IC card module

Abstract: An IC card mooule includes a substrate 12 one side of which is provided with a connection terminal 7; and a resin-sealed semiconductor IC 11 which has been previously sealed by a resin. This connection terminal and the resin sealed semiconductor IC are electrically connected to each other and are molded with a molding resin 17 in such a manner that they are covered with the molding resin so as to prevent at least the electrically-connected portion 16 between them from being allowed to appear. Accordingly, reliable modules can be efficiently manufactured, and such reliable modules can be readily mounted on IC card substrates.

Description: BACKGROUND OF THE INVENTION FIELD OF THE INVENTION The present invention relates to an IC card module, and, more particularly, to an IC module (abbreviated to "module" hereinafter) designed to be mounted on thin semiconductor devices such as IC cards. DESCRIPTION OF THE RELATED ART Fig. 1 is a side elevational cross-sectional view which illustrates a conventional module to be mounted on a thin semiconductor device such as an IC card, wherein module la includes: a circuit substrate 2 on which a circuit 1 is formed; an IC chip 4 secured to the surface of this circuit substrate 2 by means of a die bonding material 3; and sealing resin 5 for sealing both the IC chip 4 and the portion around this IC chip 4. Furthermore, the conventional IC card module 1a is structured in such a manner that a connecting terminal 7 is provided on the reverse side of a substrate core 6 of the circuit substrate 2, this connecting terminal 7 being electrically connected to the circuit 1 disposed on the obverse side of the substrate core 6 via a conductor 8 enclosed in a through hole 8a. The IC chip 4 and the circuit 1 disposed on the surface of the circuit substrate 2 are connected to each other by a metallic wire 9 or the like whereby a connection portion 10 is formed, and a portion in the vicinity of the IC chip 4 including this connection portion 10 is sealed by a sealing resin 5 such as epoxy resin. The circuit substrate 2 of the IC card module la cannot be subjected to relatively high temperatures since the same comprises, for example, a glass epoxy printed circuit substrate. Thus, the types of material that can be used as the die bonding material 3 for die-bonding the IC chip 4 are limited. In addition, the conditions for wire-bonding the circuit 1 on the circuit substrate 2 to the IC chip 4 by using a metallic wire or the like are also limited. Furthermore, since the IC chip 4 is not packed with a resin, the modules la before resin sealed need to be manufactured in clean rooms or the like. This leads to the fact that the yields obtainable in manufacturing the modules la are low and that the final products lack satisfactory reliability. In addition, the work of sealing IC chips 4 with resin raises a problem of poor working efficiency and dimensional stability due to the fact that the sealing with resin is performed by potting. If this resin-sealing work is performed by mold sealing, the work encounters another problem in that the dimensional accuracy obtained between the circuit substrate 2 and a mold is insufficient if a series molding of the circuit substrate is performed due to the difference in thermal expansion coefficient between the substrate 2 and the mold which is caused by the influence of the substrate core 6 of the circuit substrate 2. On the other hand, as prescribed in JIS-X6303, when the module 1a is to be embedded in or mounted on a base body (omitted from illustration) of the IC card, it is embedded in or mounted on a base body in the form of a laminated card made of a rigid polyvinyl chloride sheet. The module la therefore needs to be designed in a simple shape so as to be readily embedded in or mounted on a sheet of the type described above. Hitherto, when resin-packed ICs are directly embedded in IC cards and are connected to the terminal portions of the IC cards, a problem arises in that connection pins in the ICs can be broken or undulation can be created over the surfaces of the reverse sides of the IC cards since a plurality of card base bodies are laminated on each other before being pressurized. In order to overcome the above-described problems, additional work needs to be performed to create a recessed portion at a position of the card base body corresponding to a connection pin, or alternatively a connection pin is inserted into the card base body. As described above, when resin-packed ICs and the terminal portions of the IC cards are connected, the shape of the connection portion, in particular the shape of the portion in the vicinity of the pins of the resin-packed ICs becomes too complicated. This arises a problem that it is difficult for the resin packed IC in the form of a module to be embedded in or mounted on the IC card base body. An object of the present invention is to provide a module which is able to overcome the above-described problems of manufacture of modules and of mounting on IC card base bodies, and which can be effectively manufactured and shows an improved reliability. In order to achieve the above object, according to one aspect of the present invention, there is provided an IC card module as set out in Claim 1. Preferred features of this aspect of the invention are set out in Claims 2 to 12. According to another apsect of the invention there is provided a method of manufacturing an IC card module as set out in Claim 13. Preferred features of this aspect of the invention are set out in Claims 14 to 20. According to the present invention, a completed resin-packed IC is, after its quality has been confirmed, mounted on a module substrate, and is then further resin-molded for the purpose of shaping the contour as the completed module. Therefore, since the resin to be twice molded is prevented from being brought into contact directly with the IC chip, resin that can be used widely and can realize an improved manufacturing yield can be selected. In addition, the thus-selected resin can form various shaped IC card modules by using the same resin-packed ICs. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a side elevational cross-sectional view which illustrates a conventional IC card module; Fig. 2 is a side elevational view which illustrates an embodiment of an IC card module according to the present invention; Fig. 3 is a plan view which illustrates the module shown in Fig. 2, from which a portion is broken away; and Figs. 4 to 6 are side elevational cross-sectional views each of which illustrates the other embodiment of an IC card module according to the present invention. DESCRIPTION OF THE PREFERRED EMBODIMENTS Fig. 2 is a side elevational cross-sectional view which illustrates an embodiment of an IC card module 1A according to the present invention, and Fig. 3 is a plan view, from which a portion is broken away, illustrating the module 1A shown in Fig. 2. The module 1A according to the present invention comprises a resin-sealed semiconductor IC such as resin-packed IC 11, this resin-sealed semiconductor IC 11 being formed in such a manner that an IC chip thereof is previously sealed with a molding resin such as epoxy resin or the like. This resin packed IC 11 is, at the resin portion thereof, adhered to a predetermined position in an insulating body 13 formed on the surface of a substrate such as a terminal substrate 12 with an adhesive 3A made of epoxy resin or the like. As an aternative using the adhesive 3A, the resin-packed IC 11 may be temporarily held. The terminal substrate 12 comprises a so-called single-side substrate in which a connection terminal 7 is provided on a single side thereof. An insulating body 13 has openings 15 at its portion in which a connection pin 14 of the resin-packed IC 11 to be mounted is connected to the terminal substrate 12. The connection pin 14 of the resin-packed IC circuit 11 is electrically, mechanically, and directly connected to the reverse side of the connection terminal 7 via the openings 15 by soldering whereby a connection portion 16 is formed. Then, the terminal substrate 12 and the resin-packed IC 11 mounted on the former are set in a mold (omitted from the illustration) so that, as shown in Fig. 2, they are integrally formed with the connection pin 14 and the connection portion 16 at least covered by a molding resin 17. In this case shown in Fig. 2, the terminal substrate 12 on which the resin-packed IC 11 is mounted is held between and secured to a mold having a cavity in which the resin-packed IC 11 can be covered with the molding resin 17. Then, this molding resin 17 such as thermotropic liquid crystal polymer ("VECTRA C-130" manufactured by Poly Plastics Co., Ltd.) which is a thermoplastic resin is injected in the circumferential portion to the resin-packed IC 11 as to integrate the former components. As a result, a desired module is manufactured. Since this thermotropic liquid crystal polymer exhibits a high elastic modulus and a Low coefficient of thermal expansion, an advantage can be offered that it can be readily introduced into narrow gaps. If a molding with the molding resin 17 is performed, for example, if thermoplastic resin is injection-molded, its cycle can be completed within substantially 20 seconds, with which the manufacturing yield can be significantly improved in comparison to the conventional molding with epoxy resin in which it takes minutes to be completed. Figs. 4 to 6 are side elevational cross-sectional views each of which illustrates another embodiment of a module according to the present invention. A module 1B shown in Fig. 4 is arranged in such a manner that the resin-packed IC 11 and the insulating body 13 are completely submerged by the molding resin 17. A module IC shown in Fig. 5 is obtained by performing molding in such a manner that a dish-like terminal substrate 12A is used and the resin-packed IC 11 is fitted within the recessed portion of this terminal substrate 12A. A module 1D shown in Fig. 6 is obtained by: mounting the resin-packed IC 11 on a so-called double-side substrate 12B provided with the connection terminal 7 on the reverse side thereof and provided with the circuit 1 on the obverse side thereof; and molding them, similarly to the case shown in Fig. 2, with the molding resin 17. The connecting terminal 7 is electrically connected to the circuit 1 via a conductor 8 enclosed in a through hole 8a. The above-described IC card modules use thin resin-packed ICs 11 manufactured by a mass-production as to be given a usual shape and the quality of which has been previously confirmed. Therefore, any operation does not need to be performed in a clean room as that needed at the time of manufacturing the conventional modules in which the IC chips are used intact, causing the manufacturing yield to be improved, and manufacturing cost to be reduced. Furthermore, the reliability of the ICs can be maintained. The resin-packed IC 11 is mounted on the individual substrate, and they are integrally molded in such a manner that the electrical connection therebetween can be efficiently established and a predetermined simple shape can be realized. Therefore, when the thus-manufactured module is mounted on or embedded in the IC card base body, this module and the IC card base body can be readily coupled. As a result, reliable IC cards can be efficiently provided. Furthermore, the above-described additional works performed for the purpose of preventing the breakage of the connection pin of the IC or creation of undulation on the surface of the IC card becomes needless to be performed. Therefore, the resin-packed IC can be readily mounted on or embedded in the IC card. Although thermotropic liquid crystal polymer which is a thermoplastic resin is used as the molding resin 17 in the above-described embodiments, the other thermoplastic resin, such as polybuthyleneterephthalate, polyphenylenesulfide, polycarbonate and ABS resin can be used, and thermosetting resin can also be used, with which the similar effects obtained by the above-described embodiments can be obtained.

Claims: An article constituting an IC card module adapted to be mounted on a thin semiconductor device such as an IC card, and comprising: a module substrate (12) one side of which is provided with a connection terminal (7); a semiconductor IC (11) held on the other side of said substrate and provided with a projecting electrical connection pin (14) electrically connected to said connection terminal; and a moulding resin (17) covering at least part of the electrically-connected portion (14, 16) between said connection terminal and said semiconductor IC and integrally molding said substrate and said semiconductor IC , characterised in that the semiconductor IC is a resin-sealed IC unit (11) sealed with a first moulding resin, with said pin (14) projecting from its resin seal, and is embedded in a second moulding resin (17) which covers the electrical connection (14, 16) including said pin (14) and integrally moulds said substrate and said resin-sealed IC unit. An IC card module according to claim 1 wherein an insulating body (13) is disposed on the said other side of said substrate, said resin-sealed semiconductor IC is held on said insulating body, and said electrically-connected portion is disposed in an opening (15) formed in said insulating body. An IC card module according to claim 2 wherein said resin-sealed semiconductor IC and said insulating body are completely submerged by said molding resin. An IC card module according to claim 1 wherein said substrate comprises a disk-like terminal substrate, and said resin-sealed semiconductor IC is molded from said molding resin as to be fitted within a recessed portion formed in said terminal substrate. An IC card module according to claim 1 wherein said substrate is a double-sided substrate provided with a circuit on the obverse side thereof and provided with a connection terminal on the reverse side thereof which is electrically connected to said circuit, and said resin-sealed semiconductor IC is mounted on said obverse side of said double-side substrate. An IC card module according to claim 5 wherein the electrical connection between said circuit and said connection terminal is formed by a conductor enclosed in a through hole which is formed penetrating said substrate. An IC card module according to any preceding claim wherein said molding resin comprises thermoplastic resin. An IC card module according to claim 7 wherein said thermoplastic resin comprises at least one selected from polybutyleneterephthalate, polyphenylenesulfide, polycarbonate or ABS resin. An IC card module according to claim 7 wherein said thermoplastic resin comprises thermotropic liquid crystal polymer. An IC card module according to any of claims 1 to 6 wherein said molding resin comprises a thermosetting resin. An IC card module according to any preceding claim wherein said resin-sealed semiconductor IC comprises a thin resin-packed IC. An IC card comprising a card base body, and a module as claimed in any of claims 1 to 11 mounted on or embedded in the card base body. A method of making an IC card module, comprising: providing a substrate (12), having a connection terminal (7) on one side, providing a semiconductor IC (11), having electrical connections; attaching the IC to the other side of the substrate and electrically connecting it to the said connection terminal; and applying a molding resin (17) to cover at least part of the electrical connection (14, 16) between the connection terminal and the semiconductor IC and integrally molding the substrate and semiconductor IC is: characterised in that the semiconductor IC is resin-sealed before it is applied to the substrate (12) and has projecting connection pins (14), and the molding resin (17) is applied to the resin-sealed IC to embed it on the substrate and cover its electrical connections including said pins. A method as claimed in claim 13 in which the resin is applied to cover the whole of the electrical connection between the connection terminal and the semiconductor IC. A method as claimed in claim 13 or 14 in which the substrate is provided with an aperture through which the semiconductor IC is electrically connected to the connection terminal. A method as claimed in claim 13 or 14 in which the substrate is a double-sided substrate and the semiconductor IC is electrically connected to the connection terminal by way of an electrical circuit provided on the substrate on the same side of the IC, and a conductor extending through the substrate. A method as claimed in any of claims 13 to 16 in which the molding resin is applied so as to embed only part of the resin-sealed IC. A method as claimed in any of claims 13 to 16 in which the molding resin is applied so as to embed the whole of the resin-sealed IC. A method as claimed in any of claims 13 to 18 in which the molding resin is at least one of polybutyleneterephthalate, polyphenylenesulfide, polycarbonate or ABS resin. A method as claimed in any of claims 13 to 18 in which the resin comprises thermotropic liquid crystal polymer.

Inventors: BABA FUMIAKI, KODAI SYOJIRO, OCHI KATSUNORI, BABA, FUMIAKI, KODAI, SYOJIRO, OCHI, KATSUNORI, BABA, FUMIAKI C/O ZAIRYO KENYUSHO OF, KODAI, SYOJIRO C/O KITAITAMI SEISAKUSHO OF, OCHI, KATSUNORI C/O KITAITAMA SEISAKUSHO OF
Applicants: MITSUBISHI ELECTRIC CORP, MITSUBISHI DENKI KABUSHIKI KAISHA
Application year: 1989
Main classification: H01L21
IPC codes: H05K3, B42D15, G06K19, H01L23