JP6237441B2 - Electrode structure, inspection jig, and manufacturing method of electrode structure - Google Patents

Description

  The present invention relates to an electrode structure in which electrodes are formed, an inspection jig using the electrode structure, and a method for manufacturing the electrode structure.

  Conventionally, the rear end of a contact that contacts the substrate to be inspected is brought into contact with the electrode, and the electrode and the inspection signal processing unit are connected by an electric wire, so that the contact is connected to the inspection signal processing unit. A substrate inspection jig that enables inspection is known (see, for example, Patent Document 1).

JP 2009-8516 A

  However, according to the above-described board inspection jig, there is a possibility that the rear end of the contact comes into contact with the electrode, the electrode is worn, and the electric wire is exposed.

  An object of the present invention is to provide an electrode structure that can easily reduce the risk of exposure of an electric wire due to wear of the electrode, an inspection jig using the electrode structure, and a method for manufacturing the electrode structure. .

  An electrode structure according to the present invention has a substantially flat surface, an insulating base material in which a through hole extending in a direction intersecting the surface is formed, and one end portion is inserted into the through hole, The tip of the one end portion is formed by an electric wire fixed to the through hole so that the through hole is located at a position deeper than the opening that opens in the surface, and the first metal having higher hardness than the electric wire. And an electrode formed with a plating.

  According to this configuration, the tip of the electric wire is located at a position deeper than the opening in the through hole, and the electrode is plated with the first metal having a hardness higher than that of the electric wire at the tip. Thereby, since plating is performed in the through-hole surrounded by the inner wall of the through-hole, it is easy to increase the electrode thickness. When the thickness of the electrode having higher hardness than that of the electric wire is increased, the possibility that the electrode is worn and the electric wire is exposed is reduced.

  The electrode is preferably substantially flush with the surface.

  According to this configuration, since the flat surface of the base material portion and the tip surface of the electrode are flush with each other, the positional accuracy in the height direction of the electrode is improved.

  Moreover, it is preferable that a surface plating layer made of a second metal is formed on the surface of the electrode.

  According to this configuration, since the electrode surface is coated with the surface plating layer, corrosion of the electrode is prevented.

  The first metal is preferably nickel, and the second metal is preferably gold.

  According to this structure, since an electrode is comprised with nickel whose hardness is higher than copper generally used as an electric wire material, abrasion of an electrode is reduced. In addition, since a gold surface plating layer is formed on the electrode surface, the effect of preventing corrosion of the electrode is high.

  An inspection jig according to the present invention guides one end of the probe to the above-described electrode structure, a probe having a wire shape, and an inspection point of a substrate to be inspected, and the other end of the probe A support for guiding the electrode structure to the electrode.

  According to this configuration, the other end of the probe contacts the electrode, and the electrode is worn. However, since the electrode is made of the first metal having higher hardness than the electric wire, the degree of wear is reduced. As a result, the possibility that the electrode is worn and the electric wire is exposed is reduced.

  Moreover, the manufacturing method of the electrode structure according to the present invention has a substantially flat surface, and the through hole is formed with respect to an insulating base material portion having a through hole extending in a direction intersecting the surface. An insertion step of inserting one end portion of the electric wire into the through hole from the opposite side of the opening portion that opens to the surface, and fixing the one end portion of the electric wire to the through hole; an end surface of the one end portion; and the base material portion A first processing step of processing the one end portion so that the surface of the first end portion is flush with the surface, and etching the one end portion from the opening side so that the tip of the one end portion is deeper than the opening portion. And a plating step of forming an electrode by plating the tip of the one end with a first metal having a hardness higher than that of the electric wire.

  According to this configuration, since the electrode structure described above can be manufactured, the thickness of the electrode having higher hardness than that of the electric wire is increased to reduce the possibility that the electrode is worn and the electric wire is exposed. Is easy.

  Moreover, it is preferable to further include a second processing step of processing the electrode substantially flush with the surface.

  According to this configuration, since the flat surface of the base material portion and the tip surface of the electrode are flush with each other, the positional accuracy in the height direction of the electrode is improved.

  Moreover, it is preferable to further include a surface plating step of forming a surface plating layer on the surface of the electrode by plating with a second metal.

  According to this configuration, since the electrode surface is coated with the surface plating layer, corrosion of the electrode is prevented.

  With the electrode structure, inspection jig, and electrode structure manufacturing method having such a configuration, it is easy to reduce the risk of exposure of the electric wire due to electrode wear.

It is a schematic longitudinal cross-sectional view which shows an example of the inspection jig provided with the electrode structure which concerns on one Embodiment of this invention, and has shown the state at the time of non-inspection. It is a schematic longitudinal cross-sectional view which shows the state at the time of the test | inspection of the inspection jig provided with the electrode structure shown in FIG. It is sectional drawing which shows an example of a structure of the electrode structure shown in FIG. It is explanatory drawing which shows an example of the manufacturing method of the electrode structure shown in FIG. It is explanatory drawing which shows an example of the manufacturing method of the electrode structure shown in FIG. It is explanatory drawing which shows the comparative example for demonstrating the effect of the electrode structure formed by the manufacturing method shown in FIG. 4, FIG. It is explanatory drawing which shows the comparative example for demonstrating the effect of the electrode structure formed by the manufacturing method shown in FIG. 4, FIG. It is explanatory drawing which shows the experimental result at the time of using the electrode structure shown in FIG. It is explanatory drawing which shows the experimental result at the time of using the electrode structure which concerns on the comparative example shown in FIG.

  Embodiments according to the present invention will be described below with reference to the drawings. In addition, the structure which attached | subjected the same code | symbol in each figure shows that it is the same structure, The description is abbreviate | omitted. FIG. 1 is a schematic longitudinal sectional view showing an example of an inspection jig 7 provided with an electrode structure 1 according to an embodiment of the present invention, and shows a state during non-inspection. FIG. 2 is a schematic longitudinal sectional view showing a state at the time of inspection of the inspection jig 7 provided with the electrode structure 1 shown in FIG.

  The inspection jig 7 includes a frame 7A as a base, an electrode structure 1 including a plurality of electrodes 2, a plurality of probes Pr, a support block E, an urging portion 10, and the like. Here, the support block E includes an inspection-side support E1 and an electrode-side support E2, and a connection member E3 that holds the inspection-side support E1 and the electrode-side support E2 in parallel at a predetermined distance.

  The probe Pr is formed of a tough metal such as tungsten (W), high-speed steel (SKH), beryllium copper (BeCu), or other conductor, and has a wire shape (flexible) that can be bent (flexible). It is formed in a rod shape. The diameter of the probe Pr is, for example, about 100 μm.

  The inspection-side support E1 has a plurality of unillustrated inspection guide holes that guide the tips of the plurality of probes Pr to inspection points provided on the wiring pattern of the substrate 100 to be inspected. The electrode side support E2 has a plurality of electrode guide holes (not shown) for guiding the rear end portions of the probes Pr to the plurality of electrodes 2. Each electrode 2 is connected to the board inspection apparatus by an electric wire 3. In this way, the front end portion of the conductive probe Pr comes into contact with the inspection point of the substrate 100, and the rear end portion of the probe Pr comes into contact with the electrode 2 connected to the substrate inspection device. 100 wiring patterns can be inspected. Although not shown, a surface plating layer 4 is formed on the surface of each electrode 2.

  As shown in FIG. 1 showing the state at the time of non-inspection and FIG. 2 showing the state at the time of inspection, the substrate 100 is disposed so as to abut on the facing surface F facing the substrate 100 of the support block E and supported by the substrate 100. When the block E is pressed, the support block E (the inspection-side support E1, the electrode-side support E2, and the connecting member E3) has an electrode structure against the urging force of the urging portions 10, 10,. Move relative to the body 1.

  Along with this, the rear end portion of the probe Pr is pushed relatively toward the front end portion by the electrode 2, so that the front end portion of the probe Pr tends to protrude from the facing surface F. Note that FIG. 2 shows a state in which the tip of the probe Pr protrudes from the facing surface F for ease of explanation.

  Due to the action of such a force, the tip of the probe Pr abuts against the inspection point of the substrate 100 and is held down, so the probe Pr that is in an inclined posture between the inspection-side support E1 and the electrode-side support E2. The intermediate portion of the wire will bend (bend). Therefore, because of the elastic restoring force of the probe Pr deformed in this way, the tip of the probe Pr contacts the inspection point with a predetermined contact pressure, and the rear end of the probe Pr contacts the electrode 2 with a predetermined contact pressure. The contact state between the probe tip and the inspection point and the contact state between the probe rear end and the electrode 2 are maintained.

  FIG. 3 is a cross-sectional view showing an example of the configuration of the electrode structure 1 shown in FIG. The electrode structure 1 shown in FIG. 3 has a substantially flat surface 11 that is disposed to face the electrode side support E2, and has an insulating property in which a through hole 12 that extends in a direction intersecting (orthogonal to) the surface 11 is formed. One end portion is inserted into the base material portion 13 and the through hole 12, and the tip 31 of the one end portion is inserted into the through hole 12 so that the through hole 12 is located deeper than the opening portion 14 that opens in the surface 11. An electric wire 3 made of copper (Cu) and an electrode 2 plated with nickel (Ni) (first metal) whose hardness is higher than that of the electric wire 3 are provided.

  The end surface of the electrode 2 is flush with the surface 11. The end face of the electrode 2 is plated with gold (Au) (second metal), and a surface plating layer 4 is formed on the end face of the electrode 2. The thickness of the electrode 2 is preferably as thick as 5 μm or more from the viewpoint of wear resistance, and a thickness of about 10 μm is suitable for practical use. The thickness of the surface plating layer 4 is, for example, 0.5 μm to 2 μm, and more preferably 1 μm. In each drawing, from the viewpoint of easy viewing of the drawing, the electric wire 3, the electrode 2, and the surface plating layer 4 may be hatched or omitted in cross section.

  As the electric wire 3, for example, a so-called magnet wire such as an enameled wire (a coated copper wire) can be used. The gap between the electric wire 3 and the through hole 12 is filled with the resin 5. The tip of the electric wire 3 is fixed to the through hole 12 by the resin 5.

  4 and 5 are explanatory views showing an example of a manufacturing method of the electrode structure 1 shown in FIG. First, in FIG. 4A, the electric wire 3 is inserted into the through hole 12 formed in the base material portion 13. Next, in FIG.4 (b), the curable resin hardened | cured with a heat | fever or light is filled into the clearance gap between the through-hole 12 and the electric wire 3, and it hardens | cures. Thereby, the electric wire 3 is fixed to the through hole 12. 4A and 4B correspond to an example of an insertion process.

  Next, in FIG.4 (c), the part which protrudes from the opening part 14 of the electric wire 3 is cut | disconnected, and the cross section, ie, the end surface of the front-end | tip 31, is grind | polished so that the surface 11 may become flush. FIG. 4C corresponds to an example of the first processing step.

  Next, in FIG. 5A, the copper tip 31 is etched by approximately 10 μm. FIG. 5A corresponds to an example of an etching process. In this case, since the etching is performed after the tip 31 is processed to be flush with the surface 11 in the first processing step of FIG. 4C, the recess depth of the tip 31 by the etching process is approximately 10 μm. , Machining accuracy is improved.

  Next, in FIG.5 (b), the nickel plating is given with respect to the front-end | tip 31 located in the position back from the surface 11, and the electrode 2 is formed. Nickel plating is performed until the tip of the electrode 2 protrudes from the opening 14. FIG. 5B corresponds to an example of a plating process. As the plating method, for example, a brush plating method can be used.

  Next, in FIG. 5C, the electrode 2 is polished until the tip of the electrode 2 is flush with the surface 11. FIG. 5C corresponds to an example of the second processing step. Next, in FIG.5 (d), the front-end | tip of the electrode 2 is gold-plated and the surface plating layer 4 is formed. FIG. 5D corresponds to an example of a surface plating process. As described above, the electrode structure 1 shown in FIG. 3 is formed by the manufacturing method shown in FIGS. 4 (a) to 5 (d).

  6 and 7 are explanatory views showing comparative examples for explaining the effect of the electrode structure 1 formed by the manufacturing method shown in FIGS. 4 and 5. 6 and 7, after the first processing step shown in FIG. 4C, the electrode 2 is formed by applying nickel plating to the end face of the tip 31 without performing the etching step of FIG. Furthermore, it is sectional drawing which shows the case where a gold plating is given after that. FIG. 6 shows a case where the thickness of the nickel plating is about 1 μm, and FIG. 7 shows a case where the thickness of the nickel plating is about 10 μm. 3 to 7 are explanatory diagrams conceptually expressed such as highlighting the characteristic portions for easy understanding of the description. For example, the actual dimensions such as the thickness of the plating layer and the thickness of the electric wire 3 are not necessarily illustrated. It does not match the ratio.

  As described above, each time the substrate 100 is set on the inspection jig 7, the rear end portion of the probe Pr elastically contacts the surface plating layer 4 with a predetermined contact pressure. The plating layer 4 is worn, and the electrode 2 under the surface plating layer 4 is also worn.

  As shown in FIG. 6, when the thickness of the nickel plating is about 1 μm, it is easy to form the electrode 2 on the tip 31 and the surface plating layer 4 on the electrode 2. However, if the electrode 2 is thin, the electrode 2 is easily worn by the contact of the rear end portion of the probe Pr.

  8 and 9, using the probe Pr having a diameter of 70 μm, the pressing of the substrate 100 against the support block E is repeated 2 million times as shown in FIGS. 1 and 2, that is, the probe Pr is applied to the surface plating layer 4. The photograph which image | photographed the surface plating layer 4 and the electrode 2 after making it contact 2 million times of the formed electrode 2 is shown. FIG. 8 shows an experimental result when the electrode structure 1 shown in FIGS. 3 and 5D is used, and FIG. 9 shows an experimental result when the electrode structure according to the comparative example shown in FIG. 6 is used. Is shown.

  In the example shown in FIG. 8, although the surface plating layer 4 was scraped, the scraping depth from the surface plating layer 4 surface was only 1.7 μm, and the electric wire 3 was not exposed. On the other hand, in the example shown in FIG. 9, the scraping depth from the surface plating layer 4 surface reached 6.4 μm, and the electric wire 3 was exposed. That is, in the example shown in FIG. 9, since the electrode 2 is thin, the nickel electrode 2 is scraped off and the rear end of the probe Pr reaches the copper electric wire 3. Then, since copper is softer than nickel, as shown in FIG. 9, wear due to the rear end of the probe Pr is large, and the shaving depth of the electric wire 3 increases.

  Thus, as in the comparative example shown in FIG. 6, when the electrode 2 is thin, the copper wire 3 is greatly shaved and a large amount of copper wear powder is generated, and a short circuit occurs between the adjacent electrodes 2. Defects may occur. Moreover, if the copper electric wire 3 is exposed, the tip 31 of the electric wire 3 may be oxidized, and the contact resistance between the probe Pr and the electric wire 3 may increase. Therefore, there is a possibility that the inspection using the inspection jig 7 cannot be performed normally.

  On the other hand, in the case of the electrode structure 1 shown in FIG. 3, since the high hardness electrode 2 is formed thick, as shown in FIG. 8, the scraping depth from the surface plating layer 4 surface is 1.7 μm. Since the electric wire 3 is not exposed, copper wear powder is not generated, and nickel wear powder is little generated. Therefore, the possibility of short circuit failure occurring between adjacent electrodes 2 is reduced, and the tip 31 of the electric wire 3 is also prevented from being oxidized. Therefore, even after the substrate inspection is repeated 2 million times, the inspection is performed. The possibility that the inspection using the jig 7 cannot be normally performed is reduced.

  On the other hand, as shown in FIG. 7, when the thickness of the nickel plating is increased without etching the electric wire 3, the electrode 2 expands in the lateral direction, which causes a disadvantage that the interval between the adjacent electrodes 2 is narrowed. . Moreover, since the formation of the electrode 2 by plating has a large manufacturing variation, as shown in FIG. 7, the electrode height varies among the electrodes 2. If the electrode height varies, the inspection jig 7 may vary in the protruding amount and the pressing force of the probe Pr with respect to the inspection point of the substrate 100, and the inspection accuracy of the substrate 100 may be reduced.

  Further, when plating is performed on the tip 31 which is flush with the surface 11 by the plating method to increase the plating thickness, an oxide film is formed in a portion in contact with oxygen in the air during the plating operation, and the plating is easily peeled off. There is a risk. Furthermore, as shown in FIG. 7, since the side surface of the electrode 2 is exposed to the air, when the surface plating layer 4 is formed by plating the surface of the electrode 2, the area of the surface plating layer 4 increases, There is a disadvantage that the amount of use increases and the cost increases. In FIG. 7, the thickness of the electrode 2 is emphasized, but in practice, the thick electrode 2 is formed by plating on the surface 11 and the front end 31 without etching the electric wire 3. With difficulty.

  On the other hand, according to the manufacturing method of the electrode structure 1 shown in FIGS. 4 and 5 and the electrode structure 1 shown in FIG. 3, the thickness of the electrode 2 can be increased and the wear due to the contact of the probe Pr can be reduced. Easy. Thereby, the possibility that the electrode 2 is worn and the electric wire 3 is exposed can be reduced, and generation of copper wear powder and oxidation of the tip 31 can be suppressed. As a result, the durability of the electrode structure 1 can be improved. In addition, as shown in FIG. 7, the distance between the adjacent electrodes 2 is appropriately maintained because the electrode 2 does not expand in the lateral direction as compared with the case where the thickness of the nickel plating is increased without etching the electric wire 3. In addition, since the side surface of the electrode 2 is not exposed to the air, the area of the surface plating layer 4 is minimized, and the consumption of gold is reduced, resulting in a reduction in cost.

  Further, in the second processing step of FIG. 5C, the tip of the electrode 2 is flush with the surface 11, so that the tip position is made uniform between the electrodes 2. On top of that, since the thin surface plating layer 4 of about 1 μm is formed, the tip surface position of each surface plating layer 4 is also made uniform. As a result, the probe Pr protrudes from the inspection point of the substrate 100 in the inspection jig 7. The amount and pressing force are made uniform. As a result, the inspection accuracy of the substrate 100 is improved.

  The surface plating layer 4 is preferable in terms of preventing the electrode 2 from being oxidized. However, the surface plating layer 4 does not necessarily have to be formed on the surface of the electrode 2, and the surface plating step does not have to be performed. Further, the second metal used for the surface plating layer 4 may not be gold.

  The second processing step is preferable in that the tip of the electrode 2 can be made flush with the surface 11 with high accuracy. However, it is not always necessary to execute the second processing step. The tip of the electrode 2 may be processed to be substantially flush with the surface 11 by controlling the plating thickness in the plating process.

  Further, the tip of the electrode 2 is not necessarily flush with the surface 11. For example, the tip of the electrode 2 may be located at a position recessed from the opening 14 in the through hole 12.

  Moreover, the electric wire 3 does not necessarily need to be copper, and the electrode 2 (first metal) does not necessarily need to be nickel. The electrode 2 (first metal) may be any metal that is harder than the electric wire 3.

  Moreover, although the electrode structure 1 showed the example integrated in the inspection jig 7, the electrode structure 1 is not restricted to what is integrated in the inspection jig 7. FIG. The electrode structure 1 may be used for uses other than the inspection apparatus.

DESCRIPTION OF SYMBOLS 1 Electrode structure 2 Electrode 3 Electric wire 4 Surface plating layer 5 Resin 7 Inspection jig 10 Energizing part 11 Surface 12 Through-hole 13 Base material part 14 Opening part 31 Tip 100 Board | substrate E Support block Pr Probe

Claims (8)

An insulating base material having a substantially flat surface and having a through hole extending in a direction intersecting the surface;
One end portion is inserted into the through hole, and the wire fixed to the through hole so that the tip of the one end portion is located at a position deeper than the opening where the through hole opens in the surface,
An electrode structure comprising: an electrode formed on the tip by a first metal having a hardness higher than that of the electric wire.   The electrode structure according to claim 1, wherein the electrode is substantially flush with the surface.   The electrode structure according to claim 1 or 2, wherein a surface plating layer made of a second metal is formed on the surface of the electrode. The first metal is nickel;
The electrode structure according to claim 3, wherein the second metal is gold. The electrode structure according to any one of claims 1 to 4,
A probe having a wire shape;
An inspection jig comprising: a support for guiding one end of the probe to an inspection point of a substrate to be inspected and guiding the other end of the probe to the electrode of the electrode structure. With respect to an insulating base material having a substantially flat surface and having a through hole extending in a direction intersecting with the surface, the through hole is formed from the opposite side of the opening where the through hole opens on the surface. An insertion step of inserting one end of the wire into the one end, and fixing the one end of the wire to the through hole;
A first processing step of processing the one end so that the end surface of the one end and the surface of the base member are flush with each other;
Etching process that etches the one end from the opening side and deepens the tip of the one end from the opening; and
And a plating step of forming an electrode by plating the tip of the one end with a first metal having a hardness higher than that of the electric wire.   The method for manufacturing an electrode structure according to claim 6, further comprising a second processing step of processing the electrode substantially flush with the surface.   The method for manufacturing an electrode structure according to claim 6 or 7, further comprising a surface plating step of forming a surface plating layer on the surface of the electrode by plating with a second metal.