JP3804370B2 - Module substrate and manufacturing method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a module substrate for electrically connecting to a mother board by soldering and a manufacturing method thereof.
[0002]
[Prior art]
  In recent years, with the miniaturization of electronic devices, the density of electronic components such as semiconductor ICs, active components, and passive components mounted on circuit boards has been increasing. For this reason, from the viewpoint of the importance of intermediate inspection, ease of mounting, etc., after the electronic components are pre-assembled to the module substrate in advance, this module substrate is attached to the motherboard using a joining means such as soldering (for example, Japanese Patent Laid-Open No. 63-204693).
[0003]
  Such a conventional module substrate is shown in FIG.14Or figure17As shown in FIG. 1, the substrate 1 is composed of a substantially rectangular insulating resin material and a wiring made of a conductor, and a plurality of end surface through holes 2 provided in a concave curve on the outer periphery of the substrate 1. Each of the end face through holes 2 is constituted by a substantially semicircular end face opening groove 2A and an end face electrode 2B provided on the inner wall surface of the end face opening groove 2A, and the end face opening groove 2A has a solder. 2C is filled. Further, the end face electrode 2B is connected to the wiring 3 provided on the surface side of the substrate 1, and the end face electrode 2B is connected to the electronic component 4 provided in the center on the front side of the substrate 1 through the wiring 3.
[0004]
  Then, the module substrate configured as described above is heated in a state where it is placed on the mother board 5. As a result, the solder 2C of the end surface through hole 2 is melted and attached to the electrode pad 6 on the mother board 5 and can be soldered. As a result, there is a gap between the end face electrode 2B and the electrode pad 6.15And figure16As shown, the fillet 7 is formed in which the solder has a smooth curved shape.
[0005]
[Problems to be solved by the invention]
  By the way, in the above-described prior art, in order to electrically connect the electronic component 4 mounted on the surface of the substrate 1 to the electrode pad 6 of the motherboard 5, the wiring 3 made of a conductor is provided on the surface of the substrate 1. . The substrate 1 may be a multilayer substrate in which a grounding wiring pattern for connecting the electronic component 4 to the ground is provided inside the substrate 1.
[0006]
  In this case, the coefficient of thermal expansion is different between the wiring 3 made of a conductor and the resin material constituting the substrate 1, so that when the substrate 1 is processed or heated by soldering,15A curved warp as shown in the arrow A direction inside may occur in the substrate 1. Similarly, the mother board 5 may be warped, and a gap may be formed between the end face electrode 2 </ b> B of the substrate 1 and the electrode pad 6 of the mother board 5.
[0007]
  As a result, even if the solder 2C of the end face through-hole 2 is melted by heating, the surface tension of the solder 2C17As shown in FIG. 2, there is a problem that the end surface electrode 2B cannot be connected to the electrode pad 6 because it is substantially spherical and does not contact the electrode pad 6 of the mother board 5.
[0008]
  Further, in recent years, there has been a tendency to make the substrate 1 and the mother board 5 thinner as the electronic equipment becomes thinner. For this reason, warpage of the substrate 1 and the mother board 5 is increased, and connection failure between the end face electrode 2B and the electrode pad 6 is likely to occur.
[0009]
  The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to provide a module substrate capable of reliably connecting an end face electrode to a motherboard even when the substrate or the like is warped, and its manufacture. It is to provide a method.
[0010]
[Means for Solving the Problems]
  In order to solve the above-described problems, the present invention provides a module comprising a substrate on which an electronic component is mounted on the front surface side, and an end surface electrode provided on an end surface forming the outer peripheral edge of the substrate and connected to the electronic component. Applied to the substrate.
[0011]
  The feature of the module substrate according to the invention of claim 1 is:The substrate is provided with an end face opening groove that opens to an end face, and the end face electrode is provided on a part of the inner wall surface of the end face opening groove,For the end electrodeSaidProvide solder to connect to the motherboard provided on the back side of the substrate, the solderAn electrode facing portion facing the end surface electrode located in the end surface opening groove, and from the electrode facing portionProjects forward from the end face of the boardA front projecting portion provided on the surface of the substrate, and an electrode connection portion located around the end surface opening groove and connected to the end surface electrode, and the electronic component from the electrode connection portion. A wiring composed of a line portion extending toward the substrate is provided, and a part of the electrode connection portion of the wiring that is located closer to the end face side of the substrate than the end face electrode is covered with a resist film.That is.
[0012]
  With this configuration, the solder provided on the end face electrode is melted by heating the module substrate while it is placed on the mother board. At this time, the part of the melted solder that contacts the end face electrode is maintained in the joined state with the end face electrode, but the part that protrudes forward from the end face of the board loses what it supports and is on the back side of the board. Droop. Therefore, even when a gap is formed between the substrate and the electrode pad of the mother board, the end face electrode and the electrode pad can be connected by molten solder, and a fillet is formed between them. Can do.
[0013]
  Also, GroupBy heating the plate or the like, the solder accommodated in the end face opening groove is melted. At this time, the electrode facing portion of the solder retains the joined state with the end surface electrode, but the front protruding portion loses what it supports, and therefore hangs down to the back side of the substrate. As a result, even when a gap is formed between the substrate and the electrode pad of the mother board, the end face electrode and the electrode pad can be connected by molten solder.
[0014]
  Since the end face electrode is provided on a part of the inner wall surface of the end face opening groove,When the solder is melted by heating, the melted solder is supported in a state of being attached to the substrate by the end face electrode provided on a part of the inner wall surface of the end face opening groove. On the other hand, the solder protruding from the end surface side of the substrate hangs down to the back side of the substrate because there is nothing to support the portion of the solder contained in the end surface opening groove that does not contact the end surface electrode. Moreover, since there is nothing to support also the part which does not contact an end surface electrode among the solder accommodated in the end surface opening groove | channel, it hangs down to the back surface side of a board | substrate with the solder protruded from the end surface side of a board | substrate. For this reason, the amount of solder drooping on the back side of the substrate can be increased, and even when a large gap is formed between the substrate and the electrode pad of the mother board, the gap between the end surface electrode and the electrode pad can be increased. Can be connected by soldering.
[0015]
  In particular, Claims1InventionsoIs provided on the front surface side of the substrate with a wiring composed of an electrode connection portion located around the end surface opening groove and connected to the end surface electrode, and a line portion extending from the electrode connection portion toward the electronic component. The portion of the electrode connecting portion located on the end face side of the substrate with respect to the end face electrode is covered with a resist film.HaveThe
[0016]
  In this case, since the resist film covers the portion of the electrode connection portion of the wiring located closer to the end face of the substrate than the electrode, the electrode connection portion of this portion does not come into contact with the solder. When the solder is melted, the solder in the part in contact with the electrode is attracted to the electrode and the electrode connecting portion and the joined state is maintained, but the solder in the other part has nothing to support, so the board can be easily Can be hung on the back side.
[0017]
  Claims2InventionFeatures of the configuration adopted byIsThe substrate is provided with an end surface opening groove that opens to the end surface, the end surface electrode is provided on a part of the inner wall surface of the end surface opening groove, and the end surface electrode is connected to a motherboard provided on the back side of the substrate The solder is formed by an electrode facing portion facing the end surface electrode located in the end surface opening groove, and a front projecting portion provided so as to protrude forward from the end surface of the substrate from the electrode facing portion. Configured and saidOn the surface side of the substrate,SaidProvided is a wiring composed of an electrode connecting portion located around the end face opening groove and connected to the end face electrode and a line portion extending from the electrode connecting portion toward the electronic component, and the electrode connecting portion of the wiring is connected to the end face electrode. The configuration extends to a position corresponding to the inner wall surface.
[0018]
  Thus, the electrode connection portion of the wiring extends to a position corresponding to the inner wall surface of the electrode, and is not provided on the end surface side of the substrate from the inner wall surface of the electrode. For this reason, the site | part which contacted the electrode among the solder accommodated in the end surface opening groove | channel contacts the electrode connection part of wiring, and another site | part does not contact an electrode connection part. Therefore, when the solder is melted, the solder in the portion in contact with the electrode is attracted to the electrode and the electrode connecting portion and the joined state is maintained, but the solder in the other portion has no support, so it is easy. Can be suspended on the back side of the substrate.
[0019]
  TheAnd claims3The invention comprises a substrate on which an electronic component is mounted on the surface side, and an end face electrode provided on the outer peripheral edge of the substrate and connected to the electronic component, and solder for connecting to the mother board is connected to the end face electrode. A method for manufacturing a module substrate, wherein a through-hole is formed in a processing substrate, an electrode film is provided on an inner wall surface of the through-hole, and a part of the through-hole is cut out through the processing substrate. Forming a solder accommodation hole adjacent to the hole, cutting the processing substrate through the solder accommodation hole using a pushback mold, and accommodating and fixing the solder in the through hole and the solder accommodation hole; The solder is provided so as to protrude forward from the end face of the substrate.
[0020]
  As a result, it is possible to form the end face electrode in which the solder accommodation hole is provided adjacent to the through hole and the inner wall surface is exposed toward the solder accommodation hole. Next, the substrate for processing is cut out from the substrate for processing by cutting the substrate for processing through the solder receiving hole using a pushback mold, and the substrate is pushed back to the original position. At this time, the end face opening groove can be provided on the end face of the substrate, and the end face opening groove can be continuously arranged in the solder receiving hole protruding forward from the end face of the substrate. Next, when the processing substrate is cut and the solder is accommodated and fixed in the through hole and the solder accommodation hole, the solder can be separated from the solder accommodation hole, although the solder is joined to the end face electrode. As a result, when the substrate is separated from the processing substrate, the solder can be attached to the end surface electrode of the substrate.WhenIn both cases, the solder can be protruded from the end surface of the substrate by an amount that protrudes forward from the end surface of the substrate in the solder receiving hole.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
  Hereinafter, a module substrate according to an embodiment of the present invention will be described with reference to FIGS.13This will be described in detail based on the above.
[0022]
  First, FIG. 1 to FIG. 10 show a first embodiment of the present invention. In FIG. 1, reference numeral 11 denotes a laminate formed by alternately laminating, for example, an insulating resin material and a wiring pattern (not shown) made of a conductor. A plurality of end surface through-holes 13 to be described later are formed on the outer peripheral edge of the substrate 11. In addition, the board | substrate 11 is formed in the substantially square shape whose vertical-horizontal length dimension is about 30 mm. Further, an electronic component 12 such as a semiconductor IC, an active component, or a passive component is mounted on the center side of the surface 11A of the substrate 11.
[0023]
  .. Are end surface through holes provided on the end surface 11C of the four sides that form the outer peripheral edge of the substrate 11. Each of the end surface through holes 13 includes an end surface opening groove 14 and an end surface electrode 15 described later. Yes.
[0024]
  14, 14,... Are end face opening grooves provided in a concave curved shape on the outer peripheral edge of the substrate 11. Each of the end face opening grooves 14 extends from the end face 11C of the substrate 11 to about 1 mm as shown in FIG. A solder accommodating portion 14A that extends substantially linearly and accommodates a solder 17 described later, and is provided on the bottom side of the groove continuously to the solder accommodating portion 14A and cooperates with the solder accommodating portion 14A to accommodate the solder. It is comprised by the circular electrode formation part 14B. The electrode forming portion 14B has an inner diameter of about 1 mm, and an end face electrode 15 described later is formed on the inner wall surface thereof. The end face opening groove 14 is provided so as to penetrate in the thickness direction of the substrate 11, and a substantially semi-ellipsoidal opening is formed in the front surface 11 </ b> A and the back surface 11 </ b> B of the substrate 11.
[0025]
  15 is an end face electrode provided on a part of the inner wall surface of the end face opening groove 14, and the end face electrode 15 is located on the groove bottom side (back side) of the end face opening groove 14 and is an electrode forming portion. It is formed in a state of covering 14B.
[0026]
  16 is a wiring connecting the end face electrode 15 and the electronic component 12, and the wiring 16 is located around the end face opening groove 14 and connected to the end face electrode 15, and the arc-shaped electrode connecting portion 16A. The line portion 16B extends from the electrode connection portion 16A toward the center portion of the substrate 11 and is connected to the electronic component 12.
[0027]
  17, 17,... Are solders housed and fixed in the respective end face opening grooves 14. The solder 17 is located in the end face opening grooves 14 and faces the end face electrodes 15. It is constituted by a substantially rectangular forward projecting portion 17B provided so as to project forward from the end surface 11C of the substrate 11 from the portion 17A. Then, the solder 17 is melted by being heated in a heating furnace or the like, and its tip hangs down to the back surface 11B side of the substrate 11. Thus, the solder 17 is in contact with the electrode pad 6 of the mother board 5 to form a fillet 25 described later between the end face electrode 15 and the electrode pad 6.
[0028]
  The module substrate according to the present embodiment has the above-described configuration. Next, a manufacturing method thereof will be described with reference to FIGS. In the present embodiment, as shown in FIG. 3, a case where one module substrate is processed from one processing substrate 21 is taken as an example.
[0029]
  First, in the through hole processing step shown in FIG. 3, for example, a processing substrate 21 for manufacturing one module substrate is punched with a circular mold, and a large number of through holes 22 are processed into a row (frame shape). To do.
[0030]
  Next, in the wiring processing step shown in FIGS. 4 and 5, a mask such as a photoresist is formed on the surface side of the processing substrate 21, and the wiring 16 'is provided by performing an etching process. At this time, the electrode connection portion 16 </ b> A ′ of the wiring 16 ′ is formed in a ring shape that is located around the through hole 22 and surrounds the through hole 22. Further, a string-like line portion 16B ′ is connected to the electrode connecting portion 16A ′, and the line portion 16B ′ extends toward the center side of the processing substrate 21.
[0031]
  After the wiring processing step, the through hole 22 is plated as an electrode film processing step, and the electrode film 23 is formed over the entire inner wall surface of the through hole 22. At this time, the electrode film 23 is connected to the electrode connection portion 16A 'of the wiring 16'.
[0032]
  Next, in the solder accommodating hole processing step shown in FIG. 6, the processing substrate 21 is punched out with a rectangular mold, and a substantially rectangular solder accommodating hole 24 is processed adjacent to each through hole 22. At this time, since substantially half of the through hole 22 is cut off by the solder receiving hole 24, the remaining through hole 22 is formed with a substantially semicircular arc-shaped end face electrode 15 and the end face electrode 15 has a substantially U shape. A wiring 16 composed of a letter-shaped electrode connecting portion 16A and a line portion 16B is connected. The solder accommodating hole 24 extends from the through hole 22 toward the outer edge side of the processing substrate 21, and is provided across the position to be the end surface 11 </ b> C when the substrate 11 is cut by a substrate cutting process described later. .
[0033]
  Next, in the substrate cutting step shown in FIG. 7, the processing substrate 21 is cut at a position indicated by a two-dot chain line in FIG. At this time, although the processing substrate 21 is separated into the substantially rectangular substrate 11 and the remaining frame portion 21A, the substrate 11 is returned to the position in the frame portion 21A by using a so-called pushback mold. Then, since the processing substrate 21 is cut through the solder accommodating hole 24, the substrate 11 is formed with the end surface through hole 13 opened to the end surface 11C, and the end surface between the substrate 11 and the frame portion 21A. The solder accommodating hole 24 integrated with the through hole 13 remains.
[0034]
  Next, in the solder accommodating process shown in FIG. 8, the molten solder 17 is accommodated (filled) in the solder accommodating hole 24 and the through hole 22 (end surface through hole 13), cooled, and fixed. At this time, the solder 17 adheres to the end face electrode 15 provided on the groove bottom side of the end face through hole 13 and is held in a state in which the inside of the solder accommodation hole 24 is filled. Instead of filling the melted solder 17, paste-like cream solder or granular solder is accommodated in the solder accommodation hole 24 or the like, and the solder 17 is fixed in the solder accommodation hole 24 by heating and cooling it. May be.
[0035]
  Finally, in the substrate separation step shown in FIG. 9, the substrate 11 is removed from the frame portion 21 </ b> A of the processing substrate 21. As a result, the solder 17 is attached to the end face through hole 13 of the substrate 11 and the solder accommodating hole 24 is formed across the substrate 11 and the frame portion 21A. A front projecting portion 17B is formed that projects forward (forward) from the end face 11C.
[0036]
  The module substrate according to the present embodiment is formed by the above-described manufacturing method. Next, a case where the module substrate is bonded onto the motherboard will be described.
[0037]
  First, the module substrate is heated in a state where it is placed on the mother board 5 as in the prior art. Thereby, the melted solder 17 is supported in a state of being attached to the substrate 11 by the end face electrode 15 provided in the end face opening groove 14. At this time, the solder 17 is composed of an electrode facing portion 17A located in the end surface opening groove 14 and a front projecting portion 17B that protrudes further forward than the end surface 11C of the substrate 11, and is soldered only in the end surface opening groove 14 as in the prior art. Compared with the case where 17 is provided, the quantity is large and the weight is also heavy. In addition, since the end face electrode 15 is provided only at a part of the inner wall surface of the end face opening groove 14, the solder accommodated in the solder accommodating portion 14A of the end face opening groove 14 where the end face electrode 15 is not provided. 17 ′ cannot be supported by the end face electrode 15, loses the balance of surface tension, and hangs down to the back surface 11B side of the substrate 11 as indicated by a two-dot chain line in FIG.
[0038]
  As a result, a gap of about 0.4 mm, for example, is formed between the end surface through hole 13 of the substrate 11 and the electrode pad 6 of the mother board 5 as in the case where the substrate 11 is warped. However, since the tip of the solder 17 ′ contacts the electrode pad 6 of the mother board 5, the end face electrode 15 of the substrate 11 and the electrode pad 6 of the mother board 5 can be connected by the molten solder 17 ′. A fillet 25 can be formed.
[0039]
  Thus, in this embodiment, since the solder 17 is configured to protrude forward from the end face 11C of the substrate 11, a large amount of solder 17 can be attached to the end face electrode 15. Therefore, by melting the solder 17, the forward projecting portion 17 </ b> B projecting forward from the end surface 11 </ b> C of the substrate 11 of the solder 17 loses what it supports, so that it continues to the solder 17 joined to the end surface electrode 15 side. , Hangs down to the back surface 11B side of the substrate 11. As a result, the substrate 11 or the like is warped, and a gap is generated between the end surface through hole 13 of the substrate 11 and the electrode pad 6 of the motherboard 5.TheAlternatively, the end face through-hole 13 and the electrode pad 6 can be connected by the drooped solder 17 and the fillet 25 can be formed between them.
[0040]
  Further, since the end face electrode 15 is provided at a part of the inner wall surface of the end face opening groove 14, when the solder 17 is melted by heating or the like, the balance of the surface tension of the solder 17 is easily lost, and the solder 17 is easily made. The substrate 11 can be suspended from the back surface 11B side. Therefore, the warp of the substrate 11 and the like can be absorbed by the solder 17 and the end surface electrode 15 and the electrode pad 6 can be reliably connected.
[0041]
  Further, since the end face opening groove 14 is constituted by the solder accommodating portion 14A opened in the end face 11C of the substrate 11 and the electrode forming portion 14B in which the end face electrode 15 is continuously formed in the solder accommodating portion 14A, the related art. Thus, a larger amount of solder 17 can be accommodated in the end face opening groove 14 than in the case where the end face electrode 15 is provided over the entire inner wall surface of the end face opening groove 14.
[0042]
  Therefore, when the solder 17 is melted, the solder 17 filled in the solder accommodating portion 14A breaks the balance of the surface tension of the entire melted solder 17 in cooperation with the front protruding portion 17B, and is provided in the electrode forming portion 14B. It hangs down to the back surface 11B side of the substrate 11 while continuing to the end face electrode 15. As a result, even when a relatively large gap is formed between the end face electrode 15 and the electrode pad 6, it is possible to reliably connect them.
[0043]
  Further, in the present embodiment, since the pushback mold is used in the substrate cutting process for cutting the substrate 11 from the processing substrate 21, cutting is performed as compared with the case where the processing substrate 21 is cut using a diamond cutter or the like. No chips are generated. For this reason, it is not necessary to clean the substrate 11 and the like after the processing substrate 21 is cut, so that the cleaning of the substrate 11 and the like can be omitted, and the productivity can be improved.
[0044]
  Next, FIG. 11 shows a second embodiment of the present invention. The feature of the present embodiment is that a portion of the wiring connected to the end face electrode is located closer to the end face side of the substrate than the end face electrode. It is in the structure covered with. In the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.
[0045]
  Reference numeral 31 denotes a resist film provided on the surface 11A side of the substrate 11 over substantially the entire surface. The resist film 31 is formed by applying a resist to the surface 11A of the substrate 11 and covers the wiring 16 and the like. The resist film 31 is provided with a semicircular cutout 31 </ b> A that exposes a portion of the electrode connection portion 16 </ b> A of the wiring 16 that is located on the groove bottom side of the end face opening groove 14 connected to the end face electrode 15. Yes. In addition, the resist film 31 is located at both ends of the notch 31A and covers a plurality of covering portions 31B, 31B, which cover the substantially triangular portion of the electrode connection portion 16A located on the end surface 11C side of the substrate 11 relative to the end surface electrode 15. …have. The resist film 31 protects the surface of the wiring 16 and the like and prevents its corrosion.
[0046]
  Thus, this embodiment configured as described above can obtain the same effects as those of the first embodiment. However, in the present embodiment, since both end sides of the electrode connection portion 16A having a substantially U shape are covered with the covering portion 31B of the resist film 31, the solder 17 is electroded when the solder 17 is melted by heating. It is no longer attracted to the connecting portion 16A.
[0047]
  That is, as in the comparative example shown in FIG. 12, when the electrode connection portion 16A of the wiring 16 provided between the end face electrode 15 and the end face 11C side of the substrate 11 is exposed, the melted solder 17 Swells by the surface tension, and tends to be attracted to the electrode connecting portion 16A and spread in the direction indicated by the arrow B. For this reason, the solder 17 located between the end face electrode 15 and the end face 11C of the substrate 11 tends to be attracted to the front surface 11A side of the substrate 11 by the electrode connecting portion 16A and hardly hangs down to the back surface side 11B side.
[0048]
  On the other hand, in the present embodiment, the portion of the electrode connection portion 16A of the wiring 16 that is located closer to the end face 11C side of the substrate 11 than the end face electrode 15 is covered with the resist film 31. No contact is made with both end sides of the electrode connecting portion 16A. At this time, the solder 17 disposed on the end surface 11C side of the substrate 11 with respect to the end surface electrode 15 loses what it supports, and therefore easily hangs down on the back surface 11B side of the substrate 11. Thereby, the solder 17 accommodated in the solder accommodating portion 14 </ b> A together with the front projecting portion 17 </ b> B of the solder 17 can be reliably suspended, and the gap between the end face electrode 15 and the electrode pad 6 can be compensated.
[0049]
  Next, FIG. 13 shows a third embodiment of the present invention, and the feature of this embodiment is that the electrode connection portion of the wiring is extended to a position corresponding to the inner wall surface of the end face electrode. . In the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.
[0050]
  .. Are end surface through holes provided in the end surface 11C of the substrate 11, and each end surface through hole 41 is constituted by an end surface opening groove 42 and an end surface electrode 43, which will be described later.
[0051]
  42, 42,... Are substantially rectangular end surface opening grooves provided in the end surface 11C of the substrate 11, and each end surface opening groove 42 extends in a substantially straight line from the end surface 11C of the substrate 11. And a substantially U-shaped electrode forming portion 42B provided on the groove bottom side continuously to the solder accommodating portion 42A.
[0052]
  43 are end face electrodes provided on a part of the inner wall surface of the end face opening groove 42. The end face electrode 43 is located on the groove bottom side of the end face opening groove 42 and covers the electrode forming portion 42B. It is formed with.
[0053]
  44 is a wiring connecting the end face electrode 43 and an electronic component (not shown), and the wiring 44 is located around the end face opening groove 42 and connected to the end face electrode 43. The connecting portion 44A and a line portion 44B extending from the electrode connecting portion 44A toward the central portion of the substrate 11 are configured. Further, although the electrode connection portion 44 </ b> A of the wiring 44 extends to a position corresponding to the inner wall surface of the end face electrode 43, it does not extend to the end face 11 </ b> C side of the substrate 11 from the position of the end face electrode 43. For this reason, the surface 11 </ b> A of the substrate 11 is exposed on the end surface 11 </ b> C side of the substrate 11 relative to the end surface electrode 43 in the periphery of the end surface opening groove 42.
[0054]
  45, 45,... Are solders housed and fixed in the respective end face opening grooves 42. The solder 45 is located in the end face opening grooves 42 and faces the end face electrodes 43. It is constituted by a substantially rectangular front projecting portion 45B provided so as to project forward from the portion 45A to the front surface 11C of the substrate 11.
[0055]
  Thus, the same effects as those of the first embodiment can be obtained in this embodiment. However, in the present embodiment, the electrode connecting portion 44A of the wiring 44 is configured to extend to a position corresponding to the inner wall surface of the end face electrode 43, and therefore, from the end face electrode 43 of the solder 45 accommodated in the end face opening groove 42. The part located on the end surface 11C side of the substrate 11 does not contact the electrode connecting portion 44A and is not attracted to the surface 11A side of the substrate 11 by the electrode connecting portion 44A.
[0056]
  For this reason, the solder 45 accommodated in the solder accommodating portion 42 </ b> A is hung on the back surface 11 </ b> B side of the substrate 11 together with the front protrusion 45 </ b> B of the solder 45 without covering the wiring 44 with a resist film or the like as in the second embodiment. Can simplify the manufacturing process and improve productivity..
[0057]
  NaOh, the first to the first3In the embodiment, the end surface opening grooves 14, 42, 52 are formed in a semicircular hole shape, a quadrangular shape, a semicircular shape, or the like, but may be, for example, an elliptical shape or other rectangular shapes such as a pentagonal shape. It may be formed.
[0058]
【The invention's effect】
  As described above in detail, according to the first aspect of the present invention, since the solder is projected forward from the end face of the substrate, a large amount of solder can be attached to the end face electrode. For this reason, by melting the solder, the portion protruding from the end surface of the substrate of the solder loses what it supports, so that it can be suspended from the back surface of the substrate while continuing to the solder joined to the end surface electrode side. . Therefore, when the substrate is warped, a gap is generated between the end face electrode of the substrate and the electrode pad of the motherboard.TheAlternatively, the end face electrode and the electrode pad can be connected by the drooping solder, and a fillet can be formed between them.
[0059]
  Also, GroupThe plate is provided with an end face opening groove that opens to the end face, an end face electrode is provided on the inner wall surface of the end face opening groove, and the solder is located in the end face opening groove and faces the end face electrode, and the electrode facing portion Since the front protrusion portion provided so as to protrude forward from the end surface of the substrate from the portion, when the solder is melted by heating, the electrode facing portion of the solder is maintained in the bonding state with the end surface electrode, The front projecting portion loses what it supports and hangs down on the back side of the substrate. At this time, the melted forward projecting portion hangs down on the back side of the substrate with the solder accommodated in the end surface opening groove, so that a relatively large gap is formed between the end surface electrode of the substrate and the electrode pad of the motherboard. You can connect between them even when
[0060]
  Also,endSince the surface electrode is provided at a part of the inner wall surface of the end face opening groove, when the solder is melted by heating or the like, it is easy to break the balance of the surface tension of the solder, and the solder is easily suspended on the back side of the substrate. Can be made. For this reason, the curvature of a board | substrate etc. is absorbed with solder and it can connect between an end surface electrode and an electrode pad reliably.
[0061]
  In particular, Claims1InventionThenSince the portion of the wiring electrode connection portion that is located closer to the end face side of the substrate than the end face electrode is covered with the resist film, the melted solder does not contact the electrode connection portion of the relevant portion. At this time, the solder protruding forward from the end surface loses what is supported together with the solder disposed on the end surface side of the substrate relative to the end surface electrode, so that it easily hangs down to the back surface side of the substrate. Thereby, the solder accommodated in the solder accommodating portion of the end face opening groove can be surely suspended, and the gap between the end face electrode and the electrode pad can be compensated.
[0062]
  Claims2According to the invention, since the electrode connecting portion of the wiring is configured to extend to a position corresponding to the inner wall surface of the end face electrode, the portion of the solder accommodated in the end face opening groove is located closer to the end face side of the substrate than the end face electrode Is not brought into contact with the electrode connecting portion and is not attracted to the surface side of the substrate by the electrode connecting portion. For this reason, in addition to the solder protruding forward from the end surface of the substrate, the solder accommodated in the end surface opening groove can also hang down to the back surface side of the substrate, and the warpage of the substrate or the like can be absorbed..
[0063]
  TheAnd claims3According to the invention, since the substrate is cut from the processing substrate using the pushback mold, chips are generated due to the cutting as compared with the case where the processing substrate is cut using a diamond cutter or the like. There is nothing. For this reason, it is not necessary to clean the substrate or the like after cutting the processing substrate, the substrate or the like can be omitted, and productivity can be improved.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a module substrate according to a first embodiment of the present invention.
2 is an enlarged perspective view of a main part showing an enlarged end surface through hole in FIG. 1; FIG.
FIG. 3 is a plan view showing a state where through holes are formed in a processing substrate.
FIG. 4 is a plan view showing a state in which wiring is formed around a through hole and an electrode film is provided in the through hole.
FIG. 5 is an enlarged plan view of a main part showing a part a in FIG. 4 in an enlarged manner;
FIG. 6 is an enlarged plan view of a main part showing a state in which a solder accommodation hole is formed adjacent to a through hole.
FIG. 7 is a plan view showing a state in which a processing substrate is cut by a pushback mold.
FIG. 8 is an enlarged plan view of a main part showing a state in which solder is accommodated in the through hole and the solder accommodation hole in FIG. 7;
FIG. 9 is an essential part enlarged plan view showing a state in which the module substrate is removed from the processing substrate.
FIG. 10 is an enlarged cross-sectional view of a main part showing a state in which the module substrate according to the first embodiment is bonded to a mother board.
FIG. 11 is an enlarged perspective view of a main part showing an enlarged end surface through hole according to a second embodiment.
FIG. 12 is an enlarged perspective view of a main part showing an enlarged end surface through hole according to a comparative example of the second embodiment.
FIG. 13 is an enlarged perspective view of a main part showing an enlarged end surface through hole according to a third embodiment.
[FIG.It is a perspective view showing a module substrate according to the prior art.
[FIG.]FIG.It is sectional drawing which shows the state which joined the inside module board to the motherboard.
[FIG.]FIG.It is a principal part expanded sectional view which expands and shows an inner end surface through-hole.
[FIG.] Shows a state where the substrate is warped and a gap is formed between the end face through hole and the electrode padFIG.It is a principal part expanded sectional view of the same position.
[Explanation of symbols]
  5 Motherboard
  6 Electrode pads
  11 Substrate
  12 Electronic parts
  13, 41End face through hole
  14,42End face opening groove
  14A, 42A Solder receiving part
  14B, 42B electrode forming part
  15, 43End face electrode
  17, 45solder
  17A, 45AElectrode facing part
  17B, 45BFront protrusion
  21 Substrate for processing
  22 Through hole
  24 Solder receiving hole
  25 fillet
  16, 44wiring
  44AElectrode connection
  44BTrack section
  31 resist film

Claims (3)

In a module substrate comprising a substrate on which an electronic component is mounted on the surface side, and an end surface electrode provided on an end surface forming an outer peripheral edge of the substrate and connected to the electronic component ,
The substrate is provided with an end face opening groove that opens to the end face,
The end surface electrode is provided on a part of the inner wall surface of the end surface opening groove,
The said end face electrodes are provided solder for connection to a mother board provided on a rear surface side of the substrate,
The solder is composed an electrode facing portion facing the edge electrode located on the end-face opening groove, by a front protrusion which protrudes from the electrode facing portion in front of the end face of the substrate,
Provided on the surface side of the substrate is a wiring composed of an electrode connecting portion located around the end face opening groove and connected to the end face electrode, and a line portion extending from the electrode connecting portion toward the electronic component,
A module substrate characterized in that a portion of the electrode connection portion of the wiring located closer to the end face side of the substrate than the end face electrode is covered with a resist film . In a module substrate comprising a substrate on which an electronic component is mounted on the surface side, and an end surface electrode provided on an end surface forming an outer peripheral edge of the substrate and connected to the electronic component,
The substrate is provided with an end face opening groove that opens to the end face,
The end surface electrode is provided on a part of the inner wall surface of the end surface opening groove,
The end face electrode is provided with solder for connecting to a mother board provided on the back side of the substrate,
The solder is constituted by an electrode facing portion that is located in the end face opening groove and faces the end face electrode, and a front protruding portion that is provided to protrude forward from the end face of the substrate from the electrode facing portion,
Provided on the surface side of the substrate is a wiring composed of an electrode connecting portion located around the end face opening groove and connected to the end face electrode, and a line portion extending from the electrode connecting portion toward the electronic component ,
Module substrate electrode connecting portion of the wiring, characterized in that it has a structure extending to a position corresponding to the inner wall surface of the end surface electrode.   A module comprising a substrate on which an electronic component is mounted on the surface side, and an end face electrode provided on an outer peripheral edge of the substrate and connected to the electronic component, the end face electrode being provided with solder for connecting to a motherboard A method for manufacturing a substrate, wherein a through hole is formed in a processing substrate, an electrode film is provided on an inner wall surface of the through hole, and a part of the through hole is cut away from the processing substrate to be adjacent to the through hole. A solder receiving hole is formed, the processing substrate is cut through the solder receiving hole using a pushback mold, and the solder is received and fixed in the through hole and the solder receiving hole. The manufacturing method of the module board | substrate which protrudes ahead and is provided rather than the end surface of this.

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