阅读说明：本技术 一种基板及微发光二极管的转移方法 (Substrate and micro light emitting diode transfer method ) 是由 张骏 于 2021-09-08 设计创作，主要内容包括：本发明实施例公开了一种基板及微发光二极管的转移方法。其中基板包括：衬底；形变层,位于衬底上,形变层包括多个开口,开口的远离衬底一侧的尺寸小于开口的靠近所述衬底一侧的尺寸；形变层的弹性模量小于衬底的弹性模量。本发明实施例的技术方案,通过在形变层设置多个开口,开口的远离衬底一侧的尺寸小于开口的靠近衬底一侧的尺寸形变层的弹性模量小于衬底的弹性模量,且在形变层被拉伸时开口侧壁的斜率发生变化,使开口远离衬底一侧的尺寸张开至大于微发光二极管的尺寸,以使微发光二极管可以放入或取出；在形变层恢复时开口夹持微发光二极管,避免采用胶粘出现粘附力不一致的问题,有利于微发光二极管的批量转移。(The embodiment of the invention discloses a substrate and a transfer method of a micro light-emitting diode. Wherein the base plate includes: a substrate; the deformation layer is positioned on the substrate and comprises a plurality of openings, and the size of one side of each opening, which is far away from the substrate, is smaller than that of one side of each opening, which is close to the substrate; the modulus of elasticity of the deformable layer is less than the modulus of elasticity of the substrate. According to the technical scheme of the embodiment of the invention, the deformation layer is provided with the plurality of openings, the size of one side, far away from the substrate, of each opening is smaller than the elastic modulus of the size deformation layer, close to the substrate, of each opening, and the slope of the side wall of each opening is changed when the deformation layer is stretched, so that the size of one side, far away from the substrate, of each opening is expanded to be larger than the size of the micro light-emitting diode, and the micro light-emitting diode can be put in or taken out; when the deformation layer recovers, the opening clamps the micro light-emitting diode, the problem of inconsistent adhesion caused by gluing is avoided, and batch transfer of the micro light-emitting diode is facilitated.)

1. A substrate, comprising:

a substrate;

the deformation layer is positioned on the substrate and comprises a plurality of openings, and the size of one side of each opening, which is far away from the substrate, is smaller than that of one side of each opening, which is close to the substrate;

the elastic modulus of the deformation layer is less than the elastic modulus of the substrate.

2. The substrate of claim 1,

the substrate is a stretchable substrate.

3. The substrate of claim 1,

the cross section of the opening in a first section is trapezoidal, and the first section is perpendicular to the plane of the substrate.

4. The substrate of claim 1,

the opening is used for fixing the micro light-emitting diode;

the size of the side of the opening far away from the substrate is smaller than that of the micro light-emitting diode, and the size of the side of the opening close to the substrate is larger than or equal to that of the micro light-emitting diode.

5. The substrate of claim 1,

the deformation layer comprises a first deformation layer and a second deformation layer, the second deformation layer is positioned between the first deformation layer and the substrate, and the opening is at least arranged in the first deformation layer;

wherein the elastic modulus of the first deformation layer is less than the elastic modulus of the second deformation layer.

6. The substrate of claim 5,

the opening penetrates the first deformation layer in a thickness direction of the first deformation layer.

7. The substrate of claim 1, further comprising a detection electrode, wherein the opening exposes the detection electrode.

8. The substrate according to claim 7, wherein the detection electrode comprises a first detection electrode and a second detection electrode at the bottom of the opening;

when the micro light-emitting diode is fixed at the opening, the first detection electrode and the second detection electrode are respectively connected with the first electrode and the second electrode of the micro light-emitting diode.

9. The substrate according to claim 8, further comprising a plurality of first and second sensing electrode lines, the first sensing electrode line being electrically connected to the first sensing electrode, the second sensing electrode line being electrically connected to the second sensing electrode;

all the first detection electrode wires are connected to a first test end, and all the second detection electrode wires are connected to a second test end.

10. The substrate of claim 8, wherein the micro light emitting diodes comprise micro light emitting diodes with different light emitting colors, the first detecting electrode lines corresponding to the micro light emitting diodes with the same light emitting color are connected to the same testing terminal, and the second detecting electrode lines corresponding to the micro light emitting diodes with the same light emitting color are connected to the same testing terminal.

11. The substrate according to claim 9 or 10, wherein the first detection electrode lines and the second electrode lines are curved.

12. The substrate according to claim 7, wherein the detection electrode comprises a third detection electrode located at the bottom of the opening;

when the micro light-emitting diode is fixed at the opening, the third detection electrode is connected with the first electrode of the micro light-emitting diode.

13. The substrate of claim 7, wherein the substrate comprises a plurality of island structures, the detection electrode being located on the island structures.

14. A method for transferring a micro light emitting diode, wherein the micro light emitting diode disposed on an original substrate is transferred by using the substrate according to any one of claims 1 to 13, the method comprising:

stretching the deformation layer to a stretching state, so that the size of one side of the opening, which is far away from the substrate, is larger than that of the micro light-emitting diode, and the micro light-emitting diode is arranged opposite to the opening;

pressing the original substrate and the substrate to clamp the micro light-emitting diode into the opening;

and restoring the deformation layer to an unstretched state, and stripping the original substrate to separate the original substrate from the micro light-emitting diode.

15. The method of claim 14, wherein the substrate further comprises a detection electrode, and when the micro led is engaged into the opening, the detection electrode is connected to the electrode of the micro led; the transfer method of the micro light emitting diode further comprises the following steps:

and applying detection voltage to the detection electrode, and observing the light-emitting brightness of the micro light-emitting diode.

16. The method of claim 15, further comprising:

screening qualified micro light-emitting diodes in the process of applying detection voltage to the detection electrode for detection;

and transferring the qualified micro light-emitting diode.

17. The method of claim 14, wherein the substrate comprises a plurality of island structures, and the substrate changes the pitch of the two island structures under different tensile forces.

Technical Field

The embodiment of the invention relates to a display technology, in particular to a substrate and a micro light-emitting diode transfer method.

Background

A Micro light emitting diode (Micro LED) display is a display in which a high-density Micro-sized LED array is integrated on a substrate to realize image display; because of its advantages of high quality, thin body, low power consumption, etc., it is considered as the next generation display and gradually becomes the mainstream of the display device.

In the manufacturing process of the micro-light emitting diode display, a plurality of micro-light emitting diode arrays are generally grown on an original substrate (such as a sapphire substrate); then, the micro light emitting diode is peeled off from the original substrate by a laser peeling technique, and the micro light emitting diode is transferred to a predetermined position on a receiving substrate by using a transfer substrate and is bound with the receiving substrate.

In the batch transfer process of the micro light emitting diodes, a transfer substrate generally needs to transfer a plurality of micro light emitting diodes, however, the existing transfer substrate generally fixes the micro light emitting diodes by gluing, and if the gluing is too tight, the micro light emitting diodes are not easy to take down during the transfer and are easy to damage the diodes during the taking down; if the bond is too loose, the original substrate may carry away the micro-leds when removed, resulting in a lower transfer efficiency.

Disclosure of Invention

The embodiment of the invention provides a substrate and a micro light-emitting diode transfer method, wherein the substrate is provided with a deformation layer comprising a plurality of openings, and the slope of the side wall of each opening is changed when the deformation layer is stretched so as to clamp the micro light-emitting diodes, so that the micro light-emitting diodes can be transferred in batch.

In a first aspect, an embodiment of the present invention provides a substrate, including:

a substrate;

the deformation layer is positioned on the substrate and comprises a plurality of openings, and the size of one side of each opening, which is far away from the substrate, is smaller than that of one side of each opening, which is close to the substrate;

the elastic modulus of the deformation layer is less than the elastic modulus of the substrate.

In a second aspect, an embodiment of the present invention further provides a method for transferring a micro light emitting diode, where the micro light emitting diode disposed on an original substrate is transferred by using the substrate, and the method for transferring a micro light emitting diode includes:

stretching the deformation layer to a stretching state, so that the size of one side of the opening, which is far away from the substrate, is larger than that of the micro light-emitting diode, and the micro light-emitting diode is arranged opposite to the opening;

pressing the original substrate and the substrate to clamp the micro light-emitting diode into the opening;

and restoring the deformation layer to an unstretched state, and stripping the original substrate to separate the original substrate from the micro light-emitting diode.

The base plate provided by the embodiment of the invention comprises a substrate and a deformation layer positioned on the substrate, wherein a plurality of openings are arranged on the deformation layer, the elastic modulus of the deformation layer at one side of the opening, which is far away from the substrate, is smaller than that of the deformation layer at one side of the opening, which is close to the substrate, and is smaller than that of the substrate, and the slope of the side wall of the opening is changed when the deformation layer is stretched, so that the size of the opening, which is far away from the substrate, is expanded to be larger than that of a micro light-emitting diode, and the micro light-emitting diode can be put in or taken out; when the deformation layer recovers, the opening clamps the micro light-emitting diode, the problem of inconsistent adhesion caused by gluing is avoided, and batch transfer of the micro light-emitting diode is facilitated.

Drawings

FIG. 1 is a schematic diagram of a prior art substrate with micro-LEDs;

FIG. 2 is a schematic structural diagram of a transfer substrate of a micro LED in the related art;

fig. 3 is a schematic top view of a substrate according to an embodiment of the present invention;

FIG. 4 is a cross-sectional view taken along line A1A2 in FIG. 3;

FIG. 5 is a schematic view of the substrate of FIG. 4 in a stretched state;

FIGS. 6 and 7 are schematic views of alternative cross-sectional structures taken along section line A1A2 of FIG. 3;

FIG. 8 is a schematic cross-sectional view taken along line A1A2 in FIG. 3;

FIG. 9 is a schematic cross-sectional view taken along line A1A2 in FIG. 3;

fig. 10 is a schematic top view of another substrate according to an embodiment of the invention;

FIG. 11 is a cross-sectional view taken along line B1B2 in FIG. 10;

FIG. 12 is a cross-sectional view taken along line C1C2 of FIG. 10;

fig. 13 is a schematic top view illustrating a substrate according to another embodiment of the present invention;

fig. 14 is a schematic top view illustrating a substrate according to another embodiment of the present invention;

FIG. 15 is a cross-sectional view taken along line D1D2 in FIG. 14;

fig. 16 is a schematic flow chart illustrating a transfer method of a micro light emitting diode according to an embodiment of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.

The terminology used in the embodiments of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. It should be noted that the terms "upper", "lower", "left", "right", and the like used in the description of the embodiments of the present invention are used in the angle shown in the drawings, and should not be construed as limiting the embodiments of the present invention. In addition, in this context, it is also to be understood that when an element is referred to as being "on" or "under" another element, it can be directly formed on "or" under "the other element or be indirectly formed on" or "under" the other element through an intermediate element. The terms "first," "second," and the like, are used for descriptive purposes only and not for purposes of limitation, and do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

Micro light emitting diodes (Micro LEDs) are formed by thinning, miniaturizing, and arraying LED structures, and their sizes are only in the order of micrometers. The lower transfer efficiency of Micro LEDs has been limiting the development of Micro LED displays due to the reduction in size. Fig. 1 is a schematic structural diagram of an original substrate on which Micro light emitting diodes are formed in the related art, and referring to fig. 1, a plurality of Micro LEDs 2 are formed on the original substrate 1 by epitaxial growth, and a plurality of Micro LEDs 2 may form a Micro-LED array. Specifically, the Micro-LED2 may include a stacked substrate, an n-type layer, an active layer, and a p-type layer, the n-type layer and the p-type layer being respectively provided with an n-type electrode and a p-type electrode, and a specific structure of the Micro-LED is not shown in fig. 1. The original substrate 1 can be a sapphire substrate, a silicon carbide substrate or a gallium nitride substrate, so that the manufactured Micro LEDs 2 can be conveniently transferred to the receiving substrate, the Micro LEDs 2 can be divided or divided into a plurality of areas, and flexible transfer is facilitated.

Fig. 2 is a schematic structural diagram of a transfer substrate of a micro light emitting diode in the related art. Referring to fig. 2, the transfer substrate includes a substrate 3 and a bonding layer 4 located on one side of the substrate 3, where the substrate 3 is a hard substrate and can be made of a glass substrate, and the bonding layer 4 can be formed by disposing an acrylate bonding glue layer on the glass substrate; for example, polymethyl methacrylate resin is provided as a temporary bonding paste on the surface of the glass substrate. In the transfer of the Micro LEDs, the substrate 3 and the original base board 1 are disposed to face each other, and the adhesive layer 4 is located on the side facing the original base board 1 to bond the Micro LEDs 2. When the Micro LED2 is transferred, the original substrate 1 and the Micro LED2 are separated by adopting a laser removing mode, and the adhesive force of the adhesive layer 4 to the Micro LED2 is uncontrollable, so that the adhesive force is difficult to remove from the transfer substrate during the transfer if the adhesive force is too large; if the adhesion is too low, the Micro LEDs may be taken away when the original substrate is removed, affecting the transfer efficiency.

In view of this, an embodiment of the present invention provides a substrate for transferring Micro LEDs, so as to improve the transfer yield. Fig. 3 is a schematic top view of a substrate according to an embodiment of the invention, and fig. 4 is a schematic cross-sectional view taken along a sectional line A1a2 in fig. 3. Referring to fig. 3 and 4, the present embodiment provides a substrate including a substrate 10; the deformation layer 20 is positioned on the substrate 10, the deformation layer 20 comprises a plurality of openings 201, and the size of the side, far away from the substrate 10, of each opening 201 is smaller than that of the side, close to the substrate 10, of each opening 201; the modulus of elasticity of the deformable layer 20 is less than the modulus of elasticity of the substrate 10.

In this embodiment, the substrate 10 is a stretchable substrate, the stretchable substrate is formed by a flexible material, has a certain elasticity, can be stretched and deformed when receiving a tensile force, and can be restored to an original shape after the tensile force is removed, in a specific implementation, the substrate 10 may be formed by a flexible organic material, for example, a material such as polyimide PI, polydimethylsiloxane PDMS, and the like, and may be selected according to an actual situation in the specific implementation. The deformation layer 20 is located on one side of the substrate 10, and may also be formed by a flexible organic material, and the elastic modulus of the deformation layer 20 is smaller than that of the substrate 10, so that the deformation of the deformation layer 20 is larger when the substrate is subjected to the same tensile force, which is beneficial to the opening of the opening 201. The deformation layer 20 may be formed by using photoresist PR, PI, PDMS, or the like, and specifically, when the same material is used for the deformation layer and the substrate, the elastic modulus may be adjusted by controlling different processes or doping materials with different concentrations.

In fig. 3, for example, the top profile of the opening 201 is rectangular, and referring to fig. 4, the cross-sectional shape of the opening 201 in a first cross-section perpendicular to the plane of the substrate is trapezoidal, and the width d1 of the side (top) of the opening 201 away from the substrate 10 is smaller than the width d2 of the side (bottom) of the opening close to the substrate 10. Also schematically shown in FIG. 4 is a Micro LED30 corresponding to opening 201, where the size of the Micro LED30 is on the order of microns, which may be between 100 μm and 10 μm, or 20 μm and 30 μm, for example. The opening 201 is used to hold the Micro LED 30. It can be understood that fig. 4 is a schematic structural diagram of the base plate in an unstretched state, in which the width d1 of the side of the opening 201 away from the substrate 10 is smaller than the width d3 of the Micro LED30, and the width d2 of the side of the opening 201 close to the substrate 10 is greater than or equal to the width d3 of the Micro LED30, that is, d1< d3 ≦ d2, so that the Micro LED30 can be put in when the opening 20 is stretched, and the Micro LED30 can be fixed when the opening is recovered.

Exemplarily, fig. 5 is a schematic structural diagram of the substrate in fig. 4 in a stretched state, when the substrate is in the stretched state, the inclination rate of the sidewall of the opening 201 changes, so that d3< d1< d2, thereby placing the Micro LED30 in the opening 201.

It should be noted that the cross-sectional shape of the opening 201 shown in fig. 4 is only an exemplary shape, in other embodiments, the cross-section of the opening 201 may be other shapes, for example, fig. 6 and fig. 7 are schematic cross-sectional structures along a sectional line A1a2 in fig. 3, respectively, and referring to fig. 6 and fig. 7, the shape of the opening 201 may be an arc, which may be selected according to practical situations in particular implementations as long as the size of the top end of the opening 201 is smaller than that of the bottom end, and the Micro LED may be fixed.

The base plate provided by the embodiment of the invention comprises a substrate and a deformation layer positioned on the substrate, wherein a plurality of openings are arranged on the deformation layer, the elastic modulus of the deformation layer at one side of the opening, which is far away from the substrate, is smaller than that of the deformation layer at one side of the opening, which is close to the substrate, and is smaller than that of the substrate, and the slope of the side wall of the opening is changed when the deformation layer is stretched, so that the size of the opening, which is far away from the substrate, is expanded to be larger than that of a micro light-emitting diode, and the micro light-emitting diode can be put in or taken out; when the deformation layer recovers, the opening clamps the micro light-emitting diode, the problem of inconsistent adhesion caused by gluing is avoided, and batch transfer of the micro light-emitting diode is facilitated.

On the basis of the above embodiment, optionally, the deformation layer includes a first deformation layer and a second deformation layer, the second deformation layer is located between the first deformation layer and the substrate, and the opening is at least arranged in the first deformation layer; wherein the elastic modulus of the first deformation layer is less than the elastic modulus of the second deformation layer.

Illustratively, fig. 8 is a schematic view of another cross-sectional structure taken along the cross-sectional line A1a2 in fig. 3. Referring to fig. 8, the deformable layer 20 includes a second deformable layer 22 and a first deformable layer 21 stacked on one side of the substrate 10, in this embodiment, the opening 201 is disposed in a partial region of the first deformable layer 21 and the second deformable layer 22, and by setting the elastic modulus of the first deformable layer 21 to be smaller than that of the second deformable layer 22, that is, the elastic modulus of the film layer from top to bottom is gradually increased, so that the upper part is easily opened and the lower part is not easily opened when the substrate is stretched, which is beneficial for fixing the Micro LED. With continued reference to fig. 8, an opening 201 extends through the first deformable layer 21 in the thickness direction of the first deformable layer 21. In other embodiments, the opening may not penetrate through the first deformation layer, or may penetrate through both the first deformation layer and the second deformation layer, and the implementation may be designed according to actual situations.

In another embodiment, the first deformation layer may further include a plurality of sub-film layers stacked one on another, for example, fig. 9 is a schematic view of a cross-sectional structure taken along a sectional line A1a2 in fig. 3, in this embodiment, the first deformation layer 21 includes a first sub-deformation layer 211, a second sub-deformation layer 212 and a third sub-deformation layer 213, wherein elastic moduli of the first sub-deformation layer 211, the second sub-deformation layer 212 and the third sub-deformation layer 213 are sequentially increased, thereby facilitating fixing the Micro LED.

In the process of manufacturing Micro LEDs, defects such as some Micro LEDs cannot emit light or brightness is insufficient due to process defects and the like, or devices may be damaged due to device breakage and the like when the Micro LEDs are peeled from an original substrate. In order to avoid defective Micro LEDs being transferred into the display, it is also generally necessary that the substrate used to transfer the Micro LEDs has a detection function. In another embodiment of the present invention, optionally, the substrate provided in the embodiment of the present invention further includes a detection electrode, and the opening exposes the detection electrode. Through set up detection electrode on the base plate, when Micro LED was transferred to the base plate on, detection electrode and Micro LED's electrode connection to realize Micro LED's luminance detection, select qualified Micro LED.

Exemplarily, fig. 10 is a schematic top view of another substrate according to an embodiment of the present invention, fig. 11 is a schematic cross-sectional structure along a cross-sectional line B1B2 in fig. 10, referring to fig. 10 and fig. 11, optionally, the substrate further includes a detection electrode 40, and the detection electrode 40 includes a first detection electrode 41 and a second detection electrode 42 located at the bottom of the opening 201; when the Micro LED30 is fixed to the opening 201, the first detection electrode 41 and the second detection electrode 42 are connected to the first electrode 31 and the second electrode 32 of the Micro LED30, respectively.

The first electrode 31 may be a p-electrode, the second electrode 32 may be an n-electrode, or the first electrode 31 may be an n-electrode, and the second electrode 32 may be a p-electrode, which may be designed according to practical situations in specific implementation. When the Micro LED30 is fixed in the opening 201, the first detection electrode 41 and the first electrode 31 are correspondingly electrically connected in a contact manner, and the second detection electrode 42 and the second electrode 32 are correspondingly electrically connected, so that the brightness detection of the Micro LED30 can be realized when electricity is supplied.

Fig. 12 is a schematic cross-sectional view taken along a sectional line C1C2 in fig. 10, and referring to fig. 10 and 12, the substrate further includes a plurality of first sensing electrode lines 51 and second sensing electrode lines 52, the first sensing electrode lines 51 are electrically connected to the first sensing electrodes 41, and the second sensing electrode lines 52 are electrically connected to the second sensing electrodes 42; all the first sensing electrode lines 51 are connected to the first test terminal 61, and all the second sensing electrode lines 52 are connected to the second test terminal 62.

Illustratively, taking the first electrode 31 as a p-electrode and the second electrode 32 as an n-electrode as an example, the first test terminal 61 provides a positive voltage, which is transmitted to the first detection electrode 41 through the first detection electrode line 51, and the second test terminal 62 provides a negative voltage, which connects the Micro LED30 into the loop to realize brightness detection.

It should be noted that the top view of the substrate shown in fig. 10 is only schematic, all the first detecting electrode lines 51 in fig. 10 are connected to one first testing terminal 61, and all the second detecting electrode lines 52 are connected to one second testing terminal 62, in other embodiments, in order to reduce the influence of voltage drop caused by the resistances of the detecting electrode lines, a plurality of testing terminals may be provided. In addition, in other embodiments, in order to ensure the tensile property of the substrate and avoid the problems of breakage and the like of the detection electrode lines during stretching, optionally, the first detection electrode line and the second detection electrode line are in curved shapes. The specific curve shape is not limited in the embodiment of the present invention, and may be, for example, a zigzag shape, a wavy shape, or the like, and may be designed according to actual situations in specific implementation.

In the substrate provided with the detection electrode, the position of the detection electrode is fixed and does not change with the stretching of the substrate, so that the detection electrode can be provided on an island-like structure which hardly deforms. Illustratively, with continued reference to fig. 12, the substrate includes a plurality of island structures 70, with the first and second detection electrodes 41, 42 each being located on the island structures 70.

Exemplarily, fig. 12 also shows a specific film diagram of an island-shaped structure 70, which includes a first inorganic layer 71, a first conductive layer 72, a second inorganic layer 73, and a second conductive layer 74, which are stacked, wherein the first conductive layer 72 forms the first detection electrode line 51 or the second detection electrode line 52, the second conductive layer 74 forms the first detection electrode 41 (shown in fig. 12 as a cross section of the first detection electrode line 51 and the first detection electrode 41), and the second conductive layer 74 is connected to the first inorganic layer 71 through a via hole disposed on the second inorganic layer 73, wherein the inorganic layer may be silicon oxide, silicon nitride, or the like, and the inorganic layer has a large elastic modulus, and may not deform or deform less when the substrate is stretched.

Optionally, the micro light emitting diodes include micro light emitting diodes of a plurality of different light emitting colors, first detection electrode lines corresponding to the micro light emitting diodes of the same light emitting color are connected to the same testing end, and second detection electrode lines corresponding to the micro light emitting diodes of the same light emitting color are connected to the same testing end.

When the display panel realizes color display, Micro LEDs with different light emitting colors, such as red Micro LEDs, green Micro LEDs and blue Micro LEDs, are generally required, and for the Micro LEDs with different light emitting colors, the test voltages are different, so that corresponding test electrodes can be arranged according to the Micro LEDs with different colors. Exemplarily, fig. 13 is a schematic top view of a substrate according to another embodiment of the present invention. Referring to fig. 13, the Micro LEDs include red Micro LEDs, green Micro LEDs and blue Micro LEDs, detection electrode lines 51R corresponding to the red Micro LEDs are connected to a test terminal 61R, detection electrode lines 52R corresponding to the red Micro LEDs are connected to a test terminal 62R, detection electrode lines 51G corresponding to the green Micro LEDs are connected to a test terminal 61G, detection electrode lines 52G corresponding to the green Micro LEDs are connected to a test terminal 62G, detection electrode lines 51B corresponding to the blue Micro LEDs are connected to a test terminal 61B, detection electrode lines 52B corresponding to the blue Micro LEDs are connected to a test terminal 62B, and test requirements of the Micro LEDs with different light emitting colors are met.

In the above embodiments, the two electrodes of the Micro LED are located on the same side, in another embodiment, the two electrodes of the Micro LED may be disposed on different sides, for example, the p electrode is disposed on a side away from the original substrate and connected to the detection electrode of the substrate during testing, and the n electrode is disposed on a side close to the original substrate and electrically connected together, for example, fig. 14 is a schematic top view structure diagram of another substrate provided by an embodiment of the present invention, fig. 15 is a schematic cross-sectional structure diagram along a section line D1D2 in fig. 14, referring to fig. 14 and fig. 15, in this embodiment, the detection electrode 40 includes a third detection electrode 43 located at the bottom of the opening 201; when the Micro LED30 is fixed to the opening 201, the third detection electrode 43 is connected to the first electrode 31 of the Micro LED 30. During testing, the Micro LED30 can be tested by using an original substrate or by designing a cover plate which can be connected with a second electrode.

Fig. 16 is a schematic flow chart of a transfer method for micro light emitting diodes according to an embodiment of the present invention, where the transfer method provided in this embodiment transfers micro light emitting diodes disposed on an original substrate by using any one of the substrates provided in the above embodiments, and referring to fig. 16, the transfer method for micro light emitting diodes provided in this embodiment includes:

and S110, stretching the deformation layer to a stretching state, so that the size of one side of the opening, which is far away from the substrate, is larger than that of the micro light-emitting diode, and the micro light-emitting diode is arranged opposite to the opening.

Wherein, under the default state, the size of opening top is less than little emitting diode's size, and the size of opening bottom is greater than or equal to little emitting diode's size, and when tensile, the size of opening top and bottom all is greater than little emitting diode's size to do benefit to little emitting diode of centre gripping.

And step S120, pressing the original substrate and the substrate together to clamp the micro light-emitting diode into the opening.

And S130, restoring the deformation layer to an unstretched state, and stripping the original substrate to separate the original substrate from the micro light-emitting diode.

Wherein, the original substrate and the micro light emitting diode can be stripped by adopting a laser stripping technology.

According to the technical scheme of the embodiment of the invention, the deformation layer is stretched to a stretching state, and the slope of the side wall of the opening is changed when the deformation layer is stretched, so that the size of the side, away from the substrate, of the opening is expanded to be larger than that of the micro light-emitting diode, and the micro light-emitting diode can be put in or taken out; when the deformation layer recovers, the opening clamps the micro light-emitting diode, the problem of inconsistent adhesion caused by gluing is avoided, and batch transfer of the micro light-emitting diode is facilitated.

Optionally, in another embodiment, the substrate further includes a detection electrode, and when the micro light emitting diode is clamped into the opening, the electrode of the micro light emitting diode is connected to the detection electrode; the transfer method of the micro light emitting diode further comprises the following steps:

and applying detection voltage to the detection electrode, and observing the light-emitting brightness of the micro light-emitting diode.

By arranging the detection electrode, the brightness detection of the micro light-emitting diode can be realized, and unqualified micro light-emitting diodes can be removed. Further, the transfer method provided by this embodiment further includes:

screening qualified micro light-emitting diodes in the process of applying detection voltage to the detection electrode for detection;

and transferring qualified micro light-emitting diodes. And defects of the prepared display panel are avoided.

Optionally, the substrate includes a plurality of island-shaped structures, and the substrate changes the distance between two island-shaped structures under the action of different tensile forces. Therefore, the micro light-emitting diodes with different pitches can be transferred in a matching manner, and the universality of the substrate is improved.

It is to be noted that the foregoing is only illustrative of the preferred embodiments of the present invention and the technical principles employed. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious modifications, rearrangements, combinations and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail by the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present invention, and the scope of the present invention is determined by the scope of the appended claims.