TW201409762A - LED package - Google Patents

Abstract

An LED package includes a substrate, at least two electrodes, and an LED chip. The substrate includes an upper surface and a bottom surface opposite to the upper surface. The at least two electrodes are formed on the substrate. The LED chip is electrically connected to the at least two electrodes. The LED package further includes a light-wavelength conversion layer. The light-wavelength conversion layer covers the LED chip on the substrate. The light-wavelength conversion layer includes at least two photonic crystal structures. Each photonic crystal structure has a different period.

Description

Light emitting diode package structure

The present invention relates to semiconductor structures, and more particularly to a light emitting diode package structure.

Compared with the traditional illumination source, the Light Emitting Diode (LED) has the advantages of light weight, small volume, low pollution and long life. It has been widely used as a new type of illumination source. .

The conventional light-emitting diode package structure emits white light using a structure of a monochromatic light-emitting diode die with a phosphor powder. However, when the light-emitting diode package structure of the structure is used as a backlight module, the structure of the monochromatic light-emitting diode die and the phosphor powder produces white light, and the display performance is not high. The contrast of the colors is lower. Therefore, how to improve the color representation of the LED package structure applied to the backlight module has become a problem that the industry has been exploring.

In view of this, it is necessary to provide a light-emitting diode package structure with high color representation.

A light emitting diode package structure comprising a substrate, an electrode and a light emitting diode chip, the substrate comprising an upper surface and a lower surface opposite to the upper surface, the electrodes are at least two, and the electrode is formed on the substrate The light-emitting diode chip is electrically connected to the electrode, and further includes a light wave conversion layer covering the light-emitting diode chip on the substrate, wherein the light wave conversion layer is at least two layers of photonic crystal structures, and each layer Photonic crystal structures have different spacings.

In the above-mentioned light-emitting diode package structure, since photonic crystal grains with different pitches are used as a multilayer light wave conversion layer to cover the light-emitting diode wafer, the photonic crystals with different pitches can convert the original wavelength of the light into different wavelengths. Therefore, light rays passing through different layers of the light wave conversion layer can be light of different wavelengths, so that the package structure of the monochromatic light-emitting diode chip can emit light having more wavelength types, thereby widening the wavelength range and improving Color performance and improved light color contrast.

The invention will now be further described with reference to the specific embodiments thereof with reference to the accompanying drawings.

Referring to FIG. 1 and FIG. 2 , a light emitting diode package structure 10 according to a first embodiment of the present invention includes a substrate 11 , an electrode 12 , a light emitting diode chip 13 , and a light wave conversion layer 14 .

The substrate 11 includes opposing upper and lower surfaces 111, 112. The substrate 11 includes two opposite first sides 113 and two opposite second sides 114. The first side 113 and the second side 114 are rectangular. In this embodiment, the material of the substrate 11 is PPA or the like. It can be understood that the lengths of the sides of the substrate 11 may be the same or different. Further, the shape of the substrate 11 is not limited to a rectangle, and the shape may also be a circle or the like.

The electrodes 12 are at least two, and the electrodes 12 are formed on the substrate 11 and extend from the upper surface 111 in the direction of the first side 113 around the second side 114 to the lower surface 112. The two electrodes 12 are electrically insulated from each other. The material used for the electrode 12 is a metal material having good electrical conductivity, such as an alloy of one or more of gold, silver, copper, platinum, aluminum, nickel, tin or magnesium.

The LED chip 13 is fixed on the substrate 11 and electrically connected to the electrode 12 . In the present embodiment, the light-emitting diode chip 13 is a light source that emits light in a single color. The LED chip 13 is placed on one of the electrodes 12 and is connected to the two electrodes 12 by a metal wire 131. In other embodiments, the LED wafer 13 can also be fixed on the electrode 12 by a flip chip and electrically connected to the electrode 12.

The light wave conversion layer 14 covers the light emitting diode wafer 13 and is further formed on the substrate 11. The light wave conversion layer 14 is a photonic crystal structure. The photonic crystal structure is a nano-scale structure, and the photonic crystal is a material which periodically exhibits a low refractive index (such as an artificial air cavity) at certain positions of the high refractive index material, and a periodically occurring low refractive index The spacing between the materials can be adjusted during the formation of the photonic crystal to form photonic crystal materials having different pitches. Photonic crystals with different pitches form band gaps of different widths, so that light having original wavelengths transmitted through photonic crystals of different pitches can be converted into light different from the original wavelength, thereby exhibiting different colors. When the light emitted by the LED chip 13 is directed toward the light wave conversion layer 14, the light is adjusted by the band gap of the photonic crystal and absorbs, diffracts or refracts, thereby converting the original wavelength of the light into another wavelength. The effect is that the color appears in another color.

The light wave conversion layer 14 includes at least a two-layer structure which is stacked from the upper surface 111 of the substrate 11 toward the substrate 11 and away from the substrate 11. The photonic grain structure of the at least two layer structure has different pitches. In the present embodiment, the light wave conversion layer 14 includes a three-layer structure, which is a first light wave conversion layer 141, a second light wave conversion layer 142, and a third light wave conversion layer 143, respectively. The first light wave conversion layer 141 is laid on the upper surface 111 of the substrate 11 and covers the light emitting diode chip 13 and the metal wires 131. The second light wave conversion layer 142 is superposed on the first light wave conversion layer 141, and the third light wave conversion layer 143 is superposed on the second light wave conversion layer 142. The photonic grain structures of the three-layer light wave conversion layers 141, 142, and 143 have different pitches, respectively. The light emitted by the LED chip 13 sequentially passes through the three layers of the light wave conversion layers 141, 142, and 143 to generate light of three different wavelength ranges, and the light of the three wavelength ranges is mixed to form a wider wavelength range. Light, which increases the color performance of the light and increases the contrast of the color.

In the present embodiment, the pitch of the photonic crystal of the first light wave conversion layer 141 is 180 nanometers (nm), and the light emitted by the light-emitting diode wafer 13 passes through the first light wave conversion layer 141 and is converted into light having a blue light band. Blue light is generated; the photonic crystal of the second light wave conversion layer 142 has a pitch of 210 nanometers (nm), and the light emitted from the light-emitting diode chip 13 passes through the second light wave conversion layer 142 and is converted into light having a green light band to generate green light. The light photonic crystal of the third light wave conversion layer 143 has a pitch of 300 nanometers (nm), and the light emitted from the light-emitting diode chip 13 passes through the third light wave conversion layer 143 and is converted into light having a red light band to generate red light. .

A reflective cup 15 may be formed on the substrate 11 of the light emitting diode package structure 10 on the substrate 11. The reflector cup 15 surrounds the first side 113 and the second side 114 of the substrate 11 to surround the light-emitting diode chip 13 in the reflective cup 15. The light wave conversion layer 14 is housed in a space surrounded by the reflective cup 15.

Referring to FIG. 3 and FIG. 4 , a light emitting diode package structure 20 according to a second embodiment of the present invention includes a substrate 11 , an electrode 12 , a light emitting diode chip 13 , and a light wave conversion layer 24 . The light emitting diode package structure 20 in the present embodiment is different from the light emitting diode package structure 10 in the first embodiment in that the light wave conversion layer 24 has different structural arrangements. In the present embodiment, the light wave conversion layer 24 is divided into a plurality of regions to cover the substrate 11. Specifically, the light wave conversion layer 24 includes a first light wave conversion layer 241, a second light wave conversion layer 242, a third light wave conversion layer 243, and a fourth light wave conversion layer 244, and the pitches of the four light wave conversion layers are different. In the present embodiment, the four light wave conversion layers divide the upper surface 111 of the substrate 11 into four equal-area regions, each of which covers an equal-area region of the upper surface 111 of the substrate 11. The light emitted by the LED chip 13 is uniformly diffused into each of the light wave conversion layers and then converted into light of another wavelength, thereby widening the wavelength range of the light finally emitted by the LED package structure 20, thereby making the light The color performance is improved and the contrast of the color is increased. Of course, the light wave conversion layer in this embodiment can also be divided into two, three, five, six, and the like. In other embodiments, the four light wave conversion layers can divide the upper surface 111 of the substrate 11 into four regions of unequal area, so that the light emitted by the LED wafer 13 is directed to the light of a certain light wave conversion layer. More or less to meet different needs.

Referring to FIG. 5 and FIG. 6 , a light emitting diode package structure 30 according to a third embodiment of the present invention includes a substrate 11 , an electrode 12 , a light emitting diode chip 13 , and a light wave conversion layer 34 . The light emitting diode package structure 30 of the present embodiment is different from the light emitting diode package structures 10 and 20 of the first and second embodiments in that the light wave conversion layer 34 has a different arrangement. The light wave conversion layer 34 in the present embodiment is divided into a plurality of regions and layered on the substrate 11. Specifically, the light wave conversion layer 34 includes a first light wave conversion layer 341, a second light wave conversion layer 342, a third light wave conversion layer 343, and a fourth light wave conversion layer 344, and the pitches of the four light wave conversion layers are different. The four light wave conversion layers divide the upper surface 111 of the substrate 11 into four regions, each of which is self-covered on a respective region of the upper surface 111 of the substrate 11. Each of the light wave conversion layers is further divided into a plurality of layers of stacked sheets from the upper surface 111 of the substrate 11 in a direction away from the substrate 11. Taking the first light wave conversion layer 341 as an example. The first light wave conversion layer 341 includes a lower layer 3411, a middle layer 3412, and an upper layer 3413. The lower layer 3411 is laid directly over and covers the upper surface 111 of the substrate 11, the middle layer 3412 is folded over the lower layer 3411, and the upper layer 3413 is overlaid on the middle layer 3412. Therefore, the present embodiment corresponds to an arrangement in which the light wave conversion layers in the first embodiment and the second embodiment are assembled. The light emitted by the LED chip 13 is uniformly diffused into the light wave conversion layer of each region and then further directed to the multilayer light wave conversion layer in each region, and then converted into light of different wavelengths, thereby encapsulating the light emitting diode. The wavelength range of the resulting light from the structure 30 is widened, thereby increasing the color representation of the light and increasing the contrast of the color.

In the LED package structure provided by the embodiment of the present invention, photonic crystal grains with different pitches are used as a multilayer light wave conversion layer to cover the LED substrate, and photonic crystals with different pitches can convert the original wavelength of the light into Different wavelengths of light, so that light rays passing through different layers of the light wave conversion layer can emit light of different wavelengths, thereby converting the light emitted by the light emitting diode package structure into light of various wavelength regions, thereby increasing the wavelength range. Wide, improves color performance and improves light color contrast.

In summary, the present invention has indeed met the requirements of the invention patent, and has filed a patent application according to law. However, the above description is only a preferred embodiment of the present invention, and it is not possible to limit the scope of the patent application of the present invention. Equivalent modifications or variations made by persons skilled in the art in light of the spirit of the invention are intended to be included within the scope of the following claims.

10, 20, 30. . . Light emitting diode package structure

11. . . Substrate

111. . . Upper surface

112. . . lower surface

113. . . First side

114. . . Second side

12. . . electrode

13. . . Light-emitting diode chip

131. . . Metal wire

14, 24, 34. . . Light wave transition layer

15. . . Reflective cup

141, 241, 341. . . First light wave transition layer

142, 242, 342. . . Second light wave transition layer

143, 243, 343. . . Third light wave transition layer

244, 344. . . Fourth light wave transition layer

3411. . . Lower layer

3412. . . Middle layer

3413. . . upper layer

FIG. 1 is a cross-sectional view showing a light emitting diode package structure according to a first embodiment of the present invention.

2 is a top plan view of the light emitting diode package structure of FIG. 1.

3 is a cross-sectional view showing a light emitting diode package structure according to a second embodiment of the present invention.

4 is a top plan view of the light emitting diode package structure of FIG. 3.

FIG. 5 is a cross-sectional view showing a light emitting diode package structure according to a third embodiment of the present invention.

6 is a top plan view of the light emitting diode package structure of FIG. 5.

10. . . Light emitting diode package structure

11. . . Substrate

111. . . Upper surface

112. . . lower surface

12. . . electrode

13. . . Light-emitting diode chip

131. . . Metal wire

14. . . Light wave transition layer

141. . . First light wave transition layer

142. . . Second light wave transition layer

143. . . Third light wave transition layer

15. . . Reflective cup

Claims (10)

A light emitting diode package structure comprising a substrate, an electrode and a light emitting diode chip, the substrate comprising an upper surface and a lower surface opposite to the upper surface, the electrodes are at least two, and the electrode is formed on the substrate The light-emitting diode chip is electrically connected to the electrode, and the improvement is characterized by further comprising: a light wave conversion layer covering the light-emitting diode chip on the substrate, wherein the light wave conversion layer is at least two layers of photons Crystal structure, each layer of photonic crystal structure has different spacing. The light emitting diode package structure according to claim 1, wherein the at least two light wave conversion layers are stacked from an upper surface of the substrate in a direction away from the substrate. The light emitting diode package structure of claim 2, wherein the at least two light wave conversion layers comprise a first light wave conversion layer, a second light wave conversion layer, and a third light wave conversion layer, the first light wave The transition layer is laid on the upper surface of the substrate, and the light emitting diode wafer is covered in the first light wave conversion layer, the second light wave transition is laminated on the first light wave conversion layer, and the third light wave transition is laminated on the second light wave. Grab the transition layer. The light emitting diode package structure according to claim 3, wherein a pitch of the photonic crystal structure of the first light wave conversion layer is 180 nm, and a pitch of the photonic crystal structure of the second light wave conversion layer is 210. The spacing of the photonic crystal structure of the third light wave transition layer is 300 nm. The light emitting diode package structure of claim 1, wherein the at least two light wave conversion layers cover different regions of the upper surface of the substrate. The light emitting diode package structure according to claim 5, wherein the at least two light wave conversion layers divide the upper surface of the substrate into at least two regions, and each of the light wave conversion layers covers the substrate An area of equal surface area. The light emitting diode package structure of claim 6, wherein each of the at least two layers of the light wave conversion layer comprises at least a two-layer photonic crystal structure. The light emitting diode package structure of claim 7, wherein each of the at least two layers of the light wave conversion layer comprises a lower layer, a middle layer and an upper layer, the lower layer covering one of the upper surfaces of the substrate In the region, the middle layer is superposed on the lower layer, and the upper layer is superposed on the middle layer. The light emitting diode package structure according to any one of claims 1 to 8, wherein the light emitting diode chip is a light source that emits light in a single color. The light emitting diode package structure of claim 1, further comprising a reflective cup formed on an upper surface of the substrate and surrounding the light emitting diode wafer in the reflective cup, the light wave The transition layer is placed in the space formed by the reflector cup.