U.S. patent application number 12/963013 was filed with the patent office on 2011-04-28 for pattern forming system, pattern forming method, and electronic apparatus.
This patent application is currently assigned to SEIKO EPSON CORPORATION. Invention is credited to Kazuaki SAKURADA, Tsuyoshi SHINTATE, Noboru UEHARA.
Application Number | 20110097515 12/963013 |
Document ID | / |
Family ID | 36205794 |
Filed Date | 2011-04-28 |
United States Patent
Application |
20110097515 |
Kind Code |
A1 |
SAKURADA; Kazuaki ; et
al. |
April 28, 2011 |
PATTERN FORMING SYSTEM, PATTERN FORMING METHOD, AND ELECTRONIC
APPARATUS
Abstract
A pattern forming system including a feeding reel for feeding a
tape form substrate that is wound up, a winding reel for winding up
the tape form substrate that is fed up, and a droplet discharge
apparatus for discharging a droplet onto the tape form substrate,
between the feeding reel and the winding reel, to form a pattern,
wherein the droplet discharge apparatus includes a table that can
move while sucking the tape form substrate, with a slack mechanism
for the tape form substrate being placed on the both ends of the
table in the longitudinal direction of the tape form substrate.
Inventors: |
SAKURADA; Kazuaki;
(Suwa-shi, JP) ; UEHARA; Noboru; (Okaya-shi,
JP) ; SHINTATE; Tsuyoshi; (Matsuyama-machi,
JP) |
Assignee: |
SEIKO EPSON CORPORATION
Tokyo
JP
|
Family ID: |
36205794 |
Appl. No.: |
12/963013 |
Filed: |
December 8, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12232715 |
Sep 23, 2008 |
7871666 |
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|
12963013 |
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|
11218545 |
Sep 6, 2005 |
7462241 |
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12232715 |
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Current U.S.
Class: |
427/558 ;
427/177 |
Current CPC
Class: |
H05K 2203/013 20130101;
H05K 2203/082 20130101; H05K 1/0393 20130101; H05K 2203/1545
20130101; B41J 15/005 20130101; H05K 2203/0165 20130101; B41J 11/44
20130101; H05K 3/125 20130101; B41J 11/0085 20130101 |
Class at
Publication: |
427/558 ;
427/177 |
International
Class: |
B05D 3/06 20060101
B05D003/06; B05D 3/12 20060101 B05D003/12 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 27, 2004 |
JP |
2004-312233 |
Claims
1. A droplet discharge method that winds a flexible substrate fed
from a feeding reel by a winding reel, and discharges a droplet
from a droplet discharge head onto the flexible substrate between
the feeding reel and the winding reel, comprising: fixing the
flexible substrate against a table on which the flexible substrate
is mounted; and discharging the droplet from the droplet discharge
head to the flexible substrate in a state in which the flexible
substrate is fixed against the table.
2. The droplet discharge method as set forth in claim 1, further
comprising: adjusting a position of the flexible substrate with
respect to the droplet discharge head by moving the table before
discharging the droplet.
3. The droplet discharge method as set forth in claim 2, a
direction in which the table moves being a direction in which the
flexible substrate is conveyed.
4. The droplet discharge method as set forth in claim 1, in the
discharging a droplet, as the droplet, a UV hardening material
being discharged from the droplet discharge head.
5. The droplet discharge method as set forth in claim 4, further
comprising: hardening the droplet by irradiating UV [light] to the
droplet discharged to the flexible substrate.
6. The droplet discharge method as set forth in claim 1, in the
fixing the flexible substrate against the table, first and second
rollers pressing the flexible substrate against the table by
pressing the first roller, which is arranged on one side, and the
second roller, which is arranged on another side, with the table
sandwiched therebetween, in the direction in which the flexible
substrate is conveyed.
7. The droplet discharge method as set forth in claim 1, the table
having an adsorption function that adsorbs the flexible substrate.
Description
[0001] This is a Continuation of application Ser. No. 12/232,715
filed Sep. 23, 2008, which is a Division of application Ser. No.
11/218,545 filed Sep. 6, 2005 (now U.S. Pat. No. 7,462,241 issued
Dec. 9, 2008). The disclosure of the prior applications is hereby
incorporated by reference herein in its entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Technical Field
[0003] The present invention relates to a pattern forming system, a
pattern forming method, and an electronic apparatus.
[0004] 2. Related Art
[0005] Lithography, for example, is used for the manufacturing of
wirings that are used in electronic circuits or integrated
circuits. Lithography requires huge facilities, such as a vacuum
system, and complicated processes. Besides, in the case of using
lithography, the manufacturing cost is high because the yield rate
is only a few percent and the bulk of material must be thrown out.
Therefore, as an alternative process to lithography, a method of
patterning a droplet containing a functional material directly onto
a substrate by an ink jet (a droplet discharge system) is
considered. For example, a method wherein a droplet in which
conductive microparticles are dispersed is applied and patterned
directly onto a substrate by a droplet discharge system and then
transformed into a conductive film pattern by heat treatment and
laser irradiation is proposed (refer, for example, to the
specification of the U.S. Pat. No. 5,132,248).
[0006] Further, a method that can be flexibly adjusted to the kind
of manufacturing process to be applied in the manufacturing method
of a display unit and a display device using a droplet discharge
system is proposed. The method, when a relative velocity of an ink
jet head to a substrate is defined as V, a discharge period of
droplets as T, and a diameter of the droplets after the droplets
land on the substrate and expand to wet as D, controls the relative
velocity V, the discharge period T and the diameter D so as to
satisfy the relation VT<D. Then, droplets are discharged on a
substrate on the most appropriate discharging condition according
to the kind of manufacturing process to be applied (refer, for
example, to Japanese Patent Application Publication
2003-280535).
[0007] However, in the manufacturing methods of wirings or display
devices according to the above-referenced methods, a platy
substrate is processed into a product substrate using a plurality
of steps. Therefore, a substrate needs to be moved sequentially
from a location (a device) on which a certain step to be carried
out to another location on which a next step to be carried out.
Thus, in the above-referenced manufacturing methods, there is a
problem that manufacturing cost increases because a large amount of
labor and mechanism is required to transfer substrates.
Specifically, in the above-referenced manufacturing methods, a
large amount of labor and a complex moving mechanism such as a
robot is required for allocating a surface treatment apparatus, a
droplet discharge apparatus, and a drying apparatus and the like
and for transferring substrates sequentially toward each of the
apparatuses and aligning them precisely.
[0008] Therefore, a pattern forming system that uses a reel-to-reel
substrate in tape form, each end of which is wound up with reels,
and that carries out a plurality of steps, including a droplet
applying step by a droplet discharge system, from the feeding of a
tape form substrate until the winding up of the tape form substrate
is considered. According to the system, patterns can be simply and
easily formed on a plurality of pattern forming areas on a tape
form substrate by first carrying out a droplet applying step to one
pattern forming area and then winding up the tape form substrate to
place the next pattern forming area for the droplet applying step.
Finally, the tape form substrate is cut off for each pattern
forming area. Thus, wirings and electronic circuits can be
efficiently manufactured in volume.
[0009] However, pulling strength is generated in the longitudinal
direction because the tape form substrates are formed successively
in the longitudinal direction with each end wound up with reels.
Therefore, there is a problem that the position adjustment of a
tape form substrate during a droplet applying step and the like is
difficult. Especially, position adjustments, such as moving a tape
form substrate in the lateral direction or slewing a tape form
substrate around a normal line, have to be done coping with the
pulling strength that is generated in the longitudinal direction.
Thus, it is difficult to form a pattern on a precise position.
SUMMARY
[0010] An advantage of the present invention is to provide a
pattern forming system and a pattern forming method that can
facilitate a position adjustment of a tape form substrate to form a
precise pattern. Another advantage is to provide an electronic
apparatus that is highly reliable and has a precise pattern.
[0011] Therefore, a first aspect of the invention is to provide a
pattern forming system that includes a feeding reel for feeding a
tape form substrate that is wound up, a winding reel for winding up
the tape form substrate that is fed up, and a droplet discharge
apparatus for discharging a droplet onto the tape form substrate,
between the feeding reel and the winding reel, to form a pattern.
The droplet discharge apparatus includes a table that can move
while sucking the tape form substrate. A slack mechanism for the
tape form substrate is placed on the both ends of the table in the
longitudinal direction of the tape form substrate. According to the
configuration, the pulling strength generated in the longitudinal
direction of the tape form substrate is dissolved because a slack
mechanism for the tape form substrate is placed. By moving, in this
state of things, the table that sucks the tape form substrate, the
position of the tape form substrate can be adjusted. Thus, a
pattern forming system capable of forming a precise pattern is
provided.
[0012] It is preferable that the slack mechanism is configured in a
manner of swagging the tape form substrate between a pair of
movable rollers that are placed at a certain distance. According to
the configuration, a slack mechanism can be configured easily and
at a low rate.
[0013] It is also preferable that the table on the droplet
discharge apparatus is configured so as to at least be able to slew
around a normal line of the suction surface of the tape form
substrate. According to the configuration, the position of the tape
form substrate sucked on the table can be adjusted around the
normal line.
[0014] It is also preferable that the ink jet head of the droplet
discharge apparatus is configured so as to at least be able to scan
within the parallel surface of the suction surface of the tape form
substrate on the table. According to the configuration, patterns
can be formed by discharging a droplet onto any given position of
the tape form substrate sucked on the table.
[0015] It is also preferable that the slack mechanism has a fixed
roller that can interpose the tape form substrate between one of
the paired movable rollers, the one that is placed closer to the
table. The configuration can prevent the slack of the tape form
substrate in the slack mechanism from affecting the table,
stabilizing the position of the tape form substrate on the table.
Thus, a precise pattern can be formed.
[0016] It is also preferable that the slack mechanism has a pulling
roller that can bring out pulling strength in the longitudinal
direction of the tape form substrate. According to the
configuration, pulling strength can be easily brought out to the
tape form substrate and the tape form substrate after the pattern
forming step can be wound up.
[0017] Meanwhile, a second aspect of the invention is to provide a
pattern forming method using a pattern forming system that includes
a feeding reel for feeding a tape form substrate that is wound up,
a winding reel for winding up the tape form substrate that is fed
up, and a droplet discharge apparatus for discharging a droplet
onto the tape form substrate, between the feeding reel and the
winding reel, to form a pattern. The pattern forming method
includes letting the tape form substrate that is sucked on the
table placed on the droplet discharge apparatus, dissolving the
pulling strength generated in the longitudinal direction of the
tape form substrate, adjusting the position of the tape form
substrate by moving the table, and forming a pattern by discharging
a droplet on the tape form substrate by the droplet discharge
apparatus. According to the configuration, the position controlling
of the tape form substrate can be facilitated and a precise pattern
can be formed.
[0018] It is preferable that the pattern forming method includes,
after forming a pattern by discharging a droplet onto the tape form
substrate, releasing the suction of the tape form substrate by the
table, bringing out pulling strength in the longitudinal direction
of the tape form substrate, and winding up the tape form substrate
by the winding reel. According to the configuration, a tape form
substrate after a pattern is formed can be wound up easily.
[0019] Meanwhile, an electronic apparatus of the invention is
manufactured using the above-referenced pattern forming system.
According to the configuration, a highly reliable electronic
apparatus can be provided because the configuration allows a
precise pattern to be generated.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The invention will be described with reference to the
accompanying drawings, wherein like numbers refer to like elements,
and wherein:
[0021] FIG. 1 is a pattern diagram schematically showing a pattern
forming system according to an embodiment of the invention;
[0022] FIG. 2 is a diagram schematically showing a wiring drawing
step;
[0023] FIG. 3 is an oblique diagram of a droplet discharge
apparatus;
[0024] FIG. 4 is a flowchart of detailed processes of a wiring
drawing step;
[0025] FIGS. 5A and 5B are diagrams explaining an ink jet head;
[0026] FIGS. 6A and 6B are diagrams explaining a wiring
pattern;
[0027] FIG. 7 is an operation sheet of a wiring pattern forming
method;
[0028] FIG. 8 is an exploded oblique diagram of a liquid crystal
module with a COF structure; and
[0029] FIG. 9 is an oblique diagram of a cellular phone.
DESCRIPTION OF THE EMBODIMENTS
[0030] A pattern forming system and a pattern forming method
according to the embodiments of the invention will now be described
with reference to the drawings. A pattern forming method according
to the embodiments of the invention can be carried out by using a
pattern forming system according to the embodiments of the
invention. Here, a pattern forming system and a pattern forming
method for forming a wiring composed of a conductive film on a tape
form substrate constituting a reel-to-reel substrate will be
described as an example.
A Pattern Forming System
[0031] FIG. 1 is a pattern diagram schematically showing a pattern
forming system and a pattern forming method according to an
embodiment of the invention. The pattern forming system is composed
at least of a feeding reel 10 where a tape form substrate 11 is
wound up and a winding reel 15 for winding up a tape form substrate
11 that is fed out from the feeding reel 10.
[0032] A zonal flexible substrate, for example, is applied as a
tape form substrate 11, using polyimide and the like as a backing
material. As a concrete example of a tape form substrate 11, the
width may be set to be 105 mm and the length to be 200 mm. The tape
form substrate 11 constitutes a reel-to-reel substrate, the both
edges of its zonal shape being respectively wound up by the feeding
reel 10 and the winding reel 15. Specifically, the tape form
substrate 11 fed out from the feeding reel 10 is wound up by the
winding reel 15, moving successively in the longitudinal direction
(in the feeding direction of the tape form substrate 11).
[0033] The pattern forming system includes a plurality of
apparatuses that carries out a plurality of steps one by one onto
the reel-to-reel substrate composed of a piece of a tape form
substrate 11. A cleaning step, a surface treatment step, an
insulating film drawing step, an insulating film hardening step, a
wiring drawing step, a wiring hardening step and the like are
included in the plural steps. Through these steps, a wiring and an
insulating film and the like can be generated on the tape form
substrate 11.
[0034] In the pattern forming system, a number of desired substrate
forming areas (hereinafter, simply referred to as a "unit area")
are set up at a predetermined interval in the longitudinal
direction of the tape form substrate 11. Then, the tape form
substrate 11 is moved successively to each of the apparatuses in
each of the steps to successively form wiring layers and insulating
layers and the like on each of the unit areas on the tape form
substrate 11. Specifically, the above-referenced plural steps are
carried out on an assembly line, each of the steps being carried
out simultaneously or on overlapped timing on the plural
apparatuses.
[0035] According to the pattern forming system, wirings and
electronic circuits and the like can be manufactured efficiently
and in volume because patterns (wirings, for example) are generated
by using a droplet discharging system onto a tape form substrate
constituting a reel-to-reel substrate. For example, a unit area on
a tape form substrate can be transferred from an apparatus on which
a certain step to be carried out to a next apparatus on which a
next step to be carried out only by winding up one edge of the tape
form substrate. Therefore, according to the invention, transport
mechanism and alignment mechanism for transferring a substrate to
each apparatus for each step can be simplified, which lowers the
manufacturing cost in the case of volume production or the
like.
[0036] FIG. 2 is a diagram schematically showing a wiring drawing
step in the pattern forming system. A droplet discharge apparatus
20 is set up in the wiring drawing step. FIG. 3 is an oblique
diagram of a droplet discharge apparatus. The droplet discharge
apparatus 20 is mainly composed of a table 4 on which a tape form
substrate 11 to be placed and an ink jet head 30 for discharging a
droplet onto the tape form substrate 11. The surface of the table 4
on which the tape form substrate 11 to be placed is formed larger
at least than a unit area 11a on the tape form substrate 11. A
suction unit 4b, such as a vacuum suction apparatus, is placed on
the surface of the table 4 so as to be able to suck the placed tape
form substrate 11. A motor 4a is placed beneath the table 4. The
motor 4a is used to slew the table 4 around the normal line
direction of the table 4 (in the .theta. direction). Thus, the
position of the tape form substrate 11 that is sucked on the
surface of the table 4 can be adjusted in the .theta.
direction.
[0037] Meanwhile, the ink jet head 30 is configured so as to be
able to move in the longitudinal direction (in the Y direction) of
the tape form substrate 11 along a guide 5 that is placed on the
undersurface of an arm 3. The arm 3 is configured so as to be able
to move in the lateral direction (in the X direction) of the tape
form substrate 11 along a guide 2 that is placed at a certain
height from a pedestal 7. Thus, an ink jet head 30 can move
unrestrainedly within the XY flat surface at a certain height from
the tape form substrate 11, allowing a droplet to be discharged
onto any predetermined position within a unit area 11a on the tape
form substrate 11. Further, it is preferable that the ink jet head
30 not only can move in the X and Y directions as well as in the Z
direction (in the normal line direction of the tape form substrate
11) but also can slew around the X, Y and Z axes. The inner
structure and behavior of the ink jet head 30 will be described
later in detail.
[0038] Going back to FIG. 2, slack mechanisms 50 and 60 for the
tape form substrate 11 are set up on the each end of the table 4 in
the longitudinal direction of the tape form substrate 11. Although
the slack mechanism 60 that is placed downstream of the wiring
drawing step will be now described, the slack mechanism 50 that is
placed upstream works just in the same way. The slack mechanism 60
includes a pair of movable rollers 62 and 64 that are placed
parallel at a predetermined interval in the horizontal direction.
The central axes of the movable rollers 62 and 64 are placed almost
vertically to the longitudinal direction of the tape form substrate
11. The tape form substrate 11 is swagged between the paired
movable rollers 62 and 64, constituting the slack mechanism 60 for
the tape form substrate 11. Thus, the pulling strength that affects
the tape form substrate 11 is dissolved by the slack mechanism 60
that is configured easily and at a low rate.
[0039] Within the tape form substrate 11 that is swagged between
the paired movable rollers 62 and 64, a pulling roller 66 is placed
parallel to the movable rollers 62 and 64. The pulling roller 66 is
configured so as to be able to move up and down. Then, the slack of
the tape form substrate 11 is dissolved by moving downward the
pulling roller 66 to press the swagged tape form substrate 11 from
inside to outside. Thus, pulling strength can be brought out in the
longitudinal direction of the tape form substrate 11 in the feeding
of the tape form substrate 11. The tape form substrate 11 can be
fed by winding up, in this state of things, the tape form substrate
11 with the winding reel 15.
[0040] Above the movable roller 62, that is closer to the table 4,
of the paired movable rollers 62 and 64, a fixed roller 68 is
placed parallel to the movable rollers 62. The fixed roller 68 is
also configured so as to be able to move up and down. Then, by
moving downward the fixed roller 68, the tape form substrate 11 is
interposed between the movable rollers 62. Thus, the slack of the
tape form substrate in the slack mechanism 60 can be prevented from
affecting the table 4, stabilizing the position of the tape form
substrate 11 on the table 4 during the droplet discharging.
A Pattern Forming Method
[0041] FIG. 4 is a flowchart of detailed processes of a wiring
drawing step. Now, each of the detailed processes shown in FIG. 4
will be described using a diagram in FIG. 2 that schematically
shows a wiring drawing step.
[0042] First, a tape form substrate is fed to a predetermined
position (Step 702). Specifically, a unit area on the tape form
substrate 11 on which a wiring to be formed is moved onto the table
4 in the wiring drawing step by feeding the tape form substrate 11
from the feeding reel 10 and winding up with the winding reel 15.
Then, the tape form substrate 11 is sucked by a suction unit placed
on the table 4 (Step 704). Thus, the relative position of the unit
area on the tape form substrate 11 to the table 4 is fixed.
[0043] Then, the amount of the position adjustment of the tape form
substrate 11 is decided (Step 706). In the peripheral part of the
unit area of the tape form substrate 11, alignment marks are
precedently drawn and formed by using technologies such as photo
lithography. The current position of the unit area is detected by
picking up the image of the alignment marks using a CCD camera (not
shown) or the like. Next, the amount of displacement of the current
position to the predetermined position on the unit area in the
.theta. direction is calculated. Then, the calculated amount of
displacement is defined as an amount of the position
adjustment.
[0044] Then, the pulling strength in the longitudinal direction of
the tape form substrate 11 is dissolved (Step 708). The dissolving
of the pulling strength is carried out by slacking off the tape
form substrate 11 on the slack mechanisms 50 and 60 that are set up
on the both ends of the table 4. In the above-referenced feeding
step of the tape form substrate 11 (Step 702), the pulling roller
66 is pressed toward the tape form substrate 11, giving pulling
strength in the longitudinal direction of the tape form substrate
11. The pulling roller 66 is moved upward to slack off the tape
form substrate 11, dissolving the pulling strength in the
longitudinal direction of the tape form substrate 11. The slack
mechanisms 50 works just in the same way.
[0045] Next, the position of the tape form substrate 11 is adjusted
(Step 710). Specifically, in accordance with the position
adjustment amount that is calculated in Step 706, the table 4 is
slewed around in the .theta. direction with a motor 4a. In so
doing, the tape form substrate 11 that is sucked on the table 4 can
be moved, following the slewing of the table 4, for only a
predetermined amount in the .theta. direction, because the pulling
strength in the longitudinal direction of the tape form substrate
11 is dissolved by the slack mechanisms 50 and 60 on the both ends
of the table 4. Thus, the unit area of the tape form substrate 11
can be placed on a predetermined position.
[0046] Next, the tape form substrate 11 is fixed at the edge of the
table 4 (Step 712). At the slack mechanism 60, for example, the
fixed roller 68 is moved downwards toward the movable roller 62
that is closer to the table 4 to interpose the tape form substrate
11 between the movable roller 62 and the fixed roller 68. Thus, the
slack of the tape form substrate in the slack mechanism 60 can be
prevented from affecting the table 4, stabilizing the position of
the tape form substrate 11 on the table 4.
[0047] Then, a wiring is drawn with a droplet discharge method
(Step 720). A wiring is formed on a unit area by discharging a
droplet containing a forming material of a wiring while scanning an
ink jet head 30 within the parallel surface of the tape form
substrate 11, details of which will be described later. In the
embodiment, the position adjustment of the tape form substrate 11
in the .theta. direction is carried out by slewing the table 4 as
described above, while the position adjustment in the X and Y
directions is carried out by adjusting the amount of transferring
the ink jet head 30. However, all the position adjustments in each
direction can be carried out on the table 4, in the case, for
example, of forming the table 4 so as to be able to move not only
in the .theta. direction but also in the X and Y directions.
[0048] Next, the fixation of the tape form substrate 11 on the edge
of the table 4 is released (Step 732). For example, at the slack
mechanism 60, the interposing of the tape form substrate 11 is
released by alienating the fixed roller 68 from the movable roller
62 that is closer to the table 4. Next, the suction of the tape
form substrate 11 by the table 4 is released (Step 734). Thus, the
tape form substrate 11 is freed from the restraint by the table 4
and the like, returning on the straight line connecting the feeding
reel 10 and the winding reel 15.
[0049] Next, pulling strength is generated in the longitudinal
direction of the tape form substrate 11 (Step 736). For example, at
the slack mechanism 60, the tape form substrate 11 is pressed by
moving downwards the pulling roller 66 to make the slacked tape
form substrate 11 strained, giving pulling strength in the
longitudinal direction of the tape form substrate 11. The slack
mechanisms 50 works just in the same way. Then, the tape form
substrate 11 is fed to the next step (Step 738). The tape form
substrate 11 can be fed by slewing the winding reel because pulling
strength is given to the tape form substrate 11, as described
above. Thus, the unit area on the tape form substrate 11 on which a
wiring drawing step is finished is fed to the next step.
[0050] As described above, the pattern forming system of the
embodiment includes a droplet discharge apparatus, which is placed
between a feeding reel and a winding reel of a tape form substrate,
for discharging a droplet onto the tape form substrate to form a
pattern. The droplet discharge apparatus includes a table that
sucks a placed tape form substrate and can adjust the position of
the tape form substrate, with a slack mechanism for the tape form
substrate being placed on the both ends of the table in the
longitudinal direction of the tape form substrate to dissolve the
pulling strength that affects in the longitudinal direction of the
tape form substrate. Because the tape form substrate constituting a
reel-to-reel substrate is successively formed in the longitudinal
direction, the position adjustment is more difficult compared with
the case of single substrate. In the pattern forming system of the
embodiment, the pulling strength that affects in the longitudinal
direction of the tape form substrate is dissolved because a slack
mechanism for the tape form substrate is set up. By moving, in this
state of things, the table that sucks the tape form substrate, the
position adjustment of the tape form substrate can be easily done.
Thus, a pattern forming system that can form a precise pattern can
be provided.
A Droplet Discharge Apparatus
[0051] Next, the above-referenced ink jet head will be specifically
described with reference to FIG. 5. FIGS. 5A and 5B are diagrams
explaining an ink jet head, FIG. 5A being an oblique diagram of a
substantial part while FIG. 5B being a sectional view of a
substantial part. FIG. 6 is a bottom plan view of an ink jet head.
As shown in FIG. 5A, an ink jet head 30 includes a nozzle plate 32
and a diaphragm 33 that are, for example, stainless and are joined
via a compartment item (a reservoir plate) 34. A plurality of
spaces 35 and a liquid receiver 36 are formed with the compartment
items 34 between the nozzle plate 32 and the diaphragm 33. The
inside of each of the spaces 35 and the liquid receiver 36 is
filled with liquid matter, each of the spaces 35 and the liquid
receiver 36 being communicable via a feed pocket 37. On the nozzle
plate 32, a plurality of nozzle holes 38 for spraying liquid matter
from the spaces 35 is formed in line, both lengthwise and
crosswise. A hole 39 is formed on the diaphragm 33 for supplying
liquid matter into the liquid receiver 36.
[0052] As shown in FIG. 5B, a piezo device 40 is jointed on the
surface of the diaphragm 33, on the opposite side of the surface
facing to the space 35. The piezo device 40 is placed between a
pair of electrodes 41 and is configured to stick out outside when
electricity is turned on. The diaphragm 33 to which the piezo
device 40 is jointed in such configuration also sticks out outside
together with the piezo device 40, augmenting the capacity of the
space 35. Thus, liquid matter the amount of which equals to the
augmented capacity in the space 35 flows in from the liquid
receiver 36 via the feed pocket 37. Canceling, in this state of
things, the electricity to the piezo device 40 returns the piezo
device 40 and the diaphragm 33 to the former shape. Thus, the
capacity of the space 35 also returns to the former capacity, which
raises the pressure of the liquid matter within the space 35,
causing a droplet 42 of the liquid matter to be discharged from the
nozzle hole 38 onto a substrate.
[0053] A piezo device 40 is set up separately for each of the
nozzle holes 38 so that a discharging operation is carried out
separately. Specifically, the amount of droplets to be discharged
from each nozzle can be adjusted and changed by controlling
discharge waveforms that are electrical signals to be sent to the
piezo device 40. As a method of the ink jet head 30, it is not
limited to the above-referenced piezo ink jet type using a piezo
device 40. A thermal method, for example, can also be adopted. In
that case, the amount of droplets to be discharged can be changed
by, for example, changing the applying time.
A Wiring Pattern
[0054] Next, an example of a wiring pattern that is formed by using
a droplet discharge method will be described. FIG. 6 is a diagram
explaining an example of a wiring pattern. FIG. 6A is a
two-dimensional sectional view of FIG. 6B on the B-B line, while
FIG. 6B is a lateral sectional view of FIG. 6A on the A-A line. The
pattern shown in FIG. 6B is configured so that a lower layer
electrical wiring 72 and an upper layer electrical wiring 76 are
laminatedly formed via an interlayer insulator film 84 and are
conductively connected to each other through a conductive post 74.
Note that the wiring pattern described below is only an example and
the invention is applicable also for other wiring patterns than the
one in the example.
[0055] The wiring pattern shown in FIG. 6B is formed on the surface
of the above-referenced tape form substrate 11. A base insulator
film 81 is formed on the surface of the tape form substrate 11. The
base insulator film 81 is composed of an electric insulating
material, the main component of which being an ultraviolet ray
hardening resin, such as an acrylic.
[0056] A plurality of electrical wirings 72 is formed on the
surface of the base insulator film 81. The electrical wirings 72
are formed in predetermined patterns with conductive materials,
such as Ag. Meanwhile, an interlayer insulator film 82 is formed,
on the surface of the base insulator film 81, on the area where no
electrical wiring 72 is formed. The line/space of the electrical
wirings 72 is refined, for example, to 30/30 .mu.m by employing a
droplet discharge system.
[0057] An interlayer insulator film 84 is formed in a manner of
mainly covering the electrical wirings 72. The interlayer insulator
film 84 is also composed of the same resin material as that used
for the base insulator film 81. A conductive post 74 with an
appropriate height is formed, upwards from an edge of the
electrical wirings 72, in a manner of piercing the interlayer
insulator film 84. The conductive post 74 is formed with a columnar
structure and composed of the same conductive materials as those
used for the electrical wirings 72, such as Ag. Here, by way of
example, the thickness of the electrical wirings 72 is about 2
.mu.m and the height of the conductive post 74 is about 8
.mu.m.
[0058] An upper layer electrical wiring 76 is formed on the surface
of the interlayer insulator film 84. Like the lower layer
electrical wirings 72, the upper electrical wiring 76 is also
composed of conductive materials, such as Ag. As shown in FIG. 6A,
the upper layer electrical wiring 76 may be placed so as to
intersect with the lower layer electrical wirings 72. The upper
layer electrical wiring 76 is connected to the top of the
conductive post 74 to secure the conduction with the lower layer
electrical wirings 72.
[0059] As shown in FIG. 6B, an interlayer insulator film 86 is
formed on the area, on the surface of the interlayer insulator film
84, where the electrical wiring 76 is not formed. Further, an
overcoat 88 is formed in a manner of mainly covering the electrical
wiring 76. The interlayer insulator film 86 and the overcoat 88 are
also composed of the same resin material as that used for the base
insulator film 81.
[0060] Although the wiring pattern in the above described example
has only two layers of electrical wirings 72 and 76, a wiring
pattern may have electrical wirings with more than two layers. In
such a case, the structure from the n-th layer electrical wiring to
the n+1-th layer electrical wiring may be formed just in the same
way as the structure from the first layer electrical wiring 72 to
the second layer electrical wiring 76 is formed.
A Wiring Pattern Forming Method
[0061] Next, a method for forming the above-referenced wiring
pattern will be described. FIG. 7 is an operation sheet of a wiring
pattern forming method. Now, each operation will be described in
numerical order in the leftmost field of FIG. 7 with reference to
FIG. 6B.
[0062] First, the surface of a tape form substrate 11 is cleaned
(Step 1). Specifically, excimer UV at a wavelength of 172 nm is
irradiated onto the surface of the tape form substrate 11 for about
300 seconds. The tape form substrate 11 may be also cleaned using
solvents, such as water, or ultrasonic waves. It is also acceptable
to clean the tape form substrate 11 by irradiating plasma onto the
tape form substrate 11 at a normal pressure.
[0063] Next, a bank (a peripheral part) for a base insulator film
81 is drawn and formed as a preparatory step to form the base
insulator film 81 on the surface of the tape form substrate 11
(Step 2). The drawing is done using a droplet discharge system (an
inkjet system). Specifically, a resin material before hardened,
which is a forming material of the base insulator film 81, is
discharged along the peripheral part of the area for forming the
base insulator film 81, by using a droplet discharge apparatus to
be described later. Next, the discharged resin material is hardened
(Step 3). Specifically, UV at a wavelength of 365 nm is irradiated
onto the base insulator film 81 for about 4 seconds to harden a UV
hardening resin, which is a forming material of the base insulator
film 81. Thus, a bank is formed on the peripheral part of the area
for forming the base insulator film 81.
[0064] Next, a base insulator film 81 is drawn and formed within
the resulting bank (Step 4). The drawing is also done using a
droplet discharge system. Specifically, a droplet discharge head of
the above-referenced droplet discharge apparatus is scanned
throughout the inside of the bank while a resin material before
hardened, which is a forming material of the base insulator film
81, is discharged from the ink jet head. Here, the discharged resin
material will not spread beyond the area for forming the base
insulator film 81, because the discharged resin material is backed
up at the bank on the peripheral part even in case where the
discharged resin material flows. Next, the discharged resin
material is hardened (Step 5). Specifically, UV at a wavelength of
365 nm is irradiated for about 60 seconds to harden a UV hardening
resin, which is a forming material of the base insulator film 81.
Thus, a base insulator film 81 is formed on the surface of the film
substrate 11.
[0065] Next, the contact angle on the surface of the base insulator
film 81 is adjusted as a preparatory step to form an electrical
wiring 72 on the surface of the base insulator film 81 (Step 6). As
will be described below, in the discharging of a droplet containing
a forming material of an electrical wiring 72, too large contact
angle on the surface of the base insulator film 81 causes the
discharged droplet to become spherical, making it difficult to form
an electrical wiring 72 with a predetermined form and on a
predetermined position. Meanwhile, too small contact angle on the
surface of the base insulator film 81 causes the discharged droplet
to spread out, making it difficult to refine an electrical wiring
72. Because the surface of the base insulator film 81 after
hardened has a liquid repellency, the contact angle on the surface
of the base insulator film 81 can be adjusted by irradiating
excimer UV at a wavelength of 172 nm onto the surface for about 15
seconds. The modification degree of the liquid repellency can be
adjusted not only with the irradiation time of the ultraviolet
light but also with the combinations of intensity and wavelength of
an ultraviolet light and a heat treatment (heating) and the like.
As other methods for lyophilic treatment, there are treatments,
such as a plasma treatment in which oxygen is used as a reaction
gas and a treatment in which a substrate is exposed to ozone
atmosphere.
[0066] Next, a liquid line 72p, which will later become an
electrical wiring, is drawn and formed on the surface of the base
insulator film 81 (Step 7). The drawing is done using a droplet
discharge system that uses a droplet discharge apparatus to be
described later. Here, a dispersion liquid in which conductive
microparticles, which is a forming material of an electrical
wiring, are dispersed in a dispersion medium is discharged. As
conductive microparticles, silver is preferably used. In addition,
metal microparticles that contain any of gold, copper, palladium,
or nickel, and microparticles of conductive polymer or
superconducting properties can be also used.
[0067] As for the conductive microparticles, the surfaces can be
coated, for example, with organic matters for the purpose of
improving the dispersibility. Polymer, which induces steric
hindrance and electrostatic repulsion, for example, is an example
of coating materials to be applied onto the surfaces of conductive
microparticles. Further, it is preferable that the diameter of the
conductive microparticles is in the range of 5 nm to 0.1 .mu.m.
This is because a particle that is greater than 0.1 .mu.m in
diameter easily causes the nozzles to be clogged, making the
discharging from a droplet discharge head difficult. In the
meanwhile, a particle that is smaller than 5 nm in diameter means a
large volume proportion of the coating materials to the conductive
microparticles, causing an excessively large proportion of the
organic matters in the resulting electric conductor.
[0068] Dispersion media to be used are not particularly limited as
long as the above-referenced conductive microparticles can be
dispersed without causing coagulation. In addition to water,
alcohols such as methanol, ethanol, propanol, and butanol,
hydrocarbon compounds such as n-heptane, n-octane, decane, toluene,
xylene, cymene, durene, indene, dipentene, tetrahydronaphthalene,
decahydronaphthalene, and cyclohexylbenzene, ethers compounds such
as ethylene glycol dimethyl ether, ethylene glycol diethyl ether,
ethylene glycol methyl ethyl ether, diethyleneglycol dimethyl
ether, diethylene glycol diethyl ether, diethylene glycol methyl
ethyl ether, 1,2-dimethoxyethane, Bis (2-methoxyethyl)ether, and
p-dioxane, and polar compounds such as propylene carbonate,
gamma-butyrolactone, N-methyl-2-pyrrolidone, dimethylformamide,
dimethyl sulfoxide, and cyclohexanone are acceptable. Among these,
water, alcohols, hydrocarbon compounds, and ethers compounds are
preferable in terms of the dispersibility of particles, the
stability of dispersion liquid, and the applicability to a droplet
discharge system. In particular, water and hydrocarbon compounds
are specifically preferable dispersion media. These dispersion
media can be used as a mixture of more than two kinds of materials
as well as by itself.
[0069] As for dispersion media for a droplet containing conductive
microparticles, it is preferable that its steam pressure at room
temperature is in the range of 0.001 mmHg to 200 mmHg (that is, in
the range of about 0.133 Pa to 26600 Pa). This is because a
dispersion medium, in the case where the steam pressure is higher
than 200 mmHg, evaporates too quickly after the discharging, making
it difficult to form a good electric conductor. Further, the steam
pressure of dispersion media is preferable in the range of 0.001
mmHg to 50 mmHg (that is, in the range of about 0.133 Pa to 6650
Pa). This is because a nozzle, in the case where the steam pressure
is higher than 50 mmHg, is easily clogged due to dryness in the
discharging of droplets using a droplet discharge system, making a
stable discharging difficult. In the meanwhile, in the case where
the steam pressure of a dispersion medium is lower than 0.001 mmHg
at room temperature, the dispersion medium evaporates too slowly
and is inclined to remain in the electric conductor, making it
difficult to get a good electric conductor after a heat treatment
and/or a light treatment, which will be done as post-processes.
[0070] The dispersoid concentration in dispersing the conductive
microparticles into a dispersion medium may be in the range of 1
mass percent to 80 mass percent, and can be adjusted according to a
desired thickness for an electric conductor. When the concentration
surpasses 80 mass percent, the dispersion liquid is prone to
coagulation, which makes it difficult to get a uniform electric
conductor.
[0071] It is preferable that the surface tension of the dispersion
liquid for the conductive microparticles is in the range of 0.02
N/m to 0.07 N/m. This is because when the surface tension is
smaller than 0.02 N/m in discharging a droplet in a droplet
discharge system, the wetting property of the ink composition
toward the nozzle surface increases and induces jet deflection,
while when the surface tension is greater than 0.07 N/m, the form
of the meniscus on the top of the nozzles is unstable and makes it
difficult to control a rate and a timing of discharging. To adjust
a surface tension, a minute amount of surface tension regulants,
such as fluorine-containing compounds, silicon-containing
compounds, and nonion-containing compounds, can be added to the
dispersion liquid within the limits of not lowering unreasonably
the contact angle with the base insulator film 51.
Nonion-containing surface tension regulants improves the wetting
property toward the base insulator film 51 and the levelling of the
film, and is effective in preventing the occurrence of jaggies and
orange peels and the like on the coating film. The dispersion
medium may, if necessary, include organic compounds, such as
alcohol, ether, ester, and ketone.
[0072] It is preferable that the viscosity of the dispersion medium
is in the range of 1 mPas to 50 mPas. This is because when the
viscosity is smaller than 1 mPas in discharging a droplet in a
droplet discharge system, the peripheral part of a nozzle is easily
polluted with the ink flowage, while when the viscosity is greater
than 50 mPas the nozzle aperture is more frequently clogged, making
it difficult to discharge a droplet smoothly.
[0073] According to the embodiment, a droplet (a first droplet) of
the dispersion liquid is discharged from a droplet discharge head
onto a position on which an electrical wiring to be formed. In the
discharging, it is preferable to adjust the overlapping of droplets
to be discharged in succession so as to prevent the occurrence of
bulge. Specifically, it is preferable to use a discharging method
in which a plurality of droplets is discharged, in a first
discharging, at certain intervals so as not to touch each other,
and then the intervals are filled in during the subsequent
discharging. A liquid line 72p is formed on the surface of the base
insulator film 81, following the steps described above.
[0074] Before forming the liquid line 72p on the tape form
substrate 11, the position of the tape form substrate 11 is
adjusted according to Steps 702 to 712 in FIG. 4. Then, after
forming the liquid line 72p, the tape form substrate 11 is fed to
the next step according to Steps 732 to 738 in FIG. 4.
[0075] Next, as shown in FIG. 6B, the liquid line 72p is baked
(Step 8). Specifically, the tape form substrate 11 on which the
liquid line 72p is formed is heated on a hot plate at a temperature
of 150 degrees centigrade for about 30 minutes. Although the baking
is done in the ordinary air, it can also be done, if necessary, in
inert gases atmosphere, such as nitrogen, argon, and helium.
Further, although the temperature of the baking is, here, set to be
150 degrees centigrade, it is preferable to set the temperature
taking into consideration the boiling point (steam pressure) of the
dispersion medium included in the liquid line 72p, the type and the
pressure of the atmosphere gases, thermal behaviors of the
particles, such as dispersibility and oxidativity, the presence and
the amount of a coating material, and a heat resistance of the
substrate.
[0076] The baking process can be done not only by using an ordinary
hot plate or an electric furnace but also by using a lamp anneal.
As a light source to be used for a lamp anneal, although it is not
limited particularly, infrared lamp, xenon lamp, YAG laser, argon
laser, carbon dioxide laser, and excimer laser such as XeF, XeCI,
XeBr, KrF, KrCl, ArF, and ArCl can be used. Although these light
sources are generally used with the output power in the range of 10
W to 5000 W, the range of 100 W to 1000 W is sufficient in the
embodiment.
[0077] After the baking, the dispersion medium contained in the
liquid line 72p is volatilized, securing an electrical connection
between the conductive microparticles. Thus, an electrical wiring
72 is formed.
[0078] Next, a liquid post 74p, which will be a conductive post, is
drawn and formed on an edge of the baked electrical wiring 72 (Step
9). The drawing is done using a droplet discharge system that uses
the above-referenced droplet discharge apparatus, just like the
drawing of a liquid line 72p in Step 7. Here, a droplet (a second
droplet) of the dispersion liquid in which conductive
microparticles, which are a forming material of the liquid post 74,
are dispersed in an dispersion medium is discharged. Specifically,
the droplet is the same as the liquid matter that is used for the
drawing of the liquid line 72p. Specifically, a second droplet can
be discharged, after the liquid line 72p is drawn, onto a forming
position of a conductive post 74 using the same droplet discharge
head in which the same liquid matter is filled.
[0079] It is preferable that the position of the tape form
substrate 11 is adjusted according to Steps 702 to 712 in FIG. 4
before forming the liquid post 74p, just like before forming the
liquid line 72p. Here, the liquid line 72p and the liquid post 74p
can be drawn using the same droplet discharge apparatus. Then,
after forming the liquid post 74p, the tape form substrate 11 is
fed to the next step according to Steps 732 to 738 in FIG. 4.
[0080] Next, as shown in FIG. 6B, the drawn and formed liquid post
74p is baked (Step 10). The baking is done by heating the tape form
substrate 11 on which the liquid post 74p is formed on a hot plate
at a temperature of 150 degrees centigrade for about 30 minutes.
Thus, the dispersion medium contained in the liquid post 74p is
volatilized, securing an electrical connection between the
conductive microparticles. Thus, the liquid post 74p is formed.
[0081] Next, the contact angle on the surface of the base insulator
film 81 is adjusted as a preparatory step to form an interlayer
insulator film 82 on the formative layer of the electrical wiring
72 (Step 11). As the hardened surface of the base insulator film 81
has a liquid repellency, excimer UV at a wavelength of 172 nm is
irradiated onto the surface for about 60 seconds to add a lyophilic
property.
[0082] Next, an interlayer insulator film 82 is drawn and formed
around the electrical wiring 72 (Step 12). The drawing is also done
using the droplet discharge apparatus, just like the drawing of a
base insulator film 81. Here, voids are placed around the
conductive post 74 and around the electrical wiring 72, with the
resin material being discharged outside the voids.
[0083] Next, excimer UV at a wavelength of 172 nm is irradiated
onto the voids around the conductive post 74 and around the
electrical wiring 72 for about 10 seconds as a lyophilic treatment
(Step 13). Thus, a lyophilic property is added to the voids around
the conductive post 74 and around the electrical wiring 72, letting
the resin material flow into the voids and contact with the
conductive post 74 and the electrical wiring 72. Here, the resin
material wetly mounts on the surface of the electrical wiring 72,
but not on the top of the conductive post 74. Therefore, conduction
can be secured between the conductive post 74 and the upper layer
electrical wiring 76. Then, the discharged resin material is
hardened (Step 14). Specifically, UV at a wavelength of 365 nm is
irradiated for about four seconds to harden a UV hardening resin,
which is a forming material of an interlayer insulator film 82.
Thus, an interlayer insulator film 82 is formed.
[0084] Next, an interlayer insulator film 84 is drawn and formed
mainly on the surface of the electrical wiring 72 (Step 15). The
drawing is also done using the droplet discharge apparatus, just
like the drawing of a base insulator film 81. Here again, it is
preferable that a resin material is discharged after a void is
placed around the conductive post 74. Next, the discharged resin
material is hardened (Step 16). Specifically, UV at a wavelength of
365 nm is irradiated for about 60 seconds to harden a UV hardening
resin, which is a forming material of an interlayer insulator film
84. Thus, an interlayer insulator film 84 is formed.
[0085] Next, an upper layer electrical wiring 76 is formed on the
surface of the interlayer insulator film 84. The specific processes
are the same with those in Steps 6 to 10 for forming a lower layer
electrical wiring 72. Then, an interlayer insulator film 86 is
formed on the formative layer of the electrical wiring 76. The
specific processes are the same with those in Steps 11 to 14 for
forming an interlayer insulator film 82 on the formative layer of
the electrical wiring 72. Further, by doing Steps 15 and 16, an
interlayer insulator film can be formed on the surface of the upper
layer electrical wiring 76.
[0086] By repeating the processes in Steps 6 to 16, electrical
wirings can be laminatedly placed. On the surface of the top layer
of the electrical wirings, it is preferable to form an overcoat 88
using the same processes in Steps 15 and 16. In this way, a wiring
pattern of the embodiment shown in FIG. 6 is formed.
[0087] Each of the above-referenced steps is done sequentially
between the feeding reel 10 and the winding reel 15 that are shown
in FIG. 1. Specifically, by staggering the tape form substrate 11
from the droplet discharge apparatus once a pattern is formed on a
unit area using the droplet discharge apparatus, wiring patterns
can be formed very easily also on the other unit areas on the tape
form substrate 11. Thus, according to the embodiment, wiring
patterns can be easily and quickly formed for each of the unit
areas (each substrate area) on the tape form substrate 11
constituting a reel-to-reel substrate, making it possible to
manufacture wiring substrates and the like efficiently and in
volume.
[0088] Further, according to the embodiment, a plurality of steps,
including a droplet discharge step, is carried out from the feeding
out of a tape form substrate 11 constituting a reel-to-reel
substrate from the feeding reel 10 until the winding up of the tape
form substrate with the winding reel 15. Thus, only by winding up
one edge of the tape form substrate 11 with the winding reel 15,
the tape form substrate 11 can be moved from the position on which
the previous step has been carried out to the position on which the
next step is carried out. Thus, according to the embodiment, a
transport mechanism for transferring a tape form substrate 11 to
each apparatus for each step can be simplified, reducing the
installation space for the manufacturing apparatuses, which
eventually reduces the manufacturing cost in the case of volume
production and the like.
An Electro-Optic Device
[0089] Flexible Printed Circuit (hereinafter, simply referred to as
an "FPC") can be formed using the above-referenced wiring pattern
forming method. Thus, a liquid crystal module will now be described
as an example of electro-optic devices that adopt the FPC. FIG. 8
is an exploded oblique diagram of a liquid crystal module with a
COF (Chip On Film) structure. The liquid crystal module 101 mainly
includes a liquid crystal panel 102 for color display, FPC 130 that
is connected to the liquid crystal panel 102, and a liquid crystal
driving IC 100 that is mounted on FPC 130. Further, a lighting
system, such as a backlight, and other accompanying devices are
attached to the liquid crystal panel 102, if necessary.
[0090] The liquid crystal panel 102 includes a pair of substrates
105a and 105b, which are attached to each other with a seal
material 104. A liquid crystal is inserted into a void, so-called
cell gap, between the substrates 105a and 105b. In other words, the
liquid crystal is interposed with the substrates 105a and 105b. The
substrates 105a and 105b are generally composed of translucent
materials, such as glass and synthetic resin. A deflecting plate
106a is attached on the outside surface of the substrates 105a and
105b.
[0091] An electrode 107a is formed on the inside surface of the
substrate 105a while an electrode 107b is formed on the inside
surface of the substrate 105b. The electrodes 107a and 107b are
composed, for example, of translucent materials, such as ITO
(Indium Tin Oxide). The substrate 105a has an overhanging part to
the substrate 105b, a plurality of terminal posts 108 being formed
on the overhanging part. The terminal posts 108 are formed together
with an electrode 107a when the electrode 107a is formed on the
substrate 105a. Therefore, the terminal posts 108 are formed, for
example, with ITO. Among the terminal posts 108, some outlie
directly from the electrode 107a and others are connected to the
electrode 107b via a conductive material (not shown).
[0092] Meanwhile, on the surface of FPC 130, wiring patterns 139a
and 139b are formed by the method for forming a wiring pattern
according to the embodiment. Specifically, an input wiring pattern
139a is formed from one side of FPC 130 toward the center, while an
output wiring pattern 139b is formed from the opposite side of FPC
130 toward the center. Electrode pads (not shown) are formed on the
other sides, which are closer to the center, of the input wiring
pattern 139a and the output wiring pattern 139b.
[0093] A liquid crystal driving IC 100 is mounted on the surface of
FPC 130. Specifically, a plurality of bump electrodes that is
formed on the active surface of the liquid crystal driving IC 100
is connected to the plural electrode pads that are formed on the
surface of FPC 130 via ACF (Anisotropic Conductive Film) 160. The
ACF 160 is formed by dispersing a plurality of conductive particles
into an adhesive resin, which has thermoplasticity or a
thermosetting property. Thus, a so-called COF structure is achieved
by fitting a liquid crystal driving IC 100 on the surface of FPC
130.
[0094] Then, FPC 130 having the liquid crystal driving IC 100 is
connected to the substrate 105a of the liquid crystal panel 102.
Specifically, an output wiring pattern 139b of FPC 130 is connected
electrically to the terminal posts 108 on the substrate 105a via
ACF 140. Here, space saving can be achieved by folding because FPC
130 is flexible.
[0095] In a liquid crystal module 101 configured according to the
method described above, a signal is input into a liquid crystal
driving IC 100 via an input wiring pattern 139a on FPC 130. Then, a
driving signal is output from the liquid crystal driving IC 100 to
the liquid crystal panel 102 via an output wiring pattern 139b on
FPC 130. Thus, an image is displayed on the liquid crystal panel
102.
[0096] In addition to devices that have an electro-optic effect
that changes transmissivity of light by changing the refraction
factor of materials by electric field, devices that transform
electric energy into optical energy are also electro-optic devices
of the invention. Specifically, the invention is widely applicable
not only for liquid crystal display devices but also for
luminescent devices, such as organic EL (Electro-Luminescence)
devices, inorganic EL devices, plasma display devices,
electrophoretic display devices, and display devices using electron
emission elements (such as Field Emission Display and
Surface-Conduction Electron-Emitter Display). For example, FPC
having a wiring pattern according to the invention can be connected
to an organic EL panel to compose an organic EL module.
An Electronic Apparatus
[0097] Next, an electronic apparatus manufactured using a pattern
forming method of the embodiment will be described with reference
to FIG. 9. FIG. 9 is an oblique diagram of a cellular phone. In
FIG. 9, the number 1000 indicates a cellular phone, and the number
1001 indicates a display part. An electro-optic device having a
wiring pattern of the embodiment is adopted to the display part
1001 of the cellular phone 1000. Therefore, a small cellular phone
1000 that has a highly reliable electrical connection can be
provided. The invention can be used as an image displaying method,
not only for the above-referenced cellular phone but also for
electronic apparatuses, such as electronic books, personal
computers, digital still cameras, liquid crystal televisions, video
tape recorders (viewfinder types or monitor types), car navigation
systems, pagers, electronic organizers, desktop calculators, word
processors, workstations, videophones, POS terminals, and touch
panels. In any case, a small electronic apparatus that has a highly
reliable electrical connection can be provided.
[0098] The technology range of the invention is not limited to the
above-referenced embodiments, but may include the embodiments in
which various changes are added to the above-referenced embodiments
within the limits of not deviating from the purposes of the
invention. Specifically, the specific materials and configurations
described above in the embodiments are only the examples and
changes are supposed to be added.
* * * * *