Light-emitting device, display panel and manufacturing method thereof

Abstract

The invention relates to a light-emitting device which comprises a substrate, a lower-layer chip and an upper-layer LED chip. The lower-layer chip is arranged on the substrate and is electrically connected with a circuit of the substrate through a wiring end of the lower-layer chip; the upper-layer LED chip is arranged on the upper surface of the lower-layer chip, a wiring end of the upper-layer LED chip is suspended on the lower-layer chip, and the upper-layer LED chip is supported on the substrate through a conductive column and is electrically connected with a circuit of the substrate through the conductive column. According to the light-emitting device, the position relation and the electric connection relation of all the assemblies are reasonably arranged, the space position above the substrate in the vertical direction is utilized, and the space utilization rate of the light-emitting device is increased.

Description

Technical Field

[0001] The present invention relates to the technical field of LED packaging, and in particular to a light-emitting device, a display panel and a manufacturing method thereof. Background Art

[0002] As people's visual experience requirements for electronic product displays continue to increase, especially in the field of high-definition display, ultra-high-definition display and even micro-display, the technical development of LED display screens has also ushered in new challenges and opportunities. Improving pixel density has become a breakthrough point to meet these high requirements, and its core lies in increasing the number of LED chips on a unit display panel.

[0003] See also Figure 1 , which is a schematic diagram of the structure of a display panel in the prior art. In the prior art, a plurality of LED chips 2 are arranged in an array on a substrate 1, and the array of LED chips 2 is located on the same plane to form a display panel. Based on this, the prior art further increases the number of LED chips 2 in a single display panel by reducing the dot pitch between the LED chips 2.

[0004] However, in the prior art, the substrate area of ​​the display panel is limited, and the LED chip itself has a certain size. Correspondingly, when the LED chips laid on the surface of the substrate reach the density limit, no more LED chips can be added, and the pixel density cannot be further increased to achieve the effect of ultra-high-definition display. Therefore, the prior art still has the problem of low space utilization for laying the LED chip array on the substrate. Summary of the invention

[0005] Based on this, the object of the present invention is to overcome the defects or shortcomings of the prior art and provide a light emitting device, a display panel and a manufacturing method thereof with high space utilization.

[0006] The light-emitting device described in the present invention includes a substrate; a lower chip, which is arranged on the substrate and is electrically connected to the circuit of the substrate through its wiring terminals; an upper LED chip, which is arranged on the upper surface of the lower chip, and its wiring terminals are suspended from the lower chip and supported on the substrate through conductive columns, and is electrically connected to the circuit of the substrate through the conductive columns.

[0007] The present invention utilizes the upper space position in the vertical direction of the substrate by reasonably arranging the position relationship and electrical connection relationship of each component of the light-emitting device, thereby improving the space utilization rate of the light-emitting device.

[0008] Furthermore, the conductive pillars are inserted on the substrate, which can reduce poor contact caused by stress.

[0009] Furthermore, the lower chip is a control chip or an LED chip.

[0010] Further, the substrate comprises: a first dielectric layer provided with a plurality of first conductive holes;

[0011] A first redistribution layer is disposed on the lower surface of the first dielectric layer and filled in the first conductive hole;

[0012] A second dielectric layer, covering the lower surface of the first dielectric layer and the first redistribution layer, and having a plurality of second conductive holes;

[0013] a second rewiring layer, which is disposed on the lower surface of the second dielectric layer and fills the second conductive hole to be electrically connected to the first rewiring layer;

[0014] The lower chip is arranged on the first dielectric layer of the substrate, and its wiring terminal is electrically connected to the first rewiring layer; the conductive column is inserted into the first dielectric layer and is electrically connected to the first rewiring layer.

[0015] The multi-layer redistribution layer can improve the stability of the light emitting device structure and the stability of the electrical connection.

[0016] Furthermore, the substrate further comprises:

[0017] A third dielectric layer, which covers the lower surface of the second dielectric layer and the second redistribution layer, and is provided with a plurality of third conductive holes;

[0018] A solder ball is filled in the third conductive hole and electrically connected to the second redistribution layer and protrudes from the lower surface of the third dielectric layer.

[0019] Solder balls are provided for easy connection of power supply.

[0020] Furthermore, the upper LED chip is fixed on the lower chip through a transparent adhesive layer. The transparent patch film prevents short circuit inside the light emitting device and tightly fixes the lower chip to the upper LED chip, and also prevents the light emitted by the LED chip from being blocked between the upper and lower chips.

[0021] Furthermore, a method for manufacturing a light emitting device is provided, comprising the steps of:

[0022] Step S10: placing an upper LED chip on the upper surface of the lower chip, and suspending the connection terminal of the upper LED chip above the lower chip;

[0023] Step S20: forming a conductive column on the connection terminal of the upper LED chip;

[0024] Step S30: a substrate is disposed on the lower surface of the lower chip, and the circuits on the substrate are electrically connected to the wiring terminals of the lower chip and to the conductive pillars.

[0025] Furthermore, the step S10 specifically includes:

[0026] Step S11: Arranging the lower chip on the carrier and the glue layer;

[0027] Step S12: placing the upper LED chip on the upper surface of the lower chip so that its wiring terminal is suspended above the lower chip;

[0028] The step S20 specifically includes:

[0029] Step S21: electrically connecting one end of the conductive column to the connection terminal of the upper LED chip, and inserting the other end of the conductive column into the adhesive layer;

[0030] Step S22: removing the carrier board and the adhesive layer to expose the connection terminal of the lower chip; the end of the conductive column protrudes from the lower chip, and the protruding length is D.

[0031] Furthermore, step S30 specifically includes:

[0032] Step S31: placing the semi-finished light-emitting device obtained through steps S10 to S20 upside down, covering the lower chip with a dielectric layer having a thickness greater than D; grinding the dielectric layer until its thickness is the same as the protruding length D of the conductive column; and opening a plurality of first conductive holes on the first dielectric layer;

[0033] Step S32: filling a rewiring layer in the first conductive hole of the first dielectric layer, and forming a first rewiring layer on the surface of the first dielectric layer;

[0034] Step S33: covering the first dielectric layer and the first rewiring layer with a dielectric layer, and opening a plurality of second conductive holes at positions opposite to the first rewiring layer to form a second dielectric layer;

[0035] Step S34: filling the conductive holes of the second dielectric layer with a rewiring layer and forming a second rewiring layer on the surface of the second dielectric layer.

[0036] Furthermore, a display panel is provided, the display panel comprising a substrate and at least one light-emitting module, each light-emitting module comprising:

[0037] A composite stacking unit, comprising a lower control chip disposed on a substrate, which is electrically connected to a circuit of the substrate through its wiring terminals; and an upper first LED chip disposed on the upper surface of the lower control chip, whose wiring terminals are suspended from the lower control chip and supported on the substrate through conductive pillars, and electrically connected to the circuit of the substrate through the conductive pillars;

[0038] Two light-emitting stacking units are respectively arranged on both sides of the composite stacking unit, each light-emitting stacking unit includes a lower second LED chip arranged on the substrate, which is electrically connected to the circuit of the substrate through its wiring terminal; and an upper third LED chip arranged on the upper surface of the lower second LED chip, whose wiring terminal is suspended from the lower second LED chip and supported on the substrate through a conductive column, and is electrically connected to the circuit of the substrate through the conductive column;

[0039] The lower control chip controls the light emission of the upper first LED chip, the lower second LED chip, and the upper third LED chip through the circuit of the substrate.

[0040] Furthermore, the conductive pillar is inserted on the substrate.

[0041] The substrate comprises: a first dielectric layer having a plurality of first conductive holes;

[0042] A first redistribution layer is disposed on the lower surface of the first dielectric layer and filled in the first conductive hole;

[0043] A second dielectric layer, covering the lower surface of the first dielectric layer and the first redistribution layer, and having a plurality of second conductive holes;

[0044] a second rewiring layer, which is disposed on the lower surface of the second dielectric layer and fills the second conductive hole to be electrically connected to the first rewiring layer;

[0045] The lower chip is arranged on the first dielectric layer of the substrate, and its wiring terminal is electrically connected to the first rewiring layer; the conductive column is inserted into the first dielectric layer and is electrically connected to the first rewiring layer.

[0046] The multi-layer redistribution layer can improve the stability of the light emitting device structure and the stability of the electrical connection.

[0047] Furthermore, the substrate further comprises:

[0048] A third dielectric layer, which covers the lower surface of the second dielectric layer and the second redistribution layer, and is provided with a plurality of third conductive holes;

[0049] A solder ball is filled in the third conductive hole and electrically connected to the second redistribution layer and protrudes from the lower surface of the third dielectric layer.

[0050] Solder balls are provided for easy connection of power supply.

[0051] Furthermore, the upper first LED chip is fixed on the lower control chip through a transparent adhesive layer; the upper third LED chip is fixed on the lower second LED chip through a transparent adhesive layer. The transparent patch film prevents short circuits inside the light-emitting device and tightly fixes the lower chip to the upper LED chip, and also prevents the light emitted by the LED chip from being blocked between the upper and lower chips.

[0052] Furthermore, a method for manufacturing a display panel is provided, comprising the steps of:

[0053] Step S10: placing the upper first LED chip and the upper third LED chip on the upper surfaces of the lower control chip and the lower second LED chip respectively, and making the connection terminal of the upper first LED chip suspended on the lower control chip; making the connection terminal of the upper third LED chip suspended on the lower second LED chip;

[0054] Step S20: forming conductive pillars on the connection terminals of the upper first LED chip and the upper third LED chip;

[0055] Step S30: a substrate is arranged on the lower surface of the lower control chip and the lower second LED chip, and the circuit on the substrate is electrically connected to the wiring terminal of the lower chip and to the conductive column.

[0056] Furthermore, the step S10 specifically includes:

[0057] Step S11: arranging a lower layer control chip at the center of the carrier board and the adhesive layer, and arranging lower layer second LED chips on both sides of the lower layer control chip;

[0058] Step S12: Set the transparent adhesive layer on the lower control chip and the lower second LED chip respectively, and then set the upper first LED chip and the upper third LED chip on the upper surface of the lower control chip and the lower second LED chip respectively, and make the connection terminal of the upper first LED chip suspended on the lower control chip; make the connection terminal of the upper third LED chip suspended on the lower second LED chip.

[0059] The step S20 specifically includes:

[0060] Step S21: electrically connecting one end of the conductive column to the connection terminals of the upper first LED chip and the upper third LED chip, and inserting the other end of the conductive column into the adhesive layer;

[0061] Step S22: removing the carrier board and the adhesive layer to expose the connection terminals of the lower control chip and the lower second LED chip; the end of the conductive column protrudes from the lower chip, and the protruding length is D.

[0062] Furthermore, step S30 specifically includes:

[0063] Step S31: placing the semi-finished display panel obtained through steps S10 to S20 upside down, covering the lower control chip and the lower second LED chip with a dielectric layer having a thickness greater than D; grinding the dielectric layer until its thickness is the same as the protruding length D of the conductive column; and opening a plurality of first conductive holes on the first dielectric layer;

[0064] Step S32: filling a rewiring layer in the first conductive hole of the first dielectric layer, and forming a first rewiring layer on the surface of the first dielectric layer;

[0065] Step S33: covering the first dielectric layer and the first rewiring layer with a dielectric layer, and opening a plurality of second conductive holes at positions opposite to the first rewiring layer to form a second dielectric layer;

[0066] Step S34: filling the conductive holes of the second dielectric layer with a rewiring layer and forming a second rewiring layer on the surface of the second dielectric layer.

[0067] For better understanding and implementation, the present invention is described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0068] Figure 1 It is a schematic diagram of the structure of a display panel in the prior art;

[0069] Figure 2 This is a schematic structural diagram of a light emitting device according to Embodiment 1 of the present invention;

[0070] Figure 3 It is a schematic structural diagram of a light emitting device provided with solder balls according to the present invention;

[0071] Figure 4 This is a schematic diagram of step S10 of the method for manufacturing a light emitting device according to embodiment 2 of the present invention;

[0072] Figure 5 This is a schematic diagram of step S20 of the method for manufacturing a light emitting device according to embodiment 2 of the present invention;

[0073] Figure 6 This is a schematic diagram of step S30 of the method for manufacturing a light emitting device according to embodiment 2 of the present invention;

[0074] Figure 7 This is a schematic diagram of step S41 of the method for manufacturing a light emitting device according to embodiment 2 of the present invention;

[0075] Figure 8 This is a schematic diagram of step S42 of the method for manufacturing a light emitting device according to embodiment 2 of the present invention;

[0076] Fig. 9 This is a schematic diagram of step S43 of the method for manufacturing a light emitting device according to embodiment 2 of the present invention;

[0077] Fig.10 This is a schematic diagram of step S44 of the method for manufacturing a light emitting device according to embodiment 2 of the present invention;

[0078] Fig.11 It is a schematic diagram of steps S45 and S46 of the method for manufacturing a light emitting device according to embodiment 2 of the present invention;

[0079] Fig.12 It is a schematic structural diagram of the light emitting device according to Embodiment 2 of the present invention.

[0080] Description of the drawings: substrate 1, LED chip 2; substrate 10, first dielectric layer 11, first redistribution layer 12, second dielectric layer 13, second redistribution layer 14, third dielectric layer 15, solder balls 16, lower chip 20, lower control chip 21, lower second LED chip 22, upper LED chip 30, connection terminal 31, upper first LED chip 32, upper third LED chip 34, transparent adhesive layer 40, conductive column 50, plastic encapsulation layer 60, carrier 70, glue layer 80. DETAILED DESCRIPTION

[0081] In order to solve the problem of low space utilization when laying an LED chip array on a substrate, the present invention utilizes the upper space in the vertical direction of the substrate by reasonably arranging the position relationship and electrical connection relationship of each component, thereby improving the space utilization of the light-emitting device. The present invention is described in detail below in conjunction with specific embodiments.

[0082] Example 1

[0083] See also Figure 2, which is a schematic diagram of the structure of the light-emitting device of Embodiment 1 of the present invention. The light-emitting device of the present invention comprises a substrate 10, a lower chip 20, an upper LED chip 30, a transparent adhesive layer 40, a conductive column 50 and a plastic encapsulation layer 60. The lower chip 20 is arranged on the substrate 10, and is electrically connected to the circuit of the substrate 10 through the wiring terminal (not shown) of the lower chip 20; the upper LED chip 30 is fixed to the upper surface of the lower chip 20 through the transparent adhesive layer 40, and the wiring terminal 31 of the upper LED chip 30 is suspended from the lower chip 20, supported on the substrate 10 through the conductive column 50, and is electrically connected to the circuit of the substrate 10 through the conductive column 50. The plastic encapsulation layer 60 is arranged on the substrate 10, covering the lower chip 20, the upper LED chip 30 and the conductive column 50.

[0084] Specifically, the lower chip 20 is a control chip or an LED chip. This embodiment takes the control chip as an example of the lower chip to illustrate the implementation of the present invention.

[0085] The control chip is electrically connected to the upper LED chip 30 through the substrate 10 and the conductive column 50, and controls and drives the upper LED chip 30 to emit light. The control chip is embedded with a solder pad at its terminal, and preferably, the bottom surface of the solder pad is flush with the bottom surface of the control chip body; the side of the control chip with the solder pad is attached to the substrate 10, and the control chip is specifically a bare crystal IC chip.

[0086] The upper LED chip 30 is provided with a plurality of pads electrically connected to the conductive pillars 50 at the connection terminals 31. The area of ​​overlap between the control chip and the orthographic projection of the upper LED chip 30 is 2 / 3 to 5 / 6 of the orthographic projection area of ​​the upper LED chip 30. The chip type of the upper LED chip 30 is preferably a flip chip. It can be understood that generally, there are two electrodes at the bottom of the LED flip chip, and the number of conductive pillars 50 corresponding to each upper LED chip 30 should be two.

[0087] The material of the transparent adhesive layer 40 is a transparent PET film (polyethylene terephthalate film), which has good electrical insulation and mechanical properties, can avoid internal short circuits in the light-emitting device and tightly fix the lower chip 20 and the upper LED chip 30, and can also prevent the light emitted by the LED chip from being blocked between the upper and lower chips.

[0088] The conductive pillar 50 is inserted on the substrate 10, and the insertion depth D is set to 5-10 μm; the diameter of the conductive pillar 50 is set to 8-12 μm to reduce the poor contact caused by stress. The conductive pillar 50 is formed by electroplating on the pad, and the material of the conductive pillar 50 can be one or more of copper, nickel, zinc, tin, silver, gold, tungsten and magnesium.

[0089] The plastic packaging layer 60 protects the control chip, the upper LED chip 30 and the conductive column 50 , and the material thereof can be epoxy resin.

[0090] The substrate 10 includes a first dielectric layer 11, a first rewiring layer 12, a second dielectric layer 13 and a second rewiring layer 14. The first dielectric layer 11 and the second dielectric layer 13 are insulating; the first rewiring layer 12 and the second rewiring layer 14 are conductive.

[0091] A plurality of first conductive holes are provided on the first dielectric layer 11. Specifically, the control chip is provided on the first dielectric layer 11, and the side of the control chip provided with the pad faces the first dielectric layer 11; the first conductive holes are respectively provided at the pad of the control chip and the orthographic projection position of the conductive column 50 on the first dielectric layer 11, and the conductive column 50 is inserted into the first conductive hole facing it.

[0092] The first redistribution layer 12 is disposed on the lower surface of the first dielectric layer 11 and is filled in the first conductive hole, and is electrically connected to the control chip and the conductive pillar 50 by contacting each other.

[0093] The second dielectric layer 13 covers the lower surface of the first dielectric layer 11 and the first rewiring layer 12 to protect the first rewiring layer 12. The second dielectric layer 13 is also provided with a plurality of second conductive holes opposite to the first rewiring layer 12.

[0094] The second rewiring layer 14 is disposed on the lower surface of the second dielectric layer and fills the second conductive hole to be electrically connected to the first rewiring layer 12. The surface of the second rewiring layer 14 is exposed to facilitate electrical connection with a power source. The control chip is electrically connected to the upper LED chip 30 and an external power source through the first rewiring layer 12 and the second rewiring layer 14.

[0095] The arrangement of the above-mentioned multi-layer dielectric layer and the rewiring layer is conducive to increasing the stability of the structure of the substrate 10, and preventing the delamination between the rewiring layer and the dielectric layer, which leads to poor contact of the light-emitting device circuit. Preferably, the first dielectric layer 11 and the second dielectric layer 13 are made of insulating materials such as polyimide and polybenzoxazole. Compared with the commonly used ceramic substrate, the substrate of the present invention is thinner and has lower cost.

[0096] As a further optimization of the above solution, please refer to Figure 3 , the substrate 10 further includes a third dielectric layer 15 and solder balls 16. The third dielectric layer 15 covers the lower surface of the second dielectric layer 13 and the second rewiring layer 14 to protect the second rewiring layer 14. The third dielectric layer 15 is also provided with a plurality of third conductive holes opposite to the second rewiring layer 14. The solder balls 16 are filled in the third conductive holes and electrically connected to the second rewiring layer 14, and protrude from the lower surface of the third dielectric layer 15 so as to be electrically connected to an external power source. The third dielectric layer 15 and the solder balls 16 can improve the support force of the substrate 10 for other components, prevent the substrate 10 from bending and deforming, and further enhance the stability of the structure of the substrate 10.

[0097] Compared with the prior art, the present invention improves the space utilization rate of the light-emitting device by rationally arranging the positional relationship and electrical connection relationship of the components of the light-emitting device to utilize the upper space position in the vertical direction of the substrate; ensures the stability of the light-emitting device structure and the stability of the electrical connection by setting multiple layers of redistribution layers; further sets solder balls to facilitate the connection of the power supply; avoids internal short circuit of the light-emitting device and tightly fixes the lower chip and the upper LED chip by setting a transparent patch film, and also prevents the light emitted by the LED chip from being blocked between the upper and lower chips.

[0098] The following is an example of manufacturing the light-emitting device of Embodiment 1 of the present invention to introduce the method for manufacturing the light-emitting device of the present invention, which includes the following steps:

[0099] Step S10: placing the upper LED chip 30 on the upper surface of the lower chip 20, and making the connection terminal 31 of the upper LED chip 30 suspended on the lower chip 20;

[0100] Step S20: forming a conductive column 50 on the connection terminal 31 of the upper LED chip;

[0101] Step S30 : disposing a substrate 10 on the lower surface of the lower chip 20 , and electrically connecting the circuits on the substrate 10 to the terminals 31 of the lower chip 20 and to the conductive pillars 50 .

[0102] The step S10 specifically includes:

[0103] Step S11: Arrange the lower chip 20 on the carrier 70 and the adhesive layer 80. Figure 4, the side of the control chip with the pad is attached to the carrier 70 provided with the adhesive layer 80. The adhesive layer 80 can be a temporary bonding adhesive, and the material can be a sticky dry film or a die-bonding film, which can achieve the adhesive bonding of the LED chip, and the adhesive layer 80 can be removed later by the existing removal method; the carrier 70 has the function of carrying the chip, and its material can be glass, silicon or metal.

[0104] Step S12: placing the upper LED chip 30 on the lower chip 20. Specifically, placing the transparent adhesive layer 40 on the lower chip 20, and then placing the upper LED chip 30 on the upper surface of the lower chip 20, with its terminal 31 suspended from the lower chip 20.

[0105] The step S20 specifically includes:

[0106] Step S21: Please refer to Figure 5 , connect one end of the conductive column 50 to the pad of the terminal 31, and insert the other end of the conductive column 50 into the glue layer 80, the insertion depth D is less than the thickness of the glue layer 80, and the depth D is preferably 5 to 10 μm, so that the conductive column 50 can be subsequently inserted into the first conductive hole of the dielectric layer 11 and electrically connected to the redistribution layer 12; a plastic encapsulation layer 60 is arranged on the glue layer 80, and the plastic encapsulation layer 60 wraps the lower chip 20, the upper LED chip 30 and the conductive column 50.

[0107] Step S22: Please refer to Figure 6 , remove the carrier and the glue layer, so that the pad of the lower chip 20 is exposed on the surface of the plastic layer and is flush with the bottom surface of the plastic layer 60; the end of the conductive column 50 protrudes from the lower chip 20, and the protruding length is D. The method of removing the carrier and the glue layer can be selected from one or more of thermal separation, laser separation, ultraviolet separation, and mechanical separation.

[0108] The step S30 specifically includes:

[0109] Step S31: forming the first dielectric layer 11 on the side of the control chip where the pad is provided. Figure 7, the semi-finished light-emitting device obtained through step S10 to step S20 is placed upside down, and a dielectric layer with a thickness greater than D is covered on the side of the control chip with the pad. The dielectric layer is ground until its thickness is the same as the protruding length D of the conductive column 50, and the end face of the conductive column 50 is exposed; a plurality of first conductive holes are opened at the positive projection position of the first dielectric layer 11 of the pad and the conductive column of the lower chip 20. The material of the first dielectric layer 11 is polyimide, polybenzoxazole, etc., and the dielectric layer is formed by chemical vapor deposition or physical vapor deposition process, and the dielectric layer is further patterned by photolithography process. The first conductive hole can be opened in the dielectric layer by photolithography etching.

[0110] Step S32: forming a first redistribution layer 12 on the first dielectric layer 11. Figure 8 , filling the first conductive hole of the first dielectric layer 11 with a rewiring layer, and forming a first rewiring layer 12 on the surface of the first dielectric layer 11 .

[0111] Step S33: forming a second dielectric layer 13 on the first dielectric layer 11 and the first redistribution layer 12. Fig. 9 A dielectric layer is covered on the first dielectric layer 11 and the first rewiring layer 12, and a plurality of second conductive holes are opened at positions opposite to the first rewiring layer 12 to form a second dielectric layer 13. The second dielectric layer 13 has the same material, manufacturing process and conductive hole opening method as the first dielectric layer 11.

[0112] Step S34: forming a second redistribution layer 14 on the second dielectric layer 13. Fig.10 , filling the second conductive hole of the second dielectric layer 13 with a rewiring layer and forming a second rewiring layer 14 on the surface of the second dielectric layer 13. The second rewiring layer 14 is electrically connected to the first rewiring layer 12 through the second conductive hole.

[0113] See also Fig.11 , the method for manufacturing a light emitting device provided with a third dielectric layer 15 and a solder ball 16 further includes:

[0114] Step S35: forming the third dielectric layer 15 on the second dielectric layer 13 and the second rewiring layer 14. Specifically, a dielectric layer is covered on the second dielectric layer 13 and the second rewiring layer 14, and a plurality of third conductive holes are opened at positions opposite to the second rewiring layer 14 to form the third dielectric layer 15. The third dielectric layer 15 has the same material, manufacturing process and conductive hole opening method as the first dielectric layer 11.

[0115] Step S36: Fill the third conductive hole of the third dielectric layer 15 with a solder ball 16 and electrically connect the solder ball to the second redistribution layer 14, and the solder ball protrudes from the third dielectric layer 15. The solder ball 16 is formed by electroplating or sintering.

[0116] Compared with the prior art, the light-emitting device manufacturing method of the present invention first sets the lower chip, upper LED chip, conductive column and other structures above the substrate, and then sets the substrate on the lower chip, which is conducive to accurately arranging the position of the conductive column and has the advantages of simple and precise operation and low cost.

[0117] Example 2

[0118] In the prior art, in order to achieve rich display effects, three LED chips, namely, a red light chip, a green light chip, and a blue light chip, are usually used as a pixel group, with a total of n groups (n is a positive integer), and then a single or multiple control chips and the n pixel groups are laid flat on a substrate to form a display panel. The control chip controls the light emission of LED chips of different colors to obtain a variety of light emission combinations. However, the prior art requires at least 3n LED chips to meet the required display effects, but a large number of LED chips will result in a larger volume of the light-emitting device obtained by packaging.

[0119] Regarding the problem that the LED chips in the prior art are too many and thus the light emitting device is too large, please refer to Fig.12 This embodiment forms a display panel with a smaller packaging volume based on the first embodiment.

[0120] Specifically, the display panel of this embodiment includes a substrate 10 and at least one light-emitting module. The substrate 10 has the same structure as the substrate in Example 1 and is not repeated here. Each light-emitting module includes a composite stacking unit and two light-emitting stacking units respectively arranged on both sides of the composite stacking unit.

[0121] When the lower chip 20 of the light-emitting device in Example 1 is a control chip, the control chip and the upper LED chip 30 and the conductive column 50 form a composite stacking unit of this embodiment; when the lower chip 20 of the light-emitting device in Example 1 is an LED chip, the LED chip and the upper LED chip 30 and the conductive column 50 form a light-emitting stacking unit of this embodiment.

[0122] Specifically, the composite stacking unit includes a lower control chip 21 arranged at the center position of the substrate 10, an upper first LED chip 32 and a conductive column 50 arranged on the upper surface of the lower control chip 21; the lower control chip 21 is electrically connected to the circuit of the substrate 10 through its wiring terminal; the wiring terminal of the upper first LED chip 32 is suspended from the lower control chip 21, and is supported on the substrate 10 through the conductive column 50, and is electrically connected to the circuit of the substrate 10 through the conductive column 50.

[0123] Each light-emitting stacking unit includes a lower second LED chip 22 arranged on a substrate, an upper third LED chip 34 arranged on the upper surface of the lower second LED chip 22, and a conductive column 50; the lower second LED chip 22 is electrically connected to the circuit of the substrate through its terminal; the terminal of the upper third LED chip 34 is suspended above the lower second LED chip 22, and is supported on the substrate 10 through the conductive column 50, and is electrically connected to the circuit of the substrate 10 through the conductive column 50.

[0124] Each of the upper first LED chip 32 , the lower second LED chip 22 , and the upper third LED chip 34 is connected in parallel via the substrate 10 , and the lower control chip 21 controls each LED chip to emit light individually.

[0125] The same transparent adhesive layer 40 as in Example 1 is provided between the lower control chip 21 and the upper first LED chip 32, and between the lower second LED chip 22 and the upper third LED chip 34. The transparent adhesive layer 40 has a transparent property, and can reduce the light blocking of the upper third LED chip 34 to the lower second LED chip 22. Further, the same plastic sealing layer 60 as in Example 1 is provided, and the plastic sealing layer 60 is provided on the substrate 10, and the plastic sealing layer 60 wraps the light-emitting module to protect the light-emitting module, and the material thereof can be epoxy resin.

[0126] In this embodiment, the second LED chip 22 of the lower layer is a red chip; the first LED chip 32 of the upper layer is a blue chip, and the third LED chip 34 of the upper layer is a green chip. Accordingly, the red chip and the green chip of each light-emitting stacking unit can be used as a group of pixel groups together with the blue chip of the composite stacking unit; that is, the two light-emitting stacking units arranged on both sides of the composite stacking unit form two groups of pixel groups by sharing a blue chip. In addition, the second LED chip 22 of the lower layer, the first LED chip 32 of the upper layer, and the third LED chip 34 of the upper layer can be any one of a red chip, a green chip, and a blue chip, respectively, and finally combined to form a group of pixel groups.

[0127] The lower-level control chip 21 is preset with algorithms such as pixel multiplexing and color rendering. It utilizes the blue light chip shared by the two pixel groups and the visual residual effect of the human eye to accurately drive and control the lighting sequence and duration of each LED chip to form multiple virtual pixels, thereby increasing the pixel density and displaying more image details and effects.

[0128] Compared with the prior art, the display panel of the present invention fully utilizes the space above the substrate through the composite stacking unit and the light-emitting stacking unit, so that the space utilization rate of the display panel is higher; and a smaller number of LED chips are used to achieve the effect of increasing the visual pixel density, forming a display panel with a smaller package volume. In addition, since this embodiment uses fewer LED chips, the heat accumulation of the display panel is reduced, and the heat dissipation effect is better.

[0129] The display panel of the present application is formed on the basis of the light-emitting device of Example 1. Accordingly, the manufacturing method of the display panel of the present application is substantially the same as the manufacturing method of the light-emitting device of Example 1, except that:

[0130] In this embodiment, the lower chip 20 includes a lower control chip 21 and a lower second LED chip 22 ; the upper LED chip 30 includes an upper first LED chip 32 and an upper third LED chip 34 .

[0131] Step S10: The upper first LED chip 32 and the upper third LED chip 34 are respectively arranged on the upper surfaces of the lower control chip 21 and the lower second LED chip 22, and the connection terminal of the upper first LED chip 32 is suspended on the lower control chip 21; the connection terminal of the upper third LED chip 34 is suspended on the lower second LED chip 22;

[0132] The step S10 specifically includes:

[0133] Step S11: Arrange the lower control chip 21 at the center of the carrier 70 and the adhesive layer 80, and arrange the lower second LED chip 22 on both sides of the lower control chip 21. Specifically, the lower control chip 21 and the lower second LED chip 22 are adhered to the carrier 70 provided with the adhesive layer 80 on one side thereof provided with the solder pads.

[0134] Step S12: The transparent adhesive layer 40 is respectively arranged on the lower control chip 21 and the lower second LED chip 22, and then the upper first LED chip 32 and the upper third LED chip 34 are respectively arranged on the upper surface of the lower control chip 21 and the lower second LED chip 22, and the connection terminal of the upper first LED chip 32 is suspended on the lower control chip 21; the connection terminal of the upper third LED chip 34 is suspended on the lower second LED chip 22.

[0135] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the embodiments of the present application. The terms "first", "second", "third", etc. are only used to distinguish, rather than to describe a specific order or sequence, and cannot be understood as indicating or implying relative importance. In the description of the present application, for those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0136] The above-mentioned embodiments only express several implementation methods of the present invention, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the invention patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, and the present invention is also intended to include these modifications and modifications.

Claims

1. A light emitting device, characterized in that: include substrate; A lower chip, which is arranged on the substrate and electrically connected to the circuit of the substrate through its wiring terminals; The upper LED chip is arranged on the upper surface of the lower chip, and its connection terminal is suspended from the lower chip and supported on the substrate through conductive pillars, and is electrically connected to the circuit of the substrate through the conductive pillars.

2. The light emitting device according to claim 1, characterized in that: The conductive pillar is inserted on the substrate.

3. The light emitting device according to claim 1, characterized in that: The lower chip is a control chip or an LED chip.

4. The light emitting device according to any one of claims 1 to 3, characterized in that: The substrate comprises: The first dielectric layer is provided with a plurality of first conductive holes; A first redistribution layer is disposed on the lower surface of the first dielectric layer and filled in the first conductive hole; A second dielectric layer, covering the lower surface of the first dielectric layer and the first redistribution layer, and having a plurality of second conductive holes; a second rewiring layer, which is disposed on the lower surface of the second dielectric layer and fills the second conductive hole to be electrically connected to the first rewiring layer; The lower chip is arranged on the first dielectric layer of the substrate, and its wiring terminal is electrically connected to the first rewiring layer; the conductive column is inserted into the first dielectric layer and is electrically connected to the first rewiring layer.

5. The light emitting device according to claim 4, characterized in that: The substrate further comprises: A third dielectric layer, which covers the lower surface of the second dielectric layer and the second redistribution layer, and is provided with a plurality of third conductive holes; A solder ball is filled in the third conductive hole and electrically connected to the second redistribution layer and protrudes from the lower surface of the third dielectric layer.

6. The light emitting device according to claim 4, characterized in that: The upper LED chip is fixed on the lower chip via a transparent adhesive layer.

7. A method for manufacturing a light emitting device, characterized in that: Includes steps: Step S10: placing an upper LED chip on the upper surface of the lower chip, and suspending the connection terminal of the upper LED chip above the lower chip; Step S20: forming a conductive column on the connection terminal of the upper LED chip; Step S30: a substrate is disposed on the lower surface of the lower chip, and the circuits on the substrate are electrically connected to the wiring terminals of the lower chip and to the conductive pillars.

8. The method for manufacturing a light emitting device according to claim 7, characterized in that: The step S10 specifically includes: Step S11: Arranging the lower chip on the carrier and the glue layer; Step S12: placing the upper LED chip on the upper surface of the lower chip so that its wiring terminal is suspended above the lower chip; The step S20 specifically includes: Step S21: electrically connecting one end of the conductive column to the connection terminal of the upper LED chip, and inserting the other end of the conductive column into the adhesive layer; Step S22: removing the carrier board and the adhesive layer to expose the connection terminal of the lower chip; the end of the conductive column protrudes from the lower chip, and the protruding length is D.

9. The method for manufacturing a light emitting device according to claim 8, characterized in that: Step S30 specifically includes: Step S31: placing the semi-finished light-emitting device obtained through steps S10 to S20 upside down, covering the lower chip with a dielectric layer having a thickness greater than D; grinding the dielectric layer until its thickness is the same as the protruding length D of the conductive column; and opening a plurality of first conductive holes on the first dielectric layer; Step S32: filling a rewiring layer in the first conductive hole of the first dielectric layer, and forming a first rewiring layer on the surface of the first dielectric layer; Step S33: covering the first dielectric layer and the first rewiring layer with a dielectric layer, and opening a plurality of second conductive holes at positions opposite to the first rewiring layer to form a second dielectric layer; Step S34: filling the conductive holes of the second dielectric layer with a rewiring layer and forming a second rewiring layer on the surface of the second dielectric layer.

10. A display panel comprising a substrate and at least one light-emitting module, characterized in that: Each light-emitting module includes: A composite stacking unit, comprising a lower control chip disposed on a substrate, which is electrically connected to a circuit of the substrate through its wiring terminals; and an upper first LED chip disposed on the upper surface of the lower control chip, whose wiring terminals are suspended from the lower control chip and supported on the substrate through conductive pillars, and electrically connected to the circuit of the substrate through the conductive pillars; Two light-emitting stacking units are respectively arranged on both sides of the composite stacking unit, each light-emitting stacking unit includes a lower second LED chip arranged on the substrate, which is electrically connected to the circuit of the substrate through its wiring terminal; and an upper third LED chip arranged on the upper surface of the lower second LED chip, whose wiring terminal is suspended from the lower second LED chip and supported on the substrate through a conductive column, and is electrically connected to the circuit of the substrate through the conductive column; The lower control chip controls the light emission of the upper first LED chip, the lower second LED chip, and the upper third LED chip through the circuit of the substrate.

11. The display panel according to claim 10, characterized in that: The conductive pillar is inserted on the substrate.

12. The display panel according to claim 11, characterized in that: The upper first LED chip is fixed on the lower control chip through a transparent adhesive layer; the upper third LED chip is fixed on the lower second LED chip through a transparent adhesive layer.

13. A method for manufacturing a display panel, characterized in that: Includes steps: Step S10: placing the upper first LED chip and the upper third LED chip on the upper surfaces of the lower control chip and the lower second LED chip respectively, and making the connection terminal of the upper first LED chip suspended on the lower control chip; making the connection terminal of the upper third LED chip suspended on the lower second LED chip; Step S20: forming conductive pillars on the connection terminals of the upper first LED chip and the upper third LED chip; Step S30: a substrate is arranged on the lower surface of the lower control chip and the lower second LED chip, and the circuit on the substrate is electrically connected to the wiring terminal of the lower chip and to the conductive column.

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