JP2008288388A - Packaging method of electronic component, and manufacturing method of electronic component incorporated substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a packaging method of electronic components, along with a manufacturing method of an electronic component incorporated substrate, capable of surely fixing an electronic component by sufficiently enhancing adhesion strength of the electronic component to a base body, and surely realizing connection to a wiring even if the pitch between terminals of electronic component is made shorter. <P>SOLUTION: A conductor 12 of a sintered metal conductor being softer that a bump 32 of an electronic component 30 is formed by baking at a resin layer 11a to obtain a base body 10. The bump 32 of the electronic component 30 is positioned at a through hole in which the conductor 12 is embedded. Both are pressed so that the bump 32 is inserted into the through hole, causing a terminal surface of the electronic component 30 to abut against the resin layer 11a. Under such condition as the electronic component 30 is tightly secured to the resin layer 11a, the electronic component 30 is covered with a resin layer 40, and the resin layers 11a and 40 are hardened. Then, wirings 51 and 52 are formed and a passive component 60 is mounted to obtain the electronic component incorporated substrate 1. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for mounting an electronic component on a substrate, and a method for manufacturing an electronic component-embedded substrate in which the electronic component is embedded in an insulating layer.

  In recent years, for example, a semiconductor IC is mounted on a printed circuit board or the like in a bare chip (die) state in order to satisfy the demand for miniaturization and thinning of a module on which active components such as a semiconductor IC and passive components such as a capacitor are mounted. Technology is known. Such a bare-chip semiconductor IC has a very narrow electrode pitch compared to the semiconductor IC housed in the package. Therefore, when mounting this on a printed circuit board or the like, the electrode terminals provided on the semiconductor IC and the printed circuit An important issue is how to securely connect the wiring provided on the substrate.

  In such a module, as a method of connecting the terminals of the electronic component and the wiring, the electronic component is placed on the substrate with a so-called face-up so that the terminal surface (face) faces away from the substrate. A technology is known in which a resin layer covering an electronic component is formed and cured, a connection hole (via hole or contact hole) is formed in the resin layer to expose a terminal of the electronic component, and a wiring is formed so as to fill the connection hole. (See Patent Document 1).

As another method, for example, an electronic component is placed on a substrate (cured resin) on which wiring and connection points are formed, so that the terminal surface thereof faces the substrate side, so-called face-down. A method is also known in which a terminal of a component is brought into contact and a resin layer covering the electronic component is formed and cured (see Patent Document 2).
JP 2005-64470 A JP 2003-188538 A

  However, in the face-up method, the resin layer that covers the electronic component contracts during curing, so that the electronic component is inevitably displaced from the initial placement position. As a result, it becomes difficult to pattern and form a connection hole that reliably matches the position of the terminal of the electronic component embedded in the resin layer. Therefore, it is necessary to anticipate in advance the degree of positional displacement of the terminal due to the curing shrinkage of the resin layer, and to make a large connection hole that can expose the terminal even if there is such positional displacement. As a result, it becomes difficult to sufficiently cope with further narrowing of the pitch between terminals, and there is a possibility that it cannot sufficiently cope with further downsizing of the module in which the electronic component is built.

  On the other hand, in the face-down method, as described above, the electronic components are placed on the substrate on which wiring and connection points for connecting the electronic components are formed, so that the connection accuracy of the electronic components is higher than in the face-up method. . However, since the electrode terminal of the electronic component protrudes from the body surface of the electronic component, when the electronic component is placed on a substrate that has already been cured and a wiring pattern is formed, it is caused by the height of the terminal. As a result, a gap (gap) is formed between the substrate and the electronic component main body, and even if the electronic component is covered with the resin layer in this state, the void remains, so that the adhesion between the substrate and the electronic component is maintained. And the fixing of the electronic component on the board becomes unstable. Therefore, the face-down method generally tends to be inferior in the adhesive strength (mechanical connection strength) between the substrate and the electronic component as compared with the face-down method.

  Therefore, the present invention has been made in view of the above circumstances, and the object thereof is to sufficiently increase the adhesive strength of the electronic component to the substrate, thereby securely fixing the electronic component. Electrical connection reliability can be improved by suppressing misalignment, and even if the pitch between terminals of the electronic component is narrowed, the connection with the wiring can be realized reliably, so the electronic component is modularized An object of the present invention is to provide an electronic component mounting method and a method for manufacturing an electronic component-embedded substrate that can contribute to further miniaturization.

  In order to solve the above-described problem, an electronic component mounting method according to the present invention is a method for mounting an electronic component including a terminal on a base, the terminal embedded in a resin layer and a through-hole penetrating the resin layer. Forming a base including a softer conductor, and inserting a terminal of the electronic component into the through-hole and bringing the surface of the electronic component on the base into contact with the base. “Conductor” is “softer than the terminal” means that the degree of deformation of the conductor is larger than that of the terminal when the terminal and the conductor are pressed against each other and a load is applied (that is, pressed) to them. In addition to the hardness of the material itself, it indicates the softness in the structural strength of the “conductor” and “terminal”.

  In such a configuration, first, as a base, a resin layer and a conductor embedded in a through hole formed so as to penetrate the resin layer are formed, and a terminal of an electronic component is brought into contact with the conductor exposed from the resin layer. Position. When a predetermined load is applied to the electronic component in this state, since the conductor is softer than the terminal, the terminal of the electronic component is inserted into the through hole, and finally the surface of the electronic component body (the terminal is provided) Surface) and the substrate come into contact with each other, and as a result, the entire electronic component reliably contacts the resin layer. Therefore, the electronic component and the substrate are in close contact with each other, and the adhesive strength is improved. In addition, since the conductor formed in advance functions as a connection post (connection point), the positioning of the electronic component becomes extremely easy, and the electronic component is mounted on the base with high accuracy.

  Preferably, the step of forming the substrate further includes a step of forming a substrate including an uncured resin layer and curing the resin layer to fix the electronic component to the substrate. In this way, by curing the uncured resin layer in a state in which the electronic component is in contact, the adhesion strength of the electronic component to the substrate is further increased, and the positional deviation of the electronic component in the subsequent process and the cause thereof Thus, poor electrical connection of electronic components is prevented.

  More preferably, in the step of forming the substrate, a substrate including a sintered metal conductor having pores as a conductor is formed. In general, a sintered metal conductor obtained by firing a conductive paste containing a metal powder is a porous state in which a matrix of the conductive paste, for example, an organic vehicle is volatilized during firing and the metal powder is sintered, in other words, a large number of voids. Since it has a three-dimensional mesh-like structure (network) with holes formed, when the terminal of the electronic component is pressed against the conductor and a load is applied, the porous structure is deformed, The terminal of the electronic component is easily inserted into the through hole in which the conductor is embedded.

  Specifically, the step of forming the base includes a step of forming a through hole in the conductor forming sheet, a step of filling the through hole with a conductive paste, and a step of forming the conductor forming sheet filled with the conductive paste on the base substrate. Laminating the conductor forming sheet, firing the conductive paste into a sintered metal conductor, removing the fired conductor forming sheet from the base substrate, and sintering the metal on the base substrate. And a step of forming a resin layer so as to cover the conductor.

  At this time, it is useful to use a non-shrinkable sheet as the conductor forming sheet, and examples of the conductor forming sheet include a sheet made of a ceramic material having a sintering temperature higher than that of the conductor. As a result, even during firing to obtain a sintered metal conductor, the conductor forming sheet itself does not proceed with sintering, and therefore shrinkage hardly occurs. As a result, the displacement of the conductor is prevented, and the conductor is accurately transferred from the conductor forming sheet onto the base substrate.

  Furthermore, a method for manufacturing an electronic component built-in substrate according to the present invention includes an electronic component built-in substrate in which an electronic component including a terminal is disposed inside an insulating layer provided on a base using the electronic component mounting method according to the present invention. A method of manufacturing, a step of forming a base including a resin layer and a conductor embedded in a through hole penetrating the resin layer and softer than a terminal, and inserting a terminal of an electronic component into the through hole, A step of bringing the surface of the electronic component on the substrate side into contact with the substrate, and a step of forming an insulating layer on the substrate so as to cover the electronic component.

  According to this, the positioning accuracy when mounting the electronic component on the base is improved, and after the electronic component is securely fixed to the base, the insulating layer is formed and the electronic component is embedded, whereby the electronic component is mounted on the base. The electronic component built-in substrate with improved mechanical and electrical connection strength is manufactured. In particular, even when a resin layer is used as an insulating layer for covering an electronic component, the electronic component is bonded and fixed to the base before the electronic component is covered with the resin layer. This prevents the electronic components from being displaced.

  Preferably, the method further includes a step of polishing the upper surface of the insulating layer and the electronic component. In this way, it is possible to reduce the thickness and height of the electronic component, and thus the electronic component built-in substrate. In addition, since the electronic component is sufficiently bonded and fixed to the base body when polishing, the polishing of the electronic component is surely executed and the displacement of the electronic component at that time is also suppressed.

  Furthermore, it is more preferable to have a step of forming a wiring connected to the conductor exposed on the back surface of the substrate. Since the conductor is exposed on the back surface of the base body, the conductor also functions as a connection post (connection point) on the back surface, whereby the wiring can be reliably connected to the conductor. In addition, if the wiring and the terminal of the electronic component are formed of different materials, and the conductor (connectivity) between each of them and the conductor is superior to the connectivity between the wiring and the terminal, that is, By connecting the wiring and the terminal of the electronic component through such a conductor, an increase in electrical resistance at the connection site can be suppressed.

  Furthermore, the method includes a step of removing at least a part of the conductor exposed on the back surface of the substrate to expose the terminal of the electronic component, and a step of forming a wiring connected to the terminal of the electronic component exposed on the back surface of the substrate. Is also suitable. In this way, even if the electrical resistance of the conductor is larger than the electrical resistance of the terminal of the electronic component, the wiring is directly connected to the terminal of the electronic component, so the conductivity between the terminal and the wiring is more Enhanced.

  According to the electronic component mounting method and the electronic component-embedded substrate manufacturing method of the present invention, the electronic component main body is inserted by inserting the terminal of the electronic component into the through hole in which the conductor functioning as the connection post is embedded. Since it can be securely fixed by being in close contact with the base, it is possible to improve the electrical connection reliability by suppressing the displacement of the electronic component, and even if the pitch between the terminals of the electronic component is narrowed, The terminal and the wiring can be reliably connected, and this makes it possible to cope with further downsizing when the electronic component is modularized.

  Embodiments of the present invention will be described below with reference to the drawings. In the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted. Further, the positional relationship such as up, down, left and right is based on the positional relationship shown in the drawings unless otherwise specified. Furthermore, the dimensional ratios in the drawings are not limited to the illustrated ratios. Further, the following embodiments are exemplifications for explaining the present invention, and are not intended to limit the present invention only to the embodiments. Furthermore, the present invention can be variously modified without departing from the gist thereof.

  FIG. 1 is a schematic cross-sectional view showing the main part of the electronic component built-in substrate according to the present embodiment. The electronic component built-in substrate 1 has a resin layer 41 formed on one surface (the lower surface in the drawing) of the base 10, and the electronic component 30 is embedded inside the resin layer 41. A wiring 51 is formed on the other surface (the upper surface in the drawing) of the base 10, and the electronic component 30 disposed on one surface of the base 10 and the wiring disposed on the other surface of the base 10. 51 is electrically connected at the connection site 13.

  A wiring 52 is formed on the lower surface of the resin layer 41 in the figure (the surface opposite to the base 10), and the wiring 51 on the base 10 and the wiring 52 on the resin layer 41 penetrate the resin layer 41. It is electrically connected via the via 53. A resin layer 42 is formed on the surface of the resin layer 41 on the wiring 52 side, and a wiring 54 is formed on the surface of the resin layer 42. The wiring 54 and the wiring 52 are electrically connected via a via 55 that penetrates the resin layer 42.

  Further, a resin layer 43 is formed on the surface of the base 10 on the wiring 51 side, and a wiring 56 is formed on the surface of the resin layer 43. The wiring 56 and the wiring 51 are electrically connected through a via 57 that penetrates the resin layer 43, and a passive component 60 such as a resistor or a capacitor is installed in the wiring 56.

  Here, as a material used for the resin layers 41, 42, 43, specifically, for example, vinyl benzyl resin, polyvinyl benzyl ether compound resin, bismaleimide triazine resin (BT resin), polyphenyl ether (polyphenylene ether oxide) ) Resins (PPE, PPO), cyanate ester resins, epoxy + active ester cured resins, polyphenylene ether resins (polyphenylene oxide resins), curable polyolefin resins, benzocyclobutene resins, polyimide resins, aromatic polyester resins, aromatic liquid crystals Polyester resin, polyphenylene sulfide resin, polyetherimide resin, polyacrylate resin, polyetheretherketone resin, fluorine resin, epoxy resin, phenol resin or benzoxazine resin Single substance or these resins, silica, talc, calcium carbonate, magnesium carbonate, aluminum hydroxide, magnesium hydroxide, aluminum borate whisker, potassium titanate fiber, alumina, glass flake, glass fiber, tantalum nitride, aluminum nitride In addition, to these resins, at least one of magnesium, silicon, titanium, zinc, calcium, strontium, zirconium, tin, neodymium, samarium, aluminum, bismuth, lead, lanthanum, lithium and tantalum. Materials in which metal oxide powders containing metals are added, and further, materials in which resin fibers such as glass fibers and aramid fibers are blended with these resins, or glass resins, aramid fibers, nonwoven fabrics, and the like of these resins Impregnated materials, etc. It can, electrical properties, mechanical properties, water absorption, from the viewpoint of reflow resistance, can be appropriately selected.

  FIG. 2 is a perspective view schematically showing the structure of the electronic component 30. The electronic component 30 is a semiconductor device (electronic component) such as a semiconductor IC (die) in a bare chip state, and has a large number of land electrodes 31 on a main surface 30a having a substantially rectangular plate shape. In the figure, land electrodes 31 and bumps 32 (terminals) to be described later are displayed only at the four corners, and the display of other land electrodes 31 is omitted. Further, the type of the electronic component 30 is not particularly limited, and examples thereof include a digital IC having a very high operating frequency such as a CPU or a DSP.

  Further, although not particularly limited, the back surface 30b of the electronic component 30 is polished, and the thickness t (distance from the main surface 30a to the back surface 30b) of the electronic component 30 is thereby changed to a conventional semiconductor IC. For example, it is preferably 200 μm or less, more preferably about 20 to 50 μm. Further, the back surface 30b is preferably subjected to a roughening process such as etching, plasma processing, laser processing, blast polishing, buffing, chemical processing, etc. in order to make the electronic component 30 thin.

  In the present embodiment, as will be described later, the back surface 30b of the electronic component 30 can be polished after being separated into individual electronic components 30 by dicing. Note that a large number of electronic components may be polished together in the state of a wafer and then separated into individual electronic components 30 by dicing. Alternatively, a large number of electronic components may be polished in a wafer state and then separated into individual electronic components 30 by dicing, and then the individual electronic components may be polished to further reduce the thickness. .

  Each land electrode 31 is provided with a bump 32 (terminal) which is a kind of conductive protrusion. The type of the bump 32 is not particularly limited, and various bumps such as a stud bump, a plate bump, a plating bump, and a ball bump can be exemplified. In the drawing, a stud bump is illustrated. When stud bumps are used as the bumps 32, silver (Ag) or copper (Cu) can be formed by wire bonding, and when plate bumps are used, they can be formed by plating, sputtering or vapor deposition. . Further, in the case of using a plating bump, it can be formed by plating. In the case of using a ball bump, the solder ball is placed on the land electrode 31 and then melted or cream solder is applied to the land electrode. After printing on top, it can be formed by melting it. Further, it is also possible to use conical or columnar bumps obtained by screen printing a conductive material and curing it, or bumps obtained by printing nano paste and sintering it by heating.

  The metal species that can be used for the bump 32 are not particularly limited. For example, gold (Au), silver (Ag), copper (Cu), nickel (Ni), tin (Sn), chromium (Cr), nickel A chromium alloy, solder, etc. are mentioned, Among these, it is preferable to use copper. When copper is used as the material of the bump 32, for example, compared to the case where gold is used, it is possible to obtain a high bonding strength with respect to the land electrode 31, and the reliability of the electronic component 30 itself is enhanced.

  Further, the size and shape of the bumps 32 can be appropriately set according to the interval (pitch) between the land electrodes 31. For example, when the pitch of the land electrodes 31 is about 100 μm, the maximum diameter of the bumps 32 is set. What is necessary is just to make about 10-90 micrometers and height into about 2-100 micrometers. The bumps 32 can be cut and separated into individual electronic components 30 by wafer dicing and then bonded to the land electrodes 31 using a wire bonder.

  The electronic component 30 having such a configuration is arranged inside the resin layer 41 in a state where each bump 32 is electrically connected to the wiring 51 in the connection portion 13 (FIG. 1).

  FIG. 3 is a schematic cross-sectional view showing the configuration around the connection site 13. As shown in FIG. 1, the base 10 includes a resin layer 11 in which a connection hole (through hole) 14 is formed in a connection part 13 and a conductor 12 provided in the connection part 13 and exposed on both surfaces of the resin layer 11. The bump 32 is disposed so as to penetrate the conductor 12, and the tip end portion of the conductor 12 is directly connected to the wiring 51 in the connection hole 14.

  The resin layer 11 is made of a resin material, and the resin material is not particularly limited as long as it can be molded into a sheet shape or a film shape. For example, a thermosetting resin can be used. More specifically, epoxy resin, phenol resin, vinyl benzyl ether compound resin, bismaleimide triazine resin, cyanate ester resin, polyimide, polyolefin resin, polyester, polyphenylene oxide, liquid crystal polymer, silicone resin, fluorine resin, etc. These may be used alone or in combination of two or more. Further, it may be a rubber material such as acrylic rubber or ethylene acrylic rubber, or a resin material partially including a rubber component.

  The conductor 12 has a softer material or structure than the bump 32. As described above, when the bump 32 is pressed against the conductor 12 and pressed, the bump 32 is inserted into the connection hole 14 in which the conductor 12 is embedded. If it is soft as much as possible, the hardness of the material itself (generally measured values by various hardness tests, such as Brinell hardness, Bickers hardness, Rockwell hardness, etc.) is compared to the bump 32. And not limited to soft ones. In other words, it is only necessary that the bump 32 is inserted into the connection hole 14 when the bump 32 is pressed against the conductor 12.

As such a conductor 12, a porous thing is preferable, for example, the sintered metal conductor obtained by baking the electrically conductive paste containing metal powder can be used. Any metal material that can be used for the sintered metal conductor can be used as long as it is a sintered metal. For example, metals such as Ag, Pd, Au, Cu, and Ni, alloys, and the like can be used. . Moreover, the sintered metal conductor may contain, for example, 90% (mass basis) or more of the above metal, an oxide, and a glass component. Examples of the glass component include those containing as a main component at least one oxide selected from PbO, SiO ₂ , B ₂ O ₃ , ZnO, and alkaline earth metal oxides. However, oxides and glass components are not necessarily included.

  Next, an example of the manufacturing method of the electronic component built-in substrate 1 according to the present embodiment will be described with reference to FIGS. 4 to 20 (all are sectional views) together with the mounting method of the electronic component 30.

  First, as shown in FIG. 4, a conductor forming sheet 22 is formed on the support film 21. As the support film 21, for example, a sheet made of polyethylene terephthalate (PET) can be used. The conductor forming sheet 22 is used for the purpose of forming the conductor 12, and preferably has a non-shrinkable property at the time of firing for obtaining a sintered metal conductor. Examples of the conductor forming sheet include a sheet made of a ceramic material having a sintering temperature higher than that of the conductor. As a result, even during firing to obtain a sintered metal conductor, the conductor forming sheet itself does not proceed with sintering, and therefore shrinkage hardly occurs. More specifically, examples include aluminum oxide, zirconium oxide, calcium carbonate, quartz, mullite, cristobalite, and tridymite.

Among these, as the conductor forming sheet 22, a sheet using calcium carbonate (CaCO ₃ ) as a base material is preferably used. This is because the calcium carbonate material has a small shrinkage rate of several percent, and when moisture is absorbed after firing, it reacts with moisture and easily peels off. In addition, a sheet made of a material having a lower shrinkage rate may be fixed to the outside of the calcium carbonate. Thereby, the shrinkage | contraction rate of the sheet | seat 22 for conductor formation can be controlled, and the peelability can be improved. As such a sheet material, a tridymite material is preferable. Instead of the tridymite sheet, a sheet made of a material obtained by adding an alkaline earth metal (potassium, calcium, sodium, etc.) as a sintering aid to aluminum oxide may be fixed.

  Next, as shown in FIG. 5, a conductor-filling through hole 23 is formed in the laminate of the conductor-forming sheet 22 and the support film 21. The method for forming the through hole 23 is not particularly limited, and examples thereof include press working with a mold, punching processing, and laser processing. As a light source used for laser processing, for example, a carbon dioxide laser or a YAG laser can be used.

  Next, as shown in FIG. 6, a conductor precursor 24 is formed in the through hole 23. Examples of the method for forming the conductor precursor 24 include a method of filling the through holes 23 with a conductive paste by a screen printing method. The conductive paste constituting the conductor precursor 24 is prepared by kneading a conductive material made of various conductive metals or alloys such as Ag, Pd, Au, Cu, and Ni and an organic vehicle. The organic vehicle is mainly composed of a binder and a solvent, and the mixing ratio with the conductive material is arbitrary. Usually, the binder is 1 to 15% and the solvent is 10 to 50% on a mass basis. It mix | blends with an electrically-conductive material. Appropriate additives such as various dispersants and plasticizers may be added to the conductive paste as necessary.

  Next, as shown in FIG. 7, a sheet 22 for forming a conductor is laminated on an underlying substrate 20 such as alumina, zirconia, glass substrate, copper plate, copper foil, etc., which has a very low shrinkage. After pressing and pressure-bonding both, the support film 21 is peeled off.

  Furthermore, as shown in FIG. 8, the laminated body of the base substrate 20 and the conductor forming sheet 22 is fired. As the firing atmosphere, for example, an oxidizing atmosphere, a reducing atmosphere, or the like can be used. Specifically, air may be used. At the time of firing, since the sintering of the conductor forming sheet 22 itself does not proceed, the shrinkage hardly occurs. As a result, it is possible to prevent the displacement of the conductor.

  Also, by firing, the conductor precursor 24 held on the conductor forming sheet 22 adheres to the surface of the base substrate 20, and the sintering reaction of the metal in the conductor precursor 24 proceeds, so that the sintered metal conductor A conductor 12 made of is formed.

  Next, as shown in FIG. 9, the conductor forming sheet 22a is removed. At this time, when calcium carbonate is used as the base material of the conductor-forming sheet, the residue is removed by leaving it in a moisturizing atmosphere and removing the calcium carbonate, followed by ultrasonic cleaning. The conductor forming sheet 22 containing calcium carbonate is preferably used as the conductor forming sheet 22 because the operation of removing the fired product after firing is easy. Due to the non-shrinkage of the conductor forming sheet 22, the displacement of the conductor 12 due to the contraction of the sheet is suppressed, so that the conductor 12 is transferred from the conductor forming sheet 22 to the base substrate 20 with high positional accuracy.

  Then, as shown in FIG. 10, a resin layer 11 a is formed on the base substrate 20 so as to cover the conductor 12. As the resin layer 11a, a material that can realize high peel strength (peeling strength) with low roughness is preferable. As a method for forming the resin layer 11a, for example, a thermosetting resin sheet having a through hole at a position corresponding to the conductor 12 is laminated in a normal pressure or a vacuum (temporary pressure bonding), and then the resin is formed using an autoclave device. A method for improving the adhesion of the layer 11a is mentioned. Here, in the present embodiment, the resin layer 11a is in an uncured state (including a semi-cured state).

  Next, as shown in FIG. 11, the surface of the resin layer 11 a is removed to expose the conductor 12. The method for removing the resin layer 11a is not particularly limited, and examples thereof include polishing using a grinder, blasting, and irradiation with a carbon dioxide laser.

  Next, as shown in FIG. 12, the bumps 32 of the electronic component 30 and the conductor 12 of the resin layer 11a are aligned, and the electronic component 30 is placed face down on the resin layer 11a. At this time, since the conductor 12 exposed on the surface of the resin layer 11a can be used as a connection post, the alignment of the electronic component 30 becomes extremely easy. At this time, a load is applied to the electronic component 30 and the bumps 32 are inserted into the connection holes in which the conductors 12 are embedded, so that one surface of the electronic component 30 main body is brought into contact with the resin layer 11a.

  When the conductor 12 is a sintered metal conductor obtained by firing a conductive paste containing metal powder as described above, the organic vehicle that is the matrix of the conductive paste is volatilized during firing, so that the conductor 12 is porous and tertiary. It has an original mesh structure. Therefore, when the bump 32 of the electronic component 30 is pressed against the conductor 12, the bump 32 compresses and deforms the porous structure of the conductor 12, and is easily inserted into the through hole in which the conductor 12 is embedded. Thereby, both are closely fixed so that no gap is generated between the electronic component 30 and the resin layer 11a. Furthermore, the whole is heat-treated in that state, and is temporarily cured to such an extent that the resin layer 11a is not completely solidified.

  Next, as illustrated in FIG. 13, the resin layer 40 is formed on the resin layer 11 a so as to cover the electronic component 30. As the resin layer 40, a material that can realize high peel strength (peeling strength) with low roughness is preferable, as with the resin layer 11a. As a method for forming the resin layer 40, for example, a thermosetting resin sheet having an opening at a position corresponding to the electronic component 30 is laminated in a normal pressure or a vacuum (temporary pressure bonding), and then the resin is formed using an autoclave device. A method for increasing the adhesion of the layer 40 is exemplified. Subsequently, the whole is heat-treated in that state, and is temporarily cured to such an extent that the resin layer 40 is not completely solidified.

  Further, as shown in FIG. 14, the upper surface of the electronic component 30 together with the resin layer 40 is polished by, for example, a grinder or CMP to make the electronic component 30 thinner. At this time, since the electronic component 30 is tightly fixed to the resin layer 11a over the entire terminal surface, peeling of the electronic component 30 during polishing can be prevented.

  Next, as shown in FIG. 15, a resin layer 41 is formed on the surface of the base substrate 20 on the electronic component 30 side. As the resin layer 41, for example, a prepreg formed by impregnating a glass cloth 41a with a thermosetting resin is used. The presence of the glass cloth 41a can suppress the bending of the electronic component built-in substrate 1 after the support substrate 26 is peeled off. Then, the whole is subjected to a heat treatment, whereby the temporarily cured resin layers 11a and 40 and the uncured resin layer 41 are cured.

  Next, as shown in FIG. 16, the base substrate 20 is peeled off to expose the conductor 12 on the back surface (lower surface in the drawing) of the resin layer 11, and then the resin layer 11 and the conductor 12 are polished. Then, as shown in FIG. 17, wirings 51 connected to the bumps 32 of the electronic component 30 are formed on the resin layer 11. At this time, the wiring 52 is formed on the resin layer 41 at the same time before or after the formation of the wiring 51. 18 to 20 are diagrams showing details of a method of forming the wiring 51 on the resin layer 11.

  FIG. 18 shows an example of the state in which the conductor 12 is exposed on the surface of the resin layer 11 and the bump 32 is not exposed after the polishing, that is, the bump 32 does not penetrate the conductor 12. In this case, for example, as shown in FIG. 19, the surface layer portion of the conductor 12 is selectively etched to expose the bumps 32 in the connection holes 14, and then in the connection holes 14 as shown in FIG. In addition, the wiring 51 is formed on the resin layer 11, whereby the wiring 51 can be directly connected to the bump 32 at the connection portion 13.

  Thus, the form in which the wiring 51 is directly connected to the bump 32 is effective when the electrical connection resistance between the bump 32 and the wiring 51 is smaller than the connection resistance between the conductor 12 and the wiring 51. For example, when the conductor 12 is a sintered metal conductor, the porous structure of the conductor 12 is compressed by the insertion of the bumps 32 and the gap is reduced, but the connection resistance with the wiring 51 is increased by the presence of the remaining gap. It is assumed that this will happen.

  Here, the wiring 51 can be patterned by, for example, a semi-additive method. In the semi-additive method, after a base layer is formed on the entire surface of the resin layer 11 including the connection portion 13, the base layer remaining or exposed on the pattern is selectively removed or masked except for the wiring pattern portion of the base layer. A wiring 51 is formed by depositing a metal layer thereon. Alternatively, the wiring 51 may be patterned by a subtractive method, that is, after a metal layer is formed on the entire surface of the resin layer 11 including the connection portion 13, the metal layer is etched. At that time, the electroless plating method is preferably used for forming the metal layer, but a PDV method such as sputtering or vapor deposition, or a CVD method can also be used. The method for forming the wiring 52 is the same as that for the wiring 51.

  Further, as shown in FIGS. 21 and 22, the wiring 51 may be formed on the resin layer 11. 21 and 22 are cross-sectional views of the main part showing another state in which the wiring 51 is formed at the connection site 13. In this example, as shown in FIG. 21, the bump 32 is exposed from the resin layer 11 by polishing the resin layer 11 and the conductor 12.

  In the drawing, the upper end portion of the bump 32 is deformed to be wide. For example, the height (length) of the bump 32 is larger than the thickness of the resin layer 11a in FIG. When 32 is pressed while penetrating the conductor 12 and in contact with the base substrate 20 made of alumina or the like, the contact portion at the tip thereof can be compressed and deformed. Then, after the surfaces of the bumps 32 and the conductors 12 are cleaned by blasting, desmearing, etc., as shown in FIG. 22, the wirings 51 electrically connected to the bumps 32 and the conductors 12 are formed in the same manner as described above. Can do.

  After forming the wiring 51 as described above, a general process, for example, a resin layer forming process of laminating a resin layer with or without copper foil, a via hole is formed in the resin layer, and the via hole is embedded. By repeatedly performing the wiring formation process of patterning the vias and wiring and mounting the passive component 60, the electronic component built-in substrate 1 shown in FIG. 1 can be obtained.

  According to the method of manufacturing an electronic component built-in substrate using the electronic component mounting method according to the present invention configured as described above, after the conductor 12 softer than the bump 32 of the electronic component 30 is formed with high positional accuracy, the conductor The electronic component 30 is placed using 12 as a connection post. At this time, the bump 32 of the electronic component 30 is inserted into the connection hole (through-hole) 14 in which the conductor 12 is embedded, and the terminal surface of the electronic component 30 is brought into contact with the resin layer 11a. 30 is securely fixed to the resin layer 11a having adhesiveness, whereby the adhesive strength between the electronic component 30 and the base 10 can be remarkably increased, and the electronic component 30 is prevented from being displaced and electrically Connection reliability can be improved.

  Further, since the conductor 12 formed in advance functions as a connection post, the positioning of the electronic component 30 becomes extremely easy. Therefore, even if the pitch between the bumps 32 of the electronic component 30 is narrowed, the bump 32 and the wiring 51 can be reliably connected. As a result, the electronic component built-in substrate 1 on which the electronic component 30 is mounted on the module can be further connected. It becomes possible to cope with downsizing.

  Further, when a sintered metal conductor is used as the conductor 12, the position accuracy of the conductor 12 can be sufficiently increased by adopting the non-shrinkable conductor forming sheet 22. Therefore, the positioning accuracy of the electronic component 30 can be further improved, and the connection reliability of the electronic component 30 can be further increased. Furthermore, since the sintered metal conductor is porous and the bumps 32 can be easily inserted due to its three-dimensional structure, the electronic component 30 and the base body 10 can be more closely adhered to each other.

  Furthermore, since the electronic component 30 can be realized in such a state that the electronic component 30 is tightly fixed to the base body 10, it is possible to prevent positional displacement when the electronic component 30 is polished and thinned together with the resin layer 40. 30 and the electronic component built-in substrate 1 can be reduced in size and height without impairing the reliability.

  In addition, as above-mentioned, this invention is not limited to said embodiment, A various deformation | transformation is possible in the limit which does not deviate from the summary. For example, an electronic component 30 that does not have the bump 32 but is provided with only the land electrode 31 or the same type of electrode structure may be used. In this case, the land electrode 31 or the same type of electrode structure corresponds to a “terminal”. Further, as the conductor 12, a conductive paste may be used. Furthermore, the conductor 12 may not be covered with the resin layer 11a as shown in FIG. 10, and the state of FIG. 10 may be omitted and the resin layer 11a may be built up to the state of FIG. Furthermore, the glass cloth 41a is not always necessary. Furthermore, when the connection resistance between the conductor 12 and the wiring 51 is sufficiently low, the wiring 51 may be formed without etching the conductor 12. In addition, the electronic component built-in substrate 1 may be modularized by opposingly arranging (stacking) the multi-stage (two or more stages). The electronic component 30 is not limited to an active component such as a semiconductor IC, and may be a passive component such as a capacitor. Further, the resin layer 11a and the resin layer 40 may be temporarily cured at the same time.

  As described above, according to the method for mounting an electronic component and the method for manufacturing a semiconductor-embedded substrate according to the present invention, the electronic component can be securely fixed by sufficiently increasing the adhesive strength of the electronic component to the base. It is possible to improve the electrical connection reliability by suppressing the displacement of the electronic component, and to contribute to further miniaturization when the electronic component is modularized. Therefore, active components such as semiconductor devices and / or It can be widely and effectively used for the manufacture of devices, apparatuses, systems, various devices, etc. that incorporate passive components such as resistors and capacitors, especially those that require miniaturization and high performance.

It is a schematic sectional drawing which shows the principal part of the electronic component built-in substrate which concerns on this embodiment. 2 is a perspective view schematically showing a structure of an electronic component 30. FIG. It is a schematic sectional drawing which shows the structure of the periphery of the connection site | part 13 of wiring and an electronic component. It is process drawing which shows an example of the procedure which manufactures an electronic component built-in board | substrate. It is process drawing which shows an example of the procedure which manufactures an electronic component built-in board | substrate. It is process drawing which shows an example of the procedure which manufactures an electronic component built-in board | substrate. It is process drawing which shows an example of the procedure which manufactures an electronic component built-in board | substrate. It is process drawing which shows an example of the procedure which manufactures an electronic component built-in board | substrate. It is process drawing which shows an example of the procedure which manufactures an electronic component built-in board | substrate. It is process drawing which shows an example of the procedure which manufactures an electronic component built-in board | substrate. It is process drawing which shows an example of the procedure which manufactures an electronic component built-in board | substrate. It is process drawing which shows an example of the procedure which manufactures an electronic component built-in board | substrate. It is process drawing which shows an example of the procedure which manufactures an electronic component built-in board | substrate. It is process drawing which shows an example of the procedure which manufactures an electronic component built-in board | substrate. It is process drawing which shows an example of the procedure which manufactures an electronic component built-in board | substrate. It is process drawing which shows an example of the procedure which manufactures an electronic component built-in board | substrate. It is process drawing which shows an example of the procedure which manufactures an electronic component built-in board | substrate. It is process drawing which shows an example of the procedure which manufactures an electronic component built-in board | substrate. It is process drawing which shows an example of the procedure which manufactures an electronic component built-in board | substrate. It is process drawing which shows an example of the procedure which manufactures an electronic component built-in board | substrate. It is process drawing which shows the other example of the procedure which manufactures an electronic component built-in board | substrate. It is process drawing which shows the other example of the procedure which manufactures an electronic component built-in board | substrate.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Electronic component built-in substrate, 10 ... Base | substrate, 11, 11a ... Resin layer, 12 ... Conductor, 13 ... Connection part, 14 ... Connection hole, 20 ... Base substrate, 21 ... Support film, 22, 22a ... Sheet for conductor formation , 23 through-holes, 24 conductor conductors, 25 adhesive layers, 26 support substrates, 30 electronic components, 30a main surfaces, 30b back surfaces, 31 land electrodes, 32 bumps (terminals), 40 41, 42, 43 ... resin layer, 41a ... glass cloth, 51, 52, 54, 56 ... wiring, 53, 55, 57 ... via, 60 ... passive component.

Claims (9)

A method of mounting an electronic component having a terminal on a substrate,
Forming the base body comprising a resin layer and a conductor softer than the terminal embedded in a through-hole penetrating the resin layer;
Inserting the terminal of the electronic component into the through-hole and bringing the base-side surface of the electronic component into contact with the base; and
A method of mounting an electronic component having In the step of forming the substrate, the substrate is provided with an uncured resin layer,
Curing the resin layer and fixing the electronic component to the substrate;
The electronic component mounting method according to claim 1. In the step of forming the base, the base is provided with a sintered metal conductor having pores as the conductor.
The electronic component mounting method according to claim 1. The step of forming the substrate includes
Forming a through hole in the conductor forming sheet;
Filling the through hole with a conductive paste;
Laminating the sheet for forming a conductor filled with the conductive paste on a base substrate;
Firing the conductor-forming sheet and using the conductive paste as a sintered metal conductor;
Removing the fired product of the conductor-forming sheet from the base substrate;
Forming the resin layer to cover the sintered metal conductor on the base substrate;
The electronic component mounting method according to claim 1, further comprising: As the conductor-forming sheet, a non-shrinkable material is used.
The electronic component mounting method according to claim 4. A method of manufacturing an electronic component-embedded substrate in which an electronic component having a terminal is disposed inside an insulating layer provided on a substrate,
Forming the base body comprising a resin layer and a conductor softer than the terminal embedded in a through-hole penetrating the resin layer;
Inserting the terminal of the electronic component into the through-hole and bringing the base-side surface of the electronic component into contact with the base;
Forming an insulating layer on the substrate to cover the electronic component;
The manufacturing method of the electronic component built-in board | substrate which has this. Polishing the upper surface of the insulating layer and the electronic component;
The manufacturing method of the electronic component built-in substrate according to claim 6. Forming a wiring connected to the conductor exposed on the back surface of the substrate;
The manufacturing method of the electronic component built-in substrate according to claim 6. Removing at least a portion of the conductor exposed on the back surface of the base to expose the terminal of the electronic component;
Forming a wiring connected to the terminal exposed on the back surface of the substrate;
The manufacturing method of the electronic component built-in board | substrate of Claim 6 which has these.

Images