TW202013782A - Micro led device for enhancing production yield of mass transfer - Google Patents

Abstract

The present invention provides a micro LED device sequentially coated with a first protection layer and a second protection layer thereon, so as to enhance production yield of mass transfer of an amount of the micro LED devices. Particularly, the first protection layer and the second protection layer make the micro LED device possesses excellent stress withstanding capability. Therefore, as a substrate transfer process is applied to single one micro LED device or a mass transfer process is applied to many micro LED devices, the micro LED device(s) is not leaded to surface distortion or die crack by the stress induced during the transfer process because of the protection of the two protection layers. On the other hand, in order to guarantee that the micro LED device make light emission normally, the present invention particularly lets the refractive index of the second protection layer be less than that of the first protection layer, and also lets the refractive index of the first protection layer be less than that of the second semiconductor material layer.

Description

Microluminescent diode capable of increasing mass transfer yield

The present invention relates to the technical field of light-emitting diodes (LEDs), and particularly refers to a micro-light-emitting diode that can increase the yield of a large amount of transfer.

Light-Emitting Diode (LED) is currently widely used as a light-emitting element. Because of its small size and long service life, it is widely used in human daily life. Generally, the diagonal length of the crystal grains of the light-emitting diode is between 200 microns and 300 microns. On the other hand, the light-emitting diode with a diagonal length between 50 microns and 60 microns is called a sub-millimeter light-emitting diode (Mini LED), and the diagonal length of the die is less than 50 microns The light-emitting diode is called Micro LED (μLED).

FIG. 1 shows a conventional micro-luminous diode display panel. The current technology can already use micro-luminescent diodes in display panels (or modules) as a sub-pixel. For example, in FIG. 1, a red light-emitting diode RLED', a green light-emitting diode GLED' and a blue light-emitting diode BLED' can constitute a micro-light emitting diode display panel 1' One pixel (pixel). The micro-luminescence diode display panel 1'further includes a substrate 10', and a plurality of electrical connection pads 101' are formed on the surface of the substrate 10' for electrically connecting the plurality of red-light micro-luminescence diodes RLED', the plurality of green light-emitting diodes GLED' and the plurality of blue light-emitting diodes BLED'. Generally speaking, the substrate 10' further includes a driving circuit for controlling the display of each sub-pixel or each pixel. It is worth noting that the display panel 1'with a resolution of 4K2K has 4096 × 2160 pixels; that is, the display panel 1'with a resolution of 4K2K will contain at least 24.88 million micro-emitting diodes. From this, it can be seen that how to arrange a large number of microluminescent diodes on the substrate 10' becomes a major manufacturing problem of the microluminescent diode display panel 1'.

A large amount of micron-level LED dies are arranged on a substrate or a circuit board through a high-precision device. This process is called mass transfer. U.S. Patent Publication No. 2018/0053742A1 discloses a method for mass transfer of electronic components. Correspondingly, FIG. 2A, FIG. 2B and FIG. 2C are process schematic diagrams showing the method of mass transfer of electronic components disclosed in US Patent Publication No. 2018/0053742A1. According to the disclosure of US Patent Publication No. 2018/0053742A1, the method for mass transfer of electronic components includes multiple process steps. First, in step 1, a plurality of LED dies 200' arranged in an array are formed on the surface of a substrate 112' (as shown in FIG. 2A). Next, in step 2, a temporary fixing film 120' is attached to the bottom surface of the substrate 112' (as shown in FIG. 2A), such as a blue tape (Blue tape).

Continuously, in step 3, laser etching equipment is used to make a plurality of scores on the surface of the substrate 112' (as shown in FIG. 2B); afterwards, the substrate 112' is turned over again, so that the substrate 112' The bottom of the is facing up (as shown in Figure 2B). Next, in step 4, the substrate 112' is cut along the score using a dicing machine to obtain a plurality of sub-substrates 113' (as shown in FIG. 2C). It is worth noting that each sub-substrate 113' has a plurality of LED dies 200' on its surface. Continue to use a vacuum suction machine to move the sub-substrate 113' onto a carrier substrate BS', so that the two electrodes of each LED die 200' and the bonding electrode preset on the surface of the carrier substrate BS' BE' reached an electrical connection.

Semiconductor component engineers who have actually used the aforementioned method of mass-transferring electronic components in the manufacturing plant should be aware that during the process of performing the flipping process of the substrate 112', some of the LED die 200' are subjected to external stress. damage. Moreover, during the process of moving the sub-substrate 113' using a vacuum suction machine, part of the LED die 200' may be damaged due to external stress. It is worth noting that the carrier substrate BS' is usually a printed circuit board or a flexible circuit board. Therefore, when the LED die 200' is transferred to the flexible circuit board in a large amount, the bending or bending of the flexible circuit board will also apply stress to the plurality of LED die 200' provided thereon, thus causing part of the LED die 200' Grain 200' damage.

It can be seen from the above description that although the prior art has been able to arrange a huge amount of micron-level LED die on a flexible substrate or a printed circuit board through the use of a blue film and a vacuum adsorption machine, the process of mass transfer However, it causes considerable damage or damage to the LED die. Obviously, such a massive transfer method still shows defects and deficiencies in practical applications; in view of this, the inventor of this case tried his best to research and invent, and finally developed a method that can improve the yield of massive transfer. Microluminescent diode.

The main purpose of the present invention is to propose a micro-luminescent diode that can increase the yield of a large amount of transfer. In particular, the present invention is to coat the surface of a micro-luminescent diode with a first protective layer and a second protective layer, so that the micro-luminescent diode covered with the first protective layer and the second protective layer can express Out of a higher degree of tolerance to external stress. In this way, when a single microluminescent diode is transferred to a substrate or a plurality of microluminescent diodes are transferred to a large amount, its surface layer or other regions will not be deformed, cracked or broken due to external stress . At the same time, in order to prevent the first protective layer and the second protective layer from affecting the normal light emission of the microluminescent diode, the present invention specifically makes the refractive index of the first protective layer smaller than that of the second semiconductor material layer, and at the same time refracts the second protective layer The rate is less than the first protective layer.

In order to achieve the above-mentioned main objective of the present invention, the inventor of the present invention provides an embodiment of the micro-luminescent diode that can increase the mass transfer yield, which includes: a substrate; a first semiconductor material layer formed on On the substrate; an active layer formed on the first semiconductor material layer; a second semiconductor material layer formed on the active layer; a first protective layer formed on the second semiconductor Above the material layer, and has a first opening and a second opening; wherein the first protective layer covers the side of the second semiconductor material layer, the side of the active layer, and the first semiconductor material layer at the same time Side and part of the surface; a second protective layer formed on the first protective layer and having a third opening corresponding to the first opening and a fourth opening corresponding to the second opening; a first An electrode formed on the first semiconductor material layer through the second opening and the fourth opening; and a second electrode formed on the second semiconductor through the first opening and the third opening Above the material layer; wherein, the refractive index of the first protective layer is smaller than the second semiconductor material layer, and the refractive index of the second protective layer is smaller than the first protective layer.

In addition, in order to achieve the above-mentioned main objective of the present invention, the inventor of the present invention also provides another embodiment of the microluminescent diode that can improve the mass transfer yield, which includes: a substrate; a first Bragg reflector Is formed on the substrate; a first semiconductor material layer is formed on the first Bragg reflector; an active layer is formed on the first semiconductor material layer; a second semiconductor material layer Is formed on the active layer; and a second Bragg reflector is formed on the second semiconductor material layer; a first protective layer covers the surface and sides of the second Bragg reflector, the The surface and sides of the second semiconductor material layer, the side of the active layer, the side of the first semiconductor material layer, and the side of the first Bragg reflector, and have a first opening and a second opening; a second A protective layer is formed on the first protective layer, and has a third opening corresponding to the first opening and a fourth opening corresponding to the second opening; a first electrode penetrates through the second An opening and the fourth opening are formed on the first semiconductor material layer; and a second electrode is formed on the second semiconductor material layer through the first opening and the third opening; wherein, the The refractive index of the first protective layer is smaller than that of the second semiconductor material layer, and the refractive index of the second protective layer is smaller than that of the first protective layer.

In order to be able to more clearly describe the micro-luminescent diode proposed by the present invention, which can increase the mass transfer yield, the following will explain the preferred embodiments of the present invention in detail with reference to the drawings.

First embodiment

Please refer to FIG. 3, which is a schematic perspective view of a first embodiment of a micro-luminescent diode of the present invention that can increase the mass transfer yield, and FIG. 4 shows the invention can improve the mass transfer yield. First cross-sectional view of a micro-luminescent diode. Engineers familiar with the design and manufacture of basic components of light-emitting diodes should be able to infer from FIG. 3 and FIG. 4 that the micro-luminescent diode 1 of the present invention that can increase the mass transfer yield (hereinafter referred to as "micro-luminescent diode") ) The first embodiment includes the basic structure of a standard light-emitting diode. As shown in FIGS. 3 and 4, the new type micro-luminescent diode 1 includes: a substrate 10, a first semiconductor material layer 11 formed on the substrate 10, and a first semiconductor material formed on the substrate 10 An active layer 12 on the layer 11, a second semiconductor material layer 13 formed on the active layer 12, a first protective layer 14, a second protective layer 15, a first electrode 16, and a first二electrode 17.

In particular, the first protective layer 14 is formed on the second semiconductor material layer 13 and has a first opening and a second opening. 4 shows that the first protective layer 14 covers the side of the second semiconductor material layer 13, the side of the active layer 12, and the side and part of the surface of the first semiconductor material layer 11. Here, it must be explained that FIG. 3 only shows that the first protective layer 14 only covers the surface of the second semiconductor material layer 13, and the main purpose is to expose each material layer of the microluminescent diode 1. On the other hand, the second protective layer 15 is formed on the first protective layer 14 and has a third opening corresponding to the first opening and a fourth opening corresponding to the second opening. As shown in FIGS. 3 and 4, the first electrode 16 is formed on the first semiconductor material layer 11 through the second opening and the fourth opening, and the second electrode 17 is passed through the first opening and the The third opening is formed on the second semiconductor material layer 13. Of course, the selection of the process materials for the first semiconductor material layer 11, the active layer 12 and the second semiconductor material layer 13 will be different along with the different emission colors. Traditionally, GaP, GaAsP, and AlGaAs are the main materials of the active layer 12, so that the active layer 12 can emit visible light with a wavelength ranging from 580nm to 740nm. However, as metal-organic chemical vapor deposition (MOCVD) process technology becomes more advanced, gallium nitride (GaN), aluminum gallium nitride (Al _x Ga _1-x N), or nitride Indium gallium (In _x Ga _1-x N) then becomes the main material of the active layer 12.

In general, the active layer 12 containing GaN can emit blue light. In addition, component engineers familiar with the design and manufacture of LED dies should know that by increasing the value of x (x<1), the active layer 12 including In _x Ga _1-x N can emit long-wavelength light. In contrast, by increasing the value of x (x<1), the active layer 12 including Al _x Ga _1-x N can emit light of a short wavelength. Here, it must be added that the active layer 12 made of GaN, Al _x Ga _1-x N or In _x Ga _1-x N is between the first semiconductor material layer 11 and the second semiconductor material layer 13 Form a single quantum well structure. Therefore, the first semiconductor material layer 11 and the second semiconductor material layer 13 can be regarded as a lower cladding layer and an upper cladding layer of the active layer 12; wherein, the first semiconductor material The manufacturing material of the layer 11 is N-type gallium nitride (n-type gallium nitride, n-GaN), for example, silicon (Si) doped gallium nitride. Conversely, the second semiconductor material layer 13 is made of p-type gallium nitride (p-type gallium nitride, p-GaN), such as magnesium-doped (Mg) gallium nitride. Further, the active layer 12 can also be designed as a multiple quantum well structure, thereby improving the recombination efficiency of the electron holes in the active layer 12. The multiple quantum well structure can be any of the following: multiple stacked structures of gallium nitride and indium gallium nitride (In _x Ga _1-x N), gallium nitride and aluminum gallium nitride (Al _x Ga _1-x N) Multi-stack structure of aluminum gallium nitride (Al _x Ga _1-x N) and indium gallium nitride (In _x Ga _1-x N).

Furthermore, the manufacturing materials of the first electrode 16 and the second electrode 17 can be any of the following: aluminum (Al), silver (Ag), titanium (Ti), nickel (Ni), gold (Au), copper (Cu), chromium (Cr), platinum (Pt), a combination of any two of the foregoing, or a combination of any two or more of the foregoing. It is worth emphasizing that the technical feature of the present invention is that, with the protective effect provided by the first protective layer 14 and the second protective layer 15, a single microluminescent diode 1 is performing substrate transfer or multiple microluminescent diodes When the body 1 is transferred in a large amount, its surface layer or other areas will not be deformed, cracked or collapsed due to the external stress. In particular, in order to prevent the first protective layer 14 and the second protective layer 15 from affecting the normal light emission of the active layer 12, the present invention specifically makes the refractive index of the first protective layer 14 smaller than the second semiconductor material layer 13, and At the same time, the refractive index of the second protective layer 15 is made smaller than that of the first protective layer 14.

As can be seen from the above description, the micro-luminescent diode 1 whose surface is covered with the first protective layer 14 and the second protective layer 15 can exhibit a high degree of tolerance to external stress. Therefore, when a single microluminescent diode 1 is transferring a substrate or a plurality of microluminescent diodes 1 are transferring a large amount, its surface layer or other areas will not be deformed, cracked or damaged by external stress. Collapsed. Of course, before the substrate transfer is completed, the substrate of the microluminescent diode 1 is usually a sapphire substrate or a spinel substrate. It is worth noting that after the substrate transfer is completed, the substrate of the microluminescent diode 1 may be replaced with a spinel substrate, a silicon carbide (SiC) substrate, a ceramic substrate, a polyimide (Polyimide) substrate, or a hard substrate Printed circuit board, or flexible printed circuit board. It must be added that the main manufacturing materials of the first semiconductor material layer 11 and the second semiconductor material layer 13 are all gallium nitride (GaN), and their refractive indexes and lattice constants are summarized in the following table (1). Table 1)

It is conceivable that when the process material of the first protective layer 14 is selected, the refractive index and lattice constant of the material must be considered simultaneously. In particular, the refractive index of the process material of the first protective layer 14 must be smaller than that of GaN, and it must be made of lattice constant matching GaN single crystal material, such as aluminum nitride (AlN), undoped nitride Gallium (undoped GaN), or zinc oxide (ZnO), the refractive index and lattice constant of these materials are collated in the following table (2). Table 2)

It must be added that the manufacturing material of the first protective layer 14 can also be a single crystal material with a lattice constant close to an integer multiple of GaN, for example: zinc sulfide (ZnS) of group II-VI semiconductor compound and group II-VI semiconductor Compound of zinc selenide (ZnSe). The refractive index and lattice constant of the aforementioned materials are summarized in the following table (3). table 3)

On the other hand, the manufacturing material of the second protective layer 15 may be any one of the following: aluminum oxide (Al ₂ O ₃ ), hafnium oxide (HfO ₂ ), magnesium oxide (MgO), zinc oxide (ZnO), or oxide Yttrium (Y ₂ O ₃ ). The refractive indexes of the aforementioned materials are summarized in the following table (4). Table 4)

Continuing to refer to FIG. 5, which is a second cross-sectional view of the microluminescent diode of the present invention that can increase the mass transfer yield. Comparing FIG. 4, it can be found that the microluminescent diode 1 shown in FIG. 5 further includes: A buffer layer BF formed on the second protective layer 15 and the first protective layer 14. In order to further improve the tolerance of the microluminescent diode 1 to external stress, the present invention inserts a buffer layer BF between the second protective layer 15 and the first protective layer 14. It is worth noting that if the second protective layer 15 is a first metal oxide layer, the buffer layer BF can be defined as a second metal oxide layer; and, a second metal element constituting the buffer layer BF The size of the atoms is smaller than that of a first metal element constituting the second protective layer 15. The exemplary materials of the first metal oxide layer and the second metal oxide layer are listed in the following table (5). table 5)

Second embodiment

Please refer to FIG. 6, which is a first cross-sectional view of a second embodiment of a microluminescent diode of the present invention that can increase the mass transfer yield. Engineers familiar with the design and manufacture of basic components of light-emitting diodes should be able to deduce from FIG. 6 that the present invention can improve the mass transfer yield of microluminescent diode 1 (hereinafter referred to as "microluminescent diode"). The second embodiment includes a basic structure of a vertical cavity surface emitting laser (VCSEL). As shown in FIG. 6, the structure of the new micro-luminescent diode 1 includes: a substrate 20, a first Bragg reflector 21 formed on the substrate 20, and a first Bragg reflector 21 formed on the substrate 20 A first semiconductor material layer 22, an active layer 23 formed on the first semiconductor material layer 22, a second semiconductor material layer 24 formed on the active layer 23, formed on the second semiconductor material layer A second Bragg mirror 25, a first protective layer 26, a second protective layer 27, a first electrode 28, and a second electrode 29 above the 24.

Generally speaking, the first Bragg reflection mirror (DBR) 21 is usually an n-type DBR formed by repeatedly stacking Al _X Ga _1-X As/Al _1-Y Ga _Y As, wherein the n-type DBR is transparent Obtained after doping silicon (Si) with undoped DBR. Conversely, the second Bragg mirror 25 is a p-type DBR, which is also formed by repeatedly stacking Al _X Ga _1-X As/Al _1-Y Ga _Y As, where p-type DBR can be carried out by undoped DBR Obtained after carbon (C) doping. On the other hand, the first semiconductor material layer 22 and the second semiconductor material layer 24 serve as a lower cladding layer and an upper cladding layer of the active layer 23 (ie, multiple quantum wells), respectively ), the manufacturing materials are n-type group III-V semiconductor composite and p-type group III-V semiconductor composite.

Continuing to refer to FIG. 7 and FIG. 8, they respectively show a second cross-sectional view and a third cross-sectional view of the second embodiment of the microluminescent diode of the present invention that can increase the mass transfer yield. The technical feature of the present invention is that a first protective layer 26 and a second protective layer 27 are formed in order on the surface of the vertical resonant cavity surface-emitting laser (VCSEL), and in particular, the first protective layer 26 is refracted The rate is smaller than that of the second semiconductor material layer 24, and at the same time, the refractive index of the second protective layer 27 is smaller than that of the first protective layer 26. Obviously, the present invention does not limit the second embodiment (ie, VCSEL) of the microluminescent diode 1 to be exactly the same as the structure shown in FIG. 6. For example, FIG. 7 shows that a (ring) oxide layer ACO is formed between the second semiconductor material layer 24 and the active layer 23, and the oxide layer ACO is used to define a light outcoupling aperture.

On the other hand, comparing FIG. 6 with FIG. 8, it can be found that FIG. 8 shows that an intermediate semiconductor material layer 24 a having the same material as the first semiconductor material layer 22 is formed between the second semiconductor material layer 24 and the active layer 23. The design is such that a tunnel junction TJ is formed at the junction of the intermediate semiconductor material layer 24a and the second semiconductor material layer 24, and from the junction to the inside of the second semiconductor material layer 24 extend. It is worth noting that in FIG. 8, a first bonding layer 22a is further inserted between the first Bragg reflector 21 and the first semiconductor material layer 22, and the second Bragg reflector 25 and the second semiconductor A second bonding layer 24b is also inserted between the material layers 24.

Similarly, the surface of the vertical cavity covered with the first protective layer 26 and the second protective layer 27 can emit a laser (ie, micro-luminescent diode 1) that can exhibit a higher tolerance to external stress. Therefore, when a single microluminescent diode 1 is transferring a substrate or a plurality of microluminescent diodes 1 are transferring a large amount, its surface layer or other areas will not be deformed, cracked or damaged by external stress. Collapsed. Of course, before the substrate transfer is completed, the substrate of the microluminescent diode 1 is usually a sapphire substrate or a spinel substrate. It is worth noting that after the substrate transfer is completed, the substrate of the microluminescent diode 1 may be replaced with a spinel substrate, a silicon carbide (SiC) substrate, a ceramic substrate, a polyimide (Polyimide) substrate, or a hard substrate Printed circuit board, or flexible printed circuit board.

It must be emphasized that the above detailed description is a specific description of possible embodiments of the present invention, but this embodiment is not intended to limit the patent scope of the present invention, and any equivalent implementation or change without departing from the technical spirit of the present invention, Should be included in the patent scope of this case.

<The present invention> 1: Micro-luminescent diodes that can increase the yield of mass transfer 10: substrate 11: The first semiconductor material layer 12: Active layer 13: Second semiconductor material layer 14: The first protective layer 15: Second protective layer 16: First electrode 17: Second electrode BF: buffer layer 20: substrate 21: The first Prague mirror 22: The first semiconductor material layer 23: Active layer 24: Second semiconductor material layer 25: Second Prague mirror 26: The first protective layer 27: Second protective layer 28: First electrode 29: Second electrode ACO: oxide layer 24a: intermediate semiconductor material layer TJ: Tunneling junction 22a: first junction layer 24b: second junction layer

<Xizhi> 112’: Substrate 200’: LED die 120’: Temporary fixation membrane 113’: daughter board BS’: carrier substrate BE’: splice electrode RLED’: red light-emitting diode GLED’: Green light micro-emitting diode BLED’: Blue light-emitting diode 1’: Display panel 101’: Electrical connection pad 10’: substrate

FIG. 1 shows a conventional micro-luminous diode display panel; FIGS. 2A, 2B, and 2C are process schematic diagrams showing the method of mass transfer of electronic components disclosed in US Patent Publication No. 2018/0053742A1; FIG. 3 shows the present A schematic perspective view of a first embodiment of a microluminescent diode capable of improving the mass transfer yield of the invention; FIG. 4 is a first cross-sectional view showing the microluminescent diode of the present invention capable of increasing the mass transfer yield Figure 5 is a second cross-sectional view of the microluminescent diode of the present invention that can increase the mass transfer yield; Figure 6 is a second cross-sectional view of the microluminescent diode of the present invention that can improve the mass transfer yield 7 is a second cross-sectional view of a second embodiment of a microluminescent diode of the present invention that can increase the mass transfer yield; and FIG. 8 is a second cross-sectional view of the present invention that can increase the mass transfer Third cross-sectional view of the second embodiment of the yield micro-emitting diode.

1: Micro-luminescent diodes that can increase the yield of mass transfer

10: substrate

11: The first semiconductor material layer

12: Active layer

13: Second semiconductor material layer

14: The first protective layer

15: Second protective layer

16: First electrode

17: Second electrode

Claims (20)

A micro light emitting diode includes: a substrate; a first semiconductor material layer formed on the substrate; an active layer formed on the first semiconductor material layer; a second semiconductor material layer Is formed on the active layer; a first protective layer is formed on the second semiconductor material layer and has a first opening and a second opening; wherein, the first protective layer covers both The side of the second semiconductor material layer, the side of the active layer, and the side and part of the surface of the first semiconductor material layer; a second protective layer is formed on the first protective layer and has a corresponding to A third opening of the first opening and a fourth opening corresponding to the second opening; a first electrode formed on the first semiconductor material layer through the second opening and the fourth opening; and A second electrode is formed on the second semiconductor material layer through the first opening and the third opening; wherein, the refractive index of the first protective layer is smaller than the second semiconductor material layer, and the first The refractive index of the second protective layer is smaller than that of the first protective layer. The micro-luminescent diode as described in item 1 of the patent application scope, wherein the substrate may be any of the following: spinel substrate, silicon carbide (SiC) substrate, sapphire (Sapphire) substrate, ceramic substrate, Polyimide (Polyimide) substrate, or printed circuit board. The micro light emitting diode as described in item 1 of the patent application range, wherein the manufacturing material of the first semiconductor material layer is N-type gallium nitride (n-GaN), and the second semiconductor The material of the material layer is p-type gallium nitride (p-GaN). The microluminescent diode as described in item 1 of the patent application scope, wherein the active layer is a single quantum well structure formed between the first semiconductor material layer and the second semiconductor material layer, and the active layer The manufacturing material can be any of the following: gallium nitride (GaN), aluminum gallium nitride (Al _x Ga _1-x N), or indium gallium nitride (In _x Ga _1-x N). The micro-luminescent diode according to item 1 of the patent application scope, wherein the active layer is a multiple quantum well structure formed between the first semiconductor material layer and the second semiconductor material layer, and the multiple quantum The well structure can be any of the following: multiple stack structures of gallium nitride and indium gallium nitride (In _x Ga _1-x N), multiple layers of gallium nitride and aluminum gallium nitride (Al _x Ga _1-x N) A stacked structure, or a multiple stacked structure of aluminum gallium nitride (Al _x Ga _1-x N) and indium gallium nitride (In _x Ga _1-x N). The microluminescent diode as described in item 1 of the patent application scope, wherein the manufacturing material of the first electrode and the second electrode may be any one of the following: aluminum (Al), silver (Ag), titanium (Ti ), nickel (Ni), gold (Au), copper (Cu), chromium (Cr), platinum (Pt), a combination of any two of the foregoing, or a combination of any two or more of the foregoing. The micro light emitting diode as described in item 1 of the patent application range, wherein the thickness of the first protective layer and the second protective layer is between 1 nm and 50 nm. The micro light emitting diode as described in item 1 of the patent application scope, wherein the manufacturing material of the first protective layer may be any one of the following: aluminum nitride (AlN), undoped gallium nitride (undoped GaN) ), zinc oxide (ZnO), zinc sulfide (ZnS), or zinc selenide (ZnSe), and the manufacturing material of the second protective layer may be any of the following: aluminum oxide (Al ₂ O ₃ ), hafnium oxide ( HfO ₂ ), magnesium oxide (MgO), zinc oxide (ZnO), or yttrium oxide (Y ₂ O ₃ ). The micro light emitting diode as described in item 1 of the patent application scope, wherein a buffer layer is further included between the second protective layer and the first protective layer. The micro light emitting diode as described in item 9 of the patent application scope, wherein the second protective layer is a first metal oxide layer, and the buffer layer is a second metal oxide layer; and, the buffer The size of an atom of a second metal element of the layer is smaller than the size of an atom of a first metal element constituting the second protective layer. A micro light emitting diode includes: a substrate; a first Bragg reflector formed on the substrate; a first semiconductor material layer formed on the first Bragg reflector; an active layer Is formed on the first semiconductor material layer; a second semiconductor material layer is formed on the active layer; and a second Bragg reflector is formed on the second semiconductor material layer; The first protective layer covers the surface and the side of the second Bragg reflector, the surface and the side of the second semiconductor material layer, the side of the active layer, the side of the first semiconductor material layer, and the first Bragg reflection The side of the mirror has a first opening and a second opening; a second protective layer is formed on the first protective layer, and has a third opening corresponding to the first opening and corresponding to the first opening A fourth opening of the second opening; a first electrode formed on the first semiconductor material layer through the second opening and the fourth opening; and a second electrode through the first opening and The third opening is formed on the second semiconductor material layer; wherein, the refractive index of the first protective layer is smaller than the second semiconductor material layer, and the refractive index of the second protective layer is smaller than the first protective layer . The microluminescent diode as described in item 11 of the patent application scope, wherein the substrate may be any one of the following: spinel substrate, silicon carbide (SiC) substrate, sapphire (Sapphire) substrate, ceramic substrate, Polyimide (Polyimide) substrate, or printed circuit board. The micro-emitting diode as described in item 11 of the patent application scope is a vertical cavity surface emitting laser device (VCSEL device). The microluminescent diode as described in item 11 of the patent application range, wherein the manufacturing material of the first semiconductor material layer is an N-type III-V semiconductor compound, and the manufacturing material of the second semiconductor material layer is P-type III-V semiconductor compound. The microluminescent diode as described in item 11 of the patent application range, wherein the active layer is a single quantum well structure or a multiple quantum formed between the first semiconductor material layer and the second semiconductor material layer Well structure. The micro-emitting diode as described in item 11 of the patent application scope, wherein the manufacturing material of the first electrode and the second electrode may be any one of the following: aluminum (Al), silver (Ag), titanium (Ti ), nickel (Ni), gold (Au), copper (Cu), chromium (Cr), platinum (Pt), a combination of any two of the foregoing, or a combination of any two or more of the foregoing. The micro light emitting diode as described in item 11 of the patent application range, wherein the thickness of the first protective layer and the second protective layer is between 1 nm and 50 nm. The micro light emitting diode as described in item 11 of the patent application scope, wherein the manufacturing material of the first protective layer may be any one of the following: aluminum nitride (AlN), gallium nitride (GaN), zinc sulfide ( ZnS), or zinc selenide (ZnSe), and the manufacturing material of the second protective layer may be any of the following: aluminum oxide (Al ₂ O ₃ ), hafnium oxide (HfO ₂ ), titanium oxide (TiO ₂ ), Yttrium oxide (Y ₂ O ₃ ). The micro light-emitting diode as described in item 11 of the patent application range, wherein a buffer layer is further included between the second protective layer and the first protective layer. The micro light emitting diode as described in Item 19 of the patent application range, wherein the second protective layer is a first metal oxide layer, and the buffer layer is a second metal oxide layer; and, the buffer The size of an atom of a second metal element of the layer is smaller than the size of an atom of a first metal element constituting the second protective layer.

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