U.S. patent application number 12/402932 was filed with the patent office on 2009-07-09 for liquid droplet discharging method, and liquid droplet discharging apparatus.
This patent application is currently assigned to Seiko Epson Corporation. Invention is credited to Masayuki OKUYAMA.
Application Number | 20090174859 12/402932 |
Document ID | / |
Family ID | 33525946 |
Filed Date | 2009-07-09 |
United States Patent
Application |
20090174859 |
Kind Code |
A1 |
OKUYAMA; Masayuki |
July 9, 2009 |
LIQUID DROPLET DISCHARGING METHOD, AND LIQUID DROPLET DISCHARGING
APPARATUS
Abstract
A liquid droplet discharging method of the present invention
forms a pattern on a substrate by discharging liquid droplets on
the substrate from a discharging bead having a liquid droplet
discharging device, and moving the discharging head and the
substrate relatively, and includes the steps of: preparing CAD data
specified by a combination of a plurality of vector data; preparing
bitmap data including an XY-matrix in which discharging positions
of the liquid droplets are specified based on the CAD data;
preparing liquid droplet discharging data for discharging of the
liquid droplets based on the bitmap data; and forming the pattern
by driving the liquid droplet discharging device based on the
liquid droplet discharging data.
Inventors: |
OKUYAMA; Masayuki; (Suwa,
JP) |
Correspondence
Address: |
HARNESS, DICKEY & PIERCE, P.L.C.
P.O. BOX 828
BLOOMFIELD HILLS
MI
48303
US
|
Assignee: |
Seiko Epson Corporation
Tokyo
JP
|
Family ID: |
33525946 |
Appl. No.: |
12/402932 |
Filed: |
March 12, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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|
11274767 |
Nov 15, 2005 |
7535546 |
|
|
12402932 |
|
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|
10844972 |
May 13, 2004 |
6992746 |
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11274767 |
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Current U.S.
Class: |
349/189 |
Current CPC
Class: |
G02F 1/13415 20210101;
H05K 3/125 20130101; H05K 2203/013 20130101; G02F 1/1303
20130101 |
Class at
Publication: |
349/189 |
International
Class: |
G02F 1/1341 20060101
G02F001/1341 |
Foreign Application Data
Date |
Code |
Application Number |
May 14, 2003 |
JP |
2003-135791 |
Claims
1. A liquid droplet discharging method in which discharging heads
discharge liquid droplets onto a substrate while the discharging
heads and the substrate are relatively moved, thereby foiling a
pattern onto the substrate, the liquid droplet discharging method
comprising the steps of: preparing a CAD data which is specified by
a combination of a plurality of vector data, in accordance with a
configuration of the pattern; preparing a bit map data which
specifies discharging positions of the liquid droplets based on the
CAD data; and preparing a liquid droplet discharging data used for
discharging the liquid droplets based on the bitmap data, wherein
in the step of preparing the liquid droplet discharging data, the
liquid droplet discharging data is prepared in accordance with
impact diameters of the liquid droplets on the substrate.
2. A liquid droplet discharging apparatus in which discharging
heads discharge liquid droplets onto a substrate while the
discharging heads and the substrate are relatively moved, thereby
forming a pattern onto the substrate, the liquid droplet
discharging apparatus comprising: a CAD data preparing device which
prepares a CAD data which is specified by a combination of a
plurality of vector data, in accordance with a configuration of the
pattern; a bitmap data preparing device which prepares a bit map
data which specifies discharging positions of the liquid droplets
based on the CAD data; and a liquid droplet discharging data
preparing device which prepares a liquid droplet discharging data
used for discharging the liquid droplets based on the bitmap data,
wherein the liquid droplet discharging data preparing device
prepares the liquid droplet discharging data in accordance with
impact diameters of the liquid droplets on the substrate.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional application of U.S. Ser.
No. 11/274,767 filed Nov. 15, 2005, which is a continuation
application of U.S. Ser. No. 10/844,972 filed May 13, 2004, now
U.S. Pat. No. 6,992,746 issued Jan. 31, 2006 which claims priority
to Japanese Patent Application No. 2003-135791 filed May 14, 2003.
The entire disclosures of each of the above applications are
incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a liquid droplet
discharging method and to a liquid droplet discharging
apparatus.
[0004] 2. Description of Related Art
[0005] In recent years, liquid crystal devices, electroluminescence
devices and the like have been used for the display unit of
electronic equipment such as mobile telephones and portable
computers. For example, in a liquid crystal device, a color filter
is formed by arranging dot-shaped filter elements of the respective
colors of red, green, and blue in a predetermined pattern such as a
stripe pattern, a delta pattern, or a mosaic pattern on a surface
of a substrate formed from glass, plastic or the like.
[0006] A method of forming this type of color filter is known in
which, while a dye droplet discharging head, which discharges
liquid droplets of red, green, and blue dyes is being scanned,
liquid droplets are discharged onto an acrylic resin that has been
coated onto a glass substrate, so as to adhere thereto (for
example, see Japanese Unexamined Patent Application, First
Publication No. H02-173703).
[0007] Note that, because it is necessary for the respective liquid
droplets to be adhered to positions on the substrate that are
determined in advance, when a large number of color filters are
being formed on a substrate having a large surface area, a
mechanism that can precisely adjust the positions of the substrates
has been required. In particular, in the case of a color filter
that is formed in a minute pattern on a substrate, or in the case
of a circuit having a complex pattern or the like, it is necessary
to provide an adjustment mechanism having a high degree of
precision. Furthermore, if time is needed in order to drive the
mechanism for adjusting the position of a substrate, the tact time
for each single substrate is lengthened.
[0008] The present invention was conceived in view of the above
described drawbacks, and it is an object thereof to provide a
liquid droplet discharging method and a liquid droplet discharging
apparatus that enable an extremely precise pattern to be formed on
a substrate using a simple structure.
SUMMARY OF THE INVENTION
[0009] A liquid droplet discharging method according to the present
invention includes steps of: preparing computer aided design (CAD)
data that is specified by a combination of a plurality of vector
data, in accordance with a configuration of a pattern that is
formed by discharging a liquid droplet from a liquid droplet
discharging device onto a substrate; preparing bitmap data that
specifies discharging positions of the liquid droplet using an XY
matrix based on the CAD data; preparing liquid droplet discharging
data used for discharging the liquid droplet based on the bitmap
data; and forming the pattern by driving the liquid droplet
discharging device in accordance with the liquid droplet
discharging data.
[0010] The "liquid droplet discharging device" has a function of
changing the volume inside the discharging heads in accordance with
a predetermined voltage waveform that is supplied to piezoelectric
elements or the like, and discharging the liquid droplet that has
been pressed in accordance with this. Note that the liquid droplet
discharging device is not limited to an electromechanical converter
that uses a piezoelectric element or the like, and, for example, a
device that uses a thermoelectric converter as an energy generator
may be used, or else continuous methods and electrostatic
absorption methods such as pressure vibration types and
electrification control types may be used.
[0011] The "liquid droplet discharging data" is data that is used
for supplying the voltage waveform to the liquid droplet
discharging device, namely, data used for controlling the discharge
of the liquid droplet by the liquid droplet discharging device.
Data used for moving the discharging head and the substrate
relatively to each other is contained in this liquid droplet
discharging data, namely, the liquid droplet discharging data is
also used for determining the discharging position of the liquid
droplets on the substrate. The data format of this liquid droplet
discharging data is a time series data format formed using "0" and
"1", and is stored in read only memory (ROM) or random access
memory (RAM).
[0012] The "pattern" is formed by discharging a material that is
capable of being discharged in droplet form onto predetermined
positions on a substrate. The term "pattern" refers to pixel
patterns of RGB color filters formed by red (R), green (G), and
blue (B), circuit patterns having, for example, resistance,
capacitance formed by a capacitative element such as a condenser,
and inductance such as antennas and coils having a labyrinth
structure, patterns having switching elements such as thin film
transistors (TFT) having semiconductors and pixel electrodes that
are connected to the switching elements and the like, and oriented
film materials and liquid crystal materials that require localized
discharges and the like. The term "switching element" refers to
elements that are formed using a material that is capable of being
discharged as a liquid droplet.
[0013] The "substrate" is the object of the liquid droplet
discharge on which a pattern is formed by discharging the above
described liquid droplet. A variety of materials may be used for
the substrate. For example, if transparency is required a substrate
such as glass or the like may be used, while if transparency is not
required a metal substrate or the like may be used. There are no
particular restrictions on the size of the substrate and, in the
present invention in particular, the term "substrate" refers to a
large size substrate in excess of one meter.
[0014] According to the present invention, by using a computer
provided with a display section such as a monitor and an input
section such as a keyboard, it is possible to prepare in advance as
CAD data a pattern formed by the above described discharge of a
liquid droplet.
[0015] Moreover, it is possible to prepare bitmap data by
converting the CAD data that has been prepared in this way.
[0016] After the liquid droplet discharging data has been prepared
based on this bitmap data, by then making a discharge from a
discharging head onto a predetermined position on the substrate
based on the liquid droplet discharging data, it is possible to
form a pattern on the substrate.
[0017] It is possible that: the pattern is formed by laminating a
plurality of functional layers each having predetermined functions;
the CAD data has a plurality of layer data that correspond to the
functional layers; the bitmap data are prepared based on the
plurality of layer data; the plurality of liquid droplet
discharging data is prepared based on the plurality of bitmap data;
and the pattern, which is formed by the plurality of functional
layers, is formed by driving the liquid droplet discharging
apparatus in accordance with the plurality of liquid droplet
discharging data.
[0018] The term "functional layers" refers to each of the layers
that make up the pattern, and refers, for example, to each layer of
the aforementioned inductance, capacitance, resistance, switching
elements, and the like. Namely, the above described pattern is
formed by laminating each of these functional layers.
[0019] The "layer data" is prepared in advance on a computer or the
like that is used for forming the aforementioned functional
layers.
[0020] When the above described method is used, it is possible to
prepare a plurality of bitmap data based on a plurality of layer
data. In addition, it is possible to prepare a plurality of liquid
droplet discharging data based on this plurality of bitmap data.
Furthermore, by discharging liquid droplet based on this plurality
of liquid droplet discharging data, it is possible to form a
plurality of functional layers. Accordingly, it is possible to form
a pattern in which a plurality of functional layers have been
laminated.
[0021] It is possible that: a discharging head group that is formed
by a plurality of the discharging heads is provided; and the
pattern is formed by making the discharging heads of the
discharging head group discharge the liquid droplet independently
for each of the plurality of functional layers.
[0022] Here, a description is given of when the discharging head
group has, for example, a first discharging head that discharges
liquid droplet containing a metal material, a second discharging
head that discharges liquid droplet containing an insulating film
material, and a third discharging head that discharges liquid
droplet containing a transparent electrode material. Firstly, when
forming a functional layer that is made up of metal wiring on a
substrate, bitmap data is prepared from layer data that is used for
forming the metal wiring. Next, liquid droplet discharging data is
prepared, and the first discharging head discharges liquid droplet
containing a metal material based on this liquid droplet
discharging data. Next, when forming the functional layers of the
insulating film and transparent electrode, in the same way as is
described above, groups of liquid droplet discharging data are
prepared from layer data that is used for forming the insulating
film and the transparent electrode. Based on these groups of data,
the second discharging head then discharges liquid droplet
containing insulating film material, and the third discharging head
discharges liquid droplet containing transparent electrode
material.
[0023] When the discharging head group is provided with the first,
the second, and the third discharging head, and separate discharges
of liquid droplet are made using these discharging beads, it is
possible to form a pattern that is made up of a plurality of
functional layers.
[0024] It is possible that: a plurality of liquid droplet
discharging units each including the discharging heads that form
the functional layers on the substrate by discharging the liquid
droplet onto the substrate; and the pattern that is formed by the
plurality of functional layers, is formed by making each of the
plurality of liquid droplet discharging units discharge the liquid
droplet independently for each of the plurality of functional
layers.
[0025] Here, a description is given of when a pattern is formed
using, for example, a first liquid droplet discharging unit that
discharges liquid droplet containing a metal material, a second
liquid droplet discharging unit that discharges liquid droplet
containing an insulating film material, and a third liquid droplet
discharging unit that discharges liquid droplet containing a
transparent electrode material. Firstly, when forming a functional
layer that is made up of metal wiring on a substrate, bitmap data
is prepared from layer data that is used for forming the metal
wiring. Next, liquid droplet discharging data is prepared, and
liquid droplet containing a metal material is discharged onto the
substrate by the first liquid droplet discharging unit based on
this liquid droplet discharging data. Next, when forming the
functional layers of the insulating film and transparent electrode,
in the same way as is described above, groups of liquid droplet
discharging data are prepared from layer data that is used for
forming the insulating film and the transparent electrode. Based on
these groups of data, liquid droplet containing insulating film
material is then discharged by the second liquid droplet
discharging unit, and liquid droplet containing transparent
electrode material is discharged by the third liquid droplet
discharging unit. It is preferable that a transporting unit for
transporting a substrate is placed between each of the first,
second, and third liquid droplet discharging units.
[0026] In this way, when separate discharges of liquid droplet are
made using the first, second, and third liquid droplet discharging
units, it is possible to form a pattern that is made up of a
plurality of functional layers.
[0027] It is possible that: the layer data includes film thickness
data that specifies film thicknesses of the functional layers; and
a number of discharges of the liquid droplet that is discharged
from the discharging heads and a discharging quantity of the liquid
droplet are set based on the film thickness data.
[0028] The term "film thickness data" refers to the film thickness
of the material that constitutes the functional layers. For
example, when forming metal wiring or the like, a method is
employed in which a liquid that has been obtained by dispersing
fine metal particles in a volatile solvent is discharged as liquid
droplets. In this method, the number of discharges and the
discharge quantities of the liquid droplet can be set after the
content of the fine metal particles has been adjusted, and after
changes in the nature and changes in the volume of the material
that are caused by the drying processing and heat processing that
are performed in order to precipitate out the fine metal particles
have been adjusted.
[0029] If the above described method is employed, then it is
possible to set the number of discharges of the liquid droplet and
the discharge quantities of the liquid droplet by adjusting the
content of material and the like contained in the liquid droplet
that is further discharged based on the film thickness data.
[0030] A liquid droplet discharging apparatus of the present
invention includes a computer aided design (CAD) data preparing
device that prepares CAD data, which is specified by a combination
of a plurality of vector data groups, in accordance with a
configuration of a pattern that is formed by discharging a liquid
droplet from a liquid droplet discharging device onto a substrate;
and a preparing device that prepares bitmap data that specifies
discharging positions of the liquid droplet using an XY matrix
based on the CAD data; wherein the pattern is formed by driving the
liquid droplet discharging device in accordance with the liquid
droplet discharging data.
[0031] According to the present invention, it is possible to
prepare in advance as CAD data a pattern that is formed by the
discharge of liquid droplet using a CAD data preparing device. In
addition, bitmap data can be prepared using a bitmap data preparing
device. It is also possible to prepare liquid droplet discharging
data based on this bitmap data using a preparing device.
Furthermore, by discharging liquid droplet onto predetermined
positions on a substrate from a discharging head based on this
liquid droplet discharging data, it is possible to form a pattern
on the substrate.
[0032] It is possible that: the pattern is formed by laminating a
plurality of functional layers each having predetermined functions;
the CAD data preparing device prepares a plurality of layer data
that correspond to the plurality of functional layers; the bitmap
data preparing device prepares the plurality of bitmap data based
on the plurality of layer data; the preparing device prepares the
plurality of liquid droplet discharging data based on the plurality
of bitmap data; and the pattern, which is formed by the plurality
of functional layers, is formed by driving the liquid droplet
discharging device in accordance with the plurality of liquid
droplet discharging data.
[0033] In this case, it is possible for the CAD data preparing
device to prepare a plurality of layer data. It is also possible
for the bitmap data preparing device to prepare a plurality of
bitmap data based on the plurality of layer data. Furthermore, it
is possible for the preparing device to prepare a plurality of
liquid droplet discharging data based on the plurality of bitmap
data. A plurality of functional layers can then be formed by
discharging liquid droplet based on the plurality of liquid droplet
discharging data. Accordingly, it is possible to form a pattern in
which a plurality of functional layers are laminated.
[0034] It is possible that: a discharging head group formed by the
plurality of discharging heads is provided; and the discharging
head group discharges the liquid droplet independently for each of
the plurality of functional layers.
[0035] Here, a description is given of when the discharging head
group has, for example, a first discharging head that discharges
liquid droplet containing a metal material, a second discharging
head that discharges liquid droplet containing an insulating film
material, and a third discharging head that discharges liquid
droplet containing a transparent electrode material. Firstly, when
forming a functional layer that is made up of metal wiring on a
substrate, bitmap data is prepared from layer data that is used for
forming the metal wiring. Next, liquid droplet discharging data is
prepared, and the first discharging head discharges liquid droplet
containing a metal material based on this liquid droplet
discharging data. Next, when forming the functional layers of the
insulating film and transparent electrode, in the same way as is
described above, groups of liquid droplet discharging data are
prepared from layer data that is used for forming the insulating
film and the transparent electrode. Based on these groups of data,
the second discharging head then discharges liquid droplet
containing insulating film material, and the third discharging head
discharges liquid droplet containing transparent electrode
material.
[0036] In this manner, when the discharging head group is provided
with the first, the second, and the third discharging head, and
separate discharges of liquid droplet are made using these
discharging heads, it is possible to form a pattern that is made up
of a plurality of functional layers.
[0037] It is possible that: a plurality of liquid droplet
discharging units each having the discharging heads is provided;
and each of the plurality of liquid droplet discharging units
discharges the liquid droplet independently for each of the
plurality of functional layers.
[0038] A description is given of when a pattern is formed using,
for example, a first liquid droplet discharging unit that
discharges liquid droplet containing a metal material, a second
liquid droplet discharging unit that discharges liquid droplet
containing an insulating film material, and a third liquid droplet
discharging unit that discharges liquid droplet containing a
transparent electrode material. Firstly, when forming a functional
layer that is made up of metal wiring on a substrate, bitmap data
is prepared from layer data that is used for forming the metal
wiring. Next, liquid droplet discharging data is prepared, and
liquid droplet containing a metal material is discharged onto the
substrate by the first liquid droplet discharging unit based on
this liquid droplet discharging data. Next, when forming the
functional layers of the insulating film and transparent electrode,
in the same way as is described above, groups of liquid droplet
discharging data are prepared from layer data that is used for
forming the insulating film and the transparent electrode. Based on
these groups of data, liquid droplet containing insulating film
material is then discharged by the second liquid droplet
discharging unit, and liquid droplet containing transparent
electrode material is discharged by the third liquid droplet
discharging unit. It is preferable that a transporting unit for
transporting a substrate is placed between each of the first,
second, and third liquid droplet discharging units.
[0039] In this way, when separate discharges of liquid droplet are
made using the first, second, and third liquid droplet discharging
units, it is possible to form a pattern that is made up of a
plurality of functional layers.
[0040] It is possible that: the layer data includes film thickness
data that specifies film thicknesses of the functional layers; and
the CAD data preparing device includes a setting device that sets a
number of discharges of the liquid droplet that is discharged from
the discharging heads and a discharging quantity of the liquid
droplet based on the film thickness data.
[0041] The "setting device" sets the number of discharges and the
discharge quantity of liquid droplet after the proportions of the
materials for the functional layers that are contained in the
liquid droplet have been adjusted and after changes in the nature
and changes in the volume of the material that are caused by
processing such as the drying processing and the like have been
adjusted. For example, when forming metal wiring or the like, a
method is employed in which a liquid that has been obtained by
dispersing fine metal particles in a volatile solvent is discharged
as liquid droplets. In this method, the number of discharges and
the discharge quantities of the liquid droplet can be set after the
content of the fine metal particles has been adjusted, and after
changes in the nature and changes in the volume of the material
that are caused by the drying processing and heat processing that
are performed in order to precipitate out the fine metal particles
have been adjusted.
[0042] If the above described method is employed, then it is
possible to set the number of discharges of the liquid droplet and
the discharge quantities of the liquid droplet by adjusting the
content of material and the like contained in the liquid droplet
that is further discharged based on the film thickness data.
BRIEF DESCRIPTION OF THE DRAWINGS
[0043] FIG. 1 is a perspective view showing the structure of the
liquid droplet discharging apparatus of the present invention.
[0044] FIG. 2 is a block diagram describing functions of a control
unit of the liquid droplet discharging apparatus of the present
invention.
[0045] FIG. 3 is a flow chart for forming pixels using the liquid
droplet discharging apparatus of the present invention.
[0046] FIG. 4 is a flow chart that continues on from the flow chart
shown in FIG. 3.
[0047] FIGS. 5A to 5C are perspective views showing a circuit
pattern formed using the liquid droplet discharging method of the
present invention.
[0048] FIG. 6 is a structural view showing the structure of the
liquid droplet discharging apparatus of the present invention.
[0049] FIGS. 7A and 7B are a views showing a liquid crystal display
device formed using the liquid droplet discharging method of the
present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0050] FIG. 1 is a perspective view showing the structure of the
liquid droplet discharging apparatus according to an embodiment of
the present invention.
[0051] As is shown in FIG. 1, the liquid droplet discharging
apparatus 1 is provided with a control unit 2, a discharging head
group 3, and a stage 4 as the main structural elements thereof.
[0052] In this type of liquid droplet discharging apparatus 1, as a
result of the control unit 2 controlling operations of the
discharging bead group 3 and the stage 4, liquid droplets are
discharged onto a substrate 5 that has been placed on the stage 4
so that a predetermined pattern is formed on the substrate 5.
[0053] Next, a description of the respective component elements
will be given.
[0054] In the description given below, a direction of orientation
of the discharging bead group 3 is taken as the X direction, a
direction in which the substrate 5 is transported is the Y
direction, and an in-plane direction of rotation within the XY
plane is taken as the .theta. direction.
[0055] The discharging head group 3 is formed by a plurality of
discharging heads 3a that are arranged in a single row, and is
provided so as to be able to move along an X direction shaft 8 that
is constructed so as to extend in the X direction over the stage 4
between supporting columns 7 and 7 that stand vertically upright
from a base 6. A large number of nozzles (for example, 180 nozzles
may be formed in one row) that discharge liquid droplets are formed
facing the substrate 5 in each discharging head 3a forming the
discharging head group 3.
[0056] The discharging heads 3a are constructed so as to have a
cavity that holds liquid droplets, nozzles that are connected to
this cavity, and a liquid droplet discharging device that
discharges liquid droplet held in the cavity from the nozzles in
the form of liquid droplets. The liquid droplet discharging devices
are formed by piezoelectric elements (i.e., piezo elements), and
are provided in a wall surface of the discharging heads 3a. In a
discharging head 3a that has been formed in this manner, as a
result of a desired voltage waveform being supplied to the
piezoelectric element, the wall surface of the discharging head 3a
is deformed so that the volume inside the cavity changes and a
predetermined quantity of liquid droplets are discharged from the
nozzles. The voltage waveform that is supplied to the piezoelectric
element is prepared on the basis of liquid droplet discharging data
(described below).
[0057] The liquid droplet discharge device of the discharging heads
3a may be a device other than the aforementioned electromechanical
converter that uses a piezoelectric element. For example, methods
that may be employed include a method that uses a thermoelectric
converter as an energy generator, an electrification control type
or pressure vibration type of continuous method, an electrostatic
absorption method, or a method in which heat is generated by the
irradiation of an electromagnetic wave such as a laser, and liquid
droplet is discharged by an action resulting from this heat
generation.
[0058] Liquid droplet tanks that store a material liquid are
connected to each of the plurality of discharging heads 3a via a
flow passage of a pump or the like. By storing different types of
material liquid in the respective liquid droplet tanks, it becomes
possible to form different material liquids on a substrate from the
respective discharging heads 3a. Namely, as a result of the
selective use of each of the plurality of discharging heads 3a in
the discharging head group 3, it becomes possible to discharge
predetermined material liquids onto the substrate 5.
[0059] The above described discharging head group 3 is formed by a
plurality of discharging heads 3a that are arranged in one row,
however, the discharging head group 3 is not limited to this. For
example, it is also possible to arrange two rows of discharging
heads 3a that are staggered in the X direction by half a pitch
relative to the spacing between (i.e., the pitch of) nozzles of
each discharging head 3a. If a large number of rows of discharging
heads 3a are provided, liquid droplets can be discharged at a
spacing that is less than the spacing between nozzles.
[0060] It is also possible for the discharging heads 3a to be
inclined at a predetermined angle relative to the X direction. In
this case as well, liquid droplets can be discharged at a spacing
that is less than the spacing between nozzles.
[0061] The stage 4 is formed by a placement portion 4a that is
provided with pins or the like (not shown) on which the substrate 5
is placed and precisely positioned, a base portion 4b that is
connected so as to be able to rotate the placement portion 4a
within the XY planes. An encoder 4c is provided on the base portion
4b. The encoder 4c reads a scale of a linear scale 15 that is
provided extending in the Y direction of the base 6, thereby
enabling the position of the stage 4 in the Y direction to be
detected.
[0062] The stage 4 is constructed so as to be able to move along a
Y direction shaft 9 that is provided so as to be orthogonal to the
X direction. An example of a transporting mechanism to move the
stage 4 in the Y direction is a linear motor that is formed by a
permanent magnet 10 that is located above the Y direction shaft 9
and a plurality of coils (not shown) that extend in the Y direction
on a plate 11 that is fixed to the bottom side of the base portion
4b of the stage 4 and that are also placed adjacent to the
permanent magnet 10.
[0063] The substrate 5 is the subject on which a pattern is formed
in the present embodiment. The material of the substrate 5 may be a
transparent substrate such as glass, however, if transparency is
not required, metal plate or the like may be used. Both the length
and width of the substrate 5 exceed 1 m in size.
[0064] Examples of the pattern that is formed on the substrate 5
include a pixel pattern formed by color filters having RGB colors,
and metal wiring and the like when a TFT circuit is being
formed.
[0065] The control unit 2 is connected electrically to each
component element of the above described liquid droplet discharging
apparatus 1, and may be what is commonly known as a computer to
which a central processing unit (CPU), ROM, RAM, input and output
interfaces, oscillation circuits and the like are connected via a
bus. A control unit 2 such as this performs the integrated control
of the liquid droplet discharging apparatus 1 in accordance with a
program that has been input in advance.
[0066] Next, the structure of the control unit 2 will be described
in detail with reference made to FIG. 2.
[0067] FIG. 2 is a block diagram describing the functions of the
control unit 2.
[0068] As is shown in FIG. 2, the control unit 2 has a liquid
droplet discharging data setting value input section 20, a
discharging head setting value input section 22, a CAD data
operations section (i.e., a CAD data preparing device) 24, a bitmap
data preparing section (i.e., a bitmap data preparing device) 26, a
bitmap processing section 28, a liquid droplet discharging data
preparing section (i.e., preparing device) 30, a liquid droplet
discharging data transfer section 32, a switch group 34, a head
driving section 38, a head drive control section 40, a head
position detecting section 42, and a liquid droplet discharge
timing control section 44.
[0069] The liquid droplet discharging data setting value input
section 20 has the functions of setting the dimensions of the
substrate 5, setting the dimensions of chips in order for the
substrate 5 to be cut into a plurality of chips, setting the pitch
between adjacent chips, setting pixel layout (i.e., pattern),
setting the number of pixels, setting pixel dimensions (i.e. the
horizontal and vertical sizes of the pixels), and setting the pitch
between adjacent pixels.
[0070] The discharging head setting value input section 22 has the
functions of setting the quantity of liquid droplets required to
form the pixels, setting the number of passes of the substrate 5
and discharging head group 3 required to form the pixels, setting
the number of the aforementioned discharging heads 3a of the
discharging head group 3 to be used, and setting the placement of
the discharging heads 3a.
[0071] The CAD data operations section 24 has the function of
creating CAD data that forms the design drawing of the pattern to
be formed on the substrate, and is formed by an input device used
for inputting drawing information (i.e., vector data and data on
the attributes of the drawings and the like), and a workstation or
the like having a drawing processing function. The CAD data
operations section 24 has a layer preparing section 24a and a layer
thickness setting section (i.e. setting device) 24b.
[0072] When the pattern is a laminated structure that is formed by
laminating a plurality of layers (i.e., functional layers), the
layer preparing section 24a has the function of preparing layer
data for each layer as a portion of the CAD data. The layer
thickness setting section (i.e., setting device) 24b sets the film
thickness of these layers, and also has the function of setting the
discharge quantity of liquid droplets and the number of discharges
of liquid droplets that are discharged from the discharging heads
3a.
[0073] The bitmap data preparing section 26 has the function of
preparing bitmap data in accordance with each layer based on the
CAD data having the aforementioned layers.
[0074] The bitmap processing section 28 performs processing to
alter the bitmap data prepared by the bitmap data preparing section
26 in accordance with the number and placement of the discharging
heads or with the need to narrow the line width of the circuit
pattern in consideration of the impact diameter of the liquid
droplets on the substrate.
[0075] The liquid droplet discharging data preparing section 30
prepares droplet discharging data (i.e., binary time series data)
in consideration of the impact diameter when the liquid droplets
impact on the substrate so that a predetermined pattern size is
obtained. This liquid droplet discharging data includes recorded
data of the number of dots that corresponds to the number of the
respective liquid droplet discharge devices that are provided to
correspond to the number of respective liquid droplet discharge
devices that are provided to correspond to the respective nozzles
of the discharging head group 3.
[0076] The liquid droplet data transfer section 32 has the function
of transferring liquid droplet discharging data output from the
liquid droplet discharging data preparing section 30 to the liquid
droplet discharge devices of the discharging head group 3.
[0077] The switch group 34 is provided between the liquid droplet
discharging data transfer section 32 and the discharging head group
3, and is formed by a plurality of switches that are connected
one-on-one to each of the plurality of drive sections included in
the discharging head group 3, and that are set in an ON or OFF
state by the recorded data transferred from the liquid droplet
discharging data transfer section 32.
[0078] The head driving section 38 is integrated with the
discharging head group 3. The head driving section 38 may, for
example, be a linear motor, and moves the discharging head group 3
in an orthogonal direction relative to the transporting direction
of the substrate 5.
[0079] The head drive control section 40 performs drive control of
the head driving section 38 based on instructions from a system
host controller (not shown).
[0080] The head position detecting section 42 has the function of
detecting the amount of displacement of the position of the stage 4
to which the substrate 5 is fixed, namely, of detecting the
relative position of the discharging head group 3 above the
substrate 5. This head position detecting section equates to the
aforementioned encoder 4c.
[0081] The liquid droplet discharge timing control section 44
supplies drive signals to each of the plurality of drive sections
at timings that are based on detection outputs from the head
position detecting section 42.
[0082] Next, the operation of the liquid droplet discharging
apparatus (i.e., the liquid droplet discharging method) according
to the present embodiment will be described with reference made to
FIG. 3, FIG. 4, and FIGS. 5A to 5C.
[0083] FIG. 3 and FIG. 4 are flowcharts showing the formation of a
circuit pattern on the substrate 5. FIGS. 5A to 5C are perspective
views showing a circuit pattern formed in the present embodiment.
FIGS. 5A to 5C are views showing the process by which a circuit
pattern is formed.
[0084] As is shown in FIG. 5C, a circuit pattern (i.e., a pattern)
P is formed by conductive wires (i.e., functional layers) P1 and
P3, and by an insulating film (i.e., a functional layer) P2. A
material liquid containing fine metal particles or the like is used
for the formation of the conductive wires P1 and P3, while a
material liquid containing an organic insulating material or the
like is used for the formation of the insulating film P2.
Discharging heads 3a that discharge each of these material liquids
are placed in the discharging head group 3.
[0085] Next, the liquid droplet discharging method in which a
circuit pattern P is formed on the substrate 5 will be described
based on the flowcharts shown in FIG. 3 and FIG. 4.
[0086] Firstly, the size of the substrate onto which liquid
droplets are to be discharged and the liquid droplet discharge
resolution are determined (step 100).
[0087] Next, CAD data of the circuit pattern P is output to the
bitmap data preparing section 26 by the CAD data operations section
24 (step 101).
[0088] Step 101 will now be described in detail.
[0089] Firstly, each layer (i.e., P1, P2, and P3) constituting the
circuit pattern P is prepared as a layer of CAD data by the layer
preparing section 24a. In addition, the film thickness of this
layer is set by the layer thickness setting section 24b. By setting
the film thickness of the layer the discharge quantity of the
liquid droplets and the number of discharges of liquid droplets
that are discharged from the discharging head 3a is automatically
set.
[0090] Next, the bitmap data preparing section 26 prepares
respective bitmap data based on each layer of the CAD data, and
outputs it to the liquid droplet discharging data preparing section
30 (step 102).
[0091] Next, the bitmap data processing section 28 processes the
aforementioned bitmap data in accordance with the specifications of
the liquid droplet discharge (step 103). Namely, in consideration
of cases in which the nozzle pitch of the discharging head group 3
does not match the pixel pitch, or in which the required quantity
of liquid droplets cannot be supplied in a single discharge, or in
which if they are supplied in a single discharge the liquid
droplets harden and the target pattern cannot be obtained,
processing to alter the bitmap data is performed.
[0092] Next, the number and placement of the discharging heads of
the discharging head group 3 to be used is decided and is input
into the liquid droplet discharging data preparing section by the
discharging head setting value input section 22 (step 104).
[0093] Next, in the liquid droplet discharging data preparing
section 30, liquid droplet discharging data is prepared for each
layer (i.e., P1, P2, and P3) of the circuit pattern P (step 105)
based on the data input by the bitmap data processing section 28
and the discharging head setting value input section 22.
[0094] Next, the substrate 5 is transported by the transporting
mechanism of the stage 4 and the head drive control section 40, and
is precisely positioned (step 106).
[0095] Next, all the liquid droplet discharging data is transferred
to the liquid droplet discharging data transfer section 32 (step
107).
[0096] In the liquid droplet discharging data transfer section 32,
firstly, when forming the conductive wire P1, the liquid droplet
discharging data from the first pass is transferred to the
discharging head group 3 via the switch group 34 (step 108). Next,
liquid droplets are discharged by the discharging head group 3 onto
the substrate 5 that has been transported to a position facing the
nozzles of the discharging head group 3 (step 109).
[0097] Next, a determination is made as to whether or not the
liquid droplet discharge has ended for the first pass (step 110).
If the determination in step 110 is negative, the routine moves
back to step 109, and the above described processing is repeated.
If, however, the determination in step 110 is positive, liquid
droplet discharging data from the next pass is transferred to the
discharging head group 3 via the switch group 34 (step 111). Next,
liquid droplets are discharged by the discharging head group 3 onto
the substrate 5, as is described above (step 112).
[0098] Next, a determination is made as to whether or not liquid
droplet discharges have ended for all passes (step 113). If the
determination in step 113 is negative, the routine moves back to
step 111 and the above described processing is repeated. If,
however, the determination in step 113 is positive, the conductive
wire P1 is formed in the manner shown in FIG. 5A. Subsequently, a
determination is made as to whether or not all the layers (i.e.,
P1, P2, and P3) of the circuit pattern P have been formed (step
114). If the determination in step 114 is negative, namely, if the
insulating film P2 and the conductive wire P3 have not been formed,
the routine moves back to step 108 and, by repeating the above
described processing, the insulating film P2 and the conductive
wire P3 are formed in the manner shown in FIG. 5B and FIG. 5C.
[0099] If the determination in step 114 is positive, namely, if all
the layers (i.e., P1, P2, and P3) of the circuit pattern P have
been formed, the substrate 5 is transported out so that it can be
forwarded to other steps by the transporting mechanism of the stage
4 (step 115).
[0100] As is described above, when forming the circuit pattern P by
the discharge of liquid droplets, it is possible to prepare the
circuit pattern as CAD data. Moreover, by converting the prepared
CAD data, bitmap data can be prepared. Furthermore, after creating
liquid droplet discharging data based on this bitmap data, by
making a discharge from the discharging heads onto a predetermined
position on a substrate based on this liquid droplet discharging
data, it is possible to form the circuit pattern P on the substrate
5.
[0101] In addition, it is possible to prepare a plurality of bitmap
data based on the layers that constitute the CAD data. It is also
possible to prepare a plurality of liquid droplet discharging data
based on the plurality of bitmap data. Furthermore, by discharging
liquid droplets based on this plurality of liquid droplet
discharging data, it is possible to form a plurality of layers
(i.e., P1, P2, and P3).
[0102] Moreover, as a result of the discharging bead group 3 using
discharging beads 3a for each different type of material liquid,
and separately discharging this plurality of material liquids, it
is possible to form a circuit pattern P made up of a plurality of
layers (i.e., P1, P2, and P3).
[0103] Furthermore, it is possible to adjust the material content
contained in liquid droplets subsequently discharged, and set the
number of discharges of the liquid droplets as well as the
discharge quantity of the liquid droplets based on the film
thickness of the layers.
[0104] Next, another embodiment of the liquid droplet discharging
apparatus of the present invention will be described.
[0105] FIG. 6 is a structural view showing the structure of a
liquid droplet discharging apparatus.
[0106] In the present embodiment, a description of previously
described structures and operations is omitted, and only those
portions that differ from those of the above described embodiment
are described.
[0107] As is shown in FIG. 6, a liquid droplet discharging
apparatus 81 is provided with a first liquid droplet discharging
section (i.e., liquid droplet discharging unit) U1, a second liquid
droplet discharging section (i.e., liquid droplet discharging unit)
U2, a third liquid droplet discharging section (i.e., liquid
droplet discharging unit) U3, a substrate transporting section U4,
a substrate delivery section U5, and a substrate removal section
U6.
[0108] Each of the first liquid droplet discharging section U1, the
second liquid droplet discharging section U2, and the third liquid
droplet discharging section U3 is provided with a discharging head
3a for discharging a single type of material liquid in droplet
form, a stage 4 for moving the discharging head 3a relatively to
the substrate 5, and a control unit 2 for controlling the
operations of each of these. The first and third liquid droplet
discharge sections U1 and U3 respectively discharge droplets of
different material liquids that contain fine metal particles for
forming the conductive wires P1 and P3. The second liquid droplet
discharge section U2 discharges droplets of a material liquid that
contains an organic insulating material or the like for forming the
insulating film P2. Accordingly, as a result of each of the liquid
droplet discharging sections U1, U2, and U3 discharging liquid
droplets, the conductive wires P1 and P3 and the insulating film P2
are formed, and ultimately the circuit pattern P is formed on the
substrate 5.
[0109] The substrate transporting section U4 transports a substrate
5 delivered from the substrate delivery section U5 to each of the
liquid droplet discharge sections U1, U2, and U3, and ultimately
removes the substrate 5 on which the circuit pattern P has been
formed from the substrate removal section U6.
[0110] A liquid droplet discharging method that uses the liquid
droplet discharging apparatus 81 will now be described.
[0111] Firstly, the substrate transporting section U4 transports a
substrate 5 from the substrate delivery section U5 to the first
liquid droplet discharging section U1. In this first liquid droplet
discharging section U1, by discharging a material liquid containing
fine metal particles using the liquid droplet discharging method
described above, the conductive wire P1 shown in FIG. 5A is
formed.
[0112] Next, the substrate transporting section U4 transports the
substrate 5 from the first liquid droplet discharging section U1 to
the second liquid droplet discharging section U2. In the second
liquid droplet discharging section U2, by discharging a material
liquid containing an organic insulating material using the liquid
droplet discharging method described above, the insulating film P2
shown in FIG. 5B is formed.
[0113] Next, the substrate transporting section U4 transports the
substrate 5 from the second liquid droplet discharging section U2
to the third liquid droplet discharging section U3. In the third
liquid droplet discharging section U3, by discharging a material
liquid containing fine metal particles using the liquid droplet
discharging method described above, the insulating film P3 shown in
FIG. 5C is formed.
[0114] Next, the substrate transporting section U4 transports the
substrate 5 from the third liquid droplet discharging section U3 to
the substrate removal section U6.
[0115] As is described above, by performing separate droplet
discharges using the respective liquid droplet discharging sections
U1, U2, and U3, it is possible to form a circuit pattern P made up
of a plurality of layers (i.e., P1, P2, and P3).
[0116] Next, a process to manufacture a liquid crystal display
device using the liquid droplet discharging method of the present
invention will be described in detail.
[0117] FIGS. 7A and 7B are views describing a liquid crystal
display device. FIG. 7A shows equivalent circuits of various types
of elements and wiring and the like such as switching elements that
constitute an image display area of a liquid crystal display
device. FIG. 7B shows principal portions of a liquid crystal
display device, and is a perspective view for describing the
structure of pixel electrodes and switching elements provided in
each pixel.
[0118] In the description given below, a description of previously
described structure and operations is omitted, and only those
portions that are different are described.
[0119] Firstly, a liquid crystal display device formed using the
liquid droplet discharging method of the present invention will be
described.
[0120] As is shown in FIG. 7A, a liquid crystal display device 200
has a circuit pattern in which are formed a plurality of scan lines
(i.e., a functional layer) 201 and data lines (i.e., a functional
layer) 202 that are arranged in a matrix configuration, pixel
electrodes (i.e., a functional layer) 230, and TFT (i.e., a
functional layer) 210 used for pixel switching for controlling the
pixel electrodes 230. The scan lines 201 receive the supply of scan
signals Q1, Q2, . . . , Qm in pulses, while the data lines 202
receive the supply of image signals R1, R2, . . . , Rn. The scan
lines 201 and the data lines 202 are connected to the TFT 210 as
described below, and the TFT 210 a driven by the scan signals Q1,
Q2, . . . , Qm and the image signals R1, R2, . . . , Rn. Storage
capacitors (i.e., a functional layer) 220 that hold image signals
R1, R2 . . . , Rn of a predetermined level for a fixed period are
also formed, and capacitor wires (i.e., a functional layer) 203 are
connected to the storage capacitors 220.
[0121] Furthermore, as is shown in FIG. 7B, the TFT 210 are TFT
having what is known as a bottom gate type (i.e., a reverse stagger
type) of structure. Specifically, this structure is formed by
laminating in the following sequence an insulating substrate 200a
that forms a base material of the liquid crystal display device
200, a foundation protective film (i.e., functional layer) 2001
that is formed on a surface of the insulating substrate 200a, a
gate electrode (i.e., functional layer) 210G, a gate insulating
film (i.e., functional layer) 210I, a channel area (i.e.,
functional layer) 210C, and an insulating film (i.e., functional
layer) 211I to protect the channels. A source area (i.e.,
functional layer) 210S and a drain area (i.e., functional layer)
210D are formed on both sides of the insulating film (i.e.,
functional layer) 211I. A source electrode (i.e., functional layer)
211S and a drain electrode (i.e., functional layer) 211D are formed
on surfaces of the source and drain areas 210S and 210D.
[0122] Furthermore, an interlayer insulating film 212I and a pixel
electrode (i.e., functional layer) 230, which is made up of a
transparent electrode such as ITO are formed on the surface sides
of the source electrode 211S and drain electrode 211D. The pixel
electrode 230 is electrically connected to the drain electrode 211D
via a contact hole.
[0123] The gate electrode 210G forms a portion of a scan line 201,
while the source electrode 211S forms a portion of the data line
202.
[0124] Next, a method of manufacturing a circuit pattern of the
liquid crystal display device 200 will be briefly described.
[0125] This circuit pattern prepares as CAD data a plurality of
layers that correspond to each of the above described functional
layers. The circuit pattern then prepares bitmap data from the CAD
data and also prepares liquid droplet discharging data. In
addition, the discharging heads 3a (i.e., the discharging head
group 3) discharge liquid droplets based on this liquid droplet
discharging data. A material that corresponds to each functional
layer is used for the material liquid of these liquid droplets.
[0126] As has been described above, by employing the liquid droplet
discharging method of the present invention, it becomes possible to
form a pattern having a laminated structure.
[0127] While preferred embodiments of the invention have been
described and illustrated above, it should be understood that these
are exemplary of the invention and are not to be considered as
limiting. Additions, omissions, substitutions, and other
modifications can be made without departing from the spirit or
scope of the present invention. Accordingly, the invention is not
to be considered as limited by the foregoing description and is
only limited by the scope of the appended claims.
* * * * *