TWI581467B - Flip-chip light-emitting diode package and fabricating method thereof - Google Patents

Description

Flip-chip type light emitting diode package and manufacturing method thereof

The present invention relates to a flip chip type light emitting diode package.

Light-emitting diodes are one of the most prosperous industries in recent years. Light-emitting diodes have the advantages of energy saving, fast response, long life cycle and environmental protection. The emerging flip-chip LEDs have high light efficiency. , good heat dissipation, free of wire and other advantages. Generally, a single-crystal light-emitting diode has a narrow light-emitting band, and a fluorescent material is often used in the process. The fluorescent material can convert the wavelength of the light emitted by the light-emitting diode to another wavelength, thus The light emitted by the fluorescent material is mixed with the light emitted by the light emitting diode chip to generate white light. In addition, the design of the reflector cup improves the light efficiency and optimizes the beam distribution, which results in a highly efficient white light source. However, the white light generated by this method will cause serious color separation after passing through the secondary optical element. One of the reasons is that the design of the reflective cup causes the light emitted by the fluorescent material and the light emitted by the LED chip to be emitted. Completely overlapping.

The invention provides a flip-chip type light emitting diode package for solving the above problem of color separation.

One aspect of the present invention provides a flip-chip light emitting diode package comprising a light source body and a reflective layer. The light source body includes a light emitting diode chip and a wavelength conversion layer. The LED substrate has a top surface of the wafer, a bottom surface of the wafer, and a wafer side surface adjacent to the top surface of the wafer and the bottom surface of the wafer and surrounding the surface of the wafer. The LED substrate has two electrodes disposed on the bottom surface of the wafer. The wavelength conversion layer is correspondingly disposed on the top surface of the wafer, and has a light-emitting surface and a wavelength conversion layer side surface surrounding the wavelength conversion layer, wherein the wafer side surface and the wavelength conversion layer side surface are defined as a light source body side surface. The reflective layer surrounds and covers the side surface of the light source body, and exposes the light surface and the two electrodes.

In one or more embodiments of the invention, the reflective layer comprises cerium oxide and a silicone or resin.

In one or more embodiments of the invention, the wavelength converting layer is an encapsulant comprising a wavelength converting substance.

In one or more embodiments of the invention, the wavelength converting material is one or a combination of phosphors, pigments or pigments.

In one or more embodiments of the invention, the upper surface of the reflective layer is flush with the exit surface of the wavelength conversion layer.

Another aspect of the present invention provides a method of fabricating a flip-chip light emitting diode package, comprising providing a light emitting diode wafer having a first surface and a second surface on a different side to form an epitaxial structure Forming a plurality of electrodes on the surface of the epitaxial structure layer on the first surface to form a wavelength conversion material Layered on the second surface, the epitaxial light-emitting diode wafer is split to form a plurality of light source bodies, providing an adhesive layer, and the bottom surface of each light source body is fixed on the adhesive layer to form a reflective material layer covering Surrounding the light source body, polishing the reflective material layer to expose the light-emitting surface on each light source body, and cutting the reflective material layer to form a plurality of light-emitting diode packages spaced apart from each other, and each of the light-emitting diode packages includes a light source body And a layer of reflective material coated on the side surface of the light source body, and finally the adhesive layer is removed to form a plurality of light emitting diode packages. Each light source body includes a light emitting diode wafer composed of an epitaxial structure layer, a wavelength conversion layer composed of a wavelength conversion material layer, and a pair of electrodes. The light emitting diode chip has a top surface of the wafer, a bottom surface of the wafer, and a wafer side surface adjacent to the top surface of the wafer and the bottom surface of the wafer and surrounding the LED body. The wavelength conversion layer is formed on the top surface of the wafer, and the wavelength conversion layer has a light exit surface and a wavelength conversion layer side surface surrounding the wavelength conversion layer. The electrode is formed on the bottom surface of the wafer. The wafer side surface and the wavelength conversion layer side surface are defined as a light source body side surface.

In one or more embodiments of the invention, the layer of reflective material comprises cerium oxide and a silicone or resin.

In one or more embodiments of the invention, the wavelength converting layer is an encapsulant comprising a wavelength converting substance.

In one or more embodiments of the invention, the wavelength converting material is one or a combination of phosphors, pigments or pigments.

The invention surrounds the wavelength conversion layer by the reflection layer, so that the wavelength conversion layer and the light-emitting diode wafer have substantially the same light-emitting area, and thus, the flip-chip light-emitting diode of the invention can emit a uniform mixed wide wave. Duan Guang, reducing the occurrence of color separation.

100‧‧‧Flip-chip LED package

200‧‧‧Light source body

202‧‧‧Light source side surface

210‧‧‧Light Emitter Wafer

212‧‧‧Top surface of the wafer

214‧‧‧ wafer bottom

216‧‧‧ wafer side surface

218‧‧‧ electrodes

220‧‧‧wavelength conversion layer

222‧‧‧Glossy

224‧‧‧wavelength conversion layer side surface

300‧‧‧reflective layer

400‧‧‧Light Emitting Diode Wafer

410‧‧‧ first surface

420‧‧‧ second surface

500‧‧‧ epitaxial structure layer

600‧‧‧wavelength conversion material layer

700‧‧‧Adhesive layer

800‧‧‧reflective material layer

1 is a perspective view of a flip-chip type LED package in an embodiment of the present invention.

2 is a cross-sectional view of the flip-chip type LED package of FIG. 1 taken along line A-A.

3A to 3F are schematic views showing different stages of a method of manufacturing a flip-chip type LED package in an embodiment of the present invention.

4 is a cross-sectional view showing a flip-chip type LED package in another embodiment of the present invention.

The various embodiments of the present invention are disclosed in the drawings, and in the claims However, it should be understood that these practical details are not intended to limit the invention. That is, in some embodiments of the invention, these practical details are not necessary. In addition, some of the conventional structures and elements are shown in the drawings in a simplified schematic manner in order to simplify the drawings.

Referring to Fig. 1, there is shown a perspective view of one embodiment of a flip chip type LED package 100 of the present invention. The appearance of the flip-chip LED package 100 includes a light-emitting surface 222 and a reflective layer 300. The light-emitting surface 222 is a surface on which the light of the flip-chip light-emitting diode package 100 is emitted outward. anti- The shot layer 300 surrounds the light exit surface 222.

Referring to FIG. 2, FIG. 2 is a cross-sectional view of the flip-chip type LED package 100 of FIG. 1 taken along line A-A. The flip chip type LED package 100 includes a light source body 200 and a reflective layer 300. The light source body 200 includes a light emitting diode wafer 210 and a wavelength conversion layer 220. The LED substrate 210 has a wafer top surface 212, a wafer bottom surface 214, and a wafer top surface 212 and a wafer bottom surface 214 and surrounds the wafer side surface 216 of the LED wafer 210. The LED wafer 210 has two electrodes 218. It is provided on the bottom surface 214 of the wafer. The wavelength conversion layer 220 is correspondingly disposed on the top surface 212 of the wafer, and has a light exit surface 222 and a wavelength conversion layer side surface 224 surrounding the wavelength conversion layer 220. The wafer side surface 216 and the wavelength conversion layer side surface 224 are defined as the light source body side surface 202. . The reflective layer 300 surrounds the light source body 200 and covers the light source body side surface 202, and exposes the light surface 222 and the two electrodes 218.

The reflective layer 300 surrounds the light source body 200 to maintain the forward light emission of the light emitted by the flip-chip LED package 100. The reflective layer 300 is a material having high reflectivity and reflecting light, for example, containing cerium oxide and tantalum or Resin.

In one or more embodiments of the present invention, the wavelength conversion layer 220 is an encapsulant containing a wavelength converting substance, wherein the wavelength converting substance may be one of or a combination of a phosphor powder, a pigment or a pigment, and the function thereof is to emit light. The light generated by the diode wafer 210 is wavelength-converted by a fluorescence ratio at a certain ratio, wherein the conversion ratio of the fluorescence effect is related to the material selection, thickness, and the like of the wavelength conversion layer 220.

When the light emitting diode chip 210 generates light in a divergent manner, the portion The portion of the light is emitted to the reflective layer 300 surrounding the light emitting diode wafer 210 and is reflected by the reflective layer 300 to prevent light from escaping from the wafer side surface 216 of the light emitting diode wafer 210. The path of the light also changes the direction of advance after one or more reflections, and diverges from the top surface 212 of the wafer or the bottom surface 214 of the wafer of the LED wafer 210. In other embodiments, the wafer bottom surface 214 of the LED wafer 210 can also be associated with a reflective design to increase the intensity of light emerging from the top surface 212 of the wafer.

Similarly, when the light generated by the LED chip 210 is emitted by the top surface 212 of the wafer and advanced in the wavelength conversion layer 220, a portion of the light is wavelength-converted, that is, generated by the LED chip 210. A portion of the light is absorbed by the wavelength converting material of the wavelength converting layer 220 and excited to have another light that is different from the original wavelength. The light (a portion of the original light that has undergone wavelength conversion) and a portion of the original light that is not wavelength-converted are transmitted to the reflective layer 300 surrounding the wavelength conversion layer 220. The reflective layer 300 reflects the light to avoid light from The wavelength conversion layer side surface 224 of the wavelength conversion layer 220 diverges, and the path of the light also changes the direction of advance after one or more reflections, and diverges from the light exit surface 222 of the wavelength conversion layer 220. In one or more embodiments of the present invention, the upper surface 302 of the reflective layer 300 is flush with the light exit surface 222 of the wavelength conversion layer 220.

Therefore, when the light source body 200 performs the light emitting action, the light emitting diode chip 210 generates light, and the wavelength conversion layer 220 wavelength-converts part of the light, and the light generated by the light source body 200 passes through the wavelength conversion layer 220 from the light emitting surface 222. Shoot out. Wavelength converted light and unpassed wave The light after the long conversion is mixed, so that the light source body 200 can generate a relatively broad spectrum of light emission. Limited by the reflective layer 300, the wavelength-converted light and the un-wavelength-converted light can only be emitted outward from the exposed light-emitting surface 222.

The light-emitting area refers to the area of the generated light. For example, the top surface 212 of the light-emitting diode wafer 210 can be regarded as the light-emitting area, and the light-emitting surface 222 of the wavelength conversion layer 220 can be regarded as the light-emitting area. The light-emitting area is the area of the light-emitting diode package 210 and the wavelength conversion layer 220. The light-emitting surface 222 is limited by the reflective layer 300. Its light output area.

In one or more embodiments of the present invention, since the wavelength conversion layer 220 is disposed correspondingly on the LED substrate 210, the wafer top surface 212 of the LED substrate 210 and the light exit surface 222 of the wavelength conversion layer 220 are provided. The sizes are similar, so the illuminating areas of the two are similar, and the wavelength-converted light has a similar illuminating area as the un-wavelength-converted light. The arrangement of the reflective layer 300 allows the light-emitting diode wafer 210 and the wavelength conversion layer 220 to have the same light-emitting area. In this way, the light-emitting area is similar to the light-emitting area, that is, the light-emitting area of the wavelength conversion layer 220 (the area of the light-emitting surface 222) is equal to the light-emitting area of the wavelength conversion layer 220 (the area of the light-emitting surface 222), and the light-emitting diode wafer 210 is The light-emitting area (the area of the light-emitting surface 222) is similar to the light-emitting area of the light-emitting diode wafer 210 (the area of the top surface 212 of the wafer), and both have the same light-emitting area, so that the flip-chip light-emitting diode package 100 is like A source of uniform divergence.

Another embodiment of the present invention is a flip chip type light emitting diode The manufacturing method refers to FIGS. 3A to 3F, which are schematic views of different stages of the manufacturing method of the flip-chip type LED package in one embodiment of the present invention. Referring to FIG. 3A, a method of fabricating a flip-chip LED package 100 includes providing a light-emitting diode wafer 400 having a first surface 410 and a second surface 420 on a different side. . An epitaxial structure layer 500 is formed on the first surface 410, and a plurality of electrodes 218 are formed on the surface of the epitaxial structure layer 500. The epitaxial structure layer 500 includes a p-type semiconductor and an n-type semiconductor structure.

Referring to FIG. 3B, thereafter, a wavelength converting material layer 600 is formed on the second surface 420. The material of the wavelength conversion material layer 600 is an encapsulant containing a wavelength converting substance, wherein the wavelength converting substance may be one of a phosphor powder, a pigment or a pigment or a combination thereof. The encapsulant containing the wavelength converting substance may be coated on the second surface 420, or the mold and the platen may be molded and injected with the encapsulant containing the wavelength converting substance on the second surface 420, and then baked to contain the wavelength converting substance. The encapsulant is cured to cure the encapsulant containing the wavelength converting material to form the wavelength converting material layer 600.

Next, as shown in FIG. 3C, the epitaxial light-emitting diode wafer 400 is cut and split by a cutting tool to form a plurality of light source bodies 200, each of which includes an epitaxial structure layer 500 and a portion. A light-emitting diode wafer 210 composed of a plurality of light-emitting diode wafers 400, a wavelength conversion layer 220 composed of a wavelength conversion material layer 600, and a pair of electrodes 218. The LED substrate 210 has a wafer top surface 212, a wafer bottom surface 214, and a wafer side surface 216 that surrounds the wafer top surface 212 and the wafer bottom surface 214 and surrounds the LED wafer 210. The wavelength conversion layer 220 is formed on the top surface 212 of the wafer The wavelength conversion layer 220 has a light exit surface 222 and a wavelength conversion layer side surface 224 surrounding the wavelength conversion layer 220. An electrode 218 is formed on the bottom surface 214 of the wafer. The wafer side surface 216 and the wavelength conversion layer side surface 224 are defined as a light source body side surface 202.

FIG. 3C further includes providing an adhesive layer 700 for fixing the wafer bottom surface 214 of each light source body 200 to the adhesive layer 700 for facilitating handling and positioning of the light source body 200.

As shown in FIG. 3D, a mold is used to mold the mold, a reflective material is injected around the light source body 200, and the reflective material is cured to form a reflective material layer 800 for covering and surrounding the light source body 200, and The upper surface of the reflective material layer 800 is higher than the light exit surface 222. The reflective material layer 800 comprises cerium oxide and a silicone or resin.

Next, as shown in FIG. 3E, the reflective material layer 800 is polished using an abrasive tool to expose the light-emitting surface 222 on each of the light source bodies 200 such that the height of the light-emitting surface 222 is flush with the height of the reflective material layer 800.

Thereafter, as shown in FIG. 3F, the reflective material layer 800 is subjected to a dicing process to form a plurality of flip-chip light-emitting diode packages 100 spaced apart from each other, and each flip-chip LED package 100 includes a light source. The body 200 and the reflective material layer 800 coated on the side surface 202 of the light source body. The adhesive layer 700 is removed to form a plurality of flip-chip LED packages 100.

Referring to FIG. 4, FIG. 4 is a cross-sectional view showing another embodiment of the flip-chip type LED package of the present invention, wherein a flip-chip LED package 100 includes a light source body 200 and a reflection. Layer 300. The light source body 200 includes a light emitting diode wafer 210 and a wavelength conversion layer 220. Luminous dipole The body wafer 210 has a wafer top surface 212, a wafer bottom surface 214, and a wafer top surface 212 and a wafer bottom surface 214 and surrounds the wafer side surface 216 of the LED wafer 210. The LED wafer 210 has two electrodes 218 disposed on the wafer. Bottom surface 214. The wavelength conversion layer 220 is correspondingly disposed on the top surface 212 of the wafer, and has a light exit surface 222 and a wavelength conversion layer side surface 224 surrounding the wavelength conversion layer 220. The wafer side surface 216 and the wavelength conversion layer side surface 224 are defined as the light source body side surface 202. . The reflective layer 300 surrounds and covers the light source body side surface 202, and exposes the light surface 222 and the two electrodes 218. In this embodiment, the area of the light-emitting surface 222 of the wavelength conversion layer 220 is slightly larger than the area of the top surface 212 of the wafer of the LED substrate 210. For example, in the figure, the wafer-side surface 216 is disposed on a slope, and the LED chip is disposed. 210 and the wavelength conversion layer 220 form an inverted trapezoidal structure having an upper width and a lower width. As a result, the LED substrate 210 and the wavelength conversion layer 220 have different light-emitting areas and the same light-emitting area, and the area of the light-emitting surface 222 and the area of the top surface 212 of the wafer are appropriately controlled, and the top surface 212 of the wafer can be maintained. The light is evenly distributed to the light exit surface 222 of the wavelength conversion layer 220 to achieve the effect of reducing color separation.

The wavelength conversion layer and the light-emitting diode wafer of the invention have similar light-emitting areas, and the light-emitting areas of the wavelength conversion layer and the light-emitting diode wafer are limited by the reflection layer, so that light of two different wavelength bands has similar light-emitting areas. With the light-emitting area, the light of the two different bands can be mixed to produce a relatively uniform and broad spectrum of light emission, which reduces the phenomenon of color separation.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention, and those skilled in the art can In the scope of the invention, the scope of the invention is defined by the scope of the appended claims.

100‧‧‧Flip-chip LED package

200‧‧‧Light source body

202‧‧‧Light source side surface

210‧‧‧Light Emitter Wafer

212‧‧‧Top surface of the wafer

214‧‧‧ wafer bottom

216‧‧‧ wafer side surface

218‧‧‧ electrodes

220‧‧‧wavelength conversion layer

222‧‧‧Glossy

224‧‧‧wavelength conversion layer side surface

300‧‧‧reflective layer

302‧‧‧Upper surface

Claims (9)

A flip-chip LED package comprising: a light source body, the light source body comprising: a light emitting diode chip having a top surface of the wafer, a bottom surface of the wafer, and a top surface of the wafer and a bottom surface of the wafer And surrounding the wafer side surface of the light emitting diode chip, the light emitting diode chip has two electrodes disposed on the bottom surface of the wafer; and a wavelength conversion layer correspondingly disposed on the top surface of the wafer, having a light emitting surface and a a side surface of the wavelength conversion layer surrounding the wavelength conversion layer, wherein the wafer side surface and the wavelength conversion layer side surface are defined as a light source body side surface; and a reflective layer surrounding and covering the light source body side surface and exposed The light emitting surface and the two electrodes. The flip-chip LED package of claim 1, wherein the reflective layer comprises ceria and tantalum or a resin. The flip-chip LED package of claim 2, wherein the wavelength conversion layer is an encapsulant comprising a wavelength converting substance. The flip-chip LED package of claim 3, wherein the wavelength converting material is one of a phosphor powder, a pigment or a pigment or a combination thereof. The flip-chip LED package of claim 1, wherein the upper surface of the reflective layer is flush with the light-emitting surface of the wavelength conversion layer. A method for fabricating a flip-chip light-emitting diode package, comprising: providing a light-emitting diode wafer having a first surface and a second surface on the opposite side; forming an epitaxial structure layer on the first a surface; forming a plurality of electrodes on the surface of the epitaxial structure layer; forming a wavelength conversion material layer on the second surface; and dicing the epitaxial light-emitting diode wafer to form a plurality of light source bodies, each of the light source bodies The invention comprises: a light emitting diode chip formed by the epitaxial structure layer, having a top surface of the wafer, a bottom surface of the wafer, and a wafer side surface adjacent to the top surface of the wafer and the bottom surface of the wafer and surrounding the light emitting diode chip a wavelength conversion layer formed by the wavelength conversion material layer is formed on a top surface of the wafer, the wavelength conversion layer has a light emitting surface and a wavelength conversion layer side surface surrounding the wavelength conversion layer; and a pair of electrodes, Formed on the bottom surface of the wafer; wherein the wafer side surface and the wavelength conversion layer side surface are defined as a light source body side surface; an adhesive layer is provided, and the bottom surface of each of the light source bodies is fixed to the paste Layer; forming a layer of reflective material covers and surrounds the plurality of light source body; Polishing the reflective material layer to expose the light-emitting surface on each of the light source bodies; performing a cutting process on the reflective material layer to form a plurality of light-emitting diode packages spaced apart from each other, and each of the light-emitting diode packages includes a light source body and the reflective material layer coated on a side surface of the light source body; and removing the adhesive layer to form a plurality of light emitting diode packages. The method of manufacturing a flip-chip type light emitting diode package according to claim 6, wherein the reflective material layer comprises cerium oxide and tantalum or a resin. The method for manufacturing a flip-chip type LED package according to claim 7, wherein the wavelength conversion layer is an encapsulant containing a wavelength converting substance. The method for producing a flip-chip type light emitting diode package according to claim 8, wherein the wavelength converting substance is one of a phosphor powder, a pigment or a pigment or a combination thereof.