Preparation method for full-color micro-led module, and full-color module

Abstract

The present application relates to a preparation method for a full-color Micro-LED module, and a full-color module. The preparation method comprises the following steps: preparing a blue Micro-LED chip array, and implanting boron ions into side walls of blue Micro-LED chips; flip-chip bonding the blue Micro-LED chip array to a driving substrate, and fixing the blue Micro-LED chip array and the driving substrate into a holder structure; fixing a metal-dielectric composite reflective layer on the holder structure; preparing a dielectric material framework layer on the metal-dielectric composite reflective layer, and spin-coating the dielectric material framework layer with a quantum dot layer to form a full-color Micro-LED module. According to the present application, the implantation of the boron ions can increase the resistivity of the side walls of the chips, effectively suppressing leakage and non-radiative recombination of carriers on the side walls of the chips; the metal-dielectric composite reflective layer has high transmittance for blue light and high reflectivity for green and red light, and can thus increase the light emitting intensity; and the dielectric material framework layer can enable double-excitation resonance in both transverse electric and transverse magnetic waveguide modes, thereby effectively broadening the resonance bandwidth, improving the overall color conversion efficiency.

Description

A preparation method of full-color Micro-LED module and full-color module Technical Field

[0001] The present application relates to the field of semiconductor lighting technology, and specifically to a method for preparing a full-color Micro-LED module and a full-color module. Background Art

[0002] Currently, micro-light-emitting diode (Micro-LED) display technology is a technology that miniaturizes and matrices traditional large-size LEDs, with device sizes less than 100μm. Although Micro-LED offers advantages over existing liquid crystal display (LCD) and organic light-emitting diode (OLED) technologies, such as high brightness, high contrast, and low power consumption, full-color Micro-LED displays still face technical bottlenecks.

[0003] Among the related technologies, the most direct way to achieve full color is to achieve it by mass-transferring red, green and blue Micro-LED chips to form pixel points, but this solution has very high requirements on the speed, accuracy and yield of mass transfer. Another color conversion method does not require the transfer of chips. By combining a monochromatic blue or ultraviolet Micro-LED array with a phosphor or quantum dot color conversion layer, green and red light can be generated to achieve full-color display. However, the color conversion efficiency of coating phosphors on Micro-LEDs is relatively low. Although this problem can be solved by reducing the size of the phosphors, this may lead to a decrease in quantum efficiency. In contrast, quantum dots have the advantages of narrow emission spectrum, wide absorption spectrum and high fluorescence intensity, and are therefore considered to be one of the best solutions for achieving Micro-LED full-color display.

[0004] However, the current Micro-LED chip has serious internal light loss, resulting in low light output efficiency, and the quantum dot color conversion efficiency is low, making it difficult to meet the industrialization requirements of Micro-LED full-color display.

[0005] Therefore, it is necessary to design a new full-color Micro-LED module preparation method and full-color module to overcome the above problems.

[0006] Summary of the Invention

[0007] The present application provides a method for preparing a full-color Micro-LED module and a full-color module, which can solve the technical problems in the related art that the internal light loss of the Micro-LED chip is serious, resulting in low light output efficiency, and the quantum dot color conversion efficiency is low.

[0008] In a first aspect, embodiments of the present application provide a method for preparing a full-color Micro-LED module, comprising the following steps:

[0009] Prepare a blue light Micro-LED chip array and implant boron ions into the sidewalls of the blue light Micro-LED chip;

[0010] Flip-chip bonding the blue Micro-LED chip array to the driver substrate, and fixing the blue Micro-LED chip array and the driver substrate into the support structure;

[0011] fixing a metal-dielectric composite reflective layer on the support structure;

[0012] A dielectric material skeleton layer is prepared on the metal-dielectric composite reflective layer, and a quantum dot layer is spin-coated on the dielectric material skeleton layer to form a full-color Micro-LED module.

[0013] In combination with the first aspect, in one embodiment, preparing a blue light micro-LED chip array and implanting boron ions into the sidewalls of the blue light micro-LED chip includes:

[0014] growing an undoped GaN layer on a sapphire substrate, and growing an n-GaN layer on the undoped GaN layer;

[0015] Continuing to grow a quantum well active layer on the n-GaN layer, and continuing to grow a p-GaN layer on the quantum well active layer;

[0016] Etching the p-GaN layer until the n-GaN layer is exposed and a step structure is formed;

[0017] Depositing a metal mask layer on the p-GaN layer, and performing boron ion implantation on the periphery of the metal mask layer to obtain a boron ion implantation region distributed in the p-GaN layer;

[0018] An n-pole contact metal is deposited on the n-GaN layer, and a p-pole contact metal is deposited on the metal mask layer.

[0019] In combination with the first aspect, in one embodiment, depositing a metal mask layer on the p-GaN layer and performing boron ion implantation on the periphery of the metal mask layer to obtain a boron ion implantation region distributed in the p-GaN layer includes:

[0020] Depositing a metal mask layer on the p-GaN layer to form a peripheral annular mask-free area between the peripheral edge of the metal mask layer and the peripheral edge of the p-GaN layer;

[0021] Boron ion implantation is performed in the peripheral annular mask-free area to obtain a boron ion implantation region distributed in the p-GaN layer.

[0022] In combination with the first aspect, in one embodiment, flip-chip bonding the blue Micro-LED chip array to the driver substrate and fixing the blue Micro-LED chip array and the driver substrate into a support structure includes:

[0023] The blue light Micro-LED chip array and the driving substrate are surrounded by plastic to form a bracket structure.

[0024] In combination with the first aspect, in one embodiment, fixing the metal-dielectric composite reflective layer on the support structure includes:

[0025] forming a silver nanoparticle array on a glass substrate and depositing a protective shell on the silver nanoparticles to form a metal dielectric core-shell structure;

[0026] An adhesive material is filled in the gap of the metal dielectric core-shell structure to form a metal dielectric composite reflective layer, and the glass substrate and the metal dielectric composite reflective layer are aligned and fixed to the support structure.

[0027] In combination with the first aspect, in one embodiment, forming a silver nanoparticle array on a glass substrate includes:

[0028] A silver thin layer is deposited on the glass substrate and then annealed in a N2 environment to allow the silver thin layer to undergo dewetting to form a disordered silver nanoparticle array with different diameters.

[0029] In combination with the first aspect, in one embodiment, the thickness of the silver thin layer is 14-16 nm, the annealing temperature is 400-450° C., and the annealing time is 5-6 min; the average diameter of the formed silver nanoparticles is 70-120 nm, and the average height is 25-40 nm.

[0030] In combination with the first aspect, in one embodiment, a dielectric material skeleton layer is prepared on the metal-dielectric composite reflective layer, and a quantum dot layer is spin-coated on the dielectric material skeleton layer to form a full-color Micro-LED module, including:

[0031] Depositing a dielectric material on the metal-dielectric composite reflective layer to form a dielectric material skeleton layer, and punching a through-hole array on the dielectric material skeleton layer;

[0032] Colloidal quantum dots are dispersed in a cyclohexane solution and then spin-coated on top of a dielectric material skeleton layer to form a full-color Micro-LED module.

[0033] In combination with the first aspect, in one embodiment, the thickness of the dielectric material skeleton layer is 110-120 nm, and the pitch of the through-hole array is 260-270 nm.

[0034] In a second aspect, an embodiment of the present application provides a full-color Micro-LED module, comprising: a driving substrate, on which a blue light Micro-LED chip is arrayed, and the sidewalls of the blue light Micro-LED chip are injected with boron ions; a support structure, which is coated on the driving substrate and the blue light Micro-LED chip, and a metal-dielectric composite reflective layer is fixed on the support structure; a dielectric material skeleton layer, which is fixed to the surface of the metal-dielectric composite reflective layer, and quantum dots are spin-coated on the dielectric material skeleton layer.

[0035] The beneficial effects of the technical solutions provided in the embodiments of the present application include:

[0036] By injecting boron ions into the sidewalls of the blue light Micro-LED chip, the injection of boron ions can increase the resistivity of the chip sidewalls, which can effectively suppress the leakage and non-radiative recombination of carriers on the chip sidewalls. The metal-dielectric composite reflective layer has high transmittance for blue light and high reflectivity for green and red light, which can increase the light output intensity. The dielectric material skeleton layer can cause dual-excitation resonance in both the transverse electric and transverse magnetic waveguide modes, thereby effectively widening the resonance bandwidth and improving the overall color conversion efficiency. This solves the technical problems in related technologies such as serious internal light loss in Micro-LED chips resulting in low light output efficiency and low color conversion efficiency of quantum dots. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the embodiments of the present application, 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 application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0038] FIG1 is a flow chart of a method for preparing a full-color Micro-LED module provided in an embodiment of the present application;

[0039] FIG2 is a schematic diagram of a structure of growing an undoped GaN layer on a sapphire substrate according to an embodiment of the present application;

[0040] FIG3 is a schematic diagram of a structure of growing an n-GaN layer on an undoped GaN layer according to an embodiment of the present application;

[0041] FIG4 is a schematic diagram of a structure of growing a quantum well active layer on an n-GaN layer according to an embodiment of the present application;

[0042] FIG5 is a schematic diagram of a structure of growing a p-GaN layer on a quantum well active layer according to an embodiment of the present application;

[0043] FIG6 is a schematic structural diagram of an n-GaN layer forming a step structure according to an embodiment of the present application;

[0044] FIG7 is a schematic structural diagram of depositing a metal mask layer on a p-GaN layer according to an embodiment of the present application;

[0045] FIG8 is a schematic diagram of a structure for forming a boron ion implantation region according to an embodiment of the present application;

[0046] FIG9 is a schematic diagram of the structure of depositing an n-pole contact metal according to an embodiment of the present application;

[0047] FIG10 is a schematic diagram of the structure of depositing a p-pole contact metal according to an embodiment of the present application;

[0048] FIG11 is a schematic diagram of the structure of a blue light emitting Micro-LED chip provided in an embodiment of the present application;

[0049] FIG12 is a schematic structural diagram of a full-color Micro-LED module provided in an embodiment of the present application;

[0050] FIG13 is a schematic structural diagram of a dielectric material skeleton layer provided in an embodiment of the present application.

[0051] In the picture:

[0052] 1. Blue Micro-LED chip; 11. Sapphire substrate; 12. Undoped GaN layer; 13. n-GaN layer; 14. Quantum well active layer; 15. p-GaN layer; 16. Metal mask layer; 17. Boron ion implantation area; 18. N-pole contact metal; 19. P-pole contact metal; 10. Insulation layer;

[0053] 2. Driving substrate; 3. Support structure; 4. Glass substrate;

[0054] 5. Metal-dielectric composite reflective layer; 51. Silver nanoparticles; 52. Protective shell; 53. Adhesive material;

[0055] 6. Dielectric material skeleton layer; 61. Through hole; 7. Quantum dot layer. DETAILED DESCRIPTION

[0056] In order to enable those skilled in the art to better understand the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. 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 are within the scope of protection of this application.

[0057] The embodiments of the present application provide a method for preparing a full-color Micro-LED module and a full-color module, which can solve the technical problems in the related art that the internal light loss of the Micro-LED chip is serious, resulting in low light output efficiency, and the quantum dot color conversion efficiency is low.

[0058] 1 , a method for preparing a full-color Micro-LED module according to an embodiment of the present application may include the following steps:

[0059] S1: Prepare an array of blue Micro-LED chips 1 and implant boron ions into the sidewalls of the blue Micro-LED chips 1. In this embodiment, defects often exist on the sidewall surfaces of the etched Micro-LED chips, which can exacerbate non-radiative recombination of carriers on the sidewalls, thereby reducing the chip's external quantum efficiency. Boron ions can be implanted at locations where defects exist on the sidewall surfaces of the blue Micro-LED chips 1.

[0060] S2: Flip-chip bonding the blue Micro-LED chip 1 array to the driving substrate 2, and fix the blue Micro-LED chip 1 array and the driving substrate 2 to the support structure 3. The bonding method here can be metal eutectic bonding or adhesive bonding.

[0061] S3: Fixing the metal-dielectric composite reflective layer 5 on the support structure 3 .

[0062] S4: preparing a dielectric material skeleton layer 6 on the metal-dielectric composite reflective layer 5, and spin-coating a quantum dot layer 7 on the dielectric material skeleton layer 6 to form a full-color Micro-LED module.

[0063] In this embodiment, the prepared blue light Micro-LED chip 1 array and driving substrate 2 are fixed in the support structure 3. The support structure 3 can protect the driving substrate 2 and the blue light Micro-LED chip 1. The metal dielectric composite reflective layer 5 is fixed on the light-emitting surface of the support structure 3, so that the bottom of the support structure 3 is connected to the driving substrate 2, and the top is directly or indirectly connected to the metal dielectric composite reflective layer 5. Taking the case where the support structure 3 is located below the metal dielectric composite reflective layer 5 as an example, the dielectric material skeleton layer 6 is fixed on the upper surface of the metal dielectric composite reflective layer 5.

[0064] Since defects often exist on the sidewall surfaces of the Micro-LED chip after etching, non-radiative recombination of carriers on the sidewalls is exacerbated, resulting in a decrease in the chip's external quantum efficiency. In this embodiment, boron ions are implanted into the sidewalls of the blue Micro-LED chip 1. This implantation of boron ions increases the resistivity of the chip sidewalls, effectively suppressing carrier leakage and non-radiative recombination on the chip sidewalls, thereby improving the electrical and optical performance of the Micro-LED. The metal-dielectric composite reflective layer 5 has high transmittance for blue light and high reflectivity for green and red light. Transmitted blue light, after passing through the spin-coated quantum dot film, is converted into green or red light, which either directly emits forward or passes downward through the metal-dielectric composite reflective layer 5 with a high probability of being reflected. This increases the light output intensity. Furthermore, the dielectric material skeleton layer 6 enables dual-excitation resonance in both the transverse electric and transverse magnetic waveguide modes, effectively widening the resonance bandwidth and improving the overall color conversion efficiency. This addresses the technical issues in related technologies such as low light output efficiency caused by severe internal light loss in the Micro-LED chip and low color conversion efficiency of the quantum dots.

[0065] 2 to 11 , in one embodiment, the steps of preparing an array of blue light emitting micro-LED chips 1 and implanting boron ions into the sidewalls of the blue light emitting micro-LED chips 1 may include:

[0066] S11: Growing an undoped GaN layer 12 on a sapphire substrate 11, and growing an n-GaN layer 13 on the undoped GaN layer 12, as shown in Figures 2 and 3. When epitaxially growing the undoped GaN layer 12, the epitaxial growth process is metal organic chemical vapor deposition (MOCVD), and the thickness of the sapphire substrate 11 is approximately 200 to 300 μm, the thickness of the undoped GaN layer 12 is approximately 1.8 to 2 μm, and the thickness of the n-GaN layer 13 is approximately 2.2 to 3 μm.

[0067] S12: Continue growing a quantum well active layer 14 on the n-GaN layer 13, and continue growing a p-GaN layer 15 on the quantum well active layer 14, as shown in Figures 4 and 5. The quantum well active layer 14 is preferably an InGaN / GaN multi-quantum well active layer 14, and the thickness of the InGaN / GaN multi-quantum well active layer 14 is about 100 to 150 nm, and the number of periods is 6; the thickness of the p-GaN layer 15 is about 0.5 to 1 μm.

[0068] S13: etching the p-GaN layer 15 until the n-GaN layer 13 is exposed and a step structure is formed, as shown in Figure 6. The etching technology is inductively coupled plasma etching technology (ICP).

[0069] S14: A metal mask layer 16 is deposited on the p-GaN layer 15, and boron ions are implanted around the metal mask layer 16 to form a boron ion implanted region 17 distributed within the p-GaN layer 15. The boron ion implanted region 17 has a high resistivity, as shown in Figures 7 and 8. In this embodiment, the metal mask layer 16 is preferably made of Ni metal; however, other metal materials may also be used.

[0070] S15: An n-pole contact metal 18 is deposited on the n-GaN layer 13, and then a rapid thermal annealing process can be performed in an N2 environment to establish an ohmic contact; and a p-pole contact metal 19 is deposited on the metal mask layer 16, and then an alloying process is performed in air, as shown in Figures 9 and 10. As shown in Figure 11, an insulating layer 10, such as a SiN insulating layer 10, can be deposited on the surface of the p-GaN layer 15, the metal mask layer 16, and the n-GaN layer 13. The deposition technology is plasma enhanced chemical vapor deposition (PECVD), and the thickness of the SiN insulating layer 10 is 100 to 120 nm.

[0071] In the process of preparing the blue light Micro-LED chip 1 in this embodiment, boron ions are injected from the periphery of the metal mask layer 16 to the side wall of the p-GaN layer 15, so that a boron ion injection region 17 is formed on the peripheral side wall of the p-GaN layer 15, which can effectively suppress the leakage and non-radiative recombination of carriers on the side wall of the p-GaN layer 15.

[0072] In the above embodiment, the n-pole contact metal 18 can be a metal stack formed by Ti, Al, Ni and Au, with corresponding thicknesses of 25-30 nm, 125-130 nm, 50-55 nm and 125-130 nm respectively; the annealing temperature is 850-900°C and the time is 30-35 s; the p-pole contact metal 19 can be a metal stack formed by Ni and Au, with corresponding thicknesses of 5-7 nm and 5-7 nm respectively, the alloying temperature is 550-600°C and the time is 15-18 min.

[0073] 7 and 8 , preferably, depositing a metal mask layer 16 on the p-GaN layer 15 and performing boron ion implantation on the periphery of the metal mask layer 16 to obtain a boron ion implantation region 17 distributed in the p-GaN layer 15 may include:

[0074] S141: Depositing a metal mask layer 16 on the p-GaN layer 15 to form a peripheral annular mask-free region between the outer edge of the metal mask layer 16 and the outer edge of the p-GaN layer 15. That is, in this embodiment, the area of ​​the metal mask layer 16 is smaller than the area of ​​the p-GaN layer 15, and the distance between the edge of the metal mask layer 16 and the edge of the p-GaN layer 15 is preferably 2 to 2.5 μm. The peripheral annular mask-free region is reserved for subsequent ion implantation.

[0075] S142: Perform boron ion implantation in the outer annular mask-free area to obtain a boron ion implantation area 17 distributed in the p-GaN layer 15. The dose of the boron ion implantation is 3 to 3.5×10 13 icons / cm 2 The beam energy is 60-65 kV, and the ions are mainly distributed in the p-GaN layer 15 after implantation.

[0076] In this embodiment, by providing the metal mask layer 16, the area on the p-GaN layer 15 where boron ions do not need to be injected can be shielded, while the edge area of ​​the p-GaN layer 15 (i.e., the outer annular unmasked area) is exposed, which is conducive to the injection of boron ions in specific areas.

[0077] As shown in FIG12 , in some optional embodiments, flip-chip bonding the blue Micro-LED chip array 1 to the driver substrate 2 and fixing the blue Micro-LED chip array 1 and the driver substrate 2 to the support structure 3 may include:

[0078] The blue Micro-LED chip array 1 and the driver substrate 2 are surrounded by plastic to form a support structure 3. The plastic here can be PPA (polyphthalamide). In this embodiment, the plastic is used to surround the chip and driver substrate 2, which not only insulates and protects the chip and driver substrate 2, but also supports the metal-dielectric composite reflective layer 5 and the dielectric material skeleton layer 6.

[0079] As shown in FIG12 , in one embodiment, fixing the metal-dielectric composite reflective layer 5 on the support structure 3 may include:

[0080] S31: Forming an array of silver nanoparticles 51 on a glass substrate 4, and depositing a protective shell 52 on the silver nanoparticles 51 to form a metal dielectric core-shell structure. The protective shell 52 may be made of TiO2. In this embodiment, a thin TiO2 layer is deposited on the silver nanoparticles 51 to form the metal dielectric core-shell structure, and the thickness of the TiO2 layer is 20 to 30 nm.

[0081] S32: Filling the gaps between the metal dielectric core-shell structures with adhesive material 53 to form a metal dielectric composite reflective layer 5, and aligning and fixing the glass substrate 4 and the metal dielectric composite reflective layer 5 to the support structure 3, so that the top of the support structure 3 is connected to the glass substrate 4. The adhesive material 53 may be PMMA (polymethyl methacrylate). In this embodiment, a metal dielectric core-shell structure is formed by using an array of silver nanoparticles 51 and a protective shell 52 deposited on the silver nanoparticles 51. Filling the gaps between adjacent metal dielectric core-shell structures with adhesive material 53 to form a metal dielectric composite reflective layer 5. The filled adhesive material 53 may be used to adhere and fix the dielectric material skeleton layer 6 in subsequent steps, thereby fixing the dielectric material skeleton layer 6 to the glass substrate 4.

[0082] Furthermore, in one embodiment, forming an array of silver nanoparticles 51 on the glass substrate 4 includes depositing a thin layer of silver on the glass substrate 4, then annealing the thin layer in an N2 environment to dehumidify the thin layer of silver, thereby forming an array of disordered silver nanoparticles 51 having varying diameters. In this embodiment, the metal-dielectric composite reflective layer 5 exhibits high transmittance in the blue band and high reflectance in the green and red bands. The width and peak values ​​of its transmission and reflection spectra can be adjusted by varying the thickness of the initial thin silver layer and the TiO2 layer. As the thickness of the initial thin silver layer increases, the blue shift in the absorption spectrum of the silver nanoparticles 51 causes a decrease in the blue light transmittance of the metal-dielectric composite reflective layer 5, and scattering between the nanoparticles also intensifies the reflection of blue light. Furthermore, as the thickness of the TiO2 layer increases, the peak values ​​of both the transmission and reflection spectra redshift. The metal-dielectric composite reflective layer 5, based on a metal-dielectric core-shell structure, can increase light output intensity by adjusting the width and peak values ​​of its transmission and reflection spectra.

[0083] Preferably, in the above embodiment, the thickness of the silver thin layer is 14-16 nm, the annealing temperature is 400-450° C., and the annealing time is 5-6 min; the average diameter of the formed silver nanoparticles 51 is 70-120 nm, and the average height is 25-40 nm.

[0084] As shown in FIG. 12 and FIG. 13 , in one embodiment, a dielectric skeleton layer 6 is prepared on the metal-dielectric composite reflective layer 5 , and a quantum dot layer 7 is spin-coated on the dielectric skeleton layer 6 to form a full-color Micro-LED module, which may include:

[0085] S41: Deposit dielectric material on the metal-dielectric composite reflective layer 5 to form a dielectric material skeleton layer 6, and punch an array of through holes 61 on the dielectric material skeleton layer 6; wherein, the dielectric material can be Si3N4 or silicon dioxide, and Si3N4 is preferred in this embodiment, that is, deposit a Si3N4 film on the metal-dielectric composite reflective layer 5, and then use dual-beam laser interference lithography (LIL) and reactive ion etching (RIE) technology to punch an array of through holes 61 on the dielectric material skeleton layer 6 to generate a two-dimensional lateral photonic crystal structure.

[0086] S42: Colloidal quantum dots are dispersed in a cyclohexane solution and then spin-coated on top of the dielectric material skeleton layer 6 to form a full-color Micro-LED module. Specifically, a core / shell / shell structure of CdSe / CdS / ZnS colloidal quantum dots can be dispersed in a cyclohexane solution and then spin-coated on top of the two-dimensional lateral photonic crystal structure to complete the quantum dot color conversion layer.

[0087] In this embodiment, the cyclohexane solution concentration is 1 wt %, and the thickness of the quantum dot film spin-coated on the dielectric material skeleton layer 6 is 20 to 30 nm. The quantum dot color conversion layer is composed of a Si3N4 two-dimensional lateral photonic crystal structure and a colloidal quantum dot film. The Si3N4 two-dimensional lateral photonic crystal structure designed in this embodiment has four-fold rotational symmetry and is independent of the polarization state of the excitation photons, making it compatible with non-polarized excitation sources. In addition, the high-refractive-index Si3N4 dielectric material skeleton layer 6 enables dual-excitation resonance in both the transverse electric (TE) and transverse magnetic (TM) waveguide modes, thereby effectively widening the resonant bandwidth and improving the overall color conversion efficiency.

[0088] Preferably, the thickness of the dielectric material skeleton layer 6 is 110-120 nm, and the pitch of the through hole 61 array is 260-270 nm. In this embodiment, the thickness of the Si3N4 film is 110-120 nm.

[0089] Referring to Figure 12, a full-color Micro-LED module provided in an embodiment of the present application may include: a driving substrate 2, on which a blue light Micro-LED chip 1 is arrayed, and the sidewalls of the blue light Micro-LED chip 1 are injected with boron ions; a support structure 3, which is coated on the outside of the driving substrate 2 and the blue light Micro-LED chip 1, and on which a metal-dielectric composite reflective layer 5 is fixed; a dielectric material skeleton layer 6, which is fixed to the surface of the metal-dielectric composite reflective layer 5, and on which quantum dots are spin-coated.

[0090] Furthermore, in one embodiment, the blue light Micro-LED chip 1 includes a sapphire substrate 11, an undoped GaN layer 12 is grown on the sapphire substrate 11, an n-GaN layer 13 is grown on the undoped GaN layer 12, an InGaN / GaN multi-quantum well active layer 14 is grown on the n-GaN layer 13, a p-GaN layer 15 is grown on the InGaN / GaN multi-quantum well active layer 14, a step structure is formed on the p-GaN layer 15, and a metal mask layer 16 is deposited on the p-GaN layer 15, boron ions are injected into the p-GaN layer 15 at the periphery of the metal mask layer 16, so that a boron ion injection region 17 is formed on the sidewall of the p-GaN layer 15, an n-pole contact metal 18 is provided on the n-GaN layer 13, a p-pole contact metal 19 is provided on the metal mask layer 16, and an insulating layer 10 is deposited on the surface of the blue light Micro-LED chip 1.

[0091] Furthermore, in one embodiment, a glass substrate 4 is fixed to the upper surface of the support structure 3, and a metal-dielectric composite reflective layer 5 is fixed on the glass substrate 4. The metal-dielectric composite reflective layer 5 includes silver nanoparticles 51 deposited on the glass substrate 4, and the silver nanoparticles 51 are coated with a protective shell 52 to form a metal-dielectric core-shell structure. The gaps in the metal-dielectric core-shell structure are filled with an adhesive material 53 to form the metal-dielectric composite reflective layer 5.

[0092] Furthermore, in one embodiment, the material of the dielectric material skeleton layer 6 is preferably Si3N4, and an array of through holes 61 is provided on the dielectric material skeleton layer 6. The through holes 61 pass through the dielectric material skeleton layer 6 from top to bottom, and quantum dots are spin-coated on the top of the dielectric material skeleton layer 6 to form a quantum dot color conversion layer.

[0093] The full-color Micro-LED module in this embodiment effectively suppresses sidewall carrier leakage and non-radiative recombination by injecting boron ions into the sidewalls, thereby producing a highly efficient blue-light Micro-LED chip 1. Furthermore, the metal-dielectric composite reflective layer 5, based on a metal-dielectric core-shell structure, increases the light output intensity of the quantum dot color conversion layer by adjusting the width and peak value of its transmission and reflection spectra. The quantum dot color conversion layer, with its two-dimensional lateral photonic crystal structure, effectively improves color conversion efficiency. Through these three unique approaches, this application addresses the issues of low light output efficiency in traditional Micro-LED chips and low quantum dot color conversion efficiency, providing a new approach for the industrialization of full-color Micro-LED displays.

[0094] In the description of this application, it should be noted that the terms "upper" and "lower" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application. Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be internal communication between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0095] It should be noted that, in this application, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprising a ..." does not exclude the presence of other identical elements in the process, method, article or device comprising the element.

[0096] The foregoing is merely a list of specific embodiments of the present application, intended to enable those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application is not limited to the embodiments shown herein, but is intended to conform to the broadest scope consistent with the principles and novel features of the present application.

Claims

1. A preparation method of a full-color Micro-LED module, characterized in that, It includes the following steps: Prepare an array of blue Micro-LED chips (1), and inject boron ions into the sidewalls of the blue Micro-LED chips (1); Flip-chip bond the array of blue Micro-LED chips (1) onto the driving substrate (2), and fix the array of blue Micro-LED chips (1) and the driving substrate (2) inside the bracket structure (3); Fix a metal-dielectric composite reflective layer (5) on the bracket structure (3); Prepare a dielectric material skeleton layer (6) on the metal-dielectric composite reflective layer (5), and spin-coat a quantum dot layer (7) on the dielectric material skeleton layer (6) to form a full-color Micro-LED module.

2. The preparation method according to claim 1, characterized in that, The step of preparing an array of blue Micro-LED chips (1) and injecting boron ions into the sidewalls of the blue Micro-LED chips (1) includes: Grow an undoped GaN layer (12) on a sapphire substrate (11), and grow an n-GaN layer (13) on the undoped GaN layer (12); Continue to grow a quantum well active layer (14) on the n-GaN layer (13), and continue to grow a p-GaN layer (15) on the quantum well active layer (14); Etch on the p-GaN layer (15) until the n-GaN layer (13) is exposed and a stepped structure is formed; Deposit a metal mask layer (16) on the p-GaN layer (15), and perform boron ion implantation on the periphery of the metal mask layer (16) to obtain a boron ion implantation region (17) distributed in the p-GaN layer (15); Deposit an n-pole contact metal (18) on the n-GaN layer (13), and deposit a p-pole contact metal (19) on the metal mask layer (16).

3. The preparation method according to claim 2, characterized in that, The step of depositing a metal mask layer (16) on the p-GaN layer (15) and performing boron ion implantation on the periphery of the metal mask layer (16) to obtain a boron ion implantation region (17) distributed in the p-GaN layer (15) includes: Deposit a metal mask layer (16) on the p-GaN layer (15), so that a peripheral annular maskless region is formed between the peripheral edge of the metal mask layer (16) and the peripheral edge of the p-GaN layer (15); Perform boron ion implantation in the peripheral annular maskless region to obtain a boron ion implantation region (17) distributed in the p-GaN layer (15).

4. The preparation method according to claim 1, characterized in that, The step of flip-chip bonding the array of blue Micro-LED chips (1) onto the driving substrate (2) and fixing the array of blue Micro-LED chips (1) and the driving substrate (2) inside the bracket structure (3) includes: Surround the peripheries of the array of blue Micro-LED chips (1) and the driving substrate (2) with plastic to form a bracket structure (3).

5. The preparation method according to claim 1, characterized in that, The step of fixing a metal-dielectric composite reflective layer (5) on the bracket structure (3) includes: Form an array of silver nanoparticles (51) on a glass substrate (4), and deposit a protective shell (52) on the silver nanoparticles (51) to form a metal-dielectric core-shell structure; An adhesion material (53) is filled in the gap of the metal-dielectric core-shell structure to form a metal-dielectric composite reflective layer (5), and the glass substrate (4) and the metal-dielectric composite reflective layer (5) are aligned and fixed to the bracket structure (3).

6. The preparation method according to claim 5, characterized in that, Forming an array of silver nanoparticles (51) on the glass substrate (4) includes: Depositing a silver thin layer on the glass substrate (4), and then annealing in an N2 environment to cause the silver thin layer to undergo dewetting to form an array of disordered silver nanoparticles (51) with different diameters.

7. The preparation method according to claim 6, wherein The thickness of the silver thin layer is 14 to 16 nm, the annealing temperature is 400 to 450 °C, and the annealing time is 5 to 6 min; The average diameter of the formed silver nanoparticles (51) is 70 to 120 nm, and the average height is 25 to 40 nm.

8. The preparation method according to claim 1, characterized in that, Preparing a dielectric material skeleton layer (6) on the metal-dielectric composite reflective layer (5), and spin-coating a quantum dot layer (7) on the dielectric material skeleton layer (6) to form a full-color Micro-LED module, including: Depositing a dielectric material on the metal-dielectric composite reflective layer (5) to form a dielectric material skeleton layer (6), and forming an array of through holes (61) in the dielectric material skeleton layer (6); Disperse the colloidal quantum dots in a cyclohexane solution, and then spin-coat on the top of the dielectric material skeleton layer (6) to form a full-color Micro-LED module.

9. The preparation method according to claim 8, wherein The thickness of the dielectric material skeleton layer (6) is 110 to 120 nm, and the pitch of the through hole (61) array is 260 to 270 nm.

10. A full-color Micro-LED module, characterized in that, It includes: A driving substrate (2) with blue Micro-LED chips (1) arrayed thereon, and boron ions are implanted into the side walls of the blue Micro-LED chips (1); A bracket structure (3) covering the driving substrate (2) and the blue Micro-LED chips (1), and a metal-dielectric composite reflective layer (5) is fixed on the bracket structure (3); A dielectric material skeleton layer (6) fixed on the surface of the metal-dielectric composite reflective layer (5), and quantum dots are spin-coated on the dielectric material skeleton layer (6).

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