Seal and preparation method thereof, transfer equipment and mass transfer method

Abstract

The seal comprises a base plate and a plurality of anti-inclination structures which are located on one side of the base plate and distributed at intervals. The multiple transfer structures are located on the side, where the anti-inclination structures are located, of the base plate and distributed at intervals; at least one hole is formed in the transfer structure and at least provided with a first opening located in the first surface of the side, away from the substrate, of the transfer structure; the plurality of anti-inclination structures are in one-to-one correspondence with the plurality of transfer structures, the anti-inclination structures surround the peripheries of the transfer structures, and orthographic projections of the anti-inclination structures and the transfer structures on the substrate are not overlapped; the distance between the end face of the end, away from the substrate, of the anti-inclination structure and the substrate is larger than or equal to the distance between the end face of the end, away from the substrate, of the transfer structure and the substrate.

Description

Seal and its preparation method, transfer equipment and mass transfer method Technical Field

[0001] The embodiments of the present disclosure belong to the field of display technology, and specifically relate to a seal and a preparation method thereof, a transfer device, and a mass transfer method. Background Art

[0002] Micro LED (Micro Light-Emitting Diode) has the characteristics of self-luminescence without the need for a backlight. Compared with LCD (Liquid Crystal Display) and OLED (Organic Light Emitting Display) products, it has the advantages of simple structure, very long service life, high brightness, low power consumption, ultra-high resolution, etc., and has good application prospects.

[0003] Summary of the Invention

[0004] In a first aspect, an embodiment of the present disclosure provides a seal, which includes a substrate,

[0005] A plurality of anti-tilt structures are located on one side of the base plate and are distributed at intervals;

[0006] A plurality of transfer structures are located on one side of the substrate where the anti-tilt structure is located and are distributed at intervals;

[0007] At least one hole is formed in the transfer structure, and the hole has at least a first opening located on a first surface of the transfer structure facing away from the substrate;

[0008] The multiple anti-tilt structures correspond one-to-one to the multiple transfer structures.

[0009] The anti-tilt structure surrounds the periphery of the transfer structure, and the anti-tilt structure and the orthographic projection of the transfer structure on the substrate do not overlap;

[0010] The distance between the end surface of the anti-tilt structure away from the substrate and the substrate is greater than or equal to the distance between the end surface of the transfer structure away from the substrate and the substrate.

[0011] In some embodiments, the holes extend through the thickness of the transfer structure.

[0012] In some embodiments, the hole is a blind hole opened in the transfer structure.

[0013] In some embodiments, the light emitting diode has a second surface in contact with the first surface of the transfer structure, and an orthographic projection of the second surface on the substrate falls within the orthographic projection range of the first surface on the substrate;

[0014] The number of the hole is one;

[0015] The size of any side edge of the first surface is larger than the size of the corresponding side edge of the second surface and larger than the size of the corresponding side edge of the first opening;

[0016] 1 / 2 of the difference between the size of any side edge of the first surface and the size of the corresponding side edge of the first opening is greater than the alignment accuracy of an alignment device for aligning and bonding the light emitting diode and the transfer structure.

[0017] In some embodiments, the first surface of the transfer structure includes a middle region and a peripheral region, the peripheral region surrounding the middle region;

[0018] There are multiple holes, and the first openings of the multiple holes are evenly distributed in the middle area.

[0019] In some embodiments, the light emitting diode has a second surface in contact with the first surface of the transfer structure, and an orthographic projection of the second surface on the substrate falls within the orthographic projection range of the first surface on the substrate;

[0020] The size of any side edge of the first surface is larger than the size of the corresponding side edge of the second surface, and larger than the size of the corresponding side edge of the middle area;

[0021] 1 / 2 of the difference between the size of any side edge of the first surface and the size of the corresponding side edge of the middle area is greater than the alignment accuracy of an alignment device for aligning and bonding the light emitting diode and the transfer structure.

[0022] In some embodiments, the first surface of the transfer structure is used to contact and fit with the second surface of the light-emitting diode, and the distance between the end surface of the anti-tilt structure away from the substrate and the substrate is smaller than the distance between the end surface of the light-emitting diode away from the substrate and the substrate.

[0023] In some embodiments, the anti-tilt structure has an orthographic projection shape on the substrate that is annular.

[0024] The transfer structure and the anti-tilt structure are butted against each other in orthographic projection patterns on the substrate.

[0025] In some embodiments, the orthographic projection shape of the transfer structure on the substrate includes a circle, a rectangle, a triangle, or a polygon.

[0026] In some embodiments, the orthographic projection shape of the first opening on the substrate includes a circle, a rectangle, a triangle, or a polygon.

[0027] In some embodiments, a cross-sectional shape of the hole perpendicular to the substrate includes a rectangle, a trapezoid, or an inverted trapezoid.

[0028] In some embodiments, the plurality of transfer structures are arranged in an array at equal intervals;

[0029] The orthographic projection shapes of the plurality of transfer structures on the substrate are the same, and the directions of the orthographic projection patterns of any two adjacent columns of the transfer structures on the substrate are different;

[0030] Alternatively, the orthographic projection shape of a portion of the plurality of transfer structures on the substrate is different from the orthographic projection shape of another portion on the substrate.

[0031] In some embodiments, a portion of the plurality of transfer structures are arranged in an array at a first interval, and another portion are arranged in an array at a second interval, wherein the first interval is greater than the second interval.

[0032] In some embodiments, the transfer structure is made of elastic resin material.

[0033] The elastic resin material includes any one of acrylic resin, propylene glycol methyl ether acetate, silicone resin and acrylic resin.

[0034] In some embodiments, the anti-tilt structure is made of any one of silicon oxide, silicon nitride, silicon oxynitride, copper, aluminum, molybdenum, and silver.

[0035] In some embodiments, the height of the transferred structure ranges from 4 μm to 15 μm.

[0036] In some embodiments, the width of the annular surface of the anti-tilt structure ranges from 2 to 30 μm.

[0037] In a second aspect, an embodiment of the present disclosure further provides a transfer device, which includes the above-mentioned seal.

[0038] In a third aspect, an embodiment of the present disclosure further provides a method for preparing a seal, which includes: preparing a plurality of anti-tilt structures on one side of a substrate using a patterning process;

[0039] A plurality of transfer structures are prepared on one side of the substrate after completing the above steps by using a patterning process; the plurality of transfer structures and the plurality of anti-tilt structures are located on the same side of the substrate;

[0040] The preparing of the plurality of transfer structures includes simultaneously forming the pattern of the transfer structures and the pattern of the holes in the transfer structures.

[0041] In some embodiments, the method of preparing a plurality of anti-tilt structures on one side of the substrate using a patterning process includes:

[0042] Depositing an anti-tilt structure film on one side of the substrate;

[0043] coating a photoresist layer on a side of the anti-tilt structure film facing away from the substrate;

[0044] exposing the photoresist layer using a mask including the anti-tilt structure pattern;

[0045] Developing and removing the photoresist in the exposed area of ​​the photoresist layer;

[0046] Etching away the anti-tilt structure film not covered by the photoresist by dry etching or wet etching to form patterns of the plurality of anti-tilt structures;

[0047] The remaining photoresist is stripped off.

[0048] In some embodiments, the step of preparing a plurality of transfer structures on one side of the substrate after completing the above steps by using a patterning process includes:

[0049] Applying an organic resin material layer on one side of the substrate;

[0050] exposing the organic resin material layer using a mask including the transfer structure pattern;

[0051] The organic resin material in the exposed area of ​​the organic resin material layer is removed by development to form patterns of the plurality of transfer structures.

[0052] In a fourth aspect, embodiments of the present disclosure provide a mass transfer method, comprising: aligning a stamp with a transfer substrate carrying a plurality of light-emitting diodes in a process chamber in a first vacuum environment, and then returning the process chamber to an atmospheric environment to enable the stamp to pick up the light-emitting diodes;

[0053] The air pressure in the first vacuum environment is lower than the air pressure in the atmospheric environment; the multiple transfer structures in the stamp correspond one-to-one to at least some of the light-emitting diodes, and the second surfaces of the light-emitting diodes cover the first openings on the first surfaces of the transfer structures, so that the holes in the transfer structures form closed cavities;

[0054] In a process chamber in an atmospheric environment, the stamp transfers the picked-up light-emitting diode to a driving substrate, and completes bonding between the first connection end of the light-emitting diode and the second connection end on the driving substrate. The process chamber is then evacuated to a second vacuum environment to release the light-emitting diode from the stamp.

[0055] The air pressure in the second vacuum environment is lower than the air pressure in the first vacuum environment.

[0056] In some embodiments, aligning the stamp with the transfer substrate carrying a plurality of light-emitting diodes in a process chamber in a first vacuum environment, and then returning the process chamber to an atmospheric environment to enable the stamp to pick up the light-emitting diodes, includes:

[0057] Aligning and pressing the stamp and the transfer substrate in a process chamber with a first vacuum environment;

[0058] Restoring the process chamber to an atmospheric environment to form a negative pressure in the closed cavity;

[0059] Dissociating the adhesive layer on the transfer substrate for fixing the light-emitting diode by laser dissociation;

[0060] The dissociated transfer substrate is separated from the stamp, and the light-emitting diode is transferred to the stamp.

[0061] In some embodiments, the stamp transfers the picked-up light-emitting diode to a driving substrate in a process chamber in an atmospheric environment, and bonds the first connection end of the light-emitting diode to the second connection end on the driving substrate. The process chamber is then evacuated to a second vacuum environment to release the light-emitting diode from the stamp, which includes:

[0062] Aligning and laminating the stamp carrying the light-emitting diode and the driving substrate in a process chamber in an atmospheric environment, so that the first connecting end of the light-emitting diode is aligned with the second connecting end on the driving substrate;

[0063] Applying pressure to the stamp side and heating the drive substrate side to complete the bonding between the first connecting end and the second connecting end;

[0064] evacuating the process chamber to the second vacuum environment to form a positive pressure in the closed cavity;

[0065] The stamp is separated from the light emitting diode, and the light emitting diode is transferred to the driving substrate.

[0066] In some embodiments, applying pressure to the stamp side comprises:

[0067] Mechanical compression;

[0068] Alternatively, the gas is pressurized. BRIEF DESCRIPTION OF THE DRAWINGS

[0069] The accompanying drawings are used to provide a further understanding of the embodiments of the present disclosure and constitute a part of the specification. Together with the embodiments of the present disclosure, they are used to explain the present disclosure and do not constitute a limitation of the present disclosure. The above and other features and advantages will become more apparent to those skilled in the art by describing the detailed exemplary embodiments with reference to the accompanying drawings, in which:

[0070] Figure 1a is a schematic diagram of the van der Waals force seal transfer process and principle.

[0071] Figure 1b shows the relationship between the energy release rate and the peeling rate during the van der Waals stamp pickup and release process.

[0072] Figure 1c is a schematic cross-sectional view of the structure of the PDMS stamp.

[0073] Figure 1d is a schematic diagram of the application of PDMS stamps in large-scale, multiple, and massive transfers.

[0074] Figure 1e is a schematic diagram of the application of PDMS stamp in small-size array transfer.

[0075] FIG2 a is a schematic top view of the structure of a seal in an embodiment of the present disclosure.

[0076] FIG2 b is a schematic cross-sectional view of the seal structure along the AA′ section line in FIG2 a .

[0077] FIG. 2 c is a schematic cross-sectional view of another structure of the seal along the AA′ section line in FIG. 2 a .

[0078] FIG2 d is a top view schematically showing a dimensional relationship between the first surface of the transfer structure, the first opening, and the second surface of the light-emitting diode in the seal according to an embodiment of the present disclosure.

[0079] FIG2 e is a cross-sectional schematic diagram showing a dimensional relationship between the first surface of the transfer structure, the first opening, and the second surface of the light-emitting diode in the seal according to an embodiment of the present disclosure.

[0080] FIG2 f is a top view schematically showing another dimensional relationship between the first surface of the transfer structure, the first opening, and the second surface of the light-emitting diode in the stamp according to an embodiment of the present disclosure.

[0081] FIG2g is a schematic cross-sectional view of the structure of the transfer structure in the seal according to the embodiment of the present disclosure that adsorbs the light-emitting diode.

[0082] FIG2h is a schematic top view of the structure of another seal in an embodiment of the present disclosure.

[0083] FIG2i is a schematic top view of the structure of another seal in an embodiment of the present disclosure.

[0084] FIG2j is a schematic cross-sectional view of another structure of the seal along the AA′ section line in FIG2a.

[0085] FIG. 2k is a schematic cross-sectional view of another structure of the seal along the AA′ section line in FIG. 2a .

[0086] FIG21 is a schematic top view of the structure of another seal in an embodiment of the present disclosure.

[0087] FIG2m is a schematic top view of the structure of another seal in an embodiment of the present disclosure.

[0088] FIG2n is a schematic top view of the structure of another seal in an embodiment of the present disclosure.

[0089] FIG3 is a flow chart of a process for preparing a seal according to an embodiment of the present disclosure.

[0090] FIG4 a is a flow chart of a mass transfer method according to an embodiment of the present disclosure.

[0091] FIG4 b is a schematic diagram of a process in which a stamp picks up a light-emitting diode from a transfer substrate in an embodiment of the present disclosure.

[0092] FIG4 c is a schematic diagram showing a process in which a stamp transfers a light-emitting diode to a driving substrate and releases the stamp in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0093] In order to enable those skilled in the art to better understand the technical solutions of the embodiments of the present disclosure, a seal, a preparation method thereof, a transfer device and a mass transfer method provided by the embodiments of the present disclosure are further described in detail below in conjunction with the drawings and specific implementation methods.

[0094] The embodiments of the present disclosure will be described more fully below with reference to the accompanying drawings, but the illustrated embodiments may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete and will fully enable those skilled in the art to understand the scope of this disclosure.

[0095] The embodiments of the present disclosure are not limited to the embodiments shown in the drawings, but include modifications of the configurations formed based on the manufacturing process. Therefore, the regions illustrated in the drawings are schematic in nature, and the shapes of the regions shown in the drawings illustrate specific shapes of the regions, but are not intended to be limiting.

[0096] Micro-LED mass production still faces numerous challenges, with the most prominent technical bottlenecks being mass transfer and bonding. Micro-LED mass transfer involves electrostatic adsorption transfer, stamp transfer, and magnetic adsorption transfer. Currently, the most widely used transfer method is van der Waals stamp (PDMS) transfer, and the most widely used bonding method is eutectic bonding.

[0097] The van der Waals stamp transfer principle and process flow are shown in the figure below. The PDMS stamp itself has a certain degree of stickiness, and the degree of adhesion to the Micro-LED is adjusted by the lifting speed. Rapid lifting results in strong adhesion to the Micro-LED interface, enabling Micro-LED pickup. Slow lifting results in weak adhesion (adhesion less than the bonding force between the Micro-LED connector and the driver substrate connector), enabling Micro-LED placement and release.

[0098] Referring to Figure 1a, it is a schematic diagram of the van der Waals force stamp transfer process and principle; Figure 1b is a diagram showing the relationship between the energy release rate and the peeling rate during the van der Waals force stamp pickup and release process; the elastic PDMS stamp 9 is aligned with the Micro-LED device 10 on the transfer substrate 7 and quickly pressed down; the PDMS stamp 9 deforms and fits tightly with the Micro-LED device 10; the PDMS stamp 9 is quickly lifted up to pull up the Micro-LED device 10; the PDMS stamp 9 carries the Micro-LED device 10 and is aligned with the driving substrate 8 and quickly pressed down; the PDMS stamp 9 slightly deviates to one side and is slowly lifted up; the PDMS stamp 9 recovers its deformation and separates from the Micro-LED device 10, completing the transfer of the Micro-LED device 10.

[0099] Referring to Figure 1c, a schematic cross-sectional view of the PDMS stamp structure is shown. The PDMS stamp 9 comprises a glass substrate 91 and a stamp structure 92 disposed on the glass substrate 91. The stamp structure 92 includes a base material 921 and a protrusion 922 integrally formed with the base material 921 and located on one side of the base material 921. Larger driver substrate sizes are a future product trend. Currently, PDMS stamps are suitable for transferring driver substrates up to 4 inches. As the PDMS stamp size increases, the height (i.e., thickness) uniformity of the stamp structure 92 itself decreases, reducing the transfer bonding yield.

[0100] Referring to Figure 1d, there is a schematic diagram of the application of the PDMS stamp in large-scale multiple mass transfers; Figure 1e is a schematic diagram of the application of the PDMS stamp in small-scale array transfers; as shown in Figure 1d, the PDMS stamp transfers the Micro-LED devices on the transfer substrate to the large-scale driving substrate through multiple mass transfers; as shown in Figure 1e, the PDMS stamp transfers the Micro-LED devices arranged in an array in small-scale local areas on the transfer substrate to the small-scale driving substrate.

[0101] At present, the PDMS stamp mass transfer technology is more suitable for the transfer of Micro-LED device arrays on small-sized driving substrates 8. There are the following problems in the mass transfer application of Micro-LED devices on large-sized driving substrates 8: For the mass transfer application of Micro-LED devices on larger-sized driving substrates 8, the increase in the area of ​​the driving substrate 8 means that more Micro-LED devices are required to participate in the transfer bonding process. The transfer rate, transfer yield and cost of Micro-LED devices are the key.

[0102] On the one hand, the stamp structure of the PDMS stamp 9 is prepared by injection molding using special materials (i.e., materials that can achieve fast pickup and slow release of Micro-LED devices). The preparation process is complex and the cost is high, and it is not suitable for mass production and large-scale transfer of large-size driving substrates 8.

[0103] On the other hand, the mass bonding method between the Micro-LED device and the driving substrate 8 is metal eutectic bonding, which needs to be carried out under high temperature and high pressure, such as the temperature is usually 180-300°C; ① During the bonding process, the high temperature and high pressure environment will cause the stamp structure of the PDMS stamp 9 to expand and deform, thereby reducing the transfer accuracy of the Micro-LED device, and the larger the stamp structure size of the PDMS stamp 9, the more obvious this adverse effect, therefore limiting the PDMS stamp 9 to be prepared into a small size, and the small-sized PDMS stamp 9 greatly reduces the transfer efficiency of the mass transfer of the large-sized driving substrate 8; ② Since the PDMS stamp 9 can only be prepared into a small size, multiple transfer bondings are required for the mass transfer of the large-sized driving substrate 8, and the repeated high temperature environment will cause the PDMS stamp 9 to age, resulting in its adhesion gradually weakening, resulting in unstable yield after multiple transfers.

[0104] In order to solve the problems of high cost, low transfer efficiency and unstable transfer yield in the current use of PDMS stamps to achieve mass transfer, on the first hand, an embodiment of the present disclosure provides a stamp, referring to Figures 2a and 2b, Figure 2a is a schematic top view of the structure of a stamp in the embodiment of the present disclosure; Figure 2b is a schematic cross-sectional view of the structure of the stamp along the AA' section line in Figure 2a; wherein the stamp includes a substrate 1, a plurality of anti-tilt structures 2, which are located on one side of the substrate 1 and are distributed at intervals; a plurality of transfer structures 3, which are located on the side of the substrate 1 where the anti-tilt structures 2 are located and are distributed at intervals; at least one hole 30 is opened in the transfer structure 3, and the hole 30 has at least a first opening 300 located on a first surface 31 on the side of the transfer structure 3 away from the substrate 1; the plurality of anti-tilt structures 2 correspond one-to-one to the plurality of transfer structures 3, the anti-tilt structures 2 surround the periphery of the transfer structure 3, and the orthographic projections of the anti-tilt structures 2 and the transfer structures 3 on the substrate 1 do not overlap; the distance h1 between the end face of the anti-tilt structure 2 away from the substrate 1 and the substrate 1 is greater than or equal to the distance h2 between the end face of the transfer structure 3 away from the substrate 1 and the substrate 1.

[0105] In some embodiments, the end surface of the transfer structure 3 facing away from the substrate 1 is the first surface 31. This stamp can be used to transfer LEDs (such as Micro-LED devices). The LEDs can first be fixed to a transfer substrate. Multiple transfer structures 3 then transfer the LEDs on the transfer substrate one-to-one to the driver substrate. During the stamp transfer process, the first surface 31 of the transfer structure 3 facing away from the substrate 1 is used to bond with the LEDs.

[0106] By arranging a plurality of transfer structures 3 distributed at intervals on the substrate 1, the heights of the plurality of transfer structures 3 prepared can be more consistent compared to the stamp structure in which the substrate and the protrusion are integrally formed in the related art, so that the height uniformity of the plurality of transfer structures 3 is better, which is beneficial to improving the transfer bonding yield of the light-emitting diode transferred by the stamp; by arranging a plurality of anti-tilt structures 2, and the distance h1 between the end face of the anti-tilt structure 2 away from the substrate 1 and the substrate 1 is greater than or equal to the distance h2 between the end face of the transfer structure 3 away from the substrate 1 and the substrate 1, on the one hand, the anti-tilt structure 2 can form a position limit for the entire transfer structure 3, so that the transfer structure 3 will not be tilted and deformed due to the stress difference of each part during the high-temperature and high-pressure eutectic bonding process between the light-emitting diode connection end and the drive substrate connection end; on the other hand, the anti-tilt structure 2 can adjust the position and lateral (i.e., in the direction parallel to the surface of the substrate 1) expansion and expansion of each transfer structure 3 The tension is limited so that the transfer structure 3 will not be laterally displaced relative to the substrate 1 due to thermal expansion during the high-temperature and high-pressure eutectic bonding process between the light-emitting diode connection end and the driver substrate connection end, thereby avoiding the occurrence of alignment deviation between the light-emitting diode connection end and the driver substrate connection end during the high-temperature and high-pressure eutectic bonding process; thereby improving the transfer bonding yield of the light-emitting diode transferred by the stamp; by providing at least one hole 30 in the transfer structure 3, and the hole 30 having at least a first opening 300 on the first surface 31 on the side of the transfer structure 3 away from the substrate 1, the transfer structure 3 can realize the adsorption, pickup and release of the light-emitting diode by forming different air pressures in the hole 30, thereby helping to improve the transfer efficiency of the stamp to the light-emitting diode. At the same time, based on the above-mentioned beneficial effects of the stamp, the stamp provided in the embodiment of the present disclosure can be prepared into a larger size, thereby improving the transfer bonding efficiency of the light-emitting diode transferred by the stamp.

[0107] 2 b , in some embodiments, the hole 30 penetrates the thickness of the transfer structure 3 , that is, the hole 30 is a through hole opened in the transfer structure 3 .

[0108] In some embodiments, referring to FIG2 c , another structural cross-sectional view of the stamp along the AA′ section line in FIG2 a is shown, wherein the hole 30 is a blind hole opened in the transfer structure 3 , that is, the hole 30 passes through a portion of the thickness of the transfer structure 3 .

[0109] In some embodiments, referring to Figure 2d, a top view schematic diagram of a dimensional relationship between the first surface of the transfer structure, the first opening and the second surface of the light-emitting diode in the seal of the embodiment of the present invention is shown; Figure 2e is a cross-sectional schematic diagram of a dimensional relationship between the first surface of the transfer structure, the first opening and the second surface of the light-emitting diode in the seal of the embodiment of the present invention; wherein, the light-emitting diode 4 has a second surface 41 that contacts the first surface 31 of the transfer structure 3, and the orthographic projection of the second surface 41 on the substrate 1 falls within the orthographic projection range of the first surface 31 on the substrate 1; the number of holes 30 is one; the dimension L1 of any side edge of the first surface 31 is greater than the dimension L2 of the corresponding side edge of the second surface 41, which is greater than the dimension L3 of the corresponding side edge of the first opening 300; 1 / 2 of the difference between the dimension L1 of any side edge of the first surface 31 and the dimension L3 of the corresponding side edge of the first opening 300 is greater than the alignment accuracy of the alignment equipment for aligning the light-emitting diode 4 with the transfer structure 3.

[0110] In some embodiments, referring to Figure 2f, which is a top view schematic diagram of another size relationship between the first surface of the transfer structure, the first opening and the second surface of the light-emitting diode in the seal of the embodiment of the present disclosure; the first surface 31 of the transfer structure 3 includes a middle area 301 and a peripheral area 302, and the peripheral area 302 surrounds the middle area 301; the number of holes 30 is multiple, and the first openings 300 of the multiple holes 30 are evenly distributed in the middle area 301.

[0111] In some embodiments, referring to Figure 2f, the light-emitting diode 4 has a second surface 41 that contacts the first surface 31 of the transfer structure 3, and the orthographic projection of the second surface 41 on the substrate 1 falls within the orthographic projection range of the first surface 31 on the substrate 1; the dimension L1 of any side edge of the first surface 31 is greater than the dimension L2 of the corresponding side edge of the second surface 41, which is greater than the dimension L3' of the corresponding side edge of the middle area 301; 1 / 2 of the difference between the dimension L1 of any side edge of the first surface 31 and the dimension L3' of the corresponding side edge of the middle area 301 is greater than the alignment accuracy of the alignment equipment that aligns and bonds the light-emitting diode 4 to the transfer structure 3.

[0112] The edge of the middle area 301 refers to a line formed by connecting points on the outermost edge of the first opening 300 located at the outermost periphery of the middle area 301 that are farthest from the center of the middle area 301 .

[0113] In the embodiment of the present disclosure, the setting of a single hole 30 or multiple holes 30 can ensure that, during the process of transferring the light-emitting diode by the seal, the second surface 41 of the light-emitting diode 4 covers the first opening 300 when the alignment deviation between the transfer structure 3 and the light-emitting diode 4 is the largest, thereby ensuring that a closed cavity can be formed between the hole 30 and the light-emitting diode 4, and further ensuring that the transfer structure 3 can pick up and release the light-emitting diode 4 by setting the air pressure in the hole 30, and finally realize the transfer of the light-emitting diode 4 by the transfer structure 3.

[0114] In some embodiments, referring to FIG2g , there is shown a cross-sectional view of the structure of the transfer structure in the seal of the disclosed embodiment for adsorbing the light-emitting diode; wherein the first surface 31 of the transfer structure 3 is used to contact and adhere to the second surface 41 of the light-emitting diode 4, and the distance h1 between the end face of the anti-tilt structure 2 away from the substrate 1 and the substrate 1 is less than the distance h3 between the end face of the light-emitting diode 4 away from the substrate 1 and the substrate 1. With this arrangement, during the process of the transfer structure 3 transferring the light-emitting diode 4, direct contact between the anti-tilt structure 2 and the drive substrate can be avoided, because the anti-tilt structure 2 mainly serves to position and prevent the transfer structure 3, and contact between the anti-tilt structure 2 and the drive substrate will affect the alignment and bonding between the light-emitting diode 4 and the drive substrate.

[0115] In some embodiments, referring to FIG. 2a , the orthographic projection of the anti-tilt structure 2 on the substrate 1 is annular, and the transfer structure 3 and the orthographic projection of the anti-tilt structure 2 on the substrate 1 are butted against each other. With this arrangement, the anti-tilt structure 2 can effectively limit the position, tilt, and lateral (i.e., parallel to the surface of the substrate 1) expansion of the transfer structure 3, so that the transfer structure 3 will not tilt during the high-temperature, high-pressure eutectic bonding process between the LED connection end and the driver substrate connection end, nor will it shift laterally relative to the substrate 1 due to thermal expansion, thereby avoiding alignment deviation between the LED connection end and the driver substrate connection end during the high-temperature, high-pressure eutectic bonding process; thereby improving the transfer bonding yield of the LED transfer using the stamp.

[0116] In some embodiments, referring to Figures 2a, 2h and 2i, Figure 2h is a schematic top view of the structure of another seal in an embodiment of the present disclosure; Figure 2i is a schematic top view of the structure of yet another seal in an embodiment of the present disclosure; the orthographic projection shape of the transfer structure 3 on the substrate 1 includes a circle, a rectangle, a triangle or a polygon.

[0117] In some embodiments, referring to FIG. 2 a , FIG. 2 h , and FIG. 2 i , the orthographic projection shape of the first opening 300 on the substrate 1 includes a circle, a rectangle, a triangle, or a polygon.

[0118] 2a , the shape of the first surface 31 of the transfer structure 3 is similar to or identical to the shape of the first opening 300 . 2h and 2i , the shape of the first surface 31 of the transfer structure 3 is different from the shape of the first opening 300 .

[0119] In some embodiments, referring to Figures 2b, 2j and 2k, Figure 2j is another structural cross-sectional schematic diagram of the seal along the AA' section line in Figure 2a; Figure 2k is another structural cross-sectional schematic diagram of the seal along the AA' section line in Figure 2a; wherein, the cross-sectional shape of the hole 30 perpendicular to the substrate 1 includes a rectangle (refer to Figure 2b), a trapezoid (refer to Figure 2j) or an inverted trapezoid (refer to Figure 2k).

[0120] In some embodiments, referring to Figures 2a, 2h and 2i, a plurality of raised portions 31 are arranged in an array at equal intervals; referring to Figure 2l, which is a schematic top view of the structure of another seal in the embodiment of the present disclosure; the orthographic projection shapes of the plurality of transfer structures 3 on the substrate 1 are the same, and the directions of the orthographic projection figures of any two adjacent columns of transfer structures 3 on the substrate 1 are different; as shown in Figure 2l, the orthographic projection shapes of the plurality of transfer structures 3 on the substrate 1 are all triangles, and the directions of the orthographic projection triangles of any two adjacent columns of transfer structures 3 on the substrate 1 are different; referring to Figure 2m, which is a schematic top view of the structure of another seal in the embodiment of the present disclosure; the orthographic projection shape of a portion of the plurality of transfer structures 3 on the substrate 1 is different from the orthographic projection shape of another portion on the substrate 1. As shown in Figure 2m, the orthographic projection shape of a portion of the plurality of transfer structures 3 on the substrate 1 is rectangular, and the orthographic projection shape of the other portion on the substrate 1 is circular.

[0121] In some embodiments, referring to Figure 2n, which is a schematic top view of the structure of another seal in the embodiment of the present disclosure; a part of the multiple transfer structures 3 are arranged in an array with a first interval b1, and the other part are arranged in an array with a second interval b2, and the first interval b1 is larger than the second interval b2.

[0122] In some embodiments, the transfer structure 3 is made of an elastic resin material, including any of acrylic resin, propylene glycol methyl ether acetate, silicone resin, and acrylic resin. The elastic material used in the transfer structure 3 can compensate for any discontinuity that occurs during the transfer and bonding of the LEDs, thereby improving the transfer yield of the LEDs. In this embodiment, the material of the transfer structure 3 does not require high light transmittance or high viscosity.

[0123] In some embodiments, the material of the anti-tilt structure 2 includes any one of silicon oxide, silicon nitride, silicon oxynitride, copper, aluminum, molybdenum, and silver.

[0124] In some embodiments, the height of the transfer structure 3 ranges from 4 to 15 μm. The height of the transfer structure 3 refers to its thickness in the direction away from the substrate 1. This height range ensures uniform height across the multiple transfer structures 3 on the substrate 1 and ensures good transfer of the LEDs, improving transfer yield.

[0125] In some embodiments, the width a of the annular surface of the anti-tilt structure 2 is in the range of 2 to 30 μm. This range of the annular surface width a ensures that the anti-tilt structure 2 stably restricts the position and lateral expansion (i.e., in a direction parallel to the surface of the substrate 1) of the transfer structure 3.

[0126] In some embodiments, referring to Figures 2a and 2b, the seal also includes a plurality of alignment marks 5, which are located on the side of the substrate 1 where the anti-tilt structure 2 is located, and are located in the peripheral area or the middle area of ​​the substrate 1. The alignment marks 5 do not overlap with the orthographic projections of the anti-tilt structure 2 and the transfer structure 3 on the substrate 1.

[0127] Among them, the alignment mark 5 is used to align the transfer structure 3 with the light-emitting diode when the seal picks up the light-emitting diode from the transfer substrate, and is also used to align the light-emitting diode connection end with the connection end on the driving substrate when the seal transfers the light-emitting diode to the driving substrate.

[0128] In some embodiments, the alignment mark 5 is made of a metal material, such as molybdenum, titanium, aluminum, or silver. In some embodiments, the orthographic projection of the alignment mark 5 on the substrate 1 may be rectangular, circular, or cross-shaped. The size of the alignment mark 5 can be determined based on the recognition accuracy of the alignment equipment used and is not specifically limited.

[0129] Secondly, based on the above-mentioned structure of the seal, the embodiment of the present disclosure also provides a method for preparing the seal. Referring to Figure 3, it is a flow chart of the preparation process of a seal in the embodiment of the present disclosure; wherein, it includes: Step S102: using a composition process to prepare multiple anti-tilt structures 2 on one side of the substrate 1.

[0130] Step S103 : Using a patterning process, a plurality of transfer structures 3 are prepared on one side of the substrate 1 after the above steps have been completed. The plurality of transfer structures 3 and the plurality of anti-tilt structures 2 are located on the same side of the substrate 1 .

[0131] The preparation of the plurality of transfer structures 3 includes simultaneously forming the pattern of the transfer structure 3 and the pattern of the holes 30 in the transfer structure 3 .

[0132] In this embodiment, before step S102, step S101 is further included: a patterning process is used to form a plurality of alignment marks 5 on one side of the substrate 1. The patterning process for forming the alignment marks 5 includes film deposition, photoresist coating, exposure, development, etching and other steps, which will not be repeated here.

[0133] The preparation method of the seal in the embodiment of the present disclosure is realized by a traditional patterning process. The preparation process is simple, the preparation precision is high, the preparation cost is low, and large-size seals can be prepared. The prepared seal can not only improve the transfer bonding yield of the light-emitting diode, but also improve the transfer bonding efficiency of the light-emitting diode.

[0134] In some embodiments, step S102 : preparing a plurality of anti-tilt structures 2 on one side of the substrate 1 by using a patterning process, includes: step S1021 : depositing an anti-tilt structure film on one side of the substrate.

[0135] In this step, when the anti-tilt structural film adopts an inorganic insulating material such as silicon nitride, silicon oxide or silicon oxynitride, the anti-tilt structural film is formed by chemical vapor deposition; when the anti-tilt structural film adopts a metal material such as copper, aluminum, molybdenum or silver, the anti-tilt structural film is formed by sputtering deposition.

[0136] Step S1022: coating a photoresist layer on the side of the anti-tilt structure film facing away from the substrate.

[0137] Step S1023: using a mask including an anti-tilt structure pattern to expose the photoresist layer.

[0138] Step S1024: developing and removing the photoresist in the exposed area of ​​the photoresist layer.

[0139] In this step, the photoresist layer in the area outside the anti-tilt structure pattern is developed and removed.

[0140] Step S1025: etching away the anti-tilt structure film not covered by the photoresist by dry etching or wet etching to form a plurality of anti-tilt structure patterns.

[0141] In this step, the anti-tilt structure film of the inorganic insulating material is removed by dry etching, and the anti-tilt structure film of the metal material is removed by wet etching.

[0142] Step S1026: stripping off the remaining photoresist.

[0143] In some embodiments, step S103: using a patterning process to prepare a plurality of transfer structures 3 on one side of the substrate 1 after completing the above steps, including: coating an organic resin material layer on one side of the substrate.

[0144] The organic resin material layer is exposed using a mask plate including a transfer structure pattern.

[0145] The organic resin material in the exposed area of ​​the organic resin material layer is removed by development to form a plurality of transfer structure patterns.

[0146] On the third aspect, the embodiment of the present disclosure also provides a mass transfer method. Referring to Figure 4a, it is a flow chart of a mass transfer method in the embodiment of the present disclosure; Figure 4b is a schematic diagram of the process of the seal picking up the light-emitting diode from the transfer substrate in the embodiment of the present disclosure; Figure 4c is a schematic diagram of the process of the seal transferring the light-emitting diode to the driving substrate and releasing it in the embodiment of the present disclosure; wherein, the mass transfer method includes: Step S201: in a process chamber in a first vacuum environment, the seal 6 is aligned with the transfer substrate 7 carrying a plurality of light-emitting diodes 4, and then the process chamber is restored to an atmospheric environment to realize the seal 6 picking up the light-emitting diode 4.

[0147] In this step, the air pressure in the first vacuum environment is lower than the air pressure in the atmospheric environment; the multiple transfer structures 3 in the seal 6 correspond one-to-one to at least some of the light-emitting diodes 4, and the second surface of the light-emitting diode 4 covers the first opening on the first surface of the transfer structure 3, so that the holes in the transfer structure 3 form a closed cavity.

[0148] Step S202: In the process chamber in the atmospheric environment, the stamp 6 transfers the picked-up light-emitting diode 4 to the driving substrate 8, and completes the bonding between the first connection end 42 of the light-emitting diode 4 and the second connection end 81 on the driving substrate 8, and then evacuates the process chamber to a second vacuum environment to release the light-emitting diode 4 from the stamp.

[0149] In this step, the air pressure in the second vacuum environment is lower than the air pressure in the first vacuum environment.

[0150] In the mass transfer method, during the picking process of the light-emitting diode 4, the process chamber is switched from the first vacuum environment to the atmospheric environment, so that a positive pressure is formed in the closed cavity formed between the seal 6 and the light-emitting diode 4, thereby realizing the picking of the light-emitting diode 4; during the releasing process of the light-emitting diode, the process chamber is switched from the atmospheric environment to the second vacuum environment, so that a negative pressure is formed in the closed cavity formed between the seal 6 and the light-emitting diode 4, thereby realizing the release of the light-emitting diode 4; finally, the mass transfer bonding of the light-emitting diode is realized. Compared with the related technology that requires adding a seal with a ventilation mechanism with ventilation holes to the transfer structure, the mass transfer method in this embodiment does not need to add a ventilation mechanism with ventilation holes to the transfer structure of the seal, but changes the vacuum degree of the process chamber during the transfer process of the light-emitting diode 4 to form a positive pressure or negative pressure in the closed cavity formed between the seal 6 and the light-emitting diode 4. The overall process of the mass transfer method in this embodiment is simpler.

[0151] In some embodiments, referring to Figure 4b, step S201: aligning the seal 6 with the transfer substrate 7 carrying multiple light-emitting diodes 4 in a process chamber in a first vacuum environment, and then restoring the process chamber to an atmospheric environment to enable the seal 6 to pick up the light-emitting diodes 4, including: step S2011: aligning and pressing the seal 6 and the transfer substrate 7 in the process chamber in the first vacuum environment.

[0152] In this step, the seal 6 and the transfer substrate 7 carrying the light-emitting diode 4 are aligned and pressed in a first vacuum environment. Due to the high elasticity of the transfer structure in the seal 6, the transfer structure in the seal 6 can be ensured to fit all the light-emitting diodes to be picked up. A closed cavity is formed between the hole in the transfer structure and the light-emitting diode 4. The vacuum degree in the closed cavity is p1, that is, the air pressure in the closed cavity is p1.

[0153] Step S2012: The process chamber is restored to the atmospheric environment, and negative pressure is formed in the closed cavity.

[0154] In this step, after the stamp 6 and the transfer substrate 7 are bonded, the process chamber is returned to atmospheric pressure p0. Because p1 < p0, a large negative pressure is formed in the sealed cavity between the stamp 6 and the LED 4, and the bonding interface between the stamp 6 and the LED 4 is in a strong adhesion state, and the LED is successfully picked up by the stamp 6.

[0155] Step S2013: dissociating the adhesive layer on the transfer substrate 7 for fixing the light emitting diode 4 by laser dissociation.

[0156] In this step, the adhesive layer fixed between the transfer substrate 7 and the light-emitting diode 4 can be laser scanned and irradiated by laser to achieve the dissociation of the adhesive layer; or the adhesive layer fixed between the transfer substrate 7 and the light-emitting diode 4 can be laser irradiated by laser point by point to achieve the dissociation of the adhesive layer.

[0157] Step S2014 : separating the dissociated transfer substrate 7 from the stamp 6 , and transferring the light-emitting diode 4 to the stamp 6 .

[0158] In some embodiments, referring to Figure 4c, step S202: in a process chamber in an atmospheric environment, the stamp 6 transfers the picked-up light-emitting diode 4 to the driving substrate 8, and completes the bonding of the first connection end 42 of the light-emitting diode 4 with the second connection end 81 on the driving substrate 8, and then evacuates the process chamber to a second vacuum environment to release the light-emitting diode 4 from the stamp, including: step S2021: aligning and bonding the stamp 6 carrying the light-emitting diode 4 and the driving substrate 8 in a process chamber in an atmospheric environment, so that the first connection end 42 of the light-emitting diode 4 corresponds to the second connection end 81 on the driving substrate 8.

[0159] Step S2022 : applying pressure to the stamp 6 and heating the drive substrate 8 to complete the bonding between the first connection end 42 and the second connection end 81 .

[0160] In this step, the pressure applied to the stamp 6 side refers to the pressure values ​​in Table 1; the heating temperature applied to the drive substrate 8 side refers to the temperature values ​​in Table 1. Under the pressure and heating process conditions in Table 1, the first connecting end 42 and the second connecting end 81 complete eutectic bonding.

[0161] Table 1

[0162] In some embodiments, applying pressure to the side of the stamp 6 includes: mechanical pressurization; or gas pressurization. Gas pressurization is to adjust the gas pressure in the process chamber to meet the requirements in Table 1.

[0163] In some embodiments, there are two first connection ends 42 and two second connection ends 81 , and the two first connection ends 42 and the two second connection ends 81 are connected in a one-to-one correspondence.

[0164] Step S2023: evacuate the process chamber to a second vacuum environment to form a positive pressure in the closed cavity.

[0165] In this step, after the light-emitting diode 4 is bonded to the driving substrate 8, the process chamber is evacuated and the vacuum degree inside the process chamber is adjusted to p2, that is, the air pressure in the process chamber is adjusted to p2, and p2 < p1, that is, positive pressure is achieved in the closed cavity between the stamp 6 and the light-emitting diode 4, so that the stamp 6 can complete the release action of the light-emitting diode 4.

[0166] Step S2024 : the stamp 6 is separated from the light-emitting diode 4 , and the light-emitting diode 4 is transferred to the driving substrate 8 .

[0167] The mass transfer method provided by the embodiment of the present disclosure, by adopting the stamp in the above embodiment, can not only realize the batch and multiple transfer of light-emitting diodes in the transfer substrate, but also realize the one-time transfer of multiple light-emitting diodes in the transfer substrate, thereby not only improving the transfer bonding yield of the light-emitting diodes, but also improving the transfer bonding efficiency of the light-emitting diodes.

[0168] In a fourth aspect, an embodiment of the present disclosure further provides a transfer device, comprising the seal in the above embodiment.

[0169] The transfer equipment can perform mass transfer of light-emitting diodes (LEDs), micro light-emitting diodes (Micro-LEDs) and mini light-emitting diodes (Mini-LEDs).

[0170] By adopting the stamp in the above embodiment, the transfer device can realize a one-time transfer of the light-emitting diodes on the transfer substrate, thereby improving not only the transfer bonding yield of the transfer device but also the transfer bonding efficiency of the transfer device.

[0171] It is understood that the above embodiments are merely exemplary embodiments for illustrating the principles of the present disclosure, and the present disclosure is not limited thereto. Those skilled in the art may make various modifications and improvements without departing from the spirit and substance of the present disclosure, and such modifications and improvements are also considered to be within the scope of protection of the present disclosure.

Claims

1. A seal, wherein Including substrate, A plurality of anti-tilt structures are located on one side of the substrate and are distributed at intervals; A plurality of transfer structures are located on one side of the substrate where the anti-tilt structure is located and are distributed at intervals; At least one hole is formed in the transfer structure, and the hole at least has a first opening located on a first surface of the transfer structure on a side away from the substrate; The plurality of anti-tilt structures correspond one to one with the plurality of transfer structures, The anti-tilt structure surrounds the periphery of the transfer structure, and the anti-tilt structure and the orthographic projection of the transfer structure on the substrate do not overlap; A distance between an end surface of the anti-tilt structure away from the substrate and the substrate is greater than or equal to a distance between an end surface of the transfer structure away from the substrate and the substrate.

2. The seal according to claim 1, wherein: The holes extend through the thickness of the transfer structure.

3. The seal according to claim 1, wherein: The hole is a blind hole opened in the transfer structure.

4. The seal according to claim 2 or 3, wherein: The light emitting diode has a second surface in contact with the first surface of the transfer structure, and an orthographic projection of the second surface on the substrate falls within the orthographic projection range of the first surface on the substrate; The number of the hole is one; The size of any side edge of the first surface is larger than the size of the corresponding side edge of the second surface and larger than the size of the corresponding side edge of the first opening; The size of any side edge of the first surface is equal to the size of the corresponding side edge of the first opening. 1 / 2 of the size difference is greater than the alignment accuracy of an alignment device for aligning and bonding the light-emitting diode to the transfer structure.

5. The seal according to claim 2 or 3, wherein: The first surface of the transfer structure includes a middle region and a peripheral region, the peripheral region surrounding the middle region; There are multiple holes, and the first openings of the multiple holes are evenly distributed in the middle area.

6. The seal according to claim 5, wherein: The light emitting diode has a second surface in contact with the first surface of the transfer structure, and an orthographic projection of the second surface on the substrate falls within the orthographic projection range of the first surface on the substrate; The size of any side edge of the first surface is larger than the size of the corresponding side edge of the second surface and larger than the size of the corresponding side edge of the middle area; 1 / 2 of the difference between the size of any side edge of the first surface and the size of the corresponding side edge of the middle area is greater than the alignment accuracy of an alignment device for aligning and bonding the light emitting diode to the transfer structure.

7. The seal according to claim 1, wherein: The first surface of the transfer structure is used to contact and fit with the second surface of the light-emitting diode, and the distance between the end surface of the anti-tilt structure away from the substrate and the substrate is smaller than the distance between the end surface of the light-emitting diode away from the substrate and the substrate.

8. The seal according to claim 1, wherein: The orthographic projection shape of the anti-tilt structure on the substrate is a ring. The transfer structure and the anti-tilt structure are butted against each other in orthographic projection patterns on the substrate.

9. The seal according to claim 8, wherein: The orthographic projection shape of the transfer structure on the substrate includes a circle, a rectangle, a triangle or a polygon.

10. The seal according to claim 9, wherein: The orthographic projection shape of the first opening on the substrate includes a circle, a rectangle, a triangle or a polygon.

11. The seal according to claim 9, wherein: A cross-sectional shape of the hole perpendicular to the substrate includes a rectangle, a trapezoid, or an inverted trapezoid.

12. The seal according to claim 9, wherein: The multiple transfer structures are arranged in an array at equal intervals; The orthographic projection shapes of the plurality of transfer structures on the substrate are the same, and the directions of the orthographic projection shapes of any two adjacent columns of the transfer structures on the substrate are different; Alternatively, the orthographic projection shape of a portion of the plurality of transfer structures on the substrate is different from the orthographic projection shape of another portion of the plurality of transfer structures on the substrate.

13. The seal according to claim 9, wherein: A portion of the plurality of transfer structures are arranged in an array at a first interval, and another portion are arranged in an array at a second interval, wherein the first interval is greater than the second interval.

14. The seal according to claim 1, wherein: The transfer structure is made of elastic resin material. The elastic resin material includes any one of acrylic resin, propylene glycol methyl ether acetate, silicone resin and acrylic resin.

15. The seal according to claim 1, wherein: The material of the anti-tilt structure includes any one of silicon oxide, silicon nitride, silicon oxynitride, copper, aluminum, molybdenum and silver.

16. The seal according to claim 1, wherein: The height of the transfer structure ranges from 4 to 15 μm.

17. The seal according to claim 8, wherein: The width of the annular surface of the anti-tilt structure ranges from 2 to 30 μm.

18. A transfer device, wherein: A seal comprising the seal described in any one of claims 1 to 17.

19. A method for preparing a seal, wherein: include: A plurality of anti-tilt structures are prepared on one side of the substrate by using a patterning process; Using a patterning process to prepare a plurality of transfer structures on one side of the substrate after completing the above steps; The plurality of transfer structures and the plurality of anti-tilt structures are located on the same side of the substrate; The preparing a plurality of transfer structures includes simultaneously forming a pattern of the transfer structures and a pattern of holes in the transfer structures.

20. The method for preparing a seal according to claim 19, wherein: The method of using a patterning process to prepare a plurality of anti-tilt structures on one side of the substrate includes: Depositing an anti-tilt structure film on one side of the substrate; Applying a photoresist layer on the side of the anti-tilt structure film facing away from the substrate; Exposing the photoresist layer using a mask plate including the anti-tilt structure pattern; Developing and removing the photoresist in the exposed area of ​​the photoresist layer; Etching and removing the anti-tilt structure film not covered by the photoresist by dry etching or wet etching to form patterns of the plurality of anti-tilt structures; The remaining photoresist is stripped off.

21. The method for preparing a seal according to claim 19, wherein: The method of using a patterning process to prepare a plurality of transfer structures on one side of the substrate after completing the above steps comprises: Applying an organic resin material layer on one side of the substrate; Exposing the organic resin material layer using a mask plate including the transfer structure pattern; The organic resin material in the exposed area of ​​the organic resin material layer is removed by development to form patterns of the plurality of transfer structures.

22. A method for mass transfer, wherein: include: In a process chamber in a first vacuum environment, a stamp is aligned with a transfer substrate carrying a plurality of light-emitting diodes, and then the process chamber is restored to an atmospheric environment to enable the stamp to pick up the light-emitting diodes; The air pressure in the first vacuum environment is lower than the air pressure in the atmospheric environment; the multiple transfer structures in the stamp correspond to at least part of the light-emitting diodes one by one, and the second surface of the light-emitting diode covers the first opening on the first surface of the transfer structure, so that the hole in the transfer structure forms a closed cavity; In a process chamber in an atmospheric environment, the stamp transfers the picked-up light-emitting diode to a driving substrate, and completes bonding between the first connection end of the light-emitting diode and the second connection end on the driving substrate, and then evacuates the process chamber to a second vacuum environment to release the light-emitting diode from the stamp; Wherein, the air pressure in the second vacuum environment is lower than the air pressure in the first vacuum environment.

23. The mass transfer method according to claim 22, wherein: The stamp is aligned with the transfer substrate carrying a plurality of light-emitting diodes in the process chamber in the first vacuum environment, and then the process chamber is restored to the atmospheric environment to achieve the stamp picking up the light-emitting diodes, including: Aligning and pressing the stamp and the transfer substrate in a process chamber in a first vacuum environment; Restoring the process chamber to an atmospheric environment to form a negative pressure in the closed cavity; By means of laser dissociation, the adhesive layer on the transfer substrate for fixing the light-emitting diode is dissociated; The dissociated transfer substrate is separated from the stamp, and the light emitting diode is transferred to the stamp.

24. The method for mass transfer according to claim 22, wherein: The stamp transfers the picked-up light-emitting diode to the driving substrate in the process chamber in the atmospheric environment, and completes the bonding between the first connection end of the light-emitting diode and the second connection end on the driving substrate, and then evacuates the process chamber to a second vacuum environment to release the light-emitting diode by the stamp, including: Aligning and laminating the stamp carrying the light-emitting diode with the driving substrate in a process chamber in an atmospheric environment, so that the first connecting end of the light-emitting diode is correspondingly laminating with the second connecting end on the driving substrate; Applying pressure to the stamp side and heating the drive substrate side to complete bonding between the first connection end and the second connection end; The process chamber is evacuated to the second vacuum environment, and a positive pressure is formed in the closed cavity; The stamp is separated from the light emitting diode, and the light emitting diode is transferred to the driving substrate.

25. The method for mass transfer according to claim 24, wherein: The applying pressure to the seal side comprises: Mechanical pressurization; Alternatively, the gas is pressurized.

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