TWI439982B - Pixel array substrate and reflective display panel - Google Patents

Description

Pixel array substrate and reflective display panel

The present invention relates to a pixel array substrate and a reflective display panel, and more particularly to a pixel array substrate having a barrier structure and a reflective display panel.

In recent years, as various display technologies continue to flourish, after continuous development research, products such as electrophoretic displays, liquid crystal displays, plasma displays, and organic light-emitting diode displays have been gradually commercialized and applied to various sizes. In the display device. With the increasing popularity of portable electronic products, flexible displays (such as e-paper, e-books, etc.) have gradually gained market attention.

In general, e-paper and e-book use electrophoretic display technology to achieve display. Taking an electronic book showing black and white as an example, the electrophoretic display used mainly includes a thin film transistor array substrate, a retaining wall structure, and an electrophoretic display medium accommodated in the retaining wall structure. The electrophoretic display medium is mainly composed of a black electrophoresis liquid and white charged particles doped in a black electrophoresis liquid. By applying a voltage, the white charged particles can be moved to reflect external light, thereby causing the electrophoretic display to display various different images.

However, the black electrophoresis liquid in the electrophoretic display cannot completely absorb the external light, so some external light passes through the electrophoretic display medium and enters the thin film transistor array substrate. In this way, the light will be covered by the film. The thin film transistor or other metal traces in the transistor array substrate are reflected, causing the contrast ratio of the electrophoretic display to decrease. Therefore, it has been proposed to make a black light absorbing layer between the thin film transistor array substrate and the retaining wall structure, thereby reducing the probability of the external light source being reflected. However, this black light absorbing layer requires an additional reticle, which is costly and time consuming. In addition, the black light absorbing layer and the retaining wall structure tend to have poor alignment problems in the process, and when the adhesion between the black light absorbing layer and the retaining wall structure is insufficient, the retaining wall structure is easy to follow the process or the reliability test. A situation in which peeling occurs.

In view of the above, the present invention provides a pixel array substrate and a reflective display panel, which can improve the problem that the retaining wall structure of the conventional pixel array substrate and the reflective display panel is easily peeled off from the bottom layer. In addition, the pixel array substrate and the reflective display panel of the present invention can also solve the problem of poor alignment between the retaining wall structure and the bottom layer.

The invention provides a pixel array substrate comprising a substrate, an element array, a light absorbing layer and a retaining wall structure. The substrate has a plurality of pixel regions and a barrier region arranged in an array. The wall area is located between any two adjacent pixel areas and surrounds the outermost periphery of these pixel areas. The array of elements has a plurality of elements located in the respective pixel regions. The light absorbing layer covers the array of elements, the pixel area of the substrate, and the wall area. The retaining wall structure is located on the light absorbing layer, and surrounds the receiving opening in each pixel area, wherein the light absorbing layer and the retaining wall structure are integrally formed.

The present invention provides a reflective display panel including the above-described pixel array substrate, a counter substrate, and a display medium. The opposite substrate is opposite to the pixel array substrate and connected to the retaining wall structure to close the receiving opening. The display medium is located in the receiving opening.

In an embodiment of the invention, the light absorbing layer is the same material as the retaining wall structure.

In an embodiment of the invention, the light absorbing layer and the retaining wall structure comprise a black light absorbing layer.

In an embodiment of the invention, the material of the light absorbing layer and the retaining wall structure comprises a black resin.

In one embodiment of the invention, the light absorbing layer described above comprehensively covers the array of elements, the pixel regions of the substrate, and the wall regions.

In an embodiment of the invention, the substrate further has a peripheral region surrounding the periphery of the pixel region, and the light absorbing layer and the barrier structure expose the peripheral region.

In an embodiment of the invention, the component comprises an active component and a pixel electrode, and the pixel electrode is electrically connected to the active component.

In an embodiment of the invention, the opposite substrate may further include a common electrode.

Based on the above, in the pixel array substrate and the reflective display panel of the present invention, since the light absorbing layer and the retaining wall structure are integrally formed and have high mechanical strength, peeling of the retaining wall structure from the light absorbing layer can be avoided. In addition, since the light absorbing layer and the retaining wall structure are formed together, there is no problem of poor alignment between the retaining wall structure and the light absorbing layer.

The above described features and advantages of the present invention will be more apparent from the following description.

1 is a schematic cross-sectional view of a pixel array substrate according to an embodiment of the present invention, and FIG. 2 is a schematic top view of a pixel array substrate according to an embodiment of the present invention, wherein FIG. 1 is a cross-sectional line A-A' corresponding to FIG. Sectional view. Referring to FIG. 1 and FIG. 2 simultaneously, the pixel array substrate 100 of the present embodiment includes a substrate 102, an element array 104, a light absorbing layer 106, and a retaining wall structure 108.

The substrate 102 of the present embodiment has a plurality of arrays of pixel regions P and a barrier wall region W, and the barrier region W is located between any two adjacent pixel regions P and surrounds the outermost periphery of the pixel region P. For example, the plurality of pixel regions P may be rectangular regions in which a plurality of arrays are arranged, and the barrier region W may be a mesh region surrounding the pixel regions P, but the present invention is not limited thereto. In addition, the substrate 102 of the present embodiment has a peripheral region K, and the peripheral region K surrounds the periphery of the retaining wall region W, and the light absorbing layer 106 and the retaining wall structure 108 are not formed on the peripheral region K, in other words, the light absorbing layer The 106 and retaining wall structure 108 exposes the peripheral zone K of the substrate 102. In this embodiment, the substrate 102 is mainly used to carry the components of the pixel array substrate 100, and the material thereof may be glass, quartz, organic polymer, or opaque material (for example, conductive materials, wafers, ceramics, etc.) ).

The element array 104 of the present embodiment has a plurality of elements 104a located in the pixel area P, respectively. In the present embodiment, the element 104a includes an active element T and a pixel electrode PX, and the pixel electrode PX is electrically connected to the active element T. In this In the embodiment, the active device T is, for example, a thin film transistor (TFT), and the pixel electrode PX is, for example, a conductive electrode, and the material thereof includes a metal, a metal oxide (eg, indium tin oxide, indium zinc oxide, aluminum). Tin oxide, aluminum zinc oxide, indium antimony zinc oxide, or other suitable oxide, or a stacked layer of at least two of the foregoing.

The light absorbing layer 106 of the present embodiment covers the element array 104, the pixel region P of the substrate, and the barrier region W. Further, the light absorbing layer 106 can comprehensively cover the pixel area P and the wall area W, thereby sufficiently absorbing light incident from the outside, thereby reducing the probability of light being reflected by the active element T or other metal traces. . In this way, the reflective display panel using the pixel array substrate 100 of the present embodiment can greatly reduce the probability of occurrence of dark state light leakage, thereby improving the contrast ratio of the reflective display panel. In the present embodiment, the light absorbing layer 106 may be a black light absorbing layer, the material of which is, for example, a black resin.

The retaining wall structure 108 of the present embodiment is located on the light absorbing layer 106, and the retaining wall structure 108 encloses the receiving opening H in each of the pixel regions P. In other words, the retaining wall structure 108 of the present embodiment is located on and substantially coincides with the retaining wall region W distributed in a mesh shape, so that the receiving openings H of the retaining wall structure 108 just expose the light absorbing layer above each pixel region P. 106, so that the retaining wall structure 108 surrounds the receiving opening H together with the light absorbing layer 106 on each of the pixel areas P for filling the display medium in a subsequent process. In other words, when the pixel array substrate 100 constitutes a reflective display panel, the accommodating spaces filled with the display medium are the positions of the display unit, and each of the accommodating openings H is, for example, a rectangular frame.

It is worth mentioning that the light absorbing layer 106 and the retaining wall structure 108 are one. Body shaping. In other words, the light absorbing layer 106 is fabricated together with the retaining wall structure 108. For example, a black light absorbing layer 110 (shown in FIG. 3A) may be coated on the substrate 102, and then a half tone or gray tone mask M may be used, as shown in FIG. 3B. The mask M has a pattern of a penetrating region R1, a semi-transmissive region R2, and a light-shielding region R3, whereby the mask M performs a yellow light process on the black light absorbing layer 110 to simultaneously form on the element array 104. The light absorbing layer 106 having different thicknesses, the barrier structure 108, and the black light absorbing layer 110 on the peripheral region K are simultaneously removed to expose the peripheral region K of the substrate 102.

For example, the black light absorbing layer 110 of the embodiment is, for example, a negative black photoresist, and the light passing through the penetration region R1 of the reticle M is irradiated onto the black photoresist so that the corresponding penetration region R1 is black. The photoresist is cured by hardening, and after development, a region having a thick thickness D1 is formed, correspondingly constituting a laminate of the light absorbing layer 106 and the retaining wall structure 108; on the other hand, light passing through the semi-transmissive region R2 of the mask M is irradiated On the black photoresist, a portion of the black photoresist corresponding to the transmissive region R1 is polymerized and hardened, and after development, a region having a thin thickness D2 is formed on the light absorbing layer 106, correspondingly constituting the light absorbing layer 106; The black photoresist under the light-shielding region R3 of the cover M is completely removed after development due to the absence of light to expose the peripheral region K of the substrate. Since the black light absorbing layer 110 has different thicknesses after patterning, a plurality of receiving openings H (shown in FIG. 3B) are formed in a region where the thickness D2 is thin. The black light absorbing layer 110 having a plurality of receiving openings H is the light absorbing layer 106 and the retaining wall structure 108 described above.

Since the light absorbing layer 106 and the retaining wall structure 108 of the embodiment are one The formed body has a high mechanical strength, so the pixel array substrate 100 of the present embodiment is less prone to peeling of the light absorbing layer 106 and the retaining wall structure 108 in a subsequent process or reliability test. . In addition, since the light absorbing layer 106 and the retaining wall structure 108 are formed together in the same reticle process, the pixel array substrate 100 of the present embodiment also has no light absorbing layer 106 and a retaining wall in the conventional pixel array substrate. The problem of structure 108 alignment. In the present embodiment, the light absorbing layer 106 and the retaining wall structure 108 are made of the same material using the same material (such as black resin). Therefore, the pixel array substrate 100 of the present embodiment can save the manufacturing cost and time of a photomask compared with the conventional pixel array substrate, thereby reducing the manufacturing cost of the pixel array substrate 100 of the embodiment.

4 is a cross-sectional view of a reflective display panel in accordance with an embodiment of the present invention. The reflective display panel 1000 of the present embodiment includes the above-described pixel array substrate 100, the opposite substrate 200, and the display medium 300. The opposite substrate 200 is opposed to the pixel array substrate 100, and is connected to the retaining wall structure 108 to close the receiving openings H, and the display medium 300 is sealed in the receiving openings H. In the present embodiment, the opposite substrate 200 includes the opposite substrate 202 and the common electrode 204, and the common electrode 204 is located between the opposite substrate 202 and the pixel array substrate 100. When there is a potential difference between the common electrode 204 and the pixel electrode PX, the display medium 300 located at the receiving opening H is driven, so that the reflective display panel 1000 of the present embodiment can display various screens. Of course, in other embodiments, the opposite substrate 200 may further include a color filter to enable the reflective display panel to display a color picture. In this embodiment, the display medium 300 can be an electrophoresis liquid and a charged reflection A mixture of particles or cholesteric liquid crystal, but the invention is not limited thereto.

In summary, in the pixel array substrate and the reflective display panel of the present invention, since the light absorbing layer and the retaining wall structure are integrally formed, the pixel array substrate and the reflective display panel of the present invention are in a process or In the reliability test, the problem of peeling off of the light absorbing layer and the retaining wall structure is less likely to occur. In addition, since the light absorbing layer and the retaining wall structure are formed in the same reticle process, the pixel array substrate and the reflective display panel of the present invention also have no light absorbing layer and retaining wall in the conventional pixel array substrate. The problem of structural alignment.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the invention, and any one of ordinary skill in the art can make some modifications and refinements without departing from the spirit and scope of the invention. The scope of the invention is defined by the scope of the appended claims.

100‧‧‧Array substrate

102‧‧‧Base

104‧‧‧Component array

104a‧‧‧ components

106‧‧‧Light absorbing layer

108‧‧‧Retaining wall structure

110‧‧‧Black light absorbing layer

200‧‧‧ opposite substrate

202‧‧‧ opposite base

204‧‧‧Common electrode

300‧‧‧Display media

1000‧‧‧reflective display panel

P‧‧‧Photo District

W‧‧‧Retaining wall area

K‧‧‧ surrounding area

T‧‧‧ active components

PX‧‧‧ pixel electrode

H‧‧‧ accommodation opening

R1, R2, R3‧‧‧ areas

D1, D2‧‧‧ thickness

M‧‧‧Photo Mask

1 is a schematic cross-sectional view of an array substrate according to an embodiment of the present invention.

2 is a schematic top view of an array substrate according to an embodiment of the invention.

3A to 3B illustrate a manufacturing process of a light absorbing layer and a retaining wall structure according to an embodiment of the present invention.

4 is a cross-sectional view of a reflective display panel in accordance with an embodiment of the present invention.

100‧‧‧Array substrate

102‧‧‧Base

104‧‧‧Component array

104a‧‧‧ components

106‧‧‧Light absorbing layer

108‧‧‧Retaining wall structure

P‧‧‧Photo District

W‧‧‧Retaining wall area

K‧‧‧ surrounding area

T‧‧‧ active components

PX‧‧‧ pixel electrodes

H‧‧‧ accommodation opening

Claims (8)

A reflective display panel comprising: a pixel array substrate, the pixel array substrate comprising: a substrate having a plurality of arrays of pixel regions and a barrier region, the barrier region being located in any two adjacent pixels Between the regions and surrounding the outermost periphery of the pixel regions; an array of elements having a plurality of components respectively located in the pixel regions; a light absorbing layer covering the array of elements, the pixel regions of the substrate, and The retaining wall region; and a retaining wall structure on the light absorbing layer, the retaining wall structure enclosing a receiving opening in each of the pixel regions, and the light absorbing layer and the retaining wall structure are integrally formed; The opposite substrate is opposite to the pixel array substrate and connected to the retaining wall structure to close the receiving openings; and a display medium is located at the receiving openings. The reflective display panel of claim 1, wherein the light absorbing layer is the same material as the retaining wall structure. The reflective display panel of claim 1, wherein the light absorbing layer and the retaining wall structure comprise a black light absorbing layer. The reflective display panel of claim 3, wherein the light absorbing layer and the material of the retaining wall structure comprise a black resin. The reflective display panel of claim 1, wherein the light absorbing layer comprehensively covers the element array, the pixel regions of the substrate, and the retaining wall region. The reflective display panel of claim 1, wherein the substrate further has a peripheral region surrounding the periphery of the pixel regions, the light absorbing layer and the retaining wall structure exposing the peripheral region of the substrate . The reflective display panel of claim 1, wherein each of the components comprises an active component and a pixel electrode, and the pixel electrode is electrically connected to the active component. The reflective display panel of claim 1, wherein the opposite substrate further comprises a common electrode.