TWI396297B - Light emitting diode structure and manufacturing method of the same - Google Patents

Description

Light-emitting diode structure and manufacturing method thereof

The invention relates to a light-emitting diode (LED), in particular to a high luminous efficiency light-emitting diode structure having a photonic crystal structure and a manufacturing method thereof.

Recently, the shortage of energy in the world has led to the continuous rise of oil prices. Countries around the world are not actively investing in the development of energy-saving products. For example, energy-saving bulbs are the product of this trend. With the advancement of light-emitting diode (LED) technology, the application of white light or other color (for example, blue light) light-emitting diodes has gradually developed, including: liquid crystal display (LCD) backlight, printer, for Computer optical connectors (indicators), indicator lights, ground lights, emergency lights, medical equipment light sources, automotive instrumentation and interior lights, auxiliary lighting, main lighting, etc. In short, the light-emitting diode system is currently the main application with backlight and illumination functions. In the lighting market of the next generation, it will be the world of light-emitting diodes. Because the light-emitting diode has the advantages of light weight, power saving and long life, it conforms to the trend of the world. Europe, the United States, Japan and other countries are all invested in the development of the country, and China's LED industry, in the global market, both in research and development and manufacturing have a pivotal role and status. Therefore, in the next generation of development in the field of light-emitting diodes, Taiwan will not be absent.

At present, the application of light-emitting diodes in the white light market has brought the small lighting market to another level. Among them, the backlight of the mobile phone has been replaced by the light-emitting diode. From the early yellow and green light-emitting diodes to the current white or blue light-emitting diodes, the mobile phone has been decorated with colorful colors. As for the personal digital assistant (PDA) and even the backlight of the liquid crystal display panel (TFT-LCD), it will also become the world of light-emitting diodes. Its advantages of light and power saving will make it irreplaceable.

At this stage, there is still a long way to go from the era of white light-emitting diode lighting. If the white light emitting diode is to replace the current lighting market, the luminous efficiency must be at least Achieving above 80 lm / W, this goal will also become one of the goals of national efforts.

In the luminescence mechanism of the light-emitting diode, the luminous efficiency depends on the internal quantum efficiency and the external light extraction efficiency, and the internal quantum luminescence efficiency is mainly controlled by the constituent materials of the light-emitting diode and its crystallinity. In other words, the luminous efficiency of the light-emitting diode is mainly determined by the structure and quality of the epitaxial layer. When a defect exists in the epitaxial layer, the photodiode is absorbed due to defects in the structure. The luminous efficiency of the body will be greatly reduced.

The light formed by the light-emitting layer of the conventional light-emitting diode is reflected by the interface between the P-type semiconductor layer and the transparent conductive layer, so that the light extraction efficiency of the light-emitting diode is affected. In addition, the pattern of increasing the roughened surface or the formation of the photonic crystal structure on the light-emitting surface of the light-emitting diode is directly processed on the semiconductor layer, and the method is easy to cause the light-emitting layer to be damaged or cause damage to the element. In addition, since the sapphire substrate has high hardness and high corrosion resistance, it has a certain degree of difficulty in processing. The general processing method mainly uses a lithography etching process, electron beam or laser processing to form a specific pattern on the sapphire substrate. Limited by the above-mentioned process limitations, it is difficult to obtain a nano-scale pattern and to manufacture a large-area component, and the manufacturing process of the above technology is complicated and the equipment and manufacturing cost are relatively expensive.

Furthermore, since the refractive index between the semiconductor layers of some light-emitting diodes (for example, GaN refractive index n>2.4) and air (refractive index n is approximately 1.0) is large, the critical angle of total reflection is only about 20 ~30 degrees, the light generated by most of the luminescent layer can only be totally reflected inside the component, and can not effectively emit light, so even if the internal luminous efficiency is improved, the external light extraction efficiency can not be improved.

Therefore, based on the above problems, and in response to the trend of demand, it has become an important development direction to improve the light extraction efficiency of the light-emitting diode from the process technology. Therefore, the present invention will provide a light-emitting diode structure having high luminous efficiency and a manufacturing method thereof, which can improve the light extraction efficiency of the light-emitting diode and reduce the epitaxial layer of the light-emitting diode. Crystal defects improve luminous efficiency.

It is an object of the present invention to provide a novel light-emitting diode structure having a porous photonic crystal structure and a method of fabricating the same.

It is still another object of the present invention to provide a light-emitting diode of a photonic crystal structure having (periodic) micron-scale pores.

It is an object of the present invention to provide a light-emitting diode of a photonic crystal structure having (periodic) nano-scale pores.

Another object of the present invention is to construct a photonic crystal structure of micron-order periodic holes on the substrate itself so as to exhibit regular periodic arrangement, which can improve the epitaxial quality and increase the external light extraction efficiency to effectively improve the light emission. The luminous efficiency of the polar body.

Another object of the present invention is to construct a photonic crystal structure of a nano-scale periodic hole on a micron-scale photonic crystal structure so as to exhibit a regular and periodic arrangement, which can improve the epitaxial quality and reduce the epitaxial structure. The defects generated make the electrical properties of the light-emitting diodes better.

It is still another object of the present invention to provide a light-emitting diode that can simplify the process for use in the manufacture of large-area components.

A light emitting diode comprising: a substrate having a first hole therein; a photonic crystal structure (as a buffer layer) formed on the substrate, the photonic crystal structure having a second hole located on at least the substrate and the first hole a first type epitaxial layer formed on the photonic crystal structure; a light emitting layer formed on the first type epitaxial layer; and a second type epitaxial layer formed on the light emitting layer; the first contact An electrode is formed on the first type epitaxial layer; and a second contact electrode is formed on the second type epitaxial layer.

A method of manufacturing a light emitting diode, comprising: firstly, providing a substrate; then, removing a portion of the substrate to form a first hole in the substrate; and then forming a porous photonic crystal structure on the substrate, wherein The photonic crystal structure has a second hole located on at least the substrate and the first hole; subsequently, forming a first type epitaxial layer on the porous photonic crystal structure; and then forming a light emitting layer on the first type Forming a second type of epitaxial layer on the light-emitting layer; then forming a first contact electrode on the first type of epitaxial layer; and then forming a second contact electrode In the second type above On the epitaxial layer.

The substrate is formed by a lithography and etching process to form a first hole in the substrate. The second porous porous photonic crystal structure is a porous aluminum oxide film formed by an anodizing process using a pure aluminum film.

Some embodiments of the invention are described in detail below. However, the present invention may be widely practiced in other embodiments, and the scope of the present invention is not limited to the embodiments described below, which are subject to the scope of the following claims.

Further, in order to provide a clearer description and a better understanding of the present invention, the various parts of the drawings are not drawn according to their relative dimensions, and the irrelevant details are not fully drawn for simplicity of illustration.

The drawings are only intended to illustrate the preferred embodiments of the invention and are not intended to limit the invention. Generally, the lattice defect of the epitaxial layer is reduced by directly processing the surface of the (sapphire) substrate to form a micron- or nano-scale uneven structure.

The invention firstly forms a micro-scale two-dimensional photonic crystal structure having a periodic lattice coefficient in a substrate by using a wet etching process (or dry etching, polishing, electron beam, ion beam, etc.), and the photonic crystal structure can be facilitated. The subsequent process is carried out. Such a structure can not only effectively improve the epitaxial quality, but also increase the internal quantum luminescence efficiency, solve the problem of total light reflection between the substrate and the epitaxial layer, and reduce the lateral light leakage generated along the interface, and the result is effectively improved. The external light extraction efficiency of the light emitting diode.

The invention additionally utilizes anodizing techniques (or electron beam bombardment) to fabricate a two-dimensional photonic crystal structure having a (periodic) nanoscale lattice coefficient on the surface of the first layer structure (eg, AlN, SiO ₂ , Al ₂ O ₃ ). The photonic crystal structure can effectively improve the epitaxial quality and increase the internal quantum luminous efficiency. Furthermore, the nano-scale lattice coefficient can greatly reduce the defects generated during epitaxial growth, and control and reduce the leakage current generated between the substrate and the epitaxial layer, so that the electrical properties of the light-emitting diode are greatly improved.

In one embodiment, the light-emitting phenomenon generated by the porous alumina photonic crystal structure of the present invention is used to increase the light-emitting intensity of the light-emitting diode by adjusting the material of the light-emitting layer such that the light is in the blue light range.

Please refer to the sixth drawing, which is a cross-sectional view of the structure of the light emitting diode according to the present invention. The light emitting diode structure comprises: a substrate 10 having a micron-sized porous photonic crystal structure therein, a nano-scale porous photonic crystal structure 14, a first-type epitaxial layer 15, a light-emitting layer 17, and a second-type epitaxial crystal. Layer 18, first contact electrode 16, and second contact electrode 19. In one embodiment, the material of the substrate 10 may be sapphire, gallium nitride (GaN), aluminum nitride (AlN), tantalum carbide (SiC) or gallium aluminum nitride (GaAlN). The substrate 10 is subjected to a roughening process to roughen the surface of the substrate 10 to form a rough surface. In one embodiment, the surface roughening process forms a micro-scale two-dimensional photonic crystal structure having a periodic lattice coefficient in the substrate 10.

The first figure is a cross-sectional view of the structure of the light-emitting diode substrate of the present invention. A surface of the substrate 10 is formed with a positive photoresist layer 11 as shown in the first figure. After the photoresist layer 11 is subjected to an exposure (lithography process), a photoresist layer 12 having exposed regions and non-exposed regions is formed. The photoresist layer of the exposed regions is the photoresist layer 12a. Please refer to the second figure. Thereafter, the photoresist layer 12a of the exposed region is removed through a developing process, and as a result, the photoresist pattern 13 is formed. Please refer to the third figure. After the photoresist pattern 13 is formed, it can be passed through a hard bake process to facilitate subsequent processes.

Next, using the photoresist pattern 13 as an etching mask, the surface of the substrate 10 is etched by wet etching (or dry etching, polishing, electron beam, ion beam, etc.) to form a substrate 10 having a periodic hole 10a pitch, such as The fourth picture shows. The structural size of the periodic holes 10a is defined by the photoresist pattern 13. For example, the hole 10a has a diameter of about 0.5 to 5 μm, a distance between the holes and the holes (arrangement period) is about 1 to 10 μm, and a hole density is about 10 ⁸ to 10 ¹² holes per square centimeter.

The etching solution for wet etching is, for example, an oxalic acid (C ₂ H ₂ O ₄ ) solution, a phosphoric acid solution or the like. For example, an acidic etching solution has an effect of etching on an alumina substrate, which can produce the following chemical reaction: Al ₂ O ₃ +3H ₂ SO ₄ → 2Al(SO ₄ ) ₃ +3H ₂ O

Al ₂ O ₃ +2H ₃ PO ₄ → 2AlPO ₄ +3H ₂ O

In one embodiment, the substrate etching process can be performed by heating in an 80% phosphoric acid solution, 5% nitric acid, 5% acetic acid, and 20% pure water to a temperature of 35 to 45 degrees Celsius. As the immersion time of the heat treatment changes, the pores of the alumina substrate periodically expand, and the erosion rate is about 1000 to 3000 angstroms per liter (A/min). In another embodiment, the above-mentioned base etching process may be in a 3:1 acidic solution, and the solution composition thereof includes a sulfuric acid (H ₂ SO ₄ ) solution (the ratio of which is 3) and phosphoric acid (H ₃ PO ₄ ). The solution (in a ratio of 1) is heated to a temperature of 200 to 400 degrees Celsius. As the immersion time of the heat treatment changes, the pores of the alumina substrate periodically expand until a certain size.

Next, after etching the substrate 10, a thin layer of epitaxial crystal of cerium oxide (SiO ₂ ) is deposited, which is deposited, for example, by vapor deposition (E-GUN), sputtering (sputter), and plasma chemical vapor deposition ( PECVD), chemical vapor deposition (CVD), physical vapor deposition (PVD), hot dip plating. After epitaxial growth of deposited cerium oxide (SiO ₂ ), a thin layer of cerium oxide crystal is grown on the substrate, which serves as a buffer layer necessary for subsequent periodic holes.

Subsequently, a metal thin film is formed on the substrate 10 by a deposition deposition technique (for example, evaporation, sputtering, plasma chemical vapor deposition, chemical vapor deposition, physical vapor deposition, hot dip plating), and the holes are filled. 10a. In one embodiment, the metal film is an aluminum metal film having a film thickness of 0.5 to 2.0 microns.

Then, a periodic nano-sized porous oxidized metal thin film pattern 14 is formed on the surface of the substrate 10 and the hole 10a by an anodization technique, please refer to the fifth drawing. For example, the porous oxidized metal thin film pattern 14 includes a plurality of holes formed on the substrate 10. For example, the depth of the hole 14b formed over the area of the hole 10a is greater than the depth of the hole 14a formed above the non-hole area.

For example, the anode treatment of the above pure aluminum film is carried out in an environment of 0.2 to 0.5 molar concentration (M) of oxalic acid (C ₂ H ₂ O ₄ ), plus a direct current voltage of 20 to 50 volts. As the time of the anode treatment changes, the thickness of the porous alumina film gradually increases. For example, the pore diameter of the alumina film is about 5 to 400 nm (preferably 30 to 80 nm), between the pores and the pores. The distance (arrangement period) is about 80 to 120 nm, and the hole density is about 10 ⁸ to 10 ¹² holes per square centimeter.

In general, an anodized metal film exhibits a cellular tube structure. The process of forming such a structure is detailed as follows: at the beginning of energization, some parts of the surface of the aluminum anode start to dissolve, and as time increases, the amount of aluminum dissolved increases, and the surface of the anode begins to exhibit uneven roughness, and the time continues to increase. Due to unevenness, the dissolution rate varies. The faster dissolved portion gradually sag, and the dissolved aluminum ions gradually form aluminum hydroxide and alumina deposited on the surface, but there are still pores for the dissolution reaction to continue, and after a period of time, the deposited precipitate forms the tube wall, and the tube The main component of the wall contains water-alumina or colloidal aluminum hydroxide. The closer the water content is to the center of the tube wall, the closer it is to pure alumina, and the area close to the electrolyte is the area where aluminum is dissolved and deposited. The longer the deposition, the denser it is. .

When anodizing with an acidic solution, the acidic electrolyte decomposes the surface of the pure aluminum metal and begins to grow the oxide layer. Decomposition of pure aluminum metal surface causes the formation of fine pores. At the same time, a barrier layer is formed at the bottom of the hole to isolate the oxide layer from the metal aluminum. When the pore formation tends to be stable, it will start to grow at a certain rate to form a honeycomb structure similar to honeycomb structure. Floor.

The operating voltage during anode processing affects the pores, pore spacing and cell size, and the relationship between them is directly proportional. In other words, the larger the applied voltage, the larger the hole, the hole pitch and the cell.

Theoretically, the pores of the anodized aluminum film can be regularly arranged, but usually the range does not exceed a few microns. At the beginning of the formation of the voids, the disordered pore formation will cause the pores on the front side of the anodized aluminum film to be irregular, and when the pore formation is stable, the regular pore arrangement can be seen on the back side of the template. In order to obtain a wide range of regular holes, two methods such as two-step anodization or pre-pattern on the surface of the aluminum metal layer may be used.

The electrolyte used for the anodizing of the aluminum metal may include a plurality of kinds of electrolytes, each of which has a different main chemical composition, and the pore structure is different depending on the structure of the film after the treatment. For example, the electrolyte includes: (1) sulfuric acid liquid, for example, 15 to 20% sulfuric acid, operating voltage is 14 to 22 volts, current density is 1 to 2 A/dm ² , ambient temperature is 18 to 25 ° C, and processing time is 10 ~60 minutes, it can form a film thickness of 3 ~ 35 microns. The film obtained by the sulfuric acid solution process has good corrosion resistance and good anti-wear property. If the operating temperature is lowered to below 5 ° C, the sulfuric acid concentration is reduced to about 7%, and the treatment voltage is increased to 23 to 120 volts, which can be used for a long time. Processing to obtain a relatively hard anode film having a thickness of 200 μm or more; (2) chromic acid solution, for example, including 5 to 10% chromic acid, operating voltage of 40 volts, current density of 0.15 to 0.30 A/dm ² , ambient temperature of 35 ° C The treatment time is 30 minutes, which can form a film thickness of about 2 to 3 microns, and the film obtained by the chromic acid solution process also has good corrosion resistance; (3) the oxalic acid solution, for example, contains 0.3 mole or 3 to 5 wt% of oxalic acid. (C ₂ H ₂ O ₄ ), voltage is 40~60 volts, current density is 1~2A/dm ² , ambient temperature is 18~20°C, processing time is 40~60 minutes, and it can form a film thickness of about 10~65 Micron, in addition, when the ambient temperature drops to 3~5 °C, a film with a thickness of 625 microns can be obtained after long-term treatment; (4) Phosphoric acid solution, for example, containing 10% phosphoric acid, voltage of 10-12 volts, ambient temperature 23~25 °C, treatment time 20~30 minutes, it can form a film thickness of about 1~2 microns, phosphoric acid solution Larger pores of the film.

The composition of the above four electrolytes and the operating conditions thereof are merely examples of the invention, and are not intended to limit the invention. When the film is formed in the four electrolytes, there is actually a certain pore, which allows the aluminum metal to be continuously eluted to form a film, and the film has a certain solubility, so that the film can continue to grow until the dissolution rate and the growth rate are equal. Further, it is an electrolyte such as boric acid solution, tartaric acid solution, etc., which produces a film which is denser and does not easily allow the aluminum metal to be dissolved by electrolysis, and is therefore suitable for use in forming a thin film.

In one embodiment, the porous oxidized metal film is, for example, a porous alumina film. Then, through a heat treatment process, it can be performed by using a cerium oxide furnace tube, the vacuum is increased in the furnace tube to a vacuum of 1 to 10-3 torr, and the treatment temperature is performed at 500 to 1100 degrees Celsius for 4 hours. After the completion of the heat treatment process, after the growth of the alumina (Al ₂ O ₃ ) crystal is completed, the aluminum oxide polycrystalline state epitaxial crystal is formed on the aluminum oxide thin film pattern 14 and can serve as a buffer layer for the periodic pores.

Further, the light-emitting diode of the present invention comprises an N-type semiconductor layer 15 formed on the substrate 10 and the porous oxidized metal film 14. The N-type semiconductor epitaxial layer 15 can be formed by chemical vapor deposition (CVD) or organometallic chemical vapor deposition (MOCVD). Further, a light-emitting layer 17 is formed on the N-type semiconductor layer 15. The light-emitting layer 17 is an active layer, which may be formed by stacking a plurality of well layers and a plurality of barrier layers. A P-type semiconductor epitaxial layer 18 is formed on the light-emitting layer 17, and similarly, the P-type semiconductor layer 18 can be formed by chemical vapor deposition or metalorganic chemical vapor deposition (MOCVD). The material of the P-type semiconductor layer 18 or the N-type semiconductor layer 15 may be selected from one of gallium nitride (GaN), indium gallium nitride (IrGaN), gallium nitride-based or nitride-based semiconductor epitaxial.

The second contact electrode 19 is formed on the surface of the P-type semiconductor layer 18, and is used for As a P-type contact or N-type contact. Further, a first contact electrode 16 is formed on the N-type semiconductor layer 15 for use as an N-type contact or a P-type contact. The above two contact electrodes may be made of titanium/aluminum (TiAl), titanium/aluminum/titanium/gold (Ti/Al/Ti/Au), and titanium/aluminum/nickel/gold (Ti/Al/Ni/Au). One of the alloys.

In addition, the present invention also provides a method of manufacturing a light-emitting diode, the main steps of which include: first, providing a substrate 10. Next, a photoresist layer 12 is formed on the substrate 10, and the substrate 10 is patterned by a lithography and etching process to obtain a hole pattern 10a. Subsequently, a metal thin film is formed on the substrate 10 and filled in the hole 10a. Next, an anode treatment process is performed on the metal thin film to form a nanoporous porous metal oxide film pore structure 14, which is the porous photonic crystal structure of the present invention. In one embodiment, the material of the substrate 10 includes sapphire, gallium nitride (GaN), aluminum nitride (AlN), tantalum carbide (SiC) or aluminum gallium nitride (GaAlN).

Then, an N-type semiconductor layer 15 is formed over the porous photonic crystal structure 14. Thereafter, the light-emitting layer 17 is formed on the above-described N-type semiconductor layer 15. The light-emitting layer 17 is an active layer, which may be formed by stacking a plurality of well layers and a plurality of barrier layers. Next, a P-type semiconductor layer 18 is formed over the light-emitting layer 17.

Then, a first contact electrode 16 is formed on the surface of the N-type semiconductor layer 15, which is used as an N-type contact electrode. Thereafter, a second contact electrode 19 is formed on the P-type semiconductor layer 18, which serves as a P-type contact electrode. The above two electrodes may be made of titanium nitride, titanium/aluminum (TiAl), titanium/aluminum/titanium/gold (Ti/Al/Ti/Au), and titanium/aluminum/nickel/gold (Ti/Al/Ni). /Au) One of the alloys.

By utilizing the characteristics of the above porous alumina film, the light-emitting path formed by the light-emitting layer 17 reduces the reflectance between the interface of the N-type semiconductor layer 15 and the substrate 10, so that most of the excited light can be radiated to the outside of the element. As a result, the light extraction efficiency of the light-emitting diode of the present invention is improved. In addition, the photonic crystal structure can also effectively improve the epitaxial quality and increase the internal quantum luminous efficiency.

The main advantages of the invention are as follows:

1. Using a wet etching process on a (sapphire) substrate to form a periodic regular arrangement The effect of the hole can greatly improve the external light extraction efficiency, and can improve the internal luminous efficiency of the light-emitting diode, and at the same time, the process can be simplified and the damage caused by the processing can be avoided.

2. Using the anodizing process to achieve the surface roughening effect on the (sapphire) substrate, in addition to effectively improving the internal luminous efficiency, it can also reduce the defects generated during epitaxial growth and avoid the interface and the epitaxial layer. The leakage current causes damage to the light-emitting diode.

3. Using the photonic crystal effect, the epitaxial quality and the lateral light leakage problem can be effectively improved, and the periodic irregular shape of the structure itself can also reduce the total reflection between the substrate and the epitaxial layer, and increase the light extraction efficiency.

4. The photon crystal itself has photoexcitation characteristics, which can increase the luminous intensity of the light-emitting diode.

5. The process of the present invention is simple and suitable for use in the manufacture of large area components.

The present invention has been described above by way of a preferred embodiment, and is not intended to limit the scope of the claimed invention. The scope of patent protection is subject to the scope of the patent application and its equivalent fields. Any modification or refinement made by those skilled in the art without departing from the spirit or scope of the present invention is equivalent to the equivalent change or design made in the spirit of the present disclosure, and should be included in the following patent application scope. Inside.

10‧‧‧Substrate

10a‧‧‧ hole

11‧‧‧Photoresist layer

12‧‧‧Photoreceptor layer after exposure

12a‧‧‧Photoresist layer in the exposed area

13‧‧‧resist pattern

14‧‧‧Porous oxidized metal film

14a, 14b‧‧‧ holes

15‧‧‧N type semiconductor layer

16‧‧‧First contact electrode

17‧‧‧Lighting layer

18‧‧‧P type semiconductor layer

19‧‧‧Second contact electrode

The above and many advantages of the invention will be readily apparent from the following detailed description in conjunction with the accompanying drawings in which: FIG. 1 is a cross-sectional view of a photoresist layer formed on a substrate in accordance with the present invention.

The second figure is a cross-sectional view of the exposure to the photoresist in accordance with the present invention.

The third figure is a cross-sectional view of a photoresist pattern formed on a substrate in accordance with the present invention.

The fourth figure is a cross-sectional view of a patterned substrate in accordance with the present invention.

Figure 5 is a cross-sectional view of a nanoscale porous photonic crystal structure formed on a patterned substrate in accordance with the present invention.

Figure 6 is a cross-sectional view of a light-emitting diode having a nano-scale porous photonic crystal structure according to the present invention.

10‧‧‧Substrate

14‧‧‧Porous oxidized metal film

15‧‧‧N type semiconductor layer

16‧‧‧First contact electrode

17‧‧‧Lighting layer

18‧‧‧P type semiconductor layer

19‧‧‧Second contact electrode

Claims (33)

A light-emitting diode comprising: a substrate having a plurality of first holes therein, the first holes being periodically arranged; a photonic crystal structure formed on and in contact with the substrate, the photonic crystal structure including porosity An aluminum oxide film having a plurality of second holes, the second holes being periodically arranged and located on at least the substrate and the first hole; the first type of epitaxial layer formed on The photonic crystal structure is overlaid and covered; the luminescent layer is formed on the first type epitaxial layer; the second epitaxial layer is formed on the luminescent layer; and the first contact electrode is formed on the first a type of epitaxial layer; and a second contact electrode formed over the second type of epitaxial layer. The light-emitting diode of claim 1, wherein the material of the substrate comprises sapphire, gallium nitride (GaN), aluminum nitride (AlN), tantalum carbide (SiC) or gallium nitride aluminum (GaAlN). ). The light-emitting diode of claim 1, wherein the first hole has a size of 0.5 to 5 micrometers. The light-emitting diode of claim 1, wherein the first hole has an arrangement period of 1 to 10 μm. For example, in the light-emitting diode of the first application of the patent scope, the first hole has a hole density of 10 ⁸ to 10 ¹² holes per square centimeter. The light-emitting diode of claim 1, wherein the photonic crystal structure has a thickness of 0.5 to 2.0 μm. For example, in the light-emitting diode of claim 1, wherein the second hole has a size of 5 to 400 nm. For example, in the light-emitting diode of claim 1, wherein the second hole has an arrangement period of 80 to 120 nm. For example, in the light-emitting diode of claim 1, wherein the second hole has a hole density of 10 ⁸ to 10 ¹² holes per square centimeter. The light-emitting diode of claim 1, wherein the porous alumina film is formed by anodizing a pure aluminum film. The light-emitting diode of claim 10, wherein the pure aluminum film is formed by vapor deposition, sputtering, hot dip plating, or plasma chemical vapor deposition. The light-emitting diode of claim 10, wherein the anode-treated electrolyte comprises a sulfuric acid solution, a chromic acid solution, an oxalic acid solution, a phosphoric acid solution, a boric acid solution or a tartaric acid solution or a combination solution thereof. The light-emitting diode of claim 1, wherein the photonic crystal structure is formed by anodization. The light-emitting diode of claim 1, wherein the material of the first type epitaxial layer may be selected from the group consisting of gallium nitride (GaN), indium gallium nitride (InGaN), gallium nitride or nitrogen-based semiconductor. One of the crystals. The light-emitting diode of claim 1, wherein the material of the second type epitaxial layer may be selected from the group consisting of gallium nitride (GaN), indium gallium nitride (InGaN), gallium nitride, or nitrogen-based semiconductor. One of the crystals. The light-emitting diode of claim 1, wherein the first type of epitaxial layer is N-type and the second type of epitaxial layer is P-type, or the first-type epitaxial layer is P-type and the first The type II epitaxial layer is N type. A method for manufacturing a light emitting diode, comprising: providing a substrate; removing a portion of the substrate to form a plurality of first holes periodically arranged in the substrate; forming a photonic crystal structure on the substrate by using an anodizing technique And in contact with, the photonic crystal structure comprises a porous alumina film, wherein the porous alumina film has a plurality of second holes periodically arranged on at least the substrate and the first hole; forming a first type An epitaxial layer is over the photonic crystal structure and covered; a light emitting layer is formed on the first type epitaxial layer; and a second type epitaxial layer is formed on the light emitting layer; forming a first contact An electrode is over the first type epitaxial layer; and a second contact electrode is formed over the second type epitaxial layer. The method for manufacturing a light-emitting diode according to claim 17, wherein the material of the substrate comprises sapphire, gallium nitride (GaN), aluminum nitride (AlN), tantalum carbide (SiC) or gallium nitride. Aluminum (GaAlN). The method for manufacturing a light-emitting diode according to claim 17, wherein the first hole has a size of 0.5 to 5 μm. The method for manufacturing a light-emitting diode according to claim 17, wherein the first hole has an arrangement period of 1 to 10 μm. The method for manufacturing a light-emitting diode according to claim 17, wherein the first hole has a hole density of 10 ⁸ to 10 ¹² holes per square centimeter. The method for manufacturing a light-emitting diode according to claim 17, wherein the photonic crystal structure has a thickness of 0.5 to 2.0 μm. The method for manufacturing a light-emitting diode according to claim 17, wherein the second hole has a size of 5 to 400 nm. The method for manufacturing a light-emitting diode according to claim 17, wherein the second hole has an arrangement period of 80 to 120 nm. The method for manufacturing a light-emitting diode according to claim 17, wherein the second hole has a hole density of 10 ⁸ to 10 ¹² holes per square centimeter. The method for producing a light-emitting diode according to claim 17, wherein the porous alumina film is formed by subjecting a pure aluminum film to an anodizing process. The method for producing a light-emitting diode according to claim 26, wherein the pure aluminum film is formed by a method of vapor deposition, sputtering, hot dip plating, or plasma chemical vapor deposition. The method for producing a light-emitting diode according to claim 26, wherein the anode-treated electrolyte comprises a sulfuric acid solution, a chromic acid solution, an oxalic acid solution, a phosphoric acid solution, a boric acid solution or a tartaric acid solution or a combination thereof. The method for manufacturing a light-emitting diode according to claim 17, wherein the first hole is formed by a lithography and etching process. The method of manufacturing a light-emitting diode according to claim 17, wherein the photonic crystal structure is formed by anodization. The method for manufacturing a light-emitting diode according to claim 17, wherein the material of the first type epitaxial layer may be selected from the group consisting of gallium nitride (GaN), indium gallium nitride (InGaN), gallium nitride or nitrogen. One of the base semiconductor epitaxes. The method for manufacturing a light-emitting diode according to claim 17, wherein the material of the second type epitaxial layer may be selected from the group consisting of gallium nitride (GaN), indium gallium nitride (InGaN), gallium nitride or nitrogen. One of the base semiconductor epitaxes. The method for manufacturing a light-emitting diode according to claim 17, wherein the first type of epitaxial layer is an N-type semiconductor layer and the second type of epitaxial layer is a P-type semiconductor layer, or the first type of epitaxial layer The layer is a P-type semiconductor layer and the second type epitaxial layer is an N-type semiconductor layer.