TWI433360B - White light emitting diode structure and manufacturing method thereof - Google Patents

Description

White light emitting diode structure and manufacturing method thereof

The invention relates to a technology for changing the light direction of a light-emitting diode, uniformly exciting the phosphor powder on the light-emitting diode, and producing a uniform light-emitting white light-emitting diode, in particular, a white light-emitting diode structure. And its manufacturing method.

Light-emitting diode system A semiconductor component that emits a luminescent light beam, and is currently mostly used for indicator lights, display panels, and the like. A simple light-emitting diode can only emit pure color light of various colors. In order to emit white light, it is necessary to use a method of mixing fluorescent powder to produce a white light emitting diode. The light-emitting diode has the advantages of high efficiency, long life, not easy to break, and energy saving and environmental protection.

At present, a general white light emitting diode manufacturing method is to spray the light emitting diode 34 of the fluorescent powder 36. As shown in FIG. 1A, the light emitting diode wafer 34 and the substrate 32 are vertically cut directly from above, and then lighted. The light-emitting diode wafer 34 excites the phosphor powder 36 on the surface of the light-emitting diode wafer 34. However, as shown in FIG. 1B, the light of the light-emitting diode wafer 34 is emitted from the side of the substrate 32, causing light to be reflected. Uniform, so the encapsulated white light-emitting diodes will exhibit different shades of light at different viewing angles.

In view of the above, the present invention is directed to the above problems, and provides a white light emitting diode structure and a manufacturing method thereof to effectively solve the conventional problems.

The main object of the present invention is to provide a white light emitting diode structure and a manufacturing method thereof, which are characterized in that the shape of the substrate is changed and a reflective layer is plated on the outer layer of the substrate, the angle of light reflection can be changed, and the light emitting diode wafer can be uniformly excited. The phosphor powder allows the light-emitting diode to emit a uniform white light.

In order to achieve the above object, the present invention provides a method for fabricating a white light emitting diode, which is provided with a substrate on which a plurality of light emitting diode chips are disposed; and a phosphor powder is sprayed on the surface of the light emitting diode wafer and exposed. a second electrode of the light-emitting diode chip; the light-emitting diode wafer is adhered to the temporary substrate by using a temporary adhesive; the bottom of the substrate is polished, and the bottom of the substrate is cut in units of the light-emitting diode to form a plurality of grooves; A reflective layer is on the surface of the substrate; the temporary adhesive is removed from the temporary substrate; and the light-emitting diode wafer is used as a unit, and the substrate is separated by the groove to become a white light-emitting diode.

In addition, the present invention also provides a white light emitting diode structure, which is a substrate having a sloped surface on each side thereof, and a reflective layer is disposed on the bottom surface of the substrate, and at least one light emitting diode is disposed on the substrate. On the wafer, the LED chip is coated with a phosphor powder on the surface of the LED chip in addition to the two electrodes.

The purpose, technical content, features and effects achieved by the present invention will be more readily understood by the detailed description of the embodiments.

The invention relates to a white light emitting diode structure and a manufacturing method thereof, which are to change the shape of a substrate of a light emitting diode chip and plate the substrate with a reflective layer to change a light refraction direction, and uniformly refract light to excite the fluorescent powder to make the white light emit light. The diode emits a uniform white light.

The structure of the white light emitting diode 10 is as shown in FIG. 2, and the present invention is composed of a substrate 12. In this embodiment, the substrate 12 is provided with a slope portion 124 from the bottom to the outside, so that the substrate 12 and the slope portion are provided. The angle of 124 forms a negative angle, wherein the angle between the substrate 12 and the inclined surface portion 124 is more acute or right angle, and the surface of the substrate 12 is provided with a light-emitting diode wafer 14 , and the surface of the light-emitting diode wafer 14 except the two electrodes 142 The phosphor powder 16 is sprayed, and the bottom of the substrate 12 and the slope portion 124 are provided with a reflective layer 22, and the material of the reflective layer 22 may be aluminum, silver, lead, platinum, aluminum alloy, silver alloy, lead alloy or platinum alloy. 3 is a schematic view of the phosphor powder 16 on the excitation light-emitting diode chip 14 of the present invention, which is applied to the two electrodes 142 to illuminate the light-emitting diode wafer 14, and the reflective layer 22 can uniformly reflect light. The light emitted by the diode chip 14 can uniformly excite the phosphor powder 16 to convert the light into white light, and the color of the phosphor powder is complementary to the color of the light emitting diode, and can be formed by using an appropriate ratio. In the white light, the phosphor powder 16 of the present embodiment is yellow in color and can be mixed with the blue light emitted from the light-emitting diode wafer 14 of the present invention to emit white light.

For the manufacturing process of the white light emitting diode, please refer to FIG. 4A to FIG. 4G. First, please refer to FIG. 4A to provide a substrate 12 on which a plurality of light emitting diode chips 14 have been fabricated. Next, as shown in FIG. 4B. As shown in the figure, the phosphor powder 16 is sprayed on the surface of the plurality of LED chips 14 to expose the two electrodes 142; as shown in FIG. 4C, the LEDs 14 are bonded by the temporary adhesive 18. On the temporary substrate 20, the material of the temporary adhesive 18 may be silver glue or wax, and the material of the temporary substrate 20 may be ceria, alumina, aluminum nitride, tantalum or niobium; As shown in FIG. 4D, the bottom of the substrate 12 is ground and thinned, and the substrate 12 is cut by a wafer cutter or laser, and a plurality of grooves 122 are cut out at the bottom of the substrate 12 in units of each of the light-emitting diode wafers 14. The recess 122 may be a V-shaped groove to partition the plurality of LEDs 14; and further, refer to FIG. 4E, a reflective layer 22 is formed on the surface of the substrate 12, wherein the reflective layer 22 may be made of aluminum or silver. , lead, platinum, aluminum alloy, silver alloy, lead alloy or platinum alloy. As shown in FIG. 4F, the temporary adhesive 18 on the light-emitting diode wafer 14 and the temporary substrate 20 are removed. Finally, the substrate 12 is separated by the recess 122 in units of the light-emitting diode wafer 14 to obtain a plurality of independent white light-emitting diodes 10. As shown in FIG. 4G, the substrate 12 and all of the light-emitting diodes thereon can be The polar body wafer 14 is moved to adhere to the blue film 24. Since the blue film 24 has ductility, the blue film 24 can be expanded, and the substrate 12 and the upper LED chip 14 are separated to obtain a plurality of images as shown in FIG. Independent white light emitting diode 10.

In view of the above, the present invention can achieve that the white light emitting diode can uniformly refract light, and the phosphor powder on the light emitting diode chip is excited, so that the white light emitting diode can emit uniform white light.

The above is only the preferred embodiment of the present invention and is not intended to limit the scope of the present invention. Therefore, any changes or modifications of the features and spirits of the present invention should be included in the scope of the present invention.

10. . . White light emitting diode

12. . . Substrate

14. . . Light-emitting diode chip

16. . . Fluorescent powder

18. . . Temporary adhesive

20. . . Temporary substrate

twenty two. . . Reflective layer

twenty four. . . Blue film

32. . . Substrate

34. . . Light-emitting diode chip

36. . . Fluorescent powder

122. . . Groove

124. . . Inclined face

126. . . bottom

142. . . electrode

Figure 1A is a schematic view of a conventional cut light emitting diode wafer.

Fig. 1B is a schematic view showing the structure of a conventional white light emitting diode.

Figure 2 is a schematic view of the structure of the present invention.

Figure 3 is a schematic view of the phosphor powder on the excitation light-emitting diode wafer of the present invention.

Fig. 4A is a schematic view showing the light emitting diode chip of the present invention on a substrate.

Fig. 4B is a schematic view showing the phosphor powder sprayed on the light-emitting diode of the present invention.

Figure 4C is a schematic view of the present invention covering a temporary adhesive and a temporary substrate.

4D is a schematic view of the cutting substrate of the present invention.

Fig. 4E is a schematic view showing the formation of a reflective layer of the present invention.

Figure 4F is a schematic illustration of the removal of a temporary adhesive and a temporary substrate of the present invention.

Figure 4G is a schematic view of a separate light-emitting diode wafer of the present invention.

10. . . White light emitting diode

12. . . Substrate

14. . . Light-emitting diode chip

16. . . Fluorescent powder

twenty two. . . Reflective layer

124. . . Inclined face

126. . . bottom

142. . . electrode

Claims (12)

A method for manufacturing a white light emitting diode includes: providing a substrate on which a plurality of light emitting diode chips are disposed; spraying the phosphor powder on the surface of the light emitting diode chip, and exposing the light emitting diode a second electrode; the temporary LED is temporarily adhered to the temporary substrate by using a temporary adhesive; the bottom of the substrate is ground and thinned, and the bottom of the substrate is cut in units of the light emitting diode to form a plurality of concave Forming a reflective layer on the surface of the substrate; removing the temporary adhesive and the temporary substrate; and the light emitting diode wafer as a unit, separating the substrate by using the recess to obtain a plurality of independent white light emitting diodes Polar body. The method of manufacturing a white light emitting diode according to claim 1, wherein the groove is a V-shaped groove. The method of manufacturing a white light emitting diode according to claim 1, wherein separating the light emitting diode chip is to move the light emitting diode wafer onto a blue film, and expanding the blue film to separate the white light emitting light Polar body. The method for producing a white light emitting diode according to claim 1, wherein the temporary adhesive is a silver paste or a wax. The method for manufacturing a white light emitting diode according to claim 1, wherein the material of the temporary substrate is ceria, alumina, aluminum nitride, tantalum or niobium. A method of manufacturing a white light emitting diode according to claim 1, wherein the substrate is cut by a wafer cutter or laser when the bottom of the substrate is cut. The method of manufacturing the white light emitting diode of claim 1, wherein the reflective layer is made of aluminum, silver, lead, platinum, aluminum alloy, silver alloy, lead alloy or platinum alloy. A white light emitting diode structure comprises: a substrate, each side of which is provided with a slope portion; at least one light emitting diode chip is disposed on the substrate; and a phosphor powder is located on the light emitting diode chip a surface and exposing the two electrodes of the light emitting diode; and a reflective layer located at the bottom of the substrate and the slope portion. The white light emitting diode structure of claim 8, wherein the slope portion is a slope from the bottom to the outside. The white light emitting diode structure of claim 8, wherein the reflective layer is made of aluminum, silver, lead, platinum, aluminum alloy, silver alloy, lead alloy or platinum alloy. The white light emitting diode structure according to claim 8, wherein after the voltage is applied to the electrode, the light emitting diode is illuminated to excite the fluorescent powder to convert the light into white light. The white light emitting diode structure according to claim 11, wherein the fluorescent powder is yellow, and the light of the light emitting diode is blue light, and the fluorescent powder is mixed with the blue light to emit white light.