U.S. patent application number 15/425902 was filed with the patent office on 2017-05-25 for display device and manufacturing method thereof.
The applicant listed for this patent is Samsung Display Co., Ltd.. Invention is credited to Kwang-Chul JUNG, Dae Ho LEE, Seon Uk LEE, Sun Hwa LEE, Sung Hwan WON.
Application Number | 20170146837 15/425902 |
Document ID | / |
Family ID | 51984720 |
Filed Date | 2017-05-25 |
United States Patent
Application |
20170146837 |
Kind Code |
A1 |
LEE; Seon Uk ; et
al. |
May 25, 2017 |
DISPLAY DEVICE AND MANUFACTURING METHOD THEREOF
Abstract
A display device may include a first subpixel electrode; a first
roof layer; a first liquid crystal layer disposed between the first
subpixel electrode and the first roof layer; and a first support
member overlapping a first end portion of the first roof layer in a
first direction. The display device may further include a second
subpixel electrode immediately neighboring the first subpixel
electrode; a second roof layer; a second liquid crystal layer
disposed between the second subpixel electrode and the second roof
layer; and a second support member overlapping a first end portion
of the second roof layer in the first direction. The first end
portion of the first roof layer and the first end portion of the
second roof layer may be disposed between a second end portion of
the first roof layer and a second end portion of the second roof
layer.
Inventors: |
LEE; Seon Uk; (Seongnam-si,
KR) ; WON; Sung Hwan; (Suwon-si, KR) ; LEE;
Dae Ho; (Seoul, KR) ; LEE; Sun Hwa;
(Andong-si, KR) ; JUNG; Kwang-Chul; (Seongnam-si,
KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Samsung Display Co., Ltd. |
Yongin-si |
|
KR |
|
|
Family ID: |
51984720 |
Appl. No.: |
15/425902 |
Filed: |
February 6, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
14151727 |
Jan 9, 2014 |
9575372 |
|
|
15425902 |
|
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G02F 1/1339 20130101;
G02F 1/133345 20130101; G02F 1/13392 20130101; G02F 1/134309
20130101; G02F 2001/134345 20130101; G02F 1/133308 20130101; G02F
1/1341 20130101; G02F 1/133377 20130101 |
International
Class: |
G02F 1/1341 20060101
G02F001/1341; G02F 1/1343 20060101 G02F001/1343; G02F 1/1339
20060101 G02F001/1339; G02F 1/1333 20060101 G02F001/1333 |
Foreign Application Data
Date |
Code |
Application Number |
May 31, 2013 |
KR |
10-2013-0063042 |
Claims
1. A method for manufacturing a display device, the method
comprising: forming a first subpixel electrode and a second
subpixel electrode, the second subpixel electrode immediately
neighboring the first subpixel electrode without any subpixel
electrode being disposed between the first subpixel electrode and
the second subpixel electrode; forming a first roof layer and a
second roof layer; forming a first support member and a second
support member, wherein the first support member overlaps a first
end portion of the first roof layer in a first direction, wherein
the second support member overlaps a first end portion of the
second roof layer in the first direction, and wherein the first end
portion of the first roof layer and the first end portion of the
second roof layer are disposed between a second end portion of the
first roof layer and a second end portion of the second roof layer;
and forming a first cavity and a second cavity, wherein a portion
of the first cavity is positioned between the first subpixel
electrode and the first roof layer, and wherein a first portion of
the second cavity is positioned between the second subpixel
electrode and the second roof layer.
2. The method of claim 1, wherein the second end portion of the
first roof layer does not overlap, in the first direction, any
support member that is analogous to the first support member or the
second support member, and wherein the second end portion of the
second roof layer does not overlap, in the first direction, any
support member that is analogous to the first support member or the
second support member.
3. The method of claim 1, further comprising: forming a third
subpixel electrode, which immediately neighbors the second subpixel
electrode without any subpixel electrode being disposed between the
second subpixel electrode and the third subpixel electrode, wherein
the second subpixel electrode is disposed between the first
subpixel electrode and the third subpixel electrode, wherein the
second roof layer overlaps both the second subpixel electrode and
the third subpixel electrode, wherein a second portion of the
second cavity is positioned between the third subpixel electrode
and the second roof layer, wherein a center portion of the second
roof layer is disposed between the first end portion of the second
roof layer and the second end portion of the second roof layer, and
wherein the center portion of the second roof layer does not
overlap, in the first direction, any support member that is
analogous to the first support member or the second support
member.
4. The method of claim 3, further comprising: forming a fourth
subpixel electrode, which immediately neighbors the third subpixel
electrode without any subpixel electrode being disposed between the
third subpixel electrode and the fourth subpixel electrode; forming
a third roof layer, which overlaps the fourth subpixel electrode in
the first direction; and forming a third cavity, wherein a portion
of the third cavity is positioned between the fourth subpixel
electrode and the third roof layer, wherein the third subpixel
electrode is disposed between the second subpixel electrode and the
fourth subpixel electrode, wherein the second end portion of the
second roof layer and a first end portion of the third roof layer
are disposed between the first end portion of the second roof layer
and a second end portion of the third roof layer, and wherein the
first end portion of the third roof layer does not overlap, in the
first direction, any support member that is analogous to the first
support member or the second support member.
5. The method of claim 4, further comprising: forming a third
support member, which overlaps the second end portion of the third
roof layer in the first direction.
6. The method of claim 4, further comprising: providing a liquid
crystal material through a gap between the second roof layer and
the third roof layer to the second cavity and the third cavity; and
preventing providing any liquid crystal material through a gap
between the first roof layer and the second roof layer.
7. The method of claim 4, further comprising: providing an
alignment layer material through a gap between the second roof
layer and the third roof layer to the second cavity and the third
cavity; and preventing providing any alignment layer material
through a gap between the first roof layer and the second roof
layer.
8. The method of claim 1, further comprising: forming a step member
between the first support member and the first roof layer, wherein
a width of the step member in a second direction is larger than a
width of the first support member in the second direction.
9. The method of claim 1, further comprising: forming the first
support member, the first roof layer, and a step member between the
first support member and the first roof layer using a same
material.
10. The method of claim 1, further comprising: forming an
insulating layer between the first support member and the first
subpixel electrode, wherein the first support member overlaps the
first subpixel electrode in the first direction.
11. The method of claim 1, wherein the first support member does
not overlap the first subpixel electrode in the first direction.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a divisional application of U.S. patent
application Ser. No. 14/151,727 filed Jan. 9, 2014, which claims
priority to and the benefit of Korean Patent Application No.
10-2013-0063042 filed in the Korean Intellectual Property Office on
May 31, 2013, the entire contents of which are incorporated herein
by reference.
BACKGROUND
[0002] (a) Technical Field
[0003] The present invention relates to a display device and a
manufacturing method thereof.
[0004] (b) Description of the Related Art
[0005] A liquid crystal display typically includes two field
generating electrodes, such as a pixel electrode and a common
electrode, and a liquid crystal layer interposed therebetween. The
field generating electrodes may generate an electric field in the
liquid crystal layer to determine an orientation of liquid crystal
molecules of the liquid crystal layer for controlling transmission
of incident light, thereby displaying images.
[0006] A conventional liquid crystal display typically requires a
thin film transistor array panel and an opposite panel. The thin
film transistor array panel may include a gate line (configured for
transferring a gate signal), and a data line (configured for
transferring a data signal), a thin film transistor connected to
the gate line and the data line, and a pixel electrode connected to
the thin film transistor. The opposite panel may include a light
blocking member, a color filter, and a common electrode. In some
cases, the light blocking member, the color filter, and the common
electrode may be included in the thin film transistor array
panel.
[0007] Each of the thin film transistor array panel and the
opposite panel may require at least one substrate. The two
substrates may undesirably contribute to the weight, the
manufacturing cost, and/or the manufacturing time of the liquid
crystal display.
[0008] The above information disclosed in this Background section
is for enhancement of understanding of the background of the
invention. The Background section may contain information that does
not form the prior art that is already known in this country to a
person of ordinary skill in the art.
SUMMARY
[0009] Embodiments of the present invention may be related to a
display device that requires only one substrate. Advantageously,
the weight, the thickness, the cost, and/or the manufacturing time
associated the display device may be minimized.
[0010] Embodiments of the present invention may be related to a
method for manufacturing a display device. In the method,
obstruction against material injection may be avoided and/or
minimized. Advantageously, the manufacturing time and cost
associated with the display device may be minimized.
[0011] An embodiment of the present invention may be related to a
display device that may include a first subpixel electrode; a first
roof layer; a first liquid crystal layer disposed between the first
subpixel electrode and the first roof layer; and a first support
member overlapping a first end portion of the first roof layer in a
first direction and overlapping the first liquid crystal layer in a
second direction. The first direction may be substantially
perpendicular to a surface (e.g., a top surface) of the roof layer.
The second direction may be substantially perpendicular to the
first direction. The display device may further include a second
subpixel electrode immediately neighboring the first subpixel
electrode without any subpixel electrode being disposed between the
first subpixel electrode and the second subpixel electrode; a
second roof layer; a second liquid crystal layer disposed between
the second subpixel electrode and the second roof layer; and a
second support member overlapping a first end portion of the second
roof layer in the first direction and overlapping the second liquid
crystal layer in the second direction. The first end portion of the
first roof layer and the first end portion of the second roof layer
may be disposed between a second end portion of the first roof
layer and a second end portion of the second roof layer.
[0012] Support members that include the first support member and
the second support member may provide sufficient structural support
for other elements (such as roof layers) of the display device.
Therefore, the display device may require only one substrate.
[0013] The second end portion of the first roof layer may not
overlap, in the first direction, any support member that is
analogous to the first support member or the second support member.
The second end portion of the second roof layer may not overlap, in
the first direction, any support member that is analogous to the
first support member or the second support member.
[0014] The display device may further include a third subpixel
electrode, which may immediately neighbor the second subpixel
electrode without any subpixel electrode being disposed between the
second subpixel electrode and the third subpixel electrode. The
second subpixel electrode may be disposed between the first
subpixel electrode and the third subpixel electrode. The second
roof layer may overlap both the second subpixel electrode and the
third subpixel electrode. A center portion of the second roof layer
may be disposed between the first end portion of the second roof
layer and the second end portion of the second roof layer. The
center portion of the second roof layer may not overlap, in the
first direction, any support member that is analogous to the first
support member or the second support member.
[0015] The display device may further include a fourth subpixel
electrode, which may immediately neighbor the third subpixel
electrode without any subpixel electrode being disposed between the
third subpixel electrode and the fourth subpixel electrode. The
display device may further include a third roof layer, which may
overlap the fourth subpixel electrode in the first direction. The
third subpixel electrode may be disposed between the second
subpixel electrode and the fourth subpixel electrode. The second
end portion of the second roof layer and a first end portion of the
third roof layer may be disposed between the first end portion of
the second roof layer and a second end portion of the third roof
layer. The first end portion of the third roof layer may not
overlap, in the first direction, any support member that is
analogous to the first support member or the second support
member.
[0016] The display device may further include a third support
member, which may overlap the second end portion of the third roof
layer in the first direction.
[0017] A length of the first support member in the first direction
may be larger than a thickness of first subpixel electrode in the
first direction.
[0018] The display device may include a step member disposed
between the first support member and the first roof layer. A width
of the step member in the second direction may be larger than a
width of the first support member in the second direction.
[0019] The first support member, the first roof layer, and the step
member may be made of a same material.
[0020] The first support member may overlap the first subpixel
electrode in the first direction. The display device may include an
insulating layer disposed between the first support member and the
first subpixel electrode.
[0021] The second support member may not overlap the second
subpixel electrode in the first direction.
[0022] The first support member may not overlap the first subpixel
electrode in the first direction.
[0023] An embodiment of the present invention may be related to a
method for manufacturing a display device. The method may include
the following steps: forming a first subpixel electrode and a
second subpixel electrode, wherein the second subpixel electrode
may immediately neighbor the first subpixel electrode without any
subpixel electrode being disposed between the first subpixel
electrode and the second subpixel electrode; forming a first roof
layer and a second roof layer; forming a first support member and a
second support member, wherein the first support member may overlap
a first end portion of the first roof layer in a first direction,
wherein the second support member may overlap a first end portion
of the second roof layer in the first direction, and wherein the
first end portion of the first roof layer and the first end portion
of the second roof layer may be disposed between a second end
portion of the first roof layer and a second end portion of the
second roof layer; and forming a first cavity and a second cavity,
wherein a portion of the first cavity is positioned between the
first subpixel electrode and the first roof layer, and wherein a
first portion of the second cavity is positioned between the second
subpixel electrode and the second roof layer.
[0024] The second end portion of the first roof layer may not
overlap, in the first direction, any support member that is
analogous to the first support member or the second support member.
The second end portion of the second roof layer may not overlap, in
the first direction, any support member that is analogous to the
first support member or the second support member.
[0025] The method may further include the following step: forming a
third subpixel electrode, which may immediately neighbor the second
subpixel electrode without any subpixel electrode being disposed
between the second subpixel electrode and the third subpixel
electrode. The second subpixel electrode may be disposed between
the first subpixel electrode and the third subpixel electrode. The
second roof layer may overlap both the second subpixel electrode
and the third subpixel electrode. A second portion of the second
cavity may be positioned between the third subpixel electrode and
the second roof layer. A center portion of the second roof layer
may be disposed between the first end portion of the second roof
layer and the second end portion of the second roof layer. The
center portion of the second roof layer may not overlap, in the
first direction, any support member that is analogous to the first
support member or the second support member.
[0026] The method may further include the following steps: forming
a fourth subpixel electrode, which may immediately neighbor the
third subpixel electrode without any subpixel electrode being
disposed between the third subpixel electrode and the fourth
subpixel electrode; forming a third roof layer, which may overlap
the fourth subpixel electrode in the first direction; and forming a
third cavity. A portion of the third cavity may be positioned
between the fourth subpixel electrode and the third roof layer. The
third subpixel electrode may be disposed between the second
subpixel electrode and the fourth subpixel electrode. The second
end portion of the second roof layer and a first end portion of the
third roof layer may be disposed between the first end portion of
the second roof layer and a second end portion of the third roof
layer. The first end portion of the third roof layer may not
overlap, in the first direction, any support member that is
analogous to the first support member or the second support
member.
[0027] The method may further include the following step: forming a
third support member, which may overlap the second end portion of
the third roof layer in the first direction.
[0028] The method may include the following steps: providing a
liquid crystal material through a gap between the second roof layer
and the third roof layer to the second cavity and the third cavity;
and preventing providing any liquid crystal material through a gap
between the first roof layer and the second roof layer.
[0029] The method may include the following steps: providing an
alignment layer material through a gap between the second roof
layer and the third roof layer to the second cavity and the third
cavity; and preventing providing any alignment layer material
through a gap between the first roof layer and the second roof
layer.
[0030] The method may include the following step: forming a step
member between the first support member and the first roof layer. A
width of the step member in a second direction may be larger than a
width of the first support member in the second direction.
[0031] The method may include the following step: forming the first
support member, the first roof layer, and a step member between the
first support member and the first roof layer using a same
material.
[0032] The first support member may overlap the first subpixel
electrode in the first direction. The method may include the
following step: forming an insulating layer between the first
support member and the first subpixel electrode.
[0033] The first support member may not overlap the first subpixel
electrode in the first direction.
[0034] An embodiment of the present invention may be related to a
display device that may include the following elements: a substrate
including a plurality of pixel areas; a thin film transistor formed
on the substrate; a pixel electrode connected to the thin film
transistor and formed in the pixel area; a roof layer formed on the
pixel electrode to be spaced apart from the pixel electrode with a
microcavity; an injection hole formed at the roof layer so as to
expose a part of the microcavity; a support member adjacent to the
injection hole and formed in a column shape in the microcavity; a
liquid crystal layer filling the microcavity; and an encapsulation
layer formed on the roof layer so as to cover the injection hole to
seal the microcavity, in which support members are formed at
opposite edges of the two adjacent microcavities, respectively.
[0035] Injection holes may be formed at two opposite edges of each
microcavity. A support member may be formed at one of the two
opposite edges of each microcavity, and not be formed at the other
edge.
[0036] The microcavities may be disposed in a matrix form, and a
first valley may be disposed between the microcavities positioned
in two immediately neighboring rows.
[0037] Support members may be formed along two sides of a first
valley.
[0038] Support members may be formed along two sides of only one
first valley of two immediately neighboring first valleys.
[0039] The display device may further include a step member formed
between a support member and a roof layer associated with the
support member. The step member may be wider than the support
member.
[0040] The support member, the roof layer, and the step member may
be made of the same material.
[0041] A plurality of support members may be formed at one edge of
each microcavity.
[0042] The display device may further include an insulating layer
formed between a support member and a pixel electrode, wherein the
support member overlaps the pixel electrode.
[0043] A support member may not overlap a pixel electrode that is
associated with the support member.
[0044] An embodiment of the present invention may be related to a
method for manufacturing a display device. The method may include
the following steps: forming a thin film transistor on a substrate
including a plurality of pixel areas; forming a pixel electrode
connected to the thin film transistor in the pixel area; forming a
sacrificial layer on the pixel electrode; forming an opening by
removing a part of the sacrificial layer; forming a roof layer on
the sacrificial layer and forming a support member in the opening;
forming an injection hole by patterning the roof layer so that a
part of the sacrificial layer is exposed; forming a microcavity
between the pixel electrode and the roof layer by removing the
sacrificial layer; forming a liquid crystal layer in the
microcavity by injecting a liquid crystal material through the
injection hole; and forming an encapsulation layer on the roof
layer to seal the microcavity, in which the support members are
formed at opposite edges of the two adjacent microcavities,
respectively.
[0045] The support member may be adjacent to the injection hole and
may be formed in a column shape.
[0046] Injection holes may be formed at two opposite edges of each
microcavity. A support member may be formed at only one of the two
opposite edges of each microcavity, and no analogous support member
may be formed at the other edge. In the forming of the liquid
crystal layer, the liquid crystal material may be injected into the
injection hole positioned at the edge of the microcavity where no
support member is formed.
[0047] The microcavities may be disposed in a matrix form, and a
first valley may be disposed between microcavities positioned in
two immediately neighboring rows.
[0048] Support member may be formed along two sides of a first
valley.
[0049] Support member may be formed along two sides of only one
first valley of two immediately neighboring first valleys. In the
forming of the liquid crystal layer, the liquid crystal material
may be supplied to the first valley where no support member is
formed.
[0050] The pixel area may be disposed in a matrix form including a
plurality of pixel rows and a plurality of pixel columns. In the
forming of the opening, a sacrificial layer positioned between the
plurality of pixel columns may be removed together, and the roof
layer may be formed between the plurality of pixel columns to cover
a side of the microcavity.
[0051] In the forming of the opening, a groove portion may be
formed in the sacrificial layer by slit-exposing or
halftone-exposing the surroundings of the opening. In the forming
of the roof layer and the support member, a step member may be
formed in the groove portion.
[0052] The step member may be wider than the support member and may
be disposed between the support member and the roof layer.
[0053] The support member, the roof layer, and the step member may
be made of the same material during the same process.
BRIEF DESCRIPTION OF THE DRAWINGS
[0054] FIG. 1 is a plan view illustrating a display device
according to an embodiment of the present invention.
[0055] FIG. 2 is a plan view illustrating a display device
according to an embodiment of the present invention.
[0056] FIG. 3 is a plan view illustrating a pixel of a display
device according to an embodiment of the present invention.
[0057] FIG. 4 is a plan view illustrating a pixel of a display
device according to an embodiment of the present invention.
[0058] FIG. 5 is a cross-sectional view taken along line V-V
indicated in FIG. 1 according to an embodiment of the present
invention.
[0059] FIG. 6 is a cross-sectional view taken along line VI-VI
indicated in FIG. 1 according to an embodiment of the present
invention.
[0060] FIG. 7 is a cross-sectional view taken along line VII-VII
indicated in FIG. 1 according to an embodiment of the present
invention.
[0061] FIG. 8 is a plan view illustrating a pixel of a display
device according to an embodiment of the present invention.
[0062] FIG. 9 is a cross-sectional view taken along line IX-IX
indicated in FIG. 8 according to an embodiment of the present
invention.
[0063] FIGS. 10, 11, 12, 13 and 14 are process cross-sectional
views illustrating a method for manufacturing a display device
according to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0064] The present invention will be described more fully
hereinafter with reference to the accompanying drawings, in which
embodiments of the invention are shown. As those skilled in the art
would realize, the described embodiments may be modified in various
different ways, all without departing from the spirit or scope of
the present invention.
[0065] In the drawings, the thicknesses of layers, films, panels,
regions, etc., may be exaggerated for clarity. Like reference
numerals may designate like elements in the specification. If an
element such as a layer, film, region, or substrate is referred to
as being "on" another element, it can be directly on the other
element, or at least one intervening element may also be present.
In contrast, if an element is referred to as being "directly on"
another element, there are no intended intervening elements (except
one or more environmental elements, such as air) present.
[0066] Although the terms first, second, etc. may be used herein to
describe various signals, elements, components, regions, layers,
and/or sections, these signals, elements, components, regions,
layers, and/or sections should not be limited by these terms. These
terms may be used to distinguish one signal, element, component,
region, layer, or section from another signal, region, layer, or
section. Thus, a first signal, element, component, region, layer,
or section discussed below may be termed a second signal, element,
component, region, layer, or section without departing from the
teachings of the present invention. The description of an element
as a "first" element may not require or imply the presence of a
second element or other elements. The terms first, second, etc. may
also be used herein to differentiate different categories of
elements. For conciseness, the terms first, second, etc. may
represent first-type (or first-category), second-type (or
second-category), etc., respectively.
[0067] In the description, the term "connect" may mean
"electrically connect"; the term "insulate" may mean "electrically
insulate".
[0068] FIG. 1 is a plan view illustrating a display device
according to an embodiment of the present invention. FIG. 2 is a
plan view illustrating a display device according to an embodiment
of the present invention. For clarity of illustration and
discussion, only some constituent elements are illustrated in FIGS.
1 and 2. In the display device illustrate in FIG. 1, formation
positions of support members may be based on a plurality of pixel
areas. In the display device illustrated in FIG. 2, formation
positions of support members may be based on a plurality of
microcavities.
[0069] A display device according to an embodiment of the present
invention includes a substrate 110 and a roof layer 360 formed on
the substrate 110. The substrate may be made of at least one of
glass and plastic.
[0070] The substrate 110 includes a plurality of pixel areas PX.
The plurality of pixel areas PX may form a matrix that includes a
plurality of pixel rows and a plurality of pixel columns. Each
pixel area PX may include a first subpixel area PXa and a second
subpixel area PXb. The first subpixel area PXa and the second
subpixel area PXb may be substantially vertically disposed and/or
may be aligned in a pixel column direction.
[0071] A first valley V1 is positioned between the first subpixel
area PXa and the second subpixel area PXb in a pixel row direction,
and a second valley V2 is positioned between two immediately
neighboring pixel columns.
[0072] Portions of the roof layer 360 may be formed along the
plurality of pixel rows. In an embodiment, the first valley V1 may
be positioned between two immediately neighboring portions of the
roof layer 360 and thus may enable access through at least an
injection hole 307 to at least a microcavity 305 covered by the
roof layer 360 during manufacturing of the display device.
[0073] Each of the first subpixel area PXa and the second subpixel
area PXb may be associated with an injection hole 307, which may be
an opening that allows access to a microcavity 305. An injection
hole 307 may correspond to a lower side of the first subpixel area
PXa, and an injection hole 307 may correspond to an upper side of
the second subpixel area PXb. The two injection holes 307 may face
each other.
[0074] A support member 365 may be adjacent to the injection hole
307 and may be below the roof layer 360. According to an embodiment
of the present invention, the support member 365 may support the
roof layer 360. Advantageously, potential sagging of the roof layer
360 around the injection hole 307 may be prevented.
[0075] Two support members 365 may be formed at opposite edges of
two opposite microcavities 305, respectively. The plurality of
microcavities 305 is disposed in a matrix form, and each
microcavity may correspond to a subpixel area. The microcavity 305
may have a substantially quadrangular shape in a plan view of the
display device. A first injection hole 307 for accessing a first
microcavity 305 that corresponds to a first subpixel area PXa may
face a second injection hole 307 for accessing a second microcavity
305 that corresponds to a second subpixel area PXb that faces the
first subpixel area PXa. In an embodiment, a first support member
365 may be disposed adjacent to the first injection hole 307 for
reinforcing the first microcavity 305, and a second support member
365 may be disposed adjacent to the second injection hole 307 for
reinforcing the second microcavity 305. The first injection hole
307 and the second injection hole 307 may be positioned between the
first support member 365 and the second support member 365.
[0076] A first microcavity 305 may correspond to a first pixel area
PXa, and a second microcavity 305 may correspond to a second pixel
area PXb. A first edge of the first microcavity 305 and a first
edge of the second microcavity 305 may be positioned between a
second edge of the first microcavity 305 and a second edge of the
second microcavity 305.
[0077] In an embodiment, a first injection hole 307 and a first
support member 365 may be formed at the first edge of the first
microcavity 305, and a second injection hole 307 and a second
support member may be formed at the first edge of the second
microcavity 305.
[0078] In an embodiment, no support member 365 is formed at the
second edge of the first microcavity 305 or at the second edge of
the second microcavity 305.
[0079] In an embodiment, a first injection hole 307 and a first
support member 365 may be formed at the first edge of the first
microcavity 305, and a second injection hole 307 and a second
support member may be formed at the second edge of the first
microcavity 305.
[0080] In an embodiment, no support member 365 is formed at the
first edge of the second microcavity 305 or at the second edge of
the second microcavity 305.
[0081] In an embodiment, a first injection hole 307 and a first
support member 365 may be formed at the second edge of the first
microcavity 305, and a second injection hole 307 and a second
support member may be formed at the second edge of the second
microcavity 305.
[0082] In an embodiment, no support member 365 is formed at the
first edge of the first microcavity 305 or at the first edge of the
second microcavity 305.
[0083] In an embodiment, an upper edge and a lower edge of a
microcavity 305 may be substantially parallel to each other, and at
least an injection hole 307 and at least a support member 365
neighboring the injection hole 307 may be formed at each of an
upper side and a lower side of the microcavity 305.
[0084] In an embodiment, support members 365 may be formed at the
lower edges of the microcavities 305 in the odd numbered rows, but
no support members 365 are formed at the upper edges of the
microcavities 305 in the odd numbered rows.
[0085] In an embodiment, support members 365 may be formed at the
upper edge of the microcavity 305 in the even numbered rows, but no
support members 365 are formed at the lower edges of the
microcavity 305 in the even numbered rows.
[0086] A first valley V1 is positioned between two immediately
neighboring microcavities 305 that positioned in different rows. In
an embodiment, support members 365 may be adjacent to and
correspond to each of two sides of a first first valley V1, and no
support member 365 may be adjacent to or correspond to the sides of
a second first valley V1 that immediately neighbors the first first
valley V1.
[0087] In an embodiment, one microcavity 305 may be formed in each
of a first subpixel area PXa and a second subpixel area PXb. In an
embodiment, only one microcavity 305 may be formed in each pixel
area PX.
[0088] FIG. 3 is a plan view illustrating a pixel of a display
device according to an embodiment of the present invention. FIG. 4
is a plan view illustrating a pixel of a display device according
to an embodiment of the present invention. FIG. 5 is a
cross-sectional view taken along line V-V indicated in FIG. 1
according to an embodiment of the present invention. FIG. 6 is a
cross-sectional view taken along line VI-VI indicated in FIG. 1
according to an embodiment of the present invention. FIG. 7 is a
cross-sectional view taken along line VII-VII indicated in FIG. 1
according to an embodiment of the present invention
[0089] FIGS. 3 and 5 illustrate a pixel in which support members
are formed at edges of microcavities. FIGS. 4 and 6 illustrate a
pixel in which no support members are formed at edges of
microcavities.
[0090] Referring to FIGS. 1 to 7, a pixel may be associated with a
plurality of gate conductors, including a gate line 121, a
step-down gate line 123, and a storage electrode line 131, which
may be formed on the substrate 110.
[0091] The gate line 121 and the set-down gate line 123 may mainly
extend in a horizontal direction (or pixel row direction parallel
to the first valley V1) and may transfer gate signals. The gate
conductors may include a first gate electrode 124h and a second
gate electrode 124I that protrude substantially upward and
downward, respectively, from the gate line 121. The gate conductors
may include a third gate electrode 124c that protrudes upward from
the step-down gate line 123. The first gate electrode 124h and the
second gate electrode 124l may be connected to and substantially
aligned with each other in the pixel column direction and may form
an enlarged portion of the gate line 121. The gate electrodes 124h,
124l, and 124c may have one or more other protrusion
configurations.
[0092] Each storage electrode line 131 mainly extends in a
horizontal direction (e.g., the pixel row direction) to transfer
predetermined voltage such as common voltage Vcom. The storage
electrode line 131 includes storage electrodes 129 that protrude
upward and downward, a pair of vertical portions 134 that extends
toward the gate line 121 and extends substantially vertical to the
gate line 121, and a horizontal portion 127 that connects ends of
the vertical portions 134. The horizontal portion 127 includes a
capacitor electrode 137 that expands toward the gate line 121.
[0093] A gate insulating layer 140 is formed on (and may cover) the
gate conductors 121, 123, 124h, 124l, 124c, and 131. The gate
insulating layer 140 may be made of an inorganic insulating
material, such as at least one of silicon nitride (SiNx) and
silicon oxide (SiOx). The gate insulating layer 140 may have a
single layer structure or a multiple layer structure.
[0094] A first semiconductor 154h, a second semiconductor 154l, and
a third semiconductor 154c are formed on the gate insulating layer
140. The first semiconductor 154h may be positioned on the first
gate electrode 124h, the second semiconductor 154l may be
positioned on the second gate electrode 124I, and the third
semiconductor 154c may be positioned on the third gate electrode
124c. The first semiconductor 154h and the second semiconductor
154l may be connected to each other, and the second semiconductor
154l and the third semiconductor 154c may be connected to each
other. The first semiconductor 154h may overlap an extended portion
of the data line 171. The semiconductors 154h, 154l, and 154c may
be made of one or more of amorphous silicon, polycrystalline
silicon, metal oxide, etc.
[0095] Ohmic contacts (not illustrated) may be formed on the
semiconductors 154h, 154l, and 154c, respectively. The ohmic
contacts may be made of silicide or a material (such as n+
hydrogenated amorphous silicon) in which an n-type impurity is
doped at high concentration.
[0096] A pixel may be associated with a plurality of data
conductors, including a data line 171, a first source electrode
173h, a second source electrode 173l, a third source electrode
173c, a first drain electrode 175h, a second drain electrode 175l,
and a third drain electrode 175c. Some of the data conductors may
be formed on the semiconductors 154h, 154l, and 154c.
[0097] The data line 171 may transfer a data signal. The data line
171 may mainly extend in a vertical direction (e.g., the pixel
column direction) and may cross the gate lines 121 and the set-down
gate lines 123. The data line 171 may include (or may be connected
to) a first source electrode 173h and a second source electrode
173l, which correspond to (and/or extend toward) the first gate
electrode 124h and the second gate electrode 124l, respectively,
and are connected with each other.
[0098] Each of a first drain electrode 175h, a second drain
electrode 175l, and a third drain electrode 175c may include a
relatively wide portion and a relatively narrow rod-shaped portion.
The rod-shaped portions of the first drain electrode 175h and the
second drain electrode 175l are partially surrounded by the first
source electrode 173h and the second source electrode 173l,
respectively. The relatively wide portion of the second drain
electrode 175l is connected to a third source electrode 173c, which
has a `U`-lettered shape. The relatively wide portion 177c of the
third drain electrode 175c overlaps the capacitor electrode 137 to
form a set-down capacitor Cstd, and the rod-shaped portion of the
third drain electrode 175c is partially surrounded by the third
source electrode 173c.
[0099] The first gate electrode 124h, the first source electrode
173h, and the first drain electrode 175h form a first thin film
transistor Qh together with the first semiconductor 154h. The
second gate electrode 124I, the second source electrode 173I and
the second drain electrode 175I form a second thin film transistor
Ql together with the second semiconductor 154I. The third gate
electrode 124c, the third source electrode 173c and the third drain
electrode 175c form the third thin film transistor Qc together with
the third semiconductor 154c.
[0100] The first semiconductor 154h, the second semiconductor 154I,
and the third semiconductor 154c are connected to each other. One
or more of the semiconductors 154h, 154I, and 154c may have
substantially the same planar shape as one or more of the data
conductors 173h, 173l, 173c, 175h, 175l, and 175c and one or more
of the associated ohmic contacts, except for one or more channel
regions between one or more of the source electrodes 173h, 173l,
and 173c and one or more of the drain electrodes 175h, 175l, and
175c.
[0101] In the first semiconductor 154h, an exposed portion that is
not covered by the first source electrode 173h and the first drain
electrode 175h is disposed between the first source electrode 173h
and the first drain electrode 175h in a plan view of the display
device. In the second semiconductor 154l, an exposed portion that
is not covered by the second source electrode 173l and the second
drain electrode 175l is disposed between the second source
electrode 173l and the second drain electrode 175l in the plan view
of the display device. In the third semiconductor 154c, an exposed
portion that is not covered by the third source electrode 173c and
the third drain electrode 175c is disposed between the third source
electrode 173c and the third drain electrode 175c.
[0102] A passivation layer 180 is formed on the data conductors
171, 173h, 173l, 173c, 175h, 175l, and 175c and portions of the
semiconductors 154h, 154l, and 154c exposed between the respective
source electrodes 173h, 173l, and 173c and the respective drain
electrodes 175h, 175l, and 175c. The passivation layer 180 may be
made of an organic insulating material or an inorganic insulating
material. The passivation layer 18 may have a single layer
structure or a multiple layer structure.
[0103] A color filter 230 in each pixel area PX is formed on the
passivation layer 180. The color filter 230 may display one of
primary colors and/or may display white. In an embodiment, the
primary colors may be three primary colors of red, green and blue.
In an embodiment the primary colors may include cyan, magenta, and
yellow. In an embodiment, a color filter 230 may extend in a column
direction along a space between immediately adjacent data lines
171.
[0104] A light blocking member 220 is formed in a region between
immediately adjacent color filters 230 and/or between separated
portions of color filters. The light blocking member 220 overlaps
at least a boundary of the pixel area PX, the thin film
transistors, and the support member 365 to prevent light leakage. A
color filter 230 (or a portion of a color filter 230) is formed in
each of the first subpixel area PXa and the second subpixel area
PXb. A portion of the light blocking member 220 may be formed
between the first subpixel area PXa and the second subpixel area
PXb to cover the thin film transistors.
[0105] The light blocking member 220 includes a horizontal light
blocking member 220a that extends along the gate line 121 and the
step-down gate line 123 and covers the first thin film transistor
Qh, the second thin film transistor Ql, and the third thin film
transistor Qc. The light blocking member 220 further includes a
vertical light blocking member 220b that extends along the data
line 171. The horizontal light blocking member 220a may overlap the
first valley V1, and the vertical light blocking member 220b may
overlap the second valley V2. The color filter 230 and the light
blocking member 220 may directly contact each other in a same layer
of the display device and may both directly contact the passivation
layer 180.
[0106] A first insulating layer 240 may be formed on the color
filter 230 and the light blocking member 220. The first insulating
layer 240 may be made of an inorganic insulating material, such as
at least one of silicon nitride (SiNx) and silicon oxide (SiOx).
The first insulating layer 240 serves to protect the color filter
230 (which may be made of an organic material) and the light
blocking member 220. In an embodiment, the first insulating layer
240 may be omitted.
[0107] In the first insulating layer 240, the light blocking member
220, and the passivation layer 180, a first contact hole 185h and a
second contact hole 185l are formed.
[0108] A pixel electrode 191 is formed on the first insulating
layer 240. The pixel electrode 191 may be made of a transparent
metal material, such as at least one of indium tin oxide (ITO) and
indium zinc oxide (IZO). The pixel electrode 191 may be connected
to drain electrodes through the contact holes 185h and 185l.
[0109] The pixel electrode 191 includes a first subpixel electrode
191h and a second subpixel electrode 191l, which are separated from
each other with the gate line 121 and the step-down gate line 123
being disposed substantially between the subpixel electrodes 191h
and 191l. The subpixel electrodes may be substantially aligned with
each other in a column direction. The first subpixel electrode 191h
and the second subpixel electrode 191l may be separated from each
other with the first valley V1 being disposed therebetween in a
plan view of the display device. The first subpixel electrode 191h
is positioned in the first subpixel area PXa, and the second
subpixel electrode 191l is positioned in the second subpixel area
PXb.
[0110] The first subpixel electrode 191h and the second subpixel
electrode 191l are connected to the first drain electrode 175h and
the second drain electrode 175l through the first contact hole 185h
and the second contact hole 185l, respectively. Accordingly, when
the first thin film transistor Qh and the second thin film
transistor Ql are turned on, the first subpixel electrode 191h and
the second subpixel electrode 191l receive data voltages from the
first drain electrode 175h and the second drain electrode 175l.
[0111] An overall shape of the first subpixel electrode 192h and
the second subpixel electrode 191l may be substantially a
quadrangle. The first subpixel electrode 191h and the second
subpixel electrode 191l include cross stems. The cross stems
include horizontal stems 193h and 193l and vertical stems 192h and
192l that cross the horizontal stems 193h and 193l, respectively.
The first subpixel electrode 191h and the second subpixel electrode
191l may further include a plurality of minute branches 194h and
1941 and may further include protrusions 197h and 1971 protruding
upward or downward from edge sides of the subpixel electrodes 191h
and 191l, respectively.
[0112] Each of the subpixel electrodes 191h and 191l of the pixel
electrode 191 is divided into four sub-regions by an associated one
of the horizontal stems 193h and 193l and an associated one of the
vertical stems 192h and 192l. The minute branches 194h and 1941
obliquely extend from the horizontal stems 193h and 193l and the
vertical stems 192h and 192l, extending at an angle of
approximately 45 degrees or 135 degrees with respect to the gate
line 121 or the horizontal stems 193h and 193l. In an embodiment,
directions in which the minute branches 194h and 1941 of the two
adjacent sub-regions extend may be perpendicular to each other.
[0113] In an embodiment, the first subpixel electrode 191h may
include an outer stem that surrounds at least some elements of the
first subpixel electrode 191h. The second subpixel electrode 191l
may include horizontal portions positioned at an upper end and a
lower end of the second subpixel electrode 191l. The pixel
electrode 191 may include left and right vertical portions 198
positioned at the left and the right of the first subpixel
electrode 191h. The left and right vertical portions 198 may
prevent capacitive coupling (or coupling) between the data line 171
and the first subpixel electrode 191h.
[0114] The layout form of the pixel area, the structure of the thin
film transistor, and the shape of the pixel electrode described
above are examples and may be modified in various embodiments.
[0115] A second insulating layer 250 may be formed on the pixel
electrode 191. The second insulating layer 250 may be made of an
inorganic insulating material, such as at least one of silicon
nitride (SiNx) and silicon oxide (SiOx). The second insulating
layer 250 serves to protect the pixel electrode 191. In an
embodiment, the second insulating layer 250 may be omitted.
[0116] A common electrode 270 may overlap the pixel electrode 191
and may be spaced from the pixel electrode 191 at a predetermined
distance. A microcavity 305 is formed between the pixel electrode
191 and the common electrode 270. The microcavity 305 may be
substantially surrounded by at least one of the pixel electrode 191
and the common electrode 270. A width and an area of the
microcavity 305 may be configured according to a size and
resolution of the display device.
[0117] The second insulating layer 250 may prevent the common
electrode 270 and the pixel electrode 191 from contacting each
other and/or from being short-circuited.
[0118] In an embodiment, the common electrode 270 may be formed
directly on the second insulating layer 250. No microcavity 305 may
be formed between the pixel electrode 191 and common electrode 270.
The common electrode 270 may be positioned between pixel electrode
191 and a microcavity 305 and/or may be positioned between the
second insulating layer 250 and a microcavity 305.
[0119] The common electrode 270 may be made of a transparent metal
material, such as at least one of indium tin oxide (ITO) and indium
zinc oxide (IZO). A predetermined voltage may be applied to the
common electrode 270, and an electric field may be generated
between the pixel electrode 191 and the common electrode 270.
[0120] A first alignment layer 11 may overlap the pixel electrode
191. The first alignment layer 11 may also be formed directly on a
portion of the second insulating layer 250 such that the portion of
the second insulating layer 250 is disposed between the first
alignment layer 11 and the pixel electrode 191.
[0121] A second alignment layer 21 is formed on the common
electrode 270. The second alignment layer 21 is disposed between
the common electrode 270 the first alignment layer 11.
[0122] The first alignment layer 11 and the second alignment layer
21 may be vertical alignment layers and may be made of alignment
materials, such as at least one of polyamic acid, polysiloxane, and
polyimide. The alignment layers 11 and 21 may be connected to each
other at an edge of the pixel area PX.
[0123] A liquid crystal layer that includes liquid crystal
molecules 310 is formed in the microcavity 305 and is positioned
between the pixel electrode 191 and the common electrode 270. The
liquid crystal molecules 310 may have negative dielectric
anisotropy and may be oriented in a vertical direction that is
substantially perpendicular to the substrate 110 (i.e., in vertical
alignment) when no electric field is applied to the pixel electrode
191.
[0124] The first subpixel electrode 191h and the second subpixel
electrode 191l to which the data voltage is applied may generate an
electric field together with a common electrode 270 to determine
directions of the liquid crystal molecules 310. The luminance of
light that is transmitted through the liquid crystal layer may be
substantially determined by the directions (or orientations) of the
liquid crystal molecules 310.
[0125] A third insulating layer 350 may be formed on the common
electrode 270. The third insulating layer 350 may be made of an
inorganic insulating material, such as at least one of silicon
nitride (SiNx) and silicon oxide (SiOx). In an embodiment, the
third insulating layer 350 may be omitted.
[0126] A roof layer 360 is formed on the third insulating layer
350. The roof layer 360 may be made of an organic material. The
microcavity 305 is formed below the roof layer 360, and the roof
layer 360 is hardened by a curing process to maintain a shape of
the microcavity 305. The microcavity 305 may be positioned between
the roof layer 360 and the pixel electrode 191.
[0127] The roof layer 360 is formed in each pixel area PX and the
second valley V2 along a pixel row, and is not formed in the first
valley V1. That is, the roof layer 360 is not formed between the
first subpixel area PXa and the second subpixel area PXb. The
microcavity 305 is formed below each roof layer 360 in each of the
first subpixel area PXa and the second subpixel area PXb. In the
second valley V2, a portion of the roof layer 360 is disposed
between two portions of the microcavity 305. A thickness of the
portion of the roof layer 360 positioned at the second valley V2
may be larger than a thickness of other portions of the roof layer
360 positioned in each of the first subpixel area PXa and the
second subpixel area PXb. An upper surface and sides of the
microcavity 305 may be covered by the roof layer 360.
[0128] An injection hole 307 for exposing a part of (and/or for
access to) the microcavity 305 is formed in the roof layer 360.
Injection holes 307 may face each other at edges of the first
subpixel area PXa and the second subpixel area PXb. For example, a
first injection hole 307 may correspond to a lower side of the
first subpixel area PXa to allow access to a first microcavity 305
that overlaps the first subpixel electrode 191h, and a second
injection hole 307 may correspond to an upper side of the second
subpixel area PXb to allow access to a second microcavity 305 that
overlaps the second pixel electrode 191l. The first injection hole
307 may be positioned at a first edge of the first microcavity 305.
The second injection hole may be positioned at a first edge of the
second microcavity 305. The first edge of the first microcavity 305
and the first edge of the second microcavity 305 may be disposed
between a second edge of the first microcavity 305 and a second
edge of the second microcavity 305.
[0129] Since the microcavity 305 is exposed by the injection hole
307, an aligning agent and/or or a liquid crystal material may be
injected into the microcavity 305 through the injection hole
307.
[0130] A support member 365 may be disposed adjacent to the
injection hole 307, may have a column shape, and may be disposed at
an edge of a microcavity 305. As illustrated in FIGS. 3 and 5,
support members 365 are formed at immediately neighboring edges of
two immediately neighboring microcavities 305.
[0131] Two injection holes 307 may allow access to a same
microcavity 305. For example, a first injection hole 307 may be
positioned at a first edge (e.g., an upper edge) of a microcavity
305, and a second injection hole may be positioned at a second edge
(e.g., a lower edge) of the same microcavity 305. One or more
support members 365 may be formed at only one of the first
injection hole 307 and the second injection hole 307, and no
support member 365 may be formed at the other one of the first
injection hole 307 and the second injection hole 307. For example,
a support member 365 may be formed to be adjacent to the first
injection hole 307 positioned at the upper edge of a microcavity
305, and no support member 365 corresponds to the second injection
hole 307 positioned at the lower edge of the microcavity 305.
[0132] As illustrated in FIGS. 1, 3, and 5, support members 365 are
adjacent to (and/or correspond to) two sides of the odd numbered
first valleys V1. As illustrated in FIGS. 1, 4, and 6, no support
members 365 are adjacent to (or correspond to) sides of the even
numbered first valleys V1. In an embodiment, support members 365
may be adjacent to two sides of the even numbered first valleys V1,
and no support members 365 may be adjacent to sides of the odd
numbered first valleys V1.
[0133] The first alignment layer 11 and the second alignment layer
21 may be formed by injecting an aligning agent (or an alignment
material). Solids of the aligning agent may concentrate near
supporting member 365 during a drying process. In an embodiment,
since the support members 365 are positioned at an edge of a
microcavity 305, the concentrated solids of the aligning agent may
not substantially block light that is transmitted through the
liquid crystal layer. Therefore, the concentrated solids of the
alignment agent may not significant influence the image display
quality of the display device. In an embodiment, the light blocking
member 220 may overlap support members 365 and may substantially
overlap concentrated solids of the aligning agent, such that
influence of the concentrated solids of the aligning agent on image
display quality may be minimized. Since supporting members are
formed at an edge of a microcavity 305, an area of a pixel that is
overlapped by the light blocking member 220 may be minimized.
Advantageously, an aperture ratio may be maximized.
[0134] The concentrated solids of the aligning agent might exert a
force on the roof layer and might potentially cause deformation of
the roof layer 360 if the roof layer 360 were not properly
supported. In an embodiment, since a support member 365 is adjacent
to the concentrated solids of the aligning agent, the support
member 365 may properly support the roof layer 360. Advantageously,
deformation of the roof layer 360 may be prevented.
[0135] A support member 365 is connected to the roof layer 360 and
may be made of the same material as the roof layer 360. A portion
of the third insulating layer 350 and/or a portion of the common
electrode 270 may be positioned between the support member 365 and
at least one of the second insulation layer 250 and a pixel
electrode (e.g., 191h or 191l). The support member 365 may overlap
the pixel electrode 191, which overlaps and is insulated from the
common electrode 270.
[0136] In an embodiment, a support member 365 may be made of a
material that is different from the material of the roof layer 360.
In an embodiment, a support member 365 may be formed directly on
(and may directly contact) one or more of the pixel electrode 191,
the second insulating layer 250, and the first insulating layer
240.
[0137] A plurality of support members 365 may be formed at one edge
of a microcavity 305. For example, two or more support members 365
may be formed at an edge of each microcavity 305. In an embodiment,
a size of a microcavity 305 and/or a size of a support member 365
are considered in determining the number of support members 365
formed in each microcavity 305.
[0138] The shape of a support member 365 may be a quadrangle in a
plan view of a pixel. In an embodiment, one or more support members
365 may be formed in one or more of various shapes, such as a
circle and a triangle.
[0139] A step member 362 may be formed between a support member 365
and a roof layer 360. The step member 362 may have a larger width
than the support member 365 in a plan view of the display device.
The step member 362 may be made of the same material as the support
member 365. In an embodiment, all of the step member 362, the
support member 365, and the roof layer 360 may be made of the same
material.
[0140] A fourth insulating layer 370 may be further formed on the
roof layer 360. The fourth insulating layer 370 may be made of an
inorganic insulating material, such as at least one of silicon
nitride (SiNx) and silicon oxide (SiOx). The fourth insulating
layer 370 may be formed to cover the top and the side of the roof
layer 360. The fourth insulating layer 370 serves to protect the
roof layer 360 (which may be made of an organic material). In an
embodiment, the fourth insulating layer 370 may be omitted.
[0141] An encapsulation layer 390 may be formed on the fourth
insulating layer 370. The encapsulation layer 390 is formed to
cover the injection hole 307, where a part of the microcavity 305
is exposed. The encapsulation layer 390 may seal the microcavity
305 so that the liquid crystal molecules 310 in the microcavity 305
are retained inside microcavity 305 without undesirable leakage. In
an embodiment, the encapsulation layer 390 may directly contact
some of the liquid crystal molecules 310, and the encapsulation
layer 390 may be made of a material that does not substantially
(chemically) react with liquid crystal molecules 310. For example,
the encapsulation layer 390 may be made of parylene and/or one or
more materials that have analogous properties.
[0142] The encapsulation layer 390 may have a multilayer, such as a
double layer structure of a triple layer structure. The double
layer structure may include two layers made of different materials.
The triple layer structure may include three layers, wherein
materials of adjacent layers are different from each other. For
example, the encapsulation layer 390 may include a layer made of an
organic insulating material and may include a layer made of an
inorganic insulating material.
[0143] Although not illustrated, polarizers may be further formed
on the upper and lower sides of the display device. The polarizers
may include a first polarizer and a second polarizer. The first
polarizer may be attached onto the lower side of the substrate 110,
and the second polarizer may be attached onto the encapsulation
layer 390.
[0144] FIG. 8 is a plan view illustrating a pixel of a display
device according to an embodiment of the present invention. FIG. 9
is a cross-sectional view taken along line IX-IX indicated in FIG.
8 according to an embodiment of the present invention.
[0145] Elements and features of the display device illustrated in
FIGS. 8 and 9 may be identical to or analogous to elements and
features of the display device illustrated in FIGS. 1 to 7.
Description of identical or analogous elements and/or features may
be omitted. In the display device illustrated in FIGS. 8 and 9,
support members may not overlap any pixel electrode in a direction
perpendicular to a top surface of a pixel electrode.
[0146] Referring to FIGS. 8 and 9, in a display device according to
an exemplary embodiment of the present invention, a thin film
transistor and a pixel electrode 191 connected to the thin film
transistor are formed on a substrate 110. A roof layer 360 overlaps
the pixel electrode 191. A microcavity 305 is disposed between the
roof layer 360 and the pixel electrode 191. A support member 365 is
formed in the microcavity 305 and is adjacent to an injection hole
307. A liquid crystal layer that includes liquid crystal molecules
310 is formed in the microcavity 305. An encapsulation layer 390 is
formed on the roof layer 360 to seal the microcavity 305.
[0147] The support member 365 is connected to the roof layer 360
and may be made of the same material as the roof layer 360. A
portion of a third insulating layer 350 and a portion of a common
electrode 270 may be positioned between the support member 365 and
at least one of a first insulating layer 240 and a light blocking
member 220. The portion of the common electrode 270 may directly
contact the first insulating layer 240 and/or the light blocking
member 220. The support member 365 may not overlap the pixel
electrode 191 in a direction perpendicular to a top surface of the
pixel electrode 191. Accordingly, even though no additional
insulating layer is formed between the pixel electrode 191 and the
common electrode 270, there may be no short-circuit between the
common electrode 270 and the pixel electrode 191.
[0148] FIGS. 10 to 14 are process cross-sectional views
illustrating a method for manufacturing a display device according
to an embodiment of the present invention.
[0149] A gate line 121 and a step-down gate line 123 (both
extending in one direction) are formed on a substrate 110, which
may be made of glass or plastic. Substantially simultaneously, a
first gate electrode 124h, a second gate electrode 124l, and a
third gate electrode 124c, which protrude from the gate line 121,
are formed.
[0150] Substantially simultaneously, a storage electrode line 131
may be formed. The storage electrode line 131 may be spaced apart
from the gate line 121, the step-down gate line 123, and the gate
electrodes 124h, 124l, and 124c.
[0151] Subsequently, a gate insulating layer 140 is formed on the
entire surface of a substrate 110 and may cover the gate line 121,
the step-down gate line 123, the gate electrodes 124h, 124l, and
124c, and the storage electrode 131. The gate insulating layer 140
may be formed of an inorganic insulating material, such as silicon
oxide or silicon nitride. The gate insulating layer 140 may have a
single layer structure or a multiple layer structure.
[0152] Subsequently, a first semiconductor 154h, a second
semiconductor 154l, and a third semiconductor 154c are formed by
depositing a semiconductor material (such as at least one of
amorphous silicon, polycrystalline silicon, and metal oxide) on the
gate insulating layer 140 and then patterning the deposited
semiconductor material. The first semiconductor 154h may be
positioned on the first gate electrode 124h, the second
semiconductor 154l may be positioned on the second gate electrode
124l, and the third semiconductor 154c may be positioned on the
third gate electrode 124c.
[0153] Subsequently, a data line 171 (extending in the other
direction) is formed by depositing a metal material and then
patterning the deposited metal material. The metal material may
have a single layer structure or a multiple layer structure.
[0154] Substantially simultaneously, a first source electrode 173h
(which protrudes from the data line 171 above the first gate
electrode 124h) and a first drain electrode 175h (which is spaced
apart from the first source electrode 173h) are formed.
Substantially simultaneously, a second source electrode 173l (which
is connected to the first source electrode 173h) and a second drain
electrode 175l (which is spaced apart from the second source
electrode 173l) are formed. Substantially simultaneously, a third
source electrode 173c (which extends from the second drain
electrode 175l) and a third drain electrode 175c (which is spaced
apart from the third source electrode 173c) are formed.
[0155] The semiconductors 154h, 154l, and 154c, the data line 171,
the source electrodes 173h, 173l, and 173c, and the drain
electrodes 175h, 175l, and 175c may be formed by sequentially
depositing a semiconductor material and a metal material and then
patterning the semiconductor material and the metal material in a
same patterning process. In an embodiment, the first semiconductor
154h may overlap a portion of the data line 171.
[0156] The gate electrodes 124h, 124l, and 124c, the source
electrodes 173h, 173l, and 173c, and the drain electrodes 175h,
175l, and 175c form thin film transistors (TFTs) Qh, Ql, and Qc
together with the semiconductors 154h, 154l, and 154c,
respectively.
[0157] Subsequently, a passivation layer 180 is formed on the data
line 171, the source electrodes 173h, 173l, and 173c, the drain
electrodes 175h, 175l, and 175c, and the semiconductors 154h, 154l,
and 154c exposed between the respective source electrodes 173h,
173l, and 173c and the respective drain electrodes 175h, 175l, and
175c. The passivation layer 180 may be made of an organic
insulating material and/or an inorganic insulating material. The
passivation layer 180 may have a single layer structure or a
multiple layer structure.
[0158] Subsequently, a color filter 230 is formed in each pixel
area PX on the passivation layer 180. A color filter 230 or a
portion of a color filter 230 is formed in each of the first
subpixel area PXa and the second subpixel area PXb. No color filter
may be formed at the first valley V1. Color filters 230 having the
same color may be formed in a column direction in columns of the
plurality of pixel areas PX. For forming color filters 230 having
three colors, a first colored color filter 230 may be first formed
and then a second colored color filter 230 may be formed by
shifting a mask. Subsequently, the second colored color filter 230
may be formed and then a third colored color filter may be formed
by shifting a mask.
[0159] Subsequently, a light blocking member 220 is formed on a
boundary of each pixel area PX and may be formed on the passivation
layer 180 and the thin film transistors. The light blocking member
220 may also be formed at the first valley V1 positioned between
the first subpixel area PXa and the second subpixel area PXb.
[0160] The light blocking member 220 may be formed at one or more
edges of each pixel area PX. The light blocking member 220 may
overlap a support member 365 that is subsequently formed.
[0161] In an embodiment, the light blocking member 220 is formed
after the color filters 230 have been formed. In an embodiment, the
light blocking member 220 may be formed before formation of the
color filters 230.
[0162] Subsequently, a first insulating layer 240, which may be
made of an inorganic insulating material such as at least one of
silicon nitride (SiNx) and silicon oxide (SiOx), is formed on the
color filter 230 and the light blocking member 220.
[0163] Subsequently, a first contact hole 185h is formed by etching
the passivation layer 180, the light blocking member 220, and the
first insulating layer 240 so as to expose a part of the first
drain electrode 175h, and a second contact hole 185l is formed so
as to expose a part of the second drain electrode 175l.
[0164] Subsequently, a first subpixel electrode 191h is formed in
the first subpixel area PXa, and a second subpixel electrode 191l
is formed in the second subpixel area PXb, by depositing and
patterning a transparent metal material, such as at least one of
indium tin oxide (ITO) and indium zinc oxide (IZO), on the first
insulating layer 240. The first subpixel electrode 191h and the
second subpixel electrode 191l are separated from each other with
the first valley V1 being positioned therebetween. The first
subpixel electrode 191h is connected to the first drain electrode
175h through the first contact hole 185h, and the second subpixel
electrode 191l is connected to the second drain electrode 175l
through the second contact hole 185l.
[0165] Horizontal stems 193h and 193l as well as vertical stems
192h and 192l crossing the horizontal stems 193h and 193l are
formed in the first subpixel electrode 191h and the second subpixel
electrode 191l, respectively. Further, a plurality of minute
branches 194h and 1941, which obliquely extend from the horizontal
stems 193h and 193l and the vertical stems 192h and 192l, is
formed.
[0166] Subsequently, a second insulating layer 250 may be formed on
the pixel electrode 191 using an inorganic insulating material,
such as at least one of silicon nitride (SiNx) and silicon oxide
(SiOx). The second insulating layer 250 may prevent a short circuit
between the pixel electrode 191 and the subsequently formed common
electrode 270. In an embodiment, support members 365 may not
overlap the pixel electrode 191 in a direction perpendicular to a
top surface of the pixel electrode, and the process for forming the
second insulating layer 250 may be omitted.
[0167] Referring to FIG. 11, a sacrificial layer 300 is formed by
coating a photosensitive organic material on the pixel electrode
191 and performing a photolithography process.
[0168] Portions of the sacrificial layer 300 are formed to be
connected to each other along the plurality of pixel columns. The
sacrificial layer 300 is formed to cover each pixel area PX and to
cover the first valley V1 positioned between the first subpixel
area PXa and the second subpixel area PXb.
[0169] A portion of the photosensitive organic material positioned
at the second valley V2 is removed by the photolithography process.
Openings 301 are formed by removing portions of the photosensitive
organic material through the photolithography process. Two openings
301 may be formed to be adjacent to two edges of the first valley
V1. A portion of the sacrificial layer 300 that is positioned
between two openings 301 may overlap a first valley V1. Portions of
the second insulating layer 250 may be exposed by the openings
301.
[0170] When the openings 301 are formed, groove portions 303 may be
formed on the sacrificial layer 300 by slit-exposing or
halftone-exposing the surroundings of the openings 301. In order to
form the groove portions 303, the sacrificial layer 300 may be
patterned using a slit mask or a halftone mask. Since a groove
portion 303 is formed by removing a part of the sacrificial layer
300, a portion of the sacrificial layer 300 that is associated with
the groove portion 303 has a smaller thickness (in a direction
perpendicular to a top surface of a pixel electrode 191) than other
portions of the sacrificial layer 300. A groove portion 303 may be
formed to surround an opening 301.
[0171] Referring to FIG. 12, a common electrode 270 is formed by
depositing a transparent metal material, such as at least one of
indium tin oxide (ITO) and indium zinc oxide (IZO), on the
sacrificial layer 300.
[0172] Subsequently, a third insulating layer 350 may be formed on
the common electrode 270 using an inorganic insulating material,
such as at least one of silicon oxide and silicon nitride.
[0173] Subsequently, a roof layer 360 is formed on the third
insulating layer 350 with an organic material, and support members
365 may formed in the openings 301. The roof layer 360 and the
support members 365 may be formed using the same material during
the same process. A support member 365 may be disposed between two
portions of the third insulating layer 350 and/or may be disposed
between two portions of the common electrode 270.
[0174] During a process of forming the roof layer 360 and the
openings 301, step members 362 may be formed in the groove portions
303 of the sacrificial layer 300. An organic material may be coated
on the entire substrate 110 after the third insulating layer 350
has been formed. The roof layer 360, the support members 365, and
the step members 362 may be substantially simultaneously formed
using the organic material. In an embodiment, the roof layer 360,
the support members 365, and the step members 362 may be formed
using the same material during the same process.
[0175] At least a portion of common electrode 270 and at least a
portion of the third insulating layer 350 are positioned between a
support member 365 and a pixel electrode 191, wherein the support
member 365 may overlap the pixel electrode 191. In an embodiment,
at least a portion of the second insulating layer 250 is disposed
between the pixel electrode 191 and the common electrode 270 and
may prevent short circuit between the pixel electrode 191 and the
common electrode 270. The portion of the second insulating layer
250 may directly contact each of the pixel electrode 191 and the
common electrode 270.
[0176] A support member 365 has a column shape in a cross-sectional
view of the display device. In a plan view of the display device,
the support member 365 may have one or more of various shapes, such
as a circle, a rectangle, and a triangle.
[0177] A portion of the roof layer material (i.e., the organic
material for forming the roof layer 360) that is positioned at the
first valley V1 may be removed by patterning the roof layer
material. As a result, as illustrated in FIG. 1, portions of the
roof layer 360 (or roof layers 360) may separately overlap pixel
rows.
[0178] Subsequently, referring to FIG. 13, a fourth insulating
layer 370 may be formed on the roof layer 360 with an inorganic
insulating material, such as at least one of silicon nitride (SiNx)
and silicon oxide (SiOx). The fourth insulating layer 370 is formed
on the patterned roof layer 360 to cover and protect sides of the
roof layer 360.
[0179] Referring to FIG. 14, portions of the fourth insulating
layer 370, the third insulating layer 350, and the common electrode
270 that are positioned at the first valley V1 are removed by
patterning the fourth insulating layer 370, the third insulating
layer 350, and the common electrode 270. As a result, a portion of
the sacrificial layer 300 that is positioned at the first valley V1
is exposed.
[0180] Subsequently, the sacrificial layer 300 is fully removed by
supplying a developer to the sacrificial layer 300. Alternatively
or additionally, the sacrificial layer 300 is fully removed using
an ashing process.
[0181] When the sacrificial layer 300 is removed, microcavities 305
may be formed at positions where the sacrificial layer 300 has been
previously positioned.
[0182] The pixel electrode 191 and the common electrode 270 are
spaced apart from each other with the microcavity 305 being
positioned therebetween, and the pixel electrode 191 and the roof
layer 360 are spaced apart from each other with the microcavity 305
being positioned therebetween. The common electrode 270 and the
roof layer 360 may cover the top of microcavity 305 and may at
least partially cover sides of the microcavity 305.
[0183] The microcavity 305 is exposed at an opening formed as a
result of removal of portions of the roof layer 360 and the common
electrode 270. The opening is called an injection hole 307. An
injection hole 307 may be formed along the first valley V1. In an
embodiment, a first injection hole 307 may be formed at a first
edge of the first subpixel area PXa, a second injection hole 307
may be formed at a first edge of the second subpixel area PXb. The
first edge of the first subpixel area PXa and the first edge of the
second subpixel area PXb may immediately neighbor each other and
may be positioned between a second edge of the first subpixel area
PXa and a second edge of the second subpixel area PXb. In an
embodiment, the first edge of the first subpixel area PXa may be a
lower edge of the first subpixel area PXa, and the first edge of
the second subpixel area PXb may be an upper edge of the second
subpixel area PXb. In an embodiment, the injection hole 307 may
also be formed along the second valley V2.
[0184] A support member 365 may be disposed adjacent to an
injection hole 307 and may be disposed in a microcavity 305. In an
embodiment, a microcavity 305 may have exactly two injection holes
307, wherein one of the two injection holes 307 may correspond to
(e.g., be adjacent to) one or more support members 365, and the
other one of the two injection holes 307 may correspond to no
support member 365.
[0185] In an embodiment, as illustrated in FIG. 1, support members
365 are formed along two sides of only one first valley V1 of two
immediately neighboring first valley V1. In an embodiment, as
illustrated in FIG. 1, support members 365 are formed in only one
pixel area row of two immediately neighboring pixel area rows.
[0186] A plurality of support members 365 may be formed at an edge
of a microcavity 305.
[0187] Subsequently, referring to FIG. 14, the roof layer 360 is
cured by applying heat to at least one of the roof layer 360 and
the substrate 110. As a result, the shape of the microcavity 305
may be maintained by the roof layer 360.
[0188] Subsequently, an aligning agent containing an alignment
material may be dropped on the substrate 110 using a spin coating
method and/or an inkjet method. The aligning agent may be provided
(e.g., injected) into the microcavity 305 through the injection
hole 307. Subsequently, a curing process may be performed. As a
result, a solution component may be evaporated, and an alignment
material may remain on the inner wall of the microcavity 305 to
form alignment layers 11 and 21.
[0189] The first alignment layer 11 may be formed on the pixel
electrode 191, and the second alignment layer 21 may be formed on
the common electrode 270. The first alignment layer 11 and the
second alignment layer 21 may overlap each other with the
microcavity 305 being positioned therebetween and may be connected
to each other at an edge of the pixel area PX.
[0190] In an embodiment, the alignment layers 11 and 21 may be
configured to substantially align liquid crystal molecules in a
vertical direction that is substantially perpendicular to the
substrate 110 (i.e., perpendicular to a surface of the substrate
110 that overlaps the roof layer 360, except, for example, at
positions where bead members 400 are located. In an embodiment, a
process of irradiating UV light on the alignment layers 11 and 21
may be performed; as a result, the alignment layers 11 and 21 may
be configured to substantially align liquid crystal molecules in a
horizontal direction that is substantially parallel to the
substrate 110.
[0191] During a drying process of the alignment layer, solids of
the aligning agent may concentrate near supporting member 365
during a drying process. In an embodiment, since the support
members 365 are positioned at an edge of a microcavity 305, the
concentrated solids of the aligning agent may not substantially
block light that is transmitted through the liquid crystal layer.
Therefore, the concentrated solids of the alignment agent may not
significant influence the image display quality of the display
device.
[0192] In an embodiment, the light blocking member 220 may overlap
support members 365 and may substantially overlap concentrated
solids of the aligning agent, such that influence of the
concentrated solids of the aligning agent on image display quality
may be minimized. Since supporting members are formed at an edge of
a microcavity 305, an area of a pixel that is overlapped by the
light blocking member 220 may be minimized. Advantageously, an
aperture ratio may be maximized.
[0193] Subsequently, referring to FIG. 14, liquid crystal material
that includes liquid crystal molecules 310 is provided (e.g.,
dropped) on the substrate 110 using an inkjet method or a
dispensing method. The liquid crystal material is provided (e.g.,
injected) into a microcavity 305 through a corresponding injection
hole 307. In an embodiment, liquid crystal material may be provided
(e.g., dropped) through injection holes 307 formed along only one
first valley V1 of two immediately neighboring first valleys V1
that does not correspond to support members 365. For example,
support members 365 are formed along two sides of each odd numbered
first valley V1, and liquid crystal material is dropped in only the
even-numbered first valleys V1 without being dropped in the
odd-numbered first valleys V1. As another example, support members
365 are formed along two sides of each even numbered first valley
V1, and liquid crystal material is dropped in only the odd-numbered
first valleys V1 without being dropped in the even-numbered first
valleys V1.
[0194] In an embodiment, liquid crystal material is provided to the
injection holes 307 formed along the odd-numbered first valleys V1,
and the liquid crystal material may enter the injection hole 307
through capillary action into the microcavity 305. As the liquid
crystal material enters into the microcavity 305, the liquid
crystal material may push the air in the microcavity 305 such that
the air may be discharged through the injection hole 307 formed
along the even-numbered first valley V1.
[0195] In an embodiment, since liquid crystal material is dropped
only one first valley V1 of two immediately neighboring first
valley V1 that does not correspond to support members 365,
potential obstruction caused by support members 365 and/or
concentrated solids of aligning agent may be substantially avoided.
Advantageously, the process time may be substantially minimized,
and associated costs may be minimized.
[0196] Subsequently, referring to FIG. 14, an encapsulation layer
390 is formed by depositing a material that does not substantially
(chemically) react with the liquid crystal molecules 310 on the
fourth insulating layer 370. The encapsulation layer 390 is formed
to cover the injection hole 307 for sealing the microcavity
305.
[0197] Subsequently, although not illustrated, a first polarizer
may be attached onto the lower side of the substrate 110, and a
second polarizer may be attached onto the encapsulation layer
390.
[0198] While this invention has been described in connection with
what is presently considered to be practical embodiments, it is to
be understood that the invention is not limited to the disclosed
embodiments. The invention is intended to cover various
modifications and equivalent arrangements included within the
spirit and scope of the appended claims.
TABLE-US-00001 <Description of symbols> 11: First alignment
layer 21: Second alignment layer 110: Substrate 121: Gate line 123:
Step-down gate line 124h: First gate electrode 124l: Second gate
electrode 124c: Third gate electrode 131: Storage electrode line
140: Gate insulating layer 154h: First semiconductor 154l: Second
semiconductor 154c: Third semiconductor 171: Data line 173h: First
source electrode 173l: Second source electrode 173c: Third source
electrode 175h: First drain electrode 175l: Second drain electrode
175c: Third drain electrode 180: Passivation layer 191: Pixel
electrode 191h: First subpixel electrode 191l: Second subpixel
electrode 220: Light blocking member 230: Color filter 240: First
insulating layer 250: Second insulating layer 270: Common electrode
300: Sacrificial layer 301: Opening 303: Groove portion 305:
Microcavity 307: Injection hole 310: Liquid crystal molecule 350:
Third insulating layer 360: Roof layer 362: Step member 365:
Support member 370: Fourth insulating layer 390: Encapsulation
layer
* * * * *