Electronic component and production method thereof

Abstract

To provide a convenient production method of an electronic component when producing the electronic component having different substrate materials.SOLUTION: A production method of an electronic component of the present invention includes a preparation step, a plasma treatment step, a deposition step, and an electrode formation step. In the preparation step, an electrode formation body is prepared, comprising a conductive substrate and a resin that is laminated on the surface of the substrate with a through hole formed in the thickness direction. In the plasma treatment step, ions are implanted into the inner surface of the through hole by applying a plasma treatment to the resin to give conductivity to the surface layer part of the inner surface. In the deposition step, a solid body in which first metal ions are reduced is deposited on the inner surface by electrifying the surface layer part, after the electrode formation body is immersed in a plating solution including first and second metal ions. In the electrode formation step, a concave electrode is formed by applying a metal plating, in which the second metal ions are reduced, to a surface exposed from the through hole on the surface of the substrate and to the inner surface, by electrifying the substrate and the solid body.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to an electronic component having a concave electrode and a method for manufacturing the same. [Background technology]

[0002] Conventionally, an electronic component of this type is known, for example, from Patent Document 1. The electronic component described in Patent Document 1 includes an IC chip, a pad electrode, a substrate, and a protruding electrode. The pad electrode is provided on the surface of the IC chip. The pad electrode is covered with a substrate (underlying metal layer) containing metal. The protruding electrode protrudes from a portion of the substrate that covers the pad electrode. A recess (depression) surrounded by the side edges of the protruding electrode is formed on the top surface of the protruding electrode.

[0003] The protruding electrodes are formed by metal plating. In one example of a method for forming the protruding electrodes, first, the surface of the pad electrode and the surface of the IC chip are covered with a substrate. Next, the substrate is covered with a plating resist. Through holes corresponding to the portions where the protruding electrodes will be formed are formed in the plating resist. Next, the substrate exposed through the through holes is dry-etched. During this process, some of the metal constituting the substrate is scattered and adheres to the inner surfaces of the through holes by the dry etching. Next, plating constituting the protruding electrodes is applied to the substrate exposed through the through holes and to the inner surfaces of the through holes. The plating grows from the metal adhered to the substrate exposed through the through holes and to the inner surfaces of the through holes. Finally, the plating resist and the portions of the substrate not located between the pad electrode and the protruding electrode are removed. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 3-232233 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the method for manufacturing electronic components described in Patent Document 1, dry etching is required to scatter a portion of the metal constituting the substrate onto the inner surface of the through hole while leaving the substrate at the bottom of the through hole. The etching method and etching conditions for achieving this condition depend heavily on the substrate material. In other words, the etching method and conditions must be considered for each substrate material. As such, there is still room for improvement in the method for manufacturing electronic components from the perspective of convenience in manufacturing electronic components with different substrate materials.

[0006] SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned problems and to provide a method for manufacturing electronic components that is highly convenient when manufacturing electronic components having different substrate materials. [Means for solving the problem]

[0007] In order to achieve the above object, the method for manufacturing an electronic component according to the present invention comprises: a preparation step of preparing an electrode formation body including a conductive base material and a resin layered on a surface of the base material and having through holes formed therein in a thickness direction; a plasma treatment step of subjecting the resin to plasma treatment to inject ions into the inner surface of the through hole, thereby imparting electrical conductivity to a surface layer portion of the inner surface; a deposition step of immersing the electrode formation body in a plating solution containing first metal ions and second metal ions, and then applying current to the surface layer portion to deposit a solid body in which the first metal ions are reduced on the inner surface; an electrode formation step in which a metal plating in which the second metal ions are reduced is applied to the exposed surface of the surface of the base material exposed from the through hole and the inner surface by passing a current through the base material and the solid body, thereby forming a concave electrode; Includes: [Effects of the Invention]

[0008] According to the present invention, convenience is improved when manufacturing electronic components having different substrate materials. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a perspective view showing an electronic component manufactured by a method for manufacturing an electronic component according to an embodiment of the present invention; [Figure 2] FIG. 2 is an enlarged cross-sectional view of a concave electrode taken along line II-II in FIG. [Figure 3] 3 is a flowchart showing a method for manufacturing an electronic component according to an embodiment of the present invention. [Figure 4] 5A to 5C are enlarged cross-sectional views illustrating a method for manufacturing an electronic component according to an embodiment of the present invention. [Figure 5] FIG. 5 is an enlarged cross-sectional view showing a step subsequent to FIG. 4. [Figure 6] FIG. 6 is an enlarged cross-sectional view showing a step subsequent to FIG. 5. [Figure 7] FIG. 7 is an enlarged cross-sectional view showing a step subsequent to FIG. 6. [Figure 8] FIG. 8 is an enlarged cross-sectional view showing a step subsequent to FIG. 7. [Figure 9] FIG. 2 is a diagram showing an electron microscope image of a first sample in a manufacturing method of an electronic component according to an embodiment of the present invention. [Figure 10] 10 is a graph showing the analysis results at position P1 in FIG. 9. [Figure 11] 10 is a graph showing the analysis results at position P2 in FIG. 9. [Figure 12] 10 is a graph showing the analysis results at position P3 in FIG. 9. [Figure 13] FIG. 4 is a diagram showing an electron microscope image of a second sample in the method for manufacturing an electronic component according to the embodiment of the present invention. [Figure 14] 14 is a graph showing the analysis results at position P11 in FIG. 13. [Figure 15] 14 is a graph showing the analysis results at position P12 in FIG. 13. [Figure 16] 14 is a graph showing the analysis results at position P13 in FIG. 13. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the present invention is not limited to this embodiment. Furthermore, in the drawings, substantially the same components are designated by the same reference numerals and description thereof will be omitted.

[0011] In the following, for the sake of convenience, terms indicating directions such as "upper," "lower," and "side" are used, but these terms do not limit the manufacturing state, use state, etc. of the electronic component according to the present invention.

[0012] In this specification and claims, the term "major component" refers to the component that is the largest in weight or volume among the components that make up a constituent element. When a constituent element is composed of one type of component, the term "major component" refers to that one type of component.

[0013] <Embodiment> Fig. 1 is a perspective view showing an electronic component manufactured by a method for manufacturing an electronic component according to an embodiment of the present invention, Fig. 2 is an enlarged cross-sectional view of a concave electrode taken along line II-II in Fig. 1.

[0014] As shown in FIG. 1, the electronic component 1 includes a main body 10, a substrate 20, and a concave electrode 30. For example, the electronic component 1 is a discrete component or a module. For example, the main body 10 is a ceramic laminate having multiple insulating layers formed of ceramic and conductors disposed between the laminated insulating layers. In this embodiment, the concave electrode 30 has a rectangular parallelepiped outer shape. In the example shown in FIG. 1, one substrate 20 and one concave electrode 30 are provided, but two or more of each may be provided.

[0015] 2, a pad electrode 11 is provided on the surface 10a of the main body 10. The pad electrode 11 is electrically connected to a conductor disposed on the surface 10a of the main body 10 or to a conductor disposed inside the main body 10. When the main body 10 is a ceramic laminate, the pad electrode 11 is formed by applying a conductive paste containing a metal such as copper to the surface 10a and co-firing it with the main body 10.

[0016] A substrate 20 is laminated on the pad electrode 11. The substrate 20 is conductive and electrically connected to the pad electrode 11. The substrate 20 is mainly composed of metal. For example, the substrate 20 is a metal film mainly composed of aluminum, titanium, chromium, nickel, copper, silver, platinum, gold, or an alloy thereof. In this embodiment, the substrate 20 is mainly composed of palladium.

[0017] A concave electrode 30 is provided on the upper surface 20a of the substrate 20, which is opposite to the surface 20c facing the pad electrode 11. The concave electrode 30 is electrically connected to the pad electrode 11 via the substrate 20. The concave electrode 30 is mainly composed of metal. In this embodiment, the concave electrode 30 is mainly composed of gold.

[0018] The concave electrode 30 has a facing surface 30a facing the upper surface 20a of the substrate 20, a top surface 30b opposite the facing surface 30a, and an outer electrode surface 30c connecting the facing surface 30a and the top surface 30b. The outer electrode surface 30c corresponds to the outer surface in the present invention. A recess 31 recessed toward the substrate 20 along the thickness direction of the substrate 20 (hereinafter simply referred to as the thickness direction) is formed on the top surface 30b. In this embodiment, the recess 31 has a rectangular parallelepiped shape (see FIG. 1). The recess 31 has a bottom surface 31a and an inner peripheral surface 31b. The bottom surface 31a and the inner peripheral surface 31b form the inner surface 31c of the recess 31. The recess 31 can function as a connection portion for connecting the electronic component 1 to another electronic component, a substrate, or the like. For example, a terminal of the other electronic component or a wire connected to the terminal is connected to the recess 31. More specifically, the terminal or wire is inserted into the internal space of the recess 31 and electrically connected to the bottom surface 31a and the inner peripheral surface 31b via a die bond material disposed in the internal space. Such a die bond material may be heated and melted to electrically connect the recess 31 and the terminal or wire.

[0019] A solid body 40 is formed in the concave electrode 30. The solid body 40 has an outer solid body 41, an inner solid body 42, and an inner solid body 43. The outer solid body 41 is formed on the outer peripheral surface 30c of the electrode. The inner solid body 42 is formed on the inner peripheral surface 31b. The inner solid body 43 is formed on the upper surface 20a of the substrate 20. The solid body 40 may be formed on the bottom surface 31a.

[0020] The metal that is the main component of the solid body 40 can form a complex and is different from the metal that is the main component of the substrate 20 and the metal that is the main component of the concave electrode 30. In this embodiment, the main component of the solid body 40 is sodium.

[0021] In the example shown in FIG. 2 , the solid bodies 40 are formed on a portion of each of the outer peripheral surface 30c, inner peripheral surface 31b, and upper surface 20a of the electrode. Note that the number of solid bodies 40 and the position, size, and shape of each solid body 40 are not limited to those shown in FIG. 2 . For example, the solid bodies 40 may be formed on the entire surface of each of the outer peripheral surface 30c, inner peripheral surface 31b, and upper surface 20a of the electrode. Also, in the example shown in FIG. 2 , the outer solid body 41 is arranged so as to be embedded in the concave electrode 30, but this is not limiting. For example, the outer solid body 41 may be formed on a flat or approximately flat outer peripheral surface 30c of the electrode. Meanwhile, the inner solid body 42 and the inner solid body 43 are each formed on the flat inner peripheral surface 31b or upper surface 20a, but may be formed so as to be embedded in the concave electrode 30 or the substrate 20.

[0022] The ratio of the area of the outer solid body 41 to the area of the region of the outer electrode surface 30c exposed from the outer solid body 41 is greater than the ratio of the area of the inner solid body 42 to the area of the inner electrode surface 31b exposed from the inner solid body 42. For example, when the concave electrode 30 is viewed from the outside, the ratio of the area of the outer solid body 41 to the area of the outer electrode surface 30c is greater than the ratio of the area of the inner solid body 42 to the area of the inner electrode surface 31b.

[0023] In the electronic component according to this embodiment, an alloy is formed between the gold constituting the concave electrode 30 and the sodium constituting the solid body 40 at the contact portion of the concave electrode 30 with the solid body 40. Because this alloy is harder than gold alone, the concave electrode 30 is less likely to be deformed or damaged compared to a concave electrode without the solid body 40. Therefore, malfunction of the electronic component 1 caused by deformation or damage to the concave electrode 30 can be suppressed.

[0024] In the electronic component according to this embodiment, the ratio of the area of the outer solid body 41 exposed from the outer solid body 41 to the area of the inner solid body 42 exposed from the outer solid body 41 is greater than the ratio of the area of the inner solid body 42 exposed from the inner solid body 42 to the area of the outer solid body 41 exposed from the inner solid body 42. Furthermore, the linear expansion coefficient of sodium, the main component of the solid body 40, is greater than the linear expansion coefficient of gold, the main component of the concave electrode 30. As a result, when the concave electrode 30 is heated, the outer solid body 41 expands more than the inner solid body 42. In other words, the wall portion constituting the inner solid body 31b of the concave electrode 30 deforms, bending toward the internal space of the recess 31. This reduces the opening area of the recess 31, thereby reducing the likelihood that the die bond material disposed in the internal space of the recess 31 will leak out of the recess 31. This improves the reliability of the electrical connection between the electronic component 1 and other electronic components or substrates.

[0025] <Electronic component manufacturing method> Next, an example of a method for manufacturing an electronic component according to the present invention will be described with reference to Fig. 3 to Fig. 8. Fig. 3 is a flowchart showing a method for manufacturing an electronic component according to an embodiment of the present invention. Fig. 4 is an enlarged cross-sectional view corresponding to Fig. 2 of the method for manufacturing an electronic component according to an embodiment of the present invention. Figs. 5 to 8 are enlarged cross-sectional views showing each step in the method for manufacturing an electronic component according to an embodiment of the present invention.

[0026] (preparation process) First, in step S1, a main body 10 having a pad electrode 11 and a substrate 20 is prepared, as shown in Fig. 4. In this embodiment, the substrate 20 is disposed across the surface of the pad electrode 11 and the surface 10a of the main body 10, but it may be disposed only on the surface of the pad electrode 11. In this embodiment, the preparation process includes a photoexposure process and a development process, which will be described below.

[0027] (Photosensitization process) Next, in step S2, resin 50 is laminated on substrate 20. Resin 50 has an upper surface 50a opposite to the surface facing substrate 20. For example, resin 50 contains an organic compound such as polyimide, polyparaphenylene benzobisoxazol (PBO), phenol, acrylic acid ester, or sodium caseinate. In this embodiment, resin 50 is a negative dry resist film that is cured by exposure to light. Resin 50 has hole forming portions 52 in which through holes 51, which will be described later, are formed.

[0028] As shown by the arrows in FIG. 4, light that exposes the resin 50 is irradiated onto the portion of the resin 50 excluding the hole formation portion 52. For example, the light is irradiated while a mask that covers only the hole formation portion 52 is placed on the upper surface 50a of the resin 50. The exposed portion of the resin 50 hardens and becomes insoluble in the developer. On the other hand, the unexposed portion of the resin 50 is soluble in the developer.

[0029] (Developing process) Next, in step S3, as shown in FIG. 5, the resin 50 is exposed to a developer, whereby the hole formation portion 52 is dissolved and removed by the developer. As a result, a through hole 51 is formed in the resin 50. For example, the developer is an alkaline developer. In this embodiment, the through hole 51 has a rectangular parallelepiped shape. The through hole 51 has an inner surface 51a. The substrate 20 has an exposed surface 20b that is exposed to the outside of the resin 50 from the through hole 51.

[0030] Residues 53 of the resin 50 that should be removed in the development process remain in the through-hole 51. In the example shown in Fig. 5, the residues 53 remain in the corners formed by the inner surface 51a and the exposed surface 20b, but may also remain in other parts of the through-hole 51.

[0031] The electrode formation body 100 is formed by the preparation process including the above-described steps S1 to S3. In the example of the manufacturing method shown in FIG. 3, the preparation process includes, but is not limited to, a photoexposure process shown in step S2 and a development process shown in step S3. In the preparation process, it is sufficient that the electrode formation body 100 is formed by laminating the resin 50, in which the through holes 51 are formed, on the substrate 20. For example, a resin film in which the through holes 51 are formed in advance may be laminated on the substrate 20. Furthermore, the resin 50 is not limited to a negative dry resist film, and may be, for example, a positive photoresist that is applied to the upper surface 20a of the substrate 20 (see FIG. 5). In this case, the hole formation portion 52 is exposed to light and becomes soluble in the developer.

[0032] (Plasma treatment process) Next, in step S4, as shown in FIG. 6, ions 60 generated by the plasma treatment are implanted into the surface layer 54 of the inner surface 51a, thereby imparting conductivity to the surface layer 54. For example, a parallel plate plasma device (RPLA-10 manufactured by SUMCO) is used for the plasma treatment.

[0033] In this embodiment, oxygen plasma treatment is performed using oxygen gas as a reactive gas. In the oxygen plasma treatment, oxygen radicals, oxygen ions, and electrons are generated from the oxygen gas. At least some of the oxygen ions are implanted into the surface layer 54 through the inner surface 51a. The oxygen radicals bond with carbon atoms and hydrogen atoms constituting the residue 53 (see FIG. 5 ) to form carbon dioxide or water. This volatilizes and removes the residue 53. In other words, the plasma treatment process also serves as a descum treatment for removing the residue 53 by plasma ashing. Note that, as shown in FIG. 6 , ions 60 may be implanted not only into the inner surface 51a but also into the surface layer of a surface other than the inner surface 51a, for example, into the surface layer 55 of the upper surface 50a.

[0034] (Precipitation process) Next, in step S5, while the electrode formation body 100 is immersed in the plating solution, a current is passed through at least the surface layer portion 54. In this embodiment, the pad electrode 11 is electrically connected to the negative electrode of a DC power supply (not shown). The positive electrode of the DC power supply is electrically connected to a plating electrode (not shown) that does not contact the electrode formation body 100 but contacts the plating solution. The current applied to the pad electrode 11 flows through the substrate 20 and the conductive surface layer portion 54. Therefore, the substrate 20 and the surface layer portion 54 function as an anode, while the plating electrode functions as a cathode. This causes a current to flow through the plating solution located between the anode and the cathode.

[0035] In this embodiment, the plating solution is an aqueous solution of sodium gold sulfite (Na3Au(SO3)2), and sodium ions (Na + ) and gold ions (Au + ) The sodium ions correspond to the first metal ions in this invention. The gold ions correspond to the second metal ions in this invention. When electricity is passed through the plating solution, gold electroplating occurs through a multi-step reaction shown in the reaction formula below.

[0036] [ka]

[0037] 7, when the concentration of sodium ions in the plating solution is high, an outer solid body 41 is deposited on the inner surface 51a at the beginning of current application during electroplating. The outer solid body 41 is a solid body of sodium produced by the reduction of sodium ions in the plating solution. The outer solid body 41 is formed in contact with the inner surface 51a, and is therefore electrically connected to the surface layer portion 54.

[0038] In the plating solution at the start of energization, the ratio of the mass concentration of sodium (g / L) to the mass concentration of gold (g / L) is preferably 3.0 or more, and particularly preferably 3.4 or more. Such a plating solution has a high sodium ion concentration, which allows the outer surface solid body 41 to be more reliably deposited.

[0039] In the deposition step, an internal solid body 43 may be deposited on the exposed surface 20b. Similar to the external solid body 41, the internal solid body 43 is a solid body of sodium formed by the reduction of sodium ions in the plating solution. Furthermore, a gold plating 70 formed by the reduction of gold ions in the plating solution may be deposited on the exposed surface 20b. The gold plating 70 is an example of the metal plating of the present invention.

[0040] (Electrode formation process) Next, in step S6, a current is passed through the substrate 20 and the outer solid body 41. In this embodiment, continuing from the deposition step, a current is passed through the pad electrode 11. The current flows through the substrate 20 and the surface layer 54, and then flows from at least one of the substrate 20 and the surface layer 54 to the outer solid body 41. At this time, the outer solid body 41 is electrically connected to the surface layer 54, and therefore can function as an anode.

[0041] When a current is applied to the substrate 20 and the outer solid body 41, as shown in FIG. 8, gold ions in the plating solution are reduced and gold plating 70 is deposited on the exposed surface 20b and the inner surface 51a. This forms a concave electrode 30 including the gold plating 70. The gold plating 70 grows from each of the exposed surface 20b and the inner surface 51a. Specifically, the gold plating 70 grows from the exposed surface 20b along the depth direction of the through hole 51 (hereinafter simply referred to as the depth direction). In this embodiment, the depth direction of the through hole 51 coincides with the thickness direction of the substrate 20. Furthermore, the gold plating 70 grows from the inner surface 51a toward the center of the through hole 51 as viewed along the depth direction.

[0042] The gold plating 70 grows in different directions from the exposed surface 20b and the inner surface 51a, thereby forming the recess 31. In this embodiment, since the through-hole 51 has a rectangular parallelepiped shape, the recessed electrode 30 and the recess 31 are also formed in a rectangular parallelepiped shape. As shown in FIG. 8, an inner solid body 42 may be formed on the inner peripheral surface 31b. In addition, a solid body 40 (not shown) may be formed on the bottom surface 31a.

[0043] (Removal process) Next, in step S7, the resin 50 including the surface layers 54, 55 and the portions of the base material 20 that do not overlap with the concave electrode 30 when viewed in the thickness direction are removed. For example, the resin 50 can be removed by immersing the electrode formation body 100 in a remover. The base material 20 can be partially removed by, for example, etching.

[0044] According to the manufacturing method of this embodiment, by applying current to the surface layer 54, which has been made conductive by the implantation of ions 60, an outer solid body 41 formed by the reduction of first metal ions can be deposited on the inner surface 51a of the through-hole 51. Furthermore, a gold plating 70 formed by the reduction of second metal ions can be grown from the outer solid body 41. In other words, the concave electrode 30 can be formed without dry etching, the etching method and etching conditions of which (e.g., power output and gas pressure in plasma processing) are highly dependent on the material of the substrate 20. Therefore, compared to the conventional technique, this method is more convenient when manufacturing electronic components 1 whose substrate 20 is made of different materials.

[0045] When through-hole 51 is formed in resin 50, a portion of resin 50 that should be removed may remain inside through-hole 51 as residue 53. Residue 53 may be mixed into gold plating 70 during the electrode formation process and may deteriorate the properties of gold plating 70, such as adhesion and conductivity. On the other hand, according to the above-described manufacturing method, residue 53 is removed by plasma treatment, so deterioration of the properties of gold plating 70 can be suppressed.

[0046] Furthermore, according to the manufacturing method of this embodiment, in the plasma treatment step, the implantation of ions 60 into surface layer portion 54 and the removal of residue 53 can be performed simultaneously. Therefore, the number of steps in manufacturing electronic component 1 can be reduced compared to a method in which the implantation of ions 60 and the removal of residue 53 are performed by different methods and steps.

[0047] Furthermore, according to the manufacturing method of this embodiment, oxygen plasma treatment is performed, which allows oxygen ions to be implanted into inner surface 51a of through hole 51. At the same time, residue 53 can be removed by ashing. Therefore, the number of steps in manufacturing electronic component 1 can be reduced while suppressing deterioration of the characteristics of gold plating 70.

[0048] Plasma treatment using a gas containing an element highly reactive with metal (for example, tetrafluoromethane-oxygen gas containing highly reactive fluorine) may produce precipitates containing the highly reactive element. Such precipitates may deteriorate the properties of the gold plating 70 and may corrode the concave electrode 30. However, the manufacturing method described above uses oxygen gas in the plasma treatment, which reduces the possibility of the above-mentioned precipitates being produced. Therefore, deterioration of the properties and corrosion of the gold plating 70 can be suppressed.

[0049] Furthermore, according to the manufacturing method of this embodiment, the through holes 51 are formed after the resin 50 is laminated on the upper surface 20a of the base material 20, and therefore, unlike a method in which the resin 50 with the through holes 51 formed in advance is laminated on the upper surface 20a of the base material 20, there is no need to align the resin 50 on the upper surface 20a of the base material 20. Therefore, no device or technique for aligning the resin 50 is required, and therefore, laminating the resin 50 on the upper surface 20a of the base material 20 becomes easier.

[0050] <Example> The first and second samples of the concave electrode 30 fabricated according to the above method were observed using a scanning electron microscope (SEM) and subjected to qualitative and quantitative elemental analysis using energy dispersive X-ray spectroscopy (EDX). In the fabrication of the first sample, current was applied for only 30 seconds during the deposition and electrode formation processes. In the fabrication of the second sample, current was applied for 20 minutes until the formation of the concave electrode 30 was complete. In the second sample, in order to observe the cross section of the recess 31, the concave electrode 30 was cut at a position corresponding to line XIII-XIII in FIG. 8 , and the piece with the substrate 20 was used for observation and analysis. The first and second samples were not subjected to the removal process.

[0051] For SEM observation, a JEOL Ltd. scanning electron microscope JSM-7900 was used. The observation conditions were high vacuum mode, a working distance of 10 mm, an accelerating voltage of 10 kV, and SE observation mode. For EDX, an Oxford Instruments EMAX energy dispersive X-ray analyzer was used. The vacuum conditions, working distance, and accelerating voltage for EDX analysis were the same as those for the observation conditions described above.

[0052] Fig. 9 is a diagram showing an oblique electron microscope image of the inner surface 51a of the first sample. Figs. 10 to 12 are graphs showing the EDX analysis results at positions P1 to P3 in Fig. 9. Fig. 9 shows the exposed surface 20b of the substrate 20, the upper surface 50a of the resin 50, and the inner surface 51a of the through hole 51 that appears between them.

[0053] At position P1 corresponding to exposed surface 20b, gold (Au) was detected in addition to palladium (Pd), the main component of substrate 20, as shown in FIG. 10. This suggests that gold plating 70 was deposited on exposed surface 20b in the first sample to which current was applied for 30 seconds. At position P2 (see FIG. 9), corresponding to an upper portion of inner surface 51a near top surface 50a, carbon (C) and oxygen (O), which constitute resin 50, were detected, as shown in FIG. 11. At position P3 (see FIG. 9), corresponding to a lower portion of inner surface 51a near exposed surface 20b, sodium (Na) was detected in addition to carbon and oxygen, as shown in FIG. 12. This suggests that outer surface solids 41 containing sodium were deposited on a portion of inner surface 51a.

[0054] Fig. 13 is an enlarged view showing an electron microscope image of a cut surface of the second sample. Figs. 14 to 16 are graphs showing the analysis results at positions P11 to P13 in Fig. 13. In Fig. 13, resin 50, gold plating 70, and outer surface solid body 41 formed on inner surface 51a can be seen.

[0055] At position P11 corresponding to resin 50, carbon and oxygen constituting resin 50 were detected as shown in Fig. 14. At position P12 (see Fig. 13) corresponding to gold plating 70, gold (Au) was detected as shown in Fig. 15. At position P13 (see Fig. 13) corresponding to inner surface 51a, sodium (Na) was detected in addition to carbon and oxygen constituting resin 50 and gold constituting gold plating 70 as shown in Fig. 16.

[0056] In this example, from the observation and analysis of the first and second samples, it is believed that the outer surface solid body 41 is deposited on the inner surface 51a in the early stage of energization, and then the gold plating 70 is deposited.

[0057] The present invention is not limited to the above-described embodiment and can be embodied in various other forms. For example, although the through-hole 51 has a rectangular parallelepiped shape in the above description, the present invention is not limited to this. For example, the through-hole 51 may be formed in a cylindrical shape. In this case, the gold plating 70 grows from both the exposed surface 20b and the inner surface 51a, so the concave electrode 30 and the recess 31 can also be formed in a cylindrical shape.

[0058] In addition, in the above description, the first metal ion is a sodium ion and the second metal ion is a gold ion, but the present invention is not limited to this.

[0059] Although the present invention has been fully described in connection with the preferred embodiment with reference to the accompanying drawings, various changes and modifications will become apparent to those skilled in the art, and it is to be understood that such changes and modifications are included within the scope of the present invention as defined by the appended claims unless they depart therefrom.

[0060] The above explanation can also be expressed as follows.

[0061] The method for manufacturing an electronic component according to the first aspect includes: a preparation step of preparing an electrode formation body including a conductive base material and a resin layered on a surface of the base material and having through holes formed therein in a thickness direction; a plasma treatment step of subjecting the resin to plasma treatment to inject ions into the inner surface of the through hole, thereby imparting electrical conductivity to a surface layer portion of the inner surface; a deposition step of immersing the electrode formation body in a plating solution containing first metal ions and second metal ions, and then applying current to the surface layer portion to deposit a solid body in which the first metal ions are reduced on the inner surface; an electrode formation step in which a metal plating in which the second metal ions are reduced is applied to the exposed surface of the surface of the base material exposed from the through hole and the inner surface by passing a current through the base material and the solid body, thereby forming a concave electrode; Includes:

[0062] The manufacturing method of the second embodiment is In the manufacturing method of the first embodiment, The plasma treatment removes the resin residue remaining in the through-holes.

[0063] The manufacturing method of the third embodiment is In a second aspect, the plasma treatment is an oxygen plasma treatment, The ions implanted into the inner surface are oxygen ions.

[0064] The manufacturing method of the fourth embodiment is In any one of the manufacturing methods of the first to third aspects, the resin is a photoresist that is hardened by exposure to light or a photoresist that is soluble in a developer that dissolves the resin by exposure to light, The preparation step includes: a photoexposure step of exposing a hole formation portion where the through hole is to be formed or a portion excluding the hole formation portion of the resin laminated on the surface of the base material to light that exposes the resin; a developing step of dissolving the hole forming portion with the developer to form the through hole; Includes:

[0065] The manufacturing method of the fifth embodiment is In the manufacturing method of the first or second aspect, the first metal ion is a sodium ion; The second metal ion is a gold ion.

[0066] The electronic component of the sixth aspect is a substrate mainly composed of metal; a concave electrode that is disposed in contact with the substrate in a thickness direction of the substrate and that is mainly composed of metal; Equipped with a recess formed in the concave electrode from a surface opposite to a surface facing the substrate along the thickness direction so as to approach the substrate; A solid body capable of forming a complex and containing a metal different from the main component of the base material and the main component of the concave electrode is present on at least a portion of the outer circumferential surface of the concave electrode.

[0067] The electronic component of the seventh aspect is In the electronic component of the sixth aspect, the solid body has an outer solid body present on the outer peripheral surface of the concave electrode and an inner solid body disposed on the inner peripheral surface of the concave electrode, The ratio of the exposed area of the outer solid to the area of the region of the outer surface exposed from the outer solid is greater than the ratio of the exposed area of the inner solid to the area of the region of the inner surface exposed from the inner solid. [Industrial Applicability]

[0068] The method for manufacturing an electronic component according to the present invention is highly convenient when manufacturing electronic components having different substrate materials, and is therefore useful for manufacturing a variety of electronic components. [Explanation of symbols]

[0069] 1. Electronic Components 20 Base material 20a top surface 20b Exposed surface 30 concave electrode 30a Opposite side 30b top surface 30c Electrode outer surface 31 Recess 40 solids 41 External solid body 42 Inner solid body 50 resin 51 through hole 51a Inner surface 52 Hole forming part 53 Residue 54 Surface layer 60 ions 100 Electrode formation

Claims

1. a preparation step of preparing an electrode formation body including a conductive base material and a resin layered on a surface of the base material and having through holes formed therein in a thickness direction; a plasma treatment step of subjecting the resin to plasma treatment to inject ions into the inner surface of the through hole, thereby imparting electrical conductivity to a surface layer portion of the inner surface; a deposition step of immersing the electrode formation body in a plating solution containing first metal ions and second metal ions, and then applying current to the surface layer portion to deposit a solid body in which the first metal ions are reduced on the inner surface; an electrode formation step in which a metal plating in which the second metal ions are reduced is applied to the exposed surface of the base material exposed from the through hole and the inner surface by passing a current through the base material and the solid body, thereby forming a concave electrode; A method for manufacturing an electronic component, comprising:

2. The manufacturing method according to claim 1 , wherein the plasma treatment removes the resin residue remaining in the through-hole.

3. the plasma treatment is an oxygen plasma treatment, The ions implanted into the inner surface are oxygen ions. The method of claim 2.

4. the resin is a photoresist that is hardened by exposure to light or a photoresist that is soluble in a developer that dissolves the resin by exposure to light, The preparation step includes: a photoexposure step of exposing a hole formation portion where the through hole is to be formed or a portion excluding the hole formation portion of the resin laminated on the surface of the base material to light that exposes the resin; a developing step of dissolving the hole forming portion with the developer to form the through hole; Including, The manufacturing method according to any one of claims 1 to 3.

5. the first metal ion is a sodium ion; The second metal ion is a gold ion. The method according to claim 1 or 2.

6. a substrate mainly composed of metal; a concave electrode that is disposed in contact with the substrate in a thickness direction of the substrate and that is mainly composed of metal; Equipped with a recess formed in the concave electrode from a surface opposite to a surface facing the substrate along the thickness direction so as to approach the substrate; a solid body capable of forming a complex and containing a metal different from the main component of the base material and the main component of the concave electrode is present on at least a portion of the outer circumferential surface of the concave electrode; Electronic components.

7. the solid body has an outer solid body present on the outer peripheral surface of the concave electrode and an inner solid body disposed on the inner peripheral surface of the concave electrode, a ratio of an exposed area of the outer solid body to an area of the outer peripheral surface exposed from the outer solid body is greater than a ratio of an exposed area of the inner solid body to an area of the inner peripheral surface exposed from the inner solid body; The electronic component according to claim 6.

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