TWI832455B - Microluminescent diode with dielectric frame and preparation method thereof - Google Patents

Abstract

The invention provides a microluminescent diode with a dielectric frame and a preparation method thereof. The microluminescent diode with a dielectric frame includes: an n-type doped layer epitaxy on an epitaxial substrate; A dielectric frame is formed on one of the epitaxial substrate and the n-type doped layer; a multiple quantum well layer is grown in the dielectric frame and is located on the n-type doped layer; a p-type doped layer Grown in the dielectric frame and located on the multiple quantum well layer; a first metal electrode is connected to the p-type doped layer; a second metal electrode is connected to one of the n-type doped layer and the epitaxial substrate and a protective layer covering the outer surface of the dielectric frame and the transparent current dispersion layer, and exposing the first metal electrode and the second metal electrode; thereby effectively avoiding defects caused by platform etching.

Description

Microluminescent diode with dielectric frame and preparation method thereof

The present invention relates to a micro-luminescent diode and a preparation method thereof, in particular to a micro-luminescent diode with a dielectric frame and a preparation method thereof.

With the advancement of the times, displays have become thinner, lighter and more power-saving. The mainstream display technology has shifted from the emerging OLED display to actively investing in Micro light emitting diode (Micro-LED) displays. Micro LED displays Due to its many excellent characteristics and feasibility of self-illumination, low power consumption, fast response time, high brightness, ultra-high contrast, wide color gamut, wide viewing angle, ultra-thin and light, long service life and adaptability to various operating temperatures, it is a leading international manufacturer. With the leadership of the industry and the active participation of the industry, it is expected to become the mainstream technology of the next generation of displays. Micro LED technology shrinks the size of traditional LEDs in the general millimeter (10 ^-3 m) class to less than 100 microns (10 ^-6 m), which is 1% of the original LED volume. However, during the production and assembly process, mass transfer technology is required to transfer the micron-level RGB three-color Micro LED chips grown on the epitaxial substrate (also known as the original substrate or the homogeneous substrate) to the display substrate (or the target substrate) On the other hand, matrix-arranged RGB pixels are addressed and controlled to achieve full color, thereby forming a complete Micro LED display.

However, the above-mentioned advantages, combined with the complexity and yield and output efficiency problems in the mass transfer process, create key challenges and major troubles. Since the size of the die after epitaxy and graining is quite small, accurately transferring millions of micron-level Micro LED die to the correct position on the display substrate has become a technical obstacle for the industry.

In order to get rid of the above-mentioned problem of massive transfer, some people have already proposed a technical solution to manufacture three RGB LED components or at least two of them on the same epitaxial substrate and lay them out according to the finished product requirements. The applicant has also proposed relevant precedents for this. case. In the manufacturing process of Micro-LED displays, three primary color light-emitting diodes of red, green and blue (RGB) are used to form the pixels of the unit. Currently, the main manufacturing technology requires a mixture of nitrides and phosphides. (Phosphides) series of light-emitting diodes can meet the needs of the three primary colors. When light-emitting diodes of different material systems are mixed, different heating and attenuation characteristics directly affect the quality of image presentation; different electrical driving characteristics directly lead to the complexity of display module drive design. Therefore, if a direct-emitting RGB (red, green, and blue) three-primary color light-emitting diode is realized on the same material system, it will not only help solve the above problems, but also reduce the complexity of the process and reduce the complexity of the process by eliminating the color light conversion mechanism such as phosphors. The loss of energy efficiency caused by conversion will be more beneficial to the development of Micro LED technology.

Indium gallium nitride InxGa1-xN epitaxial material is one of the material systems currently used to make mainstream blue light-emitting diodes. In theory, it can cover the entire visible light emission range by controlling the proportion of indium gallium solid solution. Indium gallium nitride benefits from its ability to Direct energy gap (energy gap) characteristics are also expected to have better luminous efficiency, especially blue light mass production technology is mature, so it has received more attention than other material systems. It is necessary to produce direct red, green and blue with similar control conditions and good performance. Light-emitting diodes (RGB direct LED) have great potential. However, limited by the substrate, red light-emitting diodes based on InxGa1-xN epitaxial materials are currently facing technical bottlenecks. To achieve a suitable luminous band for red light, the In content ratio of InxGa1-xN epitaxial materials needs to be increased. , in the epitaxial manufacturing process, it is necessary to increase the In content by reducing the epitaxial temperature, etc., but it faces obstacles such as the epitaxial quality does not meet the application specifications. Therefore, before the red-light InGaN-based wafer technology matures, the red-light AlGaInP-based wafer will still be the main choice for direct light-emitting wafers.

However, on the other hand, Micro-LEDs are facing the problem of rapid decline in external quantum efficiency (EQE) as the size of the crystal grains is greatly reduced. The size of Micro-LED components needs to be reduced to less than 5~10um in order to reach a lower cost level, and then display products can be LCD and OLED displays compete on price; the EQE level of existing general-sized blue LED components reaches 80%. However, the EQE of blue LED components shrunk to 5~10um is usually only 20% or lower; such EQE cannot support the ability to surpass LCD , OLED display performance products; therefore, the low EQE problem of Micro-LED components must be effectively solved in order to enter the highly competitive consumer market.

The root cause of the problem of low EQE comes from the significant defect effect on the sidewall of the wafer; sidewall defects include structural damage, foreign contaminants, and dangling bonds, etc. These defects will cause Shockley-Read-Hall (SRH) non-linearity on the sidewall surface. Radiation carrier recombination effect. Relevant research and analysis have confirmed that these wafer sidewall defects are mainly caused by mesa etch of LED wafers. Generally, the standard etching process of LED wafers uses ICP RIE dry etching, which uses high-energy plasma, ion bombardment and chemical reactions. The above-mentioned defects are left on the etched sidewall surface. The sidewalls of general-sized LED components have non-radiative recombination effects caused by the aforementioned defects. As the size of the component shrinks, the proportion of the sidewall surface area to the overall surface area of the component increases. The impact of sidewall defects on the overall luminous efficiency of the component becomes more and more significant. Entering the Micro-LED size Both blue and green InGaN-based wafers or red-light AlGaInP-based wafers show a rapid decline in EQE. In particular, AlGaInP-based wafers have a larger surface recombination rate and carrier diffusion length (carrier diffusion length) than InGaN-based wafers, so the EQE decreases. more significant.

Micro-LED dies face low EQE problems, mainly due to sidewall defects caused by wafer platform etching (mesa etch). At present, the most important improvement plan is to make up for the defects caused by platform etching through subsequent defect removal or repair processes such as passivation layer coating or chemical treatment of sidewall surfaces. Among them, the passivation layer coating currently uses atomic layer deposition (ALD, atomic layer deposition) Al ₂ O ₃ passivation layer to achieve the best results, which is better than the improvement benefits of other processes such as PECVD and materials such as SiO2; the passivation layer is related to improving the optical properties of the component. The combination of reflector for extraction efficiency (LEE) has also become an important research and development topic; the defect removal process after platform etching is currently often chemically treated with KOH or NH4S; N ₂ plasma treatment is also a defect repair after platform etching One of the manufacturing processes.

However, the various technical solutions mentioned above wait until the sidewall defects have been formed, and then use subsequent additional processes to remove or repair the defects. They are all solutions that increase the number of steps and make the process more complex, which will only affect the manufacturing yield and output efficiency. resulting in further restrictions. How to avoid sidewall defects and damage caused by platform etching in advance and completely eliminate the problem of EQE decline can truly achieve the technical effect of removing fuel from the bottom of the cauldron.

The detailed features and advantages of the present invention are described in detail below in the implementation mode. The content is sufficient to enable anyone skilled in the relevant art to understand the technical content of the present invention and implement it according to the content disclosed in this specification, the patent scope and the drawings. , anyone familiar with the relevant art can easily understand the relevant objectives and advantages of the present invention.

One object of the present invention is to provide a micro-light emitting diode with a dielectric frame. By first forming the dielectric frame and epitaxying the dielectric frame, the Micro LED caused by platform etching can be completely avoided. Defects and damage on the side wall can be solved to solve the problem of rapid decline in external quantum efficiency (EQE), thereby improving the luminous efficiency of Micro LED.

Another object of the present invention is to provide a micro-light emitting diode with a dielectric frame. By preforming the dielectric frame with a predetermined layout, different colors of Micro LED wafers can be epitaxially placed in different frames on the same substrate. grains, so that multi-color grains can be formed on a single substrate to form full-color pixels.

Another object of the present invention is to provide a micro-light emitting diode with a dielectric frame. The dielectric frame can be selected with an inner wall that slopes inward from top to bottom, so that the multiple quantum well layer and the p-type doped layer can be The stress during epitaxy is relieved.

Another object of the present invention is to provide a micro-light-emitting diode with a dielectric frame, which can use a dielectric frame with an outer side tilting outward from top to bottom to improve light extraction efficiency (Light Extraction Efficiency).

Yet another object of the present invention is to provide a method for preparing a micro-light emitting diode with a dielectric frame, which completely avoids defects and damage to the side walls of the Micro LED caused by platform etching.

The invention provides a micro-luminescent diode with a dielectric frame, which is formed on an epitaxial substrate. The micro-luminescent diode includes: an n-type doped layer epitaxially formed on the epitaxial substrate; A dielectric frame is formed on one of the epitaxial substrate and the n-type doped layer; a multiple quantum well layer is grown in the dielectric frame and is located on the n-type doped layer ; A p-type doping layer, grown in the above-mentioned dielectric frame and located on the multiple quantum well layer; a first metal electrode for conducting current to the p-type doping layer; a second metal electrode for conducting current Connected to one of the n-type doped layer and the epitaxial substrate; and a protective layer covering the outer surface of the dielectric frame and the transparent current dispersion layer, and exposing the first metal electrode and the Second metal electrode.

The method for preparing a micro-light emitting diode with a dielectric frame includes the following steps: a) forming a dielectric frame and an n-type doped layer on an epitaxial substrate; b) adding the n-type doped layer to A multiple quantum well layer is grown on the doped layer, and the multiple quantum well layer is located in the dielectric frame; c) a p-type doped layer is grown on the multiple quantum well layer, and the p-type doped layer is located in the dielectric frame; d) forming a first metal electrode for conducting current to the p-type doped layer, and forming a second metal electrode on one of the n-type doped layer and the epitaxial substrate; and forming a protective layer covering the outer surface of the dielectric frame and the transparent current dispersion layer and exposing the first metal electrode and the second metal electrode.

According to the micro-light emitting diode with a dielectric frame and its preparation method disclosed in the present invention, an amorphous dielectric layer such as silicon dioxide (SiO2) or silicon nitride (Si3N4) is used to first produce an appropriate amorphous The crystalline dielectric layer frame is then sequentially epitaxyed within the frame, so it can replace the Micro-LED structure manufactured by platform etching, thereby avoiding the effects of platform etching defects and solving the problem from the source. Solving the problem of rapid decline in EQE of Micro-LED not only solves the problem of rapid decline in EQE and effectively improves the luminous efficiency of Micro LED, but also improves the product yield and output efficiency, and can also improve the product yield and output efficiency on a single substrate. Multi-color crystal grains are formed to form full-color pixels; in particular, the shape of the dielectric frame can be selected to simultaneously solve stress problems during manufacturing and use, and improve the efficiency of light extraction.

1, 2, 3, 4: Micro-luminescent diodes

11, 11’, 21, 31, 41: Epitaxial substrate

12, 12’, 22, 32, 42: dielectric frame

13, 13’, 23, 33, 43: n-type doped layer

14, 14’, 24, 34, 44: multiple quantum well layers

15, 15’, 25, 35, 45: p-type doped layer

16, 16’, 26, 36, 46: Transparent current dispersion layer

17, 17’, 27, 37, 47: first metal electrode

18, 18’, 28, 38, 48: second metal electrode

19, 19’, 29, 39, 49: protective layer

51~57, 51’~57’: steps

120:dent

FIG. 1 is a flow chart of a first preferred embodiment of a method for manufacturing a micro-light emitting diode with a dielectric frame according to the present invention.

2A to 2E are schematic structural cross-sectional views of each step in the preparation process of the micro-light emitting diode with a dielectric frame according to the embodiment of FIG. 1 .

FIG. 3 is a flow chart of a second preferred embodiment of the method for manufacturing a micro-light emitting diode with a dielectric frame according to the present invention.

4A to 4F are schematic structural cross-sectional views of each step in the preparation process of the micro-light emitting diode with a dielectric frame according to the embodiment of FIG. 3 .

FIG. 5 is a schematic cross-sectional view of the structure of a micro-light emitting diode with a dielectric frame according to the third preferred embodiment of the present invention.

6 is a schematic cross-sectional view of the structure of a micro-light emitting diode with a dielectric frame according to the fourth preferred embodiment of the present invention.

7 is a schematic cross-sectional view of the structure of a micro-light emitting diode with a dielectric frame according to the fifth preferred embodiment of the present invention.

Specific examples are used to illustrate the implementation of the present invention, and those familiar with the art can easily understand other advantages and effects of the present invention from the content disclosed in the specification. The structures, proportions, sizes, etc. shown in the accompanying drawings are only used to match the content disclosed in the instructions and are for the understanding and reading of those familiar with this art. are not intended to limit the implementation of the present invention and have no technical substantive significance. Any structural modifications, changes in proportions, or size adjustments should still fall within the scope of the present invention without affecting the effectiveness and purpose of the present invention. within the scope of the present invention. Terms such as "one", "two", and "top" cited in this specification are only for convenience of understanding and are not used to limit the scope of the present invention. Changes or adjustments in their relative relationships will not cause substantial changes. Under the technical content, it is also regarded as the scope within which the present invention can be implemented.

As shown in Figure 1, the preparation method and preparation process of the micro-light emitting diode 1 with a dielectric frame in the first embodiment of the present invention is as follows. First, on the epitaxial substrate 11 taking sapphire as an example in Figure 2A, the steps 51 forms an n-type doped layer 13 of n-type gallium nitride (GaN) or n-type indium gallium nitride (InGaN), and in step 52, as shown in Figure 2B, another layer is formed on the n-type doped layer 13 For example, a dielectric layer of SiO ₂ or silicon nitride (Si ₃ N ₄ ), and as shown in FIG. 2C , the dielectric layer is etched to form a cavity 120 . After the cavity is etched out of the dielectric layer, The remaining portion will form the peripheral wall for limiting the subsequent epitaxial structure, so the etched dielectric layer is named dielectric frame 12 .

Subsequently, in step 53, according to the outer frame constraints of the dielectric frame 12, a multiple quantum layer of a material such as indium gallium nitride (InGaN) is epitaxially grown on the n-type doped layer 13 in the cavity 120. The well layer 14 serves as the main light-emitting layer; step 54 is also limited by the dielectric frame 12. As shown in FIG. 2D, a p-type gallium nitride (GaN) or p-type gallium nitride (GaN) is grown on the multiple quantum well layer 14. Indium gallium nitride (InGaN) is used as a p-type doped layer 15. At this time, the p-type doped layer 15 is flush with the dielectric frame 12 in the height direction. In order to disperse the current horizontally so that the electron-hole pair recombination position will not be too concentrated under the first metal electrode 17 and cause light shielding problems, step 55 forms a transparent layer such as indium tin oxide (ITO) above the p-type doped layer 15 The current dispersion layer 16 is on the p-type doped layer 15 .

Next, step 56 forms another cavity (not numbered) at the dielectric frame 12 next to the stack to expose the n-type doped layer 13, and fills it with metal to form a second cavity connected to the n-type doped layer 13. The metal electrode 18 and a first metal electrode 17 are formed on the transparent current dispersion layer 16, thereby forming a complete LED circuit. Finally, in step 57, a protective layer 19 is formed to cover the outer surface above the dielectric frame 12 and the transparent current dispersion layer 16, and the tops of the first metal electrode 17 and the second metal electrode 18 are exposed for conduction. The protective layer 19 may include a passivation layer or a reflective layer. The passivation layer is made of one of aluminum oxide (Al ₂ O ₃ ) and silicon dioxide (SiO ₂ ), and the reflective layer is a distributed Bragg reflector (DBR). ), used to improve the light output efficiency of the micro-light emitting diode 1.

Obviously, since the multiple quantum well layer and the p-type doping layer are bounded by the dielectric frame for epitaxy, the platform etching technology and the accompanying sidewall defects are eliminated, thereby overcoming the technical problem of reduced EQE and effectively improving Luminous efficiency of microluminescent diodes.

Of course, as those familiar with this technical field can easily understand, during subsequent processing, if there are requirements for isolation/passivation/mechanical strength, etc., a wider dielectric frame needs to be retained as support; however, as shown in Figure 3 and Figure 4A to As shown in 4F, the second embodiment of the present invention has the same epitaxial substrate 11', n-type doped layer 13', dielectric frame 12', multiple quantum well layer 14', p-type doped layer as the previous embodiment. layer 15', transparent current dispersion layer 16', first metal electrode 17', second metal electrode 18' and protective layer 19' and other structures, only in step 55', a step of further etching the dielectric frame 12' is added. The manufacturing process makes the width of the dielectric frame 12' narrower than that of the previous embodiment, so the protective layer 19' is covered to the outside of the dielectric frame 12', and the second metal electrode 18' is therefore at a height The direction extends lower.

In addition, in the foregoing embodiments, the dielectric frame is formed on the n-type doped layer, but people familiar with the art can easily understand that, as shown in Figure 5 of the micro-light emitting diode 2 with a dielectric frame of the present invention As shown in the third preferred embodiment, the dielectric frame 22 can also be directly formed on an epitaxial substrate 21 such as sapphire, and allow the n-type doping layer 23 and subsequent epitaxial multiple quantum well layers 24 thereon. , and the p-type doped layer 25, also epitaxially grows in the surrounding range defined by the above-mentioned dielectric frame 22; the transparent current dispersion layer 26 is located on the p-type doped layer 25, and is also higher than the above-mentioned dielectric frame 22 The solid frame 22; the first metal electrode 27 is conductively formed on the transparent current dispersion layer 26; the second metal electrode 28 is conductively formed. Connected to the n-type doped layer 23; and a protective layer 29 covering the outer surface of the dielectric frame 22 and the transparent current dispersion layer 26, and exposing the first metal electrode 27 and the second metal electrode 28.

Please refer to Figure 6 again. The fourth embodiment of the present invention has a micro-light emitting diode 3 with a dielectric frame, including: a gallium arsenide (GaAs) conductive substrate as the epitaxial substrate 31; an n-type doped layer 33. Epitaxy is formed on the epitaxial substrate 31; a dielectric frame 32 is formed on the epitaxial substrate 31, and the n-type doping layer 33 is located in the dielectric frame 32; a multiple quantum well layer 34 , grown in the above-mentioned dielectric frame 32 and located on the n-type doped layer 33; a p-type doped layer 35, grown in the above-mentioned dielectric frame 32 and located on the multiple quantum well layer 34; A transparent current dispersion layer 36 is located on the p-type doped layer 35; a first metal electrode 37 is connected to the transparent current dispersion layer 36; a second metal electrode 38 is connected to the epitaxial substrate 31; And a protective layer 39 covers the outer surface of the dielectric frame 32 and the transparent current dispersion layer 36, and exposes the first metal electrode 37 and the second metal electrode 38. In this example, the inner wall of the dielectric frame 32 is inclined inward from top to bottom, thereby relieving the stress of the multiple quantum well layer 34 and the p-type doped layer 35 during epitaxy.

Please refer to FIG. 7 again. The micro-light emitting diode 4 with a dielectric frame according to the fifth embodiment of the present invention includes: an epitaxial substrate 41; an n-type doped layer 43, which is epitaxially epitaxially formed on the epitaxial substrate 41. ; A dielectric frame 42 is formed on the n-type doped layer 43; a multiple quantum well layer 44 is grown in the dielectric frame 42 and is located on the n-type doped layer 43; a p Type doped layer 45 is grown in the dielectric frame 42 and is located on the multiple quantum well layer 44; a transparent current dispersion layer 46 is located on the p-type doped layer 45; a first metal electrode 47, Connected to the transparent current dispersion layer 46; a second metal electrode 48 connected to the n-type doped layer 43; and a protective layer 49 covering the dielectric frame 42 and the n-type doped layer 43 and the outer surface of the transparent current dispersion layer 46, and expose the first metal electrode 47 and the second metal electrode 48. In this example, not only the inner wall of the dielectric frame 42 is inclined inward from top to bottom, The stress of the multiple quantum well layer 44 and the p-type doped layer 45 during epitaxy can be relieved, and the outside of the dielectric frame 42 is also tilted outward from top to bottom, thereby benefiting the light extraction efficiency. promote.

Although in the above embodiments, a transparent current dispersion layer is formed on the p-type doped layer, those familiar with the art can easily understand that the first metal electrode itself can make the current distribution uniform and dispersed, and there is no need to provide The above-mentioned transparent current dispersion layer still belongs to the scope of rights of the present invention. After the above-mentioned Micro LED chips are manufactured on the epitaxial substrate, the chips can also be separated from the epitaxial substrate by laser lift off (LLO), grinding of the epitaxial substrate, or wet etching, and then the original chips can be separated. The Micro LED dies or Micro LED die arrays formed on the epitaxial substrate are transferred. Therefore, the scope claimed by the present invention also includes the Micro LED dies that exist on the epitaxial substrate or have been transferred from the epitaxial substrate. ; In addition, SiO2 can be pre-formed at the bottom of the Si3N4 dielectric frame as a stop layer for the frame etching, and then the SiO2 in the frame can be removed by wet etching to reduce dry etching damage to the n-epitaxial layer. This is usually based on improving the luminous efficiency or characteristics of the device. Relevant measures within the scope of the epitaxial process are all compatible with the dielectric frame process of the present invention, such as super lattice, electron blocking layer (EBL), cladding layer layer, etc., or the introduction of special heterogeneous material layers into multiple quantum well structures for the purpose of stress or band engineering. Such changes are still included in the scope of the following patent applications of the present invention.

In summary, the micro-light-emitting diode with a dielectric frame and its preparation method of the present invention have the dielectric frame, so it can avoid defects and damage to the side walls of the micro-light-emitting diode caused by platform etching, and solve the problem of external The problem of rapid decline in quantum efficiency, thereby improving the luminous efficiency of micro-light-emitting diodes. In addition, the inner wall of the dielectric frame is inclined inward from top to bottom, which can relieve the stress of the multiple quantum well layer and the p-type doped layer during epitaxy, and the The outer side is tilted outward from top to bottom, which is beneficial to improving the light extraction efficiency.

The above embodiments are only illustrative of the principles and effects of the present invention, but are not intended to limit the present invention. Even so, anyone skilled in the art can make modifications to the above embodiments without departing from the spirit and scope of the invention. Therefore, the protection scope of the present invention should be as listed in the patent application scope mentioned below.

1: Light emitting diode

11: Crystal substrate

12: Dielectric frame

13:n-type doped layer

14:Multiple quantum well layers

15: p-type doped layer

16:Transparent current dispersion layer

17: First metal electrode

18: Second metal electrode

19:Protective layer

Claims (9)

A micro-luminescent diode with a dielectric frame is formed on an epitaxial substrate. The micro-luminescent diode includes: an n-type doped layer epitaxially formed on the epitaxial substrate; a dielectric A mass frame formed on one of the epitaxial substrate and the n-type doped layer; a multiple quantum well layer grown in the above-mentioned dielectric frame and located on the n-type doped layer; a p A doped layer grows in the dielectric frame and is located on the multiple quantum well layer; a first metal electrode is used to conduct current to the p-type doped layer; a first metal electrode is located between the p-type doped layer and the The transparent current dispersion layer between the first metal electrodes is used to disperse the current of the first metal electrode to the p-type doping layer and the second metal electrode, and is connected between the n-type doping layer and the epitaxial substrate. one; and a protective layer covering the outer surface of the dielectric frame and the transparent current dispersion layer, and exposing the first metal electrode and the second metal electrode. The micro-light emitting diode with a dielectric frame as claimed in claim 1, wherein the dielectric frame is disposed on the epitaxial substrate, and the n-type doped layer is located in the dielectric frame. The micro-light emitting diode with a dielectric frame as described in claim 1, wherein when the second metal electrode is connected to the n-type doped layer, the epitaxial substrate is a sapphire substrate, and the The material of the n-type doped layer is one of n-type gallium nitride (GaN) and n-type indium gallium nitride (InGaN), the material of the multiple quantum well layer is indium gallium nitride (InGaN), and the p The material of the doped layer is one of p-type gallium nitride (GaN) and p-type indium gallium nitride (InGaN). The micro-light emitting diode with a dielectric frame as claimed in claim 1, wherein when the second metal electrode is connected to the epitaxial substrate, the epitaxial substrate is a gallium arsenide (GaAs) conductive substrate, and The material of the n-type doping layer is n-type aluminum gallium indium phosphide (AlGaInP), the material of the multiple quantum well layer is aluminum gallium indium phosphide (AlGaInP), and the material of the p-type doping layer is p-type phosphorus Aluminum gallium indium (AlGaInP). The micro-light emitting diode with a dielectric frame as described in claim 1, wherein the inner wall of the dielectric frame is inclined inward from top to bottom. The micro-light emitting diode with a dielectric frame as described in claim 1, wherein the material of the dielectric frame is at least one of silicon dioxide (SiO ₂ ) and silicon nitride (Si ₃ N ₄ ), The transparent current dispersion layer is made of indium tin oxide (ITO). The protective layer includes a passivation layer or a reflective layer. The passivation layer is made of aluminum oxide (Al ₂ O ₃ ) and silicon dioxide (SiO ₂ ). One of them, and the reflective layer is a distributed Bragg reflector (DBR). A method for preparing a micro-light emitting diode with a dielectric frame, the steps include: a) forming a dielectric frame and an n-type doped layer on an epitaxial substrate; b) forming the above n-type doped layer A multiple quantum well layer is grown on the doped layer, and the multiple quantum well layer is located in the dielectric frame; c) a p-type doped layer is grown on the multiple quantum well layer, and the p-type doped layer is located in the dielectric frame; and d) forming a first metal electrode for conducting current to the p-type doped layer, and forming a second metal electrode on one of the n-type doped layer and the epitaxial substrate ; and forming a protective layer that covers the outer surface of the dielectric frame and the transparent current dispersion layer and exposes the first metal electrode and the second metal electrode. The method for preparing a micro-light emitting diode with a dielectric frame as claimed in claim 7, wherein the above step a) further includes a1) forming the n-type doped layer on the epitaxial substrate, and a2) forming the A sub-step of placing a dielectric frame on the n-type doped layer. The method for preparing a micro-light-emitting diode with a dielectric frame as described in claim 7 further includes forming a transparent current dispersion layer on the p-type doped layer between the above-mentioned step c) and the above-mentioned step d). In step e) above, the transparent current dispersion layer is interposed between the p-type doped layer and the first metal electrode to disperse the current of the first metal electrode to the p-type doped layer.

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