U.S. patent application number 09/331176 was filed with the patent office on 2002-06-13 for circuit chip mounted card and circuit chip module.
Invention is credited to CHIMURA, SHIGEMI, IKEFUJI, YOSHIHIRO, OKADA, HIROHARU.
Application Number | 20020070280 09/331176 |
Document ID | / |
Family ID | 18416884 |
Filed Date | 2002-06-13 |
United States Patent
Application |
20020070280 |
Kind Code |
A1 |
IKEFUJI, YOSHIHIRO ; et
al. |
June 13, 2002 |
CIRCUIT CHIP MOUNTED CARD AND CIRCUIT CHIP MODULE
Abstract
Oppositely arranged bumps (82,84) are electrically connected by
connecting two IC chips (76,78) through an anisotropic conductor
(80) to form an IC chip module (74). With IC chip module (74)
having such structure, two IC chips (76,78) provided with functions
of a processing portion and an antenna are simply stacked to
provide a function for communication, and arrangement of
interconnection outside IC chip (76,78) is not necessary. Thus,
accidental breakage of the interconnection is avoided and assembly
is extremely facilitated. Therefore, a circuit chip mounted card
with higher reliability and reduced manufacturing cost and the like
can be provided.
Inventors: |
IKEFUJI, YOSHIHIRO; (KYOTO,
JP) ; CHIMURA, SHIGEMI; (KYOTO, JP) ; OKADA,
HIROHARU; (KYOTO, JP) |
Correspondence
Address: |
ARENT FOX KINTNER PLOTKIN & KAHN
1050 CONNECTICUT AVENUE, N.W.
SUITE 400
WASHINGTON
DC
20036
US
|
Family ID: |
18416884 |
Appl. No.: |
09/331176 |
Filed: |
June 22, 1999 |
PCT Filed: |
December 22, 1997 |
PCT NO: |
PCT/JP97/04772 |
Current U.S.
Class: |
235/492 |
Current CPC
Class: |
H01L 2924/0002 20130101;
G06K 19/0726 20130101; G06K 19/07749 20130101; G06K 19/072
20130101; G06K 19/0723 20130101; H01L 2924/0002 20130101; G06K
19/07745 20130101; H01L 2924/00 20130101 |
Class at
Publication: |
235/492 |
International
Class: |
G06K 019/06 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 27, 1996 |
JP |
8-351377 |
Claims
1. A circuit chip mounted card provided with an antenna for
communication utilizing an electromagnetic wave and a processing
portion performing a process for communication, comprising: a first
circuit chip including at least a portion of the processing portion
and having a terminal; and a second circuit chip including the
antenna and a remaining portion of the processing portion and
having a terminal, and characterized in that said terminals are
electrically connected by stacking said first circuit chip and said
second circuit chip in a direction of thickness of the card.
2. The circuit chip mounted card according to claim 1,
characterized in that a terminal is provided for said first circuit
chip on a side of said second circuit chip and a terminal is
provided for said second circuit chip on a side of said first
circuit chip oppositely to said terminal provided for said first
circuit chip, and said first circuit chip and said second circuit
chip are directly stacked and connected.
3. The circuit chip mounted card according to claim 1,
characterized in that a terminal is provided for said first circuit
chip on a side of said second circuit chip and a terminal is
provided for said second circuit chip on a side of said first
circuit chip oppositely to said terminal for said first circuit
chip, and said first circuit chip and said second circuit chip are
stacked and connected through an anisotropic conductor.
4. The circuit chip mounted card according to claim 1,
characterized in that said second circuit chip is provided with a
capacitor and a coil forming said antenna.
5. The circuit chip mounted card according to claim 4,
characterized in that a resonance circuit is formed by at least one
capacitor and coil of circuit elements forming said second circuit
chip.
6. The circuit chip mounted card according to claim 4,
characterized in that said coil is formed of a metal
interconnection layer in a loop like shape.
7. The circuit chip mounted card according to any of claims 4 to 6,
characterized in that at least one of said capacitors is formed of
a ferroelectric substance.
8. The circuit chip mounted card according to any of claims 1 to 3,
characterized in that said first circuit chip is provided with a
non-volatile memory and a modulating/demodulating circuit forming
the processing portion.
9. A circuit chip mounted card provided with an antenna for
communication utilizing an electromagnetic wave and a processing
portion performing a process for communication, comprising: a first
base material; a second base material arranged with a prescribed
distance from the first base material in a direction of thickness
of the card; a core member layer arranged between the first base
and the second base; and a circuit chip module arranged in said
core member layer, and characterized in that said circuit chip
module is a composition of a first circuit chip including at least
a portion of the processing portion and having a terminal and a
second circuit chip including an antenna and a remaining portion of
the processing portion and having a terminal provided oppositely to
said terminal stacked in the direction of thickness of the card
through an anisotropic conductor to electrically connect said
terminals
10. The circuit chip mounted card according to any of claims 1 to
9, characterized in that a reinforcing member including a frame
arranged to surround said first circuit chip and said second
circuit chip in a direction of a face orthogonal to the direction
of thickness of the card is provided in the card.
11. A circuit chip module forming a card with a circuit including
an antenna for communication utilizing an electromagnetic wave and
a processing portion performing a process for communication,
comprising: a first circuit chip including at least a portion of
the processing portion and having a terminal; and a second circuit
chip including the antenna and a remaining portion of the
processing portion and having a terminal, and characterized in that
said first circuit chip and said second circuit chip are stacked in
a direction of thickness of the card to electrically connect said
terminals.
12. Circuit chip module according to claim 11, characterized in
that the electrical connection of said terminals is obtained by an
anisotropic conductor interposed between said first circuit chip
and said second circuit chip.
13. The circuit chip module according to claim 11, characterized in
that a resonance frequency of a resonance circuit including a
capacitor and a coil of the antenna provided in said first and
second circuit chips can be adjusted.
14. The circuit chip module according to claim 11, characterized in
that a desired resonance frequency is obtained by selectively
disconnecting an interconnection for a plurality of capacitors
preliminary provided in said first and second circuit chips.
15. The circuit chip module according to claim 13, characterized in
that a desired resonance frequency is obtained by selectively
disconnecting an interconnection for a plurality of coils
preliminary provided in said first and second circuit chips.
16. A composition of circuit chips including a first circuit chip
and a second circuit chip in a stack, characterized in that a
terminal is provided for said first circuit chip on a side of said
second circuit chip, a terminal is provided for said second circuit
chip on a side of said first circuit chip, and said first circuit
chip and said second circuit chip are stacked to electrically
connect said terminal provided for said first circuit chip and said
terminal provided for said second circuit chip, and at least one of
said first circuit chip and said second circuit chip is provided
with a detour interconnection for electrically connecting two
terminals of said one circuit chip, so that two terminals of the
other circuit chip respectively connected to said two terminals are
electrically connected.
17. A circuit chip mounted card provided with a circuit chip module
including a composition of a first circuit chip and a second
circuit chip in a stack, wherein said circuit chip module is
characterized in that a terminal is provided for said first circuit
chip on a side of said second circuit chip, a terminal is provided
for said second circuit chip on a side of said first circuit chip,
and said first circuit chip and said second circuit chip are
stacked to electrically connect said terminal provided for said
first circuit chip and said terminal provided for said second
circuit chip, and at least one of said first circuit chip and said
second circuit chip is provided with a detour interconnection for
electrically connecting two terminals of said one circuit chip, so
that two terminals of the other circuit chip respectively connected
to said two terminals are electrically connected by said detour
interconnection.
Description
TECHNICAL FIELD
[0001] The present invention relates to circuit chip mounted cards
and circuit chip modules, and more particularly to a circuit chip
mounted card and a circuit chip module with increased reliability,
reduced manufacturing cost and the like.
BACKGROUND ART
[0002] Non-contact type IC cards are used for the gate of the ski
lift, the gate at the station, automatic sorting of parcels and the
like. A conventional non-contact type IC card is exemplified in
FIG. 12. An IC card 2 shown in FIG. 12 is an IC card of a single
coil type, and includes a coil 4, capacitors C1 and C2 and an IC
chip 8.
[0003] Capacitors C1 and C2 and IC chip 8 are included in a film
substrate formed of synthetic resin. The substrate including
capacitors C1 and C2 and IC chip 8 are referred to as a tab (tab:
tape automated bonding) 10.
[0004] FIG. 13A is a cross sectional view showing IC card 2. A core
member 12 of synthetic resin is interposed between surface layer
materials 14 and 16. Tab 10 including capacitors C1 and C2 and IC
chip 8 is fixed to surface layer material 14 which is exposed to a
cavity 18 in core member 12. A connection of tab 10 and IC chip 8
is covered with a sealing material 9 of epoxy resin or the
like.
[0005] Coil 4 is arranged between surface layer material 14 and
core member 12. A wire 20 connects coil 4 and tab 10.
[0006] FIG. 13B is a circuit diagram showing IC card 2. IC card 2
receives an electromagnetic wave transmitted from a reader/writer
(reading/writing apparatus, not shown) by a resonance circuit 22
formed of coil 4 and capacitor C1 as a power source. It is noted
that capacitor C2 is used for smoothing power.
[0007] In addition, a control portion (not shown) provided in IC
chip 8 decodes information transmitted by the electromagnetic wave
for response. The response is performed by changing an impedance of
resonance circuit 22. The reader/writer obtains a content of the
response by detecting a change in an impedance (impedance
reflection) of its own resonance circuit (not shown) due to the
change in the impedance of resonance circuit 22 on the side of IC
card 2.
[0008] Thus, the use of IC card 2 allows data communication in a
non-contact state without a power supply source in the card.
[0009] However, the above described conventional IC card suffers
from the following problem.
[0010] In IC card 2, coil 4 and tab 10 must be connected by wire
20. On the other hand, IC card 2 is often put in a wallet or a
pocket of a trouser, where it is subjected to considerable bending,
twisting and pressing forces. However, a thickness t of IC card 2
shown in FIG. 13A is standard and not so thick. Thus, it is not
provided with a significant rigidity against such bending, twisting
and pressing forces. Therefore, if IC card 2 is subjected to a
significant bending force or the like, a considerable deflection is
caused. Such deflection may result in a breakage of wire 20 or
disconnection of wire 20 and coil 4 or tab 10. In addition, wire 20
may not be well connected to coil 4 or tab 10.
[0011] Further, to ensure a space for coil 4, tab 10 must
restrictively be positioned. Thus, in some cases, tab 10 must be
provided in a position where a significant deflection is caused.
This may result in significant deformation of IC chip 8.
Accordingly, IC chip 8 is cracked and does not well function as an
IC card.
[0012] As described above, the conventional IC card is difficult to
handle and lacks in reliability.
[0013] Moreover, as coil 4 and tab 10 must be connected by wire 20,
complicated assembly is involved, thereby increasing a
manufacturing cost. In addition, provision of capacitors C1 and C2
and the like in tab 10 further increases the manufacturing
cost.
DISCLOSURE OF THE INVENTION
[0014] An object of the present invention is to provide a circuit
chip mounted card with high reliability and low manufacturing cost
by overcoming the aforementioned problem related to the
conventional card.
[0015] According to one aspect, the circuit chip mounted card of
the present invention which achieves the above object includes: an
antenna for communication utilizing an electromagnetic wave; a
processing portion performing a process for communication; a first
circuit chip including at least a portion of a processing portion
and having a terminal; and a second circuit chip including the
antenna and the remaining portion of the processing portion and
having a terminal, and is characterized in that the terminals are
electrically connected by stacking the first and second circuit
chips in a direction of thickness of the card.
[0016] According to the present invention, such structure
eliminates the need for arranging the interconnection outside the
circuit chip because a function of communication is achieved simply
by stacking two circuit chips including the functions of the
processing portion and antenna. Thus, insufficient connection
caused by external arrangement of the interconnection is avoided.
Further, even if the deflection is repeatedly caused for the card,
breakage of the external arrangement of the interconnection or
accidental disconnection would be avoided.
[0017] In addition, as the antenna is included in the second
circuit chip which is in turn stacked on the first circuit chip,
the positional restriction of the circuit chip to ensure a space
for the antenna is eliminated. Thus, the stacked circuit chips with
a small area when viewed from above is provided in an arbitrary
position where a significant deflection would not be caused. As a
result, even when a significant force is applied to the card, the
circuit chips would not significantly be deformed.
[0018] Further, as the interconnection needs not be externally
arranged, assembly is extremely facilitated. Thus, reduction in the
manufacturing cost is achieved. In addition, as the capacitor is
also included in the circuit chip, the work for mounting the
capacitor is not necessary. This results in further reduction in
the manufacturing cost. Therefore, the circuit chip mounted card
with high reliability and low manufacturing cost is achieved.
[0019] The circuit chip mounted card according to the present
invention having the above described structure is obtained
preferably by providing the terminal for the first circuit chip on
the side of the second circuit chip, providing the terminal for the
second circuit chip on the side of the second circuit chip such
that it is opposite to the terminal for the first circuit chip, and
directly connecting the first and second circuit chips in a
stack.
[0020] Such structure allows two circuit chips to be readily
connected to form a module using a conventional technique for
connecting the terminals. Thus, further reduction in the
manufacturing cost is achieved as workability during manufacture
increases.
[0021] According to another aspect, a circuit chip mounted card of
the present invention provided with an antenna for communication
utilizing an electromagnetic wave and a processing portion
performing a process for communication includes: a first base
material; a second base material arranged in a direction of
thickness of the card spaced from the first base material with a
prescribed distance; a core member layer interposed between the
first and second base materials; and a circuit chip module arranged
in the core member layer. The circuit chip mounted card is
characterized in that it is a composition of a first circuit chip
including at least a portion of the processing portion and having a
terminal and a second circuit chip including the antenna and the
remaining portion of the processing portion and having a terminal
arranged opposite to the terminal of the first circuit chip which
are stacked and connected in a direction of thickness of the card
through an anisotropic conductor to electrically connect the
terminals.
[0022] According to the present invention, such structure allows
two circuit chips to be securely connected with the anisotropic
conductor interposed.
[0023] In most cases, an opening is provided in the circuit chip
for external arrangement of the interconnection before the circuit
chip is mounted in the card, which opening leads to an
interconnection layer of aluminum or the like through a protection
film on a surface. Thus, the aluminum of the interconnection layer
may suffer from corrosion during a period from the manufacture of
the circuit chip to mounting in the card and due to secular change
after assembly. In the circuit chip mounted card according to the
present invention, the first and second circuit chips can be
connected through the anisotropic conductor after manufacture, as
external arrangement of the interconnection is not necessary when
they are mounted in the card. In other words, corrosion of the
aluminum of the interconnection layer or the like is reduced as the
first and second circuit chips are closely connected through the
anisotropic conductor.
[0024] In a preferred embodiment of the circuit chip mounted card
according to the present invention, a reinforcing member including
a frame which is arranged to surround the first and second circuit
chips in a direction of the face of the chip is provided in the
card.
[0025] Such structure effectively increases rigidity of the card in
vicinity of the circuit chip while ensuring a space for the stacked
circuit chips. Thus, even if significant bending, twisting and
pressing forces are applied to the card, the stacked circuit chips
would not significantly be deformed. In other words, the circuit
chip mounted card is provided with increased reliability.
[0026] According to one aspect, a circuit chip module of the
present invention forming a card with a circuit including an
antenna for communication utilizing an electromagnetic wave and a
processing portion performing a process for communication includes:
a first circuit chip including at least a portion of the processing
portion and a terminal; and a second circuit chip including the
antenna and the remaining portion of the processing portion and
having a terminal, and is characterized in that the first and
second circuit chips are stacked in a direction of thickness of the
card to electrically connect the terminals.
[0027] Such structure of the circuit chip module according to the
present invention enables a communication function to be performed
only by a small circuit chip module. Thus, elements in the card can
more freely be arranged. In addition, as a preliminary formed
single module is merely involved for assembly, the manufacturing
cost is further reduced with increased workability.
[0028] In a preferred embodiment of the circuit chip module
according to the present invention, a resonance frequency of a
resonance circuit including a capacitor provided inside the circuit
chip and a coil for the antenna can be adjusted.
[0029] Such structure allows the capacitance or inductance of the
resonance circuit to be adjusted after the capacitor and coil are
formed in the circuit chip. Thus, the resonance frequency can be
adjusted after formation of circuit elements though these circuit
elements of the resonance circuit are all formed in the circuit
chip.
[0030] More specifically, the circuit chip mounted card is provided
with high reliability as the resonance frequency can be maintained
at a prescribed level to some extent even if there is a variation
in manufacturing conditions. Further, since a circuit chip
corresponding to various resonance frequencies is obtained without
changing a mask pattern for forming the circuit elements in a
manufacturing process of the circuit chip, the manufacturing cost
is not increased.
[0031] According to another aspect, a circuit chip module of the
present invention is a composition of circuit chips including
stacked first and second circuit chips, and characterized in that
at least one of the first and second circuit chips is provided with
a detour interconnection which electrically connects two terminals
of the above mentioned one circuit chip and the detour
interconnection electrically connects two terminals of the other
circuit chip respectively connected to the two terminals.
[0032] With such structure, the circuit chip module according to
the present invention can only perform an essential function when
two circuit chips are connected. Thus, even when the circuit chip
module is divided into two circuit chips, it is difficult to
analyze the function by each terminal. A plurality of detour
interconnections would further make it difficult to analyze the
function. In other words, the circuit chip module with high
security is achieved.
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] FIG. 1 is a view showing an overall appearance of a
non-contact type IC card 70 according to one embodiment of the
present invention.
[0034] FIG. 2 is a cross sectional view taken along the line II-II
in FIG. 1.
[0035] FIG. 3A is a front view showing an IC chip module 74,
and
[0036] FIG. 3B is a view showing elements of IC chip module 74
before they are connected together.
[0037] FIG. 4 is a schematic diagram showing an IC chip 76 shown in
FIG. 3B when viewed from above (from the side of a bump 82).
[0038] FIG. 5 is a schematic diagram showing an IC chip 78 shown in
FIG. 3B when viewed from below (from the side of a bump F4).
[0039] FIG. 6 is a diagram shown in conjunction with a detour
interconnection and dummy bump.
[0040] FIG. 7 is a cross sectional view showing a non-contact type
IC card 30 according to another embodiment of the present
invention.
[0041] FIG. 8 is a cross sectional view showing a non-contact type
IC card 50 according to still another embodiment of the present
invention.
[0042] FIG. 9 is a cross sectional view showing a non-contact type
IC card 170 according to still another embodiment of the present
invention.
[0043] FIG. 10 is a diagram showing a resonance circuit 150 of an
IC chip module according to still another embodiment of the present
invention.
[0044] FIG. 11 is a diagram showing a resonance circuit 160 of an
IC chip module according to still another embodiment of the present
invention.
[0045] FIG. 12 is a view exemplifying a conventional non-contact
type IC card.
[0046] FIG. 13A is a cross sectional view taken along the line
XIIIA-XIIIA in FIG. 12, and
[0047] FIG. 13B is a circuit diagram of an IC card 2.
BEST MODES FOR CARRYING OUT THE INVENTION
[0048] FIG. 1 is a view showing an overall appearance of
non-contact type IC card 70 as a circuit mounted card according to
one embodiment of the present invention. IC card 70 is a single
coil type IC card which can be used for the gate of the ski lift,
the gate at the station and automatic sorting of parcels and the
like.
[0049] FIG. 2 is a cross sectional view taken along the line II-II
in FIG. 1. IC card 70 has a structure having a surface layer
material 32 of a first base material, a core member 34 forming a
core member layer and a surface layer material 36 of a second base
material, which are stacked in this order. Synthetic resin such as
vinyl chloride, PET (polyethylene terephthalate) or the like is
used for surface layer materials 32 and 36. Core member 34 includes
synthetic resin.
[0050] A cavity 72 is provided in the layer of core member 34. In
cavity 72, an IC chip module 74 is fixed as a circuit chip module
in contact with surface layer material 32.
[0051] FIG. 3A is a front view of IC chip module 74. IC chip module
74 is a composition including an IC chip 76 of a first circuit chip
and an IC chip 78 of a second circuit chip which are stacked in a
direction of thickness (see FIG. 2) of IC card 70 through an
anisotropic conductor 80.
[0052] FIG. 3B shows elements of IC chip module 74 before they are
connected together. IC chip 76 is provided on its top with a
plurality of bumps 82 for terminals. IC chip 78 is provided on its
bottom a plurality of bumps 84 for terminals. Bumps 82 and 84 are
arranged in mutually opposite positions.
[0053] Anisotropic conductor 80 is a conductor having a
conductivity only in one direction and provided with adhesion. As
the anisotropic conductor, anisolum (Hitachi Chemical Co., Ltd.),
which is a thermosetting adhesive, is used. Such anisotropic
conductor 80 enables IC chips 76 and 78 to be firmly adhered.
Adhesion of IC chips 76 and 78 using anisotropic conductor 80
allows bumps 82 and 84 provided in mutually opposite positions to
be electrically connected. Thus, IC chip module 74 is formed.
[0054] FIG. 4 is a schematic diagram showing IC chip 76 when viewed
from above (from the side of bumps 82). IC chip 76 is provided with
a nonvolatile memory (not shown) and a modulating/demodulating
circuit (not shown) which are part of the processing portion and
the like.
[0055] FIG. 5 is a schematic diagram showing IC chip 78 when viewed
from below (from the side of bumps 84). IC chip 78 is provided with
a coil 44 of an antenna, capacitors C1 and C2 which are the
remaining portion of the processing portion and the like. A metal
interconnection layer is configured in a loop like shape to form
coil 44. At least one of capacitors C1 and C2 includes a
ferroelectric substance. In addition, coil 44 and capacitor C1 form
a resonance circuit. Capacitor C2 is used for smoothing a power
supply.
[0056] Such structure enables a communication function to be
achieved simply by stacking IC chips 76 and 78 provided with
functions of the processing portion and the antenna, so that the
interconnection needs not be arranged outside IC chips 76 and 78.
In addition, even if deflection is repeatedly caused for IC card
70, breakage of the external interconnection or accidental
disconnection would not happen.
[0057] Further, a position in which the IC chip is arranged is not
restricted to ensure a space for a coil because coil 44 is included
in IC chip 78 which is stacked on IC chip 76. Thus, IC chips 76 and
78 with a small area when viewed from above can be arranged in an
arbitrary position where a significant deflection would not be
caused. As a result, even if a significant force is applied to IC
card 70, stacked IC chips 76 and 78 would not significantly be
deformed.
[0058] Since the connecting operation of the external
interconnection is eliminated, assembly operation would be
extremely facilitated. Thus, reduction in the manufacturing cost is
achieved. Further, as capacitors C1 and C2 are also included in IC
chip 78, operation for mounting these capacitors C1 and C2 is not
necessary. As a result, further reduction in the manufacturing cost
is achieved.
[0059] A small IC chip module 74 can perform the communication
function. Thus, the elements in IC card 70 are more freely
arranged. Preliminary formed single IC chip module 74 needs only be
handled during assembly, so that further reduction in the
manufacturing cost is achieved with increased workability.
[0060] Next, the detour interconnection, dummy bump and dummy
interconnection used in IC chip module 74 will be described. FIG. 6
is a diagram shown in conjunction with the dummy bump and detour
interconnection.
[0061] For IC chips 76 and 78, bumps 86a to 86e and 88a to 88c
shown in FIG. 6 are provided in addition to bumps 82 and 84 shown
in FIGS. 4 and 5. Further, interconnections 90a, 90b and 92 are
provided. The interconnection shown in FIG. 6 corresponds to the
detour interconnection. Bumps 86e and 88c are dummy bumps.
[0062] Bumps 86a and 86b provided for IC chip 76 are connected by
an interconnection 90a provided for IC chip 76. Bumps 86c and 86d
are connected by an interconnection 90b provided inside IC chip 76.
On the other hand, bumps 88a and 88b provided for IC chip 78 are
connected by an interconnection 92 provided inside IC chip 78.
[0063] Bump 86b provided for IC chip 76 and bump 86a provided for
IC chip 78 are arranged in opposite positions. Similarly, bump 86c
provided for IC chip 76 and bump 86a provided for IC chip 78 are
arranged in opposite positions.
[0064] Thus, when IC chips 76 and 78 are connected through
anisotropic conductor 80 (see FIG. 3B), bump 86a provided for IC
chip 76 is connected to bump 86d through interconnection 90a, bump
86b, bump 88a, interconnection 92, bump 88b bump 86c and
interconnection 90b.
[0065] With such structure, IC card 70 would not perform an
essential function unless two IC chips 76 and 78 are connected.
Thus, even if IC chip module 74 is to be divided into two IC chips,
it is difficult to analyze the function by each terminal.
[0066] Although bump 86e provided for IC chip 76 and bump 88c
provided for IC chip 78 are arranged in opposite positions, they
are dummy bumps which are not electrically connected to any other
element. Further, the interconnection (not shown) which is not
connected to any element other than bumps may be provided. This is
called a dummy interconnection.
[0067] Provision of a plurality of such detour interconnection,
dummy bumps and dummy interconnections makes it more difficult to
analyze the function. In other words, an IC chip module with high
security is achieved. In addition, an IC card with high security is
achieved by inclusion of such IC chip module 74.
[0068] It is noted that thicknesses of surface layer materials 32
and 36 are both 0.1 mm and an overall thickness of IC card 70 is
0.768 mm. Each of IC chips 76 and 78 is square in shape having a
side of 3 mm, an internal thickness of the IC chip is 0.2 mm, and
thicknesses of bumps 82 and 84 are both 0.11 mm. A thickness of IC
chip module 74 after connection is about 0.55 mm. It is noted that
the present invention is not limited to these dimensions and
materials.
[0069] An operation of IC card 70 is similar to that of
conventional IC card 2. In other words, an electromagnetic wave
transmitted from a reader/writer (writing/reading apparatus, not
shown) is received by a resonance circuit (not shown) formed of
coil 44 and capacitor C1 included in IC chip 78 as a power source.
The received power is smoothed by capacitor C2.
[0070] The information transmitted by the electromagnetic wave is
decoded by a control portion (not shown) provided in IC chip 76 for
response. The response is performed by changing an impedance of the
resonance circuit. The reader/writer obtains a content of the
response by detecting a change in an impedance of its own resonance
circuit (not shown) due to the change in the impedance of the
resonance circuit of IC card 77.
[0071] Thus, information is transmitted and received in a
non-contact state without providing a power supply source in the
card.
[0072] It is noted that although IC chips 76 and 78 are connected
together in a stack with anisotropic conductor 80 interposed in the
above embodiment, IC chips 76 and 78 may be directly connected
without anisotropic conductor 80 interposed. In this case, for
example, one of bumps 82 and 84 may be formed of gold (Au) and the
other of tin (Su), so that they are connected by utilizing
eutectic. Thus, two IC chips 76 and 78 can readily be connected to
form a module using a conventional technique of connecting
terminals.
[0073] In addition, in the above described embodiment, although at
least one of capacitors C1 and C2 is formed of a ferroelectric
substance, all of the capacitors may be formed of general
dielectric capacitors.
[0074] Although an antenna included in IC chip 78 corresponds to
coil 44 formed on metal interconnection layer 6, the antenna is not
limited to such configuration. Further, although capacitors C1 and
C2 are both formed in IC chip 78, the coil and capacitor may be
formed in different IC chips.
[0075] FIG. 7 is a cross sectional view showing a non-contact type
IC card 30 as a circuit chip mounted card according to another
embodiment of the present invention. The appearance of IC card 30
is almost the same as that of IC card 70. Further, IC chip module
74 looks almost the same as that in the case of IC card 70. Thus,
the operation of IC card 30 is similar to that of IC card 70.
[0076] As shown in FIG. 7, IC card 30 includes a surface layer
material 32 of a first base material, a core member 34 and a
surface layer material 36 of a second base material, which are
stacked in this order. Synthetic resin such as vinyl chloride, PET
(polyethylene terephthalate) or the like is used. In addition, core
member 34 is formed of synthetic resin.
[0077] A ceramic frame 38 is provided in the layer of core member
34. Ceramic frame 38 includes ceramic in a cylindrical shape.
Ceramic frame 38 corresponds to a frame of a reinforcing member. In
other words, the reinforcing member includes only a frame in the
present embodiment.
[0078] Internal portion 38a of ceramic frame 38 is a cavity. An
elastic material 40 is provided as a shock absorbing material at a
lower end of internal portion 38a of ceramic frame 38 in contact
with surface layer material 32. Silicon rubber provided with
adhesion is used as elastic material 40. IC chip module 74 as a
circuit chip module is supported by elastic material 40.
[0079] As the reinforcing member includes ceramic, high rigidity is
ensured. Thus, provision of ceramic frame 38 in the layer formed of
core member 34 greatly increases bending, twisting and pressing
rigidity of IC card 30 in vicinity of ceramic frame 38.
[0080] As a result, even if a significant bending, twisting and
pressing force or the like is applied to IC card 30, IC chip module
74 provided in internal portion 38a of ceramic frame 38 would not
significantly be deformed. Thus, even if a bending, twisting,
pressing force or the like is applied, it is unlikely that IC chip
module 74 would be damaged. In other words, IC card 30 is provided
with higher reliability.
[0081] Further, since IC chip module 74 is fixed with elastic
material 40 interposed, even when a shock is applied to IC card 30,
it is not directly transferred to IC chip module 74. Thus, damage
of IC chip module 74 due to the shock is reduced.
[0082] It is noted that thicknesses of surface layer materials 32
and 36 are both 0.1 mm and an overall thickness of IC card 30 is
0.768 mm in the present embodiment. In addition, IC chip module 74
is a square having a side of 3 mm. It is noted that a thickness of
IC chip module 74 is set to about 0.4 mm unlike the above described
embodiment.
[0083] A thickness of elastic material 40 is 0.118 mm. A height of
ceramic frame 38 is 0.568 mm. An inner diameter of ceramic frame 38
is set such that a clearance with respect to the mounted IC chip
module 74 is about 0.2 mm to 0.3 mm. Further, an outer diameter of
ceramic frame 38 is about 23 mm. It is noted that the present
invention is not limited to these dimensions and materials.
[0084] In the present embodiment, IC chip module 74 is fixed to
surface layer material 32 with elastic material 40 as shown in FIG.
7. However, IC chip module 74 may directly be fixed to surface
layer material 32 without elastic material 40 interposed.
[0085] FIG. 8 is a cross sectional view showing a non-contact type
IC card 50 as a circuit chip mounted card according to still
another embodiment of the present invention. An overall structure
of IC card 50 is similar to that of IC card 30.
[0086] In IC card 50, however, ceramic frame 52 is different from
ceramic frame 38 of IC card 30 in shape as shown in FIG. 8. More
specifically, ceramic frame 52 is different from ceramic frame 38
formed of only a frame in a cylindrical shape in that it includes a
cylindrical portion 52a of a frame and a plate like bottom portion
52b integrated with the lower end of cylindrical portion 52a.
[0087] Further, as shown in FIG. 8, IC chip module 74 is structured
to be directly fixed to bottom portion 52b of a recessed space 52c
defined by cylindrical portion 52a and bottom portion 52b of
ceramic frame 52.
[0088] Thus, as bottom portion 52b is integrated with the lower end
of cylindrical portion 52a, ceramic frame 52 is provided with
higher rigidity. Thus, even when ceramic frame 52 is increased in
size in face directions (X and Y directions in FIG. 1) to some
extent, desired rigidity is ensured. Accordingly, the dimension of
IC chip module 74 is increased. Therefore, a dimension of coil 44
included in IC chip module 74 is further increased.
[0089] As shown in FIG. 8, frame module 54 is formed with ceramic
frame 52 and IC chip module 74 fixed to ceramic frame 52. Such
module enables increase in workability during manufacture and
reduction in the manufacturing cost.
[0090] Although IC chip module 74 is structured to be directly
fixed to bottom portion 52b of ceramic frame 52 in the present
embodiment, elastic material 40 as shown in FIG. 7 may be
interposed between IC chip module 74 and bottom portion 52b of
ceramic frame 52. Such structure reduces the shock applied to the
card.
[0091] FIG. 9 is a cross section showing a non-contact type IC card
170 as a circuit chip mounted card according to still another
embodiment of the present invention. An overall appearance of IC
card 170 is similar to that of IC card 30.
[0092] As shown in FIG. 9, ceramic frame 172 of IC card 170 is
different from ceramic frame 38 of IC card 30 in shape. More
specifically, although ceramic frame 170 is formed in a single
cylinder shape similar to outer ceramic frame 38, it is different
from ceramic frame 38 in that the inner portion thereof is formed
in a stepped cylinder shape.
[0093] As shown FIG. 9, a support film 174 of a shock absorbing
member is adhered to a stepped portion 172a of ceramic frame 172.
Support film 174 is a film of synthetic resin formed in a hollow
disk like shape. Thus, support film 174 is supported by stepped
portion 172a of ceramic frame 172 in internal space 172b of ceramic
frame 172 in a floating state.
[0094] IC chip module 74 is adhered to almost the middle portion of
support film 174. Thus, IC chip module 74 is supported by support
film 174 in internal space 172b of ceramic frame 172 in a floating
state.
[0095] Such structure further ensures that the shock applied to the
card is reduced. In addition, as shown in FIG. 9, ceramic frame
172, support film 174 and IC chip module 74 form a frame module
176. Such module enables increase in workability during manufacture
and reduction in the manufacturing cost.
[0096] Although the film of synthetic resin in a hollow disk like
shape is used as the shock absorbing member, the shape and material
of shock absorbing member is not limited to this.
[0097] Further, although a cylinder with no base or with base is
used for the reinforcing member, inner and outer shapes of the
cylinder are not limited to such cylinder. For example, the
reinforcing member may assume a hollow square pole. The reinforcing
member is not limited to the cylinder, and may assume a shape of a
disk. Further, a plurality of reinforcing members may be provided.
For example, reinforcing members may be provided on and under the
circuit chip to sandwich the same.
[0098] Although the reinforcing member includes ceramic in the
aforementioned embodiment, a material other than ceramic may be
employed as long as it is provided with high rigidity. For example,
a metal material such as stainless steel, hard synthetic resin or
the like may be used.
[0099] An IC chip module as a circuit chip module according to
still another embodiment of the present invention will be
described. The IC chip module is similar to IC chip module 74 shown
in FIG. 3. It is noted that although the resonance circuit of IC
chip module 74 shown in FIG. 3 is similar to resonance circuit 22
shown in FIG. 13B, a resonance circuit of the IC chip forming the
IC chip module according to the present embodiment corresponds to a
resonance circuit 150 shown in FIG. 10 and is different.
[0100] Resonance circuit 150 is connected as shown in FIG. 10 and
includes a capacitor portion 152 having five capacitors C1 to C5
and five laser taps T1 to T5, and a coil L. Capacitors C1 to C5 are
respectively connected in parallel through laser taps T1 to T5 in
capacitor portion 152. Laser taps T1 to T5 are provided with
conductivity and can be disconnected by illumination of laser.
[0101] A combined capacitance of capacitor portion 152 can be
adjusted by disconnecting a suitable one of laser taps T1 to T5.
The adjustment of the combined capacitance of capacitor portion 152
allows a resonance frequency of resonance circuit 150 to be
adjusted. It is noted that the disconnection of laser taps T1 to T5
is performed in a step subsequent to formation of capacitors C1 to
C5 and coil L in the IC chip and the like.
[0102] For example, the resonance frequency is measured while
sequentially disconnecting laser taps T1 to T5 and, when the
resonance frequency is attained to a prescribed threshold value,
the disconnection is stopped.
[0103] In addition, when there is little variation in the IC chips
which have been manufactured in the same process, an optimum
disconnection pattern is found using the IC chip of a test sample,
so that laser taps T1 to T5 are subsequently disconnected with the
same disconnection pattern for the IC chips manufactured in the
same process.
[0104] When there are a plurality of kinds of IC chips, a resonance
frequency differs in kind of the IC chip can be set by changing the
disconnection pattern for laser taps T1 to T5 for every kind of the
IC chip.
[0105] All of the capacitances of capacitors C1 to C5 may be same
or different. For example, capacitances of capacitors C1 to C5 may
be 1 .mu.F, 2 .mu.F, 4 .mu.F, 8 .mu.F and 16 .mu.F, respectively.
This allows the combined capacitance to be adjusted between 1 .mu.F
and 31 .mu.F by 1 .mu.F. It is noted that the number of capacitors
or laser taps is not limited to five.
[0106] A resonance circuit 160 shown in FIG. 11 may be used in
place of resonance circuit 150 shown in FIG. 10. Resonance circuit
160 is connected as shown in FIG. 11 and includes a coil portion
162 including six coils L1 to L6 and five laser taps T1 to T5, and
a capacitor C. Coils L1 to L6 are connected in series in coil
portion 162, the connection point of each coil is structured to be
short-circuited through laser taps T1 to T5.
[0107] By disconnecting laser taps T1 to T5 in this order, a
combined inductance of coil portion 162 can be adjusted. The
adjustment of the combined inductance of coil portion 162 allows
the resonance frequency of resonance circuit 160 to be adjusted. It
is noted the number of coils or laser taps is not limited to
five.
[0108] The resonance circuit which allows adjustment of the
resonance frequency is not limited to these circuits. For example,
resonance circuit 150 in FIG. 10 and resonance circuit 160 in FIG.
11 may be combined to form a resonance circuit.
[0109] Thus, as the resonance frequency of the resonance circuit
can be adjusted, the capacitance or inductance of the resonance
circuit can be adjusted after formation of the capacitor and coil
in the IC chip. As a result, although circuit elements forming the
resonance circuit are all formed in the IC chip, the resonance
frequency can be adjusted after these circuit elements are
formed.
[0110] More specifically, as the resonance frequency is maintained
at a prescribed level to some extent even when there is variation
in the manufacturing conditions, the IC card including such IC chip
is provided with higher reliability. Further, since the IC chip
corresponding to various resonance frequencies can be obtained
without changing a mask pattern for forming the circuit elements in
the manufacturing process of the IC chip, reduction in the
manufacturing cost is achieved.
[0111] It is noted that although the coil which is formed in a loop
like shape is used as an antenna in the above described
embodiments, the configuration of the antenna is not limited to
this. For example, a metal line in a linear or meander shape may be
used.
[0112] Although the present invention has been exemplified as being
applied to the non-contact type IC card with a single coil in the
above embodiments, the present invention may also be applied to a
non-contact type IC card with a plurality of coils. Further, the
present invention can be applied not only to the IC card but also
to a general module or card with a circuit chip. The card herein
corresponds to a member in a general disk like shape, and includes
a credit card, pass and ticket for railroad, and the like.
* * * * *