JP5604937B2 - Electronic component, electronic device and manufacturing method thereof - Google Patents

Description

  The present invention relates to an electronic component, an electronic device, and a manufacturing method thereof.

  Flip chip bonding is widely used for assembling electronic devices manufactured by assembling electronic components, for example, electronic devices using semiconductor elements or circuit boards. However, with the downsizing of electronic components, the gaps between the facing surfaces of the bonded electronic components are narrowed, and the arrangement pitch of bonding protruding electrodes is also narrowed. For this reason, it is difficult to inject an adhesive into the gap between electronic components after bonding.

  In order to eliminate such difficulty, a first underfill method is employed.

  FIG. 12 is a cross-sectional view of a conventional electronic component and electronic device, and represents an electronic component that is flip-chip bonded by the pre-underfill method and an electronic device that is assembled by flip-chip bonding of the pre-underfill method. 12A and 12B show a semiconductor element and a circuit board, respectively, and FIG. 12C shows an electronic device assembled using the semiconductor element and the circuit board.

  Referring to FIGS. 12A and 12B, a conventional semiconductor element 110 or circuit board 120 is formed of an adhesive 112 made of a thermosetting resin on substrates 111 and 121 on which semiconductor circuits and wirings are formed, respectively. , 122 are formed in the protruding electrodes 114 and 124 embedded in the periphery. The protruding electrodes 114 and 124 are formed on the substrates 111 and 121 through a seed layer made of a conductive thin film that is used as a seed for electroplating.

  Referring to FIG. 12C, the conventional electronic device 130 is manufactured by flip-chip bonding the semiconductor element 110 and the circuit board 120 with the tips of the protruding electrodes 114 and 124 being brought into contact with each other. At this time, the protruding electrodes 114 and 124 are joined by solid-phase diffusion or welding, and the adhesives 112 and 122 are heated and fused to be integrated at the time of bonding, and then thermally cured to become the adhesive 132.

  In the above-described first underfill type flip chip bonding, since the adhesives 112 and 122 are filled in advance between the protruding electrodes 114 and 124, gaps or protruding electrodes of electronic components (for example, the semiconductor element 110 and the circuit board 120) are used. Even if the pitch between 114 and 124 is narrow, the gap between the electronic components is reliably filled with the adhesive 132. Therefore, reliable flip chip bonding that does not generate voids in the gap is realized.

JP 2003-243502 A Japanese Patent Laid-Open No. 2001-68504

  As described above, in a conventional electronic device in which an adhesive is injected into a gap between bonded electronic components after bonding the protruding electrodes by flip chip bonding, an electronic component having protruding electrodes with a low height and a narrow pitch is used. When used, it is difficult to inject the adhesive between the protruding electrodes, and the gap between the joined electronic components is not completely filled with the adhesive, and a void may be generated, which reduces the reliability of the electronic device.

  The electronic device using the above-described underfill type electronic component in which the protruding electrode is embedded in advance with an adhesive as described above has high reliability because the space between the electronic components can be completely embedded with the adhesive. However, if this underfill type electronic component is used, connection failure between the protruding electrodes may occur as described below.

  FIG. 13 is a cross-sectional view for explaining a problem of the conventional electronic device, and represents a joint portion of the protruding electrode of the conventional electronic device 130 shown in FIG. 13A shows a cross section perpendicular to the bonding surface 136 of the bump electrode, and FIG. 13B shows a defect of the bonding surface 136 of the bump electrode by a cross section parallel to the bonding surface 136.

  Referring to FIG. 13, in the conventional electronic device 130, an insulating film 135 is formed on the bonding surface 136 of the protruding electrodes 114 and 124, which may cause a bonding failure between the protruding electrodes 114 and 124. The insulating film 135 is formed by the adhesive material heated and softened during the flip chip bonding entering the bonding surface 136 of the bump electrode and curing. Alternatively, it is also generated by forming a natural oxide film on the surface of the protruding electrode.

  An electronic device in which such an insulating film 135 is formed not only deteriorates electrical characteristics but also impairs flip chip bonding reliability.

  The present invention relates to an underfill type electronic component in which a protruding electrode for flip chip bonding is embedded with an adhesive, an electronic device using the electronic component, and a method for manufacturing the electronic component, and bonded by flip chip bonding. It is an object of the present invention to provide an electronic component, an electronic device, and a method of manufacturing the same that can prevent an insulating film from being formed on the joint surface of the protruding electrode.

  According to one aspect of the present invention for solving the above problems, according to one aspect of the present invention, a protruding electrode for flip chip bonding formed on a substrate, a recess formed on an upper surface of the protruding electrode, and the recess It is provided as an electronic component having an embedded flux and an adhesive that is formed on the substrate outside the protruding electrode and embeds the protruding electrode up to the upper surface of the protruding electrode.

  According to another aspect of the present invention, a flip-chip bonding protruding electrode formed on a substrate, and an adhesion formed on the substrate outside the protruding electrode and embedding the protruding electrode up to the upper surface of the protruding electrode. A first electronic component and a second electronic component having a material formed by joining the protruding electrodes to each other by flip chip bonding. At least one of the steps of preparing an electronic component having a recess filled with a flux on the upper surface of the protruding electrode, and then the first and second electronic components temporarily attached by abutting the protruding electrodes against each other In the decompression chamber, the step of gradually reducing the pressure in the decompression chamber, and the step of reducing the pressure. A step of raising the internal temperature to the bonding temperature, and before the temperature in the decompression chamber reaches the softening temperature of the adhesive, press the pressure to press the first and second electronic components up to the flip chip bonding pressure. And an applying step. The method is provided as a method for manufacturing an electronic device.

  According to the present invention, since the flux is filled in the recess that opens in the joint surface of the protruding electrode, the flux evaporates or sublimates by the heating during the flip chip bonding and penetrates into the joint surface. The natural oxide film formed in (5) is removed. Moreover, the penetration of the softened adhesive material into the joint surface is prevented by the vapor pressure of the flux. Therefore, formation of an insulating film on the bonding surface is prevented, and highly reliable flip chip bonding is realized.

Electronic component sectional view of a first embodiment of the present invention Projecting electrode plan view of the first embodiment of the present invention Electronic device sectional view of a 1st embodiment of the present invention Sectional drawing of the bump electrode connection part of 1st Embodiment of this invention Sectional drawing of the manufacturing process of the semiconductor element used in the first embodiment of the present invention. Manufacturing process sectional drawing of the circuit board of 1st Embodiment of this invention Manufacturing process sectional drawing of the electronic device of 1st Embodiment of this invention Manufacturing process sequence diagram of electronic device of first embodiment of the present invention Sectional drawing of semiconductor device of 2nd Embodiment of this invention Electronic device sectional view of a second embodiment of the present invention Electronic device sectional view of a third embodiment of the present invention Cross-sectional view of conventional electronic components and electronic equipment Sectional drawing for demonstrating the problem of the conventional electronic device

  1st Embodiment of this invention is related with the electronic device manufactured using the electronic component of this invention as a circuit board, and using the conventional electronic component as a semiconductor element.

  FIG. 1 is a cross-sectional view of the electronic component according to the first embodiment of the present invention, and shows the structure of the protruding electrode of the electronic component used in the first embodiment. Here, FIG. 1B is a circuit board 20 prepared as the first electronic component of the first embodiment, and FIG. 1A is a conventional first underfill prepared as the second electronic component. A semiconductor device 110 of the type is shown. FIG. 2 is a plan view of the bump electrode according to the first embodiment of the present invention, and shows the plane shape of the bump electrode of the circuit board 20.

  Referring to FIG. 1B, the circuit board 20 of the first embodiment uses, for example, a multilayer wiring board as the board 21, and the protruding electrode 24 connected to the wiring of the circuit board 20 is provided on the upper surface of the board 21. For example, they are arranged in a lattice pattern.

  The protruding electrode 24 is made of a conductive metal protrusion, and a flat surface necessary for flip chip bonding is formed on the upper surface thereof. The protruding electrode 24 may have a columnar shape, for example, a prismatic column shape or a columnar shape shown in FIGS. Furthermore, a ball bump whose upper surface is flattened may be used. The side and bottom surfaces of the protruding electrode 24 of the first embodiment are covered with a conductive metal seed layer 23 that serves as a seed for electrolytic plating. The seed layer 23 is manufactured by electrolytic plating. In the case of manufacturing the protruding electrode 24 having the depression 26 on the upper surface by another method, it can be omitted.

  A depression 26 is formed on the upper surface of the protruding electrode 24, and the depression 25 is filled with a flux 25. The flux 25 is evaporated or sublimated by heating at the time of flip chip bonding, and the natural oxide film formed on the surface of the bump electrode 24 is removed. Further, the flux 25 is preferably one that causes a curing reaction with the adhesive 22. By using a flux that causes a curing reaction, as described later, the evaporated or sublimated flux 25 oozes out into the adhesive 32 (see FIG. 3) in the vicinity of the bonding surface (the bonding region on the upper surface of the bump electrode 24). Then, the adhesive 32 is cured so as to surround the periphery of the joint surface. For this reason, the melted adhesive 32 is prevented from entering the joining surface.

  On the upper surface of the substrate 21 exposed around the protruding electrode 24, an adhesive 22 made of an insulating thermosetting resin is formed with a thickness substantially the same as the height of the protruding electrode 24. That is, the adhesive material 22 is substantially the same height as the protruding electrode 24 and embeds the outside of the protruding electrode 24 flatly. Therefore, the upper surface of the protruding electrode 24 and the upper surface of the adhesive 22 form a substantially flat surface.

  The second electronic component used in the first embodiment is the same as the conventional semiconductor element 110 described with reference to FIG. 12, and in order to simplify the description, the circuit board 20 according to the present invention described above will be described below. Only the differences are described.

  In the semiconductor element 110 (second electronic component) of the first embodiment, a semiconductor substrate 111 having a semiconductor integrated circuit formed on the main surface (the lower surface in FIG. 1A) is used as the substrate 111. On the main surface of the semiconductor substrate 111, a protruding electrode 114 manufactured by electrolytic plating through a seed layer 113 is formed. Usually, the seed layer 113 is not formed on the side surface of the protruding electrode 114. Note that when the protruding electrode 114 is manufactured by a method other than electrolytic plating, the seed layer may be omitted.

  The protruding electrode 114 has a flat surface on the upper surface, and is formed in, for example, a columnar shape or a ball bump shape having a flat upper surface, like the protruding electrode 24 of the circuit board 20 described above. Similarly to the circuit board 20, an adhesive 114 is provided on the substrate 111 exposed outside the protruding electrode 114 so as to bury the protruding electrode 114 up to the upper surface.

  However, unlike the protruding electrode 24 of the circuit board 20, a recess for filling the flux is not formed on the upper surface of the protruding electrode 114. In addition, it is preferable that the upper surface of the protruding electrode 114 is smaller than the protruding electrode 24 so that the entire upper surface (connection surface) of the protruding electrode 114 is bonded within the upper surface of the protruding electrode 24 of the circuit board 20.

  Hereinafter, the semiconductor element 110 (second electronic component) and the circuit board 20 (first electronic component) described above will be described in detail through their manufacturing processes.

  FIG. 5 is a cross-sectional view of a manufacturing process of a semiconductor device used in the first embodiment of the present invention, and shows a manufacturing process of a conventional underfill semiconductor device.

  The semiconductor element 10 of the first embodiment is manufactured in the same manner as a conventional pre-underfill semiconductor element. That is, referring to FIG. 5A, first, a seed layer 113 having a thickness of, for example, 200 nm in which a conductive thin film, for example, a Cu thin film is stacked on a Ti thin film, is formed on a semiconductor substrate 111 on which an integrated circuit is formed. For example, it is formed using sputtering.

  Next, a photosensitive resist 41 having a thickness of 10 to 15 μm, for example, is spin-coated on the entire surface of the seed layer 113. Thereafter, the resist 41 is exposed and developed to open openings 42 arranged in a lattice pattern in the resist 41. The openings 42 define the protruding electrodes 114, have a square pattern with a side length of 20 μm, for example, and are arranged in a grid pattern with a pitch interval of 50 μm, for example.

  Next, referring to FIG. 5B, with the seed layer 113 exposed on the bottom surface of the opening 42 formed in the resist 41 as a seed, a plating metal 114a made of a conductive metal, for example, Cu, is formed in the opening 42 by electrolytic plating. Form in.

  Next, referring to FIG. 5C, the resist 41 is removed, and the seed layer 113 exposed outside the plating metal 114a is etched and removed. Thereby, the plating metal 114a formed on the substrate 111 through the seed layer 113 is left in a lattice shape.

  Next, referring to FIG. 5D, an adhesive 112 that embeds and coats the plated metal 114a is applied to the entire surface of the substrate 111 by, for example, spin coating or printing. Then, pre-pacing was performed in an oven at 85 ° C. for 30 minutes, for example, so that the adhesive 112 was in a semi-cured state. As the adhesive 112, a thermosetting resin, for example, an epoxy-based sealing resin can be used. Moreover, you may use the insulating photosensitive thermosetting resin used as the adhesive material 22 of the circuit board 20, for example, an epoxy resin, a polyimide resin, or a benzocyclobutene. As described above, when the adhesives 112 and 22 of the semiconductor element 110 (second electronic component) and the circuit board 20 (first electronic component) are made of the same material, the adhesives 112 and 22 are easily and uniformly fused. Adhesion between the first and second electronic components is ensured.

  Next, the upper part of the adhesive 112 and the plated metal 114 a is removed from above the substrate 111 until the thickness of the adhesive 112 reaches the height of the projected electrode parallel to the upper surface of the substrate 111. Thereby, referring to FIG. 5E, the semiconductor element 110 including the protruding electrode 114 having a height of, for example, 5 to 7 μm, and the adhesive 112 filling the outer side thereof with substantially the same height (thickness) is obtained. Manufactured. The upper portions of the adhesive 112 and the plated metal 114a can be removed using, for example, a single crystal diamond tool.

  Next, a manufacturing process of the circuit board 20 (first electronic component) used in the first embodiment of the present invention will be described.

FIG. 6 is a cross-sectional view of the manufacturing process of the circuit board according to the first embodiment of the present invention, and shows the manufacturing process of the circuit board provided with the protruding electrode having the depression filled with the flux.
6A, in manufacturing the circuit board 20 of the first embodiment, first, an insulating photosensitive thermosetting resin such as epoxy, polyimide or benzocyclobutene is formed on the multilayer wiring board 21. For example, the adhesive 22 made of is spin-coated to a thickness of 10 to 15 μm. Thereafter, pre-baking is performed at 85 ° C. for 30 minutes to make the adhesive 22 semi-cured.

  Next, the adhesive 22 is exposed and developed, and an opening 42 that defines the protruding electrode 24 is formed in the adhesive 22. The openings 42 have a square pattern with a side length of 25 μm, for example, and are arranged in a lattice shape with a pitch interval of 50 μm, for example. The arrangement of the openings 42 was matched with the arrangement of the protruding electrodes 114 of the semiconductor element 110 described above. Further, the wiring in the substrate 21 is exposed on the bottom surface of the opening 42 (that is, the upper surface of the substrate 21).

  Next, referring to FIG. 6B, Ti and Cu are sequentially sputtered on the entire surface of the substrate 21 to cover the upper surface of the adhesive 22, the side surface of the opening 42, and the upper surface of the substrate 21 exposed on the bottom surface of the opening 42. For example, a seed layer 23 made of a Ti / Cu laminated film having a thickness of 200 nm is formed.

  Next, referring to FIG. 6C, a conductive metal, for example, a plated metal 24a of Cu is formed on the entire surface of the seed layer 23 by electrolytic plating using the seed layer 23 as a seed. The plated metal 24a is formed on the entire surface of the seed layer 23 with a substantially uniform thickness. Therefore, the plated metal 24a is formed on the side surface and the bottom surface of the opening 42 (through the thin seed layer 23) with a uniform thickness. As a result, the upper surface of the plated metal 24a at the center of the opening 42 is recessed and the depression 26 is formed. Is done. The size of the planar shape of the depression 26 can be controlled by the thickness of the plating metal 24a, and for example, the depression 26 is controlled to have a square planar shape with a side length of 3 to 5 μm.

  Next, referring to FIG. 6D, the flux 25 is filled in the depression 26 formed on the upper surface of the plating metal 24a using a dispenser. In the first embodiment, succinic anhydride is used as the flux 25. The dispenser heats succinic anhydride to its melting point of 120 ° C. and injects it into the depression 26 as a liquid. By using a dispenser, the flux 25 can be injected so as to rise in and around the recess 26, and the amount of the flux 25 used can be saved compared to spin coating. Of course, the flux 25 may be spin coated. The flux 25 injected into the depression 26 is solidified at room temperature.

  The flux 25 removes the natural oxide film formed on the surface of the plating metal 24a material, that is, the protruding electrode 24 material, and an appropriate flux 25 is selected according to the protruding electrode 24 material. Furthermore, the flux 25 is preferably chemically reacted with the adhesive 12 made of an epoxy resin of the semiconductor element 110 to cure the epoxy resin.

  As such a flux, an organic acid, an organic acid salt, an amine, an amine compound, a higher alcohol, or a synthetic rosin can be used, and an organic acid anhydride is preferable. For example, it is preferable to use a carboxylic acid anhydride such as succinic anhydride as the flux 25 for the Cu protruding electrode 24. The succinic anhydride has a function as a flux for removing natural oxide films of various metals and is cured by chemically reacting with the adhesive 12 made of an epoxy resin. In addition, succinic anhydride sublimes at the softening temperature of the epoxy resin. The reason why the physical properties of these succinic anhydrides are particularly suitable for use as the flux of the present invention will be described in detail in the manufacturing process of the electronic device 30 described later. In addition to succinic anhydride, a flux that removes the natural oxide film and accelerates the curing of the adhesive 12 can be used. An acid anhydride such as tetrahydrophthalic anhydride or hexahydrophthalic anhydride, or an amine compound can be used. Can be used.

  Next, referring to the one-dot chain line AB shown in FIG. 6D, the flux 25, the plating metal 24a, and the seed layer are set to have a height of 5 Remove to the position of the dot-dash line AB of ˜7 μm. The height of the removed surface (the height of the alternate long and short dash line AB) is set such that the flux 25 remains in the recess 26, in other words, the bottom of the recess 26 remains.

  As a result, referring to FIG. 6 (e), a protruding electrode 24 made of a plated metal 24a and having a height of 5 to 7 μm, an adhesive 22 for flatly embedding the protruding electrode 24, and a protruding electrode are formed on the substrate 21. The circuit board 20 according to the first embodiment of the present invention including the flux 26 filled in the depression 26 formed on the upper surface of the 24 is manufactured.

  Next, the electronic apparatus according to the first embodiment of the present invention will be described.

  FIG. 3 is a cross-sectional view of the electronic device according to the first embodiment of the present invention. The junction structure of the electronic device in which the conventional semiconductor element 110 is flip-chip bonded onto the circuit board 20 according to the first embodiment of the present invention described above. Represents.

  Referring to FIG. 3, the electronic device 30 according to the first embodiment of the present invention uses the circuit board 20 described above as the first electronic component, and flips the semiconductor element 110 described above as the second electronic component thereon. It is assembled by chip bonding.

  The circuit board 20 (first electronic component) and the semiconductor element 110 (second electronic component) are joined by abutting the tips of the protruding electrodes 24 and 114. The gap between the circuit board 20 and the substrates 21 and 111 of the semiconductor element 110 is filled with an adhesive 32 that fills the periphery of the protruding electrodes 24 and 114. The adhesive 32 is formed by fusing the adhesives 22 and 112 of the circuit board 20 and the semiconductor element 110.

  FIG. 4 is a cross-sectional view of the protruding electrode connection portion according to the first embodiment of the present invention, and represents a bonding portion of the protruding electrodes 24 and 114 of the electronic device 30 according to the first embodiment. 4A is a cross section perpendicular to the top surfaces of the substrate 21 and 111 of the bump electrode connecting portion, and FIG. 4B is a view of the bump electrode connecting portion viewed from the vertical direction of the top surface of the substrates 21 and 111. is there.

  4 (a) and 4 (b), in the electronic device 30 of the first embodiment, the solid state diffusion or the semiconductor element 110 and the protruding electrodes 114 and 24 of the circuit board 20 are in close contact with each other. Joined by welding. Since the leading end surface of the protruding electrode 114 of the semiconductor element 110 is larger than the leading end surface (upper surface) of the protruding electrode 24 of the circuit board 20, the bonded protruding electrodes 114 and 24 have a convex shape.

  The depression 26 provided on the upper surface of the protruding electrode 24 of the circuit board 20 becomes a cavity 26a by evaporating or sublimating the flux 25 filled in the depression 26 at the time of bonding. The curing reaction portion 31 is formed so as to surround the upper surface of the protruding electrode 24 of the circuit board 20 and the periphery of the protruding electrode 114 of the semiconductor element 110, that is, the periphery of the bonding surface, bonded to the upper surface. The curing reaction part 31 is formed by the flux 25 that has evaporated or sublimated oozes from the joint surface and undergoes a curing reaction with the adhesive 32. Note that when the flux 25 that does not undergo a curing reaction with the adhesive is used, the curing reaction portion 31 is naturally not formed.

  Hereinafter, the electronic device according to the first embodiment of the present invention will be described in more detail through the manufacturing process of the electronic device 30.

  FIG. 7 is a cross-sectional view of the manufacturing process of the electronic apparatus according to the first embodiment of the present invention, and represents a flip chip bonding process. FIG. 8 is a manufacturing process sequence diagram of the electronic device according to the first embodiment of the present invention, and shows a sequence of the bonding apparatus. Note that the temperature, pressure and pressure in FIG. 8 represent the temperature, pressure and pressure in the chamber, respectively.

  In the manufacturing process (assembly process) of the electronic device 30 according to the first embodiment of the present invention, referring to FIG. 7A, first, the above-described semiconductor is formed on the above-described circuit board 20 by using a flip chip bonding apparatus. The element 110 was positioned and placed so that the protruding electrode 24 and the protruding electrode 114 were in contact with each other, then heated to 100 ° C. and temporarily applied by applying a load of 1 gf per protruding electrode for 5 seconds.

  Next, referring to FIG. 7B, the temporary attachment body including the temporarily attached circuit board 20 and the semiconductor element 110 is accommodated in the decompression chamber 61. The chamber 61 includes a vacuum exhaust device connected to the exhaust port 62 in addition to a heating device and a pressurizing device necessary for flip chip bonding.

  Next, after the inside of the chamber 61 is replaced with a reducing gas of 1 atm, 3 gf of pressing 63 (pressure for pressing the semiconductor element 110 onto the circuit board 20) is applied to the protruding electrode that press-contacts the circuit board 20 and the semiconductor element 110. To do. At the same time, the inside of the chamber 61 starts to be evacuated, and the inside of the chamber 61 is heated to start raising the temperature.

  As a result, referring to FIG. 8, the pressure inside the chamber 61 is gradually reduced from the original 1 atm (760 Torr), and after 30 minutes, for example, reaches 0.1 Torr. The temperature in the chamber 61 is increased from the original room temperature (25 ° C.) at a constant rate, exceeds 100 ° C. after about 15 minutes, and reaches 200 ° C. after 30 minutes.

  Before the temperature in the chamber 61 reaches 100 ° C., for example, when 10 minutes have elapsed, the pressure 63 is increased to 10 gf per protruding electrode. Before this time, the temperature in the chamber 61 is 100 ° C. or lower, and the semi-cured adhesives 22 and 112 are not softened. Accordingly, the softened adhesive materials 22 and 112 do not enter between the protruding electrode 24 and the protruding electrode 114 before the pressure is increased.

  Next, referring to FIG. 7 (c) and FIG. 8, when the temperature exceeds 100 ° C. under reduced pressure after approximately 15 minutes, succinic anhydride of the flux 25 starts to sublime, and the vapor of the flux 25 is temporarily attached. Infiltrate the joint surfaces (temporary attachment surfaces) of the projected electrodes 24 and 114 formed. As the flux 25 evaporates or sublimates, a part of the recess 26 becomes a cavity 26a. Further, when the temperature exceeds 120 ° C., the semi-cured adhesives 22 and 112 are softened and melted. At this time, the gap between the joint surfaces (temporary attachment surfaces) is filled with the vapor of the flux 25 and is higher than the pressure in the chamber 61. Retained. For this reason, the penetration | invasion to the joint surface (temporary attachment surface) of the softened or fuse | melted adhesive materials 22 and 112 is blocked | prevented.

  Furthermore, with the passage of time, the vapor of the flux 25 that has infiltrated the joint surface (temporary attachment surface) exudes from the periphery of the joint surface and penetrates into the adhesive 112 near the joint surface (temporary attachment surface). A curing reaction portion 31 is formed around the joint surface (temporary attachment surface) by causing a chemical reaction and surrounding the outer periphery of the joint surface in an annular shape. The curing reaction part 31 prevents the softened and melted adhesive materials 22 and 112 from entering the joining surface (temporary attachment surface) from the outside of the joining surface (temporary attachment surface).

  As described above, in the manufacturing process by flip chip bonding of the electronic device 30 according to the first embodiment, even when the adhesives 22 and 112 are softened and melted, the vapor pressure of the flux 25 that fills the gap between the bonding surfaces is high. Since the curing reaction portion 31 is formed around the joint surface, the softened or melted adhesive materials 22 and 112 do not enter the joint surface.

  In addition, the vapor | steam of the flux 25 which infiltrated the joining surface (temporary attachment surface) removes the natural oxide film formed in the bump electrodes 24 and 114 surface of a joining surface like a normal flux. Therefore, no natural oxide film remains on the bonding surface.

  As described above, in the electronic device 30 of the first embodiment, the adhesive 32 does not enter the bonding surfaces (temporary bonding surfaces) of the protruding electrodes 24 and 114 and the natural oxide film is also removed. The insulating film 135 (see FIG. 13) made of an adhesive or a natural oxide film is not formed. For this reason, highly reliable flip chip bonding is realized.

  Next, referring to FIG. 7D and FIG. 8, when 30 minutes passed, the temperature and the atmospheric pressure in the chamber reached 200 ° C. and 0.1 Toor, respectively. Thereafter, the temperature and pressure in the chamber were maintained for 30 minutes. The pressure is maintained at 10 gf per protruding electrode.

  While being held at 200 ° C. for 30 minutes, the protruding electrode 24 and the protruding electrode 114 made of Cu are solid-phase diffused to each other through the bonding surface and firmly bonded. When the protruding electrodes 24 and 114 are made of a low melting point metal such as an Sn alloy, one or both of them are melted to form an alloy and are joined. The adhesive 112 and 22 of the semiconductor element 110 and the circuit board 20 are melted to become an integral adhesive 32 after the period of time elapses from the start of the temperature rise, and is then thermally cured. As described above, the adhesives 112 and 22 start to melt when the temperature in the chamber 61 reaches approximately 120 ° C. or higher, and the adhesive 32 is thermally cured while being held at 200 ° C. for 30 minutes. Through this process, the electronic device 30 of the first embodiment is manufactured.

  After the adhesive 32 is thermally cured, for example, when the elapsed time has passed 60 minutes, the heating in the chamber 61 is stopped and the temperature starts to drop. After reducing the temperature, for example, 10 minutes later, a reducing gas was introduced into the chamber to return the atmospheric pressure in the chamber to atmospheric pressure. Next, after cooling, for example, 45 minutes after the start of temperature drop, the pressing 63 was removed, and the electronic device 30 was taken out from the chamber 61.

  The second embodiment of the present invention relates to an electronic apparatus using the electronic component of the present invention as a semiconductor element and using a conventional electronic component as a circuit board.

  FIG. 9 is a cross-sectional view of an electronic component according to the second embodiment of the present invention. FIG. 9A shows the semiconductor element used in the second embodiment, and FIG. 9B shows the second embodiment. Represents a printed circuit board.

  Referring to FIG. 9A, the semiconductor element 10 of the second embodiment includes a protruding electrode 24 of the circuit board 20 of the first embodiment, instead of the protruding electrode 114 of the semiconductor element 110 of the first embodiment. The projection electrode 14 has a similar structure. Others are the same as those of the semiconductor element 110 of the first embodiment.

  That is, in the semiconductor element 10, an integrated circuit is formed, or protruding electrodes 14 are arranged in a lattice pattern on the upper surface of the semiconductor substrate 11, and an adhesive 12 that fills the outside of the protruding electrode 14 is formed on the semiconductor substrate 11. . The planar pattern of the protruding electrode 14 is the same size as the protruding electrode 114 of the semiconductor element 110 of the first embodiment. A recess 15 formed on the upper surface of the protruding electrode 14 is filled with a flux 15. In addition, seed layers 13 are provided on the side and bottom surfaces of the protruding electrodes 14. These are the same as the circuit board 20 of the first embodiment in both structure and material, except for the difference between the semiconductor substrate 11 and the wiring board 21 and the size of the protruding electrode 14.

  The semiconductor element 10 can be manufactured on the semiconductor substrate 11 in the same process as the circuit board 20 of the first embodiment described with reference to FIG.

  Referring to FIG. 9B, the circuit board of the second embodiment is a projection of the semiconductor element 110 of the first embodiment instead of the projection electrode 24 having the flux 25 of the circuit board 20 of the first embodiment. The protruding electrode 14 has the same structure as the electrode 114. Others are the same as the circuit board 20 of 1st Embodiment.

  That is, in the circuit board 120, the protruding electrodes 124 are arranged in a grid pattern on the upper surface of the wiring board 121, and the adhesive 112 that embeds the outside of the protruding electrodes 124 is formed on the wiring board 121. The planar pattern of the protruding electrode 124 is the same size as the protruding electrode 24 of the circuit board 20 of the first embodiment. A seed layer 123 is provided on the bottom surface of the protruding electrode 124. These are the same as the conventional circuit board 124 described with reference to FIG. 12 except for the difference between the wiring substrate 121 and the semiconductor substrate 121 and the size of the protruding electrode 124 in terms of structure and material.

  Such a circuit board 120 can be manufactured on the wiring board 121 in the same process as the semiconductor element 110 of the first embodiment described with reference to FIG.

  FIG. 10 is a cross-sectional view of an electronic device according to the second embodiment of the present invention, and represents an electronic device assembled by flip-chip bonding the semiconductor element 1 and the circuit board 120 shown in FIG.

  Referring to FIG. 10, in the electronic device 36 of the second embodiment, the flux 15 filled in the recess 16 formed at the tip end (lower end in FIG. 10) of the semiconductor element 10 is evaporated and sublimated. Thus, the cavity 16a is formed. On the other hand, the upper surface of the circuit board 120 is kept flat. Except for these points, the electronic device 36 of the second embodiment is the same as the electronic device 30 of the first embodiment.

  In other words, the protruding electrodes 14 and 124 of the semiconductor element 10 and the circuit board 120 are joined at their tips, and the gap between the semiconductor substrate 11 and the wiring board 121 is filled with the adhesive 32 formed by the fusion of the adhesives 12 and 122. Has been. A curing reaction portion 31 is formed around the joint surface of the projecting electrodes 14 and 124 joined. In addition, when using the flux which does not harden an adhesive material, this hardening reaction part 31 is not formed.

  The circuit board 121 can be manufactured on the semiconductor substrate 121 in the same process as the electronic device 30 of the first embodiment described with reference to FIG.

  The third embodiment of the present invention relates to an electronic apparatus using the electronic component of the present invention together with a semiconductor element and a circuit board.

  FIG. 11 is a cross-sectional view of an electronic apparatus according to a third embodiment of the present invention, and shows the structure of the connected protruding electrode.

  Referring to FIG. 11, the electronic device 37 according to the third embodiment of the present invention is assembled by connecting the circuit board 20 according to the first embodiment and the semiconductor element 10 according to the second embodiment by flip chip bonding.

  In the electronic device 37 of the third embodiment, the depressions 26 and 16 formed at the tips of the protruding electrodes 24 and 14 of both the circuit board 20 and the semiconductor element 10 are formed on the bonding surfaces of the protruding electrodes 24 and 14 as cavities 26a, 16a, and these cavities 26a and 16a are connected to form one cavity. Otherwise, the electronic device 37 of the third embodiment is the same as the electronic device of the first and second embodiments. The manufacture is also performed by the same flip chip bonding process as the electronic device 30 of the first embodiment.

By applying the present invention to an electronic device manufactured by flip chip bonding, an electronic device having a highly reliable connection structure in which the occurrence of insulation failure is suppressed is realized.

10, 110 Semiconductor element (electronic component)
11, 21, 111, 121 Substrate 20, 120 Circuit board (electronic component)
12, 22, 32, 112, 122, 132 Adhesive 13, 23, 113, 123 Seed layer 14, 24, 114, 124 Protruding electrode 24a, 114a Plating metal 15, 25 Flux 16, 26 Recess 16a, 26a Cavity 30, 36, 37, 130 Electronic equipment 31 Curing reaction part 41 Resist 42 Opening 61 Chamber 62 Exhaust port 63 Press 135 Insulating film 136 Joining surface

Claims (5)

A columnar protruding electrode formed on a substrate , wherein the conductive thin film metal disposed on the side and bottom surfaces of the protruding electrode and the conductive thin film metal are used as seeds to grow the conductive metal by electrolytic plating. A protruding electrode having a formed columnar conductive metal having a depression on the upper surface ;
And flux embedded in the previous Symbol recess,
An electronic component comprising: an adhesive formed on the substrate outside the protruding electrode and embedding the protruding electrode up to the upper surface of the protruding electrode.   The electronic component according to claim 1, wherein the flux causes a chemical reaction with the adhesive to cure the adhesive. A columnar impact force electrode formed on a substrate, wherein formed on said substrate outside of the bump electrode, a bonding material to embed the protruding electrode to the protruding electrode top surface, a first electronic component and the second having In an electronic device formed by joining the protruding electrodes to each other,
The protruding electrode of at least one of the first or second electronic component is formed of a conductive thin film metal disposed on a side surface and a bottom surface of the protruding electrode and a conductive metal by electrolytic plating using the conductive thin film metal as a seed. A columnar conductive metal object formed by growing
The adhesive filling between the first and second electronic components;
An electronic apparatus comprising: a curing reaction portion formed around the bonding surface of the protruding electrode and made of the adhesive material that is cured by causing a chemical reaction with the flux. Forming an insulating resist on the substrate;
Defining the protruding electrode in the resist and forming an opening on the bottom surface to expose the upper surface of the substrate;
Forming a seed layer made of a conductive thin film covering the upper surface of the resist, the side wall surface of the opening, and the bottom surface of the opening;
Forming a plating metal layer having a depression in the opening formed in a layer on the seed layer by electrolytic plating using the seed layer as a seed;
Filling the recess with flux;
Removing the flux, the plating metal, the seed layer, and the resist from the upper surface to the height of the protruding electrode in parallel with the upper surface of the substrate. 1st electronic component and 2nd electronic component which have the protruding electrode formed on the board | substrate, and the adhesive agent which is formed on the said board | substrate outside the said protruding electrode, and embeds the said protruding electrode to the said protruding electrode upper surface In a method for manufacturing an electronic device in which the protruding electrodes are joined to each other by flip chip bonding,
Preparing an electronic component having a recess filled with a flux on the upper surface of the protruding electrode as at least one of the first or second electronic component;
Next, accommodating the first and second electronic components temporarily attached by abutting each of the protruding electrodes in a decompression chamber;
Gradually reducing the pressure in the vacuum chamber;
Increasing the temperature in the decompression chamber to the bonding temperature during the decompressing step;
Applying a pressure for pressing the first and second electronic components to a flip-chip bonding pressure before the temperature in the decompression chamber reaches the softening temperature of the adhesive. Device manufacturing method.