CN112768370A

Movatterモバイル変換

Info

Publication number: CN112768370A
Application number: CN201911077655.8A
Authority: CN
Inventors: 董小彪; 夏继业; 曹轩
Original assignee: Chengdu Vistar Optoelectronics Co Ltd
Current assignee: Chengdu Vistar Optoelectronics Co Ltd
Priority date: 2019-11-06
Filing date: 2019-11-06
Publication date: 2021-05-07
Anticipated expiration: 2039-11-06
Also published as: CN112768370B

Abstract

The application discloses a micro-component transfer method and a micro-component transfer device, wherein the method comprises the steps of aligning a supply substrate with a micro-component with a bearing substrate, wherein one side of the supply substrate with the micro-component faces to the bearing surface of the bearing substrate, and the surface of the micro-component, which is far away from the supply substrate, is provided with an electrode; reducing the distance between the supply substrate and the bearing substrate until the electrode of the micro-component contacts the bearing surface of the bearing substrate, and simultaneously, the surface of the micro-component departing from the supply substrate except the electrode is also in direct or indirect contact with the bearing surface of the bearing substrate; removing the supply substrate after the micro-component is adhered to the bearing surface of the bearing substrate; the micro-components on the carrier substrate are transferred by means of a transfer head. Through the mode, the damage of the micro-element in the transfer process can be reduced.

Description

Transfer method and transfer device for micro-component

Technical Field

The present application relates to the field of semiconductor technology, and more particularly, to a method and apparatus for transferring a micro device.

Background

The Micro-element has wide application in the technical field of semiconductors as a Micro electric element, for example, the Micro-LED chip has the advantages of high brightness, high response speed, low power consumption, long service life and the like, and is a research hotspot of a new generation of display technology. The micro-component is usually transferred during use, the supplied substrate is peeled off during transfer, and the transferred yield is affected by the peeling force when the supplied substrate is peeled off, which easily causes problems such as breakage and chipping of the micro-component.

Disclosure of Invention

The technical problem to be solved by the present application is to provide a method and a device for transferring a micro-component, which can reduce the damage of the micro-component during the transferring process.

In order to solve the technical problem, the application adopts a technical scheme that: the method comprises aligning a supply substrate with micro-components with a carrying substrate, wherein the side of the supply substrate with the micro-components faces the carrying surface of the carrying substrate, and the surface of the micro-components departing from the supply substrate is provided with electrodes; reducing the distance between the supply substrate and the bearing substrate until the electrode of the micro-component contacts the bearing surface of the bearing substrate, and simultaneously, the surface of the micro-component departing from the supply substrate except the electrode is also in direct or indirect contact with the bearing surface of the bearing substrate; removing the supply substrate after the micro-component is adhered to the bearing surface of the bearing substrate; the micro-components on the carrier substrate are transferred by means of a transfer head.

Wherein, reducing the distance between the supply substrate and the bearing substrate until the electrode of the micro-component contacts the bearing surface of the bearing substrate comprises: and forming a groove with the shape and the size matched with the electrode of the micro-component at the position of the carrying surface of the carrying substrate corresponding to the electrode of the micro-component.

Wherein, the surface of the micro-component departing from the supply substrate except the area of the electrode and the bearing surface of the bearing substrate are also in direct contact with each other, including: the electrodes of the microcomponents contact the bottom of the groove, and the areas of the surface of the microcomponents, which faces away from the supply substrate, except for the electrodes, and the bearing surfaces outside the groove are also in direct contact with one another.

The bearing substrate comprises an adhesive layer forming a bearing surface, and the groove is formed in the adhesive layer.

Wherein, reducing the distance between the supply substrate and the bearing substrate until the electrode of the micro-component contacts the bearing surface of the bearing substrate comprises: and forming a planarization layer on one side of the micro-component with the electrode, wherein the surface of the planarization layer is flush with the surface of the electrode.

Wherein, the surface of the micro-component departing from the supply substrate, except the area of the electrode, and the bearing surface of the bearing substrate are also in mutual indirect contact, and the micro-component comprises: the electrodes and the planarization layer of the micro-component are in direct contact with the bearing surface of the bearing substrate.

Wherein, reduce the distance between supplying substrate and the supporting substrate to the electrode contact supporting substrate's of microelement bearing the loading face, the microelement deviates from also mutual indirect contact between the supporting face of the regional and supporting substrate except that the electrode of supplying the surface of substrate simultaneously includes: providing a grid plate, wherein the grid plate is provided with through holes with the shape and the size matched with the electrodes of the micro-element, and the thickness of the grid plate is equal to the height of the electrodes; placing a grid plate between a supply substrate and a carrier substrate; and the supply substrate, the grid plate and the bearing substrate are attached, so that the electrode of the micro-component is contacted with the bearing surface of the bearing substrate, and meanwhile, the area of the surface of the micro-component, which is deviated from the supply substrate and is except for the electrode, is indirectly contacted with the bearing surface of the bearing substrate through the grid plate.

Wherein, before transferring the micro-component on the bearing substrate by using the transfer head, the method comprises the following steps: the transfer heads are disposed on the transfer substrate, and the plurality of transfer heads are disposed separately from each other.

Further, disposing the transfer head on the transfer substrate, and disposing the plurality of transfer heads separately from each other includes: forming a layer of transfer head material on a transfer substrate; and patterning the transfer head material layer to form a plurality of mutually separated transfer heads.

In order to solve the above technical problem, another technical solution adopted by the present application is: the transfer device comprises a bearing substrate and a transfer substrate, wherein the bearing substrate comprises a bearing surface for bearing the micro-component; a groove with the shape and the size matched with the electrode of the micro-component is arranged on the bearing surface of the bearing substrate corresponding to the position of the electrode of the micro-component; the transfer substrate comprises at least one transfer head for adsorbing and transferring the microcomponents.

Wherein, a plurality of transfer heads are arranged on the transfer substrate, and the transfer heads are mutually separated.

The bearing substrate comprises an adhesive layer formed on the bearing surface, and the groove is formed in the adhesive layer.

The beneficial effect of this application is: different from the situation of the prior art, the electrode of the micro-component is controlled to contact the bearing surface of the bearing substrate, and meanwhile, the surface of the micro-component, which deviates from the supply substrate, is in direct or indirect contact with the bearing surface of the bearing substrate except the region of the electrode, so that the bonding area between the micro-component and the bearing substrate can be increased, the stability of the micro-component on the bearing substrate is improved, air below the micro-component can be favorably removed, and the risk of damage to the micro-component is reduced.

Drawings

FIG. 1 is a schematic flow chart of a method for transferring micro-components according to an embodiment of the present disclosure;

fig. 2 is a schematic structural view of a vertical transfer head according to an embodiment of the present application;

fig. 3 is a schematic flow chart of a method for manufacturing a discrete transfer head according to an embodiment of the present application;

FIG. 4 is a schematic structural diagram of a carrier substrate according to an embodiment of the present disclosure;

FIG. 5 is a schematic view of a transfer method for a micro-component to provide a micro-component according to another embodiment of the present application;

FIG. 6 is a schematic view of a carrier substrate provided by a method for transferring micro-components according to another embodiment of the present disclosure;

fig. 7 is a schematic view of a bonding supply substrate and a carrier substrate according to another embodiment of the present application;

FIG. 8 is a schematic view of a transfer method for micro-components for peeling off a donor substrate in another embodiment of the present application;

fig. 9 is a schematic view of a transfer head provided in a method for transferring a micro-component according to another embodiment of the present application;

FIG. 10 is a schematic view of a transfer method of a micro-component according to another embodiment of the present application;

FIG. 11 is a schematic diagram of a supply substrate configuration according to an embodiment of the present application;

fig. 12 is a schematic view of a bonding supply substrate and a carrier substrate according to a method for transferring a micro-component according to yet another embodiment of the present application;

FIG. 13 is a schematic cross-sectional view of a grid plate according to an embodiment of the present application;

FIG. 14 is a schematic top view of a grid plate according to an embodiment of the present application;

fig. 15 is a schematic view of a bonding supply substrate, a grid plate and a carrier substrate according to a method for transferring a micro-device according to still another embodiment of the present application.

Detailed Description

In order to make the purpose, technical solution and effect of the present application clearer and clearer, the present application is further described in detail below with reference to the accompanying drawings and examples.

The application provides a Micro-element transfer method which can be used for transferring Micro light emitting diode devices (Micro-LEDs), but is not limited to the Micro-LEDs, and can also be used for transferring other Micro-elements. For example, the Micro-component may be a diode Array of a Photo-diode Array detector (PDA), a MOS (Metal Oxide Semiconductor) device, a MEMS device of a Micro-Electro-Mechanical system (MEMS), or the like. In the present application, the type of micro-component is not limited, and is not limited to the examples listed herein. The transfer of Micro-LED chips will be described herein as an example.

Referring to fig. 1, fig. 1 is a schematic flow chart illustrating a micro-device transferring method according to an embodiment of the present application, and it should be noted that the present embodiment is not limited to the flow chart shown in fig. 1 if substantially the same result is obtained. As shown in fig. 1, in this embodiment, the transfer method includes the steps of:

s110: the supply substrate with the micro-components is aligned with the carrier substrate.

Wherein, one side of the supply substrate with the micro-components faces the bearing surface of the bearing substrate, and the surface of the micro-components departing from the supply substrate is provided with electrodes.

The Micro element can be a Micro-LED chip, such as a gallium nitride (GaN) -based Micro-LED chip, and can also be divided into a purple light Micro-LED chip, a blue light Micro-LED chip, a green light Micro-LED chip and the like. At present, Micro-LED chips are difficult to directly grow on a target substrate (such as a glass substrate), and the Micro-LED chips grown on a supply substrate need to be transferred onto the target substrate by means of a transfer technology.

The donor substrate may be a sapphire substrate on which Micro-LED chips of a predetermined type having a predetermined size may be grown. In other embodiments, the supply substrate may be a silicon-based substrate or the like.

The bearing substrate is made of hard materials and plays a role in fixing and bearing. For example, a glass substrate, a polymer (resin) substrate, a sapphire substrate, a ceramic substrate, or the like can be used. The carrier substrate may also be provided with an adhesive to enable the carrier substrate to bond and fix the micro-components.

S120: the distance between the supply substrate and the bearing substrate is reduced until the electrode of the micro-component contacts the bearing surface of the bearing substrate, and meanwhile, the area of the surface of the micro-component, which is far away from the supply substrate and is except the electrode, and the bearing surface of the bearing substrate are mutually in direct or indirect contact.

When the Micro-LED chips grown on the supply substrate are transferred to the target substrate, the supply substrate with the Micro-LED chips is firstly pressed on the bearing substrate, and then the supply substrate is peeled off to separate the Micro-LED chips from the supply substrate.

When a supply substrate with Micro-LED chips is pressed with a temporary bearing substrate, due to the fact that electrodes of the Micro-LED chips are relatively protruded, electrode surfaces of the LED chips are uneven, or air bubbles at the bottoms of the Micro-LED chips cannot be completely discharged, gaps exist on the joint surfaces of the supply substrate and the bearing substrate, the bottoms of the Micro-LED chips are not supported when the supply substrate is peeled off due to the existence of the gaps, stress is concentrated easily when the stress is applied, and the Micro-LED chips are not fixed enough by the bearing substrate, so that the Micro-LED chips are easily damaged when the supply substrate is peeled off. If the supply substrate is peeled off by laser, the Micro-LED chip is broken or chipped by the instantaneous shock wave generated by laser irradiation when the supply substrate is irradiated with laser.

In order to solve the technical problem, the electrodes of the micro-components are controlled to contact the bearing surface of the bearing substrate, and meanwhile, the areas of the surface of the micro-components, which is far away from the supply substrate and is except the electrodes, and the bearing surface of the bearing substrate are also in direct or indirect contact with each other. The Micro-LED chip has the advantages that no gap is formed at the joint of the bearing substrate and the supply substrate, so that the joint area between the Micro-LED chip and the bearing substrate is increased, the stability of the Micro-LED chip on the bearing substrate is improved, and the air below the Micro-LED chip is discharged, so that the risk of fragmentation of the Micro-LED chip during laser stripping is reduced.

S130: the supply substrate is removed after the micro-components are adhered to the carrying surface of the carrying substrate.

The donor substrate may be stripped using a laser, or may be stripped using a chemical etching method. After removal of the donor substrate, the micro-components remain on the carrier substrate due to adhesion.

S140: the micro-components on the carrier substrate are transferred by means of a transfer head.

The transfer head may be one or more of Polydimethylsiloxane (PDMS) transfer head, electrostatic transfer head, and vacuum transfer head, and the nature of the transfer head is not limited herein. The transfer head can be selectively engaged with portions of the micro-component to effect partial transfer. At the same time, the adhesion force of the transfer head to the micro-component should be controlled to be greater than the adhesion force of the carrier substrate to the micro-component, so that the transfer head can smoothly pick up and transfer the micro-component from the carrier substrate.

In the conventional transfer head structure, a plurality of transfer heads are integrally formed on a transfer head base of a transfer substrate, i.e., the plurality of transfer heads are connected through the transfer head base. Therefore, when the transfer head is pressed with the bearing substrate, the surface of the transfer head can deform when the surface of the base table of the transfer head deforms, and the deformation of the transfer head can cause the change of Pitch between the Micro-LED chips after being picked up, so that the follow-up process is influenced.

Referring to fig. 2, fig. 2 is a schematic structural diagram of a discrete transfer head according to an embodiment of the present disclosure. In order to solve this problem, the present application proposes a discrete transfer head whose plurality of transfer heads 50 are provided separately from each other on atransfer substrate 501. The problem of change of Pitch between Micro-LED chips during batch transfer can be solved by using the discrete transfer head, and meanwhile, the discrete transfer head can also solve the problem of thermal mismatch caused by bonding of the Micro-LED chips at the later stage.

Referring to fig. 3, fig. 3 is a schematic flow chart illustrating a method for manufacturing a discrete transfer head according to an embodiment of the present disclosure. In this embodiment, thetransfer head 50 may be a photo-lithographically-acceptable silicone material, such as UV-cured PDMS, and the discrete transfer head may be fabricated using a photolithographic process. Specifically, a layer of UV PDMS glue 502 is spin-coated on atransfer substrate 501; the paste is selectively exposed and the uncured PDMS paste is washed away with a developer solution to form a fully discretePDMS transfer head 50. The transfer substrate is made of hard material and has the function of fixing and bearing. For example, a glass substrate, a polymer (resin) substrate, a sapphire substrate, a ceramic substrate, or the like can be used. In other embodiments, the discrete transfer head may be prepared by selective coating, which is not limited herein.

In one embodiment, the carrier substrate may be processed such that the electrodes of the micro-components contact the carrying surface of the carrier substrate, and at the same time, the areas of the surface of the micro-components facing away from the donor substrate other than the electrodes and the carrying surface of the carrier substrate are also in direct contact with each other.

Referring to fig. 4, fig. 4 is a schematic structural diagram of a carrier substrate according to an embodiment of the disclosure. In this embodiment, the position of the carrying surface of the carryingsubstrate 30 corresponding to theelectrode 101 of the micro-component 10 can be processed into agroove 301 corresponding to theelectrode 101 of the micro-component 10. Therefore, when the supply substrate is attached to the bearing substrate, the electrode is accommodated by the groove to compensate the height difference between the electrode surface of the Micro-LED chip and other areas, and the joint surface is a flat surface to improve the stability of the Micro-LED chip on the bearing substrate. In addition, the groove can be used for avoiding the phenomenon that the Micro-LED chips incline on the bearing substrate, and the Micro-LED chips can be picked up conveniently during subsequent batch transfer.

The shape of the groove is matched with the shape of the electrode of the micro-element, and the size of the groove is equal to the size of the electrode of the micro-element or slightly larger than the size of the electrode of the micro-element, for example, 10% of margin can be provided, so that the alignment accuracy is improved, the alignment difficulty is reduced, and the probability of damage to the electrode is reduced. The Micro-LED chip can be divided into a vertical structure (shown in fig. 4 b) and a flip-chip structure (shown in fig. 4 a) according to the positions of the electrodes, the cathode and the anode of the Micro-LED chip in the vertical structure are located at the upper and lower sides of the chip, the cathode and the anode of the Micro-LED chip in the flip-chip structure are located at the same side of the chip, and correspondingly, the groove is also designed to correspond to one electrode or two electrodes.

In an embodiment, the carrier substrate may be directly processed, a groove may be etched on the carrier substrate, and an adhesive may be further filled in the groove to enhance the adhesive force to the Micro-LED chip, where the size of the groove is to reserve a space for the adhesive, that is, to ensure that the size of the space after the adhesive is filled is greater than or equal to the size of the electrode. In another embodiment, the adhesive layer may be formed on the carrier substrate in a whole layer, and then the groove may be directly formed on the adhesive layer, where the arrangement form of the groove is not limited herein.

Referring to fig. 5-10, the transfer method of the micro-device will be described in detail as follows:

referring to fig. 5, fig. 5 is a schematic diagram of a transfer method of a micro device according to another embodiment of the present application. In this embodiment, a plurality ofMicro-LED chips 10 are sequentially arranged on thesupply substrate 20, the Micro-LED chips 10 are shown as a flip-chip structure, and the cathodes and anodes of theMicro-LED chips 10 are formed on the first surface remote from thesupply substrate 20. In other embodiments, theMicro-LED chip 10 may also be a vertical structure, and the cathode and the anode of the Micro-LED chip in the vertical structure are located on the upper and lower sides of the chip.

Referring to fig. 6, fig. 6 is a schematic view of a carrier substrate provided by a method for transferring a micro device according to another embodiment of the present disclosure. In this embodiment, thecarrier substrate 30 is a glass substrate, and theadhesive layer 302 is disposed on thecarrier substrate 30, and the adhesive layer may be a nano-imprintable adhesive material layer, such as a silicone material layer. The adhesive layer may be processed by using a nano-imprinting or photolithography technique to form agroove 301 corresponding to the shape of theelectrode 101 at a position corresponding to theelectrode 101 of the Micro-LED chip, wherein the size of the groove is slightly larger than that of theelectrode 101. By adopting the arrangement, the bonding area between the Micro-LED chip and the bearing substrate is increased, the stability of the Micro-LED chip on the bearing substrate is improved, and air below the Micro-LED chip is discharged, so that the risk of cracking of the Micro-LED chip during laser stripping is reduced.

Referring to fig. 7, fig. 7 is a schematic view illustrating a bonding of a supply substrate and a carrier substrate according to another embodiment of the present application. In this embodiment, thesupply substrate 20 and thecarrier substrate 30 are aligned and bonded, so that the electrodes of the Micro-LED chip are sunk into the grooves of the carrier substrate and bonded to the carrier surface of thecarrier substrate 30, and since the grooves compensate for the height difference between the electrode surfaces and other regions, the other regions of the Micro-LED chip except the electrodes are also in direct contact with the carrier surface outside the grooves.

Referring to fig. 8, fig. 8 is a schematic diagram of a method for transferring a micro device to a substrate for stripping the substrate. Thesupply substrate 20 is laser stripped and the laser strippedsupply substrate 20 is removed leaving theMicro-LED chip 10 on thecarrier substrate 30. In other embodiments, the stripping may be performed by other stripping methods such as chemical etching.

Referring to fig. 9, fig. 9 is a schematic view of a transfer head provided in a method for transferring a micro device according to another embodiment of the present application. In this embodiment, atransfer head 50 is provided, thetransfer head 50 is a discrete transfer head, and thetransfer head 50 is attached to theMicro-LED chip 10, so that theMicro-LED chip 10 is fixed by thetransfer head 50. Thetransfer head 50 is moved to pick up theMicro-LED chip 10.

Referring to fig. 10, fig. 10 is a schematic view illustrating a transfer method of a micro device according to another embodiment of the present application. In this embodiment, atarget substrate 60 is provided, a driving circuit and acontact electrode 601 are provided on thetarget substrate 60, thetransfer head 50 is aligned and bonded to thetarget substrate 60, and the cathode and anode of theMicro-LED chip 10 are connected to thecontact electrode 601. Therefore, the Micro-LED chip is transferred.

In this embodiment, when the Micro-LED chip is in a flip-chip structure, after the Micro-LED chip is bonded to the target substrate, the Micro-LED chip may be packaged, and a package layer is formed on the Micro-LED chip to protect the Micro-LED chip and the contact electrode. The specific packaging material and packaging process may be conventional materials and processes, and are not limited herein.

In another embodiment, when the Micro-LED chip is a vertical structure, the anode and cathode are located on the upper and lower sides of the chip, and after the chip is transferred, an electrode on the other side needs to be fabricated. The specific manufacturing method can adopt a conventional process, and is not limited herein.

In another embodiment, the donor substrate may be treated to achieve that the electrodes of the microcomponents contact the carrying surface of the carrying substrate, and at the same time that the areas of the surface of the microcomponents facing away from the donor substrate other than the electrodes and the carrying surface of the carrying substrate are also in indirect contact with each other.

Referring to fig. 11, fig. 11 is a schematic structural diagram of a supply substrate according to an embodiment of the present application. In this embodiment, aplanarization layer 70 may be formed on the side of thesupply substrate 20 having the micro-components 10, and the surface of theplanarization layer 70 is flush with the surface of the electrodes of the micro-components 10.

In this embodiment, the planarization layer is provided to fill up the height difference between the electrode of the micro-component and the other regions of the micro-component, so that the surface of the supply substrate is a plane, which not only increases the bonding area between the supply substrate and the carrier substrate, improves the stability of the micro-component on the carrier substrate, but also facilitates the removal of air below the micro-component, thereby reducing the risk of cracking the micro-component during laser lift-off. Meanwhile, the alignment of the supply substrate and the bearing substrate can be avoided, so that the laminating effect is better.

In one embodiment, the planarization layer can be made of inorganic compound, organic photoresist, etc., such as silicon dioxide, silicon nitride, SU-8, etc. The planarization layer may be formed using spin coating, ink jet printing, evaporation, deposition, and the like.

Referring to fig. 5 and 12, the transfer method of the micro-device will be described in detail as follows:

referring to fig. 5, asupply substrate 20 withMicro-LED chips 10 is provided.

A layer of photoresist is spin-coated or a layer of inorganic oxide is vapor-deposited on thesupply substrate 20 to form a planarization layer, and the height of the planarization layer is flush with the height of the electrodes of the Micro-LED chip. And patterning the planarization layer to expose the electrodes of the Micro-LED chip.

Referring to fig. 12, fig. 12 is a schematic view illustrating a supply substrate and a carrier substrate attached to each other according to a transfer method of a micro device in another embodiment of the present application.

Providing abearing substrate 30, forming anadhesive layer 302 on the bearingsubstrate 30, attaching thesupply substrate 20 and the bearingsubstrate 30, and enabling the electrode and the planarization layer of the Micro-LED chip to be in direct contact with the bearing surface of the bearing substrate. In this embodiment, the surface of the carrier substrate is a flat surface without the grooves/protrusions, and correspondingly, the adhesive layer is also a flat surface.

Then, the steps of laser lift-off, pick-up transfer, etc. are performed, which are the same as those in the above embodiments, please refer to the description of the above embodiments, and are not described herein again.

In a further embodiment, it is also possible to use other auxiliary tools to bring the electrodes of the microcomponents into contact with the carrying surface of the carrying substrate, while at the same time the areas of the surface of the microcomponents facing away from the donor substrate other than the electrodes and the carrying surface of the carrying substrate are also in indirect contact with one another.

Referring to fig. 13 and 14 in combination, fig. 13 is a schematic cross-sectional structure diagram of a grid plate according to an embodiment of the present application, and fig. 14 is a schematic top-view structure diagram of the grid plate according to the embodiment of the present application. In this embodiment, a grid plate is provided, thegrid plate 80 has throughholes 801 with shape and size matching with the electrodes of the micro-components, the arrangement of the throughholes 801 corresponds to the position arrangement of the electrodes of the micro-components, and the thickness of thegrid plate 80 is equal to the height of the electrodes of the micro-components.

Referring to fig. 15, fig. 15 is a schematic view illustrating a bonding of a supply substrate, a grid plate and a carrier substrate according to a transfer method of a micro device in yet another embodiment of the present application. Before the supply substrate is attached to the bearing substrate, thegrid plate 80 is placed between thesupply substrate 20 and the bearingsubstrate 30, thesupply substrate 20, thegrid plate 80 and the bearingsubstrate 30 are attached, so that the height difference between the electrode of the micro-component and other areas is filled up by the grid plate, the surface of the supply substrate is a plane, the combination area of the bearing substrate and the supply substrate is increased, the stability of the micro-component is improved, air below the micro-component is favorably exhausted, and the risk of damaging the micro-component is reduced.

The grid plate may be made of an organic material and may have a certain viscosity, which may serve to bond the donor substrate to the carrier substrate. In this case, the adhesive layer may no longer be provided on the carrier substrate.

In the embodiment, by utilizing the independent grid plate, the supply substrate or the bearing substrate does not need to be processed, the transfer process is reduced, and the micro-element can be repeatedly used under the condition that the structure and the arrangement mode of the micro-element are the same, so that the micro-element is more flexible and convenient.

In the embodiment, in the micro-component transferring process, the height difference between the electrode surface of the micro-component and other areas is compensated, the combination area of the supply substrate and the bearing substrate can be increased, the stability of the micro-component on the bearing substrate is improved, and the air below the micro-component is favorably discharged, so that the risk of the micro-component cracking during laser stripping is reduced, and the transfer yield is improved.

Referring to fig. 2 and fig. 4, based on the above-mentioned micro device transferring method, the present application further provides a micro device transferring apparatus, which includes acarrier substrate 30 and a transferringsubstrate 501.

Thecarrier substrate 30 is provided withrecesses 301, which recesses 301 are adapted to the shape and size of theelectrodes 101 of themicrocomponents 10 supplied on the substrate. Therefore, when the supply substrate is attached to the bearing substrate, the electrode is accommodated by the groove to compensate the height difference between the electrode surface of the Micro-LED chip and other areas, and the joint surface is a flat surface to improve the stability of the Micro-LED chip on the bearing substrate. In addition, the groove can be used for avoiding the phenomenon that the Micro-LED chips incline on the bearing substrate, and the Micro-LED chips can be picked up conveniently during subsequent batch transfer. Please refer to the description of the above embodiments, which is not repeated herein.

Thetransfer substrate 501 comprises at least onetransfer head 50 for adsorbing and transferring microcomponents. Specifically, a plurality of transfer heads 50 are provided on thetransfer substrate 501, and the plurality of transfer heads 50 are provided separately from each other. The problem of change of Pitch between Micro-LED chips during batch transfer can be solved by using the discrete transfer head, and meanwhile, the discrete transfer head can also solve the problem of thermal mismatch caused by bonding of the Micro-LED chips at the later stage. Please refer to the description of the above embodiments, which is not repeated herein.

Referring to fig. 11, based on the above-mentioned micro device transfer method, the present application further provides asupply substrate 20, wherein aplanarization layer 70 is disposed on one side of thesupply substrate 30 having themicro device 10, and a surface of theplanarization layer 70 is flush with a surface of an electrode of the micro device. By arranging the flattening layer, the height difference between the electrode of the micro-component and other areas of the micro-component can be filled, so that the surface of the supply substrate is a plane, the combination area of the supply substrate and the bearing substrate can be increased, the stability of the micro-component on the bearing substrate is improved, air below the micro-component can be favorably discharged, and the risk of cracking of the micro-component during laser stripping is reduced. Meanwhile, the alignment of the supply substrate and the temporary substrate can be avoided, so that the laminating effect is better. Please refer to the description of the above embodiments, which is not repeated herein.

The above description is only for the purpose of illustrating embodiments of the present application and is not intended to limit the scope of the present application, and all modifications of equivalent structures and equivalent processes, which are made by the contents of the specification and the drawings of the present application or are directly or indirectly applied to other related technical fields, are also included in the scope of the present application.

Claims

1. A method for transferring a micro-component, comprising:

aligning a supply substrate with micro-components with a bearing substrate, wherein one side of the supply substrate with the micro-components faces to the bearing surface of the bearing substrate, and the surface of the micro-components, which is far away from the supply substrate, is provided with an electrode;

reducing the distance between the supply substrate and the bearing substrate until the electrodes of the micro-components contact the bearing surface of the bearing substrate, and simultaneously, the areas of the surface of the micro-components, which are away from the supply substrate and except the electrodes, and the bearing surface of the bearing substrate are also in direct or indirect contact with each other;

removing the supply substrate after the micro-components are adhered to the carrying surface of the carrying substrate;

and transferring the micro-component on the bearing substrate by using a transfer head.

2. A method for transferring microcomponents in accordance with claim 1, wherein said step of reducing the distance between the donor substrate and the carrier substrate until the electrodes of the microcomponents contact the carrying surface of the carrier substrate comprises:

forming a groove with the shape and the size matched with the electrode of the micro-component at the position, corresponding to the electrode of the micro-component, of the bearing surface of the bearing substrate;

the direct contact between the areas of the surface of the micro-components facing away from the supply substrate, except for the electrodes, and the carrying surface of the carrying substrate comprises:

the electrodes of the microcomponents contact the bottom of the groove, while the areas of the surface of the microcomponents facing away from the donor substrate, excluding the electrodes, and the bearing surface outside the groove are also in direct contact with one another.

3. The method of claim 2, wherein the carrier substrate comprises an adhesive layer forming the carrier surface, the recesses being provided on the adhesive layer.

4. A method for transferring microcomponents in accordance with claim 1, wherein said step of reducing the distance between the donor substrate and the carrier substrate until the electrodes of the microcomponents contact the carrying surface of the carrier substrate comprises:

forming a planarization layer on one side of the micro-component with the electrode, wherein the surface of the planarization layer is flush with the surface of the electrode;

the indirect contact between the areas of the surface of the micro-components facing away from the supply substrate, other than the electrodes, and the carrying surface of the carrying substrate also comprises:

the electrodes and the planarization layer of the micro-component are in direct contact with the bearing surface of the bearing substrate.

5. A method according to claim 1, wherein said reducing the distance between the supply substrate and the carrier substrate until the electrodes of the microcomponents contact the carrying surface of the carrier substrate, while the areas of the surface of the microcomponents facing away from the supply substrate other than the electrodes and the carrying surface of the carrier substrate are also in indirect contact with each other comprises:

providing a grid plate having through holes with shape and size matching with the electrodes of the micro-components, the thickness of the grid plate being equal to the height of the electrodes;

placing the grid plate between the donor substrate and the carrier substrate;

and attaching the supply substrate, the grid plate and the bearing substrate to enable the electrode of the micro-component to contact the bearing surface of the bearing substrate, and simultaneously enabling the area of the surface of the micro-component, which deviates from the supply substrate, except the electrode to indirectly contact with the bearing surface of the bearing substrate through the grid plate.

6. The method for transferring microcomponents as claimed in claim 1, characterized in that before transferring the microcomponents on the carrier substrate by means of a transfer head, it comprises:

the transfer heads are disposed on a transfer substrate, and the plurality of transfer heads are disposed separately from each other.

7. The method of claim 6, wherein the disposing the transfer heads on the transfer substrate and the disposing the transfer heads separately from each other comprises:

forming a layer of transfer head material on the transfer substrate;

and patterning the transfer head material layer to form a plurality of mutually-separated transfer heads.

8. A transfer device for micro-components, comprising,

the bearing substrate comprises a bearing surface for bearing the micro-element;

a transfer substrate comprising at least one transfer head for adsorbing and transferring said microcomponents;

and a groove with the shape and the size matched with the electrode of the micro-element is arranged at the position, corresponding to the electrode of the micro-element, of the bearing surface.

9. The micro-component transfer device according to claim 8, wherein a plurality of the transfer heads are provided on the transfer substrate, and the plurality of transfer heads are provided separately from each other.

10. A device for transferring microcomponents as claimed in claim 8 or 9, characterized in that the carrier substrate comprises an adhesive layer formed on the carrier surface, the recesses being provided in the adhesive layer.