This application claims priority from and the benefit of Korean Patent Application No. 10-2015-0103876, filed on Jul. 22, 2015, which is hereby incorporated by reference for all purposes as if fully set forth herein.
Field
Exemplary embodiments relate to a display device.
Discussion
Liquid crystal display (LCD) devices are widely used, and typically include two display panels with a liquid crystal (LC) layer disposed therebetween. The two display panels may include electric field-generating electrodes, such as a pixel electrode and a common electrode. The LCD device may generate an electric field in the LC layer by applying a voltage to the electric field-generating electrodes. The generation of the electric field may control the alignment of LC molecules of the LC layer. The controlled alignment of the LC molecules may control light (e.g., the polarization of light) propagating through the LC layer to, thereby, enable the display of an image.
Instead of two display panels, an LCD device may include one display panel including cavities formed on a pixel-by-pixel basis. The cavities may be filled with an LC material. The cavities formed on a pixel-by-pixel basis are very small as compared to the space between two display panels typically occupied by a LC layer. As such, technology to fill the cavities with sufficient amounts of LC material, while meeting the requirements (for example, light leakage prevention, electrode insulation, etc.) for securing display quality is required.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the inventive concept, 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.
One or more exemplary embodiments provide a display device configured to prevent (or at least reduce) defective dropping of a controllable material (e.g., liquid crystal material), as well as configured to prevent (or at least reduce) light leakage and short circuiting between a pixel electrode and a common electrode.
Additional aspects will be set forth in part in the detailed description which follows, and, in part, will be apparent from the disclosure, or may be learned by practice of the inventive concept.
According to one or more exemplary embodiments, a display device includes a pixel electrode disposed in a pixel region and a light-shielding member partially overlapping the pixel electrode. A roof layer faces the pixel electrode. The roof layer includes a color filter and a pillar portion extending toward the light-shielding member. A cavity is formed between the pixel electrode and the roof layer. A common electrode is disposed on the roof layer. An inlet exposes a portion of the cavity. A controllable material is disposed in the cavity. A cover layer seals the inlet. The light-shielding member includes a first region corresponding to the pillar portion and a second region adjacent to the first region. A thickness of the first region is different from a thickness of the second region.
According to one or more exemplary embodiments, a display device includes: a pixel electrode disposed in a pixel region; a light-shielding member partially overlapping the pixel electrode; and a roof layer facing the pixel electrode. The roof layer includes a pillar portion extending toward the light-shielding member. A cavity is formed between the pixel electrode and the roof layer. A common electrode is disposed on the roof layer. A controllable material is disposed in the cavity. The light-shielding member includes a protrusion portion protruding toward the pillar portion.
According to one or more exemplary embodiments, a display device may prevent (or at least reduce) defective dropping of the controllable material (e.g., liquid crystal material), as well as prevent (or at least reduce) a short circuit between a pixel electrode and a common electrode. One or more exemplary embodiments may also prevent (or at least reduce) light leakage using a light-shielding member having different thicknesses at various regions.
The foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the claimed subject matter.
The accompanying drawings, which are included to provide a further understanding of the inventive concept, and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the inventive concept, and, together with the description, serve to explain principles of the inventive concept.
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.
Unless otherwise specified, the illustrated exemplary embodiments are to be understood as providing exemplary features of varying detail of various exemplary embodiments. Therefore, unless otherwise specified, the features, components, modules, layers, films, panels, regions, processes, and/or aspects of the various illustrations may be otherwise combined, separated, interchanged, and/or rearranged without departing from the disclosed exemplary embodiments. For example, two consecutively described processes may be performed substantially at the same time or performed in an order opposite to the described order. Further, 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.
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.
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, and/or section from another element, component, region, layer, and/or section. Thus, a first element, component, region, layer, and/or section discussed below could be termed a second element, component, region, layer, and/or section without departing from the teachings of the present disclosure.
Spatially relative terms, such as “beneath,” “below,” “lower,” “above,” “upper,” and 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, operation, and/or manufacture 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.
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,” “comprising,” “includes,” and/or “including,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, components, and/or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
Various exemplary embodiments are described herein with reference to sectional illustrations that are schematic illustrations of idealized exemplary embodiments and/or intermediate structures. As such, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Thus, exemplary embodiments disclosed herein should not be construed as limited to the particular illustrated shapes of regions, but are to include deviations in shapes that result from, for instance, manufacturing. For example, an implanted region illustrated as a rectangle will, typically, have rounded or curved features and/or a gradient of implant concentration at its edges rather than a binary change from implanted to non-implanted region. Likewise, a buried region formed by implantation may result in some implantation in the region between the buried region and the surface through which the implantation takes place. Thus, the regions illustrated in the drawings are schematic in nature and their shapes are not intended to illustrate the actual shape of a region of a device and are not intended to be limiting.
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.
Although various exemplary embodiments are described with respect to liquid crystal display devices, it is contemplated that various exemplary embodiments are also applicable to other display devices, such as, for example, electrophoretic displays, electrowetting displays, plasma displays, and the like.
Referring to
A storage electrode 130 is located in the pixel region and spaced apart from the gate line 120. Although
A gate insulating layer 140 is disposed on the gate line 120 and the storage electrode 130. A semiconductor layer 154 is located on the gate insulating layer 140. The semiconductor layer 154 may include, for instance, amorphous silicon (a-Si), polycrystalline silicon (poly-Si), a metal oxide, etc. The source electrode 173 protrudes from the data line 170 and a drain electrode 175 spaced apart from the source electrode 173 are located on the semiconductor layer 154.
The gate electrode 124, the semiconductor layer 154, the source electrode 173, and the drain electrode 175 form a thin film transistor (TFT). A channel of the TFT is disposed in a partial region of the semiconductor layer 154; that is, a region between the source electrode 173 and the drain electrode 175. When the TFT is in an on-state, a data signal applied to the source electrode 173 is transferred to the drain electrode 175. The data line 170, the source electrode 173, and the drain electrode 175 are covered with an insulating layer 180.
A pixel electrode 190 is disposed on the insulating layer 180 and corresponds to a pixel region. The pixel electrode 190 is electrically connected with the TFT via a contact hole 185 formed in the insulating layer 180. When the TFT is in an on-state, the pixel electrode 190 receives a data signal from the drain electrode 175. The pixel electrode 190 may include a transparent conductive material, such as aluminum zinc oxide (AZO), gallium zinc oxide (GZO), indium tin oxide (ITO), indium zinc oxide (IZO), etc. It is also contemplated that one or more conductive polymers (ICP) may be utilized, such as, for example, polyaniline (PANI), poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS), etc.
The pixel electrode 190 may include a horizontal stem portion 190a, a vertical stem portion 190b crossing the horizontal stem portion 190a and branch portions 190c. According to one or more exemplary embodiments, the pixel region may be divided into four sub-regions by the horizontal stem portion 190a and the vertical stem portion 190b. To this end, each sub-region may include the branch portions 190c. Exemplary embodiments, however, are not limited to the aforementioned configuration of the pixel electrode 190. The pixel electrode 190 may also include an extension portion 190d extending from the pixel region. The extension portion 190d is electrically connected with the drain electrode 175 via the contact hole 185 formed in the insulating layer 180.
A light-shielding member 220 includes a material through which light cannot pass, such as carbon black, chromium, etc. The light-shielding member 220 includes a first light-shielding portion 220a that extends along the first direction D1 and overlaps the gate line 120. The first light-shielding portion 220a has a determined width that overlaps not only the gate line 120, but also a portion of the pixel electrode 190; for example, the extension portion 190d of the pixel electrode 190. The light-shielding member 220 may also include a second light-shielding portion 220b that extends along the second direction D2 to cross the first light-shielding portion 220a. The second light-shielding portion 220b may be integrally formed with the first light-shielding portion 220a. Although
A lower alignment layer 11 is disposed on the pixel electrode 190, and an upper alignment layer 21 is disposed under a common electrode 350. The upper alignment layer 21 faces the lower alignment layer 11. The lower alignment layer 11 and the upper alignment layer 21 may include materials, such as polyimide, polyamic acid, polysiloxane, etc. The lower alignment layer 11 and the upper alignment layer 21 may be vertical alignment layers. The lower alignment layer 11 and the upper alignment layer 21 may be connected with each other via a cavity 305, such as illustrated in
The common electrode 350 is located on the upper alignment layer 21. The common electrode 350 receives a common voltage Vcom and forms an electric field with the pixel electrode 190 to control a direction in which the LC molecules are aligned. A partial region of the common electrode 350 corresponding to the LC inlet OP is open so that the LC molecules may be dropped into the cavity 305 via the LC inlet OP. The common electrode 190 may include a transparent conductive material, such as aluminum zinc oxide (AZO), gallium zinc oxide (GZO), indium tin oxide (ITO), indium zinc oxide (IZO), etc. It is also contemplated that one or more conductive polymers (ICP) may be utilized, such as, for example, polyaniline (PAM), poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS), etc.
A roof layer 360 is located on the common electrode 350. The roof layer 360 includes color filters 360R, 360G, and 360B. For instance, the roof layer 360 may include red, green, and blue color filters 360R, 360G, and 360B, but exemplary embodiments are not limited thereto. For example, the roof layer 360 may include cyan, magenta, and yellow color filters, or any other suitable color.
The cavity 305 is formed between the pixel electrode 190 and the common electrode 350 by the roof layer 360. The roof layer 360 includes a partition wall 363 that partially surrounds the pixel region. The partition wall 363 may be disposed along the edge of the pixel region except a side of the pixel region in which the LC inlet OP is formed.
A cover layer 370 is located on the roof layer 360. The cover layer 370 covers the LC inlet OP. The cover layer 370 seals the LC inlet OP so that the LC molecules disposed inside the cavity 305 do not leak out to the outside. Since the cover layer 370 contacts the LC molecules, the cover layer 370 may include a material that does not react with the LC molecules, such as parylene. The cover layer 370 may include a single layer or multiple layers. When the cover layer 370 includes multiple layers, the layers may include different materials, respectively. For example, the cover layer 370 may include a layer including an organic insulating material and a layer including an inorganic insulating material.
With continued reference to
The first light-shielding portion 220a includes protrusion portions 221 and 222 respectively corresponding to the pillar portions 361 and 362 of the roof layer 360. As illustrated in
The common electrode 350 is located on the inner surface of the roof layer 360; that is, on a first side facing the pixel electrode 190. Since the roof layer 360 includes the pillar portions 361 and 362, a portion of the common electrode 350 is located on the lower surfaces of the pillar portions 361 and 362. In this manner, a first distance H1 (see
The first light-shielding portion 220a may prevent (or at least reduce) an electrical short circuit between the common electrode 350 and the pixel electrode 190, as well as prevent (or at least reduce) defective dropping of the LC molecules via the LC inlet OP by including the first region A1 and the second region A2 respectively having different thicknesses. The first thickness t1 of the first region A1 of the first light-shielding portion 220a that includes the protrusion portions 221 and 222 may be greater than the second thickness t2 of the second region A2 to prevent an electrical short circuit between the common electrode 350 and the pixel electrode 190. The second thickness t2 of the second region A2 of the first light-shielding portion 220a that forms the LC inlet OP may be less than the first thickness t1 of the first region A1 to increase a distance between the first light-shielding portion 220a and the roof layer 360; that is, the height of the LC inlet OP.
When the first thickness t1 of the first light-shielding portion 220a is uniform, the height of the LC inlet OP reduces, and, as such, a defective dropping issue involving a material forming the upper alignment layer 21 and the lower alignment layer 11 and an LC material forming the LC molecules may not be properly dropped. To resolve (or address) the defective dropping of the alignment material and the LC material, the second thickness t2 of the first light-shielding portion 220a may be uniform. However, when the second thickness t2 of the first light-shielding portion 220a is small, the first light-shielding portion 220a may have insufficient second thickness t2 for suppressing light leakage, and the distance between the common electrode 350 and the pixel electrode 190 may be insufficient to prevent a short circuit between the common electrode 350 and the pixel electrode 190.
In contrast, according to one or more exemplary embodiments, the first thickness t1 of the first region A1 and the second thickness t2 of the second region A2 are different from each other. In this manner, defective dropping of the LC material may be resolved, light leakage may be suppressed, and a short circuit between the common electrode 350 and the pixel electrode 190 may be prevented.
Referring to
The data line 170, the source electrode 173 that extends from the data line 170, and the drain electrode 175 spaced apart from the source electrode 173 are formed by forming a metallic layer on the semiconductor layer 154 and patterning the metallic layer. The data line 170, the source electrode 173, and the drain electrode 175 are formed in the same layer during the same process. The gate electrode 124, the semiconductor layer 154, the source electrode 173, and the drain electrode 175 form the TFT. The insulating layer 180 is formed on the TFT. The contact hole 185 is formed in the insulating layer 180 to expose the drain electrode 175.
Referring to
Referring to
The first light-shielding portion 220a includes the protrusion portions 221 and 222. The first thickness t1 of the first region A1 of the first light-shielding portion 220a that includes the protrusion portions 221 and 222 is greater than the second thickness t2 of the second region A2 of the first light-shielding portion 220a that does not include the protrusion portions 221 and 222. According to one or more exemplary embodiments, the protrusion portions 221 and 222 that correspond to the first region A1 of the first light-shielding portion 220a are spaced apart from each other, and the second region A2 of the first light-shielding portion 220a that corresponds to a region between the protrusion portions 221 and 222 forms the LC inlet OP.
Although the thickness of the second light-shielding portion 220b may be the same as the second thickness t2 of the second region A2 as illustrated in
Referring to
Referring to
The roof layer 360 is formed on the common electrode 350 and includes color filters 360R, 360G, and 360B of three colors. According to one or more exemplary embodiments, the roof layer 360 may be formed by forming a blue roof layer 360B, shifting a mask to form a red roof layer 360R, and then shifting the mask to form a green roof layer 360G. Although exemplary embodiments have been described with the roof layer 360 including the red, green, and blue color filters 360R, 360G, and 360B, exemplary embodiments are not limited thereto. For instance, the roof layer 360 may include color filters of cyan, magenta, and yellow colors, and/or any other suitable color.
A material forming the roof layer 360 fills the inside of the first and second through-holes 300a and 300b of the sacrificial layer 300 to form the partition wall 363 and the pillar portions 361 and 362. The pillar portions 361 and 362 are located on one side of the roof layer 360, face the protrusion portions 221 and 222, and stably support the roof layer 360. The roof layer 360 may be patterned, such that the roof layer 360 is not formed on a region of the sacrificial layer 300 in which the common electrode 350 is not formed, as seen in
Referring to
Referring to
As illustrated in
The first thickness t1 (see
Referring to
Although certain exemplary embodiments and implementations have been described herein, other embodiments and modifications will be apparent from this description. Accordingly, the inventive concept is not limited to such embodiments, but rather to the broader scope of the presented claims and various obvious modifications and equivalent arrangements.
Number | Date | Country | Kind |
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10-2015-0103876 | Jul 2015 | KR | national |