FR2793924A1 - CHIP SUPPORT MODULE - Google Patents

Abstract

Chip support module used for the manufacture of a smart card, comprising an electrically insulating support (2) with cut-out recesses (10, 12, 14) some of which form a sealing edge (12a) serving as a barrier to the flow, which allows, without additional manufacturing steps, to limit in a defined manner the sealing mass (20) relative to the chip (6) and to the connection wires (13). One or more recesses (10) are used for anchoring with the chip card when the latter is assembled with the chip support module in a mold for injection molding.

Description

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CHIP SUPPORT MODULE

DESCRIPTION

  The present invention relates to a chip support module, such as it is integrated, for example, into smart cards. A chip support module of this type is typically formed of a flat support of an electrically insulating material, and contact surfaces which are formed on a lower face of the support and are cleared towards one face

  upper support, through recesses.

  An integrated circuit chip on the upper face of the support is electrically connected to different contact surfaces by means of small connection wires, the small connection wires usually leaving from the upper face of the chip, entering the recess and extending over the corresponding contact surface. After connection, the area occupied by the chip and by the connection wires is sealed with a

sealing compound.

  A module of this type is known from document DE 34 24 241. In principle, the recesses in the support are given dimensions making it possible to accommodate the tools used during the subsequent manufacturing steps. As small as possible recesses in chip support modules of this type have the advantage of making it possible to conserve as much of the bonding force as possible between the metal contact surfaces on the one hand and the support material on the other hand . I Figures 6A, 6B and 6C show

  examples of prior art chip support modules.

  According to FIG. 6A, the underside of a flat support 100, which is cut from a strip, is provided with a metallization which is distributed by etching channels 110 in several contact surfaces 101. Recesses 105 in the support 100 leave partial areas of the contact surfaces 101 in the direction of the upper face of the support 100 so that connection wires 104 can be put in place at these locations to establish a connection between the contact surfaces 101 and connection points correspondents located on top of a chip 103 which is housed in a recess

  by inserting an insulating layer 102.

  After the execution of the connection works, the area of the chip and connection is sealed with a mass of

sealing 106.

  FIG. 6B shows that the recesses 105 have dimensions such that the chip 103 is housed in the central recess and the other recesses 105 for the outer ends of the connection wires 104 have dimensions allowing execution of the connection works

with an appropriate tool.

  While in FIG. 6A, the sealing mass extends so that the recesses 105 forming the connection points are completely filled and lie inside the outer peripheral edge of the sealing mass, the outer edge of the sealing mass 106 ′ is, according to FIG. 6C, inside a recess 105. This situation

  corresponds to the document DE 34 24 241 mentioned above.

  As, in FIG. 6B, the recesses 105 made for the ends of the connection wires are very small, the extension of the sealing mass in the region of these small recesses can practically not be controlled. Depending on the nature of the sealing mass and its quantity, the sealing mass only partially penetrates into the recess 105 or flows beyond it, as shown in

Figure 6A.

  To control the lateral flow of the sealing mass, it is proposed in document EP 0 391 790 Ai to have on the upper face of the support, an embankment which surrounds the area of the chip and

  limits the lateral flow of the sealing compound.

  Such a solution is obviously accompanied by considerable work. As another measure aimed at limiting in a definite way the sealing mass, the document DE 43 26 816 Ai proposes to mill with steps the

edge area of a recess.

  The object of the invention is to indicate a chip support module in which the contour of the sealing mass can be defined with means

relatively simple.

  According to the invention, this objective is achieved by chip support modules characterized by the fact that at least one or some of the recesses are produced in the form of large-area sealing mass housings whose external limitation forms a barrier to flow, support bands located between recesses of this type

  mechanically connecting neighboring contact surfaces.

  According to an advantageous embodiment of the invention, the width of the strips is less than the width of the sealing mass housings, the chip housing is located in a recess, at least two contact surfaces respectively comprising a connection point of connection wire are released in the recess forming the chip housing and these contact surfaces, at least two in number, are electrically connected with a wire connection recess for an external conductive wire, the external limitation of the recess forming the chip housing forming a flow barrier, at least one additional recess is provided as an anchoring recess, and the chip housing is surrounded by an etching channel whose external limitation forms a flow barrier . The invention also relates to a chip card with a chip support module inserted by injection molding and to a method of manufacturing a chip card with a chip support module, characterized in that one sets up the chip support module in an injection molding mold and that by injection of injection molding material into the anchoring recess, a connection is made by complementarity of shapes between the card body and the

chip support module.

  The invention creates a chip support module with a flat support on the underside of which are made contact surfaces which are released towards the upper face of the support by means of recesses in the support in order to create

  connection possibility for connection wires.

  The chip itself is preferably also housed in

  an appropriately sized recess.

  Unlike the prior art, the recesses do not have dimensions as small as possible but at least some of the recesses, used to receive the sealing mass, have dimensions as large as possible, in any case significantly larger than the dimensions required for the use of tools for connection of connection wires. These recesses extend widely over the entire width of the contact surfaces so that adjacent recesses are not

  connected only by a narrow band of the support.

  When the fluid sealing mass is applied to the connected module, the material flows from the point of application, that is to say usually from the housing of the chip, to the outside. The large recesses used to receive the sealant can absorb a considerable amount of sealant. In the external zone, that is to say in the zone of the module situated radially on the outside with respect to the chip housing, the sealing mass can, as it flows, reach the edge of the recesses and there accumulate. The sealing mass, which flows radially outwards from the middle of the chip housing and accumulates on the outer limitation of the sealing mass housings, rises upwards on the limitation approximately to the upper edge of the band that forms the limitation. If there is enough space, the sealing mass can also be deflected laterally, i.e. substantially perpendicular to the direction of radial flow.

outward facing.

  The measures according to the invention have a series of advantages. Since relatively little support material is present in the sealed area of the module, the support material has only a slight influence on the nature of the entire encapsulation formed by the sealing mass. As the sealing compound, a material can be chosen which guarantees optimum connection between the sealing compound and the metal surface of the contact surfaces. As the mechanical resistance of the contact surfaces is mainly achieved by the sealing mass, the material of the chip card can be chosen with a view to optimal assembly with the material of the card

  chip in which the chip support module is integrated.

  By choosing an appropriate material, the support material can be welded without glue to the card material, for example by laser welding, welding by

  ultrasound, high frequency welding or the like.

  It is possible, without additional processing steps, to create a sealing edge serving

barrier to flow.

  In addition to a recess for an integrated circuit chip and recesses, serving as sealing mass housings, for the outer ends of connection wires, at least one additional recess is preferably provided in the form of a recess. anchor. This recess in the support is not used to receive a connection wire but is filled with plastic during the subsequent processing of the chip support module when the module is assembled with a card blank. To do this, the chip support module is inserted into an injection molding mold and the card body is manufactured by injecting material for injection molding. The injection molding material fills the anchoring recess so that there is an assembly by complementarity of shapes of the card blank and the chip support module. This intimate mechanical assembly is obtained without additional processing steps. The number of anchoring recesses is not subject to any

special limitation.

  The anchoring recesses can be recesses surrounded on all sides by bands. When the anchoring recesses are in an edge zone of the module, they can also be open towards the outside, that is to say that they are limited only in a partial zone by strips of the support. In the case of such an arrangement, the metal contact surfaces are exposed in the external peripheral zone of the module. The contact surfaces electrically isolated from each other are first of all held by the strips of the support only in partial zones of the etching channels extending between them, then also by the mass of

  sealing after application.

  In a particular embodiment of the invention, at least two recesses are arranged as wire connection recesses for external conductive wires. The contact surfaces which are released in said recesses extend inside the area of the chip housing and are connected to the chip there with connection wires. The external limitation of the recess forming the chip housing constitutes a

barrier to flow.

  In a particular aspect, the invention provides that the chip housing is provided on the side, turned away from the support, of a contact surface, the chip housing being surrounded by an etching channel. This etching channel can be interrupted at places where an electrical connection is desired between contact surface areas on one side and the other of the etching channel. The propagation of the sealing mass which seals the chip is stopped by the etching channel which is produced in the contact material

metallic and surrounds the chip.

  Other characteristics and advantages of the invention will emerge more clearly on reading

  the description below of examples of implementation of

  the invention, made with reference to the accompanying drawings, in which: FIGS. 1A and 1B are respectively a sectional view of a chip support module with sealing mass and a top view of a massless chip support module 2A and 2B show another embodiment of the chip support module according to the invention, FIG. 2A being a sectional view of a chip support module with chip and sealing mass and FIG. 2B representing the chip support module without chip or sealing mass, FIG. 3 is a partial top view of another embodiment of a chip support module according to the invention, FIGS. 4A , 4B and 4C are respectively a cross-sectional view, a longitudinal sectional view and a top view of a particular embodiment of a chip support module according to the invention, FIGS. 5A and 5B are respectively a longitudinal section view and a top view of a chip support module with external connection lines, the chip being arranged on a contact surface of the module, and FIGS. 6A, 6B and 6C are different views

representing the prior art.

  As shown in FIGS. 1A and 1B, an electrically non-conductive support 2 produced by cutting a raw strip of module has on its underside several contact surfaces 4 made of a metallic material, the contact surfaces 4 being separated from one another others by etching channels 18. Several recesses 10, 12, 14 are produced by cutting in the support 2, which recesses form on the outer edge of the anchoring recesses 10, in the middle of the support a recess the chip housing 14 and around the chip housing recess 14, several connection recesses 12. The upper faces released from the contact surfaces 4 in the recesses 12 serve to connect different chip connections on the upper face of the integrated circuit chip 6 to these surfaces

  contact via connection wires 13.

  The integrated circuit chip 6 is arranged on an upper face of a contact surface by means of an insulating layer 8. After the connection, a sealing mass is applied to the integrated circuit chip 6 and its peripheral zone. 20 which, due to its fluidity, flows outwards, the fluidity and the quantity of the sealing mass 20 being adjusted to the dimensions of the zone to be encapsulated so that the sealing mass 20 fills all the cavities of the recesses 12 and 14 but only flows to the outer edges 12a of the connection recesses 12. The outer edges 12a of the connection recesses 12 thus serve as a barrier to flow, the dimensions of the encapsulation zone thus being clearly defined. The quantity of the sealing mass 20 can vary within certain limits without this variation causing the sealing mass not to fill all the areas of the connection recesses 12 or to pass over the

  outer edges 12a of these recesses.

  In this embodiment, the various contact surfaces 4 are held mechanically only by narrow strips 15, 16, 17 and 19 of the material of the support 2, as can be seen in the top view of FIG. 1B. The recess 14 is surrounded by bands 15 forming a rectangle and the recesses 12 are surrounded by the bands 15, by it sections of bands 19 extending radially and by central bands 17 extending substantially in the peripheral direction. The width ratios of the bands and of the recesses are indicated on the left-hand side of FIG. 1B: the width d2 of the radial bands 19 is clearly less than the width dl of the recesses 12 and of the anchoring recesses 10. The latter are surrounded by outer strips 16 extending in the peripheral direction of the module and by sections of the strips 19 and 17. The dimensions of the strips 16 and 17 and of the recesses 10, 12 in the radial direction (length) are similar and

  therefore correspond approximately to the ratio d2: dl.

  As is apparent from the description below

  above, special measures are not necessary to limit the flow of the sealing mass 20 when the recesses 12 have a sufficiently large area. When the flowing sealant meets the edges 12a, it is stopped at the edges so that it cannot overflow into the area

of tape.

  Figures 2A and 2B show a second embodiment of the invention. Only the differences compared to the mode of implementation according to

  FIGS. 1A and 1B will be explained here.

  While in the embodiment according to FIGS. 1A and 1B, the strips 15, 16 and 17 extending in the peripheral direction form, together with the strips extending substantially radially, the connection recesses 12 and the recesses anchor 10, the outer zones of the radial strips 19 and the outer strips 16 extending in the peripheral direction are eliminated in the embodiment according to FIGS. 2A and 2B. The outer zones of the contact surfaces 4 thus form cantilevered parts which, in the region of the chip housing recess 14, are held only by the bands 15 which are there and by radial bands. After the application of the sealing mass (FIG. 2A), the contact layers find an additional mechanical support due to the good adhesion between the material of the contact surfaces 4 and the sealing mass 20. The outer ends in door to false contact surfaces 4 are sealed and fixed by the plastic during the injection of the

module in a draft map.

  FIG. 3 shows a third mode of implementation of the invention which differs from the mode of implementation according to FIGS. 1A and 1B by the fact that

  the anchoring recesses 10 are entirely eliminated.

  The narrow strips 17 of FIG. 1 have become large-area support zones 17a which extend to the outside edge of the module. The construction is

for the rest identical.

  It should be noted at this point that due to the large surface recess 12 of the contact surfaces and the small part that the support material 2 represents in the total surface of the module in the sealing zone, the mass can be chosen. sealing so that it adheres as well as possible to the contact surfaces. However, the support material can be chosen so that the assembly of the module with the card blank not shown here during the manufacture of the smart card is as simple as possible. If an appropriate material is chosen, the support can, in zone 17a, be welded with the card material and the use can be eliminated.

glue.

  FIGS. 4A, 4B and 4C represent another embodiment of the invention for use in contactless smart cards, embodiment in which a large continuous recess 14 is provided for housing the chip of integrated circuit 6 as well as connection wires. There are two contact surfaces 4 which are electrically separated from each other by a single etching channel 18, continuous and in the form of meanders. In the support 2, a recess 22 is located above each of the two contact surfaces 4, which recess clears a relatively large area from the contact surface 4 considered in order to offer the possibility of connecting an external conductor 24 which forms a coil for contactless energy and data transmission. Two ends of the coil 24, each connected in a recess 22, are shown in the figure. Other conductors extend over the module shown in FIGS. 4B and 4C

  without, however, being electrically connected to it.

  In the region of the chip 6, the latter is electrically connected in two places with one and the other of the contact surfaces 4, by means of connection wires 13. In this embodiment, the mass sealing 20 is also held in the recess 14, as seen particularly clearly in Figures 4C and 4A. The sealing mass 20 surrounds the integrated circuit chip 6 on the one hand and the outer ends of the connection wires

13 on the other hand.

  As can be clearly seen in FIG. 4A, the two contact surfaces 4 separated from each other by the etching channel 18 are connected together by

through a band 16.

  FIGS. 5A and 5B represent an embodiment in accordance with a particular aspect of the invention. A support 32 has metallic contact surfaces 34 which are electrically separated by an etching channel 36. The integrated circuit chip 6 is electrically connected with the two contact surfaces 34 by connection wires 13. The two contact surfaces 34 are connected to the coil 24 by

connection areas.

  To limit the propagation of the sealing mass 20, the integrated circuit chip 6 is surrounded by an etching channel 38. The etching channel is only interrupted at narrow places 40 to establish the electrical connection of the chip 6 with the external lines 24 via the connection wires 13 and the contact surfaces. The etching channel 38 is produced at the same time as the etching channel 36 separating the two contact surfaces

  4, that is to say without additional operating step.

Claims (8)

  1. Chip support module with a flat non-conductive support (2) on the underside of which are made contact surfaces (4) which are released towards the upper face of said support by means of recesses (10, 12, 14), an integrated circuit chip (6) disposed in a housing being electrically connected to at least one contact surface (4) released via connection wires (13) and the chip as well as the connection wires being embedded in a sealing mass (20), characterized in that at least one or some of the recesses (12, 14) are produced in the form of large-mass sealing mass housings whose external limitation forms a barrier when flowing, bands (15, 16, 17, 19) of the support (2) located between recesses of this type mechanically connecting surfaces contact (4) neighbors.   2. Chip support module according to claim 1, characterized in that the width of the strips (15, 16, 17, 19) is less than the width of the sealing mass housings.   3. Chip support module according to claim 1 or 2, characterized in that the housing   chip is located in a recess (14).   4. chip holder module according to claim 3, characterized in that at least two contact surfaces (4) respectively comprising a connection wire connection point are released in the recess (14) forming the chip housing and that these contact surfaces (4), at least two in number, are electrically connected with a wire connection recess (22) for an external conductive wire (24), the external limitation of the recess forming   the chip housing forming a flow barrier.   5. Chip support module according to claim 3 or 4, characterized in that at least one additional recess (10) is provided as an anchoring recess. 6. Smart card with a support module   chip according to one of claims 1 to 5 inserted by injection molding.   7. A method of manufacturing a chip card with a chip support module according to claim 5, characterized in that the chip support module is placed in an injection molding mold and that by injection of material injection molding in the anchoring recess (10), a connection is made by complementarity of shapes between the card body and the chip support module.   8. Chip support module with an electrically non-conductive flat support (32) and an etched metallization layer to form contact surfaces (34) on which a chip housing is located, and with a sealing mass (20) enclosing the integrated circuit card (6) located in the chip housing, characterized in that the chip housing is surrounded by an etching channel (38) whose external limitation   forms a barrier to flow.