JP2006019606A - Manufacturing method of electronic component, and electronic component and ic card - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of an electronic component which enables improvement of electrical reliability, thinning, reduction in cost and improvement of yield, the electronic component and an IC card. <P>SOLUTION: The manufacturing method of the electronic component 33 has a process for forming an uncured pattern 12' formed of a conductive paste in a region for forming a circuit pattern 12 in one major surface side of a mounting substrate 11, a process for mounting a semiconductor chip 21 on the mounting substrate 11 to bury the tip of a bump 21a in a connection area 12a as a part of the uncured pattern 12', and a process for forming a circuit pattern 12 by hardening the uncured pattern 12' and joining the bump 21a and the connection area 12a. An IC card 30 employs it. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an electronic component manufacturing method, an electronic component, and an IC card using the electronic component, and more particularly to an electronic component manufacturing method, an electronic component, and an electronic component for mounting a semiconductor chip face down on a mounting board by flip chip connection. Related to the IC card.

  In recent years, an IC card in which a semiconductor chip is embedded in a resin card base has been widely used. In particular, non-contact type IC cards are applied in various fields because of the convenience of exchanging information by simply placing the card on a card reader or holding it over.

  In such a non-contact type IC card, an electronic component in which a semiconductor chip is mounted face-down by flip chip connection on a mounting substrate is provided. This electronic component includes a semiconductor chip in which bumps are provided on a plurality of electrode portions, and a mounting substrate in which a circuit pattern made of copper serving as an antenna is provided on one main surface side. Then, the connection area consisting of one area of the circuit pattern and the bump of the semiconductor chip are bonded via the conductive adhesive layer, so that the semiconductor chip and the circuit pattern are electrically connected and the semiconductor chip is mounted. The structure is fixed on the substrate. As a method for manufacturing such an electronic component, there are the following three methods.

  First, as a first method, as shown in FIG. 3A, a conductive layer 12 ″ made of copper (Cu) or aluminum (Al) is formed on the mounting substrate 11. Next, as shown in FIG. 3B, the conductive layer 12 '' is patterned by etching to form a circuit pattern 12 serving as an antenna, and a part of the circuit pattern 12 is transferred to a semiconductor chip. A connection area 12a for connecting Next, as shown in FIG. 3 (c), an anisotropic conductive film containing filler 13a such as conductive particles on the mounting substrate 11 in a state of covering a region of the circuit pattern 12 including the connection area 12a. An adhesive layer 13 made of Anisotoropic Conductive Film (ACF) is applied. Thereafter, as shown in FIG. 3D, the bumps 21 a of the semiconductor chip 21 are thermocompression-bonded on the connection area 12 a via the adhesive layer 13. In this case, the anisotropic conductive film is melted by heating at 180 ° C. to 200 ° C., and the filler 13a made of conductive particles is sandwiched between the bump 21a and the connection area 12a. Thereby, the semiconductor chip 21 and the connection area 12a are electrically connected. Then, the semiconductor chip 21 is fixed on the mounting substrate 11 by curing the adhesive layer 13.

  As a second method, as shown in FIGS. 4A and 4B, the conductive layer 12 '' formed on the mounting substrate 11 is patterned by etching, as in the first method. Thus, the connection area 12a including the circuit pattern 12 serving as an antenna and a part of the circuit pattern 12 is formed. Next, as shown in FIG. 4C, the insulating substrate 14 provided with the through holes 14a is pasted on the mounting substrate 11 so that the through holes 14a are arranged on the connection area 12a. Next, as shown in FIG. 4D, the adhesive layer 13 is formed on the connection area 12a in the through hole 14a by filling the through hole 14a with a conductive paste. Thereafter, as shown in FIG. 4E, the bumps 21a of the semiconductor chip 21 are disposed on the adhesive layer 13 made of an uncured conductive paste, and the adhesive layer 13 is cured, whereby the adhesive layer 13 The connection area 12a and the bump 21a are joined via the via. Thereby, the semiconductor chip 21 and the connection area 12a are electrically connected, and the semiconductor chip 21 is bonded and fixed on the mounting substrate 11 (see, for example, Patent Document 1).

JP-A-10-209204 (FIG. 7).

  Further, as a third method, as shown in FIG. 5A, an uncured pattern 12 'made of a conductive paste is formed in a region on the surface of the mounting substrate 11 where a circuit pattern is to be formed. Thereafter, as shown in FIG. 5B, the uncured pattern 12 ′ is cured to form a connection area 12 a including the circuit pattern 12 and a part of the circuit pattern 12. Next, as shown in FIG. 5C, an adhesive layer 13 made of a conductive paste is formed again on the connection area 12a. Subsequently, as shown in FIG. 5D, the bumps 21 a of the semiconductor chip 21 are disposed on the adhesive layer 13. Thereafter, as shown in FIG. 5E, the connection paste 12a and the bumps 21a are joined via the adhesive layer 13 by curing the conductive paste. Thereby, the semiconductor chip 21 and the connection area 12a are electrically connected and the semiconductor chip 21 is fixed on the mounting substrate 11.

  Since the electronic component obtained in this way is built in the IC card as described above, there is a strong demand for reduction in thickness and cost.

  However, in the first to third manufacturing methods of the electronic component as described above, the adhesive layer 13 made of an anisotropic conductive film or conductive paste is interposed between the semiconductor chip 21 and the connection area 12a. In addition, an interface is generated between the bump 21a and the adhesive layer 13 and between the adhesive layer 13 and the connection area 12a. For this reason, cracks or the like are easily generated from this interface, and there is a problem in connection reliability between the semiconductor chip 21 and the circuit pattern 12.

  Further, since the thickness of the electronic component obtained is increased by the amount of the adhesive layer 13 interposed between the connection area 12a and the bump 21a, there is a limit to the reduction in thickness. For example, the electronic component is built in an IC card. In this case, the tolerance for the specified thickness of the IC card is reduced.

  Further, not only the cost for the adhesive layer 13 is required, but also a supply process and a curing process for the adhesive layer 13 are required, and the manufacturing process is likely to be complicated, so that it is difficult to reduce the cost. In particular, in the first and second manufacturing methods, since the conductive layer 12 '' is formed on the mounting substrate 11, and then the conductive layer 12 '' is patterned by etching, the manufacturing process is performed because the lithography process is performed. In addition to being complicated, an apparatus for performing a lithography process is required, which also makes it difficult to reduce costs.

  Furthermore, in the first manufacturing method described above, the bumps 21a of the semiconductor chip 21 are thermocompression bonded onto the connection area 12a via the adhesive layer 13 made of an anisotropic conductive film. As a result, it is easy to be damaged, and the yield of electronic components is reduced.

  From the above, it is possible to improve the connection reliability between the bumps of the semiconductor chip and the circuit pattern in the electronic component, and also to reduce the thickness of the electronic component, thereby reducing the cost and improving the yield. Therefore, there has been a demand for a method of manufacturing an electronic component, an electronic component, and an IC card using the same.

In order to solve the above-described problems, a method for manufacturing an electronic component according to the present invention includes a main surface of a substrate in the method for manufacturing an electronic component in which a semiconductor chip provided with a bump is fixed to the substrate via the bump. A step of forming an uncured pattern made of a conductive paste in a region for forming a circuit pattern on the side, and a semiconductor chip on the substrate so that the tip of the bump is embedded in a connection area that is a part of the uncured pattern And a step of forming a circuit pattern by curing an uncured pattern and bonding a bump and a connection area.

  According to such a method for manufacturing an electronic component, the bumps of the semiconductor chip and the connection area formed of a part of the circuit pattern are directly bonded. As a result, an interface is generated only between the bump and the connection area. Therefore, an adhesive layer is not interposed between the bump and the connection area as compared with the conventional method of manufacturing an electronic component. Interface between the semiconductor chip and the circuit pattern is improved, and the reliability of connection between the semiconductor chip and the circuit pattern is improved. Further, by directly bonding the bumps of the semiconductor chip and the connection area, an adhesive layer is not interposed, and thus a thin electronic component is formed.

  Furthermore, since the uncured pattern that becomes a circuit pattern by curing functions as an adhesive layer, the manufacturing process is simplified and reduced compared to the conventional electronic component manufacturing method because the adhesive layer is not formed. Cost can be reduced. In addition, since an uncured pattern made of a conductive paste is formed and cured to form a circuit pattern, the conductive layer is patterned compared to the first and second manufacturing methods of the conventional electronic component. Since this is not performed, a complicated lithography process does not have to be performed, and a device associated therewith is not necessary, so that the manufacturing process can be further simplified and the cost can be reduced.

  In addition, since the semiconductor chip is mounted on the substrate so that the tip of the bump is embedded in the connection area which is a part of the uncured pattern, the thermocompression bonding is performed as compared with the first manufacturing method of the conventional electronic component. Therefore, since it is not necessary to mount the semiconductor chip on the substrate, it is possible to prevent the semiconductor chip from being subjected to high temperature and high pressure and to suppress damage to the semiconductor chip.

  The present invention is also an electronic component obtained by the manufacturing method described above, and includes a semiconductor chip provided with a bump and a substrate provided with a circuit pattern on one main surface side, and the semiconductor is provided on the substrate via the bump. In the electronic component to which the chip is fixed, the bump and the connection area are bonded in a state where the tip of the bump is embedded in the connection area which is a part of the circuit pattern.

  Furthermore, an IC card according to the present invention is an IC card in which the above-described electronic component is sandwiched between a first substrate and a second substrate disposed opposite to the first substrate, and the electronic component includes bumps. A connection area in which a semiconductor chip is fixed on the substrate via a bump, and the tip of the bump is a part of the circuit pattern. It is characterized in that the bump and the connection area are joined in a state of being embedded in.

  According to such an electronic component and an IC card using the electronic component, since the bump and the circuit pattern are directly bonded, no adhesive layer is interposed between the bump and the circuit pattern. The number of interfaces generated between the two is reduced. Thereby, the crack etc. from an interface are suppressed and the connection reliability of a semiconductor chip and a circuit pattern is improved. In addition, the thickness of the electronic component is reduced because the adhesive layer is not provided.

  As described above, according to the method for manufacturing an electronic component, the electronic component, and the IC card of the present invention, the connection reliability between the semiconductor chip and the circuit pattern is improved, and thus an electronic component with high electrical reliability is obtained. be able to. Further, since an electronic component with a small thickness can be obtained, when the electronic component is built in an IC card with a prescribed thickness, the tolerance for the thickness of the IC card can be increased. Furthermore, since the manufacturing process is simplified and the cost can be reduced, the productivity is excellent. In addition, since the damage to the semiconductor chip is suppressed, the yield of electronic components can be improved.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Here, description will be made using an example of an electronic component incorporated in a non-contact type IC card. In addition, the same code | symbol is attached | subjected and demonstrated to the structure similar to what was demonstrated by background art.

<Electronic components, IC cards>
FIG. 1A is a sectional configuration diagram of a non-contact type IC card incorporating an electronic component according to an embodiment of the present invention, FIG. 1B is a plan view of the electronic component, and FIG. It is sectional drawing of an electronic component.

  As shown in FIG. 1A, an IC card 30 includes a card-shaped first substrate 31 made of, for example, polyethylene terephthalate (PET), and a second substrate 32 disposed opposite to the first substrate 31. The electronic component 33 is sandwiched between the two. The thickness of the IC card 30 is defined as, for example, 760 μm by the Japanese Standards Association (JIS).

  Here, on the main surface side of the first substrate 31, the mounting substrate 11 of the electronic component 33 is arranged in a fixed state via an adhesive layer (not shown). Further, a reinforcing plate 34 made of, for example, stainless steel for preventing damage to the semiconductor chip 21 is provided on the upper surface of the semiconductor chip 21 of the electronic component 33 via an adhesive layer (not shown).

  Then, an adhesive layer 35 made of a curable resin material is interposed between the first substrate 31 and the second substrate 32, and the first substrate 31 and the second substrate 32 are bonded to each other. The component 33 is sandwiched.

  Here, the electronic component 33 characteristic of the present invention is configured such that the semiconductor chip 21 is fixed on the mounting substrate 11 via the bumps 21a.

  As shown in FIG. 1B, the mounting substrate 11 is made of an insulating base material made of, for example, polyimide resin or epoxy resin having a thickness of 20 μm to 50 μm. A circuit pattern 12 serving as an antenna provided in a coil shape at a pitch of 1 mm to 2 mm is provided on one peripheral surface side of the mounting substrate 11. In addition, one region of the circuit pattern 12, for example, an end region of the circuit pattern 12 arranged in a coil shape, becomes a connection area 12a for connecting to a bump (see FIG. 1A) of the semiconductor chip 21. ing.

  The circuit pattern 12 is formed by curing a curable conductive paste made of, for example, Cu paste or silver (Ag) paste, and has a film thickness of 30 μm to 35 μm.

  Further, as shown in FIG. 1C, the semiconductor chip 21 is provided with bumps 21a made of, for example, gold (Au) on a plurality of electrode portions. As will be described in detail in a manufacturing method to be described later, the bump 21 a is arranged in a state where the tip of the bump 21 a penetrates the connection area 12 a which is one area of the circuit pattern 12 and reaches the surface of the mounting substrate 11. Therefore, it is provided with a height of 50 μm to 70 μm which is higher than the thickness of the circuit pattern 12.

  And the bump 21a and the connection area 12a are joined in the state which the front-end | tip part of the bump 21a was embedded in the connection area 12a mentioned above. Here, in particular, it is assumed that the tip of the bump 21 a is disposed in a state of penetrating the inside of the connection area 12 a and reaching the surface of the mounting substrate 11. In this state, the semiconductor chip 21 and the connection area 12a are electrically connected, and the semiconductor chip 21 is fixed on the mounting substrate 11.

<Method for manufacturing electronic parts>
Next, an example of a method for manufacturing the electronic component described above will be described with reference to the manufacturing process sectional view of FIG. 2 is a cross-sectional view taken along the line AA ′ of FIG. 1B.

  First, as shown in FIG. 2A, a thermosetting conductive paste containing Cu, for example, is printed on the surface of the mounting substrate 11 on the surface of the mounting substrate 11 by, for example, a screen printing method. 'Form. As described with reference to FIG. 1B, the circuit pattern forming region is arranged in a coil shape on the peripheral edge of the surface of the mounting substrate 11, and the end of the region arranged in the coil shape is Suppose that it is comprised so that it may become a connection area | region of a semiconductor chip. Here, a thermosetting conductive paste is used, but a curable conductive paste may be used, and an ultraviolet (UV) curable conductive paste may be used.

  At this time, as a screen used for printing, a mesh screen of 20 μm to 30 μm in which a metal wire knitted in a mesh shape is stretched inside the frame is used. Here, the uncured pattern 12 'made of a conductive paste is formed by a screen printing method, but the printing method may be transfer. The uncured pattern 12 ′ may be formed by a coating method using a dispenser or the like instead of using the printing method.

  Next, as shown in FIG. 2B, the semiconductor chip 21 in which bumps 21 a made of, for example, Au are provided on a plurality of electrode portions is mounted on the mounting substrate 11. In this case, the semiconductor chip 21 is disposed above the mounting substrate 11 with the bump 21a and the connection area 12a formed of a part of the uncured pattern 12 ′ facing each other, and the positions of the bump 21a and the connection area 12a are arranged. Align. Thereafter, the semiconductor chip 21 is mounted on the mounting substrate 11 so that the tip of the bump 21a reaches the surface of the mounting substrate 11 by embedding the tip of the bump 21a in the connection area 12a.

  Here, the semiconductor chip 21 is mounted on the mounting substrate 11 so that the tip of the bump 21a penetrates the connection area 12a which is a part of the uncured pattern 12 ′ and reaches the surface of the mounting substrate 11. However, it is only necessary that the tip of the bump 21a is arranged in a state of being embedded in the connection area 12a. However, it is preferable to dispose the tip of the bump 21a so as to reach the surface of the mounting substrate 11 because the thickness of the electronic component can be reduced. Moreover, since the arrangement position of the semiconductor chip 21 is defined by the height of the bump 21a, the semiconductor chip 21 can be arranged in parallel to the mounting substrate 11, and the variation in the thickness of the electronic component is suppressed.

  Next, as shown in FIG. 2 (c), the circuit pattern 12 is formed by curing the uncured pattern 12 ′ (see FIG. 2 (b)) by heating at 140 ° C. to 150 ° C. The circuit area 12 and a part of the connection area 12a are bonded to the bump 21a. Thus, the formation of the circuit pattern 12, the electrical connection between the semiconductor chip 21 and the connection area 12a, and the mechanical holding are performed in the same process, and the semiconductor chip 21 is fixed onto the mounting substrate 11 via the bumps 21a. .

  Thereafter, an underfill material is supplied between the mounting substrate 11 and the semiconductor chip 21, and the underfill material is cured to bond the mounting substrate 11 and the semiconductor chip 21, thereby mounting the mounting substrate 11 and the semiconductor chip 21. Reinforce the fixing.

  According to the manufacturing method of the electronic component 33, the electronic component 33, and the IC card 30 using the electronic component 33, the bump 21a of the semiconductor chip 21 and the connection area 12a which is a part of the circuit pattern 12 are directly bonded. Accordingly, since the connection area 12a itself functions as an adhesive layer, an adhesive layer is not formed between the bump 21a and the connection area 12a as compared with the conventional method for manufacturing an electronic component. 12 is reduced. Therefore, since cracks from the interface are suppressed, the connection reliability between the semiconductor chip 21 and the circuit pattern 12 is improved. Therefore, the electrical reliability of the electronic component 33 and the IC card 30 can be improved.

  Further, by directly bonding the bump 21a of the semiconductor chip 21 and the connection area 12a, an electronic component 33 having a small thickness can be formed because no adhesive layer is interposed. In the present embodiment, since the semiconductor chip 21 is mounted on the mounting substrate 11 so that the tip end portion of the bump 21a penetrates the connection area 12a and reaches the surface of the mounting substrate 11 in particular, a thinner electronic The part 33 can be formed. As a result, the electronic component 33 can be thinned, and when the electronic component 33 is built in the IC card 30 having a prescribed thickness, the tolerance for the thickness can be increased.

  Furthermore, in this embodiment, since the semiconductor chip 21 is mounted on the mounting substrate 11 so that the tip of the bump 21a penetrates the connection area 12a and reaches the surface of the mounting substrate 11, the connection area 12a is configured. Without being affected by the thickness of the conductive paste, the semiconductor chip 21 can be arranged in parallel at a position defined by the height of the bump 21 a with respect to the mounting substrate 11. Therefore, variation in the thickness of the electronic component 33 can be suppressed.

  In addition, since the uncured pattern 12 ′ that becomes the circuit pattern 12 by curing functions as an adhesive layer, the manufacturing process is simplified by the amount of not forming the adhesive layer compared to the conventional method of manufacturing an electronic component. And cost reduction. Furthermore, since the uncured pattern 12 'made of a conductive paste is formed and cured to form the circuit pattern 12, it is compared with the first and second manufacturing methods of the conventional electronic component described in the background art. In addition, since the conductive layer is not patterned, a complicated lithography process is not required, and no apparatus is required, which makes it possible to further simplify the manufacturing process and reduce costs, and is excellent in productivity. ing.

  In addition, since the semiconductor chip 21 is mounted on the mounting substrate 11 so that the tip of the bump 21a is embedded in the connection area 12a that is a part of the uncured pattern 12 ′, the conventional electronic component described in the background art Compared with the first manufacturing method, the semiconductor chip 21 does not have to be mounted on the mounting substrate 11 by thermocompression, and the semiconductor chip 21 is prevented from being subjected to high temperature and high pressure, and damage to the semiconductor chip 21 is prevented. It is suppressed. Therefore, the yield of the electronic components 33 can be improved.

  The present invention is particularly effective for an electronic component built in a non-contact type IC card that is strongly required to be thin and cost-cut as described in the present embodiment. In addition, not only the IC card but also electronic components built in labels and tags attached to products etc. are particularly effective.

  In the present embodiment, the example of the mounting substrate 11 made of insulating equipment has been described. However, the present invention is applicable even when the mounting substrate 11 is a wiring substrate provided with multilayer wiring.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional configuration diagram (a), a plan view (b), and a cross-sectional view (c) for explaining an embodiment of an IC card using the electronic component of the present invention. It is manufacturing process sectional drawing for demonstrating embodiment which concerns on the manufacturing method of the electronic component of this invention. It is manufacturing process sectional drawing for demonstrating the manufacturing method of the conventional electronic component (the 1). It is manufacturing process sectional drawing for demonstrating the manufacturing method of the conventional electronic component (the 2). It is manufacturing process sectional drawing for demonstrating the manufacturing method of the conventional electronic component (the 3).

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... Mounting board, 12 ... Circuit pattern, 12 '... Uncured pattern, 12a ... Connection area, 21 ... Semiconductor chip, 21a ... Bump, 30 ... IC card, 33 ... Electronic component

Claims (9)

In a manufacturing method of an electronic component for fixing a semiconductor chip provided with a bump on the substrate via the bump,
Forming an uncured pattern made of a conductive paste in a region for forming a circuit pattern on one main surface side of the substrate;
Mounting the semiconductor chip on the substrate so as to embed a tip of the bump in a connection area that is a part of the uncured pattern;
A method of manufacturing an electronic component, comprising: curing the uncured pattern to form the circuit pattern and joining the bump and the connection area. The method for manufacturing an electronic component according to claim 1, wherein in the step of forming the uncured pattern, the uncured pattern made of the conductive paste is formed by a printing method. In the step of mounting the semiconductor chip on the substrate, the semiconductor chip is mounted on the substrate so that the tip of the bump penetrates the connection area and reaches the surface of the substrate. The manufacturing method of the electronic component of Claim 1. In an electronic component comprising a semiconductor chip provided with a bump and a substrate provided with a circuit pattern on one main surface side, the semiconductor chip being fixed on the substrate via the bump,
The electronic component, wherein the bump and the connection area are joined in a state in which a tip portion of the bump is embedded in a connection area that is a part of the circuit pattern. The electronic component according to claim 4, wherein a tip portion of the bump is disposed in a state of penetrating the connection area and reaching the surface of the substrate. The electronic component according to claim 4, wherein a height of the bump is higher than a thickness of the circuit pattern. In an IC card in which an electronic component is sandwiched between a first substrate and a second substrate disposed to face the first substrate,
The electronic component includes a semiconductor chip provided with a bump and a substrate provided with a circuit pattern on one main surface side, and the semiconductor chip is fixed on the substrate via the bump,
The IC card, wherein the bump and the connection area are joined in a state in which a tip portion of the bump is embedded in a connection area which is a part of the circuit pattern. The IC card according to claim 7, wherein a tip portion of the bump is disposed in a state of penetrating the connection area and reaching a surface of the substrate. The IC card according to claim 7, wherein a height of the bump is higher than a thickness of the circuit pattern.

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