Full-color LED structure and preparation method thereof

Abstract

The invention discloses a full-color LED structure and a preparation method thereof. The full-color LED structure comprises a first substrate; the first color light-emitting unit and the second color light-emitting unit are arranged on one side of the first substrate, are arranged on the same layer and are prepared at the same time; the third-color light-emitting unit is arranged on the sides, away from the first substrate, of the first-color light-emitting unit and the second-color light-emitting unit, and the vertical projection of the third-color light-emitting unit on the first substrate is not overlapped with the vertical projection of the first-color light-emitting unit and the second-color light-emitting unit on the first substrate. Full-color display can be realized, and the luminous efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to a full-color LED structure and a preparation method thereof. Background Art

[0002] In the prior art, the methods for achieving full colorization are divided into full-color epitaxy, mass transfer, three-color light combination and color conversion, etc. However, in the full-color epitaxy method, the luminous efficiency of the device that directly realizes the three-color light-emitting diode by epitaxy is low; in the mass transfer method, the single-color light-emitting diodes are separately manufactured and then transferred, the transfer efficiency is low, and the transfer yield is limited; in the three-color light combination method, the red light device has a size effect and a low luminous efficiency; in the color conversion method, the photoresist organic material will have the problem of wavelength conversion resulting in reduced luminous efficiency. Summary of the invention

[0003] The invention provides a full-color LED structure and a preparation method thereof, which can realize full color and improve the luminous efficiency of the device.

[0004] According to one aspect of the present invention, a full-color LED structure is provided, comprising:

[0005] a first substrate;

[0006] A first color light-emitting unit and a second color light-emitting unit are arranged on one side of the first substrate, and the first color light-emitting unit and the second color light-emitting unit are arranged in the same layer and prepared at the same time;

[0007] A third color light emitting unit is arranged on a side of the first color light emitting unit and the second color light emitting unit away from the first substrate, and a vertical projection of the third color light emitting unit on the first substrate does not overlap with a vertical projection of the first color light emitting unit and the second color light emitting unit on the first substrate.

[0008] According to another aspect of the present invention, there is provided a method for preparing a full-color LED structure, comprising:

[0009] A first color light-emitting unit and a second color light-emitting unit are simultaneously prepared on one side of the first substrate, and the first color light-emitting unit and the second color light-emitting unit are arranged in the same layer;

[0010] preparing a third color material layer on one side of the second substrate;

[0011] Combining the first substrate and the second substrate so that the first color light emitting unit, the second color light emitting unit and the third color material layer are located between the first substrate and the second substrate;

[0012] removing the second substrate;

[0013] A dividing groove is made, which at least penetrates the third color material layer to form multiple third color sub-layers, wherein the third color sub-layer whose vertical projection on the first substrate does not overlap with the vertical projection of the first color light-emitting unit and the second color light-emitting unit on the first substrate is a third color light-emitting unit.

[0014] According to another aspect of the present invention, there is provided a method for preparing a full-color LED structure, comprising:

[0015] A first color light-emitting unit and a second color light-emitting unit are simultaneously prepared on one side of the first substrate, and the first color light-emitting unit and the second color light-emitting unit are arranged in the same layer;

[0016] Preparing a third color light-emitting unit on one side of the second substrate;

[0017] Combine the first substrate and the second substrate so that the first color light emitting unit, the second color light emitting unit and the third color light emitting unit are located between the first substrate and the second substrate, and the vertical projection of the third color light emitting unit on the first substrate does not overlap with the vertical projection of the first color light emitting unit and the second color light emitting unit on the first substrate;

[0018] The second substrate is removed.

[0019] The full-color LED structure provided by the technical solution of the embodiment of the present invention includes: a first substrate; a first color light-emitting unit and a second color light-emitting unit arranged on one side of the first substrate, the first color light-emitting unit and the second color light-emitting unit are arranged in the same layer and are prepared at the same time; a third color light-emitting unit is arranged on the side of the first color light-emitting unit and the second color light-emitting unit away from the first substrate, and the vertical projection of the third color light-emitting unit on the first substrate does not overlap with the vertical projection of the first color light-emitting unit and the second color light-emitting unit on the first substrate, so that the first color light-emitting unit, the second color light-emitting unit and the third color light-emitting unit are independent of each other, and the emitted light does not overlap with each other and is less blocked, so the color brightness is higher, so full-color display can be achieved and the luminous efficiency is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0021] Figure 1 is a schematic diagram of a full-color LED structure provided by Embodiment 1 of the present invention;

[0022] Figure 2is a schematic diagram of another full-color LED structure provided by the first embodiment of the present invention;

[0023] Figure 3 This is another arrangement diagram of light-emitting units provided in the first embodiment of the present invention;

[0024] Figure 4 This is another arrangement diagram of light-emitting units provided in the first embodiment of the present invention;

[0025] Figure 5 This is another arrangement diagram of light-emitting units provided in the first embodiment of the present invention;

[0026] Figure 6 This is another arrangement diagram of light-emitting units provided in the first embodiment of the present invention;

[0027] Figure 7 This is another arrangement diagram of light-emitting units provided in the first embodiment of the present invention;

[0028] Figure 8 is a schematic diagram of another full-color LED structure provided by the first embodiment of the present invention;

[0029] Fig. 9 is a flow chart of a method for preparing a full-color LED structure provided in Embodiment 2 of the present invention;

[0030] Figures 10 to 13 This is a schematic diagram of an intermediate structure of a full-color LED structure provided by Embodiment 2 of the present invention;

[0031] Fig.14 yes Fig. 9 A detailed flowchart of step 300;

[0032] Figures 15 to 17 This is a schematic diagram of an intermediate structure of a full-color LED structure provided by Embodiment 2 of the present invention;

[0033] Fig.18 yes Fig.14 A detailed flowchart of step 310;

[0034] Figures 19 to 23 This is a schematic diagram of an intermediate structure of a full-color LED structure provided by Embodiment 2 of the present invention;

[0035] Figure 24 to Figure 25 This is a schematic diagram of an intermediate structure of a full-color LED structure provided by Embodiment 2 of the present invention;

[0036] Fig.26 is a flow chart of a method for preparing a full-color LED structure provided in Embodiment 3 of the present invention;

[0037] Fig. 27is a schematic diagram of a full-color LED structure provided by Embodiment 3 of the present invention;

[0038] Fig.28 It is a schematic diagram of a full-color LED structure provided in Embodiment 3 of the present invention. DETAILED DESCRIPTION

[0039] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0040] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0041] Embodiment 1

[0042] The embodiment of the present invention provides a full-color LED structure. Figure 1 is a structural schematic diagram of a full-color LED structure provided by Embodiment 1 of the present invention, Figure 2 is a structural schematic diagram of another full-color LED structure provided in the first embodiment of the present invention, referring to Figure 1 and Figure 2 , full-color LED structure includes:

[0043] A first substrate 01; a first color light-emitting unit 03 and a second color light-emitting unit 04 arranged on one side of the first substrate 01, the first color light-emitting unit 03 and the second color light-emitting unit 04 being arranged on the same layer and being prepared at the same time; a third color light-emitting unit 06 arranged on a side of the first color light-emitting unit 03 and the second color light-emitting unit 04 away from the first substrate 01, the vertical projection of the third color light-emitting unit 06 on the first substrate 01 not overlapping with the vertical projection of the first color light-emitting unit 03 and the second color light-emitting unit 04 on the first substrate 01.

[0044] The material of the first substrate 01 may be silicon, sapphire or the like; optionally, the material of the first substrate 01 is a transparent material. The three-dimensional shape of the first color light-emitting unit 03 may be a hexagonal pyramid, a hexagonal pyramid or a tetrahedron. The first color light-emitting unit 03 and the second color light-emitting unit 04 may be grown simultaneously on one side of the first substrate 01, and the first color light-emitting unit 03 and the second color light-emitting unit 04 may be prepared simultaneously by controlling the duty cycle of the window by adopting a selective epitaxial growth method, thereby simplifying the process steps.

[0045] Specifically, Figure 1 As shown, if the shape of the first color light-emitting unit 03 is a hexagonal pyramid and the shape of the second color light-emitting unit 04 is a tetrahedron, the height of the first color light-emitting unit 03 is greater than the height of the second color light-emitting unit 04, that is, the first color light-emitting unit 03 and the second color light-emitting unit 04 are in the same layer but have different heights. If the shape of the first color light-emitting unit 03 and the second color light-emitting unit 04 are both tetrahedrons, the height of the first color light-emitting unit 03 is the same as the height of the second color light-emitting unit 04, that is, the first color light-emitting unit 03 and the second color light-emitting unit 04 are in the same layer but have the same heights. Since the vertical projection of the third color light-emitting unit 06 on the first substrate 01 does not overlap with the vertical projection of the first color light-emitting unit 03 and the second color light-emitting unit 04 on the first substrate 01, the light emitted by the first color light-emitting unit 03, the second color light-emitting unit 04 and the third color light-emitting unit 06 do not overlap with each other, and there is less occlusion, so full-color display can be achieved and luminous efficiency can be improved.

[0046] Optional, reference Figure 1 and Figure 2 The full-color LED structure also includes: a mask layer 02, the mask layer 02 is located between the first color light-emitting unit 03 and the second color light-emitting unit 04, the mask layer 02 includes a plurality of first mask holes and a plurality of second mask holes, the first color light-emitting unit 03 is correspondingly arranged in the first mask hole, and the second color light-emitting unit 04 is correspondingly arranged in the second mask hole; the size of the first mask hole is larger than the size of the second mask hole.

[0047] The material of the mask layer 02 can be silicon dioxide (SiO 2 ) or silicon nitride (SiN x). The shapes of the first mask hole and the second mask hole can be any shape such as round, square and hexagonal. Each first mask hole corresponds to the growth of a first color light-emitting unit 03, and each second mask hole corresponds to the growth of a second color light-emitting unit 04. Under the same preparation conditions, the second color light-emitting unit 04 grown in the second mask hole of smaller size can be in the shape of a tetrahedron, emitting light in a transverse plane, while the first color light-emitting unit 03 grown in the first mask hole of larger size can be in the shape of a hexagonal pyramid, emitting light on an inclined surface. Optionally, the size of the first mask hole is equal to the size of the second mask hole; optionally, the size of the first mask hole is smaller than the size of the second mask hole.

[0048] Optionally, the aperture of the first mask hole is less than 20 μm.

[0049] By patterning and etching the aperture of the first mask hole to be less than 20 μm, the first color light emitting unit 03 grown in the first mask hole can be in the shape of a hexagonal pyramid.

[0050] Optionally, in a direction perpendicular to the first substrate 01, the cross section of the first color light emitting unit 03 is a triangle or a trapezoid. Optionally, the angle between the inclined surface of the first color light emitting unit 03 and the first substrate 01 is greater than 50°.

[0051] Optional, reference Figure 1 and Figure 2 The full-color LED structure also includes: a first passivation layer 08, which is located on the side of the mask layer 02 away from the first substrate 01 and is arranged on the upper surface of the mask layer 02, playing the role of isolation and insulation between the first color light-emitting unit 03 and the second color light-emitting unit 04.

[0052] Optionally, the first color light-emitting unit 03 is a blue LED unit, the second color light-emitting unit 04 is a green LED unit, and the third color light-emitting unit 06 is a red LED unit. Optionally, the first substrate 01 is a silicon substrate, and GaN-based blue LED units and GaN-based green LED units are manufactured on the silicon substrate, and the second substrate 05 is a GaAs substrate, and InP-based red LED units are manufactured on the GaAs substrate; Optionally, the size of the silicon substrate is 8 inches or 12 inches, and the size of the GaAs substrate is 6 inches. Optionally, both the first substrate 01 and the second substrate 02 are silicon substrates, and the blue LED unit, the green LED unit, and the red LED unit are all made of GaN-based materials. The size of the first substrate 01 and the second substrate 02 can be 8 inches or 12 inches; considering the difficulty of alignment in the bonding process, the size of the first substrate 01 and the second substrate 02 remain consistent.

[0053] Among them, the blue LED unit, the green LED unit and the red LED unit can realize the colorization of the LED structure and achieve full-color display. Figure 1 and Figure 2 The first color light-emitting unit 03 includes a first semiconductor layer 31, a first light-emitting layer 032 and a second semiconductor layer 33 stacked in sequence, and the surface of the first light-emitting layer 032 away from the first substrate 01 is an inclined surface; the second color light-emitting unit 04 includes a first semiconductor layer 31, a second light-emitting layer 042 and a second semiconductor layer 33 stacked in sequence, and the surface of the second light-emitting layer 042 away from the first substrate 01 is parallel to the first substrate 01.

[0054] The first color light emitting unit 03 is a blue LED unit, and the three-dimensional shape of the first color light emitting unit 03 is a hexagonal pyramid or a hexagonal pyramid, so the surface of the first light emitting layer 032 away from the first substrate 01 is an inclined surface.

[0055] The third color light emitting unit 06 also includes a first semiconductor layer 31, a third light emitting layer 062, and a second semiconductor layer 33 stacked in sequence. The first semiconductor layer 31 and the second semiconductor layer 33 have different conductivity types, one of which is an N-type doped semiconductor layer and the other is a P-type doped semiconductor layer. The materials of the first semiconductor layer 31 and the second semiconductor layer 33 include one or more materials selected from AlN, GaN, AlGaN, or InGaN. It should be noted that, referring to Figure 1 , the first semiconductor layer 31 of the first color light emitting unit 03 and the first semiconductor layer 31 of the third color light emitting unit 06 are opposite to each other.

[0056] Optional, reference Figure 1 and Figure 2 The full-color LED structure further includes: an inclined conductive layer 151 , which is located on a side of the first semiconductor layer 31 of the first color light-emitting unit 03 away from the first light-emitting layer 032 .

[0057] The material of the inclined conductive layer 151 may be an indium tin oxide film, and the inclined conductive layer 151 is arranged on the side of the first semiconductor layer 31 of the first color light-emitting unit 03 away from the first light-emitting layer 032, so that the current distribution of the first semiconductor layer 31 is more uniform, and the electrons or holes in the first semiconductor layer 31 can uniformly enter the first light-emitting layer 032. Optionally, the material of the first sublayer 15 above the second color light-emitting unit 04 is an indium tin oxide film, and the first sublayer 15 is a planar structure parallel to the first substrate 01, and the first sublayer 15 and the inclined conductive layer 151 are manufactured at the same time.

[0058] Optional, reference Figure 1 and Figure 2The full-color LED structure also includes: a transparent conductive layer 11, which is located on a side of the third color light-emitting unit 06 close to the first color light-emitting unit 03 and the second color light-emitting unit 04.

[0059] The material of the transparent conductive layer 11 may be an indium tin oxide film, which has good electrical conductivity and visible light transmittance. Figure 1 and Figure 2 The transparent conductive layer 11 is located between the first color light emitting unit 03 and the second color light emitting unit 04 and the third color light emitting unit 06, and covers the first passivation layer 08, the inclined conductive layer 151, the first color light emitting unit 03, the first sublayer 15 on the second color light emitting unit 04, and the surface of the third color light emitting unit 06. It should be noted that the transparent conductive layer 11 is located on the side of the third color light emitting unit 06 close to the first color light emitting unit 03 and the second color light emitting unit 04, and the transparent conductive layer 11 is electrically connected to the first color light emitting unit 03 and the second color light emitting unit 04 The first semiconductor layer 31 and the first semiconductor layer 31 of the third color light emitting unit 06 can therefore be used as a common electrode for the above three light emitting units, expand the area of ​​the contact point between the electrode and the first semiconductor layer 31, and improve the manufacturing yield of the contact between the electrode and the first semiconductor layer 31.

[0060] Optional, reference Figure 1 and Figure 2 The full-color LED structure also includes: a driving unit layer 12, which is arranged on the side of the third color light-emitting unit 06 away from the first substrate 01, and the driving unit layer 12 includes a plurality of driving units; a plurality of first electrodes 241, each first electrode 241 is electrically connected to the transparent conductive layer 11 and each light-emitting unit, and each driving unit provides an electrical signal to each light-emitting unit through the first electrode 241 and the transparent conductive layer 11.

[0061] Optionally, the full-color LED structure also includes a second electrode 242, wherein the first electrode 241 provides the same electrical signal to each light-emitting unit, which is equivalent to a common electrical signal, and the second electrode 242 provides the same or different electrical signals to each light-emitting unit, which is equivalent to a driving electrical signal. Therefore, the multiple driving units of the driving unit layer independently control the first color light-emitting unit 03, the second color light-emitting unit 04 and the third color light-emitting unit 06. After pressurization, the light-emitting units will not affect each other, so full-color display can be achieved and the luminous efficiency can be improved.

[0062] Optional, full-color LED configurations include: Figure 3 The first embodiment of the present invention provides a light emitting unit arrangement diagram, referring to Figure 3, a plurality of light emitting unit groups 1 arranged in an array; each light emitting unit group 1 includes a first color light emitting unit 03, a third color light emitting unit 06 and a second color light emitting unit 04; or, Figure 4 is another arrangement diagram of light emitting units provided in the first embodiment of the present invention, refer to Figure 4 Each light emitting unit group 1 includes a first color light emitting unit 03 , two third color light emitting units 06 and one second color light emitting unit 04 .

[0063] in, Figure 3 and Figure 4 These are all examples of two different light emitting unit groups 1 , and different light emitting unit groups 1 can be set according to user needs to achieve full-color display. Figure 3 Each light-emitting unit group 1 includes a first color light-emitting unit 03, a third color light-emitting unit 06 and a second color light-emitting unit 04, and the light-emitting units in each light-emitting unit group 1 are arranged in the order of the first color light-emitting unit 03, the third color light-emitting unit 06 and the second color light-emitting unit 04 along the first direction x; Figure 4 Each light emitting unit group 1 includes a first color light emitting unit 03, two third color light emitting units 06 and a second color light emitting unit 04, and the light emitting units in each light emitting unit group 1 are arranged in the order of the third color light emitting unit 06, the first color light emitting unit 03, the third color light emitting unit 06 and the second color light emitting unit 04 along the first direction x. It should be noted that Figure 3 and Figure 4 The light-emitting unit is only illustrated as a hexagon, and the cross-sectional shape of the light-emitting unit is not limited; and, Figure 3 and Figure 4 The illustrated graphic dimensions do not limit the cross-sectional area of ​​the light-emitting unit.

[0064] Optional, Figure 5 is another light emitting unit arrangement diagram provided in the first embodiment of the present invention. Figure 3 It shows that the angle between the arrangement direction of light-emitting units of different colors and the arrangement direction of light-emitting units of the same color is 90°. Figure 5 It is illustrated that the angle between the arrangement direction of light-emitting units of different colors and the arrangement direction of light-emitting units of the same color is not 90°.

[0065] Optional, Figure 6 This is another light emitting unit arrangement diagram provided in the first embodiment of the present invention, in which two light emitting unit groups 1 form a delta arrangement.

[0066] Optional, Figure 7 This is another light emitting unit arrangement diagram provided in the first embodiment of the present invention, in which the light emitting unit group 1 forms a diamond-shaped arrangement.

[0067] Optional, Figure 8 is a structural schematic diagram of another full-color LED structure provided in the first embodiment of the present invention, referring to Figure 8 , a second passivation layer 07 is disposed between adjacent third color light emitting units 06; or, referring to Figure 1 A third color material layer 09 is disposed between adjacent third color light emitting units 06 , and the third color material layer 09 is separated from the third color light emitting unit 06 by a dividing groove 10 ; wherein the material of the third color material layer 09 is the same as that of the third color light emitting unit 06 .

[0068] Among them, reference Figure 8 In the process of preparing the third color light-emitting unit 06, a third color material layer 09 can be prepared on the second substrate, and the third color material layer 09 corresponding to the first color light-emitting unit 03 and the second color light-emitting unit 04 is removed to avoid the third color material layer 09 above being stimulated to emit light due to the light emission of the first color light-emitting unit 03 and the second color light-emitting unit 04, thereby affecting the light-emitting effect. The remaining third color material layer 09 is the third color light-emitting unit 06, and a second passivation layer 07 is provided between adjacent third color light-emitting units 06, and the second passivation layer 07 between the third color light-emitting units 06 corresponds to the second color light-emitting unit 04 or the third color light-emitting unit 06. Alternatively, referring to Figure 1 , a third color material layer 09 can be prepared on the second substrate, the third color material layer 09 corresponds to the first color light-emitting unit 03 and the second color light-emitting unit 04, and the non-corresponding area is the third color light-emitting unit 06, and the third color material layer 09 corresponding to the first color light-emitting unit 03 and the second color light-emitting unit 04 is not removed, thereby simplifying the manufacturing process; and the third color material layer 09 is separated from the third color light-emitting unit 06 by the separation groove 10, so that the light emitted by the first color light-emitting unit 03 will not be blocked by the second color light-emitting unit 04 or the third color light-emitting unit 06, thereby improving the luminous efficiency of the first color light-emitting unit 03.

[0069] Embodiment 2

[0070] The embodiment of the present invention provides a method for preparing a full-color LED structure based on the above embodiment. Fig. 9 is a flow chart of a method for preparing a full-color LED structure provided in Embodiment 2 of the present invention, Figures 10 to 13 is a schematic diagram of an intermediate structure of a full-color LED structure provided by the second embodiment of the present invention, referring to Fig. 9 , the preparation method comprises:

[0071] Step 100, reference Fig.10, a first color light-emitting unit 03 and a second color light-emitting unit 04 are prepared simultaneously on one side of the first substrate 01, and the preparation method can be selective epitaxial growth, and the first color light-emitting unit 03 and the second color light-emitting unit 04 are arranged in the same layer.

[0072] Step 200, reference Fig.11 , a third color material layer 09 is prepared on one side of the second substrate 05, and the preparation method can be epitaxial growth.

[0073] Step 300: Combine a first substrate and a second substrate so that a first color light emitting unit, a second color light emitting unit and a third color material layer are located between the first substrate and the second substrate.

[0074] Step 400: remove the second substrate.

[0075] Step 500, making a dividing groove, the dividing groove at least passes through the third color material layer to form multiple third color sub-layers, wherein the third color sub-layer whose vertical projection on the first substrate does not overlap with the vertical projection of the first color light-emitting unit and the second color light-emitting unit on the first substrate is a third color light-emitting unit.

[0076] Among them, reference Fig.12 , the separation groove 10 penetrates the third color material layer, the transparent conductive layer 11 and the first passivation layer 08, and the separation groove 10 is made on the side of the third color material layer 09 away from the first substrate 01, and the separation groove 10 is arranged between the first color light-emitting unit 03 and the second color light-emitting unit 04; Fig.13 The dividing groove 10 passes through the third color material layer 09; the dividing groove 10 is used to divide the third color material layer 09 into multiple third color sub-layers, and the third color sub-layer whose vertical projection on the first substrate 01 does not overlap with the vertical projection of the first color light-emitting unit and the second color light-emitting unit on the first substrate 01 is a third color light-emitting unit.

[0077] Optional, Fig.14 yes Fig. 9 A detailed flowchart of step 300 in FIG. Figures 14 to 16 This is a schematic diagram of an intermediate structure of a full-color LED structure provided by the second embodiment of the present invention, step 300, combining the first substrate 01 and the second substrate 05, and further comprising:

[0078] Step 310, reference Fig.15 A first transparent conductive layer 13 is formed on a side of the first color light emitting unit 03 and the second color light emitting unit 04 away from the first substrate 01 .

[0079] Step 320, reference Fig.16A second transparent conductive layer 14 is formed on a surface of the third color material layer 09 away from the second substrate 05 .

[0080] Step 330, reference Fig.17 , bonding the second transparent conductive layer 13 and the first transparent conductive layer 14 to form a transparent conductive layer 11.

[0081] Among them, the materials of the first transparent conductive layer 13 and the second transparent conductive layer 14 are both indium tin oxide films, which can be formed by deposition. There is an intermolecular force between the two indium tin oxide films. The second transparent conductive layer 14 and the first transparent conductive layer 13 can be directly bonded to form the transparent conductive layer 11 without using other bonding materials.

[0082] Optional, reference Fig.17 , preparing a first color light emitting unit 03 and a second color light emitting unit 04 simultaneously on one side of the first substrate 01, the first color light emitting unit 03 and the second color light emitting unit 04 are arranged in the same layer, and further comprising:

[0083] A mask layer 02 is prepared on a first substrate 01, wherein the mask layer 02 includes a plurality of first mask holes and a plurality of second mask holes, wherein the size of the first mask holes is larger than the size of the second mask holes;

[0084] Among them, the first mask hole and the second mask hole can be prepared by patterned etching, and then the first color light-emitting unit 03 and the second color light-emitting unit 04 are simultaneously prepared in the first mask hole and the second mask hole by selective epitaxial growth, thereby simplifying the preparation process of light-emitting units of different colors; wherein the first color light-emitting unit 03 is correspondingly formed in the first mask hole, and the second color light-emitting unit 04 is correspondingly formed in the second mask hole.

[0085] Optionally, the first color light emitting unit 03 is a blue light LED unit, and the surface of the first color light emitting unit 03 away from the first substrate 01 is an inclined surface. Fig.18 yes Fig.14 A detailed flowchart of step 310 in FIG. Figures 19 to 23 Schematic diagram of an intermediate structure of a full-color LED structure provided by the second embodiment of the present invention, wherein the preparation method further comprises:

[0086] Step 311: fabricate a first sublayer above the first color light-emitting unit and the second color light-emitting unit.

[0087] The material of the first sub-layer 15 is an indium tin oxide film. Fig.19 , a first sub-layer 15 is deposited over the first color light emitting unit 03 and the second color light emitting unit 04. Fig. 20, remove the first sublayer 15 above the mask layer 02 to avoid mutual interference between the first color light-emitting unit 03 and the second color light-emitting unit 04 after being powered on.

[0088] Step 312, reference Fig.21 , a first passivation layer 08 is formed on the first sub-layer 15 and the mask layer 02 .

[0089] Step 313, reference Fig. 22 The first passivation layer 08 is planarized until the first sublayer 15 on the first color light emitting unit 03 and the second color light emitting unit 04 is exposed, and the first sublayer 15 on the first color light emitting unit 03 forms an inclined conductive layer 151. The planarization process may be chemical mechanical polishing (CMP).

[0090] Step 314, reference Fig.23 , a first transparent conductive layer 13 is formed on the first sub-layer 15 and the first passivation layer 08. The first transparent conductive layer 13 is formed by whole-layer deposition.

[0091] Optional, Figure 24 to Figure 25 is a schematic diagram of an intermediate structure of a full-color LED structure provided by the second embodiment of the present invention, referring to Fig.24 When making the dividing groove 10, it also includes making the electrode through hole 20 corresponding to the light-emitting unit; Fig.25 , forming a fourth passivation layer 25, the fourth passivation layer 25 fills the segmentation groove 10 and the electrode through hole 20, and covers the surface of the third color light emitting unit 06 away from the first substrate 01; Figure 1 An electrode structure 24 is formed in the fourth passivation layer 25 of the electrode through hole 20, that is, the fourth passivation layer 25 is retained on the side wall of the electrode through hole 20, and the electrode structure 24 is made in the hole formed by etching, and the electrode structure 24 includes a plurality of first electrodes 241, and each first electrode 241 is electrically connected to the transparent conductive layer 11 and each light-emitting unit; a driving unit layer 12 is formed on the side of the third color light-emitting unit 06 away from the first substrate 01; wherein the driving unit layer 12 includes a plurality of driving units, and each driving unit provides an electrical signal to each light-emitting unit through the first electrode 241 and the transparent conductive layer 11.

[0092] The dividing grooves 10 and the electrode through holes 20 can be formed by etching at the same time, and a planarization process is performed after the fourth passivation layer 25 is formed. Fig.24 The electrode through hole 20 includes a first through hole 21 and a second through hole 22 , wherein the first through hole 21 penetrates the transparent conductive layer 11 , and the second through hole 22 penetrates the second semiconductor layer of each light emitting unit.

[0093] Specifically, a driving unit layer 12 is formed on a side of the third color light emitting unit 06 away from the first substrate 01, and each light emitting unit is electrically connected to the driving unit through an electrode structure 24. Fig.24 and Figure 1 The first semiconductor layer 31 of each light-emitting unit is electrically connected to the driving unit through the transparent conductive layer 11 and the first electrode 241, and the first electrode 241 provides a common electrical signal. The second semiconductor layer 33 of each light-emitting unit is electrically connected to the driving unit through the second electrode 242, and the second electrode 242 provides a driving electrical signal.

[0094] Optionally, the first through hole 21 penetrates to the corresponding first semiconductor layer 31 , and then the first semiconductor layer 31 is directly electrically connected to the driving unit through the first electrode 241 .

[0095] The method for preparing a full-color LED structure provided by the technical solution of the embodiment of the present invention can realize full-color display and improve luminous efficiency.

[0096] Embodiment 3

[0097] The embodiment of the present invention further provides a method for preparing a full-color LED structure based on the above embodiment. Fig.26 Flow chart of another method for preparing a full-color LED structure provided in Embodiment 2 of the present invention, the preparation method comprising:

[0098] Step 600: prepare a first color light-emitting unit and a second color light-emitting unit simultaneously on one side of a first substrate, and the first color light-emitting unit and the second color light-emitting unit are arranged in the same layer.

[0099] Step 700: Prepare a third color light-emitting unit on one side of the second substrate.

[0100] Step 800: Combine a first substrate and a second substrate so that a first color light-emitting unit, a second color light-emitting unit, and a third color light-emitting unit are located between the first substrate and the second substrate, and a vertical projection of the third color light-emitting unit on the first substrate does not overlap with a vertical projection of the first color light-emitting unit and the second color light-emitting unit on the first substrate;

[0101] Step 900: remove the second substrate.

[0102] Compared with the full-color LED structure provided in Example 2, in the full-color LED structure of Example 3, no third color material layer is included between adjacent third color light-emitting units. A unitized third color light-emitting unit 06 is first manufactured, and then the first substrate and the second substrate are combined and aligned so that the third color light-emitting unit 06 is located between the first color light-emitting unit 03 and the second color light-emitting unit 04.

[0103] Specifically, Fig. 27is a schematic diagram of a full-color LED structure provided by Embodiment 3 of the present invention, referring to Fig. 27 and Figure 2 After removing the second substrate, the method includes: forming a first through hole 21 penetrating the transparent conductive layer 11 and a second through hole 22 penetrating the second semiconductor layer of each light-emitting unit; depositing a second passivation layer 07 as a whole layer, and the second passivation layer 07 fills the first through hole 21 and the second through hole 22; etching the second passivation layer 07 penetrating the first through hole 21 and the second through hole 22 along a direction perpendicular to the plane where the first substrate 01 is located; and making an electrode structure 24 in the hole formed by etching.

[0104] A driving unit layer 12 is formed on the side of the third color light emitting unit 06 away from the first substrate 01; wherein the driving unit layer 12 includes a plurality of driving units, and the driving units are electrically connected to the light emitting units one by one through the electrode structure 24; the driving units are used to drive the corresponding light emitting units to emit light.

[0105] In the preparation method provided in the embodiment of the present invention, the inclined conductive layer 151, the first sublayer 15, the transparent conductive layer 11, the mask layer 02 and the first passivation layer 08 are prepared by the same preparation method as in the second embodiment. The preparation method of the full-color LED structure provided by the technical solution of the embodiment of the present invention can realize full-color display and improve luminous efficiency.

[0106] In some embodiments, Fig.28 is a schematic diagram of a full-color LED structure provided by Embodiment 3 of the present invention, referring to Fig.28 and Figure 1 Taking the full-color LED structure of the first embodiment as an example, the first substrate 01 is removed, and the light emitting direction of each light emitting unit is toward a direction away from the driving unit layer 12.

[0107] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

Claims

1. A full-color LED structure, characterized in that: include: A first substrate (01); A first color light-emitting unit (03) and a second color light-emitting unit (04) are arranged on one side of the first substrate (01), wherein the first color light-emitting unit (03) and the second color light-emitting unit (04) are arranged in the same layer and are prepared at the same time; A third color light-emitting unit (06) is arranged on a side of the first color light-emitting unit (03) and the second color light-emitting unit (04) away from the first substrate (01), and a vertical projection of the third color light-emitting unit (06) on the first substrate (01) does not overlap with a vertical projection of the first color light-emitting unit (03) and the second color light-emitting unit (04) on the first substrate (01).

2. The full-color LED structure according to claim 1, characterized in that: Also includes: A mask layer (02), the mask layer (02) being located between the first color light-emitting unit (03) and the second color light-emitting unit (04), the mask layer (02) comprising a plurality of first mask holes and a plurality of second mask holes, the first color light-emitting unit (03) being correspondingly arranged in the first mask holes, and the second color light-emitting unit (04) being correspondingly arranged in the second mask holes; The size of the first mask hole is greater than the size of the second mask hole.

3. The full-color LED structure according to claim 2, characterized in that: The aperture of the first mask hole is less than 20 μm.

4. The full-color LED structure according to claim 2, characterized in that: Also includes: A first passivation layer (08), the first passivation layer (08) is located on a side of the mask layer (02) away from the first substrate (01), and is arranged on an upper surface of the mask layer (02).

5. The full-color LED structure according to claim 1, characterized in that: The first color light emitting unit (03) is a blue light LED unit, the second color light emitting unit (04) is a green light LED unit, and the third color light emitting unit (06) is a red light LED unit.

6. The full-color LED structure according to claim 5, characterized in that: The first color light-emitting unit (03) comprises a first semiconductor layer (31), a first light-emitting layer (032) and a second semiconductor layer (33) which are stacked in sequence, and a surface of the first light-emitting layer (032) away from the first substrate (01) is an inclined surface; The second color light-emitting unit (04) comprises a first semiconductor layer (31), a second light-emitting layer (042) and a second semiconductor layer (33) stacked in sequence, and a surface of the second light-emitting layer (042) away from the first substrate (01) is parallel to the first substrate (01).

7. The full-color LED structure according to claim 6, characterized in that: Also includes: An inclined conductive layer (151), wherein the inclined conductive layer (151) is located on a side of the first semiconductor layer (31) of the first color light-emitting unit (03) away from the first light-emitting layer (032).

8. The full-color LED structure according to claim 1, characterized in that: Also includes: The transparent conductive layer (11) is located on a side of the third color light emitting unit (06) close to the first color light emitting unit (03) and the second color light emitting unit (04).

9. The full-color LED structure according to claim 8, characterized in that: Also includes: A driving unit layer (12), the driving unit layer (12) being arranged on a side of the third color light emitting unit (06) away from the first substrate (01), the driving unit layer (12) comprising a plurality of driving units; A plurality of first electrodes (241), each of the first electrodes (241) being electrically connected to the transparent conductive layer (11) and each of the light-emitting units, and each of the driving units providing an electrical signal to each of the light-emitting units via the first electrode (241) and the transparent conductive layer (11).

10. The full-color LED structure according to claim 1, characterized in that: include: A plurality of light-emitting unit groups (1) arranged in an array; each of the light-emitting unit groups (1) comprises a light-emitting unit (03) of the first color, a light-emitting unit (06) of the third color and a light-emitting unit (04) of the second color; or, Each of the light-emitting unit groups (1) comprises one light-emitting unit (03) of the first color, two light-emitting units (06) of the third color and one light-emitting unit (04) of the second color.

11. The full-color LED structure according to claim 1, characterized in that: A second passivation layer (07) is provided between adjacent third color light emitting units (06); or, A third color material layer (09) is arranged between adjacent third color light-emitting units (06), and the third color material layer (09) is separated from the third color light-emitting units (06) by a dividing groove (10); wherein the material of the third color material layer (09) is the same as that of the third color light-emitting units (06).

12. A method for preparing a full-color LED structure, characterized in that: include: A first color light-emitting unit (03) and a second color light-emitting unit (04) are simultaneously prepared on one side of a first substrate (01), wherein the first color light-emitting unit (03) and the second color light-emitting unit (04) are arranged in the same layer; Preparing a third color material layer (09) on one side of the second substrate (05); Combining the first substrate (01) and the second substrate (05) so that the first color light-emitting unit (03), the second color light-emitting unit (04) and the third color material layer (09) are located between the first substrate (01) and the second substrate (05); removing the second substrate (05); A dividing groove (10) is produced, wherein the dividing groove (10) at least penetrates the third color material layer (09) to form a plurality of third color sub-layers, wherein the third color sub-layer whose vertical projection on the first substrate (01) does not overlap with the vertical projection of the first color light-emitting unit (03) and the second color light-emitting unit (04) on the first substrate (01) is a third color light-emitting unit (06).

13. The preparation method according to claim 12, characterized in that: The first substrate (01) and the second substrate (05) are combined, and further include: forming a first transparent conductive layer (13) on a side of the first color light-emitting unit (03) and the second color light-emitting unit (04) away from the first substrate (01); forming a second transparent conductive layer (14) on a surface of the third color material layer (09) away from the second substrate (05); The second transparent conductive layer (14) and the first transparent conductive layer (13) are bonded to form a transparent conductive layer (11).

14. The preparation method according to claim 13, characterized in that: A first color light-emitting unit (03) and a second color light-emitting unit (04) are simultaneously prepared on one side of a first substrate (01), wherein the first color light-emitting unit (03) and the second color light-emitting unit (04) are arranged in the same layer, and further comprising: Preparing a mask layer (02) on the first substrate (01), the mask layer (02) comprising a plurality of first mask holes and a plurality of second mask holes, the size of the first mask holes being larger than the size of the second mask holes; A first color light-emitting unit (03) and a second color light-emitting unit (04) are simultaneously prepared in the first mask hole and the second mask hole by selective epitaxial growth; wherein the first color light-emitting unit (03) is correspondingly formed in the first mask hole, and the second color light-emitting unit (04) is correspondingly formed in the second mask hole.

15. The preparation method according to claim 14, characterized in that: The first color light emitting unit (03) is a blue light LED unit, and the surface of the first color light emitting unit (03) away from the first substrate (01) is an inclined surface. The preparation method further comprises: Manufacturing a first sublayer (15) above the first color light-emitting unit (03) and the second color light-emitting unit (04); forming a first passivation layer (08) above the first sub-layer (15) and the mask layer (02); The first passivation layer (08) is planarized until the first sublayer (15) on the first color light-emitting unit (03) and the second color light-emitting unit (04) is exposed, and the first sublayer (15) on the first color light-emitting unit (03) forms an inclined conductive layer (151); A first transparent conductive layer (13) is produced on the first sub-layer (15) and the first passivation layer (08).

16. The preparation method according to claim 13, characterized in that: When making the dividing groove (10), it also includes making an electrode through hole (20) corresponding to the light-emitting unit; forming a fourth passivation layer (25), wherein the fourth passivation layer (25) fills the segmentation groove (10) and the electrode through hole (20) and covers the surface of the third color light emitting unit (06) away from the first substrate (01); An electrode structure (24) is formed in the fourth passivation layer (25) of the electrode through hole (20), wherein the electrode structure (24) comprises a plurality of first electrodes (241), each of the first electrodes (241) being electrically connected to the transparent conductive layer (11) and each of the light-emitting units; A driving unit layer (12) is formed on a side of the third color light-emitting unit (06) away from the first substrate (01); wherein the driving unit layer (12) includes a plurality of driving units, and each of the driving units provides an electrical signal to each of the light-emitting units through the first electrode (241) and the transparent conductive layer (11).

17. A method for preparing a full-color LED structure, characterized in that: include: A first color light-emitting unit (03) and a second color light-emitting unit (04) are simultaneously prepared on one side of a first substrate (01), wherein the first color light-emitting unit (03) and the second color light-emitting unit (04) are arranged in the same layer; Preparing a third color light-emitting unit (06) on one side of the second substrate (05); The first substrate (01) and the second substrate (05) are combined so that the first color light-emitting unit (03), the second color light-emitting unit (04) and the third color light-emitting unit (06) are located between the first substrate (01) and the second substrate (05), and the vertical projection of the third color light-emitting unit (06) on the first substrate (01) does not overlap with the vertical projections of the first color light-emitting unit (03) and the second color light-emitting unit (04) on the first substrate (01); The second substrate (05) is removed.

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