Mass transfer device and mass transfer method

Abstract

The invention discloses a mass transfer device and a mass transfer method, and relates to the technical field of device processing. The mass transfer device comprises a substrate and a plurality of ultrasonic hot-pressing pixel modules arranged on the substrate. The ultrasonic hot-pressing pixel module comprises a first thin film transistor switch, a second thin film transistor switch, an ultrasonic generation unit and a hot-pressing generation unit, the ultrasonic generation unit is electrically connected with the first thin film transistor switch, and the hot-pressing generation unit is electrically connected with the second thin film transistor switch. Through the first thin film transistor switch and the second thin film transistor switch, the ultrasonic wave generation unit and the hot pressing generation unit can be reliably and efficiently controlled independently, so that hot pressing and ultrasonic treatment are achieved. Therefore, according to the mass transfer device and the mass transfer method using the mass transfer device in the embodiment of the invention, the mass transfer efficiency of chips can be improved, and meanwhile, the mass transfer yield can also be ensured.

Description

Technical Field

[0001] The present application relates to the field of device processing technology, and in particular, to a mass transfer device and a mass transfer method. Background Art

[0002] At present, Micro LED display technology has become one of the current hot technologies because of its advantages such as high brightness, low power consumption, high resolution, long life, high color saturation, and wide viewing angle. One of the mainstream technical routes at this stage is to miniaturize the LED and transfer it to the corresponding control array substrate to achieve the individual drive and control of each LED, so as to achieve the display effect. The biggest technical bottleneck restricting the development of Micro LED technology now lies in the mass transfer technology, that is, how to selectively transfer millions of Micro LEDs to the control array substrate in a short period of time, and form a good bond with the substrate to achieve the individual control and drive of each Micro LED. In the related technology, the devices and processes used to achieve mass transfer of chips still need to be improved in terms of transfer efficiency. Summary of the invention

[0003] The present application provides a mass transfer device and a mass transfer method, which can improve the efficiency of mass transfer.

[0004] The embodiments of the present application can be implemented as follows:

[0005] In a first aspect, the present application provides a mass transfer device, comprising a substrate and a plurality of ultrasonic and thermal pressure pixel modules arranged on the substrate; the ultrasonic and thermal pressure pixel modules comprise a first thin film transistor switch, a second thin film transistor switch, an ultrasonic wave generating unit and a thermal pressure generating unit, the ultrasonic wave generating unit is electrically connected to the first thin film transistor switch, the thermal pressure generating unit is electrically connected to the second thin film transistor switch, the first thin film transistor switch is used to control the ultrasonic wave generating unit to output ultrasonic waves, and the second thin film transistor switch is used to control the thermal pressure generating unit to output heat and to control the deformation of the thermal pressure generating unit in a preset direction.

[0006] In an optional embodiment, the ultrasonic thermal pressure pixel module also includes a common electrode, the ultrasonic wave generating unit includes a first anode and a first cathode, one of the first anode and the first cathode is electrically connected to the first thin-film transistor switch, and the other is electrically connected to the common electrode; the thermal pressure generating unit includes a second anode and a second cathode, one of the second anode and the second cathode is electrically connected to the second thin-film transistor switch, and the other is electrically connected to the common electrode.

[0007] In an optional embodiment, the first thin-film transistor switch includes a first gate, a first source and a first drain, and the second thin-film transistor switch includes a second gate, a second source and a second drain, wherein the first anode is electrically connected to the first drain, the second anode is electrically connected to the second drain, and the first cathode and the second cathode are both electrically connected to the common electrode.

[0008] In an optional embodiment, the ultrasonic generating unit includes a piezoelectric material layer, and the piezoelectric material layer is connected to the first anode and the first cathode.

[0009] In an optional embodiment, a portion of the first anode, the piezoelectric material layer, and a portion of the first cathode are stacked in sequence in a preset direction.

[0010] In an optional embodiment, the thermal pressure generating unit includes a thermosensitive material layer and an electrothermal structure, the second anode and the second cathode are both electrically connected to the electrothermal structure, and the electrothermal structure is connected to the thermosensitive material layer.

[0011] In an optional embodiment, the electric heating structure is embedded in the heat-sensitive material layer and extends in a circuitous manner.

[0012] In an optional embodiment, the mass transfer device includes a flat layer, which is stacked on a side of the first thin-film transistor switch and the second thin-film transistor switch away from the substrate, the ultrasonic generating unit and the hot pressure generating unit are both arranged on a side of the flat layer away from the substrate, the first anode or the first cathode passes through the flat layer and is electrically connected to the first thin-film transistor switch, and the second anode or the second cathode passes through the flat layer and is electrically connected to the second thin-film transistor switch; in an optional embodiment, the common electrode is embedded in the flat layer.

[0013] In an optional embodiment, the ultrasonic generating unit surrounds the outside of the hot pressing generating unit to form a closed structure, the side of the ultrasonic generating unit away from the substrate forms an ultrasonic output surface, the side of the hot pressing generating unit away from the substrate forms a hot pressing surface, and the distance between the ultrasonic output surface and the substrate is smaller than the distance between the hot pressing surface and the substrate.

[0014] In a second aspect, the present application provides a mass transfer method, using the mass transfer device of any one of the aforementioned embodiments, the mass transfer method comprising:

[0015] Obtaining a temporary substrate carrying a chip, wherein pins of the chip face away from the temporary substrate;

[0016] The side of the temporary substrate facing away from the chip is attached to the ultrasonic thermal compression pixel module of the mass transfer device, and each chip is opposite to an ultrasonic thermal compression pixel module in the thickness direction of the temporary substrate;

[0017] Obtain a target substrate, align the pads on the target substrate with the pins of the chip, and reserve a gap between the pads and the pins;

[0018] The ultrasonic wave generating unit and the hot pressing generating unit of at least one ultrasonic hot pressing pixel module are turned on, so that under the action of hot pressing and ultrasound, the pins of the chip abut against and bond with the pads to form an electrical connection.

[0019] The beneficial effects of the embodiments of the present application include:

[0020] The mass transfer device of the present application includes a substrate and several ultrasonic hot pressing pixel modules arranged on the substrate; the ultrasonic hot pressing pixel module includes a first thin film transistor switch, a second thin film transistor switch, an ultrasonic generating unit and a hot pressing generating unit, the ultrasonic generating unit is electrically connected to the first thin film transistor switch, the hot pressing generating unit is electrically connected to the second thin film transistor switch, the first thin film transistor switch is used to control the ultrasonic generating unit to output ultrasonic waves, and the second thin film transistor switch is used to control the hot pressing generating unit to output heat and control the deformation of the hot pressing generating unit in a preset direction. In the embodiment of the present application, the ultrasonic hot pressing pixel module has the functions of hot pressing and ultrasonic treatment, and a chip can be bonded to the target substrate under hot pressing and ultrasonic action by controlling an ultrasonic hot pressing pixel module. Moreover, through the first thin film transistor switch and the second thin film transistor switch, the ultrasonic generating unit and the hot pressing generating unit can be independently controlled reliably and efficiently to achieve hot pressing and ultrasonic treatment. Therefore, the mass transfer device of the embodiment of the present application and the mass transfer method using the mass transfer device can improve the efficiency of chip mass transfer, and also can ensure the yield of mass transfer. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 A schematic diagram of a mass transfer device in one embodiment of the present application;

[0023] Figure 2 This is a cross-sectional view of an ultrasonic thermal compression pixel module in an embodiment of the present application at a first viewing angle;

[0024] Figure 3 This is a cross-sectional view of an ultrasonic thermal compression pixel module in an embodiment of the present application at a second viewing angle;

[0025] Figure 4 This is a flow chart of a mass transfer method in one embodiment of the present application;

[0026] Figure 5 This is a schematic diagram of a temporary substrate carrying a chip in one embodiment of the present application;

[0027] Figure 6 This is a schematic diagram of a temporary substrate attached to a mass transfer device in one embodiment of the present application;

[0028] Figure 7 This is a schematic diagram of a target substrate before bonding with a chip in one embodiment of the present application;

[0029] Figure 8 This is a schematic diagram of the bonding process between the target substrate and the chip in one embodiment of the present application.

[0030] Icon: 100-substrate; 101-ultrasonic hot pressing pixel module; 210-first thin film transistor switch; 211-first gate; 212-first source; 213-first drain; 214-first active layer; 220-second thin film transistor switch; 221-second gate; 222-second source; 223-second drain; 224-second active layer; 230-gate insulating layer; 240-protective layer; 300-ultrasonic generating unit; 301-ultrasonic output surface; 310-first anode; 320-first cathode; 330-piezoelectric material layer; 400-hot pressing generating unit; 410-second anode; 420-second cathode; 430-thermosensitive material layer; 440-electric heating structure; 401-hot pressing surface; 500-common electrode; 600-flat layer; 610-first flat layer; 620-second flat layer;

[0031] 10-temporary substrate; 20-chip; 21-pin; 30-target substrate; 31-pad. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0033] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for protection, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0034] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0035] In the description of the present application, it should be noted that if the terms "upper", "lower", "inside", "outside", etc. appear to indicate an orientation or position relationship, it is based on the orientation or position relationship shown in the drawings, or is the orientation or position relationship in which the product of the invention is usually placed when used. It is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0036] In addition, the terms “first”, “second”, etc., if used, are merely used to distinguish between the descriptions and should not be understood as indicating or implying relative importance.

[0037] It should be noted that, in the absence of conflict, the features in the embodiments of the present application may be combined with each other.

[0038] As mentioned above, the current mass transfer technology has the problem of low efficiency due to equipment and process limitations. To this end, the embodiment of the present application provides a mass transfer device and a mass transfer method using the mass transfer device. By setting multiple ultrasonic hot pressing pixel modules 101 in the mass transfer device, the ultrasonic hot pressing pixel module 101 includes an ultrasonic generating unit 300 and a hot pressing generating unit 400, so each ultrasonic hot pressing pixel module 101 can perform hot pressing and ultrasonic treatment on the chip 20, so that the transfer efficiency of the chip 20 is improved.

[0039] Figure 1 A schematic diagram of a mass transfer device in one embodiment of the present application; Figure 2 This is a cross-sectional view of an ultrasonic thermal compression pixel module 101 at a first viewing angle in an embodiment of the present application; Figure 3 This is a cross-sectional view of the ultrasonic thermal compression pixel module 101 in one embodiment of the present application at a second viewing angle. Figures 1 to 3As shown, the mass transfer device provided in the embodiment of the present application includes a substrate 100 and a plurality of ultrasonic and hot pressure pixel modules 101 arranged on the surface of the substrate 100. In the present embodiment, each ultrasonic and hot pressure pixel module 101 is arranged on the same surface of the substrate 100. The ultrasonic and hot pressure pixel module 101 includes a first thin-film transistor switch 210, a second thin-film transistor switch 220, an ultrasonic generating unit 300 and a hot pressure generating unit 400. The ultrasonic generating unit 300 is used to convert electrical energy into ultrasonic waves, and the hot pressure generating unit 400 is used to convert electrical energy into heat and deformation in a preset direction. The first thin-film transistor switch 210 is used to control the ultrasonic generating unit 300 to output ultrasonic waves, and the second thin-film transistor switch 220 is used to control the hot pressure generating unit 400 to output heat and control the deformation of the hot pressure generating unit 400 in a preset direction. In the embodiment of the present application, the ultrasonic generating unit 300 can Figure 8 ) for ultrasonic treatment, and the heat pressure generating unit 400 can press the chip 20 against the target substrate 30 (see Figure 8 ), and provide heat; the ultrasonic generating unit 300 and the hot pressing generating unit 400 can jointly realize the bonding of the chip 20 and the target substrate 30. Specifically, the ultrasonic wave generated by the ultrasonic generating unit 300 provides energy for ultrasonic welding, which can reduce the temperature required for welding. Under the combined action of ultrasonic wave, heat and pressure, the surfaces of the materials to be welded together diffuse and recrystallize with each other, thereby achieving a bonding effect. In this embodiment, the ultrasonic hot pressing pixel module 101 can be arranged on the substrate 100 in a rectangular array.

[0040] In this embodiment, the preset direction is perpendicular to the substrate 100. The heat pressure generating unit 400 can expand and deform in a direction perpendicular to the substrate 100, so that it can push the chip 20 away from the substrate 100, thereby pressing the chip 20 against the target substrate 30. It should be understood that in some cases, the thermal deformation direction of the heat pressure generating unit 400 is not limited to the direction perpendicular to the substrate 100, and there may also be thermal deformation in other directions (such as a direction parallel to the substrate 100).

[0041] In the embodiment of the present application, the ultrasonic generating unit 300 surrounds the outer side of the hot pressing generating unit 400 and forms a closed structure. The ultrasonic generating unit 300 forms an ultrasonic output surface 301 on the side away from the substrate 100, and the hot pressing surface 401 is formed on the side away from the substrate 100. The distance between the ultrasonic output surface 301 and the substrate 100 is smaller than the distance between the hot pressing surface 401 and the substrate 100. By making the distance between the ultrasonic output surface 301 and the substrate 100 smaller than the distance between the hot pressing surface 401 and the substrate 100, when the temporary substrate 10 carrying the chip 20 is attached to the mass transfer device, the hot pressing surface 401 of the hot pressing generating unit 400 can first attach to the temporary substrate 10 (abut), and the ultrasonic generating unit 300 will not directly contact the temporary substrate 10, and the ultrasonic output surface 301 and the temporary substrate 10 maintain a certain distance. By surrounding the ultrasonic generating unit 300 on the outside of the hot pressing generating unit 400, the ultrasonic generating unit 300 can more evenly output ultrasonic waves to the front area (that is, the area corresponding to the chip 20) of the hot pressing surface 401 of the hot pressing generating unit 400, thereby achieving a better bonding effect. Specifically in this embodiment, the hot pressing surface 401 is a rectangular surface, and the ultrasonic generating unit 300 surrounds the hot pressing generating unit 400 to form a rectangle. There is a gap between the hot pressing generating unit 400 and the ultrasonic generating unit 300 to prevent the hot pressing generating unit 400 from interfering with the ultrasonic generating unit 300 when it is deformed by heat.

[0042] Furthermore, the ultrasonic thermal pressure pixel module 101 further includes a common electrode 500, the ultrasonic wave generating unit 300 includes a first anode 310 and a first cathode 320, one of the first anode 310 and the first cathode 320 is electrically connected to the first thin film transistor switch 210, and the other is electrically connected to the common electrode 500; the thermal pressure generating unit 400 includes a second anode 410 and a second cathode 420, one of the second anode 410 and the second cathode 420 is electrically connected to the second thin film transistor switch 220, and the other is electrically connected to the common electrode 500. A thin film transistor (TFT) switch is an electronic switch based on thin film transistor technology, which can be applied to switch control of a large number of densely distributed devices.

[0043] Specifically, the first thin film transistor switch 210 includes a first gate electrode 211, a first source electrode 212 and a first drain electrode 213, and the second thin film transistor switch 220 includes a second gate electrode 221, a second source electrode 222 and a second drain electrode 223, wherein the first anode electrode 310 is electrically connected to the first drain electrode 213, the second anode electrode 410 is electrically connected to the second drain electrode 223, and the first cathode electrode 320 and the second cathode electrode 420 are both electrically connected to the common electrode 500. In this embodiment, the first drain electrode 213 and the second drain electrode 223 can provide driving current to the ultrasonic generating unit 300 and the heat pressure generating unit 400 respectively; and the common electrode 500 collects the current flowing from the ultrasonic generating unit 300 and the heat pressure generating unit 400.

[0044] In this embodiment, the first gate electrode 211 and the second gate electrode 221 are connected to the substrate 100, and the substrate 100, the first gate electrode 211 and the second gate electrode 221 are covered with a gate insulating layer 230. The first thin film transistor switch 210 further includes a first active layer 214, which covers a position on the gate insulating layer 230 corresponding to the first gate electrode 211, a portion of the first active layer 214 is located between the first source electrode 212 and the gate insulating layer 230, and another portion of the first active layer 214 is located between the first drain electrode 213 and the gate insulating layer 230. A portion of the first source electrode 212 is covered on the first active layer 214, and another portion is covered on the gate insulating layer 230; a portion of the first drain electrode 213 is covered on the first active layer 214, and another portion is covered on the gate insulating layer 230; the first source electrode 212 and the first drain electrode 213 are spaced apart. The second thin film transistor switch 220 further includes a second active layer 224, which covers a position on the gate insulating layer 230 corresponding to the second gate 221, a portion of the second active layer 224 is located between the second source 222 and the gate insulating layer 230, and another portion of the second active layer 224 is located between the second drain 223 and the gate insulating layer 230. A portion of the second source 222 covers the second active layer 224, and another portion covers the gate insulating layer 230; a portion of the second drain 223 covers the second active layer 224, and another portion covers the gate insulating layer 230; the second source 222 is spaced from the second drain 223. Further, the first thin film transistor switch 210 and the second thin film transistor switch 220 are also covered with a protective layer 240 on the side facing away from the substrate 100.

[0045] It should be understood that the specific structures of the first thin film transistor switch 210 and the second thin film transistor switch 220 may refer to the prior art and are not limited to the structural features introduced in the above embodiments.

[0046] In this embodiment, the mass transfer device includes a flat layer 600, which is stacked on the side of the first thin film transistor switch 210 and the second thin film transistor switch 220 away from the substrate 100. Specifically, the flat layer 600 is arranged on the side of the protective layer 240 away from the substrate 100. The ultrasonic generating unit 300 and the hot pressure generating unit 400 are both arranged on the side of the flat layer 600 away from the substrate 100. The first anode 310 or the first cathode 320 (specifically the first anode 310 in this embodiment) passes through the flat layer 600 and the protective layer 240 and is electrically connected to the first drain 213 of the first thin film transistor switch 210. The second anode 410 or the second cathode 420 (specifically the second anode 410 in this embodiment) passes through the flat layer 600 and the protective layer 240 and is electrically connected to the second drain 223 of the second thin film transistor switch 220.

[0047] In this embodiment, the common electrode 500 is embedded in the planar layer 600. Specifically, the planar layer 600 includes a first planar layer 610 and a second planar layer 620 stacked in a preset direction, wherein the first planar layer 610 is closer to the substrate 100 than the second planar layer 620. The common electrode 500 is embedded between the first planar layer 610 and the second planar layer 620.

[0048] In the embodiment of the present application, the ultrasonic generating unit 300 includes a piezoelectric material layer 330, which is connected to the first anode 310 and the first cathode 320. The piezoelectric material layer 330 can output ultrasonic waves by inputting a pulse current into the piezoelectric material layer 330. Specifically, a portion of the first anode 310, the piezoelectric material layer 330, and a portion of the first cathode 320 are stacked in sequence in a preset direction. Figure 2 As shown in , the first cathode 320 forms the ultrasonic wave output surface 301 of the ultrasonic wave generating unit 300 , that is, a portion of the first cathode 320 is located at a side of the ultrasonic wave generating unit 300 away from the substrate 100 .

[0049] In the embodiment of the present application, the thermal pressure generating unit 400 includes a thermosensitive material layer 430 and an electrothermal structure 440, the second anode 410 and the second cathode 420 are both electrically connected to the electrothermal structure 440, and the electrothermal structure 440 is connected to the thermosensitive material layer 430. By supplying power to the electrothermal structure 440, the electrothermal structure 440 can output heat, and the heat can cause the thermosensitive material layer 430 to expand and deform in a preset direction, thereby generating a squeezing force on the chip 20, so that the chip 20 abuts against the target substrate 30; at the same time, the heat emitted by the electrothermal structure 440 is also used for bonding the chip 20.

[0050] In order to improve the uniformity of heat output on the hot pressing surface 401 and the uniformity of deformation of the heat-sensitive material layer 430, in this embodiment, the electric heating structure 440 is embedded in the heat-sensitive material layer 430 and extends in a circuitous manner, so that the projection of the electric heating structure 440 on the hot pressing surface 401 has a more uniform distribution. Figure 3 As shown in , the electric heating structure 440 includes a plurality of mutually parallel and spaced substructures, which are sequentially connected in series through the ends to form a circuitous extending electric heating structure 440. Optionally, the electric heating structure 440 is a high impedance thin film metal trace, and the material can be selected from tungsten wire, molybdenum, molybdenum nitride, etc. Optionally, the material of the thermosensitive material layer 430 is selected from a material with a high thermal expansion coefficient, such as organic materials such as polyethylene PE\PVC, polypropylene PP, polycarbonate PC, metal aluminum, Cu60Zn40, FeNi22Cr3, FeNi20Mn6, FeNi13Mn7, Mn72Cr18Ni10 and other alloys. During the transfer process, the electric heating structure 440 is partially covered by the thermosensitive material layer 430, and the thermosensitive material layer 430 expands greatly, lifting the chip 20 from the temporary substrate 10 and abutting against the target substrate 30; part of the heat is transferred to the chip 20 by heat conduction to provide the thermal energy required for bonding.

[0051] In this embodiment, the amount of deformation protrusion that the heat-pressing unit 400 can generate through heat affects the pressure it provides. The amount of deformation protrusion can be determined based on many factors, such as the amount of material to be welded and the amount of solder; at the same time, welding is achieved under the combined action of heat, pressure, and ultrasound, and the pressure required also depends on the heat and ultrasonic energy. Taking multiple aspects into consideration, optionally, the amount of deformation protrusion that the heat-pressing unit 400 can generate through heat is 10 to 500 μm.

[0052] It should be understood that the mass transfer device provided in the embodiment of the present application can be used to transfer Micro LED chips 20 in mass, and can also be used to transfer other types of chips 20.

[0053] Figure 4 This is a flow chart of a method for mass transfer in one embodiment of the present application. Figure 4 As shown, the mass transfer method provided in the embodiment of the present application is implemented using the mass transfer device of the above embodiment of the present application, and the mass transfer method includes the following steps:

[0054] Step S100 , obtaining a temporary substrate 10 carrying a chip 20 , wherein the pins 21 of the chip 20 are facing away from the temporary substrate 10 .

[0055] Figure 5 FIG. 1 is a schematic diagram of a temporary substrate 10 carrying a chip 20 in one embodiment of the present application. Figure 5As shown, in an embodiment of the present application, a temporary substrate 10 can carry a plurality of chips 20, and the plurality of chips 20 are all arranged on the same surface of the temporary substrate 10. The temporary substrate 10 can be made of a blue film or a UV film, and both the UV film and the blue film are sticky. The UV film is a coating applied to the surface of a PET film substrate to achieve the effect of blocking ultraviolet light and short-wavelength visible light. In one embodiment, the UV film has three layers, including a base layer, a sticky layer and a release layer (release film) stacked in sequence, and the base layer is made of polyethylene chloride; in other embodiments, the release layer can also be omitted. The blue film is also called an electronic-grade tape, and its adhesive peeling degree is generally 100 to 3000 mN / 20mm.

[0056] Step S200 , attaching the side of the temporary substrate 10 facing away from the chip 20 to the ultrasonic thermal compression pixel module 101 of the mass transfer device, and making each chip 20 face one ultrasonic thermal compression pixel module 101 in the thickness direction of the temporary substrate 10 .

[0057] Figure 6 This is a schematic diagram of a temporary substrate 10 attached to a mass transfer device in one embodiment of the present application. Figure 6 As shown, there is an ultrasonic hot pressing pixel module 101 directly below each chip 20, and the chip 20 is connected to the hot pressing generating unit 400 of the ultrasonic hot pressing pixel module 101 through a temporary substrate 10; such an arrangement enables the extrusion force, heat and ultrasonic waves provided by the ultrasonic hot pressing pixel module 101 to be better transmitted to the chip 20.

[0058] Step S300 , obtaining a target substrate 30 , aligning the pads 31 on the target substrate 30 with the pins 21 of the chip 20 , and reserving a gap between the pads 31 and the pins 21 .

[0059] In this embodiment, the target substrate 30 is the target to which the chip 20 is to be bonded. Figure 7 FIG. 2 is a schematic diagram of a target substrate 30 before bonding with a chip 20 in one embodiment of the present application. Figure 7 As shown, before the chip 20 is bonded to the target substrate 30, the pad 31 on the target substrate 30 is aligned with the pin 21 of the chip 20, so that when the ultrasonic hot pressing pixel module 101 is subsequently controlled to squeeze the chip 20, the pin 21 of the chip 20 can be accurately fitted with the pad 31. Optionally, the width of the gap reserved between the pad 31 and the pin 21 is 10 to 100 μm. The material of the pad 31 and the pin 21 can be selected from at least one of tin, gold, copper, and indium. In addition, auxiliary materials such as flux can be added to the pad 31 and the pin 21 to assist bonding.

[0060] Step S400, turning on the ultrasonic wave generating unit 300 and the thermal pressure generating unit 400 of at least one ultrasonic thermal pressure pixel module 101, so that under the action of thermal pressure and ultrasound, the pin 21 of the chip 20 abuts against and bonds with the pad 31 to form an electrical connection.

[0061] Figure 8 FIG. 2 is a schematic diagram of a bonding process between a target substrate 30 and a chip 20 in one embodiment of the present application. Figure 8 As shown, when the second thin film transistor switch 220 of the ultrasonic hot pressing pixel module 101 is turned on, the hot pressing generating unit 400 expands and deforms due to the temperature increase, and lifts the temporary substrate 10 and the corresponding chip 20 at the corresponding position, so that the pin 21 of the chip 20 abuts on the pad 31. At the same time, the second thin film transistor switch 220 can be controlled to turn on, so as to apply ultrasonic waves to the chip 20 to help the chip 20 to achieve bonding with the target substrate 30. It can be understood that the temporary substrate 10 has a certain flexibility. When one of the ultrasonic hot pressing pixel modules 101 lifts the corresponding chip 20, the other unactivated ultrasonic hot pressing pixel modules 101 will not lift the temporary substrate 10, and will not cause the chip 20 that does not need to be transferred to contact the pad 31 of the target substrate 30. Therefore, it can be seen that each ultrasonic hot pressing pixel module 101 in the mass transfer device of this embodiment can be independently controlled to selectively transfer the chip 20 on the temporary substrate 10.

[0062] In summary, the embodiment of the present application discloses a mass transfer device and a mass transfer method. The mass transfer device includes a substrate 100 and a plurality of ultrasonic hot pressing pixel modules 101 arranged on the substrate 100; the ultrasonic hot pressing pixel module 101 includes a first thin film transistor switch 210, a second thin film transistor switch 220, an ultrasonic generating unit 300 and a hot pressing generating unit 400, the ultrasonic generating unit 300 is electrically connected to the first thin film transistor switch 210, the hot pressing generating unit 400 is electrically connected to the second thin film transistor switch 220, the first thin film transistor switch 210 is used to control the ultrasonic generating unit 300 to output ultrasonic waves, and the second thin film transistor switch 220 is used to control the hot pressing generating unit 400 to output heat and control the deformation of the hot pressing generating unit 400 in a preset direction. In the embodiment of the present application, the ultrasonic hot pressing pixel module 101 has the functions of hot pressing and ultrasonic processing, and by controlling an ultrasonic hot pressing pixel module 101, a chip 20 can be bonded to a target substrate 30 under the action of hot pressing and ultrasound. Furthermore, the ultrasonic wave generating unit 300 and the heat pressing generating unit 400 can be independently controlled reliably and efficiently through the first thin film transistor switch 210 and the second thin film transistor switch 220 to achieve heat pressing and ultrasonic treatment. Therefore, the mass transfer device and the mass transfer method using the mass transfer device according to the embodiment of the present application can improve the efficiency of mass transfer of the chip 20 and also ensure the yield of mass transfer.

[0063] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed in the present application should be included in the protection scope of the present application.

Claims

1. A mass transfer device, characterized in that: It includes a substrate and a plurality of ultrasonic and hot pressure pixel modules arranged on the substrate; the ultrasonic and hot pressure pixel modules include a first thin film transistor switch, a second thin film transistor switch, an ultrasonic generating unit and a hot pressure generating unit, the ultrasonic generating unit is electrically connected to the first thin film transistor switch, the hot pressure generating unit is electrically connected to the second thin film transistor switch, the first thin film transistor switch is used to control the ultrasonic generating unit to output ultrasonic waves, and the second thin film transistor switch is used to control the hot pressure generating unit to output heat and control the deformation of the hot pressure generating unit in a preset direction.

2. The mass transfer device according to claim 1, characterized in that: The ultrasonic thermal pressure pixel module also includes a common electrode, the ultrasonic wave generating unit includes a first anode and a first cathode, one of the first anode and the first cathode is electrically connected to the first thin-film transistor switch, and the other is electrically connected to the common electrode; the thermal pressure generating unit includes a second anode and a second cathode, one of the second anode and the second cathode is electrically connected to the second thin-film transistor switch, and the other is electrically connected to the common electrode.

3. The mass transfer device according to claim 2, characterized in that: The first thin-film transistor switch includes a first gate, a first source and a first drain, and the second thin-film transistor switch includes a second gate, a second source and a second drain, wherein the first anode is electrically connected to the first drain, the second anode is electrically connected to the second drain, and the first cathode and the second cathode are both electrically connected to the common electrode.

4. The mass transfer device according to claim 2, characterized in that: The ultrasonic wave generating unit includes a piezoelectric material layer, and the piezoelectric material layer is connected to the first anode and the first cathode.

5. The mass transfer device according to claim 4, characterized in that: A portion of the first anode, the piezoelectric material layer, and a portion of the first cathode are stacked in sequence in the preset direction.

6. The mass transfer device according to claim 2, characterized in that: The thermal pressure generating unit comprises a thermosensitive material layer and an electrothermal structure, the second anode and the second cathode are both electrically connected to the electrothermal structure, and the electrothermal structure is connected to the thermosensitive material layer.

7. The mass transfer device according to claim 6, characterized in that: The electric heating structure is embedded in the heat-sensitive material layer and extends in a circuitous manner.

8. The mass transfer device according to claim 2, characterized in that: The mass transfer device includes a flat layer, which is stacked on a side of the first thin-film transistor switch and the second thin-film transistor switch away from the substrate. The ultrasonic generating unit and the hot pressure generating unit are both arranged on a side of the flat layer away from the substrate. The first anode or the first cathode passes through the flat layer and is electrically connected to the first thin-film transistor switch, and the second anode or the second cathode passes through the flat layer and is electrically connected to the second thin-film transistor switch; the common electrode is embedded in the flat layer.

9. The mass transfer device according to claim 1, characterized in that: The ultrasonic generating unit surrounds the outer side of the hot pressing generating unit and forms a closed structure. The side of the ultrasonic generating unit away from the substrate forms an ultrasonic output surface, and the side of the hot pressing generating unit away from the substrate forms a hot pressing surface. The distance between the ultrasonic output surface and the substrate is smaller than the distance between the hot pressing surface and the substrate.

10. A method for mass transfer, characterized in that: Using the mass transfer device according to any one of claims 1 to 9, the mass transfer method comprises: Obtaining a temporary substrate carrying a chip, wherein the pins of the chip face away from the temporary substrate; Attaching a side of the temporary substrate facing away from the chip to the ultrasonic thermal compression pixel module of the mass transfer device, and making each chip face one of the ultrasonic thermal compression pixel modules in the thickness direction of the temporary substrate; Obtain a target substrate, align the pads on the target substrate with the pins of the chip, and reserve a gap between the pads and the pins; The ultrasonic wave generating unit and the thermal pressure generating unit of at least one of the ultrasonic thermal pressure pixel modules are turned on, so that under the action of thermal pressure and ultrasound, the pins of the chip abut against and bond with the pads to form an electrical connection.

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