Wiring board laminate

Abstract

To provide a wiring board laminate capable of conducting a continuity test before mounting a semiconductor chip.SOLUTION: A wiring board laminate includes a support, a first conductive layer provided on the upper surface of the support, and a wiring board provided on the upper surface of the first conductive layer, and has a structure including a wiring arranged on each layer of the wiring board, an electrode connected to the outside by exposing to the outside of the board among wirings, and a wiring net which is a conductor continuum that includes through electrodes for connecting wirings on respective layers. The wiring board laminate is possible to achieve both simple electrical inspection and fine wiring with a high yield.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a wiring board laminate including a wiring board on a support. [Background technology]

[0002] Semiconductor packages are assembled by electrically connecting semiconductor components and wiring boards via solder or other means. In recent years, semiconductor components have become more expensive as their functionality has increased, with technologies such as HBM (High Band Memory). For this reason, it is essential that the wiring boards on which semiconductor components are mounted are of good quality, and electrical inspection methods for wiring boards to ensure quality are extremely important.

[0003] Conventionally, the following two methods have been used for electrical inspection of wiring boards, and each method is used depending on the situation.

[0004] The first method is the IV method shown in Figure 1, in which a pair of electrical inspection probes 201a and 201b to which a certain DC voltage is applied are brought into contact with both ends of a first wiring net 41 formed on a wiring board 40, and the conductivity state of the first wiring net is determined by the ratio of the current to the voltage between the electrical inspection probes 201a and 201b, i.e., the electrical resistance value.

[0005] The above-mentioned wiring net refers to a series of electrically connected structures, including through electrodes that penetrate an insulating layer and electrodes that are provided on part of the wiring, in order to connect wiring that belongs to different conductor wiring layers in a wiring board.

[0006] The second method is a capacitance method, as shown in Figure 2, in which a pair of electrical inspection probes 201a and 201b to which an AC voltage is applied is used. The first electrical inspection probe 201a is brought into contact with a first electrode 41a constituting a first wiring net 41 formed on a wiring board 40, and the other electrical inspection probe 201b is brought into contact with an external electrode 300 provided outside the wiring board. The capacitance generated between the first wiring net 41 and the external electrode 300 at this time is used to determine the continuity of the first wiring net 41. Because the area of ​​the wiring differs between a case where there is no problem with the wiring, as shown in Figure 2(a), and a case where there is a problem such as a short circuit, as shown in Figure 2(b), the capacitance value C', which is recognized as a normal value based on prior knowledge, and the measured capacitance value C differ. This fact is utilized in wiring inspection.

[0007] The capacitance method has the advantage of being able to detect breaks in the target wiring and short-circuits with adjacent wiring at the same time, making it possible to significantly reduce the inspection time compared to the IV method.

[0008] In high-end semiconductor packages using expensive semiconductor components, the redistribution layer (RDL) is thin and difficult to handle. Therefore, during substrate fabrication, a wiring board is formed on a rigid support. To improve yield, fine wiring sections are formed as independent wiring sections without connecting them to other wiring sections. On the other hand, when electrical testing of wiring boards is performed using the capacitance method, a test probe is applied to one side of the wiring board, then to the other side, and the quality of the wiring is determined based on the obtained capacitance values. In other words, both sides of the wiring board must be exposed, which poses a challenge: electrical testing is difficult on wiring boards formed on a support.

[0009] On the other hand, in the fine wiring portion, only one electrode is exposed, and although electrical testing by electrical resistance is possible, the time required for testing is long because a probe must be brought into contact with each terminal, and the capacitance method is not suitable. When measuring a wiring board formed on a support by the capacitance method, one issue is that sandwiching the support increases the distance between the capacitor electrodes, which reduces the capacitance value and makes measurement difficult, so it is necessary to improve the accuracy of electrode-to-electrode measurement.

[0010] Another issue with micro-wiring substrates is that, to prevent the fine wiring from collapsing, the wiring thickness needs to be smaller than that of conventional substrates. However, the bonding electrodes for joining to other layers need to be plated thicker by the thickness of the resin layer, making it difficult to adjust the thickness of the bonding electrodes and wiring.

[0011] In response to the above problem, a prior document provides a laminated sheet comprising a support, a first conductive film provided on the upper surface of the support, an insulating film provided on the first conductive film, and a second conductive film provided on the upper surface of the insulating film, wherein the second conductive film is used to form a rewiring layer, and the first conductive film, second conductive film, and insulating film function as a capacitor for performing electrical testing of the rewiring layer, thereby enabling electrical testing of the rewiring layer formed on the upper surface of the support.

[0012] In the prior art, electrical testing is achieved by applying a voltage between the wiring in the redistribution layer and the first conductive film and measuring the capacitance. Here, electrical testing requires two probes to contact the wiring and measure the capacitance. However, in the structure of the laminate sheet, the first conductive film only has its side exposed at the end face of the laminate sheet, making it difficult to contact the probes.

[0013] Furthermore, one example of a rewiring layer formation process includes a process of forming a wiring pattern on a second conductive film and then removing the portion of the second conductive film that is not covered by the wiring pattern. In this case, the area of ​​the second conductive film is reduced, and the capacitance obtained by the first conductive film, the second conductive film, and the insulating film is reduced. In electrical wiring testing using capacitance, the quality of the wiring is determined by comparing it with a normal state, so it is desirable that the impact of variation in the obtained capacitance is small. However, in the above case, the obtained capacitance is small, so the impact of variation is large and the accuracy of the electrical testing is reduced. [Prior art documents] [Patent documents]

[0014] [Patent Document 1] International Publication No. 2020 / 129299 Summary of the Invention [Problem to be solved by the invention]

[0015] As described above, in the prior art, it was difficult to perform electrical testing by the capacitance method with high precision on a laminated substrate having fine wiring due to the structure of the substrate. [Means for solving the problem]

[0016] The present invention has been made in view of the above problems, and has as its object to provide a wiring board laminate in which fine wiring is arranged and which allows for easy high-precision electrical testing.

[0017] The wiring board laminate according to the present invention comprises a support, a first conductive layer provided on an upper surface of the support, and a wiring board provided on an upper surface of the first conductive layer, and when a continuum of conductors including wiring arranged on each layer of the wiring board, electrodes of the wiring exposed to the outside of the board for connection to the outside, and through electrodes for connecting the wiring of each layer is referred to as a wiring net, the wiring board comprises a first wiring net having electrodes exposed on at least one surface of the wiring board and electrically connected to the first conductive layer, and an electrode exposed on at least one surface of the wiring board and electrically connected to the first conductive layer, and a through electrode for connecting the first wiring net and the first conductive layer. and a third wiring net having an electrode exposed on only one side of the wiring substrate and electrically insulated from the first conductive layer and the first and second wiring nets by an insulating resin layer.

[0018] Further, the wiring board laminate of the present invention comprises a support, a first conductive layer provided on the upper surface of the support, and a wiring board provided on the upper surface of the first conductive layer. When a wiring net is defined as a continuum of conductors including wiring arranged in each layer of the wiring board, electrodes of the wiring exposed to the outside of the board for connection to the outside, and through electrodes for connecting the wiring of each layer, the wiring board is characterized by comprising: a first wiring net having an electrode exposed on at least one surface of the wiring board and electrically connected to the first conductive layer; a second wiring net having an electrode exposed on at least one surface of the wiring board, electrically connected to the first conductive layer and electrically connected to the first wiring net only through the first conductive layer; a third wiring net having an electrode exposed only on one side of the wiring board and electrically insulated from the first conductive layer and the first and second wiring nets by an insulating resin layer; and an electrode layer electrically insulated from the first insulating layer and all of the first, second, and second wiring nets, and having a portion exposed to the outside of the wiring board. [Effects of the Invention]

[0019] According to the present invention, it is possible to realize a wiring board laminate that allows for highly accurate electrical testing by the capacitance method before mounting a semiconductor chip and facilitates wiring formation. [Brief explanation of the drawings]

[0020] [Figure 1] FIG. 1 is a schematic diagram of an electrical inspection method for a wiring board using the IV method. [Figure 2] 1 is a schematic diagram of an electrical inspection method for a wiring board using a capacitance method. [Figure 3] 1A and 1B are schematic diagrams illustrating an example of a method for inspecting a wiring board laminate and wiring boards according to a first embodiment. [Figure 4] 5 is a schematic diagram showing a modified example of the wiring board inspection method according to the first embodiment. FIG. [Figure 5] FIG. 10 is a schematic view showing an example of a wiring board laminate according to a second embodiment. [Figure 6] 10 is a schematic view showing a modified example of the wiring board inspection method according to the second embodiment. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0021] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, the same elements or elements having the same functions will be designated by the same reference numerals, and redundant description will be omitted.

[0022] (First embodiment) [Structure of wiring board according to first embodiment] First, the structure of a wiring board laminate 1 according to the first embodiment will be described. Fig. 3 is a diagram illustrating the wiring board laminate 1 of this embodiment. As shown in Fig. 3, the wiring board laminate 1 includes a wiring board 40, a support 104, and a first conductive layer 101. The wiring board 40 includes a first wiring net 41, a second wiring net 42 electrically connected to the first wiring net 41, a third wiring net 43 electrically insulated from the first wiring net and the second wiring net, and at least one insulating resin layer 45.

[0023] The insulating resin layer 45 is formed of an insulating resin containing, for example, an epoxy resin or a polyimide resin as a main component. The insulating resin may be, for example, a thermosetting insulating resin or a photosensitive insulating resin. The thickness of the insulating resin layer 43 may be, for example, about 3 to 35 μm. The insulating resin layer 45 may contain a filler such as silica (SiO2). The insulating resin layer 45 may be entirely made of a build-up layer made of a thermosetting insulating resin or a photosensitive insulating resin, or may be made of a thermosetting insulating resin. The insulation resin and the photosensitive insulating resin build-up layer may be present together. After careful consideration, it was determined that the insulation of the insulator must have a resistance of 10 MΩ or more, because measurement errors become large when the insulation is less than 10 MΩ.

[0024] The first wiring net 41 and the second wiring net 42 are each formed by connecting wires 41b, 42b formed on the upper layer of the insulating resin layer 45, through-hole electrodes 41c, 42c formed through the insulating resin layer in the thickness direction to ensure electrical continuity between the wires isolated by the insulating resin layer, and electrodes 41a, 42a formed on the outermost insulating resin layer of the laminate substrate and exposed to the outside for contact with the outside of the laminate substrate. The wires 41b, 42b can be made of copper, for example. The thickness of the wires 41b, 42b can be, for example, approximately 1 to 15 μm.

[0025] On the outermost insulating resin layer 45 of the wiring substrate 40, one end of the first wiring net 41 and one end of the second wiring net 42 are disposed as a first electrode 41a and a second electrode 42a, respectively, and are exposed to the outside. Therefore, the multilayer wiring substrate of the present invention can be electrically connected to electronic components such as semiconductor chips via these electrodes. The first electrode and the second electrode may be protruding, flat, or recessed relative to the upper surface of the wiring substrate 40. The electrodes 41a and 42a may be made of copper, for example. The electrodes 41a and 42a may be formed by any suitable method, such as a well-known semi-additive method or subtractive method.

[0026] Furthermore, for surface protection and good electrical connection, the surfaces of the electrodes 41a and 42a may be coated with a metal such as Au, Ag, Cu, Al, or an alloy thereof, a metal composite such as Cu plated with Au, or a solder such as Sn, Sn-Pb, Sn-Ag, Sn-Cu, Sn-Ag-Cu, Sn-Bi, or Au.

[0027] Furthermore, the ends of the first wiring net 41 and the second wiring net 42 that are not electrodes are electrically connected to the first conductive layer 101 .

[0028] The third wiring net 43 is composed of a third wiring 43b formed on the upper layer of the insulating resin layer 45, a third through electrode 43c formed in the insulating resin layer 43, and a third electrode 43a formed further on the insulating resin layer 45 located on the outermost side of the wiring board 40. All of the components constituting the third wiring net 43 can be made of the same metal and by the same construction method as the first and second wiring nets 41 and 42. The third wiring net 43 is electrically insulated from the first conductive layer 101, the first wiring net 41, and the second wiring net 42.

[0029] For the first wiring net 41 and the second wiring net 42 configured as described above, by contacting the first electrical inspection probe 201a with the first electrode 41a and the second electrical inspection probe 201b with the second electrode 42a, it is possible to check for any breaks in the wiring by performing an electrical resistance test through the conductive layer 101.

[0030] Next, as shown in FIG. 4, for the wiring board laminate 1 of this structure, the first electrical inspection probe 201a is brought into contact with the first electrode 41a or the second electrode 42a, and the second electrical inspection probe 201b is brought into contact with the electrode 300 outside the board, and the capacitance C between the first wiring net 41 or the second wiring net 42 and the electrode 300 outside the board is measured, and the value of the obtained capacitance C is compared with a normal value C' previously obtained as knowledge to determine whether the wiring is good or bad. In an actual wiring board, the number of wiring nets is much greater, but with this method, it is possible to inspect all electrically connected wiring nets at once, and further, it is possible to inspect any electrode belonging to any of the nets by applying the probe to it. Therefore, in a wiring board laminate with a large number of wiring nets, the number of inspection points can be reduced, and the electrical inspection can be performed more efficiently. This makes it possible to shorten the tact time.

[0031] In the wiring board laminate 1 configured as described above, capacitance C occurs between the first wiring net 41, the second wiring net 42, the conductive layer 101, and the external electrode 300 outside the substrate. Since the first wiring net 41, the second wiring net 41, and the conductive layer 101 electrically connected together, and the external electrode 300 outside the substrate are each considered to be capacitor electrodes, the value of this capacitance C changes if a short circuit or open circuit occurs anywhere in the first wiring net 41 or the second wiring net 42. In electrical testing using the capacitance method, this capacitance C is compared with the normal capacitance C', and the quality of the wiring net is determined based on the change. Therefore, in a conventional wiring board without a conductive layer 101, for example, if a break occurs at the end of the wiring net 41, the change in capacitance C is extremely small, making it difficult to determine whether the wiring net 41 is good or bad. By providing the first conductive layer 101, the wiring nets 41 and 42 serving as electrodes of the capacitor can be extended. Therefore, even if a break occurs at the end of the wiring net 41, for example, the capacitance C will change significantly compared to normal, making it possible to detect the break.

[0032] To inspect the third wiring net 43, as shown in Figure 4, the first electrical inspection probe 201a is brought into contact with the first electrode 41a or the second electrode 42a, and the second electrical inspection probe 201b is brought into contact with the third electrode 43a, and the third wiring net 43 is inspected as a capacitor composed of an electrode consisting of the first wiring net 41, the second wiring net 42, and the first conductive layer 101, and an electrode consisting of the third wiring net 43.If a break occurs, the capacitance C changes, making it possible to detect the break.

[0033] An electrical inspection is performed on the wiring board laminate 1 of the first embodiment using a known method. Specifically, as shown in Fig. 4, a first electrical inspection probe 201a is brought into contact with the third electrode 43a, a second electrical inspection probe 201b is brought into contact with an electrode 300 outside the substrate, and an AC voltage is applied to the third wiring net 43 and the external electrode 300 outside the substrate to measure the capacitance C. The obtained value of capacitance C is compared with a normal value to determine whether the wiring is good or bad.

[0034] An electrical inspection is performed on the wiring board laminate 1 of the first embodiment based on the technique of the present invention. Specifically, as shown in Fig. 3, a first electrical inspection probe 201a is brought into contact with the first electrode 41a or the second electrode 42a, and a second electrical inspection probe 201b is brought into contact with the third electrode 43a, and an AC voltage is applied to the electrode consisting of the first wiring net 41, the second wiring net 42, and the first conductive layer 101 and the electrode consisting of the third wiring net 43, and the capacitance C is measured. The obtained value of capacitance C is compared with a normal value to determine whether the wiring is good or bad.

[0035] (Second embodiment) [Structure of wiring board according to second embodiment] In electrical testing using the capacitance method, pass / fail is determined by comparing with a normal value, so large variations in capacitance C reduce the accuracy of the electrical testing. For example, the third wiring net 43 is made of fine wiring, so its area as a capacitor electrode is small, making it difficult to measure the capacitance. Furthermore, depending on the configuration, the distance between the electrodes may be large, making it difficult to measure the capacitance itself. Therefore, to improve the testing accuracy, a configuration that allows for a large area of ​​fine wiring in a short distance is required.

[0036] The structure of a wiring board laminate 1 according to a second embodiment that realizes this will be described below. FIG. 5 is a diagram illustrating the wiring board laminate 1 of this embodiment. As shown in FIG. 5, the wiring board laminate 1 includes a wiring board 40 and a first conductive layer 101. The wiring board 40 includes a first wiring net 41 electrically connected by the first conductive layer 101, a second wiring net 42 electrically connected by the first conductive layer 101, and a third wiring net 43 electrically connected by the first conductive layer 101. a third wiring net 43 electrically insulated from all of the first conductive layer 101, the first wiring net 41, and the second wiring net 42; and a third wiring net 43 electrically insulated from all of the first, second, and third wiring nets and the first conductive layer, with a portion of the third wiring net being connected to an electrode 44a. and an electrode layer 44 exposed to the outside of the substrate.

[0037] In FIG. 5, the internal electrode portion 44b of the electrode layer 44 and the electrode 44a of the electrode layer 44 appear to be disconnected, but in the actual substrate, they are electrically connected.

[0038] In this structure, the third electrode net 43 and the electrode layer 44 face each other via the insulating resin layer 45, and since the facing area is large and the distance between the electrodes is small, the resulting capacitance C can be increased, the rate of variation in capacitance C is reduced, and high-precision electrical testing can be achieved.

[0039] Although the method for increasing the capacitance C is not limited to this, it is preferable to shorten the distance between the third wiring net 43 and the electrode layer 44. If the single layer or laminated insulating resin layer 45 separating them becomes a thick film of 100 μm or more, the accuracy of the dielectric measurement decreases and problems occur in the inspection, so it is desirable that the thickness of the insulating resin layer 45 be 100 μm or less.

[0040] An electrical inspection is performed on the wiring board laminate 1 of the second embodiment. Specifically, as shown in Fig. 5, a first electrical inspection probe 201a is brought into contact with the third electrode 43a, and a second electrical inspection probe 201b is brought into contact with the electrode 44a that is continuous with the internal electrode portion 44b and exposed to the outside, and an AC voltage is applied between the third electrode net 43 and the electrode layer 44 to measure the capacitance C. The obtained value of capacitance C is compared with a normal value to determine whether the wiring is good or bad.

[0041] To inspect the third wiring net 43, as shown in Figure 6, the first electrical inspection probe 201a is brought into contact with the first electrode 41a or the second electrode 42a, and the second electrical inspection probe 201b is brought into contact with the third electrode 43a, and the third wiring net 43 is inspected as a capacitor consisting of an electrode made up of the first wiring net 41, the second wiring net 42, and the first conductive layer 101, and an electrode made up of the third wiring net 43.If a break occurs, the capacitance C changes, making it possible to detect the break.

[0042] According to the wiring board laminate of the present invention, it is possible to perform capacitance electrical testing of a wiring board having a support with high precision. [Industrial Applicability]

[0043] The present invention can be used for a wiring substrate laminate used in the manufacture of a semiconductor device. [Explanation of symbols]

[0044] 1. Wiring board laminate 40... Wiring board 41...First wiring net 41a... First electrode 41b...First wiring 41c: First through electrode 42...Second wiring net 42a... Second electrode 42b...Second wiring 42c...Second through electrode 43...Third wiring net 43a...Third electrode 43b...Third wiring 43c...Third through electrode 44...electrode layer 44a... Electrode of electrode layer 44b: Internal electrode portion of electrode layer 45 Insulating resin layer 101: First conductive layer 104...Support 201a··First electrical testing probe 201b Second electrical testing probe 300... Electrode outside the substrate

Claims

1. A support; a first conductive layer provided on an upper surface of the support; a wiring substrate provided on an upper surface of the first conductive layer; Equipped with When a wiring net is referred to as a continuum of conductors including wiring arranged on each layer of a wiring board, electrodes of the wiring exposed to the outside of the board for connection to the outside, and through electrodes for connecting the wiring of each layer, The wiring board is a first wiring net having an electrode exposed on at least one surface of the wiring substrate and electrically connected to the first conductive layer; a second wiring net having an electrode exposed on at least one surface of the wiring substrate, electrically connected to the first conductive layer, and electrically connected to the first wiring net only through the first conductive layer; an electrode exposed only on one side of the wiring substrate, and a third wiring net electrically insulated from the first conductive layer and the first and second wiring nets by an insulating resin layer; Equipped with the first and second wiring nets are exposed on both sides of the wiring board, the electrodes of the first, second, and third wiring nets exposed on one surface of the wiring substrate are for electrically connecting to electronic components; The wiring board laminate is characterized in that the wiring board has a fine wiring portion as a part of a rewiring layer, and is formed independently from other wiring portions of the rewiring layer.

2. A support; a first conductive layer provided on an upper surface of the support; a wiring substrate provided on an upper surface of the first conductive layer; Equipped with When a wiring net is referred to as a continuum of conductors including wiring arranged on each layer of a wiring board, electrodes of the wiring exposed to the outside of the board for connection to the outside, and through electrodes for connecting the wiring of each layer, The wiring board is a first wiring net having an electrode exposed on at least one surface of the wiring substrate and electrically connected to the first conductive layer; a second wiring net having an electrode exposed on at least one surface of the wiring substrate, electrically connected to the first conductive layer, and electrically connected to the first wiring net only through the first conductive layer; a third wiring net having an electrode exposed only on one side of the wiring substrate and electrically insulated from the first conductive layer and the first and second wiring nets by an insulating resin layer; an electrode layer that is electrically insulated from the first conductive layer and the first, second, and third wiring nets and has a portion thereof exposed to the outside of the wiring substrate; Equipped with the first and second wiring nets are exposed on both sides of the wiring board, the electrodes of the first, second, and third wiring nets exposed on one surface of the wiring substrate are for electrically connecting to electronic components; The wiring board laminate is characterized in that the wiring board has a fine wiring portion as a part of a rewiring layer, and is formed independently from other wiring portions of the rewiring layer.

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