Light-emitting diode package module

Abstract

This invention provides an optical diode package module having a resonant cavity structure. [Solution] The light-emitting diode package module comprises a carrier unit having a substrate and a plurality of electrical connection units, and a plurality of light-emitting diodes 3 connected in a flip-chip format. Each light-emitting diode 3 has a reflective unit 31 having a first reflective layer 311 and a second reflective layer 312, a light-emitting unit 32 having an n-type gallium nitride epitaxial layer 321 and a p-type gallium nitride epitaxial layer 323 stacked sequentially from the surface of the first reflective layer 311, an insulating layer 33, and an electrode unit 34. Each light-emitting diode 3 is connected to the electrical connection unit via a first extended electrode portion 343 and a second extended electrode portion 344 of the electrode unit 34.

Description

[Technical Field]

[0001] This invention relates to semiconductor package modules, and more particularly to light-emitting diode package modules. [Background technology]

[0002] In modern society, the internet is essential, and the demands for internet transmission speed and quality are increasing. While traditional copper wires were used as the signal transmission medium, optical fiber transmission is now becoming widespread. When using optical fiber as a medium, it is usually used for long-distance data transmission, but for short-distance transmission, that is, for information transmission between optical elements and electronic elements, the conversion between photons and electrons must be performed in a short time, so the demands for precision and instantaneous startup are also increasing.

[0003] Micro-resonator light-emitting diodes (LEDs) offer advantages such as high brightness and high response. Furthermore, their unique resonator structure allows only light of specific wavelengths to pass through, resulting in higher luminous efficiency and a narrower emission wavelength range compared to conventional LEDs.

[0004] However, since the light emitted by resonant cavity light-emitting diodes (LEDs) is non-directional and their volume is small, practical applications require the use of multiple micro-resonant cavity LEDs in combination. Therefore, research to improve the light emission directionality and light intensity of micro-resonant cavity LEDs to make them suitable for applications in the field of short-distance optical communication is currently attracting attention. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] U.S. Patent Application Publication No. 2019 / 0348588A1 [Overview of the project] [Problems that the invention aims to solve]

[0006] In view of the above problems, the object of the present invention is to provide a light-emitting diode package module having a resonant cavity structure. [Means for solving the problem]

[0007] To achieve the above objective, the present invention provides a light-emitting diode package module comprising a carrier unit and a plurality of light-emitting diodes, wherein the carrier unit comprises a substrate and a plurality of electrical connection units, the substrate having a top surface and a bottom surface facing opposite directions, and a plurality of regularly arranged through holes penetrating from the bottom surface to the top surface, each electrical connection unit comprising two electrical connection portions respectively disposed within the two through holes so as to extend from the bottom surface to the top surface, a first electrical connection member disposed on the top surface side to connect to one of the two electrical connection portions, and a second electrical connection member disposed on the top surface side to connect to the other of the two electrical connection portions, the plurality of light-emitting diodes are connected to the corresponding electrical connection units in a flip-chip configuration, each light-emitting diode comprising a reflective unit, a light-emitting unit, an insulating layer, and an electrode unit, the reflective unit having a first reflective layer in which n-type gallium nitride layers having different refractive indices are laminated, The light-emitting unit comprises an n-type gallium nitride epitaxial layer, a quantum well layer, and a p-type gallium nitride epitaxial layer, which are sequentially stacked from the surface of the first reflective layer, and the electrode unit comprises a first electrode portion located on the surface of the n-type gallium nitride epitaxial layer and a current diffusion layer electrically connected to the portion of the surface of the p-type gallium nitride epitaxial layer opposite to the quantum well layer. The p-type gallium nitride epitaxial layer has a current-limiting zone to which the current-diffusing layer is connected. The present invention provides a light-emitting diode package module characterized in that the insulating layer covers the surfaces of the light-emitting unit, the first electrode portion, and the current diffusion layer, the electrode unit further has a first stretched electrode portion and a second stretched electrode portion that penetrate the insulating layer and are electrically connected to the first electrode portion and the current diffusion layer, respectively, the second stretched electrode portion is located outside the orthographic projection range of the current limiting zone, a gap exists between the first stretched electrode portion and the second stretched electrode portion, the orthographic projection range of the gap covers at least the entire current limiting zone, each light-emitting diode is connected to the corresponding electrical connection unit via the first stretched electrode portion and the second stretched electrode portion, and the reflective unit further has a second reflective layer located between the first stretched electrode portion and the second stretched electrode portion, the reflectivity of the second reflective layer is greater than that of the first reflective layer, and the current limiting zone is located within the orthographic projection range of the second reflective layer. [Effects of the Invention]

[0008] The effect of the present invention is that by designing a carrier unit equipped with multiple electrical connection units, multiple light-emitting diodes can be mounted, and by configuring the carrier unit, the position in which the light-emitting diodes are connected to an external power supply can be rearranged. Furthermore, by configuring each light-emitting diode to have first and second reflective layers and a current-limiting zone, the light intensity of the light-emitting diode can be improved and the range from which light is emitted can be limited, resulting in a light-emitting diode with a small light emission range, high directional light emission intensity. [Brief explanation of the drawing]

[0009] [Figure 1] This is a side view showing the configuration of a first embodiment of the light-emitting diode package module of the present invention. [Figure 2] This is a cross-sectional view showing the detailed structure of the light-emitting diode of the first embodiment. [Figure 3] This is an SEM image showing the structure of the first reflective layer in the first embodiment. [Figure 4] FIG. 4a is a reflectance curve diagram showing the influence of a first reflective layer composed of first and second n-type gallium nitride layers having different thicknesses on reflectance, and FIG. 4b is a reflectance curve diagram showing the influence of the refractive index of the second n-type gallium nitride layer on reflectance. [Figure 5] It is a flowchart showing the manufacturing method of the first embodiment. [Figure 6] It is a flowchart showing the manufacturing method of the first embodiment. [Figure 7] It is a flowchart showing the manufacturing method of the first embodiment. [Figure 8] It is a cross-sectional view showing the detailed structure of the light-emitting diode of the second embodiment of the light-emitting diode package module of the present invention. [Figure 9] FIGS. 9a and 9b are side cross-sectional views showing the detailed structure of the light-emitting diodes of the third and fourth embodiments of the light-emitting diode package module of the present invention. [Figure 10] FIGS. 10a and 10b are side cross-sectional views showing the detailed structure of the light-emitting diodes of the fifth and sixth embodiments of the light-emitting diode package module of the present invention. [Figure 11] FIGS. 11a and 11b are cross-sectional views showing the detailed structure of the light-emitting diodes of the seventh and eighth embodiments of the light-emitting diode package module of the present invention. [Figure 12] FIG. 12a is a light intensity curve diagram showing the light emission range of the third embodiment of the present invention and a comparative example, and FIG. 12b is a light intensity curve diagram showing the light emission characteristics at a small angle of the third embodiment and the comparative example.

MODE FOR CARRYING OUT THE INVENTION

[0010] To more clearly explain the objectives, technical means, and advantages of the embodiments of the present invention, hereinafter, in combination with the accompanying drawings of the embodiments of the present invention, the technical means in the embodiments of the present invention will be clearly and detailedly described. It will be clear that the embodiments to be described are some of the embodiments of the present invention, not all of the embodiments. Usually, the components of the embodiments of the present invention depicted and shown in the accompanying drawings can be arranged and designed in various different arrangements. Therefore, hereinafter, the detailed description of the embodiments of the present invention provided in the accompanying drawings does not constitute any limitation to the protection scope of the present invention, but only shows the selected embodiments of the present invention.

[0011] Before explaining the present invention in detail, it should be noted that in the following description, elements that perform the same role or function may be represented by the same number even if they do not have exactly the same configuration.

[0012] Also, in this specification, for the convenience of explanation, terms indicating the relative positional relationship of each component, such as "upper", "lower", "left", "right", etc., are used to explain while referring to the examples in the drawings, and it should be noted that they are not absolute terms limiting the configuration of the present invention.

[0013] Also, it should be noted that in the following description, elements that perform the same role or function may be represented by the same number even if they do not have exactly the same configuration. And the content, features, and effects of the related technology of the present invention are clearly shown in the detailed description of the embodiments using the following drawings. Furthermore, it is specified that the drawings of the present invention show the structure and / or positional relationship between components and have nothing to do with the actual dimensions of each component.

[0014] As shown in FIGS. 1 and 2, the first embodiment of the light-emitting diode package module of the present invention has a carrier unit 2 and a plurality of light-emitting diodes 3 electrically connected to the carrier unit 2 in a flip-chip form.

[0015] The carrier unit 2 has a substrate 21 and a plurality of electrical connection units 22. The substrate 21 has a top surface 211 and a bottom surface 212 facing opposite directions, and a plurality of regularly spaced through holes 213 that penetrate from the bottom surface 212 to the top surface 211. Each electrical connection unit 22 has two electrical connection portions 223, each positioned within the two through holes 213 so as to extend from the bottom surface 212 to the top surface 213, a first electrical connection member 221 positioned on the top surface 213 side to connect to one of the two electrical connection portions 223, a second electrical connection member 222 positioned on the top surface 213 side to connect to the other of the two electrical connection portions 223, and two ball-shaped solders 224 connected to the bottom surface 212 side ends of each electrical connection portion 223 on the bottom surface 212.

[0016] Within this, each electrical connection section 223 has a metal column 223a and a seed layer 223b located between the metal column 223a and the substrate 21.

[0017] Each light-emitting diode 3 includes a reflective unit 31, a light-emitting unit 32, an insulating layer 33, and an electrode unit 34.

[0018] The reflective unit 31 has a first reflective layer 311 and a second reflective layer 312 located on opposite sides of the light-emitting unit 32, and the first reflective layer 311 and the second reflective layer 312 are Bragg reflective structures in which a high refractive index n-type gallium nitride layer and a low refractive index n-type gallium nitride layer are alternately stacked.

[0019] The light-emitting unit 32 comprises an n-type gallium nitride epitaxial layer 321, a quantum well layer 322, a p-type gallium nitride epitaxial layer 323, and an oxide layer 324 formed on the p-type gallium nitride epitaxial layer 323, all stacked sequentially from the surface of the first reflective layer 311. The oxide layer 324 is an insulating material, thereby defining a current-limiting zone 323a through which current flows via the p-type gallium nitride epitaxial layer 323. Furthermore, the light-emitting unit 32 of the present invention has a sloping side surface that gradually widens from the surface of the p-type gallium nitride epitaxial layer 323 toward the quantum well layer 322, and the angle between this sloping side surface and the surface of the p-type gallium nitride epitaxial layer 323 is 150 degrees or more. In this first embodiment, this angle is described as 150 degrees. However, in the present invention, the light-emitting unit 32 does not need to have a sloping side surface, and is therefore not limited to the configuration shown in this first embodiment.

[0020] The electrode unit 34 includes a first electrode portion 341 located on the surface of the n-type gallium nitride epitaxial layer 321, a current diffusion layer 340 connected to the surface of the p-type gallium nitride epitaxial layer 323 opposite to the quantum well layer 322, which is translucent and in contact with the current limiting zone 323a, and a first stretched electrode portion 343 and a second stretched electrode portion 344 electrically connected to the first electrode portion 341 and the current diffusion layer 340, respectively. The insulating layer 33 has an outer surface 331 that covers the light-emitting unit 32 and the surface of the first electrode portion 341 and the current diffusion layer 340, and is located above the p-type gallium nitride epitaxial layer 323. The first stretched electrode portion 343 and the second stretched electrode portion 344 extend through the insulating layer 33 to the outer surface 331, and the surfaces of the first stretched electrode portion 343 and the second stretched electrode portion 344 that are connected to the electrical connection unit 22 are located on the same plane. Within this structure, a gap exists between the first extended electrode portion 343 and the second extended electrode portion 344 located on the outer surface 331 of the insulating layer 33. The current limiting zone 323a is located within the orthographic projection range of this gap, meaning that the orthographic projection range of this gap completely covers at least the current limiting zone 323a. The second extended electrode portion 344 is located outside the orthographic projection range of the current limiting zone 323a. Each light-emitting diode 3 has its first extended electrode portion 343 and second extended electrode portion 344 connected to the first electrical connection member 221 and the second electrical connection member 222 of the corresponding electrical connection unit 22, respectively.

[0021] The second reflective layer 312 is connected to the outer surface 331 of the insulating layer 33, located between the first extended electrode portion 343 and the second extended electrode portion 344, and both ends are connected to the first extended electrode portion 343 and the second extended electrode portion 344, respectively. Furthermore, the orthographic projection range of the second reflective layer 312 is greater than or equal to the current limiting zone 323a, and the reflectivity is in the range of 95% to 99.9%, with the reflectivity of the second reflective layer 312 being greater than the reflectivity of the first reflective layer 311.

[0022] Here, the first reflective layer 311 and the second reflective layer 312 can be obtained by stacking a gallium nitride layer with a different high refractive index and a gallium nitride layer with a different low refractive index. As for the gallium nitride layer, by controlling the concentration of dopant ions such as silicon (Si) and tin (Sn), for example, a gallium nitride layer with a different high refractive index or a gallium nitride layer with a different low refractive index can be obtained. In this embodiment, an example is described in which the constituent material of the second reflective layer 312 is the same as that of the first reflective layer 311 and silicon (Si) is used as the dopant ion, but it is not limited to this.

[0023] More specifically, as shown in Figure 3, the first reflective layer 311 is formed by alternately stacking a first n-type gallium nitride layer 311a with a high refractive index and a second n-type gallium nitride layer 311b with a low refractive index. Multiple pyramidal etching holes 311c are formed in the second n-type gallium nitride layer 311b of the first reflective layer 311, as shown in Figure 3.

[0024] In some embodiments, the first reflective layer 311 and the second reflective layer 312 can also use tin (Sn) as the doping ion. When the doping ion is tin (Sn), the doping concentration of the first n-type gallium nitride layer 311a of the first reflective layer 311 is 10 18 ~3×10 18 cm -3 It is within the range, and the doping concentration of the second n-type gallium nitride layer 311b is 10 19 ~5×10 19 cm -3 It is within the range.

[0025] As shown in Figure 4, Figure 4a shows the reflectance results for the first reflective layer 311 obtained by stacking refractive index material layers of different numbers of pairs (each pair having one first n-type gallium nitride layer 311a and one second n-type gallium nitride layer 311b), and Figure 4b shows the reflectance results for the second n-type gallium nitride layer 311b, which similarly has 5 stacked pairs but with different refractive indices.

[0026] From FIG. 4a, it can be seen that the more the number of stacked pairs, the better the reflection effect of the first reflective layer 311 is. Also, from FIG. 4b, when the number of stacked pairs is the same, it can be seen that the smaller the refractive index of the second n-type gallium nitride layer 311b, the larger the difference from the refractive index of the first n-type gallium nitride layer 311a, and the better the reflection effect of the first reflective layer 311 is. In actual implementation, according to different performance requirements, the number of stacked pairs can be selected, and the refractive indices of the first n-type gallium nitride layer 311a and the second n-type gallium nitride layer 311b can be adjusted.

[0027] In this embodiment, the doping concentration of the first n-type gallium nitride layer 311a is 10 17 cm -3 ~10 18 cm -3 within the range, and the doping concentration of the second n-type gallium nitride layer 311b is 10 19 cm -3 ~5×10[[ID=:17]] 19 cm -3 within the range. The refractive index of each first n-type gallium nitride layer 311a is 2.4, the thickness is 53.12 nm, the refractive index of each second n-type gallium nitride layer 311b is 1.7, and the thickness is 75 nm. The first reflective layer 311 is composed of 5 pairs of the first n-type gallium nitride layer 311a and the second n-type gallium nitride layer 311b, and the overall thickness is about 640 nm, but it is not limited thereto.

[0028] In some embodiments, the width of the current limiting zone 323a is within the range of 5 μm to 30 μm.

[0029] In some embodiments, the transmittance of the current diffusion layer 340 is greater than 80%.

[0030] In some embodiments, the ratio of the orthographic projection area of the second reflective layer 312 to the orthographic projection area of the current limiting zone 323a is within the range of 1.5 to 2.

[0031] In some embodiments, the reflectivity of the first reflective layer 311 is within the range of 80% to 95%.

[0032] In some embodiments, the Bragg reflection structure of the second reflection layer 312 may be an alternating layered structure of titanium dioxide (TiO2) / silicon dioxide (SiO2).

[0033] Furthermore, the second reflective layer 312 may be a non-conductive cladding structure instead of a Bragg reflective structure. This non-conductive cladding structure comprises a translucent insulator and a metal cladding layer covered with this insulator, the metal cladding layer being made of aluminum or silver, and light reflection can be achieved even when using the metal cladding layer.

[0034] In some examples, the thickness of the metal cladding layer is greater than 1000 Å.

[0035] Furthermore, in the first embodiment, it is not necessary to form etching holes 311c in the second n-type gallium nitride layer 311b if necessary.

[0036] The manufacturing method of the first embodiment of the present invention will be described below.

[0037] As shown in Figures 5 to 7, first in step a, a sapphire substrate 80 is provided on which a sacrificial layer 81 composed of undoped gallium nitride is formed on the surface. A composite gallium nitride layer 91 is formed by alternately stacking a first n-type gallium nitride layer 311a with a high refractive index and a second n-type gallium nitride layer 311b with a low refractive index, an n-type gallium nitride epitaxial layer 321, a quantum well layer 322, and a p-type gallium nitride epitaxial layer 323 are sequentially deposited on the surface of the sacrificial layer 81 to form the structure shown in Figure 5(a).

[0038] Next, in step b, etching is performed on a portion of the surface of the p-type gallium nitride epitaxial layer 323 until the n-type gallium nitride epitaxial layer 321 is exposed, forming a platform area 400 defined by the first etching groove T1, and creating the structure shown in Figure 5(b). The outside of this platform area 400 has a sloping side surface whose width gradually increases from the p-type gallium nitride epitaxial layer 323 toward the quantum well layer 322, and the angle between this sloping side surface and the adjacent surface of the p-type gallium nitride epitaxial layer 323 is 150 degrees.

[0039] Next, in step c, a resist layer 500 is formed that completely covers the surface of the platform area 400, as shown in Figure 5(c).

[0040] Next, in step d, as shown in Figure 5(d), the n-type gallium nitride epitaxial layer 321 that is not covered by the resist layer 500 of the first etching groove T1 is etched to form a second etching groove T2 in which the sapphire substrate 80 is exposed to the outside, and the resist layer 500 is removed to form a first semi-finished product 600 having a platform area 400.

[0041] Next, in step e, silicon dioxide is deposited on the surface of the first semi-finished product 600 until the surface of the first semi-finished product 600 is completely covered to form a silicon dioxide layer S.

[0042] Next, in step f, etching is performed on the surface of the silicon dioxide layer S to remove the silicon dioxide layer S located in the first etching groove T1 and the second etching groove T2, and the composite gallium nitride layer 91 located on one side of the second etching groove T2 of the first semi-finished product 600 is exposed by etching control.

[0043] Next, in step g, electrochemical etching is performed on the first semi-finished product 600 while it is exposed to an acidic (nitric acid) environment, and the etching reaction is accelerated by ultraviolet irradiation, thereby electrochemically etching one side of the composite gallium nitride layer 91 that is exposed to the second etching groove T2, forming a plurality of etching holes 311c on one side of the second n-type gallium nitride layer 311b that is close to the second etching groove T2, and forming the first reflective layer 311 having etching holes 311c. After that, the silicon dioxide layer S is removed to obtain the second semi-finished product 700 as shown in Figure 6(g). The crystal structure of gallium nitride is a hexagonal wurtzite type structure, and since the etching rates of the Ga plane and N plane are different, pyramidal etching holes 311c can be etched and formed along the N-plane crystal structure of the second n-type gallium nitride layer 311b by electrochemical etching. Here, by using ultraviolet irradiation as an auxiliary treatment, electron-hole pairings are more easily formed in the second n-type gallium nitride layer 311b with a low refractive index. These holes then help oxidize the Ga-N bonds in the gallium nitride layer, thereby promoting the etching reaction.

[0044] Next, as shown in Figure 6(h), in step h, the surface of the p-type gallium nitride epitaxial layer 323 outside the orthographic region of the first reflective layer 311 of the platform area 400 is etched to expose the n-type gallium nitride epitaxial layer 321, forming an n-type gallium nitride epitaxial platform 321a. Furthermore, an oxide is formed on a portion of the p-type gallium nitride epitaxial layer 323 by ion implantation, forming an insulating oxide layer 324 on the p-type gallium nitride epitaxial layer 323, defining a current-limiting zone 323a on the p-type gallium nitride epitaxial layer 323, and forming a third semi-finished product 800.

[0045] Next, in step i, an insulating material layer is formed that covers the surface of the third semi-finished product 800 and exposes the p-type gallium nitride epitaxial layer 323 (current-limiting zone 323a) and the oxide layer 324. Then, a current-diffusing layer 340 made of a transparent conductive metal oxide material is deposited on the exposed surfaces of the p-type gallium nitride epitaxial layer 323 (current-limiting zone 323a) and the oxide layer 324. After that, an insulating material is deposited to cover the current-diffusing layer 340 to form an insulating layer 33, obtaining the structure shown in Figure 7(i).

[0046] Next, in step j, as shown in Figure 7(j), two etching openings are etched from the insulating layer 33 by a photolithography process, exposing the n-type gallium nitride epitaxial platform 321a and the current diffusion layer 340 to the outside of the current limiting zone 323a. Then, a metal layer is deposited to fill the two etching openings and extend to the top surface of the insulating layer 33, forming a first electrode portion 341, and a first extended electrode portion 343 and a second extended electrode portion 344, respectively, which are connected to the first electrode portion 341 and the current diffusion layer 340 and extend to the outer surface 331 of the insulating layer 33. Because there is a gap between the first extended electrode portion 343 and the second extended electrode portion 344, they are spaced apart from each other.

[0047] Next, as shown in Figure 7(k), in step k, a second reflective layer 312 is deposited in the gap, in which multiple layers of high refractive index n-type gallium nitride and multiple layers of low refractive index n-type gallium nitride are alternately stacked, and both sides of the second reflective layer 312 are connected to the first stretched electrode portion 343 and the second stretched electrode portion 344, respectively.

[0048] Finally, in step l, the sacrificial layer 81 is removed by laser etching, thereby removing the sapphire substrate 80 and exposing the first reflective layer 311. This results in the light-emitting diode 3 shown in Figure 2.

[0049] In some embodiments, etching in step g can also be performed in an alkaline environment such as a potassium hydroxide solution.

[0050] In some embodiments, etching in step g does not need to be performed under ultraviolet irradiation conditions.

[0051] In some embodiments, step l can be omitted, leaving the sapphire substrate 80 intact.

[0052] Figure 8 shows a second embodiment of the light-emitting diode package module of the present invention. The structure of this second embodiment is substantially the same as that of the first embodiment, except that in the second embodiment, the first stretched electrode portion 343 is linearly extended on the same plane as the second stretched electrode portion 344, but is not formed on the outer surface 331. The second reflective layer 312 is located in the gap between the first stretched electrode portion 343 and the second stretched electrode portion 344 and is connected only to the second stretched electrode portion 344.

[0053] Figures 9(a) and 9(b) of Figure 9 show a third and fourth embodiment of the light-emitting diode package module of the present invention, respectively. The third and fourth embodiments are similar in structure to the first and second embodiments, respectively, but differ from the first and second embodiments in that the current limiting zone 323a in the third and fourth embodiments is not defined by the oxide layer 324, but rather by the second electrode portion 342 which is in direct contact with the p-type gallium nitride epitaxial layer 323, and the connection region between the second electrode portion 342 and the p-type gallium nitride epitaxial layer 323 is defined as the current limiting zone 323a. If the current limiting zone 323a is defined by the second electrode portion 342, the current diffusion layer 340 is connected to the surface of the p-type gallium nitride epitaxial layer 323 opposite to the second electrode portion 342, and the portion of the surface of the p-type gallium nitride epitaxial layer 323 on which the second electrode portion 342 is not formed is covered by the insulating layer 33.

[0054] Thus, the manufacturing methods for the third and fourth embodiments of the light-emitting diode package module of the present invention differ from the first embodiment in that, in the third and fourth embodiments, it is not necessary to form an oxide layer 324, and therefore ion implantation is not required in step h, and thus the third semi-finished product 800 manufactured in the third and fourth embodiments does not have an oxide layer 324. Furthermore, in step i, an insulating material is deposited on the surface of the third semi-finished product 800 which does not have an oxide layer 324, and etching openings are formed using a photolithography process to expose the n-type gallium nitride epitaxial platform 321a and the p-type gallium nitride epitaxial layer 323, metal is deposited in these etching openings to form the first and second electrode portions 341 and 342, a current diffusion layer 340 made of a transparent conductive oxide material is deposited on the surface of the insulating material and the second electrode portion 342, and finally an insulating material is deposited to form an insulating layer 33. Subsequently, steps j to l are performed in the same manner as in the first embodiment, and the manufacturing of the third and fourth embodiments is completed.

[0055] As shown in Figures 10 and 11, the fifth to eighth embodiments of the light-emitting diode package module of the present invention are similar in structure to the first to fourth embodiments, respectively. The difference is that the insulating layer 33 in the fifth to eighth embodiments is formed by alternately stacking insulating material layers with different refractive indices. Therefore, after forming the insulating layer 33, the insulating layer 33 in the spacing range between the first stretched electrode portion 343 and the second stretched electrode portion 344 can be defined as the second reflective layer 312, and the insulating layer 33 and the second reflective layer 312 are integrally connected to each other. Consequently, there is no need to separately form the second reflective layer 312.

[0056] As shown in Figure 12, Figures 12(a) and 12(b) show the structure of the third embodiment of the present invention, the emission directionality of the comparative example, and the emission characteristics in a small-angle range. Here, the first reflective layer 311 is formed by stacking 25 pairs of first n-type gallium nitride layers 311a and second n-type gallium nitride layers 311b. The structure of the comparative example is the same as that of the third embodiment, except that it does not have a reflective unit 31. Furthermore, both the third embodiment and the comparative example are described as examples that emit green light. From Figure 12, it can be seen that the third embodiment has a reflective unit 31 and etching holes 311c are formed in the second n-type gallium nitride layer 311b, so compared to the case without a reflective unit 31, the emission has better straightness (parallelism), a narrower full width at half maximum, and also superior emission characteristics in a small-angle range.

[0057] In summary, the light-emitting diode package module of the present invention utilizes differences in ion doping concentration to form n-type gallium nitride layers with different reflectivity, constituting a first reflective layer 311, and combining it with a second reflective layer 312 of a different form to achieve a resonance effect. Furthermore, etching holes into the second n-type gallium nitride layer 311b with low reflectivity further enhances the effect of limiting the range from which light is emitted, improving the emission characteristics at small angles. In addition, by designing a carrier unit 2 equipped with multiple electrical connection units 22, multiple light-emitting diodes 3 can be mounted and integrated, thereby reliably achieving the objectives of the present invention.

[0058] Although embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications are possible without departing from its essence. [Explanation of Symbols]

[0059] 2 Carrier Units 21 circuit boards 211 Top surface 212 Bottom surface 213 Through hole 22 Electrical connection unit 221 First electrical connection member 222 Second electrical connection member 223 Electrical connection 223a metal pillar 223b Seed layer 224 Ball-shaped solder 3 Light-emitting diodes 31 Reflection Unit 311 First Reflecting Layer 311a First n-type gallium nitride layer 311b Second n-type gallium nitride layer 311c Etching holes 312 Second Reflecting Layer 32 Light-emitting units 321 n-type gallium nitride epitaxial layer 321a n-type gallium nitride epitaxial platform 322 Quantum well layer 323 p-type gallium nitride epitaxial layer 323a Current-limited zone 324 Oxide layer 33 Insulating layer 331 External surface 34 Electrode Units 340 Current Diffusion Layer 341 First electrode section 342 Second electrode section 343 First stretched electrode section 344 Second stretched electrode section 80 Sapphire substrate 81 layers of victims 91 Composite gallium nitride layer 400 Platform Area 500 photoresist layers 600 First semi-finished product 700 Second semi-finished product 800 Third semi-finished product T1 First etching groove T2 Second Etching Software S Silicon dioxide layer

Claims

1. A light-emitting diode package module comprising a carrier unit and a plurality of light-emitting diodes, The carrier unit comprises a substrate and a plurality of electrical connection units, the substrate having a top surface and a bottom surface facing opposite directions, and a plurality of regularly spaced through holes extending from the bottom surface to the top surface, each electrical connection unit comprising two electrical connection portions, each positioned within one of the two through holes so as to extend from the bottom surface to the top surface, a first electrical connection member positioned on the top surface side to connect to one of the two electrical connection portions, and a second electrical connection member positioned on the top surface side to connect to the other of the two electrical connection portions. The plurality of light-emitting diodes are connected to the corresponding electrical connection unit in a flip-chip format, and each light-emitting diode has a reflective unit, a light-emitting unit, an insulating layer, and an electrode unit, and the reflective unit has a first reflective layer in which n-type gallium nitride layers having different refractive indices are stacked. The light-emitting unit comprises an n-type gallium nitride epitaxial layer, a quantum well layer, and a p-type gallium nitride epitaxial layer, which are sequentially stacked from the surface of the first reflective layer, and the electrode unit comprises a first electrode portion located on the surface of the n-type gallium nitride epitaxial layer and a current diffusion layer electrically connected to the portion of the surface of the p-type gallium nitride epitaxial layer opposite to the quantum well layer. The p-type gallium nitride epitaxial layer has a current-limiting zone to which the current-diffusing layer is connected. The light-emitting diode package module is characterized in that the insulating layer covers the surfaces of the light-emitting unit, the first electrode portion, and the current diffusion layer, the electrode unit further has a first stretched electrode portion and a second stretched electrode portion that penetrate the insulating layer and are electrically connected to the first electrode portion and the current diffusion layer, respectively, the second stretched electrode portion is located outside the orthographic projection range of the current limiting zone, a gap exists between the first stretched electrode portion and the second stretched electrode portion, the orthographic projection range of the gap covers at least the entire current limiting zone, each light-emitting diode is connected to the corresponding electrical connection unit via the first stretched electrode portion and the second stretched electrode portion, the reflective unit further has a second reflective layer located between the first stretched electrode portion and the second stretched electrode portion, the reflectivity of the second reflective layer is greater than that of the first reflective layer, and the current limiting zone is located within the orthographic projection range of the second reflective layer.

2. The light-emitting diode package module according to claim 1, wherein the first reflective layer is formed by alternately stacking a plurality of first n-type gallium nitride layers with a high refractive index and a plurality of second n-type gallium nitride layers with a low refractive index, and pyramidal etching holes are formed in the second n-type gallium nitride layers.

3. The light-emitting unit further comprises an oxide layer formed on the p-type gallium nitride epitaxial layer, the oxide layer defining the current-limiting zone on the p-type gallium nitride epitaxial layer, and the current-diffusing layer formed on the surfaces of the p-type gallium nitride epitaxial layer and the oxide layer, as described in claim 1.

4. The light-emitting diode package module according to claim 1, wherein the electrode unit further comprises a second electrode portion interposed between the p-type gallium nitride epitaxial layer and the current diffusion layer, and directly connected to the p-type gallium nitride epitaxial layer and the current diffusion layer, the connection region between the second electrode portion and the p-type gallium nitride epitaxial layer defines the current limiting zone, and the insulating layer also covers the surface of the second electrode portion.

5. The light-emitting diode package module according to claim 1, wherein the width of the current limiting zone is within the range of 5 μm to 30 μm.

6. The current diffusion layer has a transmittance greater than 80%, as described in claim 1 of the light-emitting diode package module.

7. The light-emitting diode package module according to claim 1, wherein the insulating layer has an outer surface located above the p-type gallium nitride epitaxial layer, the second stretched electrode portion extends to the outer surface of the insulating layer, and the surfaces of the first stretched electrode portion and the second stretched electrode portion connected to the electrical connection unit are located on the same plane.

8. The light-emitting diode package module according to claim 1, wherein the second reflective layer is located in the gap between the first stretched electrode portion and the second stretched electrode portion and is connected to at least the second stretched electrode portion.

9. The light-emitting diode package module according to claim 8, wherein both the first stretched electrode portion and the second stretched electrode portion are extended to the top surface of the insulating layer, and both ends of the second reflective layer are connected to the first stretched electrode portion and the second stretched electrode portion, respectively.

10. The light-emitting diode package module according to claim 1, wherein the ratio of the orthographic area of ​​the second reflective layer to the orthographic area of ​​the current limiting zone is in the range of 1.5 to 2.

11. The light-emitting diode package module according to claim 1, wherein the second reflective layer is either a Bragg reflective structure or a non-conductive cladding structure, and the non-conductive cladding structure comprises a translucent insulator and a metal cladding layer covered by the insulator and composed of aluminum or silver.

12. The light-emitting diode package module according to claim 1, wherein the insulating layer and the second reflective layer are formed by alternately stacking insulating material layers with different refractive indices, and the insulating layer and the second reflective layer are integrally connected to each other.

13. The light-emitting unit further comprises a sloping side surface whose width gradually increases from the surface of the p-type gallium nitride epitaxial layer toward the quantum well layer, and the angle between the sloping side surface and the surface of the p-type gallium nitride epitaxial layer is 150 degrees or more, as described in claim 1.

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