a circle. The size of the circular first metal structure 111 disposed in the board edge region S1 of the printed circuit board 10 may be set according to specific needs.

[0051] The second metal layer 102 may have a second metal structure 113. The second metal structure 113 may be disposed on the second metal layer 102 in the edge region S1 by any suitable method, such as, but not limited to, etching or electroplating. The second metal structure 113 may be made of copper. The second metal structure 113 may also be made of any suitable metal material. In the plane where the X direction and the Z direction are located, the second metal structure 113 may be a solid circle. The second metal structure 113 may also be in any suitable shape, such as, but not limited to, a triangle, a circular ring or a square. The circular mark with the smallest diameter in the first metal structure 111 and the second metal structure 113 may be a solid circle. The size of the circular second metal structure 113 disposed in the board edge region S1 of the printed circuit board 10 may be set according to specific needs, and it may be smaller than the size of the first metal structure 111. In other embodiments of the present application, the size of the first metal structure 111 may be smaller than the size of the second metal structure 113.

[0052] The center C1 of the first metal structure 111 and the center C2 of the second metal structure 113 are both on a first straight line L1 perpendicular to the first surface 100a. The first straight line L1 is parallel to the Y direction. The first metal structure 111 and the second metal structure 113 are in the projection plane of the first surface 100a (i.e., the plane where the X direction and the Z direction are located) along the length direction of the printed circuit board 10, that is, the spacing P1 in the X direction is equal to the first preset offset value minus the bite amount of the first metal layer 101 and the bite amount of the second metal layer 102, wherein the first preset offset value is the first value that allows the interlayer offset between the first metal layer 101 and the second metal layer 102. The first value can be set according to specific needs. "Bite amount" is defined in this article as the size of the change in the plane where the X direction and the Z direction are located along the X direction after the metal layer expands or contracts. The bite amount is not a fixed value, and it has different values ​​according to the different materials and thicknesses of the metal layer. For ease of understanding, examples are given here. Assuming that the first value allowing the interlayer offset between the first metal layer 101 and the second metal layer 102 is 50 microns, and the corrosion amounts of the first metal layer 101 and the second metal layer 102 are 20 microns and 10 microns respectively, P1 is equal to the first preset offset value (50 microns) minus the sum of the corrosion amounts of the first metal layer 101 (20 microns) and the corrosion amounts of the second metal layer 102 (10 microns), that is, P1 is equal to 20 microns.

[0053] The first metal structure 111 and the second metal structure 113 may constitute a layer deviation detection area M1. After the printed circuit board 10 is formed, in order to detect the interlayer deviation between the metal layers in the printed circuit board 10, the printed circuit board 10 may be irradiated with X-rays. Whether adjacent metal structures in the layer deviation detection area M1, i.e., the first metal structure 111 and the second metal structure 113, are tangent or intersecting with each other may be observed visually or by machine. If there is tangent or intersection, it means that the interlayer deviation between the metal layers where the two metal structures that are tangent or intersecting are located exceeds the maximum value allowed.

[0054] The printed circuit board 10 may include at least one layer deviation detection area M1. To further improve the detection accuracy, the printed circuit board 10 may preferably include four layer deviation detection areas M1, wherein two layer deviation detection areas are symmetrically arranged at the upper end and the lower end of the left side of the printed circuit board 10, and the other two layer deviation detection areas are symmetrically arranged at the upper end and the lower end of the right side of the printed circuit board, such as Figure 2C shown.

[0055] The printed circuit board 10 may further include an insulating layer 120 disposed between the first metal layer 101 and the second metal layer 102, between the third metal layer 103 and the fourth metal layer 104, on the surface of the second metal layer 102, and on the surface of the fourth metal layer 104. The material of the insulating layer 120 may be an insulating material commonly used in the art, such as, but not limited to, resin. The insulating layer 120 located at the outermost layer may be provided with one or more metal pads, which may be made of any suitable metal material, such as, but not limited to, nickel or gold, to respectively achieve electrical connection with the second metal layer 102 near the uppermost side of the printed circuit board 10 and the fourth metal layer 104 near the lowermost side of the printed circuit board 10.

[0056] The printed circuit board 10 may further include a through hole 130 penetrating the core layer 100 , the first metal layer 101 , the second metal layer 102 , the third metal layer 103 , the fourth metal layer 104 and the insulating layer 120 .

[0057] The applicant has noticed that some manufacturing processes of the printed circuit board 10 may cause the metal layer to expand or contract to a certain extent. The layer deviation detection area M1 composed of the first metal structure 111 and the second metal structure 113 provided in the embodiment of the present application sets a preset offset value considering the etching amount of different metal layers, which can detect interlayer deviation with higher precision and accuracy.

[0058] In order to obtain interlayer offset detection with higher precision and accuracy, the layer deviation detection area M1 may be further provided to include a third metal structure 115 and a fourth metal structure 117. The third metal structure 115 may be located on the second metal layer 102. The fourth metal structure 117 may be located on the third metal layer 103. In other embodiments of the present application, the third metal structure 115 may be located on one of the first metal layer 101 and the second metal layer 102, and the fourth metal structure 117 may be located on one of the third metal layer 103 and the fourth metal layer 104 formed not corresponding to the metal layer having the third metal structure 115. The material range and setting method of the third metal structure 115 and the fourth metal structure 117 may be similar to those of the first metal structure 111.

[0059] The center C3 of the third metal structure 115 and the center C4 of the fourth metal structure 117 are both on the second straight line L2 perpendicular to the first surface 100a. The second straight line L2 is parallel to the Y direction and is spaced a suitable distance from the first straight line L1. The spacing P1 between the third metal structure 115 and the fourth metal structure 117 along the length direction of the printed circuit board 10 in the projection plane of the first surface 100a (i.e., the plane where the X direction and the Z direction are located), i.e., in the X direction, is equal to the first preset offset value minus the erosion amount of the metal layer where the third metal structure 115 and the erosion amount of the metal layer where the fourth metal structure 117 are located.

[0060] By further configuring the layer deviation detection area M1 to include the third metal structure 115 and the fourth metal structure 117 , the embodiment of the present application can further improve the accuracy of inter-layer detection.

[0061] Figure 2A 2 is a schematic diagram of the longitudinal structure of a printed circuit board 20 according to another embodiment of the present application. Figure 2B Yes Figure 2A FIG. 2 is a schematic diagram of a top view of the structure of a printed circuit board 20 shown in FIG. Figure 2C Yes Figure 2B The schematic diagram of a top perspective view of a portion of the layer deviation detection area N1 of the printed circuit board 20 is shown. Figure 2D Yes Figure 2B The schematic diagram of the top perspective view of the layer deviation detection area N1 of the printed circuit board is shown.

[0062] like Figure 2A , Figure 2B , Figure 2C and Figure 2D As shown, according to Figure 2A , Figure 2B , Figure 2C and Figure 2DThe printed circuit board 20 provided in the embodiment may include: a core layer 200 , a first metal layer 201 , a second metal layer 202 , a third metal layer 203 , a fourth metal layer 204 , a fifth metal layer 205 and a sixth metal layer 206 .

[0063] The printed circuit board 20 has a length along the X direction, a height along the Y direction perpendicular to the X direction, and a width along the Z direction perpendicular to the plane where the X direction and the Y direction are located. The entire area S' of the printed circuit board 20 can be composed of the board edge area S3 and the middle area S4. The structure located in the middle area S4, such as, but not limited to, the core layer 200, the first metal layer 201, the second metal layer 202, the third metal layer 203, the fourth metal layer 204, the fifth metal layer 205 and the sixth metal layer 206, can be included in the final product structure of the printed circuit board 20. The structure located in the board edge area S3 does not constitute the final product structure of the printed circuit board 20.

[0064] The core layer 200 can be any commonly used core layer in the art, and its thickness and material can be set according to specific needs. The core layer 200 has a first surface 200a and a second surface 200b opposite to the first surface 200a.

[0065] The first metal layer 201 may be located on the first surface 200a of the core layer 200. The material of the first metal layer 201 disposed in the middle region S4 may be any suitable metal in the art, such as, but not limited to, copper. The material of the first metal layer 201 disposed in the board edge region S3 may include any suitable non-metallic material. The thickness of the first metal layer 201 may be set according to specific needs.

[0066] The second metal layer 202 may be disposed close to the first metal layer 201 and away from the first surface 200a of the core layer 200. The material of the second metal layer 202 disposed in the middle region S4 may be any suitable metal in the art, such as, but not limited to, copper. The material of the second metal layer 202 disposed in the board edge region S3 may include any suitable non-metallic material. The thickness of the second metal layer 202 may be set according to specific needs. The thickness and material of the second metal layer 202 may be the same as or different from the first metal layer 201.

[0067] The third metal layer 203 may be disposed close to the second metal layer 202 and away from the first metal layer 201. The material of the third metal layer 203 disposed in the middle region S4 may be any suitable metal in the art, for example, but not limited to, copper. The material of the third metal layer 203 disposed in the board edge region S3 may include any suitable non-metallic material. The thickness of the third metal layer 203 may be set according to specific needs. The thickness and material of the third metal layer 203 may be the same as or different from the first metal layer 201.

[0068] The fourth metal layer 204 may be located on the second surface 200b of the core layer 200. The material of the fourth metal layer 204 disposed in the middle region S4 may be any suitable metal in the art, such as, but not limited to, copper. The material of the fourth metal layer 204 disposed in the board edge region S3 may include any suitable non-metallic material. The fourth metal layer 204 may be formed simultaneously with the first metal layer 201.

[0069] The fifth metal layer 205 may be disposed close to the fourth metal layer 204 and away from the second surface 200b of the core layer 200. The material of the fourth metal layer 204 disposed in the middle region S4 may be any suitable metal in the art, for example, but not limited to, copper. The material of the fourth metal layer 204 disposed in the board edge region S3 may include any suitable non-metallic material. The fifth metal layer 205 is formed simultaneously with the second metal layer 202 in correspondence.

[0070] The sixth metal layer 206 may be disposed close to the fifth metal layer 205 and away from the fourth metal layer 204. The material of the sixth metal layer 206 disposed in the middle region S4 may be any suitable metal in the art, such as, but not limited to, copper. The material of the sixth metal layer 206 disposed in the board edge region S3 may include any suitable non-metallic material. The sixth metal layer 206 is formed simultaneously with the third metal layer 203.

[0071] The first metal layer 201 may have a first metal structure 211. The first metal structure 211 may be disposed on the first metal layer 201 in the edge region S3 by any suitable method, such as, but not limited to, etching or electroplating. The first metal structure 211 may be made of copper. The first metal structure 211 may also be made of any suitable metal material. In the plane where the X direction and the Z direction are located, the first metal structure 211 may be in a circular shape. The first metal structure 211 may also be in any suitable shape, such as, but not limited to, a triangle or a square. The size of the circular first metal structure 211 disposed in the board edge region S3 of the printed circuit board 20 may be set according to specific needs.

[0072] The second metal layer 202 may have a second metal structure 213. The second metal structure 213 may be disposed on the second metal layer 202 in the edge region S3 by any suitable method, such as, but not limited to, etching or electroplating. The second metal structure 213 may be made of copper. The second metal structure 213 may also be made of any suitable metal material. In the plane where the X direction and the Z direction are located, the second metal structure 213 may be annular. The second metal structure 213 may also be in any suitable shape, such as, but not limited to, a triangle or a square. The size of the annular second metal structure 213 disposed in the board edge region S3 of the printed circuit board 20 may be set according to specific needs, and it may be smaller than the size of the first metal structure 211. In other embodiments of the present application, the size of the first metal structure 211 may be smaller than the size of the second metal structure 213.

[0073] The third metal layer 203 may have a third metal structure 215. The third metal structure 215 may be disposed on the third metal layer 203 in the edge region S3 by any suitable method, such as, but not limited to, etching or electroplating. The third metal layer 203 may be made of copper. The third metal layer 203 may also be made of any suitable metal material. In the plane where the X direction and the Z direction are located, the third metal structure 215 may be a solid circle. The third metal structure 215 may also be in any suitable shape, such as, but not limited to, a triangle or a circular ring. The ring mark with the smallest diameter among the first metal structure 211, the second metal structure 113 and the third metal structure 215 may be a solid circle. The size of the circular third metal structure 215 disposed in the board edge region S3 of the printed circuit board 20 may be set according to specific needs, and it may be smaller than the size of the second metal structure 213. In other embodiments of the present application, the size of the second metal structure 213 may be smaller than the size of the third metal structure 215.

[0074] The center E1 of the first metal structure 211, the center E2 of the second metal structure 213, and the center E3 of the third metal structure 215 are all on a first straight line F1 perpendicular to the first surface 200a. The first straight line F1 is parallel to the Y direction. The first metal structure 211 and the second metal structure 213 are along the length direction of the printed circuit board 20 in the projection plane of the first surface 200a (i.e., the plane where the X direction and the Z direction are located), that is, the spacing P1 in the X direction is equal to the first preset offset value minus the erosion amount of the first metal layer 201 and the erosion amount of the second metal layer 202, and the second metal structure 213 and the third metal structure 215 are along the length direction of the printed circuit board 20 in the projection plane of the first surface 200a (i.e., the plane where the X direction and the Z direction are located), that is, the spacing P1 in the X direction is equal to the first preset offset value minus the erosion amount of the second metal layer 202 and the erosion amount of the third metal layer 203. The first preset offset value is a first value that allows interlayer offset between the first metal layer 201 and the second metal layer 202. The first preset offset value is also a first value that allows interlayer offset between the second metal layer 202 and the third metal layer 203. The first value can be set according to specific needs. For example, the first preset offset value can be about 50 microns.

[0075] The first metal structure 211, the second metal structure 213, and the third metal structure 215 may constitute a layer deviation detection area N1. After the printed circuit board 20 is formed, in order to detect the interlayer deviation between the metal layers in the printed circuit board 20, the printed circuit board 20 may be irradiated with X-rays. The adjacent metal structures in the layer deviation detection area N1, that is, whether there is tangency or intersection between the first metal structure 211 and the second metal structure 213, and between the second metal structure 213 and the third metal structure 215, may be visually or machine-observed. If there is tangency or intersection, it means that the interlayer deviation between the metal layers where the two metal structures that are tangent or intersecting are located exceeds the maximum value allowed.

[0076] The printed circuit board 20 may include at least one layer deviation detection area N1. To further improve the detection accuracy, the printed circuit board 20 may preferably include four layer deviation detection areas N1, wherein two layer deviation detection areas are symmetrically arranged at the upper end and the lower end of the left side of the printed circuit board 20, and the other two layer deviation detection areas are symmetrically arranged at the upper end and the lower end of the right side of the printed circuit board, such as Figure 2B shown.

[0077] The printed circuit board 20 may further include an insulating layer 220 disposed between the first metal layer 201 and the second metal layer 202, between the second metal layer 202 and the third metal layer 203, between the fourth metal layer 204 and the fifth metal layer 205, between the fifth metal layer 205 and the sixth metal layer 206, on the surface of the third metal layer 203, and on the surface of the sixth metal layer 206. The material of the insulating layer 220 may be an insulating material commonly used in the art, such as, but not limited to, resin. The insulating layer 220 located at the outermost layer may be provided with one or more metal pads, which may be made of any suitable metal material, such as, but not limited to, nickel or gold, to respectively achieve electrical connection with the third metal layer 203 close to the uppermost side of the printed circuit board 20 and the sixth metal layer 206 close to the lowermost side of the printed circuit board 20.

[0078] The printed circuit board 20 may further include a through hole 230 penetrating the core layer 200 , the first metal layer 201 , the second metal layer 202 , the third metal layer 203 , the fourth metal layer 204 , the fifth metal layer 205 , the sixth metal layer 206 and the insulating layer 220 .

[0079] Certain manufacturing processes of the printed circuit board 20 will cause the metal layer to expand or contract to a certain extent. The layer deviation detection area N1 provided in the embodiment of the present application, which is composed of the first metal structure 211, the second metal structure 213 and the third metal structure 215, sets a preset offset value considering the etching amount of different metal layers, and can perform inter-layer deviation detection with higher precision and accuracy.

[0080] Furthermore, in order to obtain interlayer offset detection with higher precision and accuracy, the layer deviation detection area N1 may be further provided to further include a fourth metal structure 217, a fifth metal structure 219, and a sixth metal structure 221. The fourth metal structure 217 may be located on the second metal layer 202. The fifth metal structure 219 may be located on the fourth metal layer 204. The sixth metal structure 221 may be located on the sixth metal layer 206. In other embodiments of the present application, the fourth metal structure 217 may be located on one of the first metal layer 201, the second metal layer 202, and the third metal layer 203. The fifth metal structure 219 and the sixth metal structure 221 are respectively located on two of the fourth metal layer 204, the fifth metal layer 205, and the sixth metal layer 206 formed not corresponding to the metal layer having the fourth metal structure 217.

[0081] The center E4 of the fourth metal structure 217, the center E5 of the fifth metal structure 219, and the center E6 of the sixth metal structure 221 are all on the second straight line F2 perpendicular to the first surface 200a. The second straight line F2 is parallel to the Y direction and is appropriately spaced apart from the first straight line F1. The fourth metal structure 217 and the fifth metal structure 219 are located in the projection plane of the first surface 200a (i.e., the plane where the X direction and the Z direction are located) along the length direction of the printed circuit board 20, i.e., the spacing P1 in the X direction is equal to the first preset offset value minus the erosion amount of the second metal layer 202 and the erosion amount of the fourth metal layer 204. The fifth metal structure 219 and the sixth metal structure 221 are located in the projection plane of the first surface 200a (i.e., the plane where the X direction and the Z direction are located) along the length direction of the printed circuit board 20, i.e., the spacing P1 in the X direction is equal to the first preset offset value minus the erosion amount of the fourth metal layer 204 and the erosion amount of the sixth metal layer 206.

[0082] By further providing a fourth metal structure 217 , a fifth metal structure 219 and a sixth metal structure 221 , the embodiment of the present application can further improve the accuracy of inter-layer detection.

[0083] In order to obtain interlayer offset detection with higher precision and accuracy, the layer deviation detection area N1 may be further configured to further include a seventh metal structure 223, an eighth metal structure 225, and a ninth metal structure 227. The seventh metal structure 223 may be located on the third metal layer 203. The eighth metal structure 225 may be located on the fourth metal layer 204. The ninth metal structure 227 may be located on the fifth metal layer 205. In other embodiments of the present application, the seventh metal structure 223 may be located on one of the remaining two metal layers of the first metal layer 201, the second metal layer 202, and the third metal layer 203, excluding the metal layer having the fourth metal structure 217, and the eighth metal structure 225 and the ninth metal structure 227 may be located on two of the fourth metal layer 204, the fifth metal layer 205, and the sixth metal layer 206, which are formed not corresponding to the metal layer having the seventh metal structure 223, respectively.

[0084] The center E7 of the seventh metal structure 223, the center E8 of the eighth metal structure 225, and the center E9 of the ninth metal structure 227 are all on the third straight line F3 perpendicular to the first surface 200a. The third straight line F3 is parallel to the Y direction and is appropriately spaced from the second straight line F2. The seventh metal structure 223 and the eighth metal structure 225 are spaced along the length direction of the printed circuit board 20 in the projection plane of the first surface 200a (i.e., the plane where the X direction and the Z direction are located), that is, the spacing P1 in the X direction is equal to the first preset offset value minus the sum of the erosion amounts of the metal layers where the seventh metal structure 223 and the eighth metal structure 225 are located. The eighth metal structure 225 and the ninth metal structure 227 are spaced along the length direction of the printed circuit board 20 in the projection plane of the first surface 200a (i.e., the plane where the X direction and the Z direction are located), that is, the spacing P1 in the X direction is equal to the first preset offset value minus the sum of the erosion amounts of the metal layers where the eighth metal structure 225 and the ninth metal structure 227 are located.

[0085] Interlayer detection between multilayer boards often results in redundant and complicated detection processes due to too many layers, and the detection results are not accurate enough and the detection is difficult. In the embodiment of the present application, three different metal layers located on the first side of the core layer 200 are selected as the first group for detection; one of the three different metal layers located on the first side of the core layer 200 and two metal layers located on the second side of the core layer 200 that are not formed corresponding to the selected metal layer are selected as the second group for detection; and one of the remaining two metal layers except for one metal layer with two metal structures among the three metal layers located on the first side of the core layer 200 and two metal layers located on the second side of the core layer 200 that are not formed corresponding to the selected metal layer are further selected as the third group for detection, thereby achieving the purpose of layer deviation detection of multilayer boards in the simplest and most efficient form and with the most accurate effect.

[0086] In order to obtain interlayer offset detection with higher precision and accuracy, the layer deviation detection area N1 may be further configured to further include a tenth metal structure 231, an eleventh metal structure 233, and a twelfth metal structure 235. The tenth metal structure 231 may be located on the first metal layer 201. The eleventh metal structure 233 may be located on the second metal layer 202. The twelfth metal structure 235 may be located on the third metal layer 203. In other embodiments of the present application, the tenth metal structure 231, the eleventh metal structure 233, and the twelfth metal structure 235 may be located in any one of the fourth metal layer 204, the fifth metal layer 205, and the sixth metal layer 206, respectively.

[0087] The center E10 of the tenth metal structure 231, the center E11 of the eleventh metal structure 233, and the center E12 of the twelfth metal structure 235 are all on a fourth straight line perpendicular to the first surface 200a. The fourth straight line may be at the same position as the first straight line F1 in the X direction. The spacing P2 (not shown in the figure, the measurement method of P2 is the same as P1) between the tenth metal structure 231 and the eleventh metal structure 233 along the length direction of the printed circuit board 20 in the projection plane of the first surface 200a (i.e., the plane where the X direction and the Z direction are located) is equal to the sum of the second preset offset value minus the amount of erosion of the metal layer where the tenth metal structure 231 and the eleventh metal structure 233 are located. The spacing P2 between the eleventh metal structure 233 and the twelfth metal structure 235 along the length direction of the printed circuit board 20 in the projection plane of the first surface 200a (i.e., the plane where the X direction and the Z direction are located) is equal to the sum of the amount of erosion of the metal layer where the eleventh metal structure 233 and the twelfth metal structure 235 are located in the X direction. The second preset offset value is a second value that allows interlayer offset between two adjacent metal layers. The second preset offset value may be about 65 microns. By setting a second preset offset value different from the first preset offset value, the embodiment of the present application can roughly determine the range of layer offset after performing a layer offset detection on the same printed circuit board 20. For example, if there is no tangency or intersection at the tenth metal structure 231, the eleventh metal structure 233 and the twelfth metal structure 235, but there is tangency or intersection at the first metal structure 211, the second metal structure 213 and the third metal structure 215, it can be determined that the layer offset of the corresponding layer of the printed circuit board 20 where tangency or intersection occurs is greater than the first preset offset value, but less than the second preset offset value. If there is also tangency or intersection at the tenth metal structure 231, the eleventh metal structure 233 and the twelfth metal structure 235, it can be determined that the layer offset of the corresponding layer of the printed circuit board 20 where tangency or intersection occurs is greater than the second preset offset value.

[0088] The layer deviation detection area N1 may further include a thirteenth metal structure 237, a fourteenth metal structure 239, and a fifteenth metal structure 241. The thirteenth metal structure 237 may be located on the metal layer having the fourth metal structure 217. The fourteenth metal structure 239 may be located on the metal layer having the fifth metal structure 219. The fifteenth metal structure 241 may be located on the metal layer having the sixth metal structure 221.

[0089] The center E13 of the thirteenth metal structure 237, the center E14 of the fourteenth metal structure 239, and the center E15 of the fifteenth metal structure are all on a fifth straight line perpendicular to the first surface 200a. The fifth straight line may be at the same position as the second straight line F2 in the X direction. The spacing P2 (not shown in the figure, the measurement method of P2 is the same as P1) between the thirteenth metal structure 237 and the fourteenth metal structure 239 along the length direction of the printed circuit board 20 in the projection plane of the first surface 200a (i.e., the plane where the X direction and the Z direction are located) is equal to the sum of the second preset offset value minus the amount of erosion of the metal layer where the thirteenth metal structure 237 and the fourteenth metal structure 239 are located. The spacing P2 between the fourteenth metal structure 239 and the fifteenth metal structure 241 along the length direction of the printed circuit board 20 in the projection plane of the first surface 200a (i.e., the plane where the X direction and the Z direction are located) is equal to the sum of the amount of erosion of the metal layer where the fourteenth metal structure 239 and the fifteenth metal structure 241 are located in the X direction.

[0090] Layer deviation detection area N1 may further include a sixteenth metal structure 243, a seventeenth metal structure 245, and an eighteenth metal structure 247. The sixteenth metal structure 243 may be located on the metal layer having the seventh metal structure 223. The seventeenth metal structure 245 may be located on the metal layer having the eighth metal structure 225. The eighteenth metal structure 247 may be located on the metal layer having the ninth metal structure 227.

[0091] The center E16 of the sixteenth metal structure 243, the center E17 of the seventeenth metal structure 245, and the center E18 of the eighteenth metal structure 247 are all on the sixth straight line perpendicular to the first surface 200a. The fifth straight line may be at the same position as the third straight line F3 in the X direction. The sixteenth metal structure 243 and the seventeenth metal structure 245 in the projection plane of the first surface 200a (i.e., the plane where the X direction and the Z direction are located) along the length direction of the printed circuit board 20, i.e., the X direction, the spacing P2 (not shown in the figure, the measurement method of P2 is the same as P1) is equal to the sum of the second preset offset value minus the amount of bite of the metal layer where the sixteenth metal structure 243 and the seventeenth metal structure 245 are located. The seventeenth metal structure 245 and the eighteenth metal structure 247 in the projection plane of the first surface 200a (i.e., the plane where the X direction and the Z direction are located) along the length direction of the printed circuit board 20, i.e., the X direction, the spacing P2 is equal to the sum of the second preset offset value minus the amount of bite of the metal layer where the seventeenth metal structure 245 and the eighteenth metal structure 247 are located.

[0092] The layer deviation detection area N1 may further include a nineteenth metal structure 249, a twentieth metal structure 251, and a twenty-first metal structure 253. The nineteenth metal structure 249 may be located on the first metal layer 201. The twentieth metal structure 251 may be located on the second metal layer 202. The twenty-first metal structure 253 may be located on the third metal layer 203. In other embodiments of the present application, the nineteenth metal structure 249, the twentieth metal structure 251, and the twenty-first metal structure 253 may be located in any one of the fourth metal layer 204, the fifth metal layer 205, and the sixth metal layer 206, respectively.

[0093] The center E19 of the nineteenth metal structure 249, the center E20 of the twentieth metal structure 251, and the center E21 of the twenty-first metal structure 253 are all on the seventh straight line perpendicular to the first surface 200a. The seventh straight line may be at the same position as the first straight line F1 in the X direction. The spacing P3 (not shown in the figure, the measurement method of P3 is the same as P1) of the nineteenth metal structure 249 and the twenty-first metal structure 251 along the length direction of the printed circuit board 20 in the projection plane of the first surface 200a (i.e., the plane where the X direction and the Z direction are located) is equal to the sum of the third preset offset value minus the amount of erosion of the metal layer where the nineteenth metal structure 249 and the twenty-first metal structure 251 are located. The spacing P3 of the twentieth metal structure 251 and the twenty-first metal structure 253 along the length direction of the printed circuit board 20 in the projection plane of the first surface 200a (i.e., the plane where the X direction and the Z direction are located) is equal to the sum of the third preset offset value minus the amount of erosion of the metal layer where the twentieth metal structure 251 and the twenty-first metal structure 253 are located. The third preset offset value is a third value that allows interlayer offset between two adjacent metal layers. The third preset offset value may be about 75 microns. The first preset offset value, the second preset offset value, and the third preset offset value may be different. The third preset offset value may be greater than the second preset offset value, and the second preset offset value may be greater than the first preset offset value. By setting a third preset offset value that is different from the first preset offset value and the second preset offset value, the embodiment of the present application can roughly determine the range of the layer deviation after performing a layer deviation detection on the same printed circuit board 20. For example, if there is no tangency or intersection at the nineteenth metal structure 249, the twentieth metal structure 251, and the twenty-first metal structure 253, but there is tangency or intersection at the tenth metal structure 231, the eleventh metal structure 233, and the twelfth metal structure 235, it can be determined that the layer deviation of the corresponding layer of the printed circuit board 20 where the tangency or intersection occurs is greater than the second preset offset value, but less than the third preset offset value.

[0094] The layer deviation detection area N1 may further include a twenty-second metal structure 255, a twenty-third metal structure 257, and a twenty-fourth metal structure 259. The twenty-second metal structure 255 may be located on the metal layer having the fourth metal structure 217. The twenty-third metal structure 257 may be located on the metal layer having the fifth metal structure 219. The twenty-fourth metal structure 259 may be located on the metal layer having the sixth metal structure 221.

[0095] The center E22 of the twenty-second metal structure 255, the center E23 of the twenty-third metal structure 257, and the center E24 of the twenty-fourth metal structure 259 are all on the eighth straight line perpendicular to the first surface 200a. The eighth straight line may be at the same position as the second straight line F2 in the X direction. The spacing P3 (not shown in the figure, the measurement method of P3 is the same as P1) of the twenty-second metal structure 255 and the twenty-third metal structure 257 in the projection plane of the first surface 200a (i.e., the plane where the X direction and the Z direction are located) along the length direction of the printed circuit board 20, i.e., in the X direction is equal to the sum of the third preset offset value minus the amount of erosion of the metal layer where the twenty-second metal structure 255 and the second third metal structure 257 are located. The spacing P3 of the twenty-third metal structure 257 and the twenty-fourth metal structure 259 in the projection plane of the first surface 200a (i.e., the plane where the X direction and the Z direction are located) along the length direction of the printed circuit board 20, i.e., in the X direction is equal to the sum of the third preset offset value minus the amount of erosion of the metal layer where the twenty-third metal structure 257 and the second fourth metal structure 259 are located.

[0096] The layer deviation detection area N1 may further include a twenty-fifth metal structure 261, a twenty-sixth metal structure 263, and a twenty-seventh metal structure 265. The twenty-fifth metal structure 261 may be located on the metal layer having the seventh metal structure 223. The twenty-sixth metal structure 263 may be located on the metal layer having the eighth metal structure 225. The twenty-seventh metal structure 265 may be located on the metal layer having the ninth metal structure 227.

[0097] The center E25 of the twenty-fifth metal structure 261, the center E26 of the twenty-sixth metal structure 263, and the center E27 of the twenty-seventh metal structure 265 are all on the ninth straight line perpendicular to the first surface 200a. The ninth straight line may be at the same position as the third straight line F3 in the X direction. The spacing P3 (not shown in the figure, the measurement method of P3 is the same as P1) between the twenty-fifth metal structure 261 and the second metal structure 263 in the projection plane of the first surface 200a (i.e., the plane where the X direction and the Z direction are located) along the length direction of the printed circuit board 20, i.e., in the X direction, is equal to the sum of the third preset offset value minus the amount of erosion of the metal layer where the twenty-fifth metal structure 261 and the second metal structure 263 are located. The spacing P3 between the twenty-sixth metal structure 263 and the second metal structure 265 in the projection plane of the first surface 200a (i.e., the plane where the X direction and the Z direction are located) along the length direction of the printed circuit board 20, i.e., in the X direction, is equal to the sum of the third preset offset value minus the amount of erosion of the metal layer where the twenty-sixth metal structure 263 and the second metal structure 265 are located.

[0098] The embodiment of the present application designs three different preset offset value graphic detections to make the layer deviation detection have a more detailed and flexible detection effect, thereby improving the accuracy and flexibility of the layer deviation detection. At the same time, for the interlayer deviation detection between printed circuit boards with a large number of layers, especially more than six layers, the embodiment of the present application selects three different metal layers located on the first side of the core layer 200 as the first group for detection; selects one of the three different metal layers located on the first side of the core layer 200, and two metal layers located on the second side of the core layer 200 that are not formed corresponding to the selected metal layer as the second group for detection; and further selects one of the remaining two metal layers of the three metal layers located on the first side of the core layer 200, excluding one metal layer with two metal structures, and two metal layers located on the second side of the core layer 200 that are not formed corresponding to the selected metal layer as the third group for detection, thereby achieving the purpose of multilayer board layer deviation detection in the simplest and most efficient form and with the most accurate effect.

[0099] The embodiment of the present application also provides a method for detecting the position deviation between layers of a printed circuit board. The method includes providing a printed circuit board provided according to the embodiment of the present application, and then using X-rays to irradiate the layer deviation detection area of ​​the printed circuit board to observe whether adjacent metal structures in the layer deviation detection area are tangent or intersecting. If there is tangency or intersection, it is determined that the layer deviation of the corresponding metal layer where the tangency or intersection occurs exceeds the allowable range, and the printed circuit board is unqualified. If the metal structure is offset, but no tangency or intersection has occurred, it is determined that the layer deviation of the corresponding metal layer does not exceed the allowable range, and the printed circuit board is qualified.

[0100] The method may also include observing whether metal structures with the same preset offset value are tangent or intersecting. Assuming that the third preset offset value is greater than the second preset offset value, and the second preset offset value is greater than the first preset offset value, it is possible to first observe whether the metal structure with the first preset offset value is tangent or intersecting. If there is no tangent or intersection, it is determined that the layer bias of the printed circuit board meets the first preset offset value. If the metal structure with the first preset offset value is tangent or intersecting, it is possible to continue to observe whether the metal structure with the second preset offset value is tangent or intersecting. If the metal structure with the second preset offset value is not tangent or intersecting, it is determined that the layer bias of the printed circuit board meets the second preset offset value. If the metal structure with the second preset offset value is tangent or intersecting, it is possible to observe whether the metal structure with the third preset offset value is tangent or intersecting. If the metal structure with the third preset offset value is not tangent or intersecting, it is determined that the layer bias of the printed circuit board meets the third preset offset value. If the metal structure with the third preset offset value is tangent or intersecting, it is determined that the layer bias of the printed circuit board is large and does not meet the third preset offset value.

[0101] The method for detecting interlayer position deviation of a printed circuit board provided in the embodiment of the present application can quickly identify whether a printed circuit board with a large number of layers has layer deviation simply by illuminating the layer deviation detection area of ​​the printed circuit board, and can generally determine the approximate circumstances in which the layer deviation has occurred, thereby having the advantages of high detection efficiency and accurate detection results.

[0102] The technical content and technical features of this application have been disclosed as above, but those skilled in the art may still make various substitutions and modifications based on the teachings and disclosures of this application without departing from the spirit of this application. Therefore, the protection scope of this application should not be limited to the contents disclosed in the embodiments, but should include various substitutions and modifications without departing from this application, and be covered by the claims of this application.

Claims

1. A printed circuit board, characterized in that: It includes: Core layer, A first metal layer is located on a first surface of the core layer, and the first metal layer has a first metal structure. A second metal layer is disposed close to the first metal layer and away from the first surface of the core layer, and the second metal layer has a second metal structure. A third metal layer is located on a second surface of the core layer, the second surface is opposite to the first surface, a fourth metal layer, disposed close to the third metal layer and away from the second surface of the core layer, The first metal structure and the second metal structure constitute a layer deviation detection area, the center of the first metal structure and the center of the second metal structure are both on a first straight line perpendicular to the first surface, and the spacing between the first metal structure and the second metal structure in the projection plane of the first surface along the length direction of the printed circuit board is equal to a first preset offset value minus the bite amount of the first metal layer and the bite amount of the second metal layer, and the first preset offset value is a first value that allows interlayer deviation between the first metal layer and the second metal layer; The printed circuit board has a length along the X direction, a height along the Y direction perpendicular to the X direction, and a width along the Z direction perpendicular to the plane where the X direction and the Y direction are located; and the bite amount is the change in the dimension along the X direction in the plane where the X direction and the Z direction are located after the metal layer expands or contracts.

2. The printed circuit board according to claim 1, characterized in that The third metal layer is formed simultaneously with the first metal layer in correspondence, and the fourth metal layer is formed simultaneously with the second metal layer in correspondence, wherein the layer deviation detection area further includes a third metal structure and a fourth metal structure, the third metal structure is located on one of the first metal layer and the second metal layer, and the fourth metal structure is located on one of the third metal layer and the fourth metal layer that is not formed corresponding to the metal layer having the third metal structure, Among them, the center of the third metal structure and the center of the fourth metal structure are both on a second straight line perpendicular to the first surface, and the distance between the third metal structure and the fourth metal structure in the projection plane of the first surface along the length direction of the printed circuit board is equal to the first preset offset value minus the corrosion amount of the metal layer where the third metal structure is located and the corrosion amount of the metal layer where the fourth metal structure is located.

3. The printed circuit board according to claim 1 or 2, characterized in that The printed circuit board includes four layer deviation detection areas, two of which are symmetrically arranged at the upper and lower ends of the left side of the printed circuit board, and the other two are symmetrically arranged at the upper and lower ends of the right side of the printed circuit board.

4. A printed circuit board, characterized in that: It includes: Core layer, A first metal layer is located on a first surface of the core layer, and the first metal layer has a first metal structure. A second metal layer is disposed close to the first metal layer and away from the first surface of the core layer, and the second metal layer has a second metal structure. A third metal layer is disposed close to the second metal layer and away from the first metal layer, and the third metal layer has a third metal structure. a fourth metal layer, located on a second surface of the core layer, the second surface being opposite to the first surface, a fifth metal layer, disposed close to the fourth metal layer and away from the second surface of the core layer, and a sixth metal layer, disposed close to the fifth metal layer and away from the fourth metal layer, wherein the first metal structure, the second metal structure and the third metal structure constitute a layer deviation detection area, the centers of the first metal structure, the second metal structure and the third metal structure are all on a first straight line perpendicular to the first surface, and the spacing between the first metal structure and the second metal structure in the projection plane of the first surface along the length direction of the printed circuit board and the spacing between the second metal structure and the third metal structure in the projection plane of the first surface along the length direction of the printed circuit board are respectively equal to the sum of the first preset offset value minus the bite amount of the metal layer where the corresponding metal structure is located, and the first preset offset value is a first value that allows interlayer deviation to occur between two adjacent metal layers; The printed circuit board has a length along the X direction, a height along the Y direction perpendicular to the X direction, and a width along the Z direction perpendicular to the plane where the X direction and the Y direction are located; and the bite amount is the change in the dimension along the X direction in the plane where the X direction and the Z direction are located after the metal layer expands or contracts.

5. The printed circuit board according to claim 4, characterized in that The fourth metal layer is formed simultaneously with the first metal layer, the fifth metal layer is formed simultaneously with the second metal layer, and the sixth metal layer is formed simultaneously with the third metal layer. The layer deviation detection area further includes a fourth metal structure, a fifth metal structure and a sixth metal structure, the fourth metal structure is located on one of the first metal layer, the second metal layer and the third metal layer, the fifth metal structure and the sixth metal structure are respectively located on two of the fourth metal layer, the fifth metal layer and the sixth metal layer which are not formed corresponding to the metal layer having the fourth metal structure, Among them, the center of the fourth metal structure, the center of the fifth metal structure and the center of the sixth metal structure are all on a second straight line perpendicular to the first surface, and the distance between the fourth metal structure and the fifth metal structure in the projection plane of the first surface along the length direction of the printed circuit board and the distance between the fifth metal structure and the sixth metal structure in the projection plane of the first surface along the length direction of the printed circuit board are respectively equal to the first preset offset value minus the sum of the corrosion amount of the metal layer where the corresponding metal structure is located.

6. The printed circuit board according to claim 5, characterized in that The layer deviation detection area also includes a seventh metal structure, an eighth metal structure and a ninth metal structure, the seventh metal structure is located on one of the remaining two metal layers among the first metal layer, the second metal layer and the third metal layer, excluding the metal layer having the fourth metal structure, the eighth metal structure and the ninth metal structure are respectively located on two of the fourth metal layer, the fifth metal layer and the sixth metal layer formed not corresponding to the metal layer having the seventh metal structure, Among them, the center of the seventh metal structure, the center of the eighth metal structure and the center of the ninth metal structure are all on a third straight line perpendicular to the first surface, and the spacing between the seventh metal structure and the eighth metal structure in the projection plane of the first surface along the length direction of the printed circuit board and the spacing between the seventh metal structure and the ninth metal structure in the projection plane of the first surface along the length direction of the printed circuit board are respectively equal to the sum of the first preset offset value minus the bite amount of the metal layer where the corresponding metal structure is located.

7. The printed circuit board according to claim 6, characterized in that The layer deviation detection area also includes: a tenth metal structure, located on the first metal layer, an eleventh metal structure located on the second metal layer, and a twelfth metal structure, located on the third metal layer, Among them, the center of the tenth metal structure, the center of the eleventh metal structure and the center of the twelfth metal structure are all on a fourth straight line perpendicular to the first surface, and the spacing between the tenth metal structure and the eleventh metal structure in the projection plane of the first surface along the length direction of the printed circuit board and the spacing between the eleventh metal structure and the twelfth metal structure in the projection plane of the first surface along the length direction of the printed circuit board are respectively equal to the sum of the second preset offset value minus the amount of bite of the metal layer where the corresponding metal structure is located, and the second preset offset value is a second value that allows interlayer offset to occur between two adjacent metal layers.

8. The printed circuit board according to claim 7, characterized in that The layer deviation detection area also includes a thirteenth metal structure, a fourteenth metal structure and a fifteenth metal structure. The thirteenth metal structure is located on the metal layer having the fourth metal structure, the fourteenth metal structure is located on the metal layer having the fifth metal structure, and the fifteenth metal structure is located on the metal layer having the sixth metal structure. The center of the thirteenth metal structure, the center of the fourteenth metal structure and the center of the fifteenth metal structure are all on a fifth straight line perpendicular to the first surface, and The spacing between the thirteenth metal structure and the fourteenth metal structure in the projection plane of the first surface along the length direction of the printed circuit board and the spacing between the fourteenth metal structure and the fifteenth metal structure in the projection plane of the first surface along the length direction of the printed circuit board are respectively equal to the sum of the second preset offset value minus the amount of corrosion of the metal layer where the corresponding metal structure is located.

9. The printed circuit board according to claim 8, characterized in that The layer deviation detection area also includes a sixteenth metal structure, a seventeenth metal structure and an eighteenth metal structure. The sixteenth metal structure is located on the metal layer having the seventh metal structure, the seventeenth metal structure is located on the metal layer having the eighth metal structure, and the eighteenth metal structure is located on the metal layer having the ninth metal structure. The center of the sixteenth metal structure, the center of the seventeenth metal structure and the center of the eighteenth metal structure are all on a sixth straight line perpendicular to the first surface, and The spacing between the sixteenth metal structure and the seventeenth metal structure in the projection plane of the first surface along the length direction of the printed circuit board and the spacing between the seventeenth metal structure and the eighteenth metal structure in the projection plane of the first surface along the length direction of the printed circuit board are respectively equal to the sum of the second preset offset value minus the amount of corrosion of the metal layer where the corresponding metal structure is located.

10. The printed circuit board according to claim 9, characterized in that The layer deviation detection area also includes: A nineteenth metal structure is located on the first metal layer, a twentieth metal structure located on the second metal layer, and A twenty-first metal structure is located on the third metal layer, Among them, the center of the nineteenth metal structure, the center of the twentieth metal structure and the center of the twenty-first metal structure are all on a seventh straight line perpendicular to the first surface, and the spacing between the nineteenth metal structure and the twentieth metal structure in the projection plane of the first surface along the length direction of the printed circuit board and the spacing between the twentieth metal structure and the twenty-first metal structure in the projection plane of the first surface along the length direction of the printed circuit board are respectively equal to the third preset offset value minus the sum of the bite amounts of the metal layers where the corresponding metal structures are located, and the third preset offset value is a third value that allows interlayer offset to occur between two adjacent metal layers.

11. The printed circuit board according to claim 10, characterized in that The layer deviation detection area further includes a twenty-second metal structure, a twenty-third metal structure and a twenty-fourth metal structure. The twenty-second metal structure is located on the metal layer having the fourth metal structure, the twenty-third metal structure is located on the metal layer having the fifth metal structure, and the twenty-fourth metal structure is located on the metal layer having the sixth metal structure. Among them, the center of the twenty-second metal structure, the center of the twenty-third metal structure and the center of the twenty-fourth metal structure are all on an eighth straight line perpendicular to the first surface, and the spacing between the twenty-second metal structure and the twenty-third metal structure in the projection plane of the first surface along the length direction of the printed circuit board and the spacing between the twenty-third metal structure and the twenty-fourth metal structure in the projection plane of the first surface along the length direction of the printed circuit board are respectively equal to the sum of the third preset offset value minus the amount of corrosion of the metal layer where the corresponding metal structure is located.

12. The printed circuit board according to claim 11, characterized in that The layer deviation detection area further includes a twenty-fifth metal structure, a twenty-sixth metal structure and a twenty-seventh metal structure. The twenty-fifth metal structure is located on the metal layer having the seventh metal structure, the twenty-sixth metal structure is located on the metal layer having the eighth metal structure, and the twenty-seventh metal structure is located on the metal layer having the ninth metal structure. Among them, the center of the twenty-fifth metal structure, the center of the twenty-sixth metal structure and the center of the twenty-seventh metal structure are all on a ninth straight line perpendicular to the first surface, and the spacing between the twenty-fifth metal structure and the twenty-sixth metal structure in the projection plane of the first surface along the length direction of the printed circuit board and the spacing between the twenty-sixth metal structure and the twenty-seventh metal structure in the projection plane of the first surface along the length direction of the printed circuit board are respectively equal to the sum of the third preset offset value minus the amount of corrosion of the metal layer where the corresponding metal structure is located.

13. The printed circuit board according to claim 12, characterized in that The first preset offset value, the second preset offset value and the third preset offset value are different.

14. The printed circuit board according to claim 13, characterized in that The first preset offset value is 50 micrometers, the second preset offset value is 65 micrometers, and the third preset offset value is 75 micrometers.

15. The printed circuit board according to any one of claims 4 to 14, wherein: All metal structures are in the shape of triangle, square or ring and are arranged in the board edge area of ​​the printed circuit board.

16. The printed circuit board according to claim 15, characterized in that The ring mark with the smallest diameter is a solid circle.

17. The printed circuit board according to any one of claims 4 to 14, characterized in that The printed circuit board includes four layer deviation detection areas, two of which are symmetrically arranged at the upper and lower ends of the left side of the printed circuit board, and the other two are symmetrically arranged at the upper and lower ends of the right side of the printed circuit board.

18. The printed circuit board according to any one of claims 4 to 14, characterized in that All metal structures are made of copper.

19. A method for detecting interlayer position deviation of a printed circuit board, characterized in that: It includes: Providing a printed circuit board as claimed in any one of claims 1 to 18, irradiating the printed circuit board with X-rays, Observe whether adjacent metal structures in the layer deviation detection area are tangent or intersecting.

20. The method for detecting interlayer position deviation of a printed circuit board according to claim 19, characterized in that Observing whether adjacent metal structures in the layer deviation detection area are tangent or intersecting includes: Observe whether there are tangencies or intersections between metal structures with the same preset offset value.

Images