JP2009099650A - Electronic device and repairing method for electronic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance fall shock resistance of an electronic device which is used for mobile equipment required to have shock resistance and comprises a mounting substrate and a semiconductor device, and to provide the electronic device which has good repair properties. <P>SOLUTION: A side surface of the semiconductor device 2 and the mounting substrate 1 are tightly bonded and fixed together because of providing the mounting substrate 1 having a semiconductor device mounting region where the semiconductor device 2 having a plurality of projection electrodes 5, a plurality of lands 6 corresponding to the projection electrodes 5, and a through-hole 4 disposed at part of an outer periphery of the semiconductor device mounting region, and an adhesive 3 for connecting and bonding portions of a pair of mutually opposite side surfaces of the semiconductor device 2 and an inner peripheral portion of the through-hole 4. Consequently, even when a shock is applied, strain of the mounting substrate 1 is suppressed to deter the semiconductor device 2 from peeling off from the mounting substrate 1, thereby enhancing the shock resistance. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electronic device composed of a mounting substrate and a semiconductor device used for electronic devices, particularly mobile devices that require impact resistance such as personal computers, and in particular, it has improved drop impact resistance and has repairability. Good electronic device.

  FIG. 16 is a schematic cross-sectional view showing an electronic device 51 in which a conventional ball grid array (hereinafter referred to as “BGA”) type semiconductor device 2 is connected to a mounting substrate 61, and one surface of the semiconductor device 2. A protruding electrode 5 is formed on the substrate.

  FIG. 17 is a schematic cross-sectional view showing a state where the electronic device 51 is subjected to an impact force such as a drop and the mounting substrate 61 is warped. Such warpage of the mounting substrate 61 due to the impact force frequently occurs when the electronic device 51 is incorporated into a portable electronic device such as a notebook personal computer and dropped to cause stress on the mounting substrate 61. Furthermore, with recent miniaturization of equipment, the semiconductor device 2 mounted on the equipment is also required to be miniaturized, so that the protruding electrode 5 tends to be miniaturized.

  When such a device is dropped, the mounting substrate 61 is deflected or vibrated by an impact, and a peeling force acts between the protruding electrode 5 and the mounting substrate 61 as shown in FIG. There is an increased risk of cracking and peeling at the interface with the land (not shown).

  For these measures, conventionally, as shown in FIG. 18, a thermosetting resin underfill 62 is caused to flow into the gap between the mounting substrate 61 and the semiconductor device 2 to cure the mounting substrate 61 and the semiconductor device 2. It was fixed. Further, as shown in FIG. 19, the thermosetting resin adhesive 3 is applied and cured around the semiconductor device 2, and the semiconductor device 2 is bonded and fixed to the mounting substrate 61.

  In these structures, a problem occurs in the semiconductor device 2, and when repairing, it is necessary to scrape the once-cured underfill 62 and the adhesive 3, and many man-hours are required. On the other hand, the mounting structure using the resin composition which mixed the organic-type thermally expansible particle | grains which included the organic solvent as the underfill 62, and the thermosetting adhesive resin is disclosed (for example, patent document 1). reference).

In the case of the mounting structure having such a configuration, the organic solution in the organic thermally expandable particles of the underfill 62 is boiled and vaporized by overheating at the time of repair, so that the cured resin changes to a porous structure, The semiconductor device 2 can be easily detached from the mounting substrate 61.
JP 2005-332970 A

  However, according to Patent Document 1, a foaming agent composed of several micron microcapsules is dispersed in a low-viscosity liquid adhesive. However, it is possible to uniformly disperse the microcapsules in the adhesive due to uneven distribution and sedimentation of the microcapsules. It is very difficult.

  When a semiconductor device applied to an electronic device is peeled from a mounting substrate, since the foaming agent is dispersed and mixed in the adhesive, the peeling portion is not only the interface between the mounting substrate and the protruding electrode, but also the semiconductor device 2 and the under device. It is also present at the interface of the fill 62, where the foaming agent and adhesive remain as residues.

  In this case, most of the underfill 62 remains on the mounting substrate 61 side after the semiconductor device 2 is removed, and there is a problem that it takes a lot of man-hours to remove the resin residue.

  The present invention has been made to solve the above-described problems, and provides an electronic device capable of enhancing the drop impact resistance of an electronic device and easily removing a semiconductor device having some defects from a mounting substrate, and a repair method thereof. To do.

  In order to solve the above problems, an electronic device of the present invention includes a semiconductor device having a plurality of protruding electrodes, a plurality of lands corresponding to the plurality of protruding electrodes of the semiconductor device, and a land region in which the plurality of lands are arranged. A mounting board provided with a through-hole disposed in a part of the outer periphery, and an adhesive for connecting and bonding a part of a pair of side surfaces facing each other and the inner peripheral part of the through-hole in the semiconductor device It is.

  The electronic device according to the present invention includes a side surface of the semiconductor device, a mounting substrate, and a surface inside the mounting substrate, which is an unprecedented surface, which is an inner peripheral portion of a through hole formed in the mounting substrate. Is firmly bonded and fixed, and even when an impact is applied to the mounting board, such as when it is dropped, the mounting board is prevented from being distorted, so that the peeling of the semiconductor device from the mounting board can be suppressed, and the impact resistance is improved. Can do. Note that the mounting surface of the mounting substrate and the adhesive is usually provided not only on the inner peripheral portion of the through hole but also on the outer peripheral portion of the through hole opening in the mounting substrate facing the mounted semiconductor device. The adhesion strength between the semiconductor device and the semiconductor device can be further increased.

  In addition, when the adhesive surface of the semiconductor device with the adhesive in the electronic device described above is configured to be two surfaces of a corner portion where adjacent side surfaces of the semiconductor device intersect, the corner of the semiconductor device that is most easily peeled off from the mounting substrate. By bonding and fixing the side surface of the part to the mounting substrate, the effect of suppressing the peeling of the semiconductor device from the mounting substrate can be more reliably achieved.

  Further, when a defect occurs in a semiconductor device mounted on an electronic device having any one of the above configurations, the adhesive inside the through hole may be excavated and removed with a drill having a smaller diameter than the through hole of the mounting substrate. Therefore, the mounting substrate and the adhesive can be separated, and the semiconductor device can be easily removed.

  In the above configuration, a weak adhesive layer having a lower adhesive strength than that of the inner peripheral portion of the through hole may be formed on the upper surface of the mounting substrate and around the opening portion of the through hole.

  With this configuration, if any defect is found in the semiconductor device, the adhesive inside the through hole is removed by drilling and removing the adhesive inside the through hole with a drill having a smaller diameter than the through hole of the mounting board. The adhesive resin can be easily removed from the surface of the mounting substrate because a weakly adhesive layer is formed around the through hole, and the resin is removed from the surface of the mounting substrate after removing the semiconductor device. A clean surface is obtained without any residue.

  Moreover, the repair method of the electronic device of this invention is equipped with the cutting process which excavates the adhesive agent inside a through-hole with the drill of the outer diameter below a through-hole diameter.

  By adopting such a method, there is no damage to the through hole of the mounting substrate, and the interface between the adhesive and the mounting substrate surface is maintained clean, so that both of them are separated so that it is almost the same as a new product. A repair mounting board is obtained.

  Moreover, it is good also as a repair method which provides the stopper which prescribes | regulates the thickness of the mounting substrate or less to the drill used for the said method, and performs a cutting process. By setting it as such a method, since the depth which excavates can be controlled, the damage to the mounting board | substrate at the time of repair work can be suppressed.

  The mounting substrate of the present invention is a mounting substrate having a substrate for mounting a semiconductor device having a plurality of protruding electrodes, and a plurality of lands corresponding to the plurality of protruding substrates and the plurality of lands are arranged. In this configuration, a part of the outer periphery of the land region includes a through hole penetrating the substrate. With the configuration of the mounting substrate, it is possible to realize a mounting substrate having excellent repair properties as described above.

  According to the electronic device and the electronic device repair method of the present invention, when the device is used, since the through hole and the semiconductor side surface are fixed with an adhesive, the increase in the adhesive area and the anchor effect of the adhesive are combined. When the electronic device receives an impact, it is possible to suppress the solder peeling at the joint portion between the protruding electrode and the land provided at the end portion of the semiconductor device that is easily peeled off.

  On the other hand, at the time of repair, after drilling and removing the thermosetting adhesive inside the through-hole with a drill, the electronic device is heated to melt the solder that connects the protruding electrode of the semiconductor device and the land of the mounting substrate. Can be removed from the mounting substrate. By adopting this configuration, the process can be greatly shortened as compared with the conventional case where the adhesive is scraped off with a knife.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, each thickness, length, etc. in these drawings differ from an actual shape on the drawing preparation. Further, unlike the actual case, the number of protruding electrodes on the semiconductor device is set to be easy to show.

(Embodiment 1)
FIG. 1 and FIG. 2 are a plan view of the mounting substrate of the present invention and a cross-sectional view taken along the broken line 1A-1A. As shown in the figure, a land region 71 in which a plurality of lands 6 corresponding to a plurality of projecting electrodes provided in a semiconductor device (not shown) to be mounted is provided, and the mounting substrate 1 is disposed on the outer periphery of the land region 71. A through hole 4 is provided. The semiconductor device mounted on the mounting substrate 1 can be firmly connected by adhering the inner periphery of the through hole 4 and the side surface of the semiconductor device (not shown) with an adhesive as will be described later. In addition, although FIG. 2 includes the plating layer 7 as described later, the plating layer 7 is not always necessary.

  3 and 4 are diagrams showing the structure of the electronic device 10 according to the first embodiment using the mounting substrate 1, FIG. 3 is a plan view, and FIG. 4 is a cross-sectional view taken along the line 1A-1A in FIG. FIG. 3 shows a state in which a part of the semiconductor device 2 and the adhesive 3 are removed in order to make the structure of the mounting substrate 1 easy to understand.

  The electronic device 10 according to the present embodiment includes a semiconductor device 2 and a part of the outer periphery of the mounting region of the semiconductor device 2 (hereinafter referred to as “semiconductor device mounting region”), that is, in the configuration shown in FIG. A mounting substrate 1 having a through-hole 4 disposed at a position corresponding to the center of opposing short sides 70 of the device 2, a side surface including the short sides 70 of the semiconductor device 2, and a semiconductor device mounting facing the semiconductor device 2. There is provided an adhesive 3 for bonding the upper surface of the mounting substrate 1 located at the outer peripheral portion of the opening portion of the through hole 4 in the region and the inside of the through hole 4. Furthermore, in the mounting substrate 1 of the present embodiment, the plating layer 7 is formed on the inner wall of the through hole 4.

  Note that the positions of the through holes 4 arranged on the outer periphery of the semiconductor device mounting region are not directly below the outer periphery of the semiconductor device, but based on the positional relationship between the side surface of the semiconductor device and the adhesive applied to the side surface of the semiconductor device. The distance from the side surface of the semiconductor device is spaced outward by a dimension determined by the diameter of the through hole 4.

  The semiconductor device 2 is a BGA type semiconductor device, and has a plurality of protruding electrodes 5 arranged in a grid pattern on one surface. In the semiconductor device 2 of the present embodiment, for example, a resin substrate, a ceramic substrate, or a flexible substrate may be used as an interposer, a semiconductor device called CSP (Chip Scale Package) may be used, and an electrode of a semiconductor element Alternatively, a flip chip type semiconductor element in which solder bumps are directly formed may be used.

  The protruding electrode 5 may be formed by a ball set method in which solder balls are mounted, or may be formed by supplying a solder paste by a printing method and performing reflow, or by a plating method.

  Furthermore, the material of the protruding electrode 5 may be at least one of a tin / zinc alloy, a tin / bismuth alloy, a tin / silver alloy, a zinc / bismuth alloy, gold, copper, It may be at least one of nickel, gold-plated nickel and gold-plated copper.

  When the mounting substrate 1 and the semiconductor device 2 are opposed to one surface of the base material, the mounting substrate 1 has conductor lands 6 disposed at positions corresponding to the protruding electrodes 5 included in the semiconductor device 2; In the outer periphery of the semiconductor device mounting region of the mounting substrate 1, a through-hole 4 is provided at a position corresponding to the center portion of the opposing short sides 70 of the semiconductor device 2.

  Moreover, the base material of the mounting substrate 1 is made by impregnating an organic resin such as glass fiber or Kepler with an epoxy resin, a polyimide resin, a polyamide resin, a polyester resin, a benzoxazal resin, a tetrafluoroethylene (TFE) resin, or the like. Various resin substrates can be used, such as those using hardened equipment and those using BT resin.

  In the present embodiment, the installation position of the through hole 4 is the position on the mounting substrate 1 corresponding to the central portion of the semiconductor device mounting region determined by the short side 70 of the semiconductor device 2. 2 may be a position on the mounting substrate 1 corresponding to a position on the other side or all the sides, or may correspond to a position other than the central portion of each side, or further, a plurality of locations on each side. Correspondingly, a predetermined number of through holes 4 may be provided on the mounting substrate 1.

  The conductor of the land 6 is made of copper foil, but a metal layer may be formed on the copper foil. The plated layer 7 on the inner wall of the through hole 4 may be formed by electroless copper plating and electrolytic copper plating, and a metal layer may be formed on the surface of the plated layer 7. For example, the metal layer may include at least one selected from solder, gold, silver, nickel, palladium, and the like.

  As the adhesive agent 3, for example, at least one selected from an epoxy resin, a silicone resin, and a cyanate ester may be included. The epoxy resin may include at least one selected from, for example, bisphenol A type, bisphenol F type, biphenyl type, naphthalene type and the like.

  In addition to the resin component, the component of the adhesive 3 may include at least one selected from a filler, a flame retardant, a pigment, a curing agent, a curing accelerator, and the like. In addition to the above composition, a photoinitiator may be added.

  Hereinafter, a method of manufacturing the electronic device 10 according to the present embodiment will be briefly described with reference to FIGS. On the land 6 of the mounting substrate 1 shown in FIG. 3, for example, a solder paste is supplied by a printing method using a metal mask and a squeegee. Subsequently, the semiconductor device 2 is disposed on the land 6 of the mounting substrate 1, and the protruding electrode 5 and the land 6 of the semiconductor device 2 are soldered by reflow. As a result, the semiconductor device 2 can be mounted on the mounting substrate 1.

  Next, for example, a dispenser is provided on the side surface constituting each side of the semiconductor device 2 shown in FIG. 4, the upper surface of the mounting substrate 1 constituting the outer periphery of the opening of the through hole 4 in the semiconductor device mounting region, and the inside of the through hole 4. The adhesive 3 is applied using

  Finally, the semiconductor device 2 is bonded and fixed to the mounting substrate 1 by heating and curing up to a predetermined time at the curing temperature of the adhesive 3.

  By adopting such a manufacturing method, the electronic device 10 according to the present embodiment is mounted on the side surface of each side of the semiconductor device 2 by being bonded and fixed to the mounting substrate 1 and the through hole 4 with the adhesive 3. The semiconductor device 2 mounted on the substrate 1 suppresses the distortion in the mounting substrate 1 against an impact such as dropping, and improves the impact strength of the solder at the joint between the mounting substrate 1 and the protruding electrode of the semiconductor device 2. be able to.

  Hereinafter, the repair method of the electronic apparatus 10 according to the present embodiment will be described with reference to FIG. 5A to 5D are process cross-sectional views illustrating a process of removing the semiconductor device 2 in the repair work of the electronic device 10 according to the first embodiment of the present invention.

  FIG. 5A shows a state in which an electronic device 10 in which a failed semiconductor device 2 is bonded to the mounting substrate 1 and a drill 11 for excavation are installed facing each other. The outer diameter of the drill 11 for excavation is smaller than the inner diameter of the through hole 4 of the mounting substrate 1, and the drill 11 is provided with a stopper 12 having an outer diameter larger than the inner diameter of the through hole 4.

  FIG. 5B is a cross-sectional view in which the adhesive 3 in the through hole 4 is excavated to the depth at which the stopper 12 of the drill 11 contacts the back surface of the mounting substrate 1 from the back surface to the front surface of the mounting substrate 1.

  As described above, since the stopper 12 comes into contact with the mounting substrate 1, the drillable length of the drill 11 does not exceed the cross-sectional length of the mounting substrate 1. The configuration can be prevented.

  FIG. 5C shows the mounting substrate after the adhesive 3 inside the through-hole 4 is excavated and removed, and then heated to a temperature at which the solder joining the land 6 of the mounting substrate 1 and the protruding electrode 5 of the semiconductor device 2 is melted. 1 is a cross-sectional view showing a state where a failed semiconductor device 2 is removed from 1. FIG.

  FIG. 5D is a cross-sectional view of the mounting substrate 1 after the semiconductor device 2 is removed.

  By adopting such a repair method, the electronic device 10 composed of the mounting substrate 1 and the BGA type semiconductor device 2 of the present embodiment can be used even when the semiconductor device 2 is determined to be defective in the electrical inspection after mounting. The connecting portion between the mounting substrate 1 and the adhesive 3 is divided, and the semiconductor device 2 that has failed can be easily and cleanly removed from the mounting substrate 1.

  As a result, a new semiconductor device can be regenerated as the electronic device 10 bonded to the repaired mounting substrate by a simple repair operation without discarding the mounting substrate 1, thereby greatly reducing the cost.

  As described above, when a plurality of corresponding through holes 4 and a plurality of bonding portions are formed on one side of the semiconductor device 2, the bonding force between the semiconductor device 2 and the mounting substrate 1 is improved. While the freedom degree of the wiring in the board | substrate 1 falls, the effort of the adhesive excavation removal work at the time of repair will increase.

(Embodiment 2)
6 and 7 are views showing the structure of the electronic device 10a according to the second embodiment of the present invention. FIG. 6 is a plan view, and FIG. 7 is a cross-sectional view taken along the line 2A-2A in FIG. FIG. 6 shows a state in which a part of the semiconductor device 2 and the adhesive 3 are removed in order to make the structure of the mounting substrate 1 easy to understand.

  The electronic device 10a according to the present embodiment is opposed to the semiconductor device 2, the mounting substrate 1 having the through holes 4 arranged in the corner portion of the semiconductor device mounting region, the side surface of the corner portion of the semiconductor device 2, and the semiconductor device 2. An adhesive 3 is provided for connecting and bonding the upper surface of the mounting substrate 1 located at the outer periphery of the opening of the through hole 4 at the corner of the semiconductor device mounting region and the inside of the through hole 4. Furthermore, in the mounting substrate 1 of the present embodiment, the plating layer 7 is formed on the inner wall of the through hole 4.

  The semiconductor device 2 is a BGA type semiconductor device, and has a plurality of protruding electrodes 5 arranged in a grid pattern on one surface. In the semiconductor device 2 of the present embodiment, for example, a resin substrate, a ceramic substrate, or a flexible substrate may be used as an interposer, a semiconductor device called CSP (Chip Scale Package) may be used, and an electrode of a semiconductor element Alternatively, a flip chip type semiconductor element in which solder bumps are directly formed may be used.

  The protruding electrode 5 may be formed by a ball set method in which solder balls are mounted, or may be formed by supplying a solder paste by a printing method and performing reflow, or by a plating method.

  Furthermore, the material of the protruding electrode 5 may be at least one of a tin / zinc alloy, a tin / bismuth alloy, a tin / silver alloy, a zinc / bismuth alloy, gold, copper, It may be at least one of nickel, gold-plated nickel and gold-plated copper.

  When the mounting substrate 1 and the semiconductor device 2 are opposed to one surface of the base material, the mounting substrate 1 has conductor lands 6 disposed at positions corresponding to the protruding electrodes 5 included in the semiconductor device 2; A through-hole 4 is provided at a corner portion of the mounting area of the mounting substrate 1 on the semiconductor device.

  In addition, the base material of the mounting substrate 1 is made by impregnating an organic resin such as glass fiber or Kepler with an epoxy resin, a polyimide resin, a polyamide resin, a polyester resin, a benzoxazal resin, a tetrafluoroethylene (TFE) resin or the like. Various resin substrates can be used, such as those using hardened equipment and those using BT resin.

  The conductor of the land 6 is made of copper foil, but a metal layer may be formed on the copper foil. The plated layer 7 on the inner wall of the through hole 4 may be formed by electroless copper plating and electrolytic copper plating, and a metal layer may be formed on the surface of the plated layer 7. For example, the metal layer may include at least one selected from solder, gold, silver, nickel, palladium, and the like.

  As the adhesive agent 3, for example, at least one selected from an epoxy resin, a silicone resin, and a cyanate ester may be included. The epoxy resin may include at least one selected from, for example, bisphenol A type, bisphenol F type, biphenyl type, naphthalene type and the like.

  In addition to the resin component, the component of the adhesive 3 may include at least one selected from a filler, a flame retardant, a pigment, a curing agent, a curing accelerator, and the like. In addition to the above composition, a photoinitiator may be added.

  Hereinafter, a method of manufacturing the electronic device 10a according to the present embodiment will be briefly described with reference to FIGS. On the land 6 of the mounting substrate 1 shown in FIG. 6, for example, a solder paste is supplied by a printing method using a metal mask and a squeegee. Subsequently, the semiconductor device 2 is disposed on the land 6 of the mounting substrate 1, and the protruding electrode 5 and the land 6 of the semiconductor device 2 are soldered by reflow. As a result, the semiconductor device 2 can be mounted on the mounting substrate 1.

  Next, the adhesive 3 is applied to the side surface of the corner portion of the semiconductor device 2 shown in FIG. 7, the upper surface of the mounting substrate 1 in the corner portion of the semiconductor device mounting region, and the inside of the through hole 4 using a dispenser, for example.

  Finally, the semiconductor device 2 is bonded and fixed to the mounting substrate 1 by heating and curing up to a predetermined time at the curing temperature of the adhesive 3.

  By adopting such a manufacturing method, the electronic device 10a of the present embodiment has the adhesive substrate 3 at the two corners adjacent to each other in the corner portion of the semiconductor device 2 that is most easily peeled from the mounting substrate, and the mounting substrate 1 and Since the semiconductor device 2 mounted on the mounting substrate 1 is bonded and fixed to the through-hole 4, distortion in the mounting substrate 1 at the corner portion against an impact such as dropping is suppressed, and the mounting substrate 1 and the semiconductor device 2 are suppressed. It is possible to improve the impact strength of the solder at the joint with the protruding electrode.

  Hereinafter, the repair method of the electronic device 10a of the present embodiment will be described with reference to FIG. 8A to 8D are process cross-sectional views illustrating a process of removing the semiconductor device 2 in the repair work of the electronic device 10a according to the second embodiment of the present invention.

  FIG. 8A shows a state in which the failed semiconductor device 2 has an electronic device 10a bonded to the mounting substrate 1 with an adhesive 3 applied to the side surface of the corner portion and a drill 11 for excavation facing each other. Indicates. The outer diameter of the drill 11 for excavation is smaller than the inner diameter of the through hole 4 of the mounting substrate 1, and the drill 11 is provided with a stopper 12 having an outer diameter larger than the inner diameter of the through hole 4.

  FIG. 8B is a cross-sectional view in which the adhesive 3 in the through hole 4 is excavated from the back surface to the front surface of the mounting substrate 1 to a depth at which the stopper 12 of the drill 11 contacts the back surface of the mounting substrate 1.

  As described above, since the stopper 12 comes into contact with the mounting substrate 1, the drillable length of the drill 11 does not exceed the cross-sectional length of the mounting substrate 1. The configuration can be prevented.

  In FIG. 8C, after the adhesive 3 inside the through hole 4 is excavated and removed, the solder is bonded to the land 6 of the mounting substrate 1 and the protruding electrode 5 of the semiconductor device 2 and heated to a temperature at which the solder is melted. 1 is a cross-sectional view showing a state where a failed semiconductor device 2 is removed from 1. FIG.

  FIG. 8D is a cross-sectional view of the mounting substrate 1 after the semiconductor device 2 is removed.

  By adopting such a repair method, the electronic device 10a composed of the mounting substrate 1 and the BGA type semiconductor device 2 according to the present embodiment can be used even when the semiconductor device 2 is determined to be faulty by electrical inspection after mounting. The connecting portion between the mounting substrate 1 and the adhesive 3 is divided, and the semiconductor device 2 that has failed can be easily and cleanly removed from the mounting substrate 1.

  As a result, a new semiconductor device can be regenerated as the electronic device 10a bonded to the repaired mounting substrate by a simple repairing operation without discarding the mounting substrate 1, thereby greatly reducing the cost.

  Note that, when the semiconductor substrate 2 is bonded to the mounting substrate 1 on two adjacent surfaces of each corner portion as in the present embodiment, the number of bonding locations increases, so the semiconductor device 2 and the mounting substrate 1 While the adhesive force is improved, the degree of freedom of wiring on the mounting substrate 1 is reduced.

(Embodiment 3)
9 to 11 are diagrams showing the structure of the electronic device 20 according to the third embodiment of the present invention. FIG. 9 is a plan view, and FIG. 10 is the third and third embodiments in FIG. FIG. 11 is an enlarged plan view of another different structural example, and FIG. 11 is a cross-sectional view taken along 3A-3A in FIG. FIG. 9 shows a state in which a part of the semiconductor device 2 and the adhesive 3 is removed for easy understanding of the structure of the mounting substrate 1.

  The electronic device 20 according to the present embodiment is opposed to the semiconductor device 2, the mounting substrate 1 having the through holes 4 arranged in the corner portion of the semiconductor device mounting region, the side surface of the corner portion of the semiconductor device 2, and the semiconductor device 2. An adhesive 3 is provided for connecting and bonding the upper surface of the mounting substrate 1 located in the outer peripheral portion of the opening of the through hole 4 at the corner of the semiconductor device mounting region to the inside of the through hole 4.

  The semiconductor device 2 is a BGA type semiconductor device, and has a plurality of protruding electrodes 5 arranged in a grid pattern on one surface. In the semiconductor device 2 of the present embodiment, for example, a resin substrate, a ceramic substrate, or a flexible substrate may be used as an interposer, a semiconductor device called CSP (Chip Scale Package) may be used, and an electrode of a semiconductor element Alternatively, a flip chip type semiconductor element in which solder bumps are directly formed may be used.

  The protruding electrode 5 may be formed by a ball set method in which solder balls are mounted, or may be formed by supplying a solder paste by a printing method and performing reflow, or by a plating method. Furthermore, the material of the protruding electrode 5 may be at least one of a tin / zinc alloy, a tin / bismuth alloy, a tin / silver alloy, a zinc / bismuth alloy, gold, copper, It may be at least one of nickel, gold-plated nickel and gold-plated copper.

  When the mounting substrate 1 and the semiconductor device 2 are opposed to one surface of the base material, the mounting substrate 1 has conductor lands 6 disposed at positions corresponding to the protruding electrodes 5 included in the semiconductor device 2; A through-hole 4 is provided at a corner portion of the mounting area of the mounting substrate 1 on the semiconductor device.

  Further, the substrate of the mounting substrate 1 in the present embodiment is made of an epoxy resin, a polyimide resin, a polyamide resin, a polyester resin, a benzoxazal resin, ethylene tetrafluoride (TFE), or a fiber made of an organic substance such as glass fiber or Kepler. Various resin substrates such as those using a material impregnated with resin and cured and those using BT resin can be used.

  The conductor is made of copper foil, but a metal layer may be formed on the copper foil. For example, the metal layer may include at least one selected from solder, gold, silver, nickel, palladium, and the like.

  In the through holes 4 arranged at the respective corners on the mounting surface side of the semiconductor device 2, peeling pads 31 each having a weakly adhesive film with respect to the adhesive are arranged. For example, the film may be a film in which gold plating or aluminum plating is applied on the conductor foil surface, and may be, for example, a tetrafluoroethylene (TFE) resin film or a silicone resin film.

  The through hole 4 on the opposite side of the mounting surface is provided with a resin stopper pad 13 made of a conductive foil that covers the lower part of the through hole 4 and its periphery, and has an air hole 14 of a size that prevents liquid adhesive from leaking out at the center. ing. Note that the air hole 14 in the center of the resin stopper pad 13 is formed by the air under the adhesive 3 being discharged to the outside through the air hole 14 when the adhesive 3 is injected into the through hole 4. 4 is a hole for allowing the adhesive 3 to be poured up to the bottom of 4.

  Moreover, although the shape of the peeling pad 31 arrange | positioned at the corner part of the mounting area | region of the mounting board | substrate 1 is preferable circular, FIG. 12 which is a top view of the electronic device 20 and FIG. Such an L shape, or a cross shape, an ellipse shape or a polygon shape may be used.

  Further, the through holes 4 of the mounting substrate 1 for bonding and fixing the semiconductor device 2 are not only provided at each corner portion of the mounting region, but also each side of the semiconductor device 2 with the center point or center line of the mounting region symmetrical. A predetermined number may be provided.

  In addition, the position of the through hole 4 disposed on the outer periphery of the semiconductor device mounting region is not based on the position directly below the outer periphery of the semiconductor device, but based on the positional relationship between the side surface of the semiconductor device and the adhesive applied to the side surface of the semiconductor device. Further, the semiconductor device is spaced outward from the side surface of the semiconductor device by a dimension determined by the diameter of the through hole 4 or the dimension of the peeling pad 31.

  In addition, although the base material of the mounting substrate 1 is made of glass epoxy resin, for example, any of BT resin, polyimide resin, polyamide resin, polyester resin, benzoxazal resin, Teflon (registered trademark) resin, or paper epoxy resin is used. These may be a single layer or a laminate of these, or a laminate of a plurality of base materials, and may be a single layer or a laminate of any of aluminum oxide, aluminum nitride, glass, and quartz.

  The conductor is copper foil, but it may be laminated with any one of solder, gold, silver or palladium on the copper foil, for example, copper, solder, gold, silver or palladium on the nickel film One of them may be laminated. A transparent film such as tin chloride may be used for a transparent substrate such as glass or quartz.

  The adhesive 3 is used to stably fix the semiconductor device on the mounting substrate against external force, and is applied by connecting each corner portion side surface of the semiconductor device 2 and the through hole 4 of the mounting substrate 1, and heating. It is a member that is cured to bond and fix both.

  The composition is a thermosetting liquid resin composed of a main agent, a filler, a flame retardant, a pigment, a curing agent, a curing accelerator, and the like. For example, in addition to the above composition, a photo-curable liquid with a photoinitiator added Either a resin or a photothermographic liquid resin may be used.

  The material of the main resin of the adhesive 3 is an epoxy resin, but may be a resin obtained by synthesizing any one or a plurality of acrylic resins, polyimide resins, or silicone resins.

  With such a configuration, under the temperature at which normal equipment is used, the side surfaces of the corner portions of the semiconductor device 2 are bonded and fixed to the corresponding through-holes 4 of the mounting substrate 1 with the thermosetting adhesive 3. Thus, the semiconductor device 2 on the mounting substrate 1 is prevented from being distorted at the corner of the mounting substrate 1 against an impact such as dropping, and the impact strength of the solder at the joint between the mounting substrate 1 and the semiconductor device 2 is reduced. Can be improved.

  Further, in general, in an electronic device, when a liquid resin adhesive is applied to the side surface of the semiconductor device and the through hole of the mounting substrate, and the both are bonded by heat curing, the surface of the mounting substrate is flat. In addition, due to the good compatibility between them, the adhesive overflowing from the through hole of the mounting substrate spreads on the surface, and the adhesive remains attached to the surface of the mounting substrate during repair.

  However, in the electronic device 20 of the present embodiment, the mounting substrate 1 has a through hole 4 for bonding and fixing the semiconductor device 2, and the through hole 4 is gold-plated around, for example, the surface of a copper foil. A weakly adhesive peeling pad 31 is provided. In this way, when the gold thin film and the adhesive 3 are brought into contact with each other, gold does not oxidize and therefore has no bonding hand with the adhesive 3. Therefore, even if a physical bond (anchor effect or the like) is obtained for both, a chemical bond cannot be obtained, and a region where both are in contact is weakly bonded.

  In addition, as an example of the weakly adhesive release pad 31, the above description has been made with a structure in which the surface of the copper foil is gold-plated, but it is formed of a film of tetrafluoroethylene (TFE) resin or silicone resin. May be.

  Further, when the corner portion of the semiconductor device 2 and the through hole 4 of the mounting substrate 1 are bonded and fixed with the adhesive 3, the surface of the peeling pad 31 is made of a weak adhesive material such as gold, ethylene tetrafluoride (TFE), or silicone. By configuring, since the affinity between the liquid resin adhesive 3 and the peeling pad 31 is low, the surface tension of the adhesive 3 and the outer peripheral edge of the peeling pad 31 are stepped with respect to the base material surface of the mounting substrate 1. Due to the shape effect, the spread to the outside of the peeling pad 31 can be prevented.

  Then, the semiconductor device 2 and the mounting substrate 1 are bonded and fixed with an adhesive 3 at a plurality of locations including a corner portion of the semiconductor device 2 with a part of the side surface of the semiconductor device 2 and the wall surface of the through hole 4 of the mounting substrate 1. Therefore, the repairable mounting substrate 1 and the electronic device 20 using the same can be obtained by combining with the method described below.

  Here, the repair process of the electronic device 20 in this Embodiment is demonstrated using FIG.

  FIG. 14A to FIG. 14D are process cross-sectional views for explaining the repair process in the electronic device 20 of the present embodiment.

  FIG. 14A shows a resin formed so as to cover the through hole 4 on the back surface of the mounting substrate 1 in the electronic device 20 in which the BGA type semiconductor device 2 in which the protruding electrodes 5 are provided on the semiconductor device 2 is bonded to the mounting substrate 1. Sectional drawing which arranged both in the position where the center of the stop pad 13 and the center of the drill 15 for excavation provided with the stopper 16 with the same diameter as the through-hole 4 of the mounting board | substrate 1, and the stopper 16 oppose and correspond. It is.

  FIG. 14B shows the adhesive 3 in the through-hole 4 from the resin stop pad 13 side on the back surface of the mounting substrate 1 to the surface of the resin stop pad 13 by the stopper 16 of the drill 15. It is sectional drawing excavated to the depth which contacts.

  In FIG. 14C, after the adhesive 3 inside the through hole 4 is excavated and removed, the solder is bonded to the land 6 of the mounting substrate 1 and the protruding electrode 5 of the semiconductor device 2 and heated to a temperature at which the solder melts. 1 is a cross-sectional view of a failed semiconductor device 2 removed from 1. FIG.

  FIG. 14D is a cross-sectional view of the mounting substrate 1 after the semiconductor device 2 is removed.

  By adopting such a repair method, the electronic device 20 including the mounting substrate 1 and the BGA type semiconductor device 2 according to the present embodiment can be used even when the semiconductor device 2 is determined to be faulty by an electrical inspection after mounting. The connecting part between the mounting substrate 1 and the adhesive 3 is divided, and the interface between the two is completely peeled off when the solder joint is exposed to high temperature due to the difference in the linear expansion coefficient between the peeling pad 31 and the adhesive 3. Therefore, the failed semiconductor device 2 can be removed from the mounting substrate 1 easily and cleanly.

  Thereby, without discarding the mounting substrate 1 and the semiconductor device 2, a new semiconductor device can be regenerated as the electronic device 20 bonded to the repaired mounting substrate by a simple repair operation, so that a great cost reduction can be achieved.

  As described above, the stopper 16 comes into contact with the surface of the resin stop pad 13 so that the drillable length of the drill 11 does not exceed the cross-sectional length of the mounting substrate 1. It is possible to prevent damage to the parts.

  Further, in the repair work (not shown) of the electronic device 20 of the present embodiment, the failed semiconductor device 2 while melting the solder that joins the protruding electrode 5 of the semiconductor device 2 and the land 6 of the mounting substrate 1. Subsequent to the removal operation, a paste-like solder film is printed on the lands 6 of the mounting substrate 1.

  Then, the bump electrode 5 of the new semiconductor device 2 and the land 6 of the mounting substrate 1 are aligned, and the bump electrode 5 and the land 6 are joined by reflow. Finally, the repair is completed by connecting the corner side surface of the semiconductor device 2 and the through hole 4 of the mounting substrate 1 and applying the adhesive 3 and curing it.

  In order to remove the adhesive 3 from the mounting substrate 1, the resin stop pad 13 on the back surface of the mounting substrate 1 is broken with a drill 15, and the through-hole on the back side is used for use as the mounting substrate 1 for repair. A heat-resistant tape is bonded onto 4 or a lid made of a resin film is formed by a printing method.

  As a result, there is no step of scraping off the adhesive 3 with a knife or the like as in the prior art, and it is possible to significantly reduce man-hours and substrate disposal loss.

  In the above embodiment, the peeling pad 31 and the resin stopper pad 13 are provided on both surfaces of the through hole 4 formed in the mounting substrate 1. However, by using the high-viscosity adhesive 3, The mounting substrate 1 without the resin stop pad 13 may be used.

  This makes it possible to realize an electronic device that is even cheaper than the electronic device 20.

(Embodiment 4)
15 shows one of the mounting substrates 32 in the electronic device 21 in which the BGA type first semiconductor device 18 and the second semiconductor device 19 are mounted on both surfaces of the mounting substrate 32 according to the fourth embodiment of the present invention. FIG. 10 is a process cross-sectional view for explaining a repair process of the first semiconductor device 18 that is bonded to the surface and has failed.

  Hereinafter, with reference to FIG. 15A to FIG. 15E, the mounting substrate 32 of the present embodiment, the two types of BGA type first semiconductor devices 18 mounted on both surfaces of the mounting substrate 32, and A repair process in the electronic device 21 composed of the second semiconductor device 19 will be described.

  FIG. 15A shows an electronic device 21 in which the BGA type first semiconductor device 18 and the second semiconductor device 19 are both-side mounted on the mounting substrate 32, and the electronic device 21 in which the first semiconductor device 18 has failed. And the height of the drill 15 for drilling the adhesive 3 having the same diameter as or smaller than that of the through hole 4 on the side of the first semiconductor device 18 that is in failure, at a height that approaches the surface of the mounting substrate 32, 5 is a cross-sectional view arranged outside the peeling pad 41 of the mounting substrate 32. FIG.

  FIG. 15B shows the through hole 4 while horizontally moving the drill 15 from the outside of the peeling pad 41 of the failed first semiconductor device 18 toward the through hole 4 formed at the center of the peeling pad 41. It is sectional drawing which cut the adhesive agent 3 until it became the same position as a center position.

  In FIG. 15C, the adhesive 3 in the through hole 4 is excavated to a predetermined depth while the drill 15 that has moved horizontally and reached the through hole 4 of the peeling pad 41 is vertically lowered along the through hole 4. It is sectional drawing.

  The excavation depth is such that a slightly hardened layer of adhesive 3 remains on the bottom before the resin stop pad 13. This is an operation for preventing the adhesive 3 used for bonding the side surface of the semiconductor device 18 and the through-hole 4 at the center of the peeling pad 41 from flowing out to the back surface of the mounting substrate 32 during repair. The alignment of the drill 15 and the through hole 4 and the control of the drilling depth are performed by providing the resin drilling device provided with the drill 15 with NC control and laser height control functions.

  FIG. 15 (d) shows that the solder 3 joining the land 17 of the electronic device 21 from which the adhesive 3 inside the through-hole 4 of the mounting substrate 32 has been excavated and removed is heated to a temperature at which the solder melts, and a failure occurs. 2 is a cross-sectional view of the semiconductor device 18 of FIG.

  FIG. 15E is a cross-sectional view of the mounting substrate 32 after the failed first semiconductor device 18 is removed leaving the normal second semiconductor device 19.

  By using such a repair method, the connection portion between the first semiconductor device 18 and the mounting substrate 32 in the double-sided mounting type electronic device 21 can be divided.

  In the electronic device 21 in which the semiconductor device is mounted on both surfaces of the mounting substrate 32 with the through hole 4 and the adhesive 3, when both the first semiconductor device 18 and the second semiconductor device 19 are out of order. Then, the connecting portion between the first semiconductor device 18 and the second semiconductor device 19 and the mounting substrate 32 is divided by excavating and removing the adhesive 3 inside each through-hole 4 with a drill 15 from the mounting surface side of the small semiconductor device. it can.

  As a result, a clean and repaired mounting board 32 can be realized, and the process of scraping off the adhesive 3 with a knife or the like can be eliminated, thereby greatly reducing man-hours and board loss.

  Further, in the repair work (not shown) of the electronic device 21 of the present embodiment, the failed semiconductor device 18 while melting the solder that joins the protruding electrode 5 of the semiconductor device 18 and the land 17 of the mounting substrate 32 described above. And solder paste is applied to the lands 17.

  Then, the repaired mounting board 32 and the new semiconductor device are aligned, solder reflow is performed, and the new semiconductor device and the mounting board 32 are bonded and fixed. Finally, the adhesive 3 is applied to the side surface of the semiconductor device 18 where the respective peeling pads 41 are arranged and the inside of the through hole 4 and heat-cured to bond and fix both.

  By adopting such a repair method, the double-sided mounting type electronic device 21 composed of the mounting substrate 32 and the BGA type semiconductor device of the present embodiment determines that one of the semiconductor devices is defective in the electrical inspection after mounting. In this case, a new double-sided mounting type electronic device 21 can be obtained by performing a simple repair operation only on the failed first semiconductor device 18 without discarding the mounting substrate 32 and the second semiconductor device 19 without any failure. As a result, a great cost reduction can be realized.

  The electronic device and the method for repairing the electronic device according to the present invention are such that, in the normal device usage state of the electronic device, the end of the semiconductor device is adhesively fixed to the through hole of the mounting substrate with an adhesive that is thermally cured. In the semiconductor device mounted on the mounting substrate, distortion in the mounting substrate at the end portion against an impact such as dropping is suppressed, and the impact resistance strength of the solder can be improved.

  Also, when repairing, the adhesive inside the through-hole is excavated and removed with a drill for excavating the adhesive, and the semiconductor device can be easily removed from the mounting board by heating the solder to the melting temperature, which is efficient. Applicable to repair technology.

Plan view of the mounting board of the present invention 1A-1A sectional view of the mounting board in FIG. 1 is a plan view of an electronic device according to a first embodiment of the present invention. 1A-1A sectional view in FIG. 3 of the same embodiment Process sectional drawing which shows the repair method of the embodiment FIG. 3 is a plan view of an electronic device according to a second embodiment of the present invention. 2A-2A sectional view in FIG. 6 of the same embodiment Process sectional drawing which shows the repair method of the embodiment Plan view of an electronic apparatus according to a third embodiment of the present invention. 9 is an enlarged plan view of part 3B of FIG. 3A-3A sectional view in FIG. 9 of the same embodiment Plan view of an electronic apparatus according to a third embodiment of the present invention. The enlarged plan view in the 4A part of Drawing 12 of the embodiment Cross-sectional process diagram showing repair method for the same electronic device Process sectional drawing which shows the repair method of Embodiment 4 of this invention Schematic sectional view of a conventional electronic device Schematic sectional view showing a state where the mounting board of the electronic device is warped Schematic sectional view of another conventional electronic device Schematic sectional view of another conventional electronic device

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,32 Mounting board 2 Semiconductor device 3 Adhesive 4 Through-hole 5 Protruding electrode 6, 17 Land 7 Plating layer 10, 10a, 20, 21 Electronic device 11, 15 Drill 12, 16 Stopper 13 Resin stop pad 14 Air hole 18, 19 Semiconductor device 31, 41 Peel pad

Claims (6)

A semiconductor device comprising a plurality of protruding electrodes;
A mounting substrate having a plurality of lands corresponding to the plurality of protruding electrodes of the semiconductor device, and a through hole disposed in a part of an outer periphery of a land region in which the plurality of lands are disposed;
An adhesive for connecting and bonding a part of each of a pair of side surfaces facing each other in the semiconductor device and an inner peripheral portion of the through hole;
An electronic device comprising: The electronic device according to claim 1, wherein the bonding surface of the semiconductor device by the adhesive is two surfaces at a corner portion of the semiconductor device where the side surfaces adjacent to each other intersect. Around the opening of the through hole on the surface of the mounting substrate on which the plurality of protruding electrodes are mounted on the plurality of lands, the adhesive is weakly bonded to the inner periphery of the through hole. The electronic device according to claim 1, wherein a conductive layer is formed. It is a repair method of the electronic device of any one of Claims 1-3,
An electronic device repairing method comprising a cutting step of excavating the adhesive inside the through hole with a drill having an outer diameter equal to or smaller than the diameter of the through hole. The method for repairing an electronic device according to claim 4, wherein the drill includes a stopper that defines a thickness equal to or less than a thickness of the mounting substrate. A mounting substrate having a substrate for mounting a semiconductor device having a plurality of protruding electrodes,
A plurality of lands corresponding to the plurality of protruding substrates;
A mounting substrate comprising a through hole penetrating the substrate in a part of an outer periphery of a land region in which the plurality of lands are arranged.

Images