Liquid crystal display having sensor and spacer arrangement and and method of manufacturing the same

A liquid crystal display (“LCD”) includes: a first substrate; a sensor pad disposed on the first substrate; a second substrate which faces the first substrate; a sensor spacer and a supporting spacer disposed on the second substrate; and a supporting dielectric portion disposed between the supporting spacer and the first substrate. The sensor spacer is spaced apart from the sensor pad, and includes a sensor electrode disposed on a portion of the sensor spacer which faces the sensor pad. The supporting spacer is spaced apart from the first substrate, and the supporting dielectric portion uniformly maintains a cell gap between the first substrate and the second substrate.

This application claims priority to Korean Patent Application No. 10-2008-0005064, filed on Jan. 16, 2008, and all the benefits accruing therefrom under 35 U.S.C. §119, the contents of which in its entirety are herein incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a liquid crystal display (“LCD”) and a method of manufacturing the LCD, and more particularly, to an LCD having substantially improved operating reliability and durability and a method of manufacturing the LCD.

2. Description of the Related Art

Touch screen display devices are a type of advanced input device which can replace existing input devices such as a keyboards or a mouse, for example. Touch screen display devices typically include a touch screen mounted on a liquid crystal panel, and perform operations in response to a touch input on the liquid crystal panel. Touch screen display devices are suitable for allowing various tasks to be easily performed in a graphic user interface (“GUI”) environment such as in a MICROSOFT WINDOWS® operating system (“OS”) environment, and thus can be widely used in fields of computer-based training and simulation applications, office automation applications, education applications and game applications, for example.

A typical touch screen includes a liquid crystal panel for displaying images, a touch panel attached to the liquid crystal panel, a controller, a device driving module and an application program.

The combination of a touch screen display device and a liquid crystal display (“LCD”) has been widely used in various portable devices such as a personal digital assistant (“PDA”) or a mobile phone, for example.

In general, when a user touches or slightly presses a certain portion on the touch screen display device with their finger or a pen, for example, electrically connected upper and lower conductive layers of the touch screen display device detect a position corresponding to the pressed portion on the touch screen display device.

Thus, it is desirable for the touch screen device to have a high operating reliability and durability when repeatedly exposed to external pressure, or when used for an extended period of time.

BRIEF SUMMARY OF THE INVENTION

An exemplary embodiment of the present invention provides a liquid crystal display (“LCD”) having substantially improved operating reliability and durability.

An exemplary embodiment of the present invention also provides a method of manufacturing the LCD having substantially improved operating reliability and durability.

According to an exemplary embodiment of the present invention, an LCD includes: a first substrate; a sensor pad disposed on the first substrate; a second substrate which faces the first substrate; a sensor spacer disposed on the second substrate; a supporting spacer disposed on the second substrate; and a supporting dielectric portion disposed between the supporting spacer and the first substrate. The sensor spacer is spaced apart from the sensor pad, and comprises a sensor electrode disposed on a portion of the sensor spacer which faces the sensor pad. The supporting spacer is spaced apart from the first substrate, and the supporting dielectric portion uniformly maintains a cell gap between the first substrate and the second substrate.

According to an alternative exemplary embodiment of the present invention, a method of manufacturing an LCD includes: forming a black matrix on an insulating substrate; forming a sensor spacer on the black matrix; forming a supporting spacer on the black matrix; forming an electrode on the sensor spacer and the supporting spacer; and forming a supporting dielectric portion on the supporting spacer.

DETAILED DESCRIPTION OF THE INVENTION

Furthermore, relative terms, such as “lower” or “bottom” and “upper” or “top” may be used herein to describe one element's relationship to other elements as illustrated in the Figures. It will be understood that relative terms are intended to encompass different orientations of the device in addition to the orientation depicted in the Figures. For example, if the device in one of the figures is turned over, elements described as being on the “lower” side of other elements would then be oriented on the “upper” side of the other elements. The exemplary term “lower” can, therefore, encompass both an orientation of “lower” and “upper,” depending upon the particular orientation of the figure. Similarly, if the device in one of the figures were turned over, elements described as “below” or “beneath” other elements would then be oriented “above” the other elements. The exemplary terms “below” or “beneath” can, therefore, encompass both an orientation of above and below.

A liquid crystal display (“LCD”) according to an exemplary embodiment of the present invention will hereinafter be described in further detail with reference toFIGS. 1 through 2C.

FIG. 1is a layout view of an LCD according to an exemplary embodiment of the present invention,FIG. 2Ais a partial cross-sectional view taken along line IIa-IIa′ ofFIG. 1,FIG. 2Bis a partial cross-sectional view taken along lines IIb-IIb′ and IIb″-IIb″ ofFIG. 1, andFIG. 2Cis a schematic layout view of an arrangement of a plurality of sensor spacers, a plurality of supporting spacers and a plurality of auxiliary spacers in the LCD according to the exemplary embodiment of the present invention shown inFIG. 1.

An LCD1according to an exemplary embodiment of the present invention includes a lower display panel100which includes a thin-film transistor (“TFT”), an upper display panel200which faces the lower display panel100and includes a common electrode150, and a liquid crystal layer300interposed between the lower display panel100and the upper display panel200. In an exemplary embodiment, the TFT is defined by a gate line22and a data line62.

The lower display panel100will hereinafter be described in further detail. In an exemplary embodiment, the gate line22and a gate electrode26are formed on a first substrate10. The gate line22extends in a first direction, e.g., a substantially row, or horizontal, direction as viewed inFIG. 1. The gate electrode26extends from the gate line22, e.g., the gate electrode26is a protrusion from the gate line22. The gate line22and the gate electrode26will hereinafter be collectively referred to as “gate wiring”.

A first sensor electrode line28and a first sensor electrode29are formed on the first substrate10. The first sensor electrode line28extends in the first direction, e.g., substantially parallel to the gate line22, as shown inFIG. 1. The first sensor electrode29extends from the first sensor electrode line28, e.g., as a protrusion thereof, along a second direction substantially perpendicular to the first direction. In an exemplary embodiment of the present invention, the first sensor electrode29is a terminal of a touch screen sensor (not shown) and is connected to a first sensor pad84through a contact hole72. When external pressure is applied, e.g., from a user touching the touch screen sensor, the first sensor electrode29is electrically connected to a sensor electrode151, which is formed on a sensor spacer140, and position information, indicating a point at which the external pressure is applied, is thereby provided by the sensor electrode151. The first sensor electrode29and the first sensor electrode line28will hereinafter be collectively referred to as “first sensor wiring”.

In an exemplary embodiment, the gate wiring and the first sensor wiring are formed of an aluminum-based metal such as aluminum (Al) or an aluminum alloy, a silver-based metal such as silver (Ag) or a silver alloy, a copper-based metal such as copper (Cu) or a copper alloy, a molybdenum-based metal such as molybdenum (Mo) or a molybdenum alloy, chromium (Cr), titanium (Ti) or tantalum (Ta), for example, but alternative exemplary embodiments are not limited thereto. Further, the gate wiring and the first sensor wiring may have a multilayer structure including two conductive layers (not shown) having different physical properties. More specifically, the gate wiring and the first sensor wiring in an exemplary embodiment may include a first conductive layer, formed of a metal having low resistivity, such as an aluminum-based metal, a silver-based metal or a copper-based metal, thereby reducing signal delays and voltage drops in the gate wiring and the first sensor wiring, and a second conductive layer formed of a material having excellent bonding properties with indium tin oxide (“ITO”) and indium zinc oxide (“IZO”), such as a molybdenum-based material, chromium, titanium or tantalum. For example, the gate wiring and the first sensor wiring in an exemplary embodiment may include a chromium lower layer and an aluminum upper layer or, alternatively, an aluminum lower layer and a molybdenum upper layer. However, alternative exemplary embodiments of the present invention are not limited or restricted to the abovementioned configurations. For example, the gate wiring and the first sensor wiring of alternative exemplary embodiments may include various materials and conductive materials other than those listed and/or described herein.

A gate insulation layer30is formed of silicon nitride (“SiNx”), for example, on the gate wiring and the first sensor wiring. A semiconductor layer40is formed of hydrogenated amorphous silicon (“a-Si”) or polycrystalline silicon (“p-Si”), for example, on the gate insulation layer30. In an exemplary embodiment, the semiconductor layer40is formed in various shapes, such as an island shape, e.g., a rectilinear shape, or a linear shape, for example. More specifically, the semiconductor layer40may be formed as an island on the gate electrode26, as shown inFIG. 1. Alternatively, the semiconductor layer40may be formed below the data line62as a line which extends over the gate electrode26(not shown). When the semiconductor layer40is formed as a line, the semiconductor layer40may be formed by being patterned in substantially the same manner as for the data line62.

Ohmic contact layers55and56are formed on the semiconductor layer40and may include silicide or n+ hydrogenated amorphous silicon doped with a high concentration of n-type impurities. The ohmic contact layers55and56may be formed in various shapes such as an island shape, e.g., a substantially rectilinear shape, or a linear shape. For example, the ohmic contact layers55and56may be formed as islands below a source electrode65and a drain electrode66, respectively, as shown inFIG. 2A. When the ohmic contact layers55and56are formed as islands, the ohmic contact layers55and56may be disposed below the source electrode55and the drain electrode66. Alternatively, when the ohmic contact layers55and56are formed as lines, the ohmic contact layers55and56may extend below the data line62(not shown).

The data line62and the drain electrode66are formed on the ohmic contact layers55and56and the gate insulating layer30. The data line62extends in the second direction, e.g., a substantially column direction inFIG. 1, and intersects the gate line22. The source electrode65is formed as a branch, e.g., a protrusion, of the data line62and extends over a portion of the semiconductor layer40, as shown inFIG. 2A. Further, the drain electrode66is spaced apart from the source electrode65. In addition, the drain electrode66and the source electrode65are disposed on substantially opposite sides of the gate electrode26and are formed on the semiconductor layer40, as shown inFIG. 2A. The TFT, defined in an exemplary embodiment by the gate line22and the data line62, is a three terminal device including the gate electrode26, the source electrode65and the drain electrode66. A current flows between the source electrode65and the drain electrode66when an appropriate voltage is applied to the gate electrode26.

In an exemplary embodiment, the drain electrode66has a substantially bar-shaped pattern which extends over the semiconductor layer40, and a drain electrode extension portion67which extends from the bar-shaped pattern as shown inFIGS. 1 and 2A. The drain electrode extension portion67has a wider area than an area of the bar-shaped pattern, and includes a contact hole78formed therein, as further shown inFIGS. 1 and 2A.

The data line62, the source electrode65, the drain electrode66and the drain electrode extension portion67will hereinafter be collectively referred to as “data wiring”.

A second sensor electrode line61and a second sensor electrode63are formed on the gate insulation layer30. The second sensor electrode line61is spaced apart from the data line62and extends in substantially the second direction. The second sensor electrode63extends from the second sensor electrode line61, e.g., as a protrusion therefrom, and therefore has a width, as measured along the first direction, which is greater than a width of the second sensor electrode line61measured along the first direction. The second sensor electrode63according to an exemplary embodiment of the present invention is a terminal of a touch screen sensor (not shown) and is connected to a second sensor pad85through a contact hole73. When external pressure is applied, e.g., by a user pressing the touch screen sensor, the second sensor electrode63is electrically connected to the sensor electrode151and thereby provides position information indicating a point at which the external pressure is applied. The second sensor electrode63and the second sensor electrode line61will hereinafter be collectively referred to as “second sensor wiring”. In an exemplary embodiment, the first sensor wiring provides row-direction coordinate data of the position at which external pressure is applied, and the second sensor wiring provides column-direction coordinate data of the position at which external pressure is applied.

In an exemplary embodiment of the present invention, the data wiring and the second sensor wiring include a single layer structure or, alternatively, a multilayer structure including at least one of aluminum, chromium, molybdenum, tantalum and titanium, for example. Further, the data wiring and the second sensor wiring according to an exemplary embodiment may be formed of a fire-resistant metal such as a molybdenum-based metal, tantalum or titanium, but alternative exemplary embodiments are not limited thereto. The data wiring and the second sensor wiring may further include a lower layer formed of a fire-resistant metal, and an upper layer formed of a low-resistance material. For example, the data wiring and the second sensor wiring according to an exemplary embodiment include a double layer having a chromium lower layer and an aluminum upper layer or, in an alternative exemplary embodiment, an aluminum lower layer and a molybdenum upper layer. Yet another alternative exemplary embodiment of the present invention may include a triple layer having a molybdenum layer, an aluminum layer and a molybdenum layer.

The source electrode65overlaps at least a first portion the semiconductor layer40, as shown inFIG. 2A. Further, the drain electrode66and the source electrode65are disposed on opposite sides of the gate electrode26. The drain electrode66overlaps at least a second portion of the semiconductor layer40. Further, the ohmic contact layer55is interposed between the source electrode65and the semiconductor layer40, and the ohmic contact layer56is interposed between the drain electrode66and the semiconductor layer40, as shown inFIG. 2A. Thus, the ohmic contact layers55and56reduce a contact resistance between the semiconductor layer40and the source electrode65and between the semiconductor layer40and the drain electrode66, respectively.

A passivation layer70is formed of a dielectric material on the data wiring, the second sensor wiring, and an exposed portion of the semiconductor layer40. in an exemplary embodiment, the passivation layer70is formed of an inorganic material such as silicon nitride or silicon oxide, an organic material having excellent planarization properties and photosensitivity, or a low-k dielectric material such as a-Si:C:O or a-Si:O:F formed by plasma enhanced chemical vapor deposition (“PECVD”), but alternative exemplary embodiments are not limited to the foregoing description. Further, when the passivation layer70is formed of an organic layer, the passivation layer70may be formed as a double layer having a lower inorganic layer formed of silicon nitride (“SiNx”) or silicon oxide (“SiO2”) and an upper organic layer, in order to prevent the exposed portion of the semiconductor layer40from directly contacting the organic material. The passivation layer70may be formed of a thin inorganic material to improve a reliability of contact between the sensor spacer140and the first sensor pad84, and between the sensor spacer140and the second sensor pad85.

The contact hole73and the contact hole78are formed through the passivation layer70. The contact holes73and78expose the second sensor electrode63and the drain electrode extension portion67, respectively. In addition, the contact hole72is formed through the passivation layer70and the gate insulation layer30and thereby exposes the first sensor electrode29, as shown inFIG. 1.

A pixel electrode82is formed on the passivation layer70, conforming to the shape of a pixel. The pixel electrode82is electrically connected to the drain electrode66through the contact hole78. The pixel electrode82, together with the common electrode150of the upper display panel200, generates an electric field therebetween, and thus aligns liquid crystal molecules in the liquid crystal layer300, disposed between the pixel electrode82and the common electrode150, to thereby display an image with the LCD1according to an exemplary embodiment of the present invention.

The first sensor pad84and the second sensor pad85are formed on the passivation layer70. The first sensor pad84is connected to the first sensor electrode29through the contact hole72, and the second sensor pad85is connected to the second sensor electrode63through the contact hole73. In an exemplary embodiment, the pixel electrode82, the first sensor pad84and the second sensor pad85are formed of a transparent conductive material such as ITO or IZO, or a reflective conductive material such as aluminum, but alternative exemplary embodiments are not limited thereto.

The first sensor pad84and the second sensor pad85are disposed on a level with each other and spaced apart from each other. The first sensor pad84, the second sensor pad85and the sensor electrode151form a switching device. Specifically, the first sensor pad84and the second sensor pad85, which are spaced apart from each other, are electrically connected to each other via the sensor electrode151, and thus recognize the position of the sensor spacer140. An operation of the LCD1will be described below in further detail. The first sensor pad84and the second sensor pad85according to an exemplary embodiment may be laid over a black matrix120of the upper display panel200(seeFIGS. 2A and 2B).

A supporter89, e.g., a supporting portion89may be disposed on the lower display panel100. The supporting portion89supports a supporting spacer142. The supporting portion89may be formed to the same height as the first sensor pad84and the second sensor pad85. In addition, the supporting portion89may be formed of the same material as the first sensor pad84and the second sensor pad85. The supporting portion89is optional, e.g., the supporting portion89may be omitted from alternative exemplary embodiment s of the present invention. In this case, the passivation layer70performs a function of the supporting portion89.

In an exemplary embodiment, an alignment layer (not shown) which aligns the liquid crystal layer300is formed on the pixel electrode82, the first sensor pad84, the second sensor pad85and the passivation layer70.

Still referring toFIGS. 1 through 2C, the upper display panel200will hereinafter be described in further detail. The black matrix120is formed on a second substrate110, which is formed of a transparent dielectric material such as glass, for example, but not being limited thereto. In an exemplary embodiment, the black matrix120overlaps the gate line22, the data line62and the TFT. The black matrix120may be formed of a metal such as chromium, a metal oxide such as chromium oxide, or organic black resist, for example, but alternative exemplary embodiments are not limited thereto.

In an exemplary embodiment, a color filter130such as a red, green or blue filter may be arranged in a pixel region substantially defined by the black matrix120. An overcoat layer (not shown) may be formed on the color filter130to planarize the color filter130.

The sensor spacer140is formed on the black matrix120. The sensor spacer140may be formed of a photosensitive resin, for example. Further, the sensor spacer140may be formed with the color filter130. The sensor spacer140protrudes downward, e.g., from the upper display panel200toward the lower display panel100, as shown inFIG. 2B. In addition, the sensor spacer140overlaps at least a portion of each of the first sensor pad84and the second sensor pad85. In an exemplary embodiment, the sensor spacer140is disposed at a predetermined distance from the first sensor pad84and the second senor pad85, and is thus electrically isolated from the first sensor pad84and the second sensor pad85. In an alternative exemplary embodiment of the present invention, the sensor spacer140may be substantially laid over the black matrix120, instead of being laid over the pixel electrode82, to prevent a reduction in an aperture ratio of each pixel of the LCD1.

In an exemplary embodiment, the sensor spacer140is formed between adjacent blue color filters B, as shown inFIG. 2C.

The LCD1according to an exemplary embodiment of the present invention displays an image by mixing red light, green light and blue light emitted from red, green and blue color filters130, respectively. An influence of blue light on a luminance of the LCD1is less than an influence of red light or green light on the luminance of the LCD1. Thus, when the sensor spacer140is disposed over a portion of a blue color filter230, the aperture ratio of the LCD1is not substantially reduced.

The sensor electrode151is formed on the sensor spacer140, as shown inFIG. 2B. Further, the sensor electrode151may overlap at least a portion of both the first sensor pad84and the second sensor pad85. Alternatively, the sensor electrode151may be disposed on an entire surface of the sensor spacer140(not shown). In an exemplary embodiment, the sensor electrode151is formed of substantially the same material as the common electrode150. Specifically, the sensor electrode151may be formed as substantially one body including the common electrode150. Alternatively, the sensor electrode151may be formed only on the sensor spacer140. In this case, the sensor electrode151may electrically connect the first sensor pad84and the second sensor pad85by receiving a signal from one of the first sensor pad84and the second sensor pad85and outputting the received signal to the other sensor pad of the one of the first sensor pad84and the second sensor pad85.

The upper display panel200according to an exemplary embodiment of the present invention further includes the supporting spacer142, which is spaced apart from the sensor spacer140, as shown inFIGS. 1 and 2B. The supporting spacer142maintains a cell gap between adjacent a liquid crystal panels of the LCD1. Further, a supporting dielectric portion160is formed on the supporting spacer142. In an exemplary embodiment, the supporting spacer142is formed to have a substantially same height as a height of the sensor spacer140, relative to a surface of the upper display panel200, by using a common method to form the sensor spacer140and the supporting spacer142. As a result, a cell gap is uniformly maintained between the liquid crystal panels, and a reliability of the LCD1is thereby substantially improved in an exemplary embodiment of the present invention.

In addition, since the supporting spacer142is formed using the same method which is used to form the sensor spacer140, the common electrode150extends over at least a portion of the supporting spacer142. Thus, a distance between the supporting spacer142and the supporting portion89is maintained to be substantially the same as a distance between the sensor spacer140and each of the first sensor pad84and the second sensor pad85.

The supporting dielectric portion160is interposed between the supporting spacer142and the supporting portion89, as shown inFIG. 2B. The supporting dielectric portion160electrically isolates the supporting spacer142from the supporting portion89, and, along with the supporting portion89, uniformly adjusts a distance between the sensor electrode151and each of the first sensor pad84and the second sensor pad85, thereby preventing the distance between the sensor spacer140and each of the first sensor pads84and the second sensor pad85from becoming irregular, e.g., uneven, due to drift, e.g., variations in a production process, or through use of the LCD1according to an exemplary embodiment, for example.

In an exemplary embodiment, the supporting spacer142is formed on the black matrix120. A distance between adjacent supporting spacers142is determined based on a desired feel of a touch between the sensor spacer140and each of the first sensor pad84and the second sensor pad85.

To maintain the uniform cell gap of the liquid crystal panel and to protect the sensor spacer140and/or each of the first sensor pad84and the second sensor pad85when an excessive pressure is applied to the upper display panel200, for example, the upper display panel200according to an exemplary embodiment further includes an auxiliary spacer141. The auxiliary spacer141is formed on the black matrix120, is disposed a predetermined distance apart from the sensor spacer140, and protrudes toward the lower display panel100, e.g., downward as shown inFIG. 2B. In an exemplary embodiment, the auxiliary spacer141may be with the supporting dielectric portion160. A distance between the auxiliary spacer141and the lower display panel100may be greater than the distance between the sensor spacer140and each of the first sensor pad84and the second sensor pad85. As a result, when a standard, e.g., non-excessive, pressure is applied to the upper display panel200, the sensor spacer140contacts the first sensor pad84and the second sensor pad85, whereas the auxiliary spacer141does not contact the lower display panel100. On the other hand, when pressure higher than the standard pressure, e.g., an excessive pressure, is applied to the upper display panel200, the sensor spacer140contacts the first sensor pad84and the second sensor pad85, while the auxiliary spacer141contacts the lower display panel100, thus further supporting the upper display panel200and thereby effectively preventing deformation of the upper display panel200of the LCD1according to an exemplary embodiment of the present invention.

The common electrode150according to an exemplary embodiment is formed of a transparent conductive material such as ITO or IZO, for example, on the black matrix120, the color filter130and the sensor spacer140.

An alignment layer (not shown) which aligns the liquid crystal molecules of the liquid crystal layer may be formed on the common electrode150in an alternative exemplary embodiment of the present invention.

As described in further detail above, the sensor spacer140is separate from the lower display panel100at an initial state, i.e., when no external pressure is applied. On the other hand, when an external pressure is applied, the common electrode150on the sensor spacer140contacts the first sensor pad84and the second sensor pad85and is thus electrically connected to the first sensor pad84and the second sensor pad85, thereby recognizing a point at which the external pressure is applied.

An arrangement of the sensor spacer140, the supporting spacer142and the auxiliary spacer141will hereinafter be described in further detail with reference toFIG. 2C.

Referring toFIG. 2C, pixels of a plurality of pixels according to an exemplary embodiment of the present invention are defined by gate lines22of a plurality of the gate lines22and data lines62of a plurality of the data lines62which intersect the gate lines22. Specifically, red pixels R, green pixels G and blue pixels B are alternately arranged, as shown inFIG. 2C. A set of three pixels, e.g., a set including a red pixel R, a green pixel G and a blue pixel B is a dot. Thus, in an exemplary embodiment, a dot is defined as a pixel region including a pixel R, a green pixel G and a blue pixel B.

To precisely recognize application of an external pressure, a sensor spacer140is provided for each dot. A density of sensor spacers140in the LCD1according to alternative exemplary embodiments of the present invention may be adjusted based on a size of a liquid crystal panel and/or a size of pixels, for example. As described above, the sensor spacer140is formed between a pair of adjacent B pixels in an exemplary embodiment. The density of sensor spacers140in the LCD1affects a precision of determination of a touch position, e.g., a position at which the external pressure is applied.

In an exemplary embodiment, a supporting spacer142may be provided each 250 dots.

The density of supporting spacers142in the LCD1also affects a feel of a touch when applying the external pressure thereto. Specifically, an increase in the density of supporting spacers142in the LCD1results in an adverse feel when applying the external pressure, e.g., when touching the LCD1. Thus, in an exemplary embodiment, the supporting spacers142are provided each 250 dots or, alternatively, each 300 dots. In addition, a plurality of the supporting spacers142is uniformly distributed in the LCD1according to an exemplary embodiment of the present invention.

Further, as described in greater detail above, the auxiliary spacer141may be formed near the sensor spacer140to effectively prevent an excessive pressure from being applied to the sensor spacer140. In an exemplary embodiment, two auxiliary spacers141may be provided for each dot. Specifically, in an exemplary embodiment wherein the sensor spacer140is provided in a blue pixel B a given dot, two auxiliary spacers141may be provided in the corresponding red pixel R and the green pixel G pixels of the given dot.

The sensor spacer140, the supporting spacer142and the auxiliary spacer141may be disposed over at least a portion of the black matrix120between adjacent pixels. Positions of the sensor spacer140, the supporting spacer142and the auxiliary spacer141may be altered, however, based on a desired feel of touch and/or a precision of determination of a touch point in the LCD1according to alternative exemplary embodiments of the present invention.

An operation of the LCD1according to the exemplary embodiment of the present invention shown inFIG. 1will hereinafter be described in further detail with reference toFIGS. 3A through 3C.FIGS. 3A through 3Care partial cross-sectional views for explaining the operation of the LCD1according to the exemplary embodiment of the present invention shown inFIG. 1.

More specifically,FIG. 3Ais a partial cross-sectional view which illustrates the LCD1in an initial state, e.g., when external pressure is not applied to the upper display panel200. Referring toFIG. 3A, the lower display panel100and the upper display panel200are substantially parallel to each other, the sensor spacer140is a predetermined distance T1from the first sensor pad84and the second sensor pad85, and the first sensor pad84and the second sensor pad85are electrically isolated from each other. The distance T1is substantially the same as a thickness T3of the supporting dielectric portion160.

The auxiliary spacer141is a predetermined distance T2from the lower display panel100. In an exemplary embodiment, the predetermined distance T2is greater than the predetermined distance T1.

FIG. 3Bis a partial cross-sectional view which illustrates the LCD1when a normal pressure Pn is applied to the upper display panel200. Referring toFIG. 3B, when the normal pressure Pn is applied to the upper display panel200, the upper display panel200bends downward, e.g., toward the lower display panel100, and the sensor electrode151of the sensor spacer140thereby contacts the first sensor pad84and the second sensor pad85. As a result, the first sensor pad84and the second sensor pad85are electrically connected, and a position of the sensor spacer140is thereby recognized.

In this case, the auxiliary spacer141does not contact the lower display panel100, and thus, the distance between the auxiliary spacer141and the lower display panel100is uniformly maintained. Therefore, no external pressure is applied to the auxiliary spacer141.

FIG. 3Cis a partial cross-sectional view which illustrates the LCD1when excessive pressure Pe is applied to the upper display panel200. Referring toFIG. 3C, when the excessive pressure Pe is applied to the supporting spacer142and the sensor spacer140when the sensor electrode151contacts the first sensor pad84and the second sensor pad85, the sensor spacer140, the sensor electrode151, the first sensor pad84and the second sensor pad85may be damaged. In order to prevent this, the auxiliary spacer141is provided in the LCD1according to an exemplary embodiment of the present invention. The auxiliary spacer141supports the upper display panel200while the excessive pressure Pe is applied to the upper display panel200. More specifically, when the excessive pressure Pe is applied, the auxiliary display panel100contacts the lower display panel100, and thus effectively maintains the cell gap between the lower display panel100and the upper display panel200. Therefore, the auxiliary spacer141disperses the external pressure Pe applied to the upper display panel200to supports the upper display panel200, thereby effectively preventing damage to the LCD1according to an exemplary embodiment of the present invention.

A manufacturing method of the upper display panel200according to an exemplary embodiment of the present invention will hereinafter be described in further detail with reference toFIGS. 4A through 4E.FIGS. 4A through 4Eare partial cross-sectional views for explaining a manufacturing method of the upper display panel200of the LCD1according to an exemplary embodiment of the present invention. The same labels inFIGS. 4A through 4Ewill be used to designate the same or like components as described above, and any repetitive detailed description thereof will hereinafter be omitted.

Referring toFIG. 4A, a light shield layer (not shown) for forming a black matrix120is formed on a first substrate110. Thereafter, the black matrix120is formed by etching the light shield layer using a photoresist pattern (not shown) as an etching mask.

Thereafter, referring toFIG. 4B, a pixel region is defined by patterning the black matrix120. Next, a color filter130, such as a red color filter, a green color filter or a blue color filter, is formed in the pixel region.

Thereafter, referring toFIG. 4C, a photosensitive resin layer (not shown) is formed on substantially an entire exposed surface of the first substrate110. Next, a sensor spacer140and a supporting spacer142are formed by performing an exposure and a development of the photosensitive resin layer and thereby patterning the photosensitive resin layer. To increase an aperture ratio of an LCD1according to an exemplary embodiment of the present invention, the sensor spacer140and the supporting spacer142are disposed on the black matrix120. As described above in greater detail, a sensor spacer140may be provided for each dot, and two supporting spacers142may be provided for each dot.

Referring now toFIG. 4D, a common electrode150, having a uniform thickness thereof, is next formed. A portion of the common electrode150disposed on the sensor spacer140may become a sensor electrode151.

Next, referring toFIG. 4E, an organic layer (not shown) is formed on the common electrode150. Thereafter, a supporting dielectric portion160and an auxiliary spacer141are formed by patterning the organic layer. The supporting dielectric portion160is formed on the supporting spacer142, and the auxiliary spacer141is disposed over the black matrix120. In an exemplary embodiment, two auxiliary spacers141may be provided for each dot. Further, the auxiliary spacer141may be formed in a pixel in which no sensor spacer140is formed. In an alternative exemplary embodiment, however, a position of the auxiliary spacer141may be altered. Further, the supporting dielectric portion160and the auxiliary spacer141may be formed together by using substantially the same method. A height of the auxiliary spacer141is adjusted by using a slit mask or a half mask, for example.

Thus, the upper display panel200is thereby manufactured according to an exemplary embodiment of the present invention. The upper display panel200is then disposed to substantially face a lower display panel100(FIGS. 2A through 2C), and a liquid crystal layer300is interposed between the upper display panel200and the lower display panel100. Since the supporting spacer142and the supporting dielectric portion160support both the upper display panel200and the lower display panel100, a cell gap between the upper display panel200and the lower display panel100are uniformly maintained in the LCD1according to an exemplary embodiment of the present invention. In an exemplary embodiment, the sensor spacer140and the auxiliary spacer141are both spaced apart from the lower display panel100. Further, a distance between the auxiliary spacer141and the lower display panel100is greater than a distance between the sensor spacer140and the lower display panel100in the LCD1according to an exemplary embodiment of the present invention.

An LCD according to an alternative exemplary embodiment of the present invention will hereinafter be described in further detail with reference toFIGS. 5 and 6.FIG. 5is a layout view of an LCD1′ according to an alternative exemplary embodiment of the present invention, andFIG. 6is a partial cross-sectional view taken along lines VI-VI′ and VI″-VI′″ ofFIG. 5. InFIGS. 1 through 6, the same reference numerals indicate the same or like elements as described above, and any repetitive detailed description thereof will hereinafter be omitted.

Referring toFIGS. 5 and 6, a first supporting protrusions261and a second supporting protrusion262are formed on opposite sides of a sensor spacer240.

As shown inFIG. 6, a bottom portion of the sensor spacer240has a step difference, e.g., a thickness of the sensor spacer240between an upper display panel200′ and a lower display panel100′ is not uniform. Specifically, a sensor electrode251is formed on a first portion of the bottom portion of the sensor spacer240. In an exemplary embodiment, the sensor electrode251is part of a common electrode formed on an entire surface of the upper display panel200′. Further, the sensor electrode251may be disposed to be in contact with a first sensor pad284and a second sensor pad285and may thus electrically connect the first sensor pad284and the second sensor pad285. The first supporting protrusion261and the second supporting protrusion262protect the sensor spacer240, the first pad284and the second sensor pad285when excessive pressure is applied to the sensor spacer240.

In an exemplary embodiment, a predetermined distance T1′ between the lower display panel100′ and the first supporting protrusion261and the second supporting protrusion262is greater than a distance between the sensor electrode251and each of the first sensor pad284and the second sensor pad285. In an alternative exemplary embodiment, the first supporting protrusion261and the second supporting protrusion262are not formed on opposite sides of the sensor spacer240. For example, the first supporting protrusion261and the second supporting protrusion262may be formed on one side, e.g., a same side, of the sensor spacer240. The first supporting protrusion261and the second supporting protrusion262may also be formed of one body with the sensor spacer240. Further, the first supporting protrusion261and the second supporting protrusion262may be formed on the sensor spacer240by using an inkjet firing method, for example, but alternative exemplary embodiments are not limited thereto.

An operation of the LCD1′ according to an exemplary embodiment of the present invention will hereinafter be described in further detail with reference toFIGS. 7A through 7C.FIGS. 7A through 7Care partial cross-sectional views for explaining an operation of the LCD1′ according to an exemplary embodiment of the present invention.

FIG. 7Ais a partial cross-sectional view showing the LCD1′ in an initial state, e.g., when external pressure is not applied to the upper display panel200′. Referring toFIG. 7A, the lower display panel100′ and the upper display panel200′ are substantially parallel to each other, the sensor spacer240is a predetermined distance T1′ from the first sensor pad284and the second sensor pad285, and the first sensor pad284and the second sensor pad285are electrically isolated from each other. In an exemplary embodiment, the predetermined distance T1′ is substantially the same as a thickness T3′ of the supporting dielectric portion160.

The first supporting protrusion261and the second supporting protrusion262are a predetermined distance T2′ apart from the lower display panel100′. In an exemplary embodiment, the predetermined distance T2′ is greater than the predetermined distance T1′

FIG. 7Bis a partial cross-sectional view showing the LCD1′ when a normal pressure Pn is applied to the upper display panel200′. Referring toFIG. 7B, when the normal pressure Pn is applied to the upper display panel200′, the upper display panel200′ bends downward, e.g., toward the lower display panel100′, and the sensor electrode251thereby contacts the first sensor pad284and the second sensor pad285. Then, the first sensor pad284and the second sensor pad285are electrically connected, and a position of the sensor spacer240is thereby recognized.

In this case, the first supporting protrusion261and the second supporting protrusion262do not contact the lower display panel100′, and the a distance between the lower display panel100′ and the first supporting protrusion261and the second supporting protrusion262is thereby uniformly maintained. Therefore, no external pressure is applied to the first supporting protrusion261or the second supporting protrusion262.

FIG. 7Cis a partial cross-sectional view showing the LCD1′ when an excessive pressure Pe is applied to the upper display panel200′. Referring toFIG. 7C, when the excessive pressure Pe is applied to the supporting spacer142and the sensor spacer240when the sensor electrode251already contacts the first sensor pad84and the second sensor pad85, the sensor spacer240, the sensor electrode251, the first sensor pad284and the second sensor pad285may be damaged. In order to prevent this, the first supporting protrusion261and the second supporting protrusion262are provided in the LCD1′ according to an exemplary embodiment of the present invention. The first supporting protrusion261and the second supporting protrusion262support the upper display panel200′ while the excessive pressure Pe is applied to the upper display panel200′. More specifically, when the excessive pressure Pe is applied, the first supporting protrusion261and the second supporting protrusion262contact the lower display panel100′, and thus maintain a cell gap between the lower display panel100′ and the upper display panel200′. As a result, the first supporting protrusion261and the second supporting protrusion262disperse the excessive pressure Pe applied to the upper display panel200′, and support the upper display panel200′, thereby effectively preventing damage to the LCD1′ according to an exemplary embodiment of the present invention.

An LCD according to yet another alternative exemplary embodiment of the present invention will hereinafter be described in further detail with reference toFIG. 8.FIG. 8is a partial cross-sectional view of an LCD1″ according to an alternative exemplary embodiment of the present invention. InFIGS. 1 through 4and8, the same reference numerals indicate the same or like elements, as described above, and any repetitive detailed description thereof will hereinafter be omitted.

Referring toFIG. 8, a color filter75, such as a red, green or blue color filter75, is formed in a pixel region on a first substrate10. More specifically, a gate electrode26, a gate insulation layer30, a source electrode65and a drain electrode66are formed on the first substrate10, and the color filter75is also formed on the first substrate10.

A passivation layer70is formed on the color filter. A contact hole78is formed through the passivation layer70such that he drain electrode66is at least partially exposed through the passivation layer70via the contact hole78.

A pixel electrode82is formed of a transparent conductive material such as ITO or IZO, for example, on the passivation layer70. The pixel electrode82for each pixel is isolated, and is electrically connected to a respective drain electrode66through a corresponding contact hole78.

The pixel electrode82, together with the common electrode150of an upper display panel200″, generates an electric field therebetween, and thus aligns liquid crystal molecules in the liquid crystal layer300, disposed between the pixel electrode82and the common electrode150, to thereby display an image using the LCD1″ according to an exemplary embodiment of the present invention.

Thus, according to exemplary embodiments of the present invention as described herein, an LCD has at least the advantages of substantially increased operating reliability and durability.