STRETCHABLE DISPLAY BACKGROUNDS AND THE METHODS FOR MANUFACTURING THEM, AND DISPLAY EQUIPMENT

Abstract

The invention relates to a stretchable display substrate and a method for producing such substrates, and a display device. The stretchable display substrate comprises a number of perforated regions; a substrate; a pixel block made up on the substrate; a signal path made up on the substrate and electrically connected to the pixel block; and a number of inorganic insulators stacked on the substrate, at least one of which has a first void located near the perforated regions, and the orthogonal projection of the first void on the substrate does not overlap the orthogonal projections of the signal path and the pixel block on the substrate.

Description

A stretchable display substrate and its preparation method, and a display device Technical Field

[0001] The present disclosure relates to the field of display technology, and in particular to a stretchable display substrate, a preparation method thereof, and a display device. Background Art

[0002] With the development of display technology, organic light-emitting diodes (OLEDs), capable of flexible displays, have promoted display diversification and gradually become the mainstream of display technology. In some related technologies, OLED flexible display devices can meet the requirements of two-dimensional bending, but are not suitable for the flexibility required for stretchable display substrates in more complex display devices (such as wearable devices).

[0003] In order to develop stretchable OLED display functions, some related technologies open holes in the substrate material of the OLED flexible display device to form islands for preparing pixel areas and bridges for routing, and the display device is stretched by deforming the bridges.

[0004] Summary of the Invention

[0005] An embodiment of the present disclosure provides a stretchable display substrate, comprising a plurality of hole areas; the stretchable display substrate comprises:

[0006] substrate;

[0007] A pixel unit is provided on the substrate;

[0008] a signal line, disposed on the substrate and electrically connected to the pixel unit;

[0009] A plurality of inorganic insulating layers are stacked on the substrate, at least one of the plurality of inorganic insulating layers has a first hollow portion near the hole area, and the orthographic projection of the first hollow portion on the substrate does not overlap with the orthographic projection of the signal line and the pixel unit on the substrate.

[0010] Optionally, the stretchable display substrate provided in the embodiment of the present disclosure further comprises: a plurality of pixel island regions spaced apart between the hole regions, and a connecting bridge region between the pixel island regions and the hole regions;

[0011] The connecting bridge area includes at least one pixel unit, the first hollow portion is located in the connecting bridge area, and the first hollow portion is located between the pixel unit in the connecting bridge area and the hole area.

[0012] Optionally, in the above-mentioned stretchable display substrate provided in an embodiment of the present disclosure, the connecting bridge area includes a plurality of the pixel units, and the orthographic projection of the signal line on the substrate is at least located within the pixel units of the connecting bridge area and the orthographic projection of the area between the pixel units of the connecting bridge area on the substrate.

[0013] Optionally, in the above-mentioned stretchable display substrate provided in an embodiment of the present disclosure, an extension direction of the first hollow portion is substantially the same as an edge of the hole area.

[0014] Optionally, in the above-mentioned stretchable display substrate provided in an embodiment of the present disclosure, the first hollow portion is not connected to the hole area.

[0015] Optionally, in the above-mentioned stretchable display substrate provided in an embodiment of the present disclosure, a distance between a side wall of the first hollow portion close to the hole area and a side wall of the hole area close to the first hollow portion is greater than or equal to 2 μm.

[0016] Optionally, in the above-mentioned stretchable display substrate provided in an embodiment of the present disclosure, a width of the first hollow portion is greater than or equal to 5 um in a direction from the pixel island area to the hole area.

[0017] Optionally, in the above-mentioned stretchable display substrate provided in an embodiment of the present disclosure, the first hollow portion and the hole area are interconnected.

[0018] Optionally, in the above-mentioned stretchable display substrate provided in an embodiment of the present disclosure, an edge of the first hollow portion close to the hole area overlaps with an edge of the hole area close to the first hollow portion.

[0019] Optionally, in the above-mentioned stretchable display substrate provided in an embodiment of the present disclosure, the pixel unit includes at least one sub-pixel, the sub-pixel includes a pixel circuit and a light-emitting device, the light-emitting device includes a stacked anode, an organic light-emitting layer, and a cathode; a partition structure is provided in the connection bridge region near the pixel unit, the organic light-emitting layer is disconnected at the partition structure, and the cathode is disconnected at the partition structure;

[0020] A distance between a side wall of the first hollow portion close to the pixel unit and the partition structure is greater than or equal to 2 μm.

[0021] Optionally, in the above-mentioned stretchable display substrate provided in an embodiment of the present disclosure, the first hollow portion is a closed structure arranged around the hole area.

[0022] Optionally, in the above-mentioned stretchable display substrate provided in an embodiment of the present disclosure, the partition structure is a closed structure arranged around the first hollow portion.

[0023] Optionally, in the above-mentioned stretchable display substrate provided in an embodiment of the present disclosure, a portion of the hole area includes: a first sub-hole area and a second sub-hole area extending along the first direction and arranged along the second direction, and a third sub-hole area extending along the second direction; another portion of the hole area includes: a fourth sub-hole area and a fifth sub-hole area extending along the second direction and arranged along the first direction, and a sixth sub-hole area extending along the first direction; the first direction and the second direction are approximately perpendicular, the third sub-hole area approximately connects the central areas of the first sub-hole area and the second sub-hole area, and the sixth sub-hole area approximately connects the central areas of the fourth sub-hole area and the fifth sub-hole area;

[0024] The first hollow portion is at least arranged at at least one of the following positions: one side of the connection position between the first sub-hole area and the third sub-hole area, one side of the connection position between the second sub-hole area and the third sub-hole area, one side of the end of the first sub-hole area and one side of the end of the second sub-hole area, one side of the connection position between the fourth sub-hole area and the sixth sub-hole area, one side of the connection position between the fifth sub-hole area and the sixth sub-hole area, one side of the end of the fourth sub-hole area and one side of the end of the fifth sub-hole area.

[0025] Optionally, in the above-mentioned stretchable display substrate provided in the embodiment of the present disclosure, the first hollow portion is provided on one side of the connection position between the first sub-hole area and the third sub-hole area, on one side of the connection position between the second sub-hole area and the third sub-hole area, on one side of the end of the first sub-hole area and on one side of the end of the second sub-hole area, on one side of the connection position between the fourth sub-hole area and the sixth sub-hole area, on one side of the connection position between the fifth sub-hole area and the sixth sub-hole area, on one side of the end of the fourth sub-hole area and on one side of the end of the fifth sub-hole area.

[0026] Optionally, in the above-mentioned stretchable display substrate provided in an embodiment of the present disclosure, the pixel island area includes at least one pixel unit, and the pixel resolution of the pixel island area is substantially the same as the pixel resolution of the connecting bridge area.

[0027] Optionally, in the above-mentioned stretchable display substrate provided in an embodiment of the present disclosure, the multiple inorganic insulating layers include a first barrier layer, a buffer layer, a first gate insulating layer, a second gate insulating layer, an interlayer dielectric layer, a first passivation layer, a second passivation layer and an inorganic encapsulation layer stacked on the substrate, and the first hollow portion is set in at least one of the first barrier layer, the buffer layer, the first gate insulating layer, the second gate insulating layer, the interlayer dielectric layer, the first passivation layer, the second passivation layer and the inorganic encapsulation layer.

[0028] Optionally, in the above-mentioned stretchable display substrate provided in an embodiment of the present disclosure, the interlayer dielectric layer, the first passivation layer, the second passivation layer and the inorganic encapsulation layer are all provided with the first hollow portions, and the first hollow portions substantially overlap.

[0029] Optionally, in the above-mentioned stretchable display substrate provided by an embodiment of the present disclosure, the inorganic encapsulation layer includes a first inorganic layer and a second inorganic layer stacked on the second passivation layer;

[0030] The stretchable display substrate further includes: a first planarization layer and a second planarization layer located between the interlayer dielectric layer and the first passivation layer, a pixel definition layer located between the second passivation layer and the inorganic encapsulation layer, and an organic layer located between the first inorganic layer and the second inorganic layer;

[0031] At least one of the first planar layer, the second planar layer, the pixel defining layer, and the organic layer has a second hollow portion near the hole region, and the first hollow portion and the second hollow portion substantially overlap.

[0032] Optionally, in the above-mentioned stretchable display substrate provided in an embodiment of the present disclosure, the base includes a flexible layer, or the base includes a first flexible layer, a second barrier layer and a second flexible layer stacked on the side of the first barrier layer away from the buffer layer.

[0033] Correspondingly, an embodiment of the present disclosure further provides a display device comprising the above-mentioned stretchable display substrate.

[0034] Accordingly, an embodiment of the present disclosure further provides a method for preparing the above-mentioned stretchable display substrate, comprising:

[0035] providing a substrate;

[0036] forming pixel units and signal lines electrically connected to the pixel units on the substrate;

[0037] A plurality of inorganic insulating layers are stacked on the substrate; wherein at least one of the plurality of inorganic insulating layers has a first hollow portion near the hole area, and the orthographic projection of the first hollow portion on the substrate does not overlap with the orthographic projection of the signal line and the pixel unit on the substrate.

[0038] Optionally, in the above-mentioned preparation method provided by the embodiment of the present disclosure, at least one layer of the plurality of inorganic insulating layers has a first hollow portion near the hole area, specifically comprising:

[0039] Depositing a first barrier layer, a buffer layer, a first gate insulating layer, a second gate insulating layer, an interlayer dielectric layer, a first passivation layer, a second passivation layer and an inorganic encapsulation layer on the substrate;

[0040] The first hollow portion is formed in at least one of the first barrier layer, the buffer layer, the first gate insulating layer, the second gate insulating layer, the interlayer dielectric layer, the first passivation layer, the second passivation layer and the inorganic encapsulation layer by using a patterning process. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] FIG1 is a schematic top view of a stretchable display substrate provided in an embodiment of the present disclosure;

[0042] FIG2 is a schematic top view of another stretchable display substrate provided by an embodiment of the present disclosure;

[0043] FIG3 is a schematic cross-sectional view along the AA′ direction in FIG1 ;

[0044] FIG4 is a schematic cross-sectional view along the AA′ direction in FIG2 ;

[0045] FIG5 is a flow chart of a method for manufacturing a stretchable display substrate provided by an embodiment of the present disclosure;

[0046] FIG6 is a flow chart of a method for manufacturing another stretchable display substrate provided in an embodiment of the present disclosure;

[0047] 7A-7K are schematic structural diagrams of executing each step of the method for manufacturing a stretchable display substrate provided by an embodiment of the present disclosure. DETAILED DESCRIPTION

[0048] In order to make the purpose, technical solutions and advantages of the present disclosure more clear, the specific implementation of the method for manufacturing a stretchable display substrate provided by the embodiment of the present disclosure is described in detail below with reference to the accompanying drawings. It should be understood that the preferred embodiments described below are only used to illustrate and explain the present disclosure and are not intended to limit the present disclosure. In addition, the embodiments and features in the embodiments of this application can be combined with each other if there is no conflict.

[0049] The thickness, size and shape of each film layer in the accompanying drawings do not reflect the actual proportion of the stretchable display substrate, and the purpose is only to illustrate the content of the present disclosure.

[0050] An embodiment of the present disclosure provides a stretchable display substrate, as shown in FIG1 and FIG2 , including a plurality of hole regions Q2 ; specifically, the hole regions Q2 are used to provide deformation space for the display substrate when stretched.

[0051] Specifically, as shown in FIG3 and FIG4, FIG3 is a schematic cross-sectional view of the structure of FIG1 along the AA' direction, and FIG4 is a schematic cross-sectional view of the structure of FIG2 along the AA' direction. The stretchable display substrate includes:

[0052] Substrate 1; Substrate 1 may be a flexible substrate, enabling the stretchable region of the stretchable display substrate to be stretchable;

[0053] A pixel unit 4 is provided on the substrate 1;

[0054] The signal line 2 is provided on the substrate 1 and is electrically connected to the pixel unit 4; specifically, the signal line 2 may include a gate line, a data line, etc.;

[0055] Multiple inorganic insulating layers are stacked on a substrate 1, and at least one of the multiple inorganic insulating layers has a first hollow portion 3 near the hole area Q2. The orthographic projection of the first hollow portion 3 on the substrate 1 does not overlap with the orthographic projection of the signal line 2 and the pixel unit 4 on the substrate 1.

[0056] The above-mentioned stretchable display substrate provided by the embodiment of the present disclosure is subjected to tension and deformed at a position near the hole area Q2 when stretched. The present disclosure provides at least one layer of the multiple inorganic insulating layers with a first hollow portion 3 near the hole area Q2, that is, by removing at least one layer of the multiple inorganic insulating layers at a position near the hole area Q2. In this way, the buckling deformation behavior of the position near the hole area Q2 when stretched can be improved, so that the position near the hole area Q2 is not prone to breakage and the pixel unit 4 is not easily damaged, thereby improving the stretching performance of the stretchable display substrate.

[0057] It should be noted that, as shown in Figures 1 and 2, the hole area Q2 in the embodiment of the present disclosure can completely penetrate the stretchable display substrate. Of course, the hole area Q2 can also penetrate all the film layers on the base of the stretchable display substrate and part of the base.

[0058] It should be noted that, as shown in Figures 3 and 4, the embodiment of the present disclosure is schematically illustrated by taking the example of removing all inorganic insulating layers located on the substrate 1 to form the first hollow portion 3. Of course, only any one layer of the inorganic insulating layer or multiple layers of inorganic insulating layers can be removed to form the first hollow portion 3.

[0059] In specific implementations, stretchable panels with island-bridge structures in related technologies face problems such as low display resolution (PPI) and uneven display. In order to improve display resolution and alleviate the problem of uneven display, the stretchable display substrate provided in the embodiments of the present disclosure, as shown in Figures 1-4, further includes: a plurality of pixel islands Q1 spaced apart between the hole areas Q2, and a connecting bridge area Q3 between the pixel islands Q1 and the hole areas Q2. Specifically, the pixel islands Q1 are used to display images, and the connecting bridge area Q3 is used for routing (to connect signals between adjacent pixel islands Q1) and transmitting tension.

[0060] The connecting bridge area Q3 includes at least one pixel unit 4, and the first hollow portion 3 is located in the connecting bridge area Q3, and the first hollow portion 3 is located between the pixel unit 4 in the connecting bridge area Q3 and the hole area Q2; that is, the present disclosure expands the original arrangement of pixel units only in the pixel island area Q1 to also arrange pixel units in the connecting bridge area Q3, thereby improving the display resolution and improving the problem of uneven display.

[0061] As shown in Figures 1-4 , the connection bridge area Q3 may include multiple pixel units 4, and the orthographic projection of the signal line 2 on the substrate 1 is located at least within the orthographic projection of the pixel units 4 in the connection bridge area Q3 and the area between the pixel units 4 in the connection bridge area Q3 on the substrate 1. In other words, the signal line 2 is routed below the pixel units 4 in the connection bridge area Q3 and in the area between the pixel units 4, thereby achieving electrical connection between the pixel units 4.

[0062] In a specific implementation, in the stretchable display substrate provided by the embodiment of the present disclosure, as shown in FIG1 , the extension direction of the first hollow portion 3 is substantially the same as the edge of the hole region Q2. Thus, the first hollow portion 3 surrounding the hole region Q2 is provided around the hole region Q2, further improving the stretchability of the stretchable display substrate.

[0063] In a specific implementation, in the stretchable display substrate provided in the embodiment of the present disclosure, as shown in Figure 3, the first hollow portion 3 is not connected to the hole area Q2. Since the first hollow portion 3 is formed in at least one layer of the multiple inorganic insulating layers, that is, multiple inorganic insulating layers are retained between the first hollow portion 3 and the hole area Q2, at least one layer of inorganic insulating layer is removed in the connecting bridge area Q3 to form the first hollow portion 3, thereby improving the buckling deformation behavior of the connecting bridge area Q3 when stretched, making it less likely for the connecting bridge area Q3 to break and the pixel island area Q1 adjacent to the connecting bridge area Q3 to be damaged, thereby improving the stretchability of the stretchable display substrate.

[0064] In a specific implementation, in the stretchable display substrate provided in the embodiment of the present disclosure, as shown in Figure 3, the distance between the side wall of the first hollow portion 3 close to the hole area Q2 and the side wall of the hole area Q2 close to the first hollow portion 3 (this distance is the width of the inorganic insulating layer between the hole area Q2 and the first hollow portion 3) is greater than or equal to 2μm.

[0065] In the specific implementation, in order to reduce the difficulty of the manufacturing process, in the stretchable display substrate provided in the embodiment of the present disclosure, as shown in Figure 3, the width of the first hollow portion 3 is greater than or equal to 5um in the direction from the pixel island area Q1 to the hole area Q2. In this way, when the exposure, development and etching process is used to remove each inorganic insulating layer, the difficulty of the exposure, development and etching process can be reduced.

[0066] In a specific implementation, in the stretchable display substrate provided in the embodiment of the present disclosure, as shown in FIG4 , the first hollow portion 3 is interconnected with the hole area Q2, that is, when etching each inorganic insulating layer in the connecting bridge area Q3, the inorganic insulating layer in the connecting bridge area Q3 is directly etched to be connected with the hole area Q2, thereby further reducing the inorganic insulating layer in the connecting bridge area Q3, thereby further improving the stretchability of the connecting bridge area Q3.

[0067] In a specific implementation, in the stretchable display substrate provided by the embodiment of the present disclosure, as shown in FIG4 , the edge of the first hollow portion 3 near the hole region Q2 overlaps with the edge of the hole region Q2 near the first hollow portion 3. That is, no inorganic insulating layer is retained between the first hollow portion 3 and the hole region Q2. Specifically, when etching the inorganic insulating layers in the connecting bridge region Q3, the inorganic insulating layer in the area corresponding to the first hollow portion 3 is directly etched to the edge of the hole region Q2, further reducing the inorganic insulating layer in the connecting bridge region Q3, thereby further improving the stretchability of the connecting bridge region Q3.

[0068] In a specific implementation, in the stretchable display substrate provided in the embodiment of the present disclosure, as shown in Figures 3 and 4, the pixel unit 4 includes at least one sub-pixel, the sub-pixel includes a pixel circuit and a light-emitting device, the pixel circuit is located between the light-emitting device and the substrate 1, and the light-emitting device includes a stacked anode 6, an organic light-emitting layer 7 and a cathode 8; a partition structure 9 is provided near the pixel unit 4 in the connecting bridge area Q3, and the partition structure 9 is provided around the first hollow portion 3 in Figures 1 and 2, that is, the partition structure 9 is located between the pixel unit 4 and the first hollow portion 3, the organic light-emitting layer 7 is disconnected at the partition structure 9, and the cathode 8 is disconnected at the partition structure 9; due to the partition structure 9 Located in the connecting bridge area Q3, and because the connecting bridge area Q3 is located between the hole area Q2 and the pixel island area Q1, that is, the organic light-emitting layer 7 and the cathode 8 separated by the partition structure 9 are partially located in the pixel island area Q1, and partially close to the hole area Q2. The organic light-emitting layer 7 and the cathode 8 close to the hole area Q2 are easily invaded by water and oxygen. By dividing the organic light-emitting layer 7 and the cathode 8 into two mutually isolated parts, the isolation path distance of the water and oxygen invading the organic light-emitting layer 7 and the cathode 8 in the sub-pixel through the organic light-emitting layer 7 and the cathode 8 close to the hole area Q2 is effectively extended, that is, it is ensured that water and oxygen cannot invade the organic light-emitting layer 7 and the cathode 8 in the sub-pixel, thereby ensuring the normal display of the display product.

[0069] Light-emitting devices can include red (R) devices that emit red light, green (G) devices that emit green light, and blue (B) devices that emit blue light. Light-emitting devices can be inorganic light-emitting diodes, organic light-emitting diodes (OLEDs) made from organic materials, micro light-emitting diodes (Micro LEDs), or mini light-emitting diodes (Mini LEDs). Micro LEDs are ultra-small inorganic light-emitting elements under 100 microns in size that emit light without a backlight or filter.

[0070] The pixel circuit can adopt a variety of structures. For example, the pixel circuit can include a structure of 2 transistors and 1 capacitor (2T1C), a structure of 7 transistors and 1 capacitor (7T1C), or a structure of 12 transistors and 1 capacitor (12T1C). The pixel circuit generally includes a driving transistor and the remaining switching transistors. As shown in Figures 3 and 4, schematic diagrams of the driving transistor, light-emitting device and storage capacitor in the pixel circuit are shown. The driving transistor can be a top-gate type, including an active layer 21, a first gate insulating layer 22, a gate 23, a second gate insulating layer 24, an interlayer dielectric layer 25, a source 26, and a drain 27 stacked on a substrate 1. Specifically, the active layer 21 can be formed on the buffer layer 28, which is disposed on the first barrier layer 29. The first gate insulating layer 22 covers the buffer layer 28 and the active layer 21. The gate 23 is formed on the side of the first gate insulating layer 22 facing away from the active layer 21. The second gate insulating layer 24 covers the gate 23 and the first gate insulating layer 22. The interlayer dielectric layer 25 covers the second gate insulating layer 24. The source 26 and the drain 27 are formed on the side of the interlayer dielectric layer 25 facing away from the substrate 1 and are respectively located on opposite sides of the gate 23. The source 26 and the drain 27 can respectively contact the opposite sides of the active layer 21 through vias. As shown in Figures 3 and 4, the capacitor structure (for example, the storage capacitor Cst in the pixel circuit) can include a first plate C1 and a second plate C2. The second plate C2 is disposed in the same layer as the gate 23. The first plate C1 is located between the second gate insulating layer 24 and the interlayer dielectric layer 25, and the first plate C1 is disposed opposite the second plate C2.

[0071] Specifically, as shown in Figures 3 and 4, the signal line 2 located in the connection bridge region Q3 is arranged in the film layer where the source electrode 26 and the drain electrode 27 are located. The anode 6 and the drain electrode 27 of the light-emitting device can be electrically connected directly (i.e., a single-layer SD structure) or electrically connected via a strapping electrode 30 located therebetween (i.e., a double-layer SD structure). A first flat layer 31 is provided between the strapping electrode 30 and the drain electrode 27, and a second flat layer 32, a first passivation layer 33, and a second passivation layer 34 are provided between the strapping electrode 30 and the anode 6. Each light-emitting device in the stretchable display substrate is generally defined by a pixel defining layer 35, which has an opening area that exposes the light-emitting device.

[0072] In the stretchable display substrate provided in the embodiment of the present disclosure, the base may include a flexible layer, or as shown in Figures 3 and 4, the base 1 includes a first flexible layer 11, a second barrier layer 12, and a second flexible layer 13 stacked on the side of the first barrier layer 29 away from the buffer layer 28.

[0073] Specifically, the material of the flexible layer may be polyimide (PI), polyester, polyamide, or the like.

[0074] Specifically, as shown in FIG3 and FIG4 , the base 1 can be disposed on a glass substrate 10 to facilitate subsequent peeling.

[0075] Specifically, as shown in Figures 3 and 4, the distance between the side wall of the first hollow portion 3 close to the pixel unit 4 and the partition structure 9 (that is, the width of the inorganic insulating layer between the first hollow portion 3 and the partition structure 9) can be greater than or equal to 2um, the organic light-emitting layer 7 is disconnected at the partition structure 9, and the cathode 8 is disconnected at the partition structure 9.

[0076] In a specific implementation, in the stretchable display substrate provided in the embodiment of the present disclosure, as shown in FIG1 , the first hollow portion 3 is a closed structure arranged around the hole area Q2, so that the inorganic insulating layer of the connecting bridge area Q3 can be removed as much as possible, thereby maximizing the stretchability of the connecting bridge area.

[0077] In specific implementation, since water and oxygen can easily invade into the pixel unit from the hole area, in order to block the water and oxygen intrusion paths at various positions in the hole area, in the stretchable display substrate provided in the embodiment of the present disclosure, as shown in Figure 3, the partition structure 9 is a closed structure arranged around the first hollow portion 3, that is, the positive projection pattern of the partition structure 9 on the substrate 1 is the same as the boundary pattern of the hole area Q2, that is, the partition structure 9 is arranged around the hole area Q2, thereby ensuring that the partition structure 9 prevents water and oxygen from invading the pixel island area Q1 from the hole area Q2 at various positions.

[0078] In a specific implementation, in the stretchable display substrate provided by the embodiment of the present disclosure, as shown in FIG2 , a portion of the hole area Q2 includes: a first sub-hole area Q21 and a second sub-hole area Q22 extending along the first direction X and arranged along the second direction Y, and a third sub-hole area Q23 extending along the second direction Y; another portion of the hole area Q2 includes: a fourth sub-hole area Q24 and a fifth sub-hole area (not shown) extending along the second direction Y and arranged along the first direction X, and a sixth sub-hole area Q26 extending along the first direction X; the first direction X and the second direction Y are substantially perpendicular, and the sixth sub-hole area Q26 substantially connects the central areas of the fourth sub-hole area Q24 and the fifth sub-hole area;

[0079] When the stretchable display substrate is stretched, as shown in FIG2 , one side (corner) of the connection position between the first sub-hole area Q21 and the third sub-hole area Q23, one side (corner) of the connection position between the second sub-hole area Q22 and the third sub-hole area Q23, one side of the end of the first sub-hole area Q21 and one side of the end of the second sub-hole area Q22, one side (corner) of the connection position between the fourth sub-hole area Q24 and the sixth sub-hole area Q26, one side of the connection position between the fifth sub-hole area and the sixth sub-hole area Q26, one side of the end of the fourth sub-hole area Q24 and one side of the end of the fifth sub-hole area are all stress concentration points generated during stretching, and the inorganic The insulating layer breaks first. To prevent the inorganic insulating layer from breaking at these locations, the present disclosure provides a first hollow portion 3 at at least one of the following locations: one side of the connection between the first sub-hole region Q21 and the third sub-hole region Q23, one side of the connection between the second sub-hole region Q22 and the third sub-hole region Q23, one end of the first sub-hole region Q21 and one end of the second sub-hole region Q22, one side of the connection between the fourth sub-hole region Q24 and the sixth sub-hole region Q26, one side of the connection between the fifth sub-hole region and the sixth sub-hole region Q26, one end of the fourth sub-hole region Q24, and one end of the fifth sub-hole region. This reduces the difficulty of fabricating a large-area first hollow portion 3 and avoids the problem of the inorganic insulating layer breaking at the easily breakable locations of the inorganic insulating layer corresponding to the hole region Q2.

[0080] It should be noted that, as shown in Figures 1 and 2, the embodiment of the present disclosure is schematically illustrated by taking the shape of the hole area Q2 as approximately an "I" shape as an example. Of course, the shape of the hole area Q2 is not limited to this, for example, it can also be a "T" shape, an "I" shape, etc.

[0081] Preferably, in the stretchable display substrate provided in the embodiment of the present disclosure, as shown in Figure 2, a first hollow portion 3 is provided on one side of the connection position between the first sub-hole area Q21 and the third sub-hole area Q23, one side of the connection position between the second sub-hole area Q22 and the third sub-hole area Q23, one side of the end of the first sub-hole area Q21 and one side of the end of the second sub-hole area Q22, one side of the connection position between the fourth sub-hole area Q24 and the sixth sub-hole area Q26, one side of the connection position between the fifth sub-hole area and the sixth sub-hole area Q26, one side of the end of the fourth sub-hole area Q24 and one side of the end of the fifth sub-hole area.

[0082] In the stretchable display substrate provided by the present embodiment, as shown in Figures 1 and 2, the pixel island region Q1 includes at least one pixel unit 4. The pixel resolution of the pixel island region Q1 is substantially the same as that of the connecting bridge region Q3. This can improve display resolution and improve display unevenness.

[0083] In the stretchable display substrate provided in the embodiment of the present disclosure, as shown in Figures 3 and 4, the multiple inorganic insulating layers include a first barrier layer 29, a buffer layer 28, a first gate insulating layer 22, a second gate insulating layer 24, an interlayer dielectric layer 25, a first passivation layer 33, a second passivation layer 34 and an inorganic encapsulation layer 36 stacked on a substrate 1, and at least one layer among the first barrier layer 29, the buffer layer 28, the first gate insulating layer 22, the second gate insulating layer 24, the interlayer dielectric layer 25, the first passivation layer 33, the second passivation layer 34 and the inorganic encapsulation layer 36 is provided with a first hollow portion 3.

[0084] In a specific implementation, in the stretchable display substrate provided in the embodiment of the present disclosure, as shown in Figures 3 and 4 , the interlayer dielectric layer 25, the first passivation layer 33, the second passivation layer 34, and the inorganic encapsulation layer 36 are all provided with first hollow portions 3, and the first hollow portions 3 substantially overlap. Of course, in a specific implementation, first hollow portions 3 may also be provided in the first barrier layer 29, the buffer layer 28, the first gate insulating layer 22, and the second gate insulating layer 24.

[0085] It should be noted that, as shown in Figures 3 and 4, the embodiment of the present disclosure is schematically illustrated by providing the first hollow portion 3 in the first barrier layer 29, the buffer layer 28, the first gate insulating layer 22, the second gate insulating layer 24, the interlayer dielectric layer 25, the first passivation layer 33, the second passivation layer 34, and the inorganic encapsulation layer 36. Of course, multiple inorganic insulating layers may be provided with the first hollow portion 3 (i.e., each inorganic insulating layer is etched to hollow out the inorganic insulating layer in the corresponding area). The hollowing process of the multiple inorganic insulating layers may be hollowing out from the topmost inorganic encapsulation layer 36 to any inorganic insulating layer above the second flexible layer 13, for example, directly hollowing out to above the second flexible layer 13, or directly hollowing out to any layer of the first barrier layer 29, the buffer layer 28, the first gate insulating layer 22, the second gate insulating layer 24, the interlayer dielectric layer 25, the first passivation layer 33, the second passivation layer 34, and the inorganic encapsulation layer 36. The first barrier layer 29, buffer layer 28, first gate insulating layer 22, second gate insulating layer 24, and interlayer dielectric layer 25 can be hollowed out through one or two etching processes during the stretchable display substrate fabrication process. Hollowing out the inorganic encapsulation layer 36 is achieved by thinning the inorganic encapsulation layer 36 through a single exposure and etching process after the inorganic encapsulation layer 36 is fabricated. Of course, hollowing out all inorganic insulating layers can also be achieved through a single exposure and deep hole etching process after all inorganic insulating layers are fabricated; the specific etching process can be selected based on actual needs.

[0086] In a specific implementation, in the stretchable display substrate provided by the embodiment of the present disclosure, as shown in FIG3 and FIG4 , the inorganic encapsulation layer 36 includes a first inorganic layer and a second inorganic layer stacked on the second passivation layer 34 ;

[0087] The stretchable display substrate further includes: a first planarization layer 31 and a second planarization layer 32 located between the interlayer dielectric layer 25 and the first passivation layer 33, a pixel defining layer 35 located between the second passivation layer 34 and the inorganic encapsulation layer 36, and an organic layer located between the first inorganic layer and the second inorganic layer;

[0088] At least one of the first planar layer 31 , the second planar layer 32 , the pixel defining layer 35 and the organic layer has a second hollow portion near the hole region Q2 , and the first hollow portion 3 and the second hollow portion substantially overlap.

[0089] It should be understood that the first barrier layer 29, buffer layer 28, first gate insulating layer 22, second gate insulating layer 24, interlayer dielectric layer 25, first passivation layer 33, second passivation layer 34, and inorganic encapsulation layer 36 mentioned in the embodiments of the present disclosure can be made of inorganic insulating materials such as silicon oxide and silicon nitride. The first planarizing layer 31, second planarizing layer 32, pixel defining layer 35, and organic layer can be organic film layers, that is, they can be made of organic insulating materials such as photoresist and PI.

[0090] It should be noted that when all the inorganic insulating layers on the substrate 1 are etched away in the connecting bridge area Q3, the first flat layer 31, the second flat layer 32, the pixel defining layer 35 and the organic layer will also be etched away, that is, a via hole penetrating all the inorganic insulating layers and the organic insulating layers is formed in the connecting bridge area Q3, which can be represented by the first hollow portion 3.

[0091] The inventors of this case tested the stretchable performance of the stretchable display substrate shown in Figure 3 provided by the embodiment of the present disclosure and the stretchable display substrate in the related art that does not have a first hollow portion in the connecting bridge area. The test found that the stretching amount of the present disclosure is approximately 2%, and the stretching amount in the related art is less than 1%. Therefore, the stretchable display substrate provided by the embodiment of the present disclosure significantly improves the stretching performance.

[0092] Based on the same inventive concept, the present disclosure also provides a method for preparing the above-mentioned stretchable display substrate, as shown in FIG5 , comprising:

[0093] S501, providing a substrate;

[0094] S502, forming pixel units and signal lines electrically connected to the pixel units on a substrate;

[0095] S503, forming a plurality of inorganic insulating layers stacked on the substrate; wherein at least one of the plurality of inorganic insulating layers has a first hollow portion near the hole area, and the orthographic projection of the first hollow portion on the substrate does not overlap with the orthographic projection of the signal line and the pixel unit on the substrate.

[0096] In a specific implementation, in the above-mentioned preparation method provided in an embodiment of the present disclosure, at least one layer among the multiple inorganic insulating layers has a first hollow portion near the hole area, as shown in FIG6 , specifically comprising:

[0097] S601, depositing a first barrier layer, a buffer layer, a first gate insulating layer, a second gate insulating layer, an interlayer dielectric layer, a first passivation layer, a second passivation layer and an inorganic encapsulation layer on a substrate;

[0098] S602 , using a patterning process, forming a first hollow portion in at least one of the first barrier layer, the buffer layer, the first gate insulating layer, the second gate insulating layer, the interlayer dielectric layer, the first passivation layer, the second passivation layer, and the inorganic encapsulation layer.

[0099] The process of forming each layer structure in the embodiment of the present disclosure may include a composition process and a photolithography process, among which the composition process may include depositing a film layer, coating a photoresist, mask exposure, development, etching, stripping the photoresist and other processes, while the photolithography process may include coating a film layer, mask exposure, development and other processes. The evaporation, deposition, coating, and coating used are all mature preparation processes in the relevant technology.

[0100] The following details the preparation process of the stretchable display substrate shown in FIG3 , which may include the following steps:

[0101] (1) Taking the substrate 1 as an example, the substrate 1 is divided into a pixel island region Q1, a hole region Q2, and a connecting bridge region Q3. A first flexible layer 11, a second barrier layer 12, and a second flexible layer 13 are sequentially stacked on the glass substrate 10. When forming the second barrier layer 12, the second barrier layer 12 corresponding to the hole region Q2 is etched away. Then, a first barrier layer 29 is formed on the second flexible layer 13, as shown in FIG7A. The material of the flexible layer can be polyimide (PI), polyester, polyamide, etc. The material of the barrier layer can be silicon nitride (SiNx) or silicon oxide (SiOx), etc., to improve the water and oxygen resistance of the substrate.

[0102] (2) A buffer layer 28 is formed on the first barrier layer 29, an active layer thin film is deposited on the buffer layer 28, the active layer thin film is patterned by a patterning process, an active layer 21 is formed on the buffer layer 28, and a first gate insulating layer 22 is formed on the active layer 21, as shown in FIG7B.

[0103] (3) A metal film is deposited on the first gate insulating layer 22 and patterned by a patterning process to form a gate 23, a second electrode C2 and a gate line (not shown) on the first insulating layer 22, as well as a gate connection line (not shown) formed in the connecting bridge region Q3. Subsequently, a second gate insulating layer 24 is formed on the gate 23, as shown in FIG7C .

[0104] (4) A metal film is deposited on the second gate insulating layer 24, and the metal film is patterned by a patterning process to form a first electrode C1 on the second insulating layer 24. The position of the first electrode C1 corresponds to the position of the second electrode C2. Then, an interlayer dielectric layer 25 is formed on the film layer where the first electrode C1 is located. The first gate insulating layer 22, the second gate insulating layer 24 and the interlayer dielectric layer 25 are patterned to form via holes located above the two ends of the active layer 21, via holes corresponding to the hole area Q2, and a first hollow portion 3 located corresponding to the connecting bridge area Q3, as shown in FIG7D.

[0105] (5) A metal film (SD1 layer) is deposited on the interlayer dielectric layer 25, and the metal film is patterned by a patterning process to form a source electrode 26, a drain electrode 27 and a signal line 2 (data line) on the interlayer dielectric layer 25. The source electrode 26 and the drain electrode 27 are connected to the active layer 21 through vias penetrating the first gate insulating layer 22, the second gate insulating layer 24 and the interlayer dielectric layer 25, respectively. Then, a flat thin film of organic material is coated on the substrate 1 on which the source electrode 26 and the drain electrode 27 are formed, and a first flat layer 31 is formed by a masking, exposure and development process. The first flat layer 31 corresponding to the position of the source electrode 26, the position of the hole area Q2 and the position of the first hollow portion 3 of the connecting bridge area Q3 are all developed away, as shown in FIG7E.

[0106] (6) Depositing a metal thin film (SD2 layer, or there may be no SD2 layer) on the first flat layer 31, patterning the metal thin film through a patterning process to form a bonding electrode 30 on the first flat layer 31; forming a flat thin film coated with an organic material on the film layer where the bonding electrode 30 is located, and forming a second flat layer 32 through a mask, exposure, and development process, wherein the second flat layer 32 corresponding to the bonding electrode 30 position, the hole area Q2 position, and the first hollow portion 3 position are all developed; then, on the second flat layer An inorganic insulating material is deposited on 32, and then the buffer layer 28 and the first barrier layer 29 of the hole area Q2 are first etched away, as well as the first flexible layer 11 and the second flexible layer 13 of the hole area Q2; the inorganic insulating material, the buffer layer 28 and the first barrier layer 29 at a position corresponding to the first hollow portion 3 are etched away, and the inorganic insulating material, the second flat layer 32 and a portion of the first flat layer 31 at a position corresponding to the partition structure 9 in the connecting bridge area Q3 are etched away. The etched inorganic insulating material forms a first passivation layer 33, as shown in FIG7F.

[0107] (7) An inorganic insulating material is deposited on the first passivation layer 33, and the inorganic insulating material corresponding to the hole area Q2 and the first hollow portion 3 is etched away, as well as the inorganic insulating material and the first passivation layer 33 at the corresponding position of the bonding electrode 30, to form a second passivation layer 34, as shown in FIG7G .

[0108] (8) A conductive film is deposited on the second passivation layer 34 and patterned by a patterning process to form an anode 6. The anode 6 is electrically connected to the bonding electrode 30 through a via hole penetrating the first passivation layer 33 and the second passivation layer 34, as shown in FIG7H . In an exemplary embodiment, the conductive film may be a three-layer stacked structure of a transparent conductive film / metal film / transparent conductive film, wherein the material of the transparent conductive film may be indium tin oxide (ITO) or indium zinc oxide (IZO), and the metal film may be a metal film such as Al, Ag, or Cu.

[0109] (9) A pixel definition film is coated on the anode 6, and a mask, exposure, and development process are performed to form a pixel definition layer 35. A pixel opening is provided on the pixel definition layer 35 of the pixel island region Q1. The pixel definition layer 35 within the pixel opening is developed away, exposing the surface of the anode 6. The pixel definition layer 35 corresponding to the hole region Q2 and the connecting bridge region Q3 is also developed away, as shown in FIG7I.

[0110] (10) An organic light-emitting layer 7 and a cathode 8 are sequentially formed on the pixel defining layer 35. The organic light-emitting layer 7 is formed in the pixel opening of the pixel defining layer 35 and is connected to the anode 6. The organic light-emitting layer 7 and the cathode 8 are respectively disconnected at the position of the partition structure 9, as shown in FIG7J. Specifically, the organic light-emitting layer 6 and the cathode 7 can both be prepared by an evaporation process. The material of the cathode 8 can be any one or more of magnesium (Mg), silver (Ag), aluminum (Al), copper (Cu) and lithium (Li), or an alloy made of any one or more of the above metals.

[0111] (11) An inorganic encapsulation layer 36 is formed on the cathode 8. The inorganic encapsulation layer 36 may include a first inorganic layer, an organic layer, and a second inorganic layer that are stacked. The inorganic encapsulation layer 36, the cathode 8, and the organic light-emitting layer 6 corresponding to the position of the hole area Q2 and the position of the first hollow portion 3 are etched away, as shown in FIG7K , thereby forming the stretchable display substrate shown in FIG3 provided in the embodiment of the present disclosure.

[0112] It should be noted that the embodiment of the present disclosure is described using the preparation method of the stretchable display substrate shown in Figure 3 as an example. The preparation method of the stretchable display substrate shown in Figure 4 is similar to the preparation method shown in Figure 3, with the difference that all the inorganic insulating layers and organic insulating layers between the first hollow portion 3 and the hole area Q2 in Figure 3 are etched away to form a structure in which the first hollow portion 3 and the hole area Q2 are connected. The preparation method shown in Figure 4 will not be described in detail. The etching of the inorganic insulating layer and the organic insulating layer between the first hollow portion 3 and the hole area Q2 is the same as that of other regions, and the film layers can be etched together during etching.

[0113] Finally, the glass substrate 10 below the stretchable display substrate shown in FIG. 3 and FIG. 4 is peeled off from the stretchable display substrate to obtain the stretchable display substrate.

[0114] Based on the same inventive concept, embodiments of the present disclosure also provide a display device comprising any of the aforementioned stretchable display substrates provided in the embodiments of the present disclosure. The display device can be any product or component with a display function, such as a mobile phone, tablet computer, television, monitor, laptop computer, digital photo frame, or navigation system. The implementation of the display device can be referenced to the aforementioned embodiments of the stretchable display substrate, and any repetitive details will not be repeated here.

[0115] The above-mentioned display device can be any product or component with display function, such as an organic light-emitting diode display panel, a quantum dot light-emitting diode display panel, a display module, a curved screen mobile phone, a smart watch, etc.

[0116] The embodiments of the present disclosure provide a stretchable display substrate, a preparation method thereof, and a display device. When the stretchable display substrate is stretched, the connecting bridge area adjacent to the hole area is subjected to tension and deforms. The present disclosure provides at least one layer of a plurality of inorganic insulating layers with a first hollow portion near the hole area in the connecting bridge area, that is, at least one layer of the plurality of inorganic insulating layers is removed at a position near the hole area in the connecting bridge area. This can improve the buckling deformation behavior of the connecting bridge area when stretched, making the connecting bridge area less likely to break and the pixel island area adjacent to the connecting bridge area less likely to be damaged, thereby improving the stretching performance of the stretchable display substrate.

[0117] Obviously, those skilled in the art may make various changes and modifications to the present disclosure without departing from the spirit and scope of the present disclosure. Thus, if these modifications and variations of the present disclosure fall within the scope of the claims of the present disclosure and their equivalents, the present disclosure is intended to include these modifications and variations.

Claims

1. A stretchable display substrate, wherein: Comprising a plurality of hole areas; the stretchable display substrate comprises: substrate; A pixel unit is provided on the substrate; a signal line, disposed on the substrate and electrically connected to the pixel unit; A plurality of inorganic insulating layers are stacked on the substrate, at least one of the plurality of inorganic insulating layers has a first hollow portion near the hole area, and the orthographic projection of the first hollow portion on the substrate does not overlap with the orthographic projection of the signal line and the pixel unit on the substrate.

2. The stretchable display substrate according to claim 1, wherein: Also includes: a plurality of pixel island regions spaced apart between the hole regions, and a connecting bridge region between the pixel island regions and the hole regions; The connecting bridge area includes at least one pixel unit, the first hollow portion is located in the connecting bridge area, and the first hollow portion is located between the pixel unit in the connecting bridge area and the hole area.

3. The stretchable display substrate according to claim 2, wherein: The connecting bridge area includes a plurality of pixel units, and the orthographic projection of the signal line on the substrate is at least located within the pixel units in the connecting bridge area and the orthographic projection of the area between the pixel units in the connecting bridge area on the substrate.

4. The stretchable display substrate according to claim 1, wherein: The extending direction of the first hollow portion is substantially the same as the edge of the hole area.

5. The stretchable display substrate according to claim 1, wherein: The first hollow portion is not connected to the hole area.

6. The stretchable display substrate according to claim 5, wherein: A distance between a side wall of the first hollow portion close to the hole region and a side wall of the hole region close to the first hollow portion is greater than or equal to 2 μm.

7. The stretchable display substrate according to claim 5, wherein: Along the direction from the pixel island area to the hole area, the width of the first hollow portion is greater than or equal to 5um.

8. The stretchable display substrate according to claim 1, wherein: The first hollow portion and the hole area are communicated with each other.

9. The stretchable display substrate according to claim 8, wherein: An edge of the first hollow portion close to the hole area overlaps with an edge of the hole area close to the first hollow portion.

10. The stretchable display substrate according to any one of claims 5, 8 and 9, wherein: The pixel unit includes at least one sub-pixel, the sub-pixel includes a pixel circuit and a light-emitting device, the light-emitting device includes a stacked anode, an organic light-emitting layer, and a cathode; a partition structure is provided in the connection bridge area near the pixel unit, the organic light-emitting layer is disconnected at the partition structure, and the cathode is disconnected at the partition structure; A distance between a side wall of the first hollow portion close to the pixel unit and the partition structure is greater than or equal to 2 μm.

11. The stretchable display substrate according to any one of claims 5, 6 and 7, wherein: The first hollow portion is a closed structure arranged around the hole area.

12. The stretchable display substrate according to claim 11, wherein: The partition structure is a closed structure arranged around the first hollow portion.

13. The stretchable display substrate according to claim 1, wherein: A portion of the hole area includes: a first sub-hole area and a second sub-hole area extending along the first direction and arranged along the second direction, and a third sub-hole area extending along the second direction; another portion of the hole area includes: a fourth sub-hole area and a fifth sub-hole area extending along the second direction and arranged along the first direction, and a sixth sub-hole area extending along the first direction; the first direction and the second direction are approximately perpendicular, the third sub-hole area approximately connects the central areas of the first sub-hole area and the second sub-hole area, and the sixth sub-hole area approximately connects the central areas of the fourth sub-hole area and the fifth sub-hole area; The first hollow portion is at least arranged at at least one of the following positions: one side of the connection position between the first sub-hole area and the third sub-hole area, one side of the connection position between the second sub-hole area and the third sub-hole area, one side of the end of the first sub-hole area and one side of the end of the second sub-hole area, one side of the connection position between the fourth sub-hole area and the sixth sub-hole area, one side of the connection position between the fifth sub-hole area and the sixth sub-hole area, one side of the end of the fourth sub-hole area and one side of the end of the fifth sub-hole area.

14. The stretchable display substrate according to claim 13, wherein: The first hollow portion is provided on one side of the connection position between the first sub-hole area and the third sub-hole area, one side of the connection position between the second sub-hole area and the third sub-hole area, one side of the end of the first sub-hole area and one side of the end of the second sub-hole area, one side of the connection position between the fourth sub-hole area and the sixth sub-hole area, one side of the connection position between the fifth sub-hole area and the sixth sub-hole area, one side of the end of the fourth sub-hole area and one side of the end of the fifth sub-hole area.

15. The stretchable display substrate according to claim 1, wherein: The pixel island region includes at least one pixel unit, and the pixel resolution of the pixel island region is substantially the same as the pixel resolution of the connecting bridge region.

16. The stretchable display substrate according to claim 1, wherein: The multiple inorganic insulating layers include a first barrier layer, a buffer layer, a first gate insulating layer, a second gate insulating layer, an interlayer dielectric layer, a first passivation layer, a second passivation layer and an inorganic encapsulation layer stacked on the substrate, and the first hollow portion is set in at least one of the first barrier layer, the buffer layer, the first gate insulating layer, the second gate insulating layer, the interlayer dielectric layer, the first passivation layer, the second passivation layer and the inorganic encapsulation layer.

17. The stretchable display substrate according to claim 16, wherein: The interlayer dielectric layer, the first passivation layer, the second passivation layer, and the inorganic encapsulation layer are all provided with the first hollow portions, and the first hollow portions substantially overlap.

18. The stretchable display substrate according to claim 16, wherein: The inorganic encapsulation layer includes a first inorganic layer and a second inorganic layer stacked on the second passivation layer; The stretchable display substrate further includes: a first planarization layer and a second planarization layer located between the interlayer dielectric layer and the first passivation layer, a pixel definition layer located between the second passivation layer and the inorganic encapsulation layer, and an organic layer located between the first inorganic layer and the second inorganic layer; At least one of the first planar layer, the second planar layer, the pixel defining layer, and the organic layer has a second hollow portion near the hole region, and the first hollow portion and the second hollow portion substantially overlap.

19. The stretchable display substrate according to claim 16, wherein: The substrate includes a flexible layer, or the substrate includes a first flexible layer, a second barrier layer, and a second flexible layer stacked on a side of the first barrier layer facing away from the buffer layer.

20. A display device, wherein: Comprising a stretchable display substrate according to any one of claims 1-19.

21. A method for preparing a stretchable display substrate according to any one of claims 1 to 19, wherein: include: providing a substrate; forming pixel units and signal lines electrically connected to the pixel units on the substrate; A plurality of inorganic insulating layers are stacked on the substrate; wherein at least one of the plurality of inorganic insulating layers has a first hollow portion near the hole area, and the orthographic projection of the first hollow portion on the substrate does not overlap with the orthographic projection of the signal line and the pixel unit on the substrate.

22. The preparation method according to claim 21, wherein At least one of the plurality of inorganic insulating layers has a first hollow portion near the hole region, specifically comprising: Depositing a first barrier layer, a buffer layer, a first gate insulating layer, a second gate insulating layer, an interlayer dielectric layer, a first passivation layer, a second passivation layer and an inorganic encapsulation layer on the substrate; The first hollow portion is formed in at least one of the first barrier layer, the buffer layer, the first gate insulating layer, the second gate insulating layer, the interlayer dielectric layer, the first passivation layer, the second passivation layer and the inorganic encapsulation layer by using a patterning process.

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