U.S. patent application number 15/084008 was filed with the patent office on 2016-07-21 for device for monitoring liquid crystal display and method for manufacturing liquid crystal display.
The applicant listed for this patent is Samsung Display Co., Ltd.. Invention is credited to You Young JIN, Won Tae KIM, Seon Uk LEE, Min Ho MOON, Hong Sick PARK, Sung Hwan WON.
Application Number | 20160211282 15/084008 |
Document ID | / |
Family ID | 51789559 |
Filed Date | 2016-07-21 |
United States Patent
Application |
20160211282 |
Kind Code |
A1 |
LEE; Seon Uk ; et
al. |
July 21, 2016 |
DEVICE FOR MONITORING LIQUID CRYSTAL DISPLAY AND METHOD FOR
MANUFACTURING LIQUID CRYSTAL DISPLAY
Abstract
A device for monitoring a liquid crystal display includes: a
substrate including a display region and a non-display region
disposed at an edge of the display region. The display region
includes: a thin film transistor disposed on the substrate, a pixel
electrode disposed on the substrate and connected to the thin film
transistor, a first sacrificial layer disposed on the pixel
electrode, and a roof layer disposed on the sacrificial layer. The
non-display region includes: a second sacrificial layer disposed on
the substrate, and the roof layer disposed on the second
sacrificial layer. The first sacrificial layer has a first
longitudinal dimension and a first cross-sectional area, and the
second sacrificial layer has a second longitudinal dimension and a
second cross-sectional area. The first cross-sectional area is the
same as the second cross-sectional area. The second longitudinal
dimension is greater than the first longitudinal dimension.
Inventors: |
LEE; Seon Uk; (Seongnam-si,
KR) ; KIM; Won Tae; (Suwon-si, KR) ; MOON; Min
Ho; (Anyang-si, KR) ; PARK; Hong Sick;
(Suwon-si, KR) ; WON; Sung Hwan; (Suwon-si,
KR) ; JIN; You Young; (Suwon-si, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Samsung Display Co., Ltd. |
Yongin-si |
|
KR |
|
|
Family ID: |
51789559 |
Appl. No.: |
15/084008 |
Filed: |
March 29, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13962366 |
Aug 8, 2013 |
9331109 |
|
|
15084008 |
|
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G02F 1/1309 20130101;
H01L 27/1248 20130101; H01L 27/1259 20130101 |
International
Class: |
H01L 27/12 20060101
H01L027/12; G02F 1/13 20060101 G02F001/13 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 24, 2013 |
KR |
10-2013-0045739 |
Claims
1. A device for monitoring a liquid crystal display, comprising: a
substrate comprising a display region and a non-display region
disposed at an edge of the display region, wherein the display
region comprises: a thin film transistor disposed on the substrate;
a pixel electrode disposed on the substrate and connected to the
thin film transistor; a first sacrificial layer disposed on the
pixel electrode; and a roof layer disposed on the first sacrificial
layer, wherein the non-display region comprises: a second
sacrificial layer disposed on the substrate; and the roof layer
disposed on the second sacrificial layer, and wherein: the first
sacrificial layer has a first longitudinal dimension and a first
cross-sectional area; the second sacrificial layer has a second
longitudinal dimension and a second cross-sectional area; the first
cross-sectional area and the second cross-sectional area are the
same as one another; and the second longitudinal dimension is
longer than the first longitudinal dimension.
2. The device for monitoring a liquid crystal display of claim 1,
wherein: the first sacrificial layer is configured to be completely
removed over a first processing time; and in association with a
second processing time longer than the first processing time, the
second sacrificial layer is configured to facilitate confirmation
of the complete removal of the first sacrificial layer and a degree
of removal of the second sacrificial layer is determined by
monitoring the degree of etching of the second sacrificial
layer.
3. The device for monitoring a liquid crystal display of claim 2,
wherein the second processing time is at least 150% greater than
the first process time.
4. The device for monitoring a liquid crystal display of claim 3,
wherein the second sacrifical layer comprises: a first section
where the degree of etching of the second sacrificial layer ranges
from 100% of the first longitudinal dimension to a first upper
limit percentage value of the first longitudinal dimension; and a
second section where the degree of etching the second sacrificial
layer ranges from the first upper limit percentage value to a
second upper limit percentage value of the first longitudinal
dimension, wherein the first upper limit percentage value is
greater than 100%, and wherein the second upper limit percentage
value is greater than the first upper limit percentage value.
5. The device for monitoring a liquid crystal display of claim 4,
wherein the second sacrificial layer further comprises: a third
section where the degree of etching of the second sacrificial layer
is 100% or less of the first longitudinal dimension.
6. The device for monitoring a liquid crystal display of claim 5,
wherein, when the degree of etching at least extends to the first
or third sections, the second sacrifical layer is configured to
indicate replacement of an initial sacrificial layer removal
composition.
7. The device for monitoring a liquid crystal display of claim 1,
wherein the peripheral region further comprises: a dummy
sacrificial layer disposed adjacent to the second sacrificial
layer, wherein the dummy sacrificial layer has the same
cross-sectional area as the second sacrificial layer.
8. The device for monitoring a liquid crystal display of claim 7,
wherein the second longitudinal dimension is at least 150% greater
than the first longitudinal dimension.
9. The device for monitoring a liquid crystal display of claim 8,
wherein the second sacrifical layer comprises gradations marked
along the second longitudinal dimension to indicate an extent of
removal.
10. The device for monitoring a liquid crystal display of claim 9,
wherein the gradations are marked on a partition structure disposed
adjacent to the second sacrificial layer, the partition structure
comprising an insulating layer.
11. The device for monitoring a liquid crystal display of claim 1,
wherein: the first sacrificial layer is one of a plurality of first
sacrificial layers in a pattern of first sacrificial layers
disposed in a pixel region of the liquid crystal display; the
second sacrificial layer is one of a plurality of second
sacrificial layers in a pattern of second sacrificial layers; and a
separation distance between ones of the plurality of first
sacrificial layers is the same as a separation distance between
ones of the plurality of second sacrificial layers.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Divisional of U.S. patent application
Ser. No. 13/962,366, filed on Aug. 8, 2013, and claims priority
from and the benefit of Korean Patent Application No.
10-2013-0045739, filed on Apr. 24, 2013, which is hereby
incorporated by reference for all purposes as if set forth
herein.
BACKGROUND
[0002] 1. Field
[0003] Exemplary embodiments relate to display technology, and,
more particular, to a device for monitoring a liquid crystal
display and a method for manufacturing the liquid crystal
display.
[0004] 2. Discussion
[0005] Conventional liquid crystal displays typically include two
display panels having field generating electrodes, such as a pixel
electrode and a common electrode, and a liquid crystal layer
disposed therebetween. In this manner, traditional liquid crystal
displays are configured to display an image by applying a voltage
to one or more of the field generating electrodes, which, in turn,
imposes an electric field on the liquid crystal layer.
[0006] The imposition of the electric field is configured to affect
the alignment of liquid crystal molecules of the liquid crystal
layer, and, thereby, control the polarization of incident
light.
[0007] One type of conventional liquid crystal display is a
nanocrystal liquid crystal display (NCD), in which a display panel
is manufactured by forming a sacrificial layer using, for example,
an organic material, or the like, forming a support member on an
upper portion of the sacrificial layer, removing the sacrificial
layer, and filling liquid crystal in a microcavity formed by the
removal of the sacrificial layer. Since the sacrificial layer is
surrounded by a support structure (e.g., a supporting layer), an
etching (or stripping) material (or solution) is typically utilized
to remove the sacrificial layer. In this this manner, the etching
material is usually injected into an injection hole to reach the
sacrificial layer. The processing time to etch an exposed target
through an injection hole, however, can be relatively long, and,
thereby, may increase the cost to manufacture the display device.
Also, if the etching material is repeatedly used, an etching speed
may be reduced, which may result in portions of the sacrificial
layer not being fully removed.
[0008] The above information disclosed in this Background section
is only for enhancement of understanding of the background of the
invention, and, therefore, it 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] Exemplary embodiments provide a device for monitoring a
liquid crystal display and a method for manufacturing the liquid
crystal display to reduce the processing time and prevent (or
otherwise reduce) the occurrence of portions of the sacrificial
layer not being fully removed.
[0010] Additional aspects will be set forth in the detailed
description which follows and, in part, will be apparent from the
disclosure, or may be learned by practice of the invention.
[0011] According to exemplary embodiments, a device for monitoring
a liquid crystal display, includes: a substrate including a display
region and a non-display region disposed at an edge of the display
region. The display region includes: a thin film transistor
disposed on the substrate, a pixel electrode disposed on the
substrate and connected to the thin film transistor, a first
sacrificial layer disposed on the pixel electrode, and a roof layer
disposed on the first sacrificial layer. The peripheral region
includes: a second sacrificial layer disposed on the substrate, and
the roof layer disposed on the second sacrificial layer. The first
sacrificial layer has a first longitudinal dimension and a first
cross-sectional area, and the second sacrificial layer has a second
longitudinal dimension and a second cross-sectional area. The first
cross-sectional area is the same as the second cross-sectional
area. The second longitudinal dimension is longer than the first
longitudinal dimension.
[0012] According to exemplary embodiments, a method for
manufacturing a liquid crystal display, includes: applying a
sacrificial layer forming material on a substrate including a
display region and a non-display region, patterning the sacrificial
layer forming material using a mask to form a first sacrificial
layer in the display region and a second sacrificial layer in the
non-display region, forming a roof layer to cover the first
sacrificial layer and the second sacrificial layer, and
simultaneously etching the first sacrificial layer and the second
sacrificial layer. The first sacrificial layer has a first
longitudinal dimension and a first cross-sectional area, and the
second sacrificial layer has a second longitudinal dimension and a
second cross-sectional area. The first cross-sectional area is the
same as the second cross-sectional area. The second longitudinal
dimension is longer than the first longitudinal dimension.
[0013] According to exemplary embodiments, the use of, for example,
one or more etching materials is monitored in various regions
during the formation of a display device and is replaced to prevent
(or otherwise reduce) the occurrence of a portion of the
sacrificial layer from not being fully removed, as well as to
reduce the processing time and cost of the associated display
device.
[0014] The foregoing general description and the following detailed
description are exemplary and explanatory and are intended to
provide further explanation of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The accompanying drawings, which are included to provide a
further understanding of the invention and are incorporated in and
constitute a part of this specification, illustrate exemplary
embodiments of the invention, and together with the description
serve to explain the principles of the invention.
[0016] FIG. 1 is a layout view of a device for monitoring a liquid
crystal display, according to exemplary embodiments.
[0017] FIG. 2 is a perspective view of a portion of a display
region and a peripheral region of the display device of FIG. 1,
according to exemplary embodiments.
[0018] FIG. 3 is a cross-sectional view of the respective portions
of FIG. 2 taken along sectional lines and III'-III'', according to
exemplary embodiments.
[0019] FIG. 4 is a cross-sectional view of the respective portions
of FIG. 2 taken along sectional lines IV-IV' and IV'-IV'',
according to exemplary embodiments.
[0020] FIG. 5 schematically illustrates an over-etching degree used
by a device for monitoring a liquid crystal display, according to
exemplary embodiments.
[0021] FIG. 6 is a plan view of the device for monitoring a liquid
crystal display, according to exemplary embodiments.
[0022] FIG. 7 is a plan view of a liquid crystal display, according
to exemplary embodiments.
[0023] FIG. 8 is a cross-sectional view of the liquid crystal
display of FIG. 7 taken along sectional line VIII-VIII, according
to exemplary embodiments.
[0024] FIG. 9 is a cross-sectional view of the display device of
FIG. 7 taken along sectional line IX-IX, according to exemplary
embodiments.
DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS
[0025] In the following description, for the purposes of
explanation, numerous specific details are set forth in order to
provide a thorough understanding of various exemplary embodiments.
It is apparent, however, that various exemplary embodiments may be
practiced without these specific details or with one or more
equivalent arrangements. In other instances, well-known structures
and devices are shown in block diagram form in order to avoid
unnecessarily obscuring various exemplary embodiments.
[0026] In the accompanying figures, the size and relative sizes of
layers, films, panels, regions, etc., may be exaggerated for
clarity and descriptive purposes. Also, like reference numerals
denote like elements.
[0027] When an element or layer is referred to as being "on,"
"connected to," or "coupled to" another element or layer, it may be
directly on, connected to, or coupled to the other element or layer
or intervening elements or layers may be present. When, however, an
element or layer is referred to as being "directly on," "directly
connected to," or "directly coupled to" another element or layer,
there are no intervening elements or layers present. For the
purposes of this disclosure, "at least one of X, Y, and Z" and "at
least one selected from the group consisting of X, Y, and Z" may be
construed as X only, Y only, Z only, or any combination of two or
more of X, Y, and Z, such as, for instance, XYZ, XYY, YZ, and ZZ.
Like numbers refer to like elements throughout. As used herein, the
term "and/or" includes any and all combinations of one or more of
the associated listed items.
[0028] Although the terms first, second, etc., may be used herein
to describe various elements, components, regions, layers, and/or
sections, these elements, components, regions, layers, and/or
sections should not be limited by these terms. These terms are used
to distinguish one element, component, region, layer, or section
from another element, component, region, layer, or section. Thus, a
first element, component, region, layer, or section discussed below
could be termed a second element, component, region, layer, or
section without departing from the teachings of the present
disclosure.
[0029] Spatially relative terms, such as "beneath," "below,"
"lower," "above," "upper," and/or the like, may be used herein for
descriptive purposes, and, thereby, to describe one element or
feature's relationship to another element(s) or feature(s) as
illustrated in the drawings. Spatially relative terms are intended
to encompass different orientations of an apparatus in use or
operation in addition to the orientation depicted in the drawings.
For example, if the apparatus in the drawings is turned over,
elements described as "below" or "beneath" other elements or
features would then be oriented "above" the other elements or
features. Thus, the exemplary term "below" can encompass both an
orientation of above and below. Furthermore, the apparatus may be
otherwise oriented (e.g., rotated 90 degrees or at other
orientations), and as such, the spatially relative descriptors used
herein interpreted accordingly.
[0030] The terminology used herein is for the purpose of describing
particular embodiments and is not intended to be limiting. As used
herein, the singular forms "a," "an," and "the" are intended to
include the plural forms as well, unless the context clearly
indicates otherwise. Moreover, the terms "comprises" and/or
"comprising," when used in this specification, specify the presence
of stated features, integers, steps, operations, elements, and/or
components, but do not preclude the presence or addition of one or
more other features, integers, steps, operations, elements,
components, and/or groups thereof.
[0031] Unless otherwise defined, all terms (including technical and
scientific terms) used herein have the same meaning as commonly
understood by one of ordinary skill in the art to which this
disclosure is a part. Terms, such as those defined in commonly used
dictionaries, should be interpreted as having a meaning that is
consistent with their meaning in the context of the relevant art
and will not be interpreted in an idealized or overly formal sense,
unless expressly so defined herein.
[0032] While exemplary embodiments are described in association
with liquid crystal display (LCD) devices, it is contemplated that
exemplary embodiments may be utilized in association with other or
equivalent display devices, such as various self-emissive and/or
non-self-emissive display technologies. For instance, self-emissive
display devices may include organic light emitting displays (OLED),
plasma display panels (PDP), etc., whereas non-self-emissive
display devices may include electroluminescent (EL) displays,
electrophoretic displays (EPD), electrowetting displays (EWD),
etc.
[0033] FIG. 1 is a layout view of a device for monitoring a liquid
crystal display, according to exemplary embodiments. FIG. 2 is a
perspective view of a portion of a display region and a peripheral
region of the display device of FIG. 1. FIG. 3 is a cross-sectional
view of the respective portions of FIG. 2 taken along sectional
lines and III'-III'', according to exemplary embodiments. FIG. 4 is
a cross-sectional view of the respective portions of FIG. 2 taken
along sectional lines IV-IV' and IV'-IV'', according to exemplary
embodiments.
[0034] Referring to FIG. 1, a device for monitoring a liquid
crystal display includes a substrate 110, which includes a display
region DP and a non-display region (such as a peripheral region)
NDP. The display region DP is a region in which one or more signal
lines, one or more thin film transistors, and one or more field
generating electrodes are formed to facilitate the display of an
image for presentation to an observer. The non-display region NDP
may be a region positioned at one or more edge portions of the
display region DP, and, for example, surrounds the display region
DP. In this manner, the non-display region NDP may bound the
display region DP. As such, the non-display region NDP may be
interchangeably referred to herein as "the non-display region" or
the "peripheral region" NDA. To this end, the non-display region
NDP may be a region in which an image is not presented. In
exemplary embodiments, one or more driving units (not shown) and/or
other components may be positioned.
[0035] According to exemplary embodiments, a first sacrificial
layer 300a is disposed at a position corresponding to a pixel
region in the display region DP, and a second sacrificial layer
300b is disposed in the peripheral region NDP. In exemplary
embodiments, the second sacrificial layer 300b may have the same
shape and/or configuration as the first sacrificial layer 300a. It
is contemplated, however, that the shape, configuration, etc., of
the first and second sacrificial layers 300a and 300b may be
different. As will become more apparent below, when the
configurations of the first and second sacrificial layers 300a and
300b are different, the respective configurations may be provided
to enable a rate of etching to be the same for the first and second
sacrificial layers 300a and 300b. To this end, the first
sacrificial layer 300a and the second sacrificial layer 300b may be
formed of any suitable material, such as, for example, an organic
material, e.g., photoresist.
[0036] Referring to FIG. 2, a region P1, which is an illustrative
portion of the display region DP, includes the first sacrificial
layer 300a, which is one of a plurality of first sacrificial layers
300a in a pattern of first sacrificial layers 300a disposed
adjacent to each other. Each of the first sacrificial layers 300a
longitudinally extends in a sacrificial layer etching direction D1,
which is described in more detail later.
[0037] Region P2 is a portion of the peripheral region NDP and
includes the second sacrificial layer 300b, which is one of a
plurality of second sacrificial layers 300b in a pattern of second
sacrificial layers 300b disposed adjacent to each other. Although
the drawings illustrate a plurality of second sacrificial layers
300b, it is contemplated that only one second sacrificial layer
300b may be provided. Each of the second sacrificial layers 300b
longitudinally extends in the sacrificial layer etching direction
D1. It is contemplated, however, that the second sacrificial layers
300b may extend in a different direction than the first sacrificial
layers 300a. In exemplary embodiments, a separation distance (or
pitch) between first sacrificial layers 300a in the pattern of
first sacrificial layers 300a and a separation distance between
second sacrificial layers 300b in the pattern of second sacrificial
layers 300b may be the same as each other. It is contemplated,
however, that they may be different.
[0038] According to exemplary embodiments, a first sacrificial
layer 300a has a first length d1 and a first cross-sectional area
S1 in the sacrificial layer etching direction D1. The second
sacrificial layer 300b has a second length d2 and a second
cross-sectional area S2 in the sacrificial layer etching direction
D1. The first cross-sectional area S1 of the first sacrificial
layer 300a and the second cross-sectional area S2 of the second
sacrificial layer 300b may be the same as each other, but the
second length d2 of the second sacrificial layer 300b may be longer
than the first length d1 of the first sacrificial layer 300a. It is
contemplated; however, that other relationships may be utilized.
For instance, the first and second cross-sectional areas S1 and S2
may be different, the first and second lengths d1 and d2 may be the
same, the first length d1 may be longer than the second length d2,
etc.
[0039] In exemplary embodiments, the same mask may be used in order
to form the first sacrificial layers 300a and the second
sacrificial layers 300b having the aforementioned shape, where
S1=S2 and d2>d1.
[0040] Referring to FIGS. 3 and 4, a common electrode 270 is
positioned on the first sacrificial layer 300a. The common
electrode 270 may or may not be positioned on the second
sacrificial layer 300b formed in the peripheral region NDP.
[0041] A first (e.g., lower) insulating layer 350 is positioned on
the common electrode 270 and the second sacrificial layer 300b. The
lower insulating layer 350 may be formed of any suitable insulating
material, such as, for example, silicon nitride (SiNx), silicon
oxide (SiOx). A roof layer 360 is positioned on the lower
insulating layer 350. The roof layer 360 may include any suitable
material, such as, for instance, silicon oxycarbide (SiOC),
photoresist, and/or any other suitable organic material(s).
[0042] A second (e.g., upper) insulating layer 370 is positioned on
the roof layer 360. The upper insulating layer 370 may be formed of
any suitable insulating material, such as, for instance, silicon
nitride (SiNx), silicon oxide (SiOx), etc.
[0043] According to exemplary embodiments, the roof layer 360
and/or one or more other layers (e.g.., portions of the common
electrode 270 and/or the lower insulating layer 350) fill a space
between the first sacrificial layers 300a and a space between the
second sacrificial layers 300b, these spaces being disposed between
first sacrificial layers 300a or second sacrificial layers 300b
that are adjacent to one another in a second (e.g., horizontal)
direction. The second direction may relate to a direction of
longitudinal extension of one or more gate lines, which are
described in more detail in association with FIG. 7. To this end,
the second direction may be perpendicular (or substantially
perpendicular) to the etching direction D1. In this manner, the
roof layer 360 forms a partition forming portion PWP. The partition
forming portion PWP serves to support microcavities from when the
first sacrificial layer 300a and the second sacrificial layer 300b
are removed.
[0044] A liquid crystal injection hole forming region 307FP is
positioned between the first sacrificial layers 300a and between
the second sacrificial layers 300b, which are adjacent to one
another in a first (e.g., vertical) direction, which may correspond
to the longitudinal extension direction of a data line, which is
descried in more detail in association with FIG. 7. In this manner,
the exposed portions of the first sacrificial layer 300a and the
second sacrificial layer 300b may begin to be etched from an inlet
portion 307.
[0045] As illustrated in FIGS. 3 and 4, the space between the first
sacrificial layers 300a and the space between the second
sacrificial layers 300b, which are adjacent to one another in a
horizontal direction, are surrounded by the partition forming
portion PWP, such as the roof layer 360. The space between the
first sacrificial layers 300a and the space between the second
sacrificial layers 300b, which are adjacent to one another in a
vertical direction, are etched in a vertical direction since the
first sacrificial layers 300a and the second sacrificial layers
300b are exposed via the liquid crystal injection hole forming
region 307FP. In other words, the sacrificial layer etching
direction D1 may be the aforementioned vertical direction.
[0046] According to exemplary embodiments, if the duration over
which the first sacrificial layer 300a is completely removed by an
initial sacrificial layer removal etchant (e.g., a liquid chemical)
is considered a first processing time, then the first sacrificial
layer 300a and the second sacrificial layer 300b may be etched (or
otherwise removed) over a second processing time (or duration) that
is about 120% to 150%, e.g., about 130% to 140%, of the first
process time. In this manner, the second processing time may be
longer than the first processing time, and may be a length of time
about 150% of the first processing time. To this end, etching the
first sacrificial layers 300a and the second sacrificial layers
300b over the second processing time prevents (or otherwise
reduces) the potential of the first sacrificial layers 300a from
not being completely etched or otherwise removed. It is
contemplated, however, that the second processing time may be
greater than the first processing time by any suitable amount, and,
therefore, exemplary embodiments are not to be limited by the
aforementioned 120% to 150% numerical range.
[0047] A device for monitoring the liquid crystal display,
according to exemplary embodiments, may confirm complete removal of
the first sacrificial layer 300a and an amount (or degree) of
over-etching of the second sacrificial layer 300b during the second
processing time. This is described in more detail in association
with FIGS. 5 and 6.
[0048] FIG. 5 schematically illustrates an over-etching degree used
by a device for monitoring a liquid crystal display, according to
exemplary embodiments.
[0049] As seen in FIG. 5, the amount or degree of over-etching of
the second sacrificial layer 300b in the sacrificial layer etching
direction D1 is a percentage, and a section where the amount of
over-etching of the second sacrificial layer 300b ranges from 100%
of the first length d1 of the first sacrificial layer 300a to 120%
of the first length d1 may be defined as a "warning" section, and a
section where the degree of over-etching ranges from 120% of the
first length d1 to 150% of the first length d1 may be defined as a
"normal" section.
[0050] In exemplary embodiments, etching lengths of the first
sacrificial layer 300a and the second sacrificial layer 300b are in
proportion to the etching processing times, and, thereby, the
relative configurations of the first and second sacrificial layers
300a and 300b. For instance, when the degree of etching of the
second sacrificial layer 300b does not reach 100% of the first
length (d1), then the first sacrificial layer 300a is not
completely removed, and, as such, at least a portion thereof
remains. This section may be defined as a "remaining portion"
section. When 120% of the first length d1 is a first upper limit
value (%) and 150% of the first length d1 is a second upper limit
value (%), the first upper limit value (%) and the second upper
limit value (%) may be adjusted based on the individual and
relative configurations of the first and second sacrificial layers
300a and 300b.
[0051] According to exemplary embodiments, when the device provides
an indication that the degree of over-etching of the second
sacrificial layer 300b is in the warning section or the remaining
portion section, then it may be determined that it is time to
replace the initial sacrificial layer removal etchant (e.g., liquid
chemical) with new (or fresh) sacrificial layer removal
etchant.
[0052] FIG. 6 is a plan view of the device for monitoring the
liquid crystal display, according to exemplary embodiments.
[0053] Referring to FIG. 6, a dummy sacrificial layer 300c is
formed adjacent to the second sacrificial layer 300b. The dummy
sacrificial layer 300c has the same cross-section as the second
sacrificial layer 300b, but may have a smaller length than the
second sacrificial layer 300b in the sacrificial layer etching
direction D1. The dummy sacrificial layer 300c serves to construct
an etching environment that is similar to that of the first
sacrificial layers 300a included in the display region DP. For
example, the first sacrificial layer 300a included in the display
region DP may be one of a plurality of first sacrificial layers
300a in a pattern of first sacrificial layers 300a. To this end,
the second sacrificial layer 300b may be formed of one sacrificial
layer 300b. In this manner, the dummy sacrificial layer 300c may
serve to correspond to another second sacrificial layer 300b
adjacent to the one second sacrificial layer 300b, so that the
etching conditions for the one second sacrificial layer 300b is
similar to the etching conditions of the first sacrificial layer
300a in the pattern of first sacrificial layers 300a.
[0054] According to exemplary embodiments, the second sacrificial
layer 300b includes gradations marked along its longitudinal
dimension to facilitate confirmation of the degree of over-etching
of the second sacrificial layer 300b. For instance, the second
sacrificial layer 300b may at least include gradations associated
with each of the aforementioned warning, normal, and remaining
portion sections. It is contemplated, however, that one or more
intermediary gradations may be provided between the aforementioned
warning, normal, and remaining portion sections. In this manner,
the gradations may be provided at any suitable level of
granularity.
[0055] A method for manufacturing the liquid crystal display using
the aforementioned device for monitoring the liquid crystal display
will be described in association with FIGS. 1-4.
[0056] Referring to FIGS. 1-4, in the method for manufacturing the
liquid crystal display, a sacrificial layer forming material is
applied on a substrate 110 including a display region DP and a
peripheral region NDP.
[0057] The sacrificial layer forming material is patterned using a
mask to form first sacrificial layers 300a in the display region DP
and form one or more second sacrificial layers 300b in the
peripheral region NDP. The first sacrificial layers 300a and the
one or more second sacrificial layers 300b may be formed so that
each of the first sacrificial layers 300a have a first length d1
and a first cross-sectional area S1 and the one or more second
sacrificial layer 300b have a second length d2 and a second
cross-sectional area S2. The first cross-sectional area S1 and the
second cross-sectional area S2 may be the same as each other, and
the second length d2 may be longer than the first length d1.
[0058] A roof layer 360 is formed to cover the first sacrificial
layers 300a and the one or more second sacrificial layers 300b.
Before the roof layer 360 is formed, a common electrode 270 and a
lower insulating layer 350 may be formed, and the common electrode
270 may be formed on just the first sacrificial layers 300a or on
both the first sacrificial layers 300a and one or more of the
second sacrificial layers 300b. An upper insulating layer 370 is
formed on the roof layer 360.
[0059] The first sacrificial layers 300a and the one or more second
sacrificial layer 300b may be simultaneously etched over a
determined second processing time. If a duration of time for which
it takes the first sacrificial layers 300a to be completely removed
by an initial sacrificial layer removal etchant (e.g., liquid
chemical) is a first processing time, the second processing time
may be longer than the first processing time, and may be about 150%
of the first processing time.
[0060] When the first sacrificial layer 300a is completely removed
during the second processing time, a degree of over-etching of the
second sacrificial layer 300b may be monitored and confirmed. In
this manner, as described above, a section where the degree of
over-etching of the second sacrificial layer 300b ranges from 100%
of the first length d1 to a determined first upper limit value (%)
of the first length d1 may be defined as a warning section, and a
section where the degree of over-etching ranges from the determined
first upper limit value (%) to a determined second upper limit
value (%) may be defined as a normal section. To this end, the
determined first upper limit value (%) may be larger than 100%, and
the determined second upper limit value (%) may be set to be larger
than the first upper limit value (%). Further, when the degree of
etching of the second sacrificial layer 300b does not reach 100% of
the first length d1, it is known that the first sacrificial layer
300a is not completely removed, and, thereby, a portion thereof
remains. This section may be defined as a remaining portion
section.
[0061] When the degree of over-etching of the second sacrificial
layer 300b is included in the warning section or the remaining
portion section, the sacrificial layer removal etchant (e.g.,
liquid chemical) may be replaced. In this manner, after the first
sacrificial layer 300a is completely removed, those structures
including the second sacrificial layer 300b positioned in the
peripheral region NDP may be removed.
[0062] The device for monitoring the liquid crystal display and the
liquid crystal display formed by the manufacturing method will be
described in association with FIGS. 7-9.
[0063] FIG. 7 is a plan view of a liquid crystal display, according
to exemplary embodiments. FIG. 8 is a cross-sectional view of the
liquid crystal display of FIG. 7 taken along sectional line
VIII-VIII, whereas FIG. 9 is a cross-sectional view of the liquid
crystal display of FIG. 7 taken along sectional line IX-IX.
[0064] With continued reference to FIGS. 1-3, a gate line 121 and a
storage electrode line 131 are formed on an insulation substrate
110 made of any suitable material, such as, for example,
transparent glass, plastic, and/or the like. The gate line 121
includes a gate electrode 124. The storage electrode line 131
mainly extends in the second (e.g., horizontal) direction and is
configured to transfer a predetermined voltage, such as a common
voltage (Vcom). The storage electrode line 131 includes a pair of
vertical portions 135a that extend substantially vertical to the
gate line 121, and a horizontal portion 135b connecting ends of the
pair of vertical portions 135a to each other. The storage
electrodes 135a and 135b have a structure surrounding a pixel
electrode 191.
[0065] A gate insulating layer 140 is formed on the gate line 121
and the storage electrode line 131. A semiconductor layer 151
positioned on a lower portion of a data line 171, and a
semiconductor layer 154 positioned on lower portions of
source/drain electrodes 173 and 175 and a channel portion of a thin
film transistor Q are formed on the gate insulating layer 140.
[0066] A plurality of ohmic contacts (not shown) may be formed on
each semiconductor layer 151 and 154, and between the data line 171
and the source/drain electrodes 173 and 175.
[0067] Data conductors 171, 173, and 175 including the source
electrode 173, the data line 171 connected to the source electrode
173, and the drain electrode 175 are formed on each of the
semiconductor layers 151 and 154 and the gate insulating layer
140.
[0068] The gate electrode 124, the source electrode 173, and the
drain electrode 175 form a thin film transistor Q together with the
semiconductor layer 154, and a channel of the thin film transistor
Q is formed at the semiconductor layer portion 154 between the
source electrode 173 and the drain electrode 175.
[0069] A first interlayer insulating layer 180a is formed on the
data conductors 171, 173, and 175 and the exposed portion of the
semiconductor layer 154. The first interlayer insulating layer 180a
may include any suitable inorganic insulator, such as, for example,
silicon nitride (SiNx), silicon oxide (SiOx), etc., and/or any
suitable organic insulator.
[0070] A color filter 230 and a light blocking member (black
matrix) 220 are formed on the first interlayer insulating layer
180a.
[0071] The light blocking member 220 has a lattice structure
including an opening corresponding to a region for displaying an
image, and is formed of any suitable material through which light
does not penetrate. The color filter 230 is formed in the opening
of the light blocking member 220. In exemplary embodiments, the
light blocking member 220 is open over the thin film transistor Q
in order to enable the thin film transistor Q to be repaired or
otherwise modified during one or more subsequent manufacturing
processes. In other words, the opening of the light blocking member
220 may be formed to include a region over which the thin film
transistor Q is formed.
[0072] The color filter 230 may facilitate the display of any
suitable color, such as one of the primary color, e.g., red, green,
and blue colors. It is contemplated, however, that the color filter
230 may facilitate the display of other colors, such as, for
instance, cyan, magenta, yellow, white-based colors, etc. The color
filter 230 may be formed of any suitable material(s) configured to
enable displaying different colors for each of the adjacent
pixels.
[0073] A second interlayer insulating layer 180b is formed on the
color filter 230 and the light blocking member 220 to cover the
color filter 230 and the light blocking member 220. The second
interlayer insulating layer 180b may include any suitable inorganic
insulator, such as, for instance, silicon nitride (SiNx), silicon
oxide (SiOx), etc., and/or any suitable organic insulator. Unlike
as shown in FIG. 2, when a step occurs due to a difference in
thicknesses of the color filter 230 and the light blocking member
220, the second interlayer insulating layer 180b may be provided to
reduce or remove the step.
[0074] A contact hole 185, through which the drain electrode 175 is
exposed, is formed in the color filter 230, the light blocking
member 220, and the interlayer insulating layers 180a and 180b.
[0075] The pixel electrode 191 is formed on the second interlayer
insulating layer 180b. The pixel electrode 191 may be made of any
suitable transparent conductive material, such as, for instance,
aluminum zinc oxide (AZO), gallium zinc oxide (GZO), indium tin
oxide (ITO), indium zinc oxide (IZO), indium tin zinc oxide (ITZO),
etc. It is also contemplated that one or more conductive polymers
(ICP) may be utilized, such as, for example, polyaniline,
poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate)
(PEDOT:PSS), etc.
[0076] The "overall" shape of the pixel electrode 191 may form a
quadrilateral configuration; however, any other suitable
configuration may be utilized. As shown, the pixel electrode 191
includes a cross-shaped stem portion formed of a horizontal stem
portion 191a and a vertical stem portion 191b crossing the
horizontal stem portion 191a. Further, the pixel electrode 191 may
be divided into a plurality of sub-regions (e.g., four sub-regions)
by the horizontal stem portion 191a and the vertical stem portion
191b. Each sub-region may include a plurality of fine branch
portions 191c. Further, in exemplary embodiments, an outskirt stem
portion surrounding an outskirt of the pixel electrode 191 may be
included.
[0077] The fine branch portion 191c of the pixel electrode 191
forms an angle of about 40.degree. to 45.degree. with the gate line
121 or the horizontal stem portion 191a. Further, the fine branch
portions 191c of two adjacent sub-regions may be orthogonal (or
substantially orthogonal) to each other. Further, a width of the
fine branch portion 191c may be gradually increased, and intervals
between the fine branch portions 191c may be the same or different
from each other.
[0078] The pixel electrode 191 is physically and electrically
connected to the drain electrode 175 through the contact hole 185,
and receives a data voltage from the drain electrode 175.
[0079] The aforementioned descriptions of the thin film transistor
Q and the pixel electrode 191 are merely exemplary, and a thin film
transistor structure (or switching element) and a pixel electrode
design may be modified to, for example, improve lateral surface
visibility, etc.
[0080] A first (e.g., lower) alignment layer 11 is formed on the
pixel electrode 191, and the lower alignment layer 11 may be a
vertical alignment layer. The lower alignment layer 11 may be
formed including any suitable material generally used as a liquid
crystal is alignment layer, such as polyamic acid, polysiloxane,
polyimide, etc.
[0081] A second (e.g., upper) alignment layer 21 is positioned on a
portion facing the lower alignment layer 11. A microcavity 305 is
formed between the lower alignment layer 11 and the upper alignment
layer 21. Liquid crystal material including liquid crystal
molecules 310 is injected into the microcavity 305, and the
microcavity 305 has a liquid crystal injection hole 307. The
microcavity 305 may be formed in a column direction of the pixel
electrode 191, or, in other words, a vertical direction. In
exemplary embodiments, the alignment material forming the alignment
layers 11 and 21 and the liquid crystal material including the
liquid crystal molecule 310 may be injected into the microcavity
305 using a capillary force.
[0082] According to exemplary embodiments, the microcavity 305 may
be formed based on the aforementioned device for monitoring the
liquid crystal display. For example, in FIG. 3, since the
microcavity is formed by removing the first sacrificial layer 300a
and defects may be caused if the first sacrificial layer 300a is
not completely removed, the etchant (e.g., liquid chemical) for
removing the first sacrificial layer 300a may be replaced according
to the aforementioned device for monitoring the liquid crystal
display and method for manufacturing the liquid crystal display.
This may be done to prevent or otherwise reduce the occurrence of
defects.
[0083] The microcavity 305 is divided in a vertical direction by a
plurality of liquid crystal injection hole forming regions 307FP
positioned at an overlapping portion with the gate line 121, and is
formed in plural in an extension direction of the gate line 121.
Each of the microcavities 305 formed in plural may correspond to
the pixel region, and the pixel region may correspond to a region
utilized to display an image. In exemplary embodiments, since the
liquid crystal material is injected through the liquid crystal
injection hole 307 of the microcavity 305, the liquid crystal
display may be formed without forming a separate upper
substrate.
[0084] A common electrode 270 and a lower insulating layer 350 are
positioned on the upper alignment layer 21. The common electrode
270 receives a common voltage and forms an electric field together
with the pixel electrode 191 to which a data voltage is applied.
The imposition of the electric field may be utilized to control an
inclination direction of the liquid crystal molecules 310
positioned in the microcavity 305 between the two electrodes 191
and 270. The common electrode 270 and the pixel electrode 191 form
a capacitor, which is configured to maintain the applied voltage
for a duration of time after the thin film transistor is "turned
off". The lower insulating layer 350 may be formed of any suitable
material, such as, for example, silicon nitride (SiNx), silicon
oxide (SiOx), etc.
[0085] According to exemplary embodiments, the common electrode 270
may be disposed on the microcavity 305 (as shown in the drawings)
or may be formed on a lower portion of the microcavity 305 to drive
the liquid crystal disposed in the microcavity 305 based on a
coplanar electrode (CE) mode.
[0086] A roof layer 360 is positioned on the lower insulating layer
350. The roof layer 360 serves to support the microcavity 305
defining a space between the pixel electrode 191 and the common
electrode 270. The roof layer 360 may include any suitable
material, such as, for example, silicon oxycarbide (SiOC), a
photoresist, and/or other organic materials.
[0087] When the roof layer 360 includes silicon oxycarbide (SiOC),
the roof layer 360 may be formed via a chemical vapor deposition
method. When the roof layer 360 includes the photoresist, the roof
layer 360 may be formed by a coating method. It is contemplated,
however, that any other suitable process may be utilized. It is
noted that silicon oxycarbide (SiOC) enables high transmittance and
strain does not occur because layer stresses are small among the
layers formed by, for example, the chemical vapor deposition
method. Accordingly, when the roof layer 360 is formed of silicon
oxycarbide (SiOC), a stable layer through which light passes well
may be formed.
[0088] An upper insulating layer 370 is positioned on the roof
layer 360. The upper insulating layer 370 may come into contact
with an upper surface of the roof layer 360. The upper insulating
layer 370 may be formed of any suitable material, such as, for
example, silicon nitride (SiNx), silicon oxide (SiOx), etc. A
capping layer 390 is positioned on the upper insulating layer 370.
The capping layer 390 comes into contact with an upper surface and
a lateral surface of the upper insulating layer 370. The capping
layer 390 covers the liquid crystal injection hole 307 of the
microcavity 305 exposed by the liquid crystal injection hole
forming region 307FP. The capping layer 390 may be formed of, for
example, a thermosetting resin, silicon oxycarbide (SiOC),
graphene, etc.
[0089] When the capping layer 390 is formed of graphene, since
graphene typically exhibits high permeation resistance to gas
including helium, and the like, the capping layer 390 may be
configured to cover the liquid crystal injection hole 307. Further,
since graphene is a material having a carbon bond, even though
graphene comes into contact with the liquid crystal material, the
liquid crystal material may not be contaminated. Moreover, graphene
may serve to protect the liquid crystal material with respect to
external contaminants, such as oxygen, moisture, debris, etc.
[0090] An overcoat layer (not illustrated) formed of an inorganic
layer or an organic layer may be positioned on the capping layer
390. The overcoat layer may serve to protect the liquid crystal
molecules 310 injected into the microcavity 305 from an external
impact, as well as planarize the layer capping layer 390.
[0091] According to exemplary embodiments, the liquid crystal
injection hole forming region 307FP is formed between the
microcavities 305 adjacent in a vertical direction. A light
blocking layer 500 covering the thin film transistor Q and the
contact hole 185 is formed in the liquid crystal injection hole
forming region 307FP. The light blocking layer 500 is formed of any
suitable material capable of reducing a leakage current of the thin
film transistor Q due to external light and blocking light in order
to prevent a reduction in a contrast ratio due to reflected light.
The light blocking layer 500 may be made of any suitable organic
material. The light blocking layer 500 may be formed of the same
material as the light blocking member 220. In exemplary
embodiments, the light blocking layer 500 may be formed in a
longitudinal extension direction of the gate line 121.
[0092] A first passivation layer 340 is positioned on a lower
portion of the light blocking layer 500. A common electrode portion
270a and a second passivation layer 350a are positioned on the
light blocking layer 500. In this manner, the first passivation
layer 340 and the second passivation layer 350a may be formed to
surround the light blocking layer 500 and configured to prevent the
light blocking layer 500 from being exposed to the outside. A
passivation layer including the first passivation layer 340 and the
second passivation layer 350a may be formed of any suitable
material, such as, for example, silicon nitride (SiNx), silicon
oxide (SiOx), etc.
[0093] According to exemplary embodiments, the first passivation
layer 340 may be formed in only the liquid crystal injection hole
forming region 307FP, and the second passivation layer 350a may be
formed at the same level as the lower insulating layer 350.
[0094] The capping layer 390 may cover the light blocking layer
500, as well as the liquid crystal injection hole 307. To this end,
the capping layer 390 may fill the liquid crystal injection hole
forming region 307FP between the microcavity 305 and the light
blocking layer 500.
[0095] According to exemplary embodiments, as illustrated in FIG.
3, a partition forming portion PWP is formed between the
microcavities 305 adjacent in a horizontal direction. The partition
forming portion PWP may be formed in a longitudinal extension
direction of the data line 171, and may be formed together with the
light blocking layer 500, such as simultaneously formed with the
light blocking layer 500. Accordingly, the partition forming
portion PWP may be made of the same material as the light blocking
layer 500.
[0096] A polarizer (not illustrated) may be positioned on a lower
portion of the insulation substrate 110 and an upper portion of the
upper insulating layer 370. The polarizer may include a
polarization element generating polarization and a TAC
(tri-acetyl-cellulose) layer for ensuring durability. Directions of
transmissive axes of an upper polarizer and a lower polarizer may
be vertical or parallel according to exemplary embodiments.
[0097] While certain exemplary embodiments and implementations have
been described herein, other embodiments and modifications will be
apparent from this description. Accordingly, the invention is not
limited to such embodiments, but rather to the broader scope of the
presented claims and various obvious modifications and equivalent
arrangements.
* * * * *