U.S. patent application number 12/926437 was filed with the patent office on 2011-03-24 for display device, apparatus for producing display device, and method for producing display device.
This patent application is currently assigned to ULVAC, INC.. Invention is credited to Toshio Negishi.
Application Number | 20110069473 12/926437 |
Document ID | / |
Family ID | 39709971 |
Filed Date | 2011-03-24 |
United States Patent
Application |
20110069473 |
Kind Code |
A1 |
Negishi; Toshio |
March 24, 2011 |
Display device, apparatus for producing display device, and method
for producing display device
Abstract
A display device free from a deterioration in luminescence
efficiency is provided. In the display device of the present
invention, since an inorganic film is formed after concave parts in
which luminescence portions are positioned are filled with a
filling film, no crack is formed in the inorganic film. Since the
inorganic film is made of a material having high gas tightness and
heat conductivity (such as, diamond-like carbon or AlN), water and
oxygen will hardly penetrate the luminescence portions, and heat of
the luminescence portions will be conducted to the inorganic film,
so that the luminescence portions do not reach high temperatures.
Further, since a gap between first and second panels is filled with
a resin film, the atmosphere does not enter from the outside.
Because the luminescence portions are free from damage from water,
oxygen and heat, the display device of the present invention has a
prolonged life.
Inventors: |
Negishi; Toshio;
(Chigasaki-shi, JP) |
Assignee: |
ULVAC, INC.
Chigasaki-shi
JP
|
Family ID: |
39709971 |
Appl. No.: |
12/926437 |
Filed: |
November 18, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12544665 |
Aug 20, 2009 |
7857673 |
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12926437 |
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PCT/JP08/52501 |
Feb 15, 2008 |
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12544665 |
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Current U.S.
Class: |
362/84 |
Current CPC
Class: |
Y10T 156/10 20150115;
H01L 51/5253 20130101; H01L 51/529 20130101; H01J 1/70 20130101;
H01L 27/3244 20130101; H01L 51/5246 20130101 |
Class at
Publication: |
362/84 |
International
Class: |
F21V 9/16 20060101
F21V009/16 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 21, 2007 |
JP |
2007-040866 |
Feb 21, 2007 |
JP |
2007-040867 |
Claims
1. A display device comprising: a first and a second panels; a
protective film; the first and second panels having surfaces
arranged opposite to each other, a laminated film having concave
parts and arranged on the surface of the first panel, and
luminescence portion of which a lower electrode, an organic film
and an upper electrode are laminated, and the luminescence portion
is positioned where the concave part is arranged; the protective
film being formed on a surface of the laminated film, the
protective film including: a filling film for filling the concave
part; an inorganic film formed on the surface of the filling film,
a resin film formed on the inorganic film, and wherein a face of
the first panel at which the concave parts are formed is made
flatter after the filling film is filled than before the filling
film is filled, and wherein the inorganic film is made of one of a
diamond-like carbon and AlN as a main component.
2-3. (canceled)
4. The display device according to claim 3, wherein each of the
luminescence portion is positioned at a light-emitting area inside
an edge of the first panel, an edge of the filling film is adhered
to the surface of the first panel outside the light-emitting area,
an edge of the inorganic film is adhered to the surface of the
first panel outside the edge of the filling film, and an edge of
the resin film is adhered to the surface of the first panel outside
the edge of the inorganic film.
5-17. (canceled)
Description
[0001] The present invention is a Continuation of International
Application No. PCT/JP2008/52501 filed Feb. 15, 2008, which claims
priority to Japan Patent Document No. 2007-040866, filed on Feb.
21, 2007 and Japan Patent Document No. 2007-040867, filed on Feb.
21, 2007. The entire disclosures of the prior applications are
hereby incorporated by reference herein in their entireties.
BACKGROUND
[0002] The present invention relates to a technical field of a
display device.
[0003] Conventionally, display devices utilizing organic EL
(Electro-Luminescence) have been widely used.
[0004] However, when organic materials used in the organic EL is in
contact with water or oxygen, the organic materials are, generally,
likely to be chemically changed. When water or oxygen enters the
interior of the display device from the atmosphere, the organic
materials are denatured, causing poor light emission.
[0005] Particularly in a display device of a top emission type, in
which a light discharged to a panel at a side opposite to the panel
of which an organic film is provided is taken out to the outside,
there are problems of difficult sealing, deterioration in
luminescence efficiency, deterioration in sealing performance with
lapse of time, etc. Such problems are described in JPA No.
2001-176655 and JPA No. 2006-286211.
SUMMARY OF THE INVENTION
[0006] The present invention, which is used to solve the
above-mentioned problems, is aimed at providing a display device
which prevents invasion of water or oxygen from the outside while
maintaining a prolonged life.
[0007] In order to solve the above problems, the present invention
is directed to a display device including first and second panels,
the first and second panels having surfaces arranged opposite to
each other, a protected film, a laminated film having concave parts
arranged on the surface of the first panel, and a luminescence
portion of which a lower electrode, an organic film and an upper
electrode are laminated. The luminescence portion is positioned
where the concave part is arranged, the protective film being
formed on a surface of the laminated film, and the protective film
includes a filling film which fills the concave part and an
inorganic film formed on a surface of the filling film in at least
at portion where the concave part is arranged, wherein a face of
the first panel at which the concave parts are formed is made
flatter after the filling film is filled than before the filling
film is filled.
[0008] The present invention is directed to the display device,
wherein the inorganic film is made of either a diamond-like carbon
or AlN as a main component.
[0009] The present invention is directed to the display device,
wherein the protective film further includes a resin film formed on
a surface of the inorganic film, and wherein the surface of the
second panel and the face of the first panel at which the inorganic
film is formed are in close contact with the resin film.
[0010] The present invention is directed to the display device,
wherein each luminescence portion is positioned at a light-emitting
area inside an edge of the first panel, an edge of the filling film
is adhered to the surface of the first panel outside the
light-emitting area, an edge of the inorganic film is adhered to
the surface of the first panel outside the edge of the filling
film, and an edge of the resin film is adhered to the surface of
the first panel outside the edge of the inorganic film.
[0011] The present invention is directed to an apparatus for
producing a display device, the apparatus includes first and second
film forming chambers, an evacuating system connected to the first
and second film forming chambers, respectively, a printing head
arranged inside the first film-forming chamber, a filling agent
feeding system with a filling agent placed therein and connected to
the printing head, a control system connected to the printing head,
and an inorganic film forming unit arranged inside the second film
forming chamber, wherein the printing head is configured to
discharge the filling agent fed from the filling agent feeding
system to a position according to positional information in the
control system, and the first and second film forming chambers are
configured so that an object to be processed can be carried from
the interior of the first film forming chamber into the second film
forming chamber without being exposed to the atmosphere.
[0012] The present invention is directed to the apparatus for
producing the display device, wherein the inorganic film forming
unit comprises first and second electrodes arranged in the second
film forming chamber, a gas feeding system for feeding hydrocarbon
gas into the second film forming chamber is connected to the second
film forming chamber, and a high frequency voltage is to be applied
between the first and second electrodes.
[0013] The present invention is directed to the apparatus for
producing the display device, wherein the inorganic film forming
unit possesses a target of an inorganic material arranged inside
the second film forming chamber, and a sputtering gas introduction
system for feeding a sputtering gas into the second film forming
chamber is connected to the inside of the second film forming
chamber.
[0014] The present invention is directed to a display device
producing method for producing a display device, the display device
including first and second panels, the first and second panels
having surfaces arranged opposite to each other, a protective film,
a laminated film having concave parts and arranged on the surface
of the first panel, and luminescence portions of which a lower
electrode, an organic film and an upper electrode are laminated and
the luminescence portion is positioned where the concave part is
arranged, with the protective film being formed on a surface of the
laminated film. The display device producing method includes the
steps of carrying the first panel on which the laminated film is
formed into the first film forming chamber; forming a filling film
by impinging a filling agent in the concave part in order to make a
face of the first panel on which the concave parts are formed to be
flatter than before the filling film is formed in the state that a
printing ambience which is at a pressure lower than the atmospheric
pressure is formed inside the first film forming chamber; and then,
forming an inorganic film on a surface of the filling film so as to
form the protective film having the filling film and the
inorganic.
[0015] The present invention is directed to the display device
producing method which further includes the steps of carrying the
first panel on which the filling layer is formed into the second
film forming chamber; arranging the first panel between first and
second electrodes inside the second film forming chamber; applying
a voltage between the first and second electrodes in the state that
a reactive ambience containing a hydrocarbon gas and having a
pressure lower than the atmospheric pressure and equal to or higher
than the printing ambience is formed inside the second film forming
chamber; and forming the inorganic film including diamond-like
carbon on a surface of the filling film.
[0016] The present invention is directed to the display device
producing method which further includes the steps of carrying the
first panel on which the filling film is formed into the second
film forming chamber; forming the inorganic film on a surface of
the filling film by sputtering a target arranged inside the second
film forming chamber in a state such that a sputtering ambience
containing a sputtering gas and having a pressure lower than the
pressure of the printing ambience is formed inside the second film
forming chamber.
[0017] The present invention is directed to the display device
producing method, wherein a target containing Al is used; and a gas
containing nitrogen in its chemical structure is incorporated into
the sputtering ambience and the sputtering is performed, thereby
forming the inorganic film containing AlN.
[0018] The present invention is directed to the display device
producing method, wherein the filling agent is impinged in the
concave parts by an ink jet method.
[0019] The present invention is directed to the display device
producing method, wherein the filling film is formed in a state
such that the content of each of oxygen and water inside the first
film forming chamber is set to 1 ppm or less; and the inorganic
film is formed in a state such that the content of each of oxygen
and water inside the second film forming chamber is set to 1 ppm or
less.
[0020] The present invention is directed to the display device
producing method which further includes, after a resin film is
formed on a surface of the first panel on which the inorganic film
is formed, the steps of making a surface of the second panel
opposed to a face of the first panel on which the resin film is
formed; and bonding the second panel to the first panel by means of
a ring-shaped sealing member surrounding the resin film in a state
such that the second panel is adhered to the resin film.
[0021] The present invention is directed to the display device
producing method further includes arranging the first panel on
which the inorganic film is formed inside a third film forming
chamber, and coating a resin liquid on a surface of the inorganic
film in the state that a coating ambience having a pressure equal
to or lower than the pressure of the reactive ambience is formed
inside the third film forming chamber in order to form the resin
film.
[0022] The present invention is directed to the display device
producing method which further includes, after a resin film is
formed on that surface of the first panel on which the inorganic
film is formed, the steps of making a surface of the second panel
opposed to that face of the first panel on which the resin film is
formed; and bonding the second panel to the first panel by a
ring-shaped sealing member surrounding the resin film in a state
such that second panel is adhered to the resin film.
[0023] The present invention is directed to the method for
producing the display device which further includes the steps of
arranging the first panel on which the inorganic film is formed in
the third film forming chamber; and coating a resin liquid on a
surface of the inorganic film so as to form the resin film in a
state such that a coating ambience having a pressure lower than the
atmospheric pressure and higher than the pressure of the sputtering
ambience is formed inside the third film forming chamber.
[0024] The gap between the first and second panels is filled with
the resin film so that water and oxygen will hardly ever enter the
interior of the display device. Because each of the luminescence
portions is covered with the inorganic film, water or oxygen does
not enter the luminescence portions even if they enter the display
device. The inorganic film composed mainly of either diamond-like
carbon or AlN (aluminum nitride) has high heat conductivity so that
the luminescence portions do not reach high temperatures or undergo
heat damage. Because both the diamond-like carbon thin film and the
AlN thin film have excellent light transparency, a light takeout
efficiency does not decrease, even when the present invention is
applied to the top emission type display device.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] FIG. 1 is a sectional view for illustrating an embodiment of
a display device of the present invention.
[0026] FIG. 2 is a sectional view for illustrating an embodiment of
the producing apparatus of the present invention.
[0027] FIGS. 3(a) to (d) are sectional views for illustrating steps
of producing a display device of the present invention.
[0028] FIG. 4 is a sectional view for illustrating a second
embodiment of the producing apparatus of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0029] In FIG. 1, reference numeral 1 generally denotes one
embodiment of the display device of the present invention.
[0030] This display device 1 includes first and second panels 10,
20, and the first and second panels 10, 20 are bonded to each other
by means of a ring-shaped sealing member 22 in a state such that
surfaces of the first and second panels 10, 20 are opposed to each
other.
[0031] The first panel 10 includes a first substrate 11. A
plurality of pixel electrodes (lower electrodes) 12 are arranged in
a matrix shape on the surface of the first substrate 11 inside the
sealing member 22. In this embodiment, an organic film 14, an
injection layer 17 and a transparent electrode film (upper
electrode) 18 are laminated to cover each pixel electrode 12; and
thereby, a laminated film 19 having the pixel electrode 12, the
organic film 14, the injection layer 17 and the transparent
electrode film 18 is formed.
[0032] Here, the transparent electrode film 18 is formed in order
to cover each pixel electrode 12; and at least a part of the
transparent electrode film 18 is extended to the outside of the
ring of the sealing member 22 and connected to a land (not shown)
arranged on the surface of the first panel 10. The land is
configured to be connectable to a terminal of an external circuit,
and a voltage is applied to the transparent electrode film 18 from
the external circuit via the land.
[0033] The pixel electrodes 12 are respectively connected to, for
example, the below-mentioned transistor 40 (for example, a TFT or a
thin film transistor). The pixel electrode 12 is selected, the
transistor 40 connected to this pixel electrode 12 is electrically
conducted, and when a voltage is applied between the pixel
electrode 12 and the transparent electrode film 18, light is
emitted at a portion of the organic film 14 located above this
pixel electrode 12 among the organic film 14.
[0034] The injection layer 17 is made of a transparent metallic
film (such as, an Ag/Mg alloy or the like), and a transparent
electrode film 18 is made of a transparent electrode film (such as
ITO (indium-tin oxide), InZnO, AZO (Al--ZnO) or the like). The
light emitted from the organic film 14 passes through the injection
layer 17 and the transparent electrode film 18.
[0035] A protective film 25 is formed on a surface of the laminated
film 19, and the protective film 25 is constituted by transparent
films (a filling film 27, an inorganic film 28, a resin film 29, or
the like), which will be discussed later. The light having passed
through the transparent electrode film 18 enters the second panel
20 through the protective film 25.
[0036] The second panel 20 has a transparent substrate (second
substrate 21) made of glass, plastic or the like. Assuming that a
portion of the laminated films 19 where the pixel electrode 12 is
positioned is taken as a luminescence portion 15, a color filter 23
of red, green or blue is provided on the surface of the second
substrate 21 at a position opposed to the luminescence portion 15.
A light entering the second panel 20 passes through the color
filter 23, and is emitted outside after being converted to a
colored light of red, green or blue.
[0037] In this way, although the display device 1 makes the organic
film 14 generate and emit a light outside, organic materials to be
used in the organic film 14 (a light-emitting material, a charge
migration material, a charge transfer material or the like) are
likely to be chemically denatured with moisture or oxygen. If such
an organic material is denatured, the amount of the emitted light
decreases, and no light is emitted in an extreme case.
[0038] In the display device 1 of the present invention, a
protective film 25 is formed on a surface of the laminated film 19,
and the protective film 25 includes a filling film 27, an inorganic
film 28 and a resin film 29.
[0039] The thickness of the laminated film 19 varies depending upon
the kinds and the film thicknesses of the thin films constituting
the laminated film 19. The portions where the luminescence portions
15 are positioned are thinner than those where the transistors 40
or the like are positioned, so that concave parts 13 are formed.
The filling film 27 is formed in order to fill the concave parts 13
at least on the respective luminescence portions 15.
[0040] For example, when the filling film 27 is formed on the
luminescence portions 15 only, the concave parts 13 become
shallower after they are filled with the filling film 27 than
before they are filled with the filling film 27. When the filling
film 27 is formed over the luminescence portion 15 and projections
therearound, the height from the surface of the filling film 27 on
the luminescence portion 15 to the surface of the filling film 27
on the projection is smaller than the height from the bottom of the
concave part 13 to the surface of the projection. In any case,
differences in level on the laminated film 19 are reduced.
[0041] The inorganic film 28 is formed on the surface of the
laminated film 19 where the differences in level are reduced by
filling the concave parts 13 with the filling film 27 so that at
least the luminescence portions 15 are covered.
[0042] The inorganic film 28 is a diamond-like carbon thin film
composed of diamond-like carbon as a major component or an AlN thin
film composed of AlN as a major component. Note that "composed . .
. as a major component" in the present invention means that the
material as the major component is contained in 50% by weight or
more.
[0043] Both the diamond-like carbon thin film and the AlN thin film
not only have high transparency, but also higher gas tightness as
compared to resin films or the like. Therefore, water or oxygen
does not pass through the inorganic film 28 so that water or oxygen
does not enter the luminescence portion 15 from the upper side.
[0044] In this embodiment, the inorganic film 28 is continuously
formed to cover each of the luminescence portions 15, and the edge
portion of the inorganic film 28 is adhered to the surface of the
first panel 10 between the area where each luminescence portion 15
is arranged and inside of the inner periphery of the sealing member
22. Therefore, neither water nor oxygen enters the luminescence
portion 15 from the sides.
[0045] In addition, because both diamond-like carbon and AlN have
heat conductivity, the luminescence portion 15 does not reach a
high temperature or undergo heat damage through heat being
conducted to the inorganic film 28, even if the luminescence
portion 15 generates the heat due to light emission.
[0046] If the inorganic film 28 is formed on a portion having a
large difference in level, a crack is likely to be formed. As
discussed above, because the inorganic film is formed after the
concave parts 13 are filled with the filling film 27, each of the
luminescence portions 15 is kept covered with the inorganic film
28.
[0047] In addition, when the concave part 13 is reduced or
eliminated, the inorganic film 28 can be formed by a sputtering
method without good coverage. Consequently, the dense inorganic
film 28 can be formed by the sputtering method.
[0048] The resin film 29 fills an inner space surrounded by the
sealing member 22 and the first and second panels 10, 20 without a
gap, and adheres to the inner peripheral face of the sealing member
22, the surface of the second panel 20, the surface of the
inorganic film 28, and that portion of the first panel 10 which is
exposed from the inorganic film 28. Because no gap exists in the
inner space, air hardly enters from the outside.
[0049] Here, the filling film 27 covers all the areas where each
luminescence portion 15 is positioned (the light emitting area);
the inorganic film 28 covers all the surface of the filling film
27; and the resin film 29 is formed to cover all the surface of the
inorganic film 28. The edge of filling film 27 adheres to the first
panel 10 outside the light emitting area, the edge of the inorganic
film 28 adheres to the first panel 10 outside the filling film 27,
and the edge of the resin film 29 adheres to the first panel 10
outside the inorganic film 28. Therefore, the surface and the
peripheral face of the light emitting area is covered in three
areas; namely, the filling film 27, the inorganic film 28 and the
resin film 29 so that water and oxygen hardly invade.
[0050] Next, the producing apparatus of the present invention to be
used for the production of the above-mentioned display device and
the producing method of the present invention for the production of
the display device 1 will be explained.
First Embodiment of the Producing Apparatus
[0051] In FIG. 2, a reference numeral 5 denotes a first embodiment
of the producing apparatus of the present invention. The producing
apparatus 5 includes first to third film forming chambers 51 to
53.
[0052] An evacuation system 69 is connected to the first to third
film forming chambers 51 to 53, respectively, and when the
interiors of the first to third film forming chambers 51 to 53 are
evacuated by the evacuating system 69, pressure-reduced ambience
having pressures lower than the atmospheric pressure
(1.01325.times.10.sup.5 Pa=760 Torr) are formed inside the first to
third film forming chambers 51 to 53.
[0053] The first to third film forming chambers 51 to 53 are
connected to one another directly or via other vacuum chambers (a
buffer chamber, a transfer chamber or the like), and an object to
be processed by this producing apparatus 5 is carried among the
first to third film forming chambers 51 to 53 by a transfer unit
(not shown) without being exposed to the atmosphere.
[0054] A printing table 55 on which the object to be processed is
placed is arranged inside the first film forming chamber 51; and a
printing head 56 is arranged at a position above the printing table
55 inside the first film forming chamber 51.
[0055] A transfer mechanism (not shown) is arranged inside the
first film forming chamber 51, either one or both of the objects
placed on the printing table 55 and the printing head 56 are to be
moved by the transfer mechanism (not shown). Therefore, the
printing head 56 and the object to be processed move relative to
each other.
[0056] A, filling agent feeding system 58 and a control system 57
are arranged outside the first film forming chamber 51. The filling
agent feeding system 58 and the control system 57 are connected to
the printing head 56, respectively, while the filling agent feeding
system 58 feeds a liquid filling agent to the printing head 56; and
the control system 57 is configured to detect a positional
relationship between the printing head 56 and the object to be
processed and causes the filling agent to be discharged through a
nozzle when the nozzle of the printing head 56 is positioned above
a desired position of the object to be processed (Ink jet
method).
[0057] A heater (not shown) is provided inside the first film
forming chamber 51; the filling agent impinged upon the object to
be processed is heated by the heater; and a solvent in the filling
agent is evaporated away in order to remove it.
[0058] An inorganic film forming unit 60 is arranged inside the
second film forming chamber 52. In the first embodiment of the
producing apparatus 5, the inorganic film forming unit 60 includes
first and second electrodes 61 and 62, which are arranged inside
the second film forming chamber 52.
[0059] In this embodiment, the first and second electrodes 61, 62
are flat electrodes, which are arranged horizontally inside the
second film forming chamber 52 in a state such that the first and
second electrodes 61, 62 are parallel to each other. The object to
be processed is placed on the surface of the second electrode 62
opposed to the first electrode 61.
[0060] Meanwhile, the first and second electrodes 61, 62 may be
inclined from the horizontal plane, respectively, so long as the
object to be processed is held on the second electrode 62.
[0061] A power source 65 and a raw material gas feeding system 64
are arranged outside the second film forming chamber 52. The first
and second electrodes 61, 62 are connected to the power source 65,
respectively. When a high frequency voltage is applied between
first and second electrodes 61, 62 in a state such that the second
film forming chamber 52 is connected to a ground potential, while a
raw material gas is being fed from the raw material gas feeding
system 64, a plasma of the raw material gas is generated, and a
polymer of the raw material gas is formed on the surface of the
object to be processed.
[0062] Meanwhile, when one of the first and second electrodes 61,
62 is set at the ground potential, a high frequency voltage may be
applied to set the other electrode at a negative or positive
voltage relative to the ground potential. Alternatively, when one
of the electrodes is set at a negative voltage relative to the
ground potential, a high frequency voltage may be applied to set
the other electrode at a positive voltage relative to the ground
voltage. Further, the high frequency voltage may be applied to the
other electrode in a state such that one of the electrodes is
connected to the ground potential.
[0063] A mounting table 72 and a screen 74 are arranged inside the
third film forming chamber 53, the object to be processed, which is
carried inside the third film forming chamber 53, is then placed on
the mounting table 72, and the screen 74 is arranged above the
object by means of a spacer 73, while being spaced therebetween by
a predetermined distance.
[0064] A nozzle 77 and a pressing means 78 are arranged above the
screen 74, respectively. The nozzle 77 is connected to a resin
liquid feeding system 76, and a resin liquid fed from the resin
liquid feeding system 76 is discharged onto a surface of the screen
74 through the nozzle 77.
[0065] The pressing means 78 is a pressing roll or a squeegee,
which can be horizontally and reciprocatively moved on the screen
74. A plurality of through-holes (not shown) are formed in the
screen 74, and when the pressing means 78 is moved forward, the
resin liquid is spread over the surface of the screen 74 and forced
into the through-holes. When the pressing means is moved backward,
the resin liquid is further forced into the through-holes, and the
resin liquid is pushed out through the through-holes and dropped
toward the object to be processed.
First Example of the Producing Method
[0066] Next, the steps of producing the display device of the
present invention by using the first embodiment of the producing
apparatus 5 will be explained.
[0067] First, the first and third film forming chambers 51, 53 are
preliminarily vacuum evacuated. In this embodiment, the gas feeding
system 68 is connected to the first to third film forming chambers
51 to 53. While the first and third film forming chambers 51, 53
are being continuously vacuum evacuated, an inert gas (for example,
a dried N.sub.2 gas) with the content of each of water and oxygen
being 1 ppm or less, respectively, is fed into the first and third
film forming chambers 51, 53 from the gas feeding system 68, so
that pressure-reduced ambience having a pressure lower than the
atmospheric pressure with the content of each of water and oxygen
being 1 ppm or less (a printing ambience, a coating ambience) is
formed therein, respectively (Pre-processing step).
[0068] Next, a step of forming the filling film will be explained.
FIG. 3(a) denotes the first panel 10 before the filling film 27 is
formed, and each luminescence portion 15 is exposed in this state.
While the printing ambience inside the first film forming chamber
51 is being maintained, the first panel 10 in the state shown in
FIG. 3(a) is carried into the first film forming chamber 51 and
placed on the printing table 55.
[0069] A filling agent of which a transparent resin is dissolved in
a solvent is preliminarily filled in the filling agent feeding
system 58.
[0070] Positional information of the luminescence portions 15 is
preliminarily inputted in the control system 57, and while the
printing ambience is being maintained, the first panel 10 and the
printing head 56 are relatively moved by the control system 57.
After the concave parts 13 are filled with the filling agent by
impinging the filling agent upon each of the luminescence portions
15 according to the positional information in the control system
57, the filling film 27 filling the concave parts 13 is formed by
drying the filing agent with the heater.
[0071] In this case, the positional information may be inputted
directly into the control system 57, or the positional information
may be inputted into the control system 57 by connecting another
device in which the positional information is already
memorized.
[0072] In the filling film forming step, the resin liquid (the
filling agent) may be so impinged as to not overflow from the
concave parts 13, while projections around the concave parts 13 are
exposed from the filling film 27. Furthermore, in the filling film
forming step, as shown in FIG. 3(b), it may be that the resin
liquid is so impinged as to overflow from the concave parts 13 and
cover the projections around the concave parts 13 with the filling
film 27 and the area, where each luminescence portion 15 is
positioned, is covered with a single continuous filling film
27.
[0073] Next, a step of forming the inorganic film will be
explained.
[0074] In this embodiment, the raw material gas feeding system 64
includes a raw material gas tank in which at least one kind of raw
material gases selected from a hydrocarbon group consisting of
CH.sub.4, C.sub.6H.sub.6 and C.sub.2H.sub.2 is charged; and a
diluent gas tank in which an inert gas (such as, an Ar gas or the
like) is charged.
[0075] The interior of the second film forming chamber 52 is vacuum
evacuated, and once set at a high vacuum. Then, after a byproduct
or the like produced when the previous panel is produced is
evacuated, the inert gas is introduced from the gas feeding system
68, and the raw material gas and the diluent gas are introduced
from the raw material feeding system 64, so that a reactive
ambience having a pressure lower than the atmospheric pressure with
the content of each of water and oxygen being 1 ppm or less is
preliminarily formed.
[0076] While the reactive ambience is being maintained, the first
panel 10 on which the filling film 27 is formed is carried into the
inside of the second film forming chamber 52 and placed on the
surface of the second electrode 62.
[0077] A mask (not shown) is arranged on the first panel 10 such
that an edge portion of the first panel 10 is covered with the
mask, while at least the areas where the luminescence portions are
arranged are exposed through the inside of the through-holes. When
a high frequency voltage is applied between the first and second
electrodes 61, 62, the inorganic film 28 made of a polymer of the
hydrocarbon (diamond-like carbon) grows on the surface of the resin
film 27 on each luminescence portion 15 (FIG. 3(c)).
[0078] In the inorganic film forming step of the first example of
the producing method and a second example of the producing method
as discussed later, the entire filling film 27 and the surround
portion of the filling film 27 are exposed to the interior of the
through-holes formed on the mask; and the inorganic film 28 is
formed to cover the entire surface of the filling film 27 and the
surrounding portion of the filling film 27 of the surface of the
first panel 10 surrounding the filling film 27.
[0079] As discussed above, the concave parts 13 where the
luminescence portion 15 is positioned are filled with the filling
film 27 so that differences in level between the surrounding
projections are reduced. Thus, the inorganic film 28 grown on the
luminescence portions 15 is not separated from the inorganic film
28 grown on the region surrounding the luminescence portions 15;
and each luminescence portion 15 is covered with the single
continuous inorganic film 28. When the thickness of the inorganic
film 28 reaches a predetermined film thickness, the application of
the voltage between the first and second electrodes 61, 62 is
stopped.
[0080] Next, a step of forming a resin film will be explained.
[0081] As discussed above, the coating ambience having a pressure
lower than the atmospheric pressure is preliminarily formed inside
the third film forming chamber 53. While the coating ambience is
being maintained, the first panel 10 on which the inorganic film 28
is formed is carried into the third film forming chamber 53 and
placed horizontally on the mounting table 72. The screen 74 is
horizontally placed above the surface of the first panel 10.
[0082] When the pressing means 78 is moved forward while the
coating ambience is being maintained, the resin liquid is defoamed
as it spreads on the screen 74 and air remaining in the resin
liquid is removed because the pressure of the coating ambience is
lower than the atmospheric pressure.
[0083] Therefore, the resin liquid from which air is removed enters
the through-holes of the screen 74; and when the pressing means 78
is moved backward, that resin liquid drops onto the surface of the
first panel 10 through the through-holes.
[0084] The screen 74 is made of a material having a low flexibility
(such as, a metallic plate or the like), and its thickness is set
so that it may not be bent even by pressing with the pressing means
78.
[0085] Thus, the height of the screen 74 from the surface of the
first substrate 11 is maintained at a predetermined height.
[0086] Since the resin liquid dropping through the through-holes of
the screen 74 fills a gap between the first panel 10 and the screen
74, even if a difference in level exists at the surface of the
panel 10, that difference in level is buried with the resin liquid
so that a coated layer having a uniform height from the first
substrate 11 to the surface of coated layer is formed.
[0087] In this embodiment, the resin liquid includes a
photo-polymerizable resin (such as an acrylate or the like); and
when the coated layer is irradiated with ultraviolet rays, the
coated layer is cured through the polymerization of the
photo-polymerizable resin so that the resin film 29 having a
uniform thickness from the first substrate 11 to the surface of the
coated layer is formed (FIG. 3(d)).
[0088] As discussed above, while the object to be processed (the
first panel) is carried among the first to third film forming
chambers 51 to 53, the first panel 10 is not exposed to the
atmosphere, and in addition, each of the printing ambience, the
reactive ambience and the coating ambience includes 1 ppm or less
of each of oxygen and water. Accordingly, neither oxygen nor water
is mixed into the protective film 25 composed of the filling film
27, the inorganic film 28, and the resin film 29.
[0089] Next, a sealing step will be explained.
[0090] The first panel 10 of which the protective film 25 is formed
is taken out from the third film forming chamber 53, and carried
out to the outside of the producing apparatus 5.
[0091] The ring-shaped sealing member is arranged along the outer
periphery of the resin film 41 on the surface of the first panel 10
in which the resin film 29 is formed in order to form the sealing
member so as to be in close contact with the peripheral face of the
resin film 29.
[0092] While the height of the ring of the sealing member is set at
the same as or greater than the height from the surface of the
first substrate 11 to the surface of the resin film 29, the second
panel 20 is placed on the first panel 10. After alignment is
performed to make the color filter 23 to be opposed to a
predetermined luminescence portion 15, the second panel 20 is
lowered and is in contact with the sealing member.
[0093] The sealing member is made of an adhesive material (such as
glass, a resin or the like) so that when the sealing member is
heated while the second panel 20 is being pressed, the sealing
member is softened and adhered to both the first and second panels
10, 20. Further, when the pressing is continued under heating, the
softened sealing member is crushed by pressing; the second panel 20
is adhered to the resin film 29; and a space surrounded by the
first and second panels 10, 20 and the sealing member is filled
with the resin film 29 without a gap. Next, when the sealing member
is solidified by cooling, the first and second panels 10, 20 are
bonded together by the sealing member, thereby obtaining a display
device 1 as shown in FIG. 1.
[0094] In the first example of the producing method and the
below-mentioned second example of the producing method, the
pressure of the printing ambience is not particularly limited, so
long as the pressure is the same as the atmospheric pressure or
less. When the resin liquid is coated by the ink jet method, for
example, a reduced ambience of around 400 Torr
(533.3.times.10.sup.2 Pa when converted to Pa) is preferable. It is
noted that when both a Torr value and a converted Pa value thereof
are described together, preference is given to the Torr value over
the Pa value.
[0095] The method of forming the inorganic film 28 is not
particularly limited. However, because the ink jet method cannot be
performed under high vacuum (for example, 200 Torr or more), a
difference in pressure between the first and second film forming
chambers 51, 52 becomes too large in a film forming method, such
as, a sputtering method requiring high vacuum (for example,
5.times.10.sup.-3 Torr). Thus, dust is generated when the object to
be processed is carried from the first film forming chamber
directly to the second film forming chamber 52; and consequently,
contamination of the dust into the protective film 25 occurs. Such
a problem is avoided if a pressure adjusting buffer chamber is
provided between the first and second film forming chambers 51; 52,
but the structure of the producing apparatus 5 becomes
complicated.
[0096] As discussed above, in the first example of the producing
method, the raw material gas is converted to plasma to form the
inorganic film. In this inorganic film forming method, because the
film can be formed at, for example, 400 Torr (533.3.times.10.sup.2
Pa when converted to Pa), the pressure difference between the first
and second film forming chambers 51, 52 becomes smaller as compared
to the sputtering method. Therefore, no dust is generated even if
the first and second film forming chambers 51, 52 are directly
connected without the use of the buffer chamber.
[0097] The pressure of the coating ambience is not particularly
limited, so long as the pressure is the same as the atmospheric
pressure or less. However, in order to effectively defoam the resin
liquid, the pressure is in the range of 250 Torr or more and 760
Torr or less; i.e., in the range of 333.3.times.10.sup.2 Pa or more
and 1013.2.times.10.sup.2 Pa or less when converted to Pa.
[0098] By an inorganic film forming method in which the raw
material gas is converted to plasma, the pressure difference
between the second and third film forming chambers 52, 53 is
decreased so that no dust is mixed into the protective film 25 even
if the second and third film forming chambers 52, 53 are directly
connected.
[0099] Next, a second embodiment of the producing apparatus and a
second example of the producing method of the present invention
will be explained.
Second Embodiment of the Producing Apparatus
[0100] In FIG. 4, a reference numeral 6 denotes a producing
apparatus of a second embodiment. The producing apparatus 6 of the
second embodiment has the same construction as in the producing
apparatus 5 of the first embodiment, except that an inorganic film
forming unit 90 and a gas feeding system 94 connected to the second
film forming chamber 52 are different. The same reference numerals
are provided for the same parts as those in the producing apparatus
5 of the first embodiment, and a corresponding explanation is
omitted.
[0101] The inorganic film forming unit 90 of the producing
apparatus 6 of the second embodiment has a target 91; and the
target 91 is arranged inside the second film forming chamber
52.
[0102] A power source 95 and a gas feeding system 94 are arranged
outside the second film forming chamber 52; and the target 91 is
connected to the power source 95. In the producing apparatus 6 of
the second embodiment, the gas feeding system 94 is a sputtering
gas feeding system in which a sputtering gas is disposed.
[0103] The interior of the second film forming chamber 52 is vacuum
evacuated by an evacuating system 69, and while the sputtering gas
is being fed from the sputtering gas feeding system 94 to the
second film forming chamber 52, the target 91 is sputtered by
applying a voltage to the target 91 from the power source 95 in a
state such that second film forming chamber 52 is set at a ground
potential.
[0104] In the producing apparatus 6 of the second embodiment, the
second film forming chamber 52 is connected to each of the first
and third film forming chambers 51, 53 via a vacuum chamber (not
shown), for example, buffer chamber.
[0105] Even if the pressure difference between the second film
forming chamber 52, and the first and third film forming chambers
51, 53 is large, no dust is generated because the inner ambience of
the second film forming chamber 52 is not directly connected to the
first or third film forming chamber 51, 53.
[0106] Next, a second example of the producing method by using the
producing apparatus 6 of the second example as described above will
be explained.
A Producing Method of a Second Example
[0107] A producing method of a second example of the invention is
the same as the producing method of the first example of the
invention in terms of the pre-processing process and the filling
film forming step. In the above-discussed steps, a filling film 27
is formed on a surface of a first panel 10.
[0108] Next, an inorganic film forming step of the producing method
of the second example will be explained.
[0109] In this example, the sputtering gas feeding system 94
includes a sputtering gas tank in which a sputtering gas such as Ar
gas or Ne gas is disposed and a reactive gas tank in which a
reactive gas (here, nitriding gas made of N.sub.2) is disposed.
[0110] A vacuum ambience is formed by vacuum evacuating the
interior of the second film forming chamber 52 by means of the
evacuating system 69; and while this vacuum ambience is being
maintained, the first panel 10 formed with the filling film 27 is
carried into the second film forming chamber 52.
[0111] In this method, the substrate holder 92 is arranged inside
the second film forming chamber 52, the first panel 10 carried into
the second film forming chamber 52 is placed on the substrate
holder 92, and that face of the first panel 10 on which the filling
film 27 is formed is opposed to the target 91.
[0112] While the interior of the second film forming chamber 52 is
continuously vacuum evacuated, the sputtering gas and the reactive
gas are fed from the sputtering gas feeding system 94, thereby
forming a sputtering ambience having a pressure lower than the
pressure of the printing ambience. For example, the pressure of the
printing ambience is 400 Torr (533.3.times.10.sup.2 Pa when
converted to Pa); and the pressure of the sputtering ambience is
5.times.10.sup.-3 Torr (6.67.times.10.sup.-1 Pa when converted to
Pa). It is noted that when the Torr value and the converted Pa
value are given together in the specification of this application,
preference is given to the Torr value over the Pa value.
[0113] A mask (not shown) is arranged on the first panel 10 to
cover an edge portion of the first panel 10 therewith; and the
target 91 is sputtered in a state such that at least an area in
which the luminescence portions 15 are disposed is exposed inside
the through-hole of the mask while the sputtering ambience is being
maintained.
[0114] The target 91 is an Al target composed mainly of Al, and the
reactive gas is a nitriding gas containing a nitrogen atom in a
chemical structure (for example, N.sub.2) so that an inorganic film
28 composed of aluminum nitride (AlN) grows on a surface of the
filling film 27 on each luminescence portion 15 (FIG. 3(c)).
[0115] In this example, the sputtering is performed in a state such
that the entire filling film 27 and the surrounding of the filling
film 27 are exposed to the interior of the through-hole of the
mask, thereby an inorganic film 28 is formed to cover the entire
surface of the filling film 27 and the surrounding portion of the
filling film 27 on the surface of the first panel 10.
[0116] In the sputtering, if a difference in level exists on the
object to be formed with the film, the formed film is more likely
to be divided as compared with other film forming method (such as,
CVD, vapor deposition or the like).
[0117] As discussed above, the concave parts 13 where the
luminescence portions 15 are positioned are filled with the filling
film 27, and the difference in level between the concave parts 13
and the surrounding projections are reduced. Thus, the inorganic
film 28 grown on the luminescence portions 15 and the inorganic
film 28 grown on the region surrounding the luminescence portion
are not divided, and each luminescence portion 15 is covered with a
single continuous inorganic film 28. When the thickness of the
inorganic film 28 reaches a predetermined film thickness, the
application of the voltage to the target 91 is stopped.
[0118] Next, a resin film is formed by performing a resin film
forming step under the same condition as in the above first example
of the producing method.
[0119] Meanwhile, since the sputtering ambience is a high vacuum,
and if the coating ambience in forming the resin film is set at a
high vacuum equivalent to the sputtering ambience, it becomes
difficult to control the pressure inside the resin liquid feeding
system 76. Therefore, the coating ambience is set at a pressure,
which is higher than the pressure of the sputtering ambience and
lower than the atmospheric pressure.
[0120] After the formation of the resin film, when the first and
second panels are sealed by the same method as in the sealing step
of the first example of the producing method, the display device 1
is obtained.
[0121] As mentioned above, in the second example of the producing
method, the sputtering ambience is set at high vacuum of around
5.times.10.sup.-3 Torr. To the contrary, the pressure of the
printing ambience is in the range of 200 Torr or more and the
atmospheric pressure (for example, around 400 Torr) or less, and
the pressure of the coating ambience is 250 Torr or more and 760
Torr or less (333.3.times.10.sup.2 Pa or more and
1013.2.times.10.sup.2 Pa or less when converted to Pa).
[0122] In other words, the inner pressure of the second film
forming chamber 52 is far lower than the inner pressures of the
first and third film forming chambers 51, 53, so that when the
second film forming chamber 52 is connected directly to the first
and third film forming chambers 51, 53, dust may be generated due
to the pressure difference.
[0123] The dust generation will be suppressed, if the pressure
difference is lowered by increasing the inner pressure of the
second film forming chamber 52 or by decreasing the inner pressures
of the first and third film forming chambers 51, 53 before the
second film forming chamber 52 is connected to the first and third
film forming chambers 51, 53. However, it takes a long time to
adjust the pressures, which makes a time period required for the
production longer.
[0124] In order to suppress the generation of the dust and to
shorten the production time period, other vacuum chambers (buffer
chambers) are disposed between the first and second film forming
chambers 51, 52 and between the second and third film forming
chambers 52, 53, respectively.
[0125] When the object to be processed (first panel) is carried
from the first film forming chamber 51 to the second film forming
chamber 52, an inner ambience having a pressure almost equal to the
pressure of the first film forming chamber 51 is formed in the
buffer chamber between the first and second film forming chambers
51, 52 in a state such that the buffer chamber between the first
and second film forming chambers 51, 52 is blocked from the second
film forming chamber 52 and the first panel 10 is carried from the
first film forming chamber 51 to the buffer chamber.
[0126] After the first film forming chamber 51 is blocked from the
buffer chamber, the buffer chamber is vacuum evacuated, and thereby
its inner pressure is reduced to almost the same pressure as the
inner pressure of the second film forming chamber 52. Then, the
buffer chamber is connected to the second film forming chamber 52,
and the first panel 10 is carried from the buffer chamber into the
second film forming chamber 52.
[0127] When the first panel 10 is to be carried from the second
film forming chamber 52 into the third film forming chamber 53, an
inner ambience, which has almost the same pressure as the inner
pressure of the second film forming chamber 52, is formed inside
the buffer chamber between the second and third film forming
chambers 52, 53, in a state such that the buffer chamber is blocked
from the third film forming chamber 53, and the first panel 10 is
carried from the second film forming chamber 52 into the buffer
chamber.
[0128] The second film forming chamber 52 is blocked from the
buffer chamber, the pressure inside the buffer chamber being raised
by the introduction or the like of a dried inert gas (the content
of each of oxygen and water being 1 ppm or less) or the like, so
that the pressure is set at a level almost equal to the inner
pressure of the third film forming chamber 53. Then, the buffer
chamber is connected to the third film forming chamber 53, and the
first panel 10 is carried from the buffer chamber into the third
film forming chamber 53.
[0129] In this way, when the carriage between the first and second
film forming chamber 51, 52 and the carriage between the second and
third film forming chamber 52, 53 are performed through the buffer
chambers, the generation of the dust is suppressed in order to
prevent the contamination of the first panel 10.
[0130] Meanwhile, in the second example of the producing method,
the method for producing the inorganic film 28 is not particularly
limited, and, a sputtering method is preferable when a thin film of
aluminum nitride is formed as the inorganic film 28. Further, the
inorganic film 28 can be formed by sputtering an AlN target without
a reactive gas being fed into the sputtering ambience.
[0131] In addition, the constituting material of the inorganic film
28 is not limited to AlN in the second example of the producing
method. By sputtering a target 91 containing at least any one kind
of inorganic materials selected from the group consisting of Al,
AlN, metal compounds (including oxides and nitrides) other than AlN
and metals, an inorganic film 28 containing at least any one kind
of the inorganic materials selected from the group consisting of
Al, AlN, the metal compounds other than AlN and the metal can be
formed.
[0132] The reactive gas in forming the film of AlN is not limited
to N.sub.2 and nitriding gases, which contains nitrogen in the
chemical structure, can be widely used. As the nitriding gas other
than N.sub.2, ammonia is recited, for example.
Other Examples
[0133] In the first and second examples of the producing method,
the filling agent coating method for forming the filling film 27 is
not particularly limited. However, an ink jet method is the most
preferable so as to accurately coat the filling agent on each of
the luminescence portions 15. In coating the filling agent by the
ink jet method, if the viscosity of the resin liquid is too high,
nozzle clogging will occur so that its viscosity is preferably 10
cP (centipoises) or less.
[0134] In the first and second examples of the producing method,
the resin to be incorporated into the filling agent is not
particularly limited, and various resins (such as, a thermoplastic
resin, a thermosetting resin, a photopolymerizable resin, etc.) can
be used. In a case such that the thermosetting resin is
incorporated into the filling agent, when the impinged filling
agent is heated so that the thermosetting resin may be polymerized,
the filling film 27 including the polymer of the thermosetting
resin is formed. In a case such that the filling agent includes the
photopolymerizable resin, after the filling agent is impinged and
the solvent is evaporated off, the filling film 27 containing the
polymer of the photopolymerizable resin can be obtained by
irradiating light.
[0135] In the first and second examples of the producing method, a
filling agent containing an inorganic material can be used. If a
water capturing agent having water capturability is used as an
inorganic material, not only does the filling film 27 reduce the
difference in level but also captures moisture entering the display
device 1 so that the organic film 14 becomes less damaged. As the
water capturing agent, a metallic complex of aluminum, for example,
is as shown below by the following formula (1):
##STR00001##
[0136] This metallic complex of aluminum chemically adsorbs water,
opens a 6-membered ring, and captures water through the formation
of 3 (R--O--Al (OH).sub.2). This metallic complex of aluminum is
not only excellent in water capturability, but also provides
excellent transparency when the film is formed. Thus, it is
particularly suitable for the display device 1 of the top emission
type.
[0137] As the filling agent containing the above described water
capturing agent, the agent with the trade name "OleDry"
manufactured by Futaba Corporation in which the above metallic
complex of aluminum is dissolved in a hydrocarbon-based organic
solvent can be used.
[0138] Further, when a filling agent containing both the
above-mentioned resin and the water capturing agent of the
inorganic material is used in the first and second examples of the
producing method, a filling film 27 containing both the
above-mentioned resin and the water capturing agent can be
formed.
[0139] In the first and second examples of the producing method,
the coating method of the resin liquid in the resin film forming
step is not particularly limited, and a screen printing method
using the above-mentioned screen is more preferable than an ink jet
method in order to coat such a large amount of the resin liquid for
filling the gap between the first and second panels 10, 20. The
viscosity (e.g., 100,000 cp) of the resin liquid suitable for the
screen printing method is higher than in the ink jet method.
[0140] In the first and second examples of the producing method,
the resin to be included into the resin liquid is not particularly
limited; however, the thermoplastic resin and the thermosetting
resin can be used as in the case of the filling agent. When the
resin liquid contains the thermosetting resin, the resin film 29
containing the polymer of the thermosetting resin is formed by
heating the coated layer so as to polymerize the thermosetting
resin.
[0141] In the first and second examples of the producing method,
the step of solidifying the coated layer may be performed until the
sealing member 22 is disposed after the resin liquid is coated, or
it may be simultaneously performed when bonding the first and
second panels 10, 20 together by the sealing member 22. The step of
solidifying the coated layer may be performed after the first and
second panels 10, 20 are bonded together with the sealing member
22. However, when the solidification is performed after they are
bonded together by the sealing member 22, the solvent evaporated
from the coated layer is sealed between the first and second panels
10, 20 so that the organic film 14 is damaged by the solvent.
Therefore, it is preferable to perform the step of solidifying the
coated film before the first and second panels 10, 20 are bonded
together.
[0142] As described above, explanation has been provided for the
top-emission type display device, which emits the light discharged
toward the second panel 20 side from the organic film 14. However,
the present invention is not limited thereto. The display device of
the present invention may be a bottom type display device in which
a first substrate 11 is made of a transparent substrate (such as, a
glass substrate, a plastic substrate or the like); pixel electrodes
12 are made of a transparent electrode of ITO, AZO or the like; and
the light discharged toward the first substrate 11 side from an
organic film 14 is emitted outside through the pixel electrodes 12
and the first substrate 11. In the case of the bottom-emission type
display device, the filling film 27, the inorganic film 28 and the
resin film 29 may be made of opaque materials.
[0143] In this case, the color filters may be provided at the first
substrate 11. Meanwhile, light colored with the organic film may be
emitted by adding a coloring agent in the organic film in each of
the luminescence portions 15 without the color filters.
* * * * *