Stretchable pixel array substrate

Abstract

A stretchable pixel array substrate includes a substrate, a plurality of island elements, an auxiliary pattern, and conductive lines. The plurality of island elements are respectively disposed on a plurality of pixel regions of the substrate. Each island element includes a pixel driving circuit and has sidewalls. The auxiliary pattern is disposed on a circuit region of the substrate and extends to at least a portion of one of the plurality of pixel regions. The auxiliary pattern covers at least a portion of the sidewalls of the island elements and at least a portion of the upper surface of the island elements facing away from the substrate. Conductors are disposed on the auxiliary pattern and electrically connect the plurality of pixel driving circuits of the plurality of island elements.

Description

[Technical Field]

[0001] The present invention relates to a pixel array substrate, and more particularly to a stretchable pixel array substrate. [Previous Technology]

[0002] With the rapid development of electronic technology, electronic products are constantly being innovated. In order for electronic products to be applicable to various fields, the characteristics of stretchability, thinness, and unrestricted shape are gradually gaining importance. That is to say, electronic products are increasingly required to have different shapes according to different application methods and application environments, therefore electronic products need to be stretchable.

[0003] However, when electronic products are stretched, they may experience structural fractures due to stress, and even further cause internal circuit breaks. Therefore, how to ensure that stretchable electronic products have good manufacturing yield and product reliability is an urgent issue that needs to be addressed. [Summary of the Invention]

[0004] The present invention provides a stretchable pixel array substrate with high reliability.

[0005] The stretchable pixel array substrate of the present invention includes a substrate, a plurality of island elements, an auxiliary pattern, conductive lines, and an insulating layer. The substrate has a plurality of pixel regions and a circuit region, wherein the circuit region is located between and connected to the plurality of pixel regions. The plurality of island elements are respectively disposed on the plurality of pixel regions of the substrate, wherein each island element includes a pixel driving circuit and has a sidewall. The auxiliary pattern is disposed on the circuit region of the substrate and extends at least to at least a portion of one of the plurality of pixel regions. The auxiliary pattern covers at least a portion of the sidewall of the island element and at least a portion of the upper surface of the island element facing away from the substrate. The conductive lines are disposed on the auxiliary pattern and electrically connected to the plurality of pixel driving circuits of the plurality of island elements. The insulating layer covers the conductive lines and the island elements. The auxiliary pattern has a contact window, the contact window of the auxiliary pattern overlapping at least a portion of the upper surface of the island element facing away from the substrate, and the conductive lines are electrically connected to one of the plurality of pixel driving circuits of the plurality of island elements through the contact window of the auxiliary pattern.

[0006] In one embodiment of the present invention, the above-mentioned auxiliary pattern is disposed between at least a portion of the upper surface of the conductor and the island element, the auxiliary pattern is disposed between at least a portion of the sidewall of the conductor and the island element, and the auxiliary pattern is disposed between the conductor and the circuit area of ​​the substrate.

[0007] In one embodiment of the present invention, the vertical projection area of ​​a portion of the above-mentioned conductor on the pixel area of ​​the substrate is less than or equal to the vertical projection area of ​​a portion of the auxiliary pattern on the pixel area of ​​the substrate.

[0008] In one embodiment of the present invention, the Young's modulus of the above-mentioned auxiliary pattern is less than 10 GPa.

[0009] In one embodiment of the present invention, the auxiliary pattern provided on a portion of the upper surface of the island element has a thickness, and the thickness is less than 10 μm.

[0010] In one embodiment of the present invention, the upper surface of the island element includes a peripheral area and a middle area. The peripheral area of ​​the upper surface of the island element is connected between the sidewall of the island element and the middle area of ​​the upper surface of the island element. The auxiliary pattern covers the sidewall of the island element and the peripheral area of ​​the upper surface of the island element, and the auxiliary pattern has an opening that overlaps the middle area of ​​the upper surface of the island element.

[0011] In one embodiment of the present invention, the upper surface of the island element and the sidewall of the island element have a boundary, the boundary includes a plurality of side edges and a plurality of corners disposed between the plurality of side edges; the auxiliary pattern includes a plurality of auxiliary parts that are separated from each other, the plurality of auxiliary parts respectively cross the plurality of side edges of the boundary, and the plurality of corners of the boundary are located between the plurality of auxiliary parts of the auxiliary pattern.

[0012] In one embodiment of the present invention, the upper surface of the island element includes a peripheral area and a middle area. The peripheral area of ​​the upper surface of the island element is connected between the sidewall of the island element and the middle area of ​​the upper surface of the island element. The peripheral area of ​​the upper surface of the island element has multiple side sub-areas and multiple corner sub-areas disposed between the multiple side sub-areas. The auxiliary pattern covers multiple first portions of the sidewall of the island element connected to the multiple side sub-areas, the multiple side sub-areas of the upper surface of the island element, and the middle area of ​​the upper surface of the island element. The auxiliary pattern has multiple notches, which are respectively superimposed on the multiple corner sub-areas of the upper surface of the island element and the multiple second portions of the sidewall of the island element connected to the multiple corner sub-areas. [Simplified Explanation of the Diagram]

[0043] Figure 1 is a three-dimensional schematic diagram of a stretchable pixel array substrate 10 according to an embodiment of the present invention.

[0044] Figure 2 is a schematic diagram of the island element IS, auxiliary pattern 170 and light-emitting diode element 230 of a stretchable pixel array substrate 10 according to an embodiment of the present invention.

[0045] Figure 3 is a cross-sectional schematic diagram of a stretchable pixel array substrate 10 according to an embodiment of the present invention.

[0046] Figure 4 is a top view of the auxiliary pattern 170 and the wire 186 of the stretchable pixel array substrate 10 according to an embodiment of the present invention.

[0047] Figure 5 shows the relationship between the thickness T170 of the auxiliary pattern 170 disposed on a portion of the upper surface ISb of the island element IS and the strain of the island element IS at the end of the conductor 186 in an embodiment of the present invention.

[0048] Figure 6 shows the relationship between the overall strain of the stretchable pixel array substrate 10 and the strain of the island element IS in an embodiment of the present invention under various extension lengths L170.

[0049] Figure 7 is a schematic diagram of the island element IS, auxiliary pattern 170A and light-emitting diode element 230 of a stretchable pixel array substrate 10A according to another embodiment of the present invention.

[0050] Figure 8 is a schematic diagram of the island element IS, auxiliary pattern 170B and light-emitting diode element 230 of the stretchable pixel array substrate 10B according to another embodiment of the present invention.

[0051] Figure 9 is a cross-sectional schematic diagram of a stretchable pixel array substrate 10B according to another embodiment of the present invention.

[0052] Figure 10 is a schematic diagram of the island element IS, auxiliary pattern 170C and light-emitting diode element 230 of the stretchable pixel array substrate 10C according to another embodiment of the present invention.

[0053] Figure 11 is a cross-sectional schematic diagram of a stretchable pixel array substrate 10C according to another embodiment of the present invention.

Implementation Method

[0013] Reference will now be made in detail to exemplary embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same element symbols are used in the drawings and description to denote the same or similar parts.

[0014] It should be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" or "connected" to another element, it may be directly on or connected to the other element, or an intermediate element may also be present. Conversely, when an element is referred to as being "directly on" or "directly connected" to another element, no intermediate element is present. As used herein, "connection" may refer to a physical and / or electrical connection. Furthermore, "electrical connection" or "coupling" may mean the presence of other elements between the two elements.

[0015] As used herein, “about,” “approximately,” or “substantially” includes the value and the average value within an acceptable range of deviations from a particular value as determined by one of ordinary skill in the art, taking into account the measurement in question and a particular number of errors associated with the measurement (i.e., limitations of the measurement system). For example, “about” may mean within one or more standard deviations of the value, or within ±30%, ±20%, ±10%, ±5%. Furthermore, as used herein, “about,” “approximately,” or “substantially” may be used to select a more acceptable range of deviations or standard deviations depending on the optical, etched, or other properties, and may not apply to all properties with a single standard deviation.

[0016] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It will be further understood that terms such as those defined in commonly used dictionaries should be interpreted as having the same meaning as they have in the context of the relevant technology and the present invention, and will not be interpreted as having an idealized or overly formal meaning unless expressly defined herein.

[0017] Figure 1 is a perspective view of a stretchable pixel array substrate 10 according to an embodiment of the present invention. Figure 2 is a schematic diagram of the island element IS, auxiliary pattern 170, and light-emitting diode element 230 of the stretchable pixel array substrate 10 according to an embodiment of the present invention. Figure 3 is a cross-sectional view of the stretchable pixel array substrate 10 according to an embodiment of the present invention. Figure 3 corresponds to the section line I-I' of Figure 1. Figure 1 shows the substrate 110, island element IS, auxiliary pattern 170, and wire 186 of the stretchable pixel array substrate 10 of Figure 3, while omitting other components of the stretchable pixel array substrate 10.

[0018] Referring to Figures 1 and 3, the stretchable pixel array substrate 10 includes a substrate 110. The substrate 110 has a plurality of pixel regions 112 and a circuit region 114, wherein the circuit region 114 is located between and connected to the plurality of pixel regions 112. The substrate 110 is stretchable. For example, in this embodiment, the material of the substrate 110 may be an organic polymer, such as: polyimide (PI), polyethylene naphthalate (PEN), polyethylene terephthalate (PET), polycarbonates (PC), polyether sulfone (PES), or polyarylate, other suitable materials, or combinations of at least two of the foregoing materials, but the present invention is not limited thereto.

[0019] Referring to Figures 1, 2, and 3, the stretchable pixel array substrate 10 further includes a plurality of island elements IS, which are respectively disposed on a plurality of pixel regions 112 of the substrate 110. Each island element IS includes a pixel driving circuit PC and has a sidewall ISa. The sidewall ISa of the island element IS and the pixel region 112 are aligned with the boundary of the line region 114.

[0020] Refer to Figures 1 and 3. In this embodiment, the pixel driving circuit PC of each island element IS may include a thin film transistor T. The thin film transistor T has a control terminal 150, a semiconductor pattern 130, a gate insulating layer 140 disposed between the control terminal 150 and the semiconductor pattern 130, and a first terminal 182 and a second terminal (not shown) electrically connected to two different regions of the semiconductor pattern 130, respectively. The sidewall ISa of the island element IS may include the sidewall 140a of the gate insulating layer 140.

[0021] In this embodiment, each island element IS may selectively include a buffer layer 120, wherein the buffer layer 120 is disposed on the substrate 110, the thin film transistor T is disposed on the buffer layer 120, and the sidewall ISa of the island element IS may selectively include the sidewall 120a of the buffer layer 120, but the present invention is not limited thereto. In this embodiment, each island element IS may selectively include an interlayer dielectric layer 160, which may be composed of a single film layer or multiple film layers stacked in phase, the interlayer dielectric layer 160 being disposed between the first end 182 of the thin film transistor T and the control end 150, and the sidewall ISa of the island element IS may selectively include the sidewall 160a of the interlayer dielectric layer 160, but the present invention is not limited thereto.

[0022] Referring to Figures 1, 2, and 3, the stretchable pixel array substrate 10 further includes an auxiliary pattern 170 disposed on the line area 114 of the substrate 110 and extending at least to at least a portion of the pixel area 112. The auxiliary pattern 170 covers at least a portion of the sidewall ISa of the island element IS and at least a portion of the upper surface ISb of the island element IS facing away from the substrate 110. Referring to Figures 1 and 3, for example, in this embodiment, the upper surface ISb of the island element IS includes a peripheral area ISb-2 and a middle area ISb-1. The peripheral area ISb-2 of the upper surface ISb of the island element IS is connected between the side wall ISa of the island element IS and the middle area ISb-1 of the upper surface ISb of the island element IS. The auxiliary pattern 170 covers the side wall ISa of the island element IS and the peripheral area ISb-2 of the upper surface ISb of the island element IS. The auxiliary pattern 170 may have an opening 172, and the opening 172 overlaps with the middle area ISb-1 of the upper surface ISb of the island element IS, but the present invention is not limited thereto.

[0023] The auxiliary pattern 170 can be made of various photosensitive materials with a buffering effect. For example, in this embodiment, the Young's modulus of the auxiliary pattern 170 can be less than 10 GPa; the material of the auxiliary pattern 170 can be polyimide (PSPI), phenol-formaldehyde resin, epoxy resin, polyisoprene rubber, or other suitable materials; however, the present invention is not limited thereto.

[0024] Referring to Figures 1 and 3, the stretchable pixel array substrate 10 further includes wires 186 disposed on the auxiliary pattern 170 and electrically connected to multiple pixel driving circuits PC of multiple island elements IS. For example, in this embodiment, the wires 186 may be gate driving lines, common lines, power lines, or data lines electrically connected to multiple pixel driving circuits PC of multiple island elements IS, but the present invention is not limited thereto.

[0025] The auxiliary pattern 170 has a contact window 174, which overlaps at least a portion of the upper surface ISb of the island element IS facing away from the substrate 110. The conductor 186 can extend from the line area 114 of the substrate 110 toward the pixel area 112 of the substrate 110 to cross over the auxiliary pattern 170 covering the island element IS, and is electrically connected to the pixel driving circuit PC of the island element IS through the contact window 174 of the auxiliary pattern 170. In this embodiment, the conductor 186 can also selectively be electrically connected to the pixel driving circuit PC of the island element IS through the contact window 162 of the interlayer dielectric layer 160, but the present invention is not limited thereto.

[0026] In this embodiment, the wire 186 is made of a metallic material for conductivity considerations. However, the invention is not limited thereto, and in other embodiments, the wire 186 may also be made of other conductive materials. For example: alloys, nitrides of metallic materials, oxides of metallic materials, oxynitrides of metallic materials, or stacked layers of metallic materials and other conductive materials.

[0027] Referring to Figures 1 and 3, the stretchable pixel array substrate 10 further includes an insulating layer 190 covering the conductive lines 186 and the island elements IS. The insulating layer 190 can also be called a protective layer. In this embodiment, the material of the insulating layer 190 can be an inorganic material (e.g., silicon oxide, silicon nitride, silicon oxynitride, or a stacked layer of at least two of the above materials), an organic material, or a combination thereof.

[0028] Referring to Figures 1 and 3, in this embodiment, the stretchable pixel array substrate 10 may further include a conductive pattern 200 disposed on the insulating layer 190 and electrically connected to the pixel driving circuit PC of the island element IS. In this embodiment, the stretchable pixel array substrate 10 may further include a planarization layer 210 disposed on the conductive pattern 200. In this embodiment, the stretchable pixel array substrate 10 may further include a transparent conductive pattern 220 disposed on the planarization layer 210 and electrically connected to the conductive pattern 200. The stretchable pixel array substrate 10 is used to bond with the light-emitting diode element 230 to form a stretchable display device. For example, in this embodiment, the light-emitting diode element 230 may be electrically connected to the pixel driving circuit PC of the island element IS through the transparent conductive pattern 220 and the conductive pattern 200, but the present invention is not limited thereto.

[0029] Referring to Figures 1, 2 and 3, in this embodiment, each island element IS may be provided with a plurality of light-emitting diode elements 230 that emit a first color light, a second color light and a third color light respectively; the first color light, the second color light and the third color light are, for example, red light, green light and blue light respectively; but the present invention is not limited thereto.

[0030] Refer to Figures 1 and 3. In this embodiment, the auxiliary pattern 170 is disposed between the conductor 186 and at least a portion of the upper surface ISb of the island element IS. The auxiliary pattern 170 is further disposed between the conductor 186 and at least a portion of the sidewall ISa of the island element IS. The auxiliary pattern 170 is further disposed between the conductor 186 and the line area 114 of the substrate 110.

[0031] Figure 4 is a top view of the auxiliary pattern 170 and the wire 186 of the stretchable pixel array substrate 10 according to an embodiment of the present invention.

[0032] Referring to Figures 1, 3, and 4, in this embodiment, the vertical projection area of ​​a portion of the conductor 186 on the pixel area 112 of the substrate 110 is less than or equal to the vertical projection area of ​​a portion of the auxiliary pattern 170 on the pixel area 112 of the substrate 110. In this embodiment, within the pixel area 112, except for the area where the conductor 186 contacts the island element IS (i.e., where the contact window 174 is located), the vertical projection of the conductor 186 on the substrate 110 falls within the vertical projection of the auxiliary pattern 170 on the substrate 110.

[0033] Figure 5 illustrates the relationship between the thickness T170 of the auxiliary pattern 170 disposed on a portion of the upper surface ISb of the island element IS and the strain of the island element IS at the end of the conductor 186 according to an embodiment of the present invention. Referring to Figures 3 and 5, the data in Figure 5 shows that in this embodiment, the Young's modulus of the auxiliary pattern 170 is preferably less than 10 GPa, but the present invention is not limited thereto. The data in Figure 5 shows that as the thickness T170 of the auxiliary pattern 170 on the island element IS increases, the stress at the end of the conductor 186 on the island element IS decreases. Considering process capability and material properties, in this embodiment, the thickness T170 of the auxiliary pattern 170 is preferably less than 10 μm, but the present invention is not limited thereto.

[0034] Referring to Figure 3, the auxiliary pattern 170 has an extension length L170 on the upper surface ISb of the island element IS. Figure 6 shows the relationship between the overall strain of the stretchable pixel array substrate 10 and the strain of the island element IS under various extension lengths L170. Referring to Figures 3 and 6, the data in Figure 6 shows that the longer the extension length L170 of the auxiliary pattern 170, the smaller the strain of the island element IS. When the overall strain of the stretchable pixel array substrate 10 increases, the island element IS will also be subjected to a larger strain. At this time, the strain can be reduced by increasing the extension length L170 of the auxiliary pattern 170 (or, increasing the length of the wire 186 extending into the island element IS).

[0035] The difference between the stretchable pixel array substrate of a comparative example (not shown) and the stretchable pixel array substrate 10 of an embodiment of the present invention is that the stretchable pixel array substrate of the comparative example does not include the auxiliary pattern 170. The stretchable pixel array substrate of the comparative example experiences a strain of 0.94% at the junction of the island element IS and the conductor 186, which is close to the edge of damage, making the overall structure unable to withstand greater stretching. By adding the auxiliary pattern 170, the stretchable pixel array substrate 10 of an embodiment of the present invention can reduce the strain at the junction of the island element IS and the conductor 186 to 0.47%. Compared with the stretchable pixel array substrate of the comparative example, the stretchable pixel array substrate 10 of an embodiment of the present invention reduces the strain at the junction of the island element IS and the conductor 186 by approximately 50%.

[0036] It must be noted that the following embodiments use the component reference numerals and some content of the foregoing embodiments, wherein the same reference numerals are used to represent the same or similar components, and the description of the same technical content is omitted. For the description of the omitted parts, please refer to the foregoing embodiments, and the following embodiments will not repeat them.

[0037] Figure 7 is a schematic diagram of the island element IS, auxiliary pattern 170A and light-emitting diode element 230 of a stretchable pixel array substrate 10A according to another embodiment of the present invention.

[0038] The stretchable pixel array substrate 10A in FIG7 is similar to the aforementioned stretchable pixel array substrate 10, except that the auxiliary patterns 170A and 170 are different. Referring to FIG7, specifically, in this embodiment, the upper surface ISb of the island element IS and the sidewall ISa of the island element IS have a junction i. The junction i includes a plurality of side edges i1 and a plurality of corners i2 disposed between the plurality of side edges i1. The auxiliary pattern 170A includes a plurality of auxiliary parts 170A-1 that are separated from each other. The plurality of auxiliary parts 170A-1 respectively cross the plurality of side edges i1 of the junction i, and the plurality of corners i2 of the junction i are located between the plurality of auxiliary parts 170A-1.

[0039] Figure 8 is a schematic diagram of the island element IS, auxiliary pattern 170B, and light-emitting diode element 230 of the stretchable pixel array substrate 10B according to another embodiment of the present invention. Figure 9 is a cross-sectional schematic diagram of the stretchable pixel array substrate 10B according to another embodiment of the present invention. Figure 9 corresponds to section line II-II' of Figure 8.

[0040] The stretchable pixel array substrate 10B of this embodiment is similar to the stretchable pixel array substrate 10 described above. The difference between the two is that the auxiliary patterns 170B and 170 are different. Referring to Figures 8 and 9, specifically, in this embodiment, the peripheral area ISb-2 of the upper surface ISb of the island element IS has multiple side sub-areas ISb-2a and multiple corner sub-areas ISb-2b disposed between the multiple side sub-areas ISb-2a; the auxiliary pattern 170B covers the multiple first portions ISa-1 of the sidewall ISa of the island element IS that are connected to the multiple side sub-areas ISb-2a, the multiple side sub-areas ISb-2a of the upper surface ISb of the island element IS, and the middle area ISb-1 of the upper surface ISb of the island element IS; the auxiliary pattern 170B has multiple notches 176, which respectively overlap the multiple corner sub-areas ISb-2b of the upper surface ISb of the island element IS and the multiple second portions ISa-2 of the sidewall ISa of the island element IS that are connected to the multiple corner sub-areas ISb-2b.

[0041] FIG10 is a schematic diagram of the island element IS, auxiliary pattern 170C and light-emitting diode element 230 of the stretchable pixel array substrate 10C according to another embodiment of the present invention. FIG11 is a cross-sectional schematic diagram of the stretchable pixel array substrate 10C according to another embodiment of the present invention. FIG11 corresponds to section line III-III' of FIG10.

[0042] The stretchable pixel array substrate 10C of this embodiment is similar to the aforementioned stretchable pixel array substrate 10, except that the auxiliary patterns 170 and 170C are different. Referring to Figures 10 and 11, specifically, in this embodiment, except that the auxiliary pattern 170C requires the conductor 186 to pass through the area connected to the island element IS (i.e., the contact window 174), the auxiliary pattern 170C covers the remaining area of ​​the island element IS.

Claims

1. A stretchable pixel array substrate, comprising: A substrate having a plurality of pixel areas and a circuit area, wherein the circuit area is located between and connected to the pixel areas; a plurality of island elements respectively disposed on the pixel areas of the substrate, wherein each island element includes a pixel driving circuit and has a sidewall; an auxiliary pattern disposed on the circuit area of ​​the substrate and extending at least to at least a portion of one of the pixel areas, wherein the auxiliary pattern covers at least a portion of the sidewall of the island element and at least a portion of an upper surface of the island element facing away from the substrate; a conductor disposed on the auxiliary pattern and electrically connected to the plurality of pixel driving circuits of the island elements; and an insulating layer covering the conductor and the island elements; wherein the auxiliary pattern has a contact window, the contact window of the auxiliary pattern overlapping the at least a portion of the upper surface of the island element facing away from the substrate, and the conductor is electrically connected to one of the pixel driving circuits of the island elements through the contact window of the auxiliary pattern.

2. The stretchable pixel array substrate as claimed in claim 1, wherein the auxiliary pattern is disposed between the conductor and at least a portion of the upper surface of the island element, the auxiliary pattern is disposed between the conductor and at least a portion of the sidewall of the island element, and the auxiliary pattern is disposed between the conductor and the line area of ​​the substrate.

3. The stretchable pixel array substrate as claimed in claim 1, wherein the vertical projection area of ​​a portion of the conductor on the pixel region of the substrate is less than or equal to the vertical projection area of ​​a portion of the auxiliary pattern on the pixel region of the substrate.

4. The stretchable pixel array substrate as claimed in claim 1, wherein the Young's modulus of the auxiliary pattern is less than 10 GPa.

5. The stretchable pixel array substrate as claimed in claim 1, wherein the auxiliary pattern disposed on a portion of the upper surface of the island element has a thickness less than 10 μm.

6. The stretchable pixel array substrate as claimed in claim 1, wherein the upper surface of the island element includes a peripheral region and a central region, the peripheral region of the upper surface of the island element is connected between the sidewall of the island element and the central region of the upper surface of the island element, the auxiliary pattern covers the sidewall of the island element and the peripheral region of the upper surface of the island element, and the auxiliary pattern has an opening overlapping the central region of the upper surface of the island element.

7. The stretchable pixel array substrate as claimed in claim 1, wherein the upper surface of the island element and the sidewall of the island element have a boundary, the boundary including a plurality of side edges and a plurality of corners disposed between the side edges; the auxiliary pattern includes a plurality of auxiliary portions separated from each other, the auxiliary portions respectively crossing the side edges of the boundary, and the corners of the boundary located between the auxiliary portions of the auxiliary pattern.

8. The stretchable pixel array substrate as claimed in claim 1, wherein the upper surface of the island element includes a peripheral region and a central region, the peripheral region of the upper surface of the island element is connected between the sidewall of the island element and the central region of the upper surface of the island element, and the peripheral region of the upper surface of the island element has a plurality of side sub-regions and a plurality of corner sub-regions disposed between the side sub-regions; the auxiliary pattern covers a plurality of first portions of the sidewall of the island element connected to the side sub-regions, the side sub-regions of the upper surface of the island element, and the central region of the upper surface of the island element; the auxiliary pattern has a plurality of notches, which respectively overlap the corner sub-regions of the upper surface of the island element and the plurality of second portions of the sidewall of the island element connected to the corner sub-regions.

Images