JP2007180166A - Electronic component, manufacturing method thereof, circuit board, and electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic component capable of uniformizing the amount of collapse of a bump electrode. <P>SOLUTION: The electronic component 121 includes on an active surface 121a an electrode 24 and a bump electrode 10 connected electrically with the electrode 24 for electrical connection with a partner board via the bump electrode 10. The electronic component further includes on the active surface 121a a gap control layer 15 provided for keeping an interval between the active surface 121a and the partner side board unchanged. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

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

  Flip chip mounting is known as a method for mounting an electronic component such as a semiconductor IC on a substrate mounted on various electronic devices. In this flip chip mounting, for example, a bump electrode (metal bump electrode) such as an Au plating bump is formed on the lower surface of an electronic component, and the bump electrode is crushed and brought into contact with the terminal electrode on the substrate. Connection is made. Recently, a resin bump electrode having a resin protrusion as a core has been developed as a bump electrode. If this resin bump electrode is used, the impact at the time of mounting and crimping is absorbed by the resin core portion, so that a structure with higher connection reliability can be obtained.

  By the way, when mounting an electronic component on a substrate, it is common to first place an adhesive resin such as ACF or NCF on the mounting surface of the substrate, and press the electronic component on the substrate in such a manner as to push it apart. Is. The adhesive pushed away by the electronic component is discharged from the gap between the bump electrodes to the outside of the electronic component, and finally only the adhesive layer having a necessary thickness is disposed between the electronic component and the substrate.

  However, when mounting is performed through the adhesive as described above, the amount of collapse of the bump electrode may vary between the end and the center of the electronic component. One of the causes is that the adhesive for bonding the substrate and the electronic component tends to flow out at the end of the electronic component, but difficult to flow out at the center of the electronic component. It is considered that the pressure becomes non-uniform. In other words, if there is a distribution in the pressure of the adhesive, the electronic components are inclined obliquely, thereby causing variations in the degree of collapse of the bump electrodes.

Therefore, in order to solve this problem, it is considered to adopt the method disclosed in Patent Document 1. That is, the dummy bump electrodes are uniformly provided on the lower surface of the electronic component. According to this method, by providing a dummy bump electrode that does not participate in electrical connection on the lower surface of the electronic component, variation in the arrangement of the bump electrode can be improved, and the flow of the adhesive can be made uniform when mounting and crimping the electronic component. Be expected.
JP-A-9-68715

  However, in the above method, only uniform bump electrode deformation is considered when a uniform distribution of pressure is applied to the electronic component, and the case where a different distribution of pressure is applied to the electronic component is handled. I can't. That is, if the pressure acting on the electronic component is distributed, the flow of the adhesive and the crushing state of the bump electrode become non-uniform, and a sufficient effect cannot be obtained. In particular, in a resin bump electrode having a resin material as a core, the bump electrode itself is easily deformed. Therefore, variation in contact resistance due to non-uniformity of the bump electrode crushing is larger than that of the metal bump electrode, and electro-optics When it is applied to an apparatus, there is a possibility that it becomes impossible to sufficiently cope with high definition due to the rounding of electric signals generated thereby.

  The present invention has been made in view of such circumstances, and provides an electronic component capable of making the amount of collapse of the bump electrode uniform when mounting the electronic component on a substrate, and a method for manufacturing the same. Objective. It is another object of the present invention to provide a circuit board and an electronic device that are provided with such electronic components and have improved connection reliability.

In order to solve the above problems, an electronic component according to the present invention has an electrode on an active surface and a bump electrode electrically connected to the electrode, and is electrically connected to the counterpart substrate via the bump electrode. Electronically connected electronic components, characterized in that a gap control layer is provided on the active surface to maintain a constant distance between the active surface and the counterpart substrate.
According to this configuration, since the gap (gap) between the electronic component and the counterpart substrate can be uniformly maintained at the thickness of the gap control layer, the bump electrode is uniformly crushed across the entire active surface, and the bump electrodes are A uniform characteristic with no variation in contact resistance or the like can be obtained.

In the present invention, the bump electrode includes a resin protrusion protruding from the electrode, and a conductive film disposed from the surface of the electrode to the surface of the protrusion, and is disposed on the surface of the protrusion. It is desirable to be electrically connected to the counterpart substrate through the conductive film provided.
According to this configuration, since the bump electrode is a resin material core (resin bump electrode), when the bump electrode is pressed against the terminal of the mating substrate, the resin protrusion is elastically deformed, and the mating side The warp of the substrate can be absorbed. In addition, since the bump electrode is elastically deformed and contacts the counterpart substrate, the conductive contact state via the bump electrode is maintained even if the adhesive that bonds them thermally expands due to a temperature change. Further, it is only necessary to pattern a thin metal film as compared with a core (metal bump electrode) having a metal material such as an Au-plated bump. Therefore, the aspect ratio of the resist for etching can be reduced. A gap (narrow pitch) can be achieved.

In the present invention, it is desirable that the gap control layer and the protrusion are made of the same material.
According to this configuration, the gap control layer and the bump electrode can be formed in a common process, and the manufacturing process is simplified.

In the present invention, it is preferable that the gap control layer is provided in substantially all regions of the active surface except for regions where the bump electrodes are disposed. Here, “substantially all” includes not only a case where the gap control layer is provided in all regions other than the bump electrodes, but also a region where the gap control layer is not partially formed within a range in which gap control is not hindered. The purpose is to include cases.
According to this configuration, since the gap control layer is formed in a wide area, the gap control layer is not easily deformed when the electronic component is pressed on the counterpart substrate, and good gap control is possible over the entire active surface. become.

In the present invention, it is preferable that a groove extending from the center of the gap control layer to the outer periphery of the gap control layer is provided on the surface of the gap control layer.
If the groove is formed in this way, when the electronic component and the counterpart substrate are bonded by the adhesive, the adhesive can escape, and the excess adhesive is interposed between the gap control layer and the counterpart substrate. Will not be placed. For this reason, the pressure distribution of the adhesive becomes uniform in the active surface, and thereby a more uniform collapse amount of the bump electrode can be obtained.

In the present invention, it is desirable that the surface of the gap control layer is provided with irregularities.
According to this configuration, since the surface area of the gap control layer is increased by the fine irregularities provided on the surface of the gap control layer, the adhesion with the counterpart substrate can be improved.

The electronic component manufacturing method of the present invention includes an electrode, a resin protrusion protruding from the electrode, and a conductive film disposed from the surface of the electrode to the surface of the protrusion on the active surface. A method of manufacturing an electronic component that is electrically connected to a counterpart substrate via the conductive film disposed on the surface of the protrusion, wherein a resin film having a certain thickness is formed on the active surface A step of patterning the resin film to form the projection and a gap control layer having the same thickness as the projection, and a step of forming the conductive film from the surface of the electrode to the surface of the projection. And a step of reducing the thickness of the gap control layer to the same thickness as the thickness of the gap to be held between the active surface and the counterpart substrate.
According to this method, it is possible to manufacture an electronic component that has high connection reliability and can cope with a narrow gap of the bump electrode. In this method, since the gap control layer and the bump electrode are formed in a common process, the manufacturing becomes easier as compared with the case where they are formed separately.

In the present invention, it is preferable that the step of reducing the thickness of the gap control layer is performed by plasma processing the surface of the gap control layer.
According to this method, since fine irregularities are formed on the surface of the gap control layer by the plasma treatment, the surface area of the gap control layer is widened by the irregularities, and the adhesion with the counterpart substrate can be improved.

In the present invention, it is desirable to form a groove on the surface of the gap control layer when patterning the resin film.
If the groove is formed in this way, when the electronic component and the counterpart substrate are bonded by the adhesive, the adhesive can escape, and the excess adhesive is interposed between the gap control layer and the counterpart substrate. Will not be placed. For this reason, the pressure distribution of the adhesive becomes uniform in the active surface, and thereby a more uniform collapse amount of the bump electrode can be obtained. Further, since the groove is formed at the same time when the resin film is patterned, a new process is not added and the process is simplified.

The circuit board of the present invention is a circuit board having a substrate and an electronic component electrically connected to the substrate, wherein the electronic component includes the electronic component of the present invention described above. . The circuit board of the present invention is a circuit board having a substrate and an electronic component electrically connected to the substrate, and the electronic component has an electrode on the active surface, and an electrical connection with the electrode. A bump electrode connected to the substrate, and is electrically connected to the substrate via the bump electrode. Between the substrate and the active surface of the electronic component, the substrate and the active surface A gap control layer that keeps the distance constant is provided.
According to these structures, since the gap (gap) between the electronic component and the counterpart substrate can be kept uniformly in the thickness of the gap control layer, the bump electrode is uniformly crushed across the entire active surface. Uniform characteristics with no variation in contact resistance between them can be obtained.
In this configuration, the gap control layer may be disposed on either the electronic component side or the substrate side on which the electronic component is mounted. Further, a member having such a function as a gap control layer may be disposed in an adhesive that bonds them. In this case, such a member or an adhesive layer mixed with the member is the gap control layer of the present invention. As such a member, a spacer for gap control generally used in a liquid crystal display device or the like can be used.

In the present invention, it is desirable that the substrate and the electronic component are bonded via an adhesive.
According to this structure, the connection state of an electronic component and a board | substrate can be firmly fixed with an adhesive agent. When an adhesive is placed between the electronic component and the substrate, non-uniformity in the amount (pressure) of the adhesive tends to occur between the end and the center of the active surface due to the difference in discharging properties. In the circuit board of the present invention, the gap control layer keeps the distance between the active surface and the opposite substrate constant, so that the pressure distribution is less likely to be non-uniform than the conventional circuit board. The amount of crushing can be obtained.

An electronic apparatus according to the present invention includes the above-described circuit board according to the present invention.
According to this configuration, it is possible to provide an electronic device having high connection reliability and excellent electrical characteristics.

  Embodiments of the present invention will be described below with reference to the drawings. In the following drawings, the ratio of dimensions between components may be different from the actual one.

[Electro-optical device]
FIG. 1 is a schematic view showing a liquid crystal display device which is an embodiment of an electro-optical device.
The illustrated liquid crystal display device 100 includes a liquid crystal panel 110 and a semiconductor device 121. Moreover, incidental members, such as a polarizing plate, a reflective sheet, and a backlight (not shown), are appropriately provided as necessary.

  The liquid crystal panel 110 includes substrates 111 and 112 made of glass or plastic. The substrate (circuit substrate) 111 and the substrate 112 are arranged to face each other and are bonded to each other by a sealing material (not shown). A liquid crystal (not shown) that is an electro-optical material is sealed between the substrate 111 and the substrate 112. An electrode 111a made of a transparent conductor such as ITO (Indium Tin Oxide) is formed on the inner surface of the substrate 111, and an electrode 112a disposed opposite to the electrode 111a is formed on the inner surface of the substrate 112. . The electrode 111a and the electrode 112a are arranged so as to be orthogonal to each other. Then, the electrode 111a and the electrode 112a are drawn out to the substrate extension portion 111T, and an electrode terminal 111bx and an electrode terminal 111cx are formed at the end portions, respectively. An input wiring 111d is formed in the vicinity of the edge of the substrate overhanging portion 111T, and a terminal 111dx is also formed at the inner end thereof.

  A semiconductor device (electronic component) 121 is mounted on the substrate extension portion 111T via a sealing resin (adhesive) 122. The semiconductor device 121 is, for example, a liquid crystal driving IC chip that drives the liquid crystal panel 110. A large number of bump electrodes (not shown) are formed on the lower surface of the semiconductor device 121, and these bump electrodes are electrically connected to terminals 111bx, 111cx, 111dx on the substrate overhanging portion 111T, respectively.

  A flexible wiring board 123 is mounted on the input terminal 111dy formed at the outer end of the input wiring 111d via an anisotropic conductive film 124. The input terminals 111dy are conductively connected to wirings (not shown) provided on the flexible wiring board 123, respectively. Then, a control signal, a video signal, a power supply potential, and the like are supplied from the outside to the input terminal 111 dy through the flexible wiring board 123, and a drive signal for driving the liquid crystal is generated in the semiconductor device 121 and supplied to the liquid crystal panel 110. It is like that.

  According to the liquid crystal display device 100 of the present embodiment configured as described above, an appropriate voltage is applied between the electrode 111a and the electrode 112a via the semiconductor device 121, whereby the electrodes 111a and 112a are Light can be modulated by re-orienting the liquid crystal of the pixel portions opposed to each other, whereby a desired image can be formed in the display area in which the pixels in the liquid crystal panel 110 are arranged.

  FIG. 2 is a side cross-sectional view taken along the line HH in FIG. 1, and is an explanatory diagram of a mounting structure of the semiconductor device 121 in the liquid crystal display device 100. As shown in FIG. 2, a plurality of bump electrodes 10 are provided as IC side terminals on the active surface (the lower surface in the drawing) of the semiconductor device 121, and the tips thereof are in direct conductive contact with the terminals 111 bx and 111 dx of the substrate 111. Yes. The periphery of the conductive contact portion between the bump electrode 10 and the terminals 111bx and 111dx is filled with a cured sealing resin 122 made of a thermosetting resin or the like. In addition, a gap (gap) between the mounting surface 111A and the active surface 121a is constant between the active surface 121a of the semiconductor device 121 and the surface 111A (mounting surface) of the substrate 111 on which the semiconductor device 121 is mounted. A gap control layer 15 is provided. The gap between the semiconductor device 121 and the substrate 111 and the gap control layer 15 are held constant over the entire active surface, so that the amount of collapse of the bump electrode 10 pressed against the terminals 111bx and 111dx becomes uniform. ing.

[Semiconductor device]
Next, a terminal structure of the semiconductor device 121 will be described. FIG. 3 is a partial perspective view showing the structure on the active surface side of the semiconductor device 121 where the terminals are formed.
The semiconductor device 121 is, for example, an IC chip that drives a pixel of a liquid crystal display device, and an electronic circuit (integrated circuit) such as a plurality of electronic elements such as thin film transistors and wirings connecting the electronic elements is provided on the active surface side. It is formed (both not shown).

  In the semiconductor device 121 shown in FIG. 3, a plurality of electrode pads (electrodes) 24 are arranged along the long side of the active surface 121a. The electrode pad 24 is drawn from the above-described electronic element or the like, and functions as an external electrode of the electronic circuit. In addition, a resin protrusion (hereinafter referred to as a resin protrusion) 12 that is linearly continuous along the electrode pad row 24a is formed inside the electrode pad row 24a on the active surface 121a. Further, a plurality of conductive films 20 are formed as metal wirings connecting the electrode pads 24 and the tops of the resin protrusions 12 from the surface of each electrode pad 24 to the surface of the resin protrusion 12. The bump electrode 10 is configured to include the resin protrusion 12 as a core and the conductive films 20 disposed on the surface of the resin protrusion 12.

  The conductive films 20 are arranged at a constant pitch according to the arrangement of the electrode pads 24. The resin protrusion 12 is exposed at a portion where the conductive film 20 is not disposed, and the surface of the exposed resin protrusion 12A is shaved by plasma treatment to reduce its thickness.

  In the example of FIG. 3, the resin protrusion 12 is disposed inside the electrode pad row 24a, but the resin protrusion 12 may be disposed outside the electrode pad row 24a.

  A gap control layer 15 is provided at the center of the active surface 121a. The gap control layer 15 is sandwiched between the semiconductor device 121 and the counterpart substrate 11 when the semiconductor device 121 is mounted on the counterpart substrate 11, and keeps a gap (gap) between them at a constant interval. In the case of this embodiment, the gap control layer 15 is configured as a flat film having a certain thickness. The gap control layer 15 is formed so as to cover almost the entire inner side of the bump electrode 15 from the vicinity of the bump electrode 15 to the central portion of the active surface 121a.

4A and 4B are diagrams showing the configuration of the main part of the bump electrode 10, FIG. 4A is an enlarged plan view of the periphery of the bump electrode, and FIG. 4B is a side view taken along line AA in FIG. It is sectional drawing.
As shown in FIG. 4, a plurality of electrode pads 24 made of a conductive material such as Al are arranged on the periphery of the active surface 121 a of the semiconductor device 121. Further, a passivation film 26 as a protective film made of an electrically insulating material such as SiN is formed on the entire active surface of the semiconductor device 121, and an opening 26a of the passivation film 26 is formed on the surface of each electrode pad 24 described above. Is formed.

  Resin protrusions 12 are formed on the surface of the passivation film 26 and inside the electrode pad row 24a. The resin protrusion 12 is formed to project from the active surface 121a of the semiconductor device 121, extends linearly at substantially the same height, and is disposed in parallel with the electrode pad row 24a. The resin protrusion 12 is made of an elastic resin material such as polyimide resin, acrylic resin, phenol resin, epoxy resin, silicone resin, or modified polyimide resin. The cross-sectional shape of the resin protrusion 12 is desirably a shape that can be easily elastically deformed, such as a semicircular shape or a trapezoidal shape as shown in FIG. By doing so, the bump electrode 10 can be easily elastically deformed at the time of contact with the counterpart substrate, and the reliability of the conductive connection with the counterpart substrate can be improved.

  The resin protrusion 12 is preferably formed of a photosensitive resin. In this case, the resin protrusion 12 is formed by coating a photosensitive resin on the surface of the passivation film 26 and performing photolithography. As a result, the resin protrusion 12 can be accurately arranged inside the electrode pad row 24 a on the active surface 121 a of the semiconductor device 121. Note that by performing photolithography using a gray mask, the cross section of the resin protrusion 12 can be formed into a tapered shape that can be easily elastically deformed, such as a trapezoidal shape or a semicircular shape.

  A plurality of conductive films 20 are formed as metal wirings connecting the electrode pads 24 and the tops of the resin protrusions 12 from the surface of each electrode pad 24 to the surface of the resin protrusion 12. The conductive film 20 is made of a conductive material such as Au, Ag, TiW, Cu, Ni, Pd, Al, Cr, Ti, W, NiV, or lead-free solder. The conductive film 20 may have a two-layer structure such as TiW / Au. The conductive film 20 can be formed by, for example, forming a conductive metal such as Ai, Cu, or Ni on the entire active surface of the semiconductor device 121 by vapor deposition or sputtering, and performing an appropriate patterning process thereon. In addition, the surface of the underlying conductive film made of Cu, Ni, Al or the like can be further covered with Au plating or the like to improve the conductive contact property.

  The conductive film 20 extends from the electrode pad 24 to the opposite side across the resin protrusion 12 and is in close contact with the active surface 121a on the opposite side. That is, the conductive film 20 is in close contact with the surface of each electrode pad 24 on the outer side of the resin protrusion 12, and is formed through the surface of the resin protrusion 12 to the active surface 121 a on the inner side of the resin protrusion 12. A close contact surface is formed with the passivation film 26 disposed on the active surface 121a. For this reason, since the conductive film 20 is fixed to the active surface on both sides of the resin protrusion 12, the conductive film 20 has a structure in which peeling or the like hardly occurs when the conductive film 20 is bonded to the counterpart substrate. The shape of the conductive film 20 is not limited to this, and can be deformed. The conductive film 20 may be formed at least between the electrode pad 24 and the top of the resin protrusion 12.

  A gap control layer 15 is provided on the surface of the passivation film 26 and inside the bump electrode 10. The gap control layer 15 is formed to protrude from the active surface 121a of the semiconductor device 121, and covers the entire central portion of the active surface 121a at substantially the same height. The gap control layer 15 is made of a resin material having elasticity such as polyimide resin, acrylic resin, phenol resin, epoxy resin, silicone resin, and modified polyimide resin. In the present embodiment, the gap control layer 15 and the resin protrusion 12 are made of the same material.

  The surface of the gap control layer 15 is shaved by plasma treatment, and the thickness thereof is thinner than the thickness of the resin protrusion 12B where the conductive film 20 is disposed. In the present embodiment, for example, the thickness h1 of the resin protrusion 12B is about 15 μm, and the thickness h2 of the gap control layer 15 is about 10 μm. Further, the surface of the gap control layer 15 is roughened by this plasma treatment, and a large number of fine irregularities are formed on the surface. This unevenness has the effect of increasing the surface area of the gap control layer 15, that is, the contact area when coming into contact with the counterpart substrate 11, and this makes it possible to obtain high adhesion with the counterpart substrate. It has become.

  Note that the resin protrusion 12 </ b> A in the portion where the conductive film 20 shown in FIG. 3 is not disposed is shaved by plasma treatment simultaneously with the gap control layer 15, so that the thickness thereof is the same as the gap control layer 15. Further, the surface of the resin protrusion 12A is roughened by this plasma treatment, and a large number of fine irregularities are formed on the surface.

  As shown in FIG. 1, the bump electrode 10 is thermocompression bonded to the terminal 111 bx on the substrate 111 through the sealing resin 122. The sealing resin 122 is a thermosetting resin, and is in an uncured state or a semi-cured state before mounting. If the sealing resin 122 is in an uncured state, it may be applied to the active surface (the lower surface in the drawing) of the semiconductor device 121 or the surface of the substrate 111 before mounting, and if the sealing resin 122 is in a semi-cured state, What is necessary is just to insert between the semiconductor device 121 and the board | substrate 111 as a film form or a sheet form. An epoxy resin is generally used as the sealing resin 122, but other resins may be used as long as they can achieve the same purpose.

[Method of mounting semiconductor device]
FIG. 5 is an enlarged view of a main part showing a method of mounting the semiconductor device 121 on the terminal 111 dx of the substrate 111. FIG. 5A shows a state in which the semiconductor device 121 is pressed to bring the tip of the bump electrode 10 into contact with the terminal 111dx of the substrate 111. FIG. 5B further presses the semiconductor device 121. The bump electrode 10 is elastically deformed. FIG. 5C is an enlarged view of a contact portion between the gap control layer 15 and the substrate 111 in FIG.

  As shown in FIG. 5A, when mounting the semiconductor device 121, first, the sealing resin 122 is disposed on the mounting surface 111 </ b> A of the substrate 111. As the sealing resin 122, for example, a thermosetting adhesive such as NCF (Non Conductive Film) is preferably used. The sealing resin 122 is generally thicker than the bump electrode 10 formed on the semiconductor device 121. The sealing resin 122 is provided in a larger area than the active surface 121a of the semiconductor device 121, so that the semiconductor device 121 can be reliably mounted on the substrate 111. The sealing resin 122 may be disposed on the active surface 121a of the semiconductor device 121 instead of being disposed on the mounting surface 111A of the substrate 111.

  Next, the semiconductor device 121 is disposed on the mounting surface 111A of the substrate 111, and the semiconductor device 121 is pressure-bonded onto the mounting surface 111A in a state where the bump electrode 10 and the terminal 111dx are aligned. The device 121 is mounted.

  The semiconductor device 121 is mounted by applying pressure while heating the semiconductor device 121 on the substrate 111 using a heating and pressing head (not shown) or the like. At this time, the sealing resin 122 is initially softened by heating, and the top of the bump electrode 10 is in conductive contact with the terminal 111bx so as to push the softened resin apart (FIG. 5A). In this case, since the thickness of the bump electrode 10 is thicker than the thickness of the gap control layer 15, the surface 15 A of the gap control layer 15 is still in contact with the substrate 111 when the tip of the bump electrode 10 contacts the substrate 111. Not.

  As shown in FIG. 5B, when the semiconductor device 121 is further pressurized in this state, the resin protrusion 12 that is the core of the bump electrode 10 is pressed and elastically deformed in the contact direction (the vertical direction in the drawing). When the bump electrode 10 is crushed to some extent, the gap control layer 15 comes into contact with the mounting surface 111A of the substrate 111, and the semiconductor device 121 is not pushed further into the substrate 111 side. Here, since the gap control layer 15 is formed so as to cover the entire active surface, the distance between the active surface 121a and the mounting surface 111A can be controlled approximately accurately by the thickness of the gap control layer 15. . Therefore, even if the semiconductor device 121 is not pressed with a uniform pressure distribution, the active surface 121a and the mounting surface 111A can be held in a substantially parallel state, and as a result, the amount of collapse of the bump electrode 10 can be reduced. It can be uniform across the active surface. Furthermore, since the amount of crushing of the bump electrode 10 is controlled by the thickness of the gap control layer 15, the bump electrode 10 is excessively crushed even if the force to pressurize the semiconductor device 121 is strong, and the conductive film 20 is broken or peeled off. There is no problem such as. Therefore, in the liquid crystal display device 100 including such a gap control layer 15, the bump electrode 10 is uniformly crushed, so that the contact resistance and the like of the bump electrode 10 can be made uniform and the bump electrode 10 can be made uniform. By restricting the crushing amount within a certain range, the connection reliability of the bump electrode 10 is also improved.

  Although not shown, in the mounting process of the semiconductor device 121, the gap between the semiconductor device 121 and the substrate 111 is maintained not only by the gap control layer 15 but also by the resin protrusion 12A provided between the bump electrodes. Is done. That is, when the bump electrode 10 is crushed to some extent, the resin protrusion 12A is sandwiched between the active surface 121a of the semiconductor device 121 and the mounting surface 111A of the substrate 111, and the distance between both members near the bump electrode is the resin protrusion 12A. It is held in a state separated by a thickness. In this case, since the area where the resin protrusion 12A is disposed is smaller than the area where the gap control layer 15 is disposed, the function of holding the gap (gap control function) is weak compared to the gap control layer 15, but the resin protrusion 12A. If the material is devised, a sufficient gap control function may be obtained even with the resin protrusion 12A alone.

  When the heating is further continued in the state of FIG. 5B, the sealing resin 122 is crosslinked and thermoset, and the bump electrode 10 is in conductive contact with the terminal 111dx by the sealing resin 122 even when the applied pressure is released. It is held in an elastically deformed state. At this time, as shown in FIG. 5C, since the surface of the gap control layer 15 is provided with fine irregularities 15a, the irregularity 15a increases the contact area between the gap control layer 15 and the substrate 111, The semiconductor device 121 and the substrate 111 can be more firmly fixed.

[Method for Manufacturing Semiconductor Device]
Next, the process for forming the bump electrode 10 will be described in particular for the method for manufacturing a semiconductor device of the present invention.
6 and 7 are process diagrams showing an example of a method for manufacturing the semiconductor device 121. This manufacturing process includes a process of forming the passivation film 26 (FIG. 6A), a process of forming the resin protrusion 12 and the gap control layer 15 (FIG. 6B), and a process of forming the conductive film 20 (FIG. 6C) and a step of reducing the thickness of the gap control layer 15 (FIG. 7A). FIG. 7B is a cross-sectional view of the process of FIG.

First, as shown in FIG. 6A, the passivation film 26 is formed on the active surface 121a of the substrate P on which the semiconductor element is formed. That is, after forming a passivation film 26 such as SiO ₂ or SiN on the substrate P by a film forming method, an opening 26a is formed by patterning using a photolithography method. The opening 26a is formed by forming a resist layer on the passivation film 26 by a spin coating method, a dipping method, a spray coating method, or the like, and further exposing and developing the resist layer using a mask on which a predetermined pattern is formed. Then, a resist pattern (not shown) having a predetermined shape is formed. Thereafter, the film is etched using the resist pattern as a mask to form an opening 26a exposing the electrode pad 24, and the resist pattern is removed using a stripping solution or the like. Here, dry etching is preferably used for etching, and reactive ion etching (RIE) is preferably used as dry etching. Wet etching can also be used as the etching.

  Next, on the active surface 121a of the substrate P on which the electrode pad 24 and the passivation film 26 are formed, a resin constituting the resin protrusion 12 and the gap control layer 15, for example, an acrylic resin serving as a positive resist, is 10 to 20 μm, for example. The resin film is formed by applying to a degree and further pre-baking. Then, a mask is disposed on the resin film, and the resin film is exposed to ultraviolet rays through the mask.

  Here, the mask is made of a glass plate on which a light-shielding film such as Cr is formed, for example, and has a mask having openings corresponding to the planar shapes of the resin protrusion 12 and the gap control layer 15 to be formed. Further, at the time of exposure, by adjusting the exposure conditions, the pattern of the resin protrusions 12 obtained after development is changed to a pattern whose upper surface is a convex curved surface. Specifically, so-called underexposure is performed in which the exposure and exposure are sufficiently smaller than the standard exposure amount with respect to the material and thickness of the resin film. The actual exposure (underexposure) is performed, for example, at about half of the standard exposure amount.

  When exposure is performed in this manner, the amount of exposure gradually decreases from the center of the opening toward the peripheral portion in the resin film exposed from the opening of the mask. Therefore, when the development process is performed after the exposure process is performed in this manner, even in the resin film exposed from the opening, the unexposed part generated by the decrease in the exposure amount is developed and removed. That is, since the degree of exposure on the surface layer side of the resin film gradually decreases from the center of the mask opening to the peripheral part, the resin that has become unexposed portions by developing this degree of exposure decreases. As a result, the resin film becomes a projection having a pattern whose upper surface is a convex curved surface.

  Thus, the resin protrusion 12 and the gap control layer 15 shown in FIG. 6B are formed on the active surface 121a of the semiconductor device 121. The resin protrusions 12 are formed on the four edges of the active surface 121a along the arrangement of the electrodes 24, and the gap control layer 15 is wide so as to cover the entire central portion of the active surface 121a. It is formed by area. At this stage, the gap control layer 15 and the resin protrusion 12 have the same thickness (height).

  Next, as shown in FIG. 6C, a conductive film 20 is formed as a metal wiring connecting the electrode pad 24 and the top of the resin protrusion 12 from the surface of the electrode pad 24 to the surface of the resin protrusion 12, and resin The bump electrode 10 is completed. The conductive film 20 preferably has a two-layer structure of TiW (titanium tungsten) and Au (gold).

  Specifically, a first conductive film made of TiW is first formed on the entire surface of the substrate P by sputtering or the like, and then a second conductive film made of Au is further formed on the entire surface by sputtering or the like. In forming the first conductive film, it is desirable to perform plasma treatment on the surface of the resin protrusion 12 in advance to form fine irregularities on the surface in order to increase the adhesion with the resin protrusion 12.

  Next, a resist layer is formed on the second conductive film by a spin coating method, a dipping method, a spray coating method, etc., and further, a resist layer is subjected to exposure processing and development processing using a mask on which a predetermined pattern is formed, A resist pattern having a predetermined shape (a pattern in which a region other than the predetermined conductive film pattern is opened) is formed. Thereafter, the first conductive film and the second conductive film are etched using the resist pattern as a mask, and the resist pattern is removed using a stripping solution or the like, whereby the conductive film 20 having a predetermined shape is formed.

  When the bump electrode 10 is completed as described above, as shown in FIG. 7, the entire substrate P is subjected to plasma treatment, and the thicknesses of the gap control layer 15 and the resin protrusion 12A are maintained between the active surface 121a and the counterpart substrate 111. Reduce to the same thickness as the gap (gap) to be made. The thicknesses of the gap control layer 15 and the resin protrusion 12A are set to appropriate thicknesses as long as the deformation of the bump electrode 10 is allowed. Specifically, an appropriate range based on (1) a range in which the resin protrusion 12B can be deformed, (2) a range in which the conductive film 20 can follow the deformation of the resin protrusion 12B without peeling or breaking, and the like. Set to In this embodiment, when the thickness of the bump electrode 10 is 15 μm, the thickness of the gap control layer 15 is set to about 10 μm.

When the surfaces of the gap control layer 15 and the resin protrusions 12A are scraped by such plasma treatment, the surfaces of the gap control layer 15 and the resin protrusions 12A are roughened, and a large number of fine irregularities are formed on the surfaces. This unevenness contributes to increasing the adhesive force (adhesion force) by widening the contact area with the counterpart substrate 111.
Thus, the semiconductor device 121 is completed.

  As described above, in the liquid crystal display device 100 of the present embodiment, the members (gap control layer 15 and resin protrusion 12A) having a gap control function are provided between the semiconductor device 121 and the substrate 111. Can be uniformly maintained at the thickness of the member. Therefore, in the liquid crystal display device 100 including such a semiconductor device 121, the bump electrode 10 is uniformly crushed across the entire active surface, and there is no uniform electrical variation between the bump electrodes such as contact resistance. Characteristics can be obtained.

  In addition, since fine unevenness is formed on the surface of the gap control layer 15 and the surface of the resin protrusion 12A, the unevenness increases the bonding area with the substrate 111. As a result, the semiconductor device 121 and the substrate 111 are strengthened. It is possible to adhere. Since the unevenness is formed at the same time when the thickness of the gap control layer 15 is reduced by the plasma treatment, it is not necessary to pair a new process, so that the manufacturing process is simplified and the cost is reduced. Become.

  In this embodiment, the gap control layer 15 is disposed on the active surface of the semiconductor device 121. However, the gap control layer 15 is disposed on either the active surface 121a of the semiconductor device 121 or the mounting surface 111A of the substrate 111. May be. Further, a member having such a function as the gap control layer may be disposed in the sealing resin 122 that bonds them. In this case, such a member or an adhesive layer mixed with the member is the gap control layer of the present invention. As such a member, a spacer for gap control generally used in a liquid crystal display device or the like can be used.

  In this embodiment, the gap between the semiconductor device 121 and the substrate 111 is held by the gap control layer 15 and the resin protrusion 12A. However, the gap between the two may be held only by the gap control layer 15 or the resin protrusion 12A. Is possible.

  In the present embodiment, the gap control layer 15 is provided only inside the bump electrode 10, but the position of the gap control layer 15 is not necessarily limited thereto. For example, the gap control layer 15 can be provided on both the inside and the outside of the bump electrode 10. The gap control layer 15 is desirably provided in almost all regions of the active surface 121a except for the region where the bump electrode 10 is disposed, thereby enabling more accurate gap control. However, the gap control layer 15 does not necessarily have to be formed on the entire active surface, and it is possible to provide a region where the gap control layer 15 is not partially formed in a range that does not hinder the gap control. is there.

[Modification]
8A to 8E are schematic plan views illustrating other configuration examples of the semiconductor device 121. FIG. The basic configuration of these semiconductor devices is the same as that shown in the above embodiment. That is, bump electrodes (resin protrusions 12) are provided along the outer periphery of the active surface 121a, and the gap control layer 15 is provided in almost all regions of the active surface 121a except for the region where the bump electrodes are disposed. . Therefore, the same code | symbol is attached | subjected to the same component as the said embodiment, and detailed description is abbreviate | omitted.

  In the example of FIG. 8A, a plurality of grooves 15 </ b> D extending in the illustrated vertical direction (the short side direction of the semiconductor device 121) are provided on the surface of the gap control layer 15. The groove 15D is formed at the same time on the surface of the gap control layer 15 when the resin film is patterned in the step of FIG.

  In this example, since the groove 15D is formed so as to extend from the central portion of the gap control layer 15 to the outer peripheral edge of the gap control layer 15, when the semiconductor device 121 and the counterpart substrate are bonded by the sealing resin. The escape route for the sealing resin can be formed, and no excess sealing resin is disposed between the gap control layer 15 and the counterpart substrate. Specifically, the sealing resin disposed in the central portion of the gap control layer 15 is exposed to the outside via the groove 15D and a groove (a portion where the thickness of the resin protrusion 12A is reduced) provided between the bump electrodes. Discharged. For this reason, the pressure distribution of the sealing resin becomes uniform in the active surface 121a, and thereby a more uniform amount of collapse of the bump electrode can be obtained. Further, since the groove 15D is formed at the same time when the resin film is patterned, a new process is not added and the process is simplified.

  In the example of FIG. 8B, a plurality of grooves 15 </ b> D extending in the illustrated left-right direction (long side direction of the semiconductor device 121) are provided on the surface of the gap control layer 15. The groove 15D is formed at the same time on the surface of the gap control layer 15 when the resin film is patterned in the step of FIG. In this example, the sealing resin disposed in the central portion of the gap control layer 15 is discharged to the outside from the side on the short side of the semiconductor device 121 where the bump electrode is not formed via the groove 15D. Therefore, even in this example, an excess sealing resin is not disposed between the gap control layer 15 and the counterpart substrate, and a uniform amount of bump electrode collapse can be obtained.

  In the example of FIG. 8C, no groove is formed in the gap control layer 15, and the bump electrodes (resin protrusions 12) are formed on all four sides of the semiconductor device 121. According to this configuration, the active surface 121a can be uniformly supported by the resin protrusions 12A (not shown) provided on all four sides.

  In the example of FIG. 8D, an X-shaped groove 15 </ b> D is provided on the surface of the gap control layer 15. In this example, the sealing resin disposed in the central portion of the gap control layer 15 is discharged to the outside from the corner portion of the semiconductor device 121 where the bump electrode is not formed via the groove 15D. Therefore, even in this example, an excess sealing resin is not disposed between the gap control layer 15 and the counterpart substrate, and a uniform amount of bump electrode collapse can be obtained.

  In the example of FIG. 8E, no groove is formed in the gap control layer 15, but instead, the lower resin protrusion 12 is divided into three parts, and an extra sealing resin is added by the divided parts. It can be discharged. Therefore, even in this example, it is possible to obtain a uniform collapse amount of the bump electrode.

[Electronics]
Next, an electronic apparatus including the above-described electro-optical device or semiconductor device will be described.
FIG. 9 is a perspective view showing an example of an electronic apparatus according to the present invention. A cellular phone 1300 shown in the figure includes the above-described electro-optical device as a small-sized display unit 1301 and includes a plurality of operation buttons 1302, a mouthpiece 1303, and a mouthpiece 1304.
The above-described electro-optical device is not limited to the above mobile phone, but an electronic book, a personal computer, a digital still camera, a liquid crystal television, a viewfinder type or a monitor direct-view type video tape recorder, a car navigation device, a pager, an electronic notebook, a calculator, It can be suitably used as an image display means for a word processor, a workstation, a videophone, a POS terminal, a device equipped with a touch panel, etc., and in any case, an electronic device having excellent electrical connection reliability can be provided. it can.

  The preferred embodiments of the present invention have been described above with reference to the accompanying drawings, but it goes without saying that the present invention is not limited to such examples. Various shapes, combinations, and the like of the constituent members shown in the above-described examples are examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.

It is a schematic diagram which shows the liquid crystal display device with which the semiconductor device was mounted. It is explanatory drawing of the mounting structure of a semiconductor device. It is a perspective view of a semiconductor device. It is a figure which expands and shows the terminal part of the semiconductor device. FIG. 10 is a process diagram for describing the mounting method of the same semiconductor device. FIG. 6 is a process diagram for describing the manufacturing method of the same semiconductor device. FIG. 6 is a process diagram for describing the manufacturing method of the same semiconductor device. It is a plane schematic diagram which shows the other structural example of a semiconductor device. It is a perspective view which shows an example of an electronic device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Bump electrode, 12 ... Resin protrusion, 15 ... Gap control layer, 15a ... Unevenness, 15D ... Groove, 20 ... Conductive film, 24 ... Electrode pad (electrode), 24a ... Electrode pad row | line | column, 100 ... Liquid crystal display device, 111 ... Board (circuit board), 111bx, 111cx, 111dx ... Electrode terminal, 121 ... Semiconductor device (electronic component), 121a ... Active surface, 122 ... Sealing resin (adhesive), 1300 ... Mobile phone (electronic device)

Claims (13)

An electronic component having an electrode and a bump electrode electrically connected to the electrode on an active surface, and electrically connected to a counterpart substrate via the bump electrode,
An electronic component, wherein a gap control layer is provided on the active surface to keep a constant distance between the active surface and the counterpart substrate. The bump electrode has a resin protrusion protruding from the electrode, and a conductive film disposed from the surface of the electrode to the surface of the protrusion,
The electronic component according to claim 1, wherein the electronic component is electrically connected to a counterpart substrate through the conductive film disposed on the surface of the protrusion.   The electronic component according to claim 2, wherein the gap control layer and the protrusion are made of the same material.   4. The electronic component according to claim 1, wherein the gap control layer is provided in substantially all regions of the active surface excluding a region where the bump electrodes are disposed.   The electronic component according to claim 4, wherein a groove extending from a central portion of the gap control layer to an outer peripheral edge of the gap control layer is provided on a surface of the gap control layer.   6. The electronic component according to claim 4, wherein unevenness is provided on a surface of the gap control layer. The active surface has an electrode, a resin protrusion protruding from the electrode, and a conductive film disposed from the surface of the electrode to the surface of the protrusion, and is disposed on the surface of the protrusion. A method of manufacturing an electronic component electrically connected to a counterpart substrate via the conductive film,
Forming a resin film having a certain thickness on the active surface;
Patterning the resin film to form the protrusion and a gap control layer having the same thickness as the protrusion;
Forming the conductive film from the surface of the electrode to the surface of the protrusion;
Reducing the thickness of the gap control layer to the same thickness as the thickness of the gap to be held between the active surface and the mating substrate. .   8. The method of manufacturing an electronic component according to claim 7, wherein the step of reducing the thickness of the gap control layer is performed by performing plasma treatment on a surface of the gap control layer.   9. The method of manufacturing an electronic component according to claim 7, wherein a groove is formed on the surface of the gap control layer when patterning the resin film. A circuit board having a substrate and an electronic component electrically connected to the substrate,
A circuit board comprising the electronic component according to any one of claims 1 to 6. A circuit board having a substrate and an electronic component electrically connected to the substrate,
The electronic component has an electrode on an active surface, and a bump electrode electrically connected to the electrode, and is electrically connected to the substrate via the bump electrode,
A circuit board, wherein a gap control layer is provided between the board and the active surface of the electronic component to maintain a constant distance between the board and the active surface.   The circuit board according to claim 10 or 11, wherein the substrate and the electronic component are bonded together with an adhesive. An electronic apparatus comprising the circuit board according to claim 10.

Images