DISPLAY PANEL AND FABRICATING METHOD THEREOF
A display panel includes a first substrate, a second substrate, a display medium layer, a sealant and a conductor. The first and second substrates are assembled via the sealant that surrounds the display medium layer disposed between the first and second substrates. The second substrate includes a second conductive layer and a passivation layer disposed on the second conductive layer. The passivation layer reveals a portion of the second conductive layer. The conductor electrically connects a first conductive layer of the first substrate to the revealed portion of the second conductive layer and is disposed between the sealant and an edge of the display panel. A first conductive protrusion and a second conductive protrusion are sequentially disposed on one of the first and second substrates to form the conductor. A material of the second conductive protrusion may be formed from a conductive composite material, that may include a curable material.
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The present invention generally relates to an electronic device, in particular, to a display panel.
2. Description of Related ArtLiquid crystal display panels generally include a display medium layer sandwiched between two substrates that may serve as a liquid crystal cell. Each substrate generally includes a conductive layer. The display medium layer includes a display medium material, and the display medium material generally includes liquid crystal molecules that are driven by an electric field established between the substrates. The driving circuit for the liquid crystal display panel may be bonded to one of the substrates and thus a conductive material connected between the two substrates is required for the conductive layer on the other of the substrates to be electrically connected to the driving circuit. Adding conductive particles to an adhesive is one way of forming the conductive material placed between the substrates. However, the particles tend to aggregate causing non-uniformity in the cell gap between the substrates. The non-uniformity of the cell gap or deviation from parallel alignment of the two substrates affects the quality of the display panel. This adverse effect increases where greater amounts of conductive material, and therefore of conductive particles, are used to bridge the cell gap between the substrates.
SUMMARY OF THE INVENTIONA display panel according to the embodiments of the disclosure employs a conductive protrusion to reduce an amount of a conductive composite material including conductive particles that may on aggregation adversely affect the performance of the display panel.
A manufacturing method of a display panel according to the embodiments of the disclosure may produce a display panel having a desirable cell gap.
The disclosure provides a display panel including a first substrate, a second substrate, a display medium layer, a sealant and a conductor. The first substrate includes a first conductive layer. The second substrate is assembled with the first substrate and includes a second conductive layer and a passivation layer disposed on the second conductive layer. The passivation layer reveals a portion of the second conductive layer. The display medium layer is disposed between the first substrate and the second substrate. The sealant is disposed between the first substrate and the second substrate and surrounds the display medium layer. The conductor is disposed between the sealant and an edge of the display panel and is electrically connected between the first conductive layer and the second conductive layer, wherein the conductor is in contact with the revealed portion of the second conductive layer. The conductor includes a first conductive protrusion and a second conductive protrusion. The first conductive protrusion is in contact with one of the first conductive layer and the second conductive layer. The second conductive protrusion connects between the other of the first conductive layer and the second conductive layer and the first conductive protrusion. A material of the first conductive protrusion and a material of the second conductive protrusion are different.
In some embodiments, a height of the first conductive protrusion orthogonal to one of the first substrate and the second substrate is between 0.1 micrometer and 10 micrometers.
In some embodiments, the material of the first conductive protrusion is different from a material of the one of the first conductive layer and the second conductive layer.
In some embodiments, the material of the first conductive protrusion is the same as a material of the one of the first conductive layer and the second conductive layer.
In some embodiments, the first conductive protrusion is a stacked structure including more than one electrically conductive material.
In some embodiments, the first conductive protrusion has a tapered sidewall.
In some embodiments, the material of the second protrusion includes a matrix material and metal particles dispersed in the matrix material. In some of these embodiments, the matrix material includes a curable material.
In some embodiments, the first substrate further includes a first alignment layer disposed on the first conductive layer of the first substrate and facing the second substrate, and the second substrate further includes a second alignment layer disposed on the passivation layer of the second substrate and facing the first substrate.
In some embodiments, at least one of the first alignment layer and the second alignment layer extends to an edge of the conductor.
In some embodiments, at least one of the first alignment layer and the second alignment layer is enclosed by the sealant.
In some embodiments, the conductor is located within an area of at least one of the first alignment layer and the second alignment layer and the conductor penetrates through the at least one of the first alignment layer and the second alignment layer to be in contact with corresponding one of the first conductive layer and the second conductive layer.
In some embodiments, the conductor further includes a third conductive protrusion. The third conductive protrusion is in contact with the other of the first conductive layer and the second conductive layer and the second conductive protrusion is sandwiched between the first conductive protrusion and the third conductive protrusion.
The disclosure further provides a method of fabricating a display panel including the following steps. A first substrate and a second substrate are provided. The first substrate includes a first conductive layer and the second substrate includes a second conductive layer and a passivation layer disposed on the second conductive layer. A sealant material and a first conductive protrusion are formed on one of the first substrate and the second substrate, wherein the first conductive protrusion is located between an edge of the one of the first substrate and the second substrate and the sealant, and is in contact with a corresponding one of the first conductive layer and the second conductive layer. A conductive composite material is formed on the first conductive protrusion. The conductive composite material includes a matrix material and metal particles. The first substrate and the second substrate are assembled via the sealant material. A display medium layer is formed between the first substrate and the second substrate, wherein the display medium layer is surrounded by the sealant material. The sealant material and the conductive composite material are cured to form a sealant and a second conductive protrusion respectively.
In some embodiments, a material of the first conductive protrusion and a material of the second conductive protrusion are different.
In some embodiments, the matrix material includes a curable material.
In some embodiments, the metal particles include nickel particles.
In some embodiments, a material of the first conductive protrusion is the same as the corresponding one of the first conductive layer and the second conductive layer.
In some embodiments, assembling the first substrate and the second substrate causes the conductive composite material to be compressed.
In some embodiments, the other one of the first substrate and the second substrate further includes an alignment layer covering the other one of the first conductive layer and the second conductive layer and the conductive composite material penetrates the alignment layer to be in contact with the other one of the first conductive layer and the second conductive layer during the assembling of the first substrate and the second substrate.
In view of the above, the first conductive protrusion reduces the amount of material of the second protrusion required to electrically connect between the first conductive layer of the first substrate and the revealed portion of the second conductive layer of the second substrate. In embodiments where a precursor material of the second conductive protrusion is a conductive composite material including conductive particles, using less conductive composite material in the display panel prevents or reduces the non-uniformity of the gap between the first and second substrates caused by the aggregation of the conductive particles. Accordingly, the first conductive protrusion prevents or reduces the decreased performance of the display panel due to a non-uniform gap between the first and second substrates.
The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the descriptions, serve to explain the principles of the invention.
Reference will now be made in detail to the present preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the descriptions to refer to the same or like parts.
In
From outermost to innermost layer, the first substrate 110 may include a first support plate 112, a first conductive layer 114 and a first alignment layer 118. The first conductive layer 114 completely covers a side of the first support plate 112 facing the display medium layer 104; alternatively, the first conductive layer 114 may be patterned as required. A material of the first support plate 112 may be glass, quartz, polymer substrate, or the like. A material of the first conductive layer 114 may be a transparent conductive material, such as metal oxides including indium tin oxide (ITO), aluminum zinc oxide (AZO) or indium zinc oxide (IZO).
From outermost to innermost layer, the second substrate 120 may include a transistor array substrate including a second support plate 122, a second conductive layer 124, a passivation layer 126 and a second alignment layer 128. The second conductive layer 124 is disposed at a side of the second support plate 122 facing the display medium layer 104. The second support plate 122 may be a glass plate, a silicon backplane or the like. The second conductive layer 124 may be a layer of a transistor array such as a thin film transistor (TFT) array or a CMOS (Complementary Metal-Oxide Semiconductor) device array. The passivation layer 126 may include an oxide or nitride of the material used for the second conductive layer 124 below or other material that is corrosion resistant to protect the second conductive layer 124 from corrosion. The first conductive layer 114 of the first substrate 110 and the transistor array of the second substrate 120 may provide an electric field across the display medium layer 104 to, for example, drive liquid crystal molecules in the display medium layer 104. The display panel 100 may be a thin-film transistor liquid-crystal display (TFT-LCD) panel or an LCoS (liquid crystal on silicon) display panel. The passivation layer 126 is formed or patterned to reveal a surface of the second conductive layer 124 below, wherein the revealed surface of the second conductive layer 124 is at least large enough to allow the second conductive protrusion 102 to be in contact with the second conductive layer 124. In this particular embodiment, the passivation layer 126 reveals an outer portion of the second conductive layer 124 that extends to an edge of the display panel 100.
The first alignment layer 118 and the second alignment layer 128 interface with the display medium layer 104. In some embodiments, the display medium layer 104 is a liquid crystal layer, and the first alignment layer 118 and the second alignment layer 128 may orient the liquid crystal molecules and induce a pre-tilt angle of the liquid crystal molecules. Properties of the first alignment layer 118, including a material thereof, may be the same as that of the second alignment layer 128, but the present disclosure is not limited thereto. In this particular embodiment, the first alignment layer 118 and the second alignment layer 128 extend to an inner edge of the sealant 106.
The first conductive protrusion 101 and the second conductive protrusion 102 are stacked in a top and bottom manner and the shape of the two protrusions viewed from above may be substantially the same, such that the outline of the first conductive protrusion 101 and the outline of the second conductive protrusion 102 are aligned. The first conductive protrusion 101 and the second conductive protrusion 102 may construct the conductor C shown in
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The sealant material 106m may include a curable material, such as a light curable material. Similarly, the second conductive protrusion material 102m includes the curable matrix material MR with metal particles MP dispersed therein. In some embodiments, the matrix material MR of the second conductive protrusion material 102m may be the same as the sealant material 106m, but the disclosure is not limited thereto. A light or thermal curing step may be performed to the sealant material 106m and the second conductive protrusion material 102m after joining the first substrate 110 and the second substrate 120 to form a sealant 206 and the second conductive protrusion 102 respectively, such that the display panel 200 may be formed. In alternative embodiments, the display medium material 104m may be introduced into the display medium space via a vacuum injection process after the assembly of the first substrate 110 and the second substrate 120 via the cured sealant 206. Namely, the injection of the display medium material 104m may be performed after the formation of the sealant 206 and the conductor consisting of the first conductive protrusion 101 and the second conductive protrusion 102.
The display panel 200 is similar to the display panel 100 shown in
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The hydrophobic surfaces 118s and 128s may have a water contact angle greater than 60 degrees. In the present embodiment, the entire surfaces of the first alignment layer 118 and the second alignment layer 128 facing the display medium layer 104 may be modified. However, the present disclosure is not limited thereto. The hydrophobic surface may be formed directly as or patterned to a desired pattern. For instance, the hydrophobic molecules on a portion of the hydrophobic surface 118s and/or a portion of the hydrophobic surface 128s may be removed by UV exposure or plasma etching.
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In another similar embodiment to that of the display panel 1000 of
The conductor spanning the gap between the first conductive layer 114 and the second conductive layer 124 of
The third conductive protrusion 103 may be of a different material to the second conductive layer 124, and so may be formed on the second conductive layer 124 in a similar manner to the first conductive protrusion 101 being formed on the second conductive layer 124 of the display panel 900 of
The second conductive protrusion 102 may be similar to and formed in a similar manner to the second conductive protrusion 102 in previous embodiments, such as that of the display panel 200 of
The display panel 1100 is otherwise formed in a similar manner to that of the display panel 200 of
In view of the above, the first conductive protrusion reduces the amount of material of the second protrusion required to electrically connect between the first conductive layer of the first substrate and the revealed portion of the second conductive layer of the second substrate. In embodiments where a precursor material of the second conductive protrusion is a conductive composite material including conductive particles, using less conductive composite material in the display panel prevents or reduces the non-uniformity of the gap between the first and second substrates caused by the aggregation of the conductive particles. Accordingly, the first conductive protrusion prevents or reduces the decreased performance of the display panel due to a non-uniform gap between the first and second substrates.
It will be apparent to those skilled in the art that various modifications and variations can be made to the embodiments and concepts disclosed herein without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the present disclosure cover modifications and variations of this invention provided they fall within the scope of the following claims and their equivalents.
Claims
1. A display panel comprising:
- a first substrate comprising a first conductive layer;
- a second substrate assembled with the first substrate and comprising a second conductive layer and a passivation layer disposed on the second conductive layer, wherein the passivation layer reveals a portion of the second conductive layer;
- a display medium layer disposed between the first substrate and the second substrate;
- a sealant disposed between the first substrate and the second substrate and surrounding the display medium layer;
- a conductor disposed between the sealant and an edge of the display panel and electrically connected between the first conductive layer and the second conductive layer, wherein the conductor is in contact with the revealed portion of the second conductive layer and the conductor comprises: a first conductive protrusion in contact with one of the first conductive layer and the second conductive layer; and a second conductive protrusion connecting between the other of the first conductive layer and the second conductive layer and the first conductive protrusion, wherein a material of the first conductive protrusion and a material of the second conductive protrusion are different, wherein the first conductive protrusion is a stacked structure comprising more than one electrically conductive material.
2. The display panel according to claim 1, wherein a height of the first conductive protrusion orthogonal to the one of the first substrate and the second substrate is between 0.1 micrometer and 10 micrometers.
3. The display panel according to claim 1, wherein the material of the first conductive protrusion is different from a material of the one of the first conductive layer and the second conductive layer.
4. The display panel according to claim 1, wherein the material of the first conductive protrusion is the same as a material of the one of the first conductive layer and the second conductive layer.
5. (canceled)
6. The display panel according to claim 1, wherein the first conductive protrusion has a tapered sidewall.
7. The display panel according to claim 1, wherein the material of the second protrusion comprises a matrix material and metal particles dispersed in the matrix material.
8. The display panel according to claim 7, wherein the matrix material comprises a curable material.
9. The display panel according to claim 1, wherein
- the first substrate further comprises a first alignment layer disposed on the first conductive layer of the first substrate and facing the second substrate; and
- the second substrate further comprises a second alignment layer disposed on the passivation layer of the second substrate and facing the first substrate.
10. The display panel according to claim 9, wherein at least one of the first alignment layer and the second alignment layer extends to an edge of the conductor.
11. The display panel according to claim 9, wherein at least one of the first alignment layer and the second alignment layer is enclosed by the sealant.
12. The display panel according to claim 9, wherein the conductor is located within an area of at least one of the first alignment layer and the second alignment layer and the conductor penetrates through the at least one of the first alignment layer and the second alignment layer to be in contact with corresponding one of the first conductive layer and the second conductive layer.
13. The display panel according to claim 1, wherein the conductor further comprises a third conductive protrusion, the third conductive protrusion is in contact with the other of the first conductive layer and the second conductive layer and the second conductive protrusion is sandwiched between the first conductive protrusion and the third conductive protrusion.
14. A method of fabricating a display panel comprising:
- providing a first substrate comprising a first conductive layer and a second substrate comprising a second conductive layer and a passivation layer disposed on the second conductive layer;
- forming a sealant material on one of the first substrate and the second substrate;
- forming a first conductive protrusion on the one of the first substrate and the second substrate, wherein the first conductive protrusion is located between an edge of the one of the first substrate and the second substrate and the sealant, and in contact with a corresponding one of the first conductive layer and the second conductive layer; and
- forming a conductive composite material on the first conductive protrusion, wherein the conductive composite material comprises a matrix material and metal particles;
- assembling the first substrate and the second substrate via the sealant material;
- forming a display medium layer between the first substrate and the second substrate, wherein the display medium layer is surrounded by the sealant material; and
- curing the sealant material and the conductive composite material to form a sealant and a second conductive protrusion respectively.
15. The method of claim 14, wherein a material of the first conductive protrusion and a material of the second conductive protrusion are different.
16. The method of claim 14, wherein the matrix material comprises a curable material.
17. The method of claim 14, wherein the metal particles comprise nickel particles.
18. The method of claim 14, wherein a material of the first conductive protrusion is the same as the corresponding one of the first conductive layer and the second conductive layer.
19. The method of claim 14, wherein assembling the first substrate and the second substrate causes the conductive composite material to be compressed.
20. The method of claim 19, wherein the other one of the first substrate and the second substrate further comprises an alignment layer covering the other one of the first conductive layer and the second conductive layer and the conductive composite material penetrates the alignment layer to be in contact with the other one of the first conductive layer and the second conductive layer during the assembling of the first substrate and the second substrate.
Type: Application
Filed: Apr 3, 2019
Publication Date: Oct 8, 2020
Applicant: Himax Display, Inc. (Tainan City)
Inventor: Po-Hung Pan (Tainan City)
Application Number: 16/373,655