TWI479696B - Led device - Google Patents

Description

Light-emitting diode device

The present invention relates to a light-emitting diode device, and more particularly to a light-emitting diode device having a double-sided reflective layer in a laminated structure of crystal grains.

For the light-emitting diode device, how to improve the luminous efficiency has been an important issue. In the prior art, many different solutions have been proposed, one of which is to form the surface of the base of the light-emitting diode die into a reflective surface having a concave-convex structure so as to make the inside of the light-emitting diode die Light is reflected to the outside.

FIG. 1A is a schematic view showing a conventional LED device before being packaged; FIG. 1B is a schematic view showing the LED device of FIG. 1A after being packaged. Referring to FIGS. 1A and 1B , the LED device 110 includes a light emitting diode die 112 and a package body 124 . The package body 124 carries and encapsulates the die 112 , and the inner side surface 126 is a reflective surface. The LED die 112 includes a sapphire substrate 114 and a stacked structure 116. The stacked structure 116 is disposed on the sapphire substrate 114 and includes a buffer layer 150, an n-type contact layer 152 formed of gallium nitride, The n-type electrode 154, the light-emitting layer 156, the p-type contact layer 158 composed of gallium nitride, the gallium nitride-doped magnesium layer 160, the indium tin oxide layer 162, and the p-type electrode 164. The layers of the light-emitting diode die 112, the material of the package body 124, and the method for forming the package are all known in the art. For details, refer to the contents of the Chinese Patent Publication Nos. 575970, 567618, 523939, and 522579, and no further details are provided herein. Referring again to FIG. 1B, the surface of the sapphire substrate 114 has a concave-convex reflective structure 114a that reflects the light RL from the light-emitting layer 156 to the package 124 and is reflected by the inner side surface 126 to the outside of the light-emitting diode device 110.

However, the luminous efficiency of the light-emitting diode device having the above structure still needs to be improved.

In view of the above problems, the present invention provides a laminated structure of crystal grains having a light-emitting diode device having a double-sided reflective layer.

In an embodiment, the light emitting diode device includes a die. The die includes a substrate and a laminate structure. The laminate structure is located on the substrate and includes an intermediate portion and a peripheral portion that are independent of each other. The peripheral portion is located around the intermediate portion and has an inner side facing the intermediate portion. The inner side has a reflective layer, and the reflective layer has a first reflective surface and a second reflective surface. The first reflecting surface faces the intermediate portion, and the second reflecting surface is in contact with the inner side surface of the surrounding portion.

In another embodiment, a light emitting diode device includes: a die including a substrate and a laminate structure on the substrate and including an intermediate portion and a periphery independent of each other a portion, the peripheral portion is located around the intermediate portion and has an inner side surface having a reflective layer, and the reflective layer has a first reflective surface and a second reflective surface, the first reflective surface Facing the intermediate portion, and the second reflective surface is in contact with the inner side surface of the surrounding portion; and a package carrying and surrounding the die, the inner side surface and the inner bottom surface of the package body are respectively a third reflective surface and a fourth reflective surface, wherein the third reflective surface faces and is substantially parallel to the second reflective surface; wherein the substrate is made of a light transmissive material, and the substrate and the intermediate portion contact region The surface is permeable to light, and the substrate has a thickness sufficient for a portion of the light of the light-emitting layer of the intermediate portion to pass through the surface of the contact region and then reflect at the fourth reflective surface and reach the third reflective surface.

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

2A-2D are schematic views showing the process of a light-emitting diode device according to an embodiment of the present invention.

In particular, in the embodiment of FIGS. 2A to 2D, the die 212 itself has a reflective layer 222 having a reflective function on both sides, and the reflective layer 222 is located around the structure of the die 212 itself (ie, is formed). The so-called "reflector" causes the light emitted by the light-emitting layer 232 of the die 212 (especially the side light of the die 212) to be effectively reflected to the outside of the light-emitting diode device 210 by such a reflective layer 222. The utilization efficiency of the light on the side of the crystal chip 212 is improved, and the luminous efficiency of the entire light-emitting diode device 210 is further improved. On the other hand, such a reflective layer 222 can also prevent the light emitted by the light-emitting layer 232 of the die 212 from entering the semiconductor structure of the die 212 itself to generate thermal energy, which helps to improve the photoelectric efficiency of the LED device 210. The term "sidelight" refers to the light emitted from the side of the die 212, and is redirected by the reflective layer 222 to become so-called "forward light" to the outside of the LED device 210. Here, the term "forward light" generally refers to the light emitted by the light-emitting diode device 210.

FIG. 2A illustrates a die 212 semi-finished product that has not been packaged by the light emitting diode device. The die 212 semi-finished product includes a substrate 214 and a laminate structure 216. The laminate structure 216 is disposed on the substrate 214 and includes an intermediate portion 218 and a peripheral portion 220 that are independent of each other. The peripheral portion 220 is located around the intermediate portion 218 and There is an inner side 220a. In the preferred embodiment, the peripheral portion 220 surrounds the intermediate portion 218. The laminated structure 216 includes a buffer layer 250, an n-type contact layer 252 composed of gallium nitride, an n-type electrode 254, a light-emitting layer 232, a p-type contact layer 258 composed of gallium nitride, a gallium nitride-doped magnesium layer 260, and an indium. Tin oxide layer 262, p-type electrode 264. The substrate 214 may be made of a conductive or non-conductive material; the laminated structure 216 is formed by sequentially forming a buffer layer 250 on the substrate 214, an n-type contact layer 252 composed of gallium nitride, a light-emitting layer 232, and nitriding. The p-type contact layer 258, the gallium nitride-doped magnesium layer 260, and the indium tin oxide layer 262 are formed by gallium. For the materials and formation methods of the above layers, reference may be made to the patent documents contained in the prior art, and no further description is provided herein. . In this embodiment, after the formation of the gallium nitride doped magnesium layer 260, between the intermediate portion 218 and the surrounding portion 220 is defined by the inductively coupled plasma in the peripheral region of the laminate formed by the above layers. The opening (as shown in Fig. 2A) is adjustable in various sizes and shapes depending on the design and needs. Next, the conventional electrode process is continued to form an n-type electrode 254 and a p-type electrode 264 on the n-type contact layer 252 and the p-type contact layer 258, respectively. At this point, the die 212 semi-finished product shown in FIG. 2A can be obtained.

FIG. 2B is a schematic view showing the semi-finished product of the die 212 shown in FIG. 2A forming a reflective layer having a reflective function on both sides. Note that, for convenience of explanation, the reflective layer 222 of the right portion of FIG. 2B is appropriately translated from the inner side 220a of the surrounding portion 220 to the upper left. The reflective layer 222 may be a single layer or a laminated structure, and the material thereof may be a metal, an oxide, or a laminated combination of an oxide and a metal, and the method of forming may suitably utilize various conventional techniques. If the reflective layer 222 is a metal, materials which may be used include silver or aluminum. If the reflective layer 222 is an oxide, a laminated structure such as SiO ₂ , TiO ₂ or SiO ₂ and TiO ₂ may be employed. The reflective layer 222 may have a silver/SiO ₂ laminated structure, a silver/TiO ₂ laminated structure, an aluminum/SiO ₂ laminated structure, an aluminum/TiO ₂ laminated structure, or the above metal, if it is a laminated structure of an oxide and a metal. Other combinations with oxides. In this embodiment, the reflective layer 222 is formed on the inner side surface 220a of the peripheral portion 220 and extends to the upper surface of the peripheral portion 220, and has a first reflective surface 222a and a second reflective surface 222b, wherein the first reflection The face 222a faces the intermediate portion 218, and the second reflecting surface 222b is in contact with the inner side surface 220a of the peripheral portion 220. It is to be noted that in this embodiment, the portion of the surface 234 of the substrate 214 between the intermediate portion 218 and the peripheral portion 220 is not covered by the reflective layer 222 to be exposed. In another embodiment, the reflective layer 222 is a stacked structure of oxide and metal, wherein the first reflective surface 222a is composed of an oxide and the second reflective surface 222b is composed of a metal.

2C is a schematic view showing the package of the die 212 shown in FIG. 2B. As shown in FIG. 2C, after the die 212 is completed, it is packaged by a package 224. The package 224 carries and surrounds the die 212. The package 224 has an inner side 226 and an inner bottom surface 228. It is to be noted that, for the sake of brevity, the symbols indicating each element of the die 212 are not repeated in FIG. 2C and FIG. 2D described later, and FIG. 2A and FIG. 2B are referred to if necessary.

2D is a schematic view showing a completed LED device of the package. It is to be noted that in this embodiment, the LED device 210 includes the die 212 and the package 224. As described above, the reflective layer 222 of the die 212 has a first reflective surface 222a and a second reflective surface 222b, wherein the first reflective surface 222a faces the intermediate portion 218, and the second reflective surface 222b is surrounded by The inner side 220a of the portion 220 is in contact. In addition, the inner side surface 226 and the inner bottom surface 228 of the package body 224 are respectively a third reflecting surface (ie, 226) and a fourth reflecting surface (ie, 228), wherein the third reflecting surface 226 faces and substantially Parallel to the second reflecting surface 222b. Moreover, in this embodiment, the substrate 214 is constructed of a light transmissive material. The substrate 214 has a contact area I for contact with the intermediate portion 218. The surface of the contact area I is transparent. The thickness of the substrate 214 is sufficient for the partial light RL ₁ of the light-emitting layer 232 of the intermediate portion 218 to pass through the surface of the contact region I and then reflected to the outside at the fourth reflective surface 228. In another embodiment, the thickness of the substrate 214 is sufficient for the partial light RL ₁ of the light-emitting layer 232 of the intermediate portion 218 to pass through the surface of the contact region I, and then reflected at the fourth reflective surface 228 and reaches the third reflective surface 226. It is reflected to the outside world. In still another embodiment, the thickness of the substrate 214 is sufficient for the partial light RL ₁ of the light-emitting layer 232 of the intermediate portion 218 to pass through the surface of the contact region I, and then reflected at the fourth reflective surface 228 and reaches the third reflective surface 226 and The second reflecting surface 222b is further reflected to the outside. In this embodiment of the invention, the thickness of the substrate 214 can be between 5 μm and 100 μm.

In one embodiment, the horizontal distance d ₃ of the second reflecting surface 222b and the third reflecting surface 226 is not more than half of the horizontal distance of the bottom edge of the inner edge of the package 224 (ie, the inner diameter of the package 224) d ₁ , that is, d ₃ ≦(1/2)d ₁ . As long as the relationship of d ₃ ≦(1/2)d ₁ is satisfied, it is sufficient for the partial ray RL _{1 of the} luminescent layer 232 to be reflected by the third reflecting surface 226 to reach the second reflecting surface 222b.

In one embodiment, the peripheral portion 220 and the intermediate portion 218 have substantially the same height, between 5 μm and 15 μm. In another embodiment, the height of the surrounding portion 220 and the intermediate portion 218 are substantially the same, but not limited thereto. In another embodiment, the peripheral portion 220 is slightly above the intermediate portion 218. In yet another embodiment, the peripheral portion 220 is slightly lower than the intermediate portion 218.

In one embodiment, the substrate 214 is exposed between the upper surface 234 between the intermediate portion 218 and the peripheral portion 220, and the distance d ₂ from the bottom of the intermediate portion 218 to the bottom of the reflective layer 222 is no more than 1 μm.

In one embodiment, the inner side 220a of the peripheral portion 220 (or the second reflective surface 222b of the reflective layer 222) has an acute angle θ with the upper surface of one of the substrates 214, and the acute angle θ is less than 90 degrees. In another embodiment, the acute angle θ is between 30 and 80 degrees. In a preferred embodiment, the acute angle θ is between 40 and 60 degrees.

In summary, the LED device disclosed in the embodiments of the present invention can further improve the overall luminous efficiency and can also improve the photoelectric efficiency. In addition, the substrate 214 disclosed in the embodiments of the present invention may also adopt a conductive substrate.

Although the present case is illustrated by a number of preferred embodiments, those skilled in the art can make various forms of changes without departing from the spirit and scope of the present invention. The above implementations are for illustrative purposes only and are not intended to limit the scope of the present invention. All kinds of modifications or changes that are not in violation of the spirit of the case are the scope of patent application in this case.

110. . . Light-emitting diode device

112. . . Grain

114. . . Base

114a. . . Concave structure

116. . . Laminated structure

124. . . Package

126. . . Inner side

150. . . The buffer layer

152. . . N-type contact layer

154. . . N-type electrode

156. . . Luminous layer

158. . . P-type contact layer

160. . . Magnesium nitride layer

162. . . Indium tin oxide layer

164. . . P-electrode

210. . . Light-emitting diode device

212. . . Grain

214. . . Base

216. . . Laminated structure

218. . . Middle part

220. . . Surrounding part

220a. . . Inner side

222. . . Reflective layer

222a. . . First reflecting surface

222b. . . Second reflecting surface

224. . . Package

226. . . Third reflecting surface

228. . . Fourth reflecting surface

232. . . Luminous layer

234. . . surface

250. . . The buffer layer

252. . . N-type contact layer

254. . . N-type electrode

258. . . P-type contact layer

260. . . Gallium nitride doped magnesium layer

262. . . Indium tin oxide layer

264. . . P-electrode

d ₁ , d ₂ , d ₃ . . . distance

I. . . Contact area

θ. . . Angle

RL, RL ₁ . . . Light

FIG. 1A is a schematic view showing a conventional light emitting diode device before being packaged.

FIG. 1B is a schematic diagram of the LED device of FIG. 1A after being packaged.

2A-2D are schematic views showing the process of a light-emitting diode device according to an embodiment of the present invention.

210‧‧‧Lighting diode device

212‧‧‧ grain

214‧‧‧Base

216‧‧‧Laminated structure

218‧‧‧ middle part

220‧‧‧ surrounding parts

220a‧‧‧ inside

222‧‧‧reflective layer

222a‧‧‧first reflective surface

222b‧‧‧second reflective surface

224‧‧‧Package

226‧‧‧ third reflecting surface

228‧‧‧fourth reflecting surface

232‧‧‧Lighting layer

234‧‧‧ surface

250‧‧‧buffer layer

252‧‧‧n type contact layer

254‧‧‧n type electrode

258‧‧‧p type contact layer

260‧‧‧ gallium nitride doped magnesium layer

262‧‧‧Indium tin oxide layer

264‧‧‧p-type electrode

D1, d2, d3‧‧‧ distance

I. . . Contact area

θ. . . Angle

RL1. . . Light

Claims (20)

A light emitting diode device comprising: a die comprising a substrate and a semiconductor laminate structure on the substrate, wherein the semiconductor laminate structure comprises an intermediate portion and a peripheral portion independent of each other, the peripheral portion Between the intermediate portion and having an inner side surface of the intermediate portion; and a reflective layer having a first reflective surface and a second reflective surface, wherein the first reflective surface faces the intermediate portion And the second reflecting surface is in contact with the inner side surface of the surrounding portion. The illuminating diode device of claim 1, further comprising: a package carrying and surrounding the die, wherein an inner side surface and an inner bottom surface of the package body are respectively a third reflecting surface and a first a fourth reflecting surface; wherein the intermediate portion comprises a light emitting layer, the substrate is made of a light transmissive material and has an intermediate contact region for contacting the intermediate portion, and the surface of the intermediate contact region is transparent, and the substrate is The thickness is sufficient for the light of the luminescent layer to pass through the surface of the intermediate contact region and then reflected at the fourth reflective surface. The light-emitting diode device of claim 1, wherein the substrate has a thickness of between 5 μm and 100 μm. The illuminating diode device of claim 2, wherein a horizontal distance between the second reflecting surface and the third reflecting surface is not more than half of an inner diameter of the package, sufficient for the light of the luminescent layer to be in the third After the reflecting surface reflects, the second reflecting surface is reached. The light-emitting diode device of claim 1, wherein the peripheral portion has substantially the same height as the intermediate portion. The light-emitting diode device of claim 1, wherein the reflective layer is composed of a metal or an oxide. The light-emitting diode device of claim 6, wherein the reflective layer is an oxide or a stacked structure of a metal and an oxide. The light-emitting diode device of claim 6, wherein the material of the reflective layer is selected from the group consisting of silver, aluminum, SiO ₂ and TiO ₂ . The light-emitting diode device of claim 1, wherein the substrate is exposed on an upper surface between the intermediate portion and the peripheral portion, and a distance from a bottom portion of the intermediate portion to a bottom portion of the reflective layer is not greater than 1 μm. The illuminating diode device of claim 1, wherein the inner side of the peripheral portion has an acute angle with an upper surface of the substrate, and the acute angle is between 40 degrees and 60 degrees. A light emitting diode device comprising: a die comprising a substrate and a semiconductor laminate structure on the substrate; wherein the semiconductor laminate structure comprises an intermediate portion and a peripheral portion independent of each other, the peripheral portion Is located around the middle part And having an inner side surface; a reflective layer, the reflective layer is made of metal or oxide, and the reflective layer has a first reflective surface and a second reflective surface, wherein the first reflective surface faces the intermediate portion And the second reflective surface is in contact with the inner side surface of the surrounding portion; and a package that carries and surrounds the die, and an inner side surface and an inner bottom surface of the package body are respectively a third reflective surface and a fourth reflecting surface, wherein the third reflecting surface faces the second reflecting surface; wherein the intermediate portion comprises a light emitting layer, the substrate is composed of a light transmissive material and has an intermediate contact region and the intermediate portion Contacting, and the surface of the intermediate contact region is transparent, and the thickness of the substrate is sufficient for the light of the light-emitting layer of the intermediate portion to pass through the surface of the intermediate contact region to be reflected on the fourth reflective surface, and reach the first Three reflective surfaces. The light-emitting diode device of claim 11, wherein the substrate has a thickness of between 5 μm and 100 μm. The illuminating diode device of claim 11, wherein a horizontal distance between the second reflecting surface and the third reflecting surface is not more than half of an inner diameter of the package, sufficient for the light of the luminescent layer to be in the third After the reflecting surface reflects, the second reflecting surface is reached. The light-emitting diode device of claim 11, wherein the reflective layer is a stacked structure of an oxide and a metal, and the first reflective surface is composed of the oxide, and the second reflective surface is composed of the metal . The light-emitting diode device of claim 14, wherein the material of the reflective layer is selected from the group consisting of silver, aluminum, SiO ₂ and TiO ₂ . The light-emitting diode device of claim 14, wherein the reflective layer is a laminated structure of SiO ₂ and TiO ₂ . The illuminating diode device of claim 11, wherein the substrate is exposed on an upper surface between the intermediate portion and the peripheral portion, and a distance from a bottom portion of the intermediate portion to a bottom portion of the reflective layer is not greater than 1 μm. The light-emitting diode device of claim 11, wherein the inner side of the peripheral portion has an acute angle with an upper surface of the substrate, and the acute angle is between 40 degrees and 60 degrees. The illuminating diode device of claim 11, wherein the third reflecting surface of the package is substantially parallel to the second reflecting surface. The illuminating diode device of claim 11, wherein the peripheral portion has substantially the same height as the intermediate portion.