CN102820410B - Packaging structure of light-emitting elements - Google Patents

Abstract

The present invention discloses a structure of a light-emitting element, comprising: a transparent substrate having a first plane and a second plane; a light-emitting element disposed on the first plane and emitting light through the second plane; and a carrier connected to an end of the transparent substrate extending beyond the light-emitting structure through a connecting material, and the angle between the carrier and the first plane is approximately 45-135 degrees.

Description

Packaging structure of light-emitting elements

This application document is a divisional application of the invention patent application No. 200810003224.2 filed on January 28, 2008, with the title of "Packaging Structure of Light-Emitting Elements".

technical field

The invention relates to a packaging structure of a light emitting element.

Background technique

Generally, light-emitting diodes (Light-Emitting Diodes; LEDs) with transparent substrates can be divided into face-up type and flip-chip type. Among them, the vertical LED is fixed on the carrier by glue or metal, and the flip-chip LED is bonded by metal or solder. The main fixing surface is the forward light-emitting surface of the LED or its parallel surface. Since the light emitting layer of the light emitting diode emits light at 360 degrees, the downward emitting light is generally reflected back to the forward light emitting surface through the reflective surface or emitted through the transparent substrate. However, the thickness of the transparent substrate should not be too thick, so as to avoid weakening of the light intensity. In addition, when the size of the light-emitting diode is larger, more reflected light will pass through the multiquantum well structure (MultiQuantum Well, MQW) in the light-emitting layer, and the light extraction efficiency will decrease due to the light absorption effect.

Fig. 1 is a package structure of a traditional light-emitting element. As shown in the figure, the fixing surface 1 is a plane on which the LED chip 100 is fixed on the carrier 3 , and this plane is parallel to the forward light-emitting surface 4 of the LED chip 100 . The downward light is reflected back to the forward light emitting surface 4 or the side light emitting surface 5 by a reflective surface 2 . The disadvantage of this packaging method is that when the size of the light emitting diode chip is larger, more reflected light passes through the multiple quantum well structure in the light emitting layer, and the light extraction efficiency is reduced due to the light absorption effect.

Contents of the invention

The invention provides a packaging structure of a light-emitting element, which includes a light-emitting element and a carrier. Wherein the light-emitting element is fixed on a transparent substrate, and the light-emitting element is connected to a carrier through a connecting material, wherein the included angle between the first plane of the transparent substrate and the carrier is not equal to zero. In a preferred embodiment, the included angle between the first plane of the transparent substrate and the carrier is about 45-135 degrees, more preferably about 90 degrees.

The present invention provides a packaging structure of light-emitting elements. At least one light-emitting element is packaged sideways so that the bottom of the element becomes an effective light-emitting surface that is easier to emit light. In this way, not only can the absorption of the light emitting layer be reduced, but also the light extraction efficiency can be greatly improved.

The present invention provides a package structure of a light-emitting element, using a connecting material to connect at least one light-emitting element fixed on a transparent substrate to a carrier, wherein the included angle between the first plane of the transparent substrate and the carrier is not equal to zero degrees. In a preferred embodiment, the included angle between the first plane of the transparent substrate and the carrier is about 45-135 degrees, more preferably about 90 degrees. In addition, a diffuser is added to the packaging structure, so that the light is scattered (Scattering) due to the scattering material, and then the light is emitted from a single side, thereby forming a packaging structure of a side-emitting light-emitting element.

The invention provides an application of a light-emitting element packaging structure, in which a plurality of light-emitting element packaging structures are connected to a carrier with a reflective layer by using a connecting material. When multiple packaging structures are designed with thin film materials with different functional requirements, it can be applied to the backlight source of the liquid crystal display.

The present invention provides an application of a light-emitting element packaging structure. The light emitted by a plurality of side-emitting light-emitting element packaging structures is introduced into a light guide plate, wherein the downward light is reflected back into the light guide plate through a reflective layer, and finally All the light is emitted through the thin film material, which can be applied to the backlight source of the liquid crystal display.

Description of drawings

Figure 1 shows the traditional packaging method of light-emitting elements;

Fig. 2 is a side view showing the structure of the LED chip used in the present invention;

Fig. 3 is a side view showing the structure of another LED chip used in the present invention;

Figure 4 is a side view showing the structure of the light emitting element used in the present invention;

5 is a side view showing the structure of another light-emitting element used in the present invention;

6 is a side view showing a package structure of a light emitting element according to an embodiment of the present invention;

7 is a side view showing the package structure of a side-emitting light-emitting element according to another embodiment of the present invention;

Fig. 8 is a side view showing the design structure of an embodiment of the present invention applied to a liquid crystal display backlight;

FIG. 9 is a side view showing another design structure of an embodiment of the present invention applied to a backlight source of a liquid crystal display.

Explanation of reference signs:

1~fixed surface

2~ reflective surface

3~carrier

4~Positive light-emitting surface

5~ side light emitting surface

10, 20~ Light-emitting element packaging structure

30, 40~ The packaging structure of light-emitting elements of liquid crystal display backlight

100, 200, 300~ LED chips

400, 500~ light emitting elements

201, 301~ growth substrate

202, 302~ epitaxial structure

202a, 302a ~ the first conductive semiconductor

202b, 302b~active layer

202c, 302c ~ the second conductive semiconductor

203, 303, 403, 503, 606, 607~ electrode

404~transparent substrate

404a~The first plane of the transparent substrate

404b~Second plane of transparent substrate

504~Light-transmitting substrate containing phosphor powder

505~ phosphor layer

601, 701, 801, 902~ carrier

602, 703, 802, 901~ reflective layer

603～platform

604~lens

605, 704, 804~ connection material

702~ Scattering Matter

803, 903～film materials

902~ Polarizing plate

Detailed ways

The invention discloses a packaging structure of a light-emitting element and a manufacturing method thereof. In order to make the description of the present invention more detailed and complete, reference may be made to the following description together with the illustrations in FIGS. 2 to 9 .

2-3 are LED chips used in embodiments of the present invention. As shown in FIG. 2, the structure is to grow an epitaxial structure 202 on a growth substrate 201 by, for example, metal organic chemical vapor deposition (MOCVD), wherein the epitaxial structure at least includes a first conductive semiconductor layer 202a, an active layer 202b and A second conductive semiconductor layer 202c, and then form an electrode 203 on the epitaxial structure 202 to form a light emitting diode chip 200 .

As shown in FIG. 3 , the structure is to grow an epitaxial structure 302 on a growth substrate 301 by, for example, metal organic chemical vapor deposition (MOCVD), wherein the epitaxial structure at least includes a first conductive semiconductor layer 302a and an active layer 302b and a second conductive semiconductor layer 302c; and then etch part of the epitaxial structure 302 to a part of the growth substrate from top to bottom, and then form an electrode 303 on the epitaxial structure 302 to form a light emitting diode chip 300.

FIG. 4 is a schematic diagram of a light emitting device 400 . The light emitting diode chip such as 200 or 300 is placed on the first plane 404 a of a transparent substrate 404 to form a light emitting element 400 . Taking the structure of the LED chip 200 as an example, the structure includes a growth substrate 201; an epitaxial structure 202 is formed on the growth substrate 201, wherein the epitaxial structure at least includes a first conductive semiconductor layer 202a, an active layer 202b and a first Two conductive semiconductor layers 202c; and an electrode 203 are formed on the epitaxial structure 202.

FIG. 5 is a schematic diagram of a light emitting device 500 . A light-emitting diode chip with the same structure as the light-emitting diode chip 200 or 300 is placed on a transparent substrate 504 containing fluorescent powder to form a light-emitting element 500 . Taking the structure of the LED chip 200 as an example, the structure includes a growth substrate 201; an epitaxial structure 202 is formed on the growth substrate 201, wherein the epitaxial structure at least includes a first conductive semiconductor layer 202a, an active layer 202b and a first Two conductive semiconductor layers 202c; and an electrode 203 are formed on the epitaxial structure 202. Next, a phosphor layer 505 is covered on and around the LED chip 200 to form a light emitting element 500 .

FIG. 6 is a structural side view of the first embodiment of the packaging structure of the present invention. The aforementioned structures of the light-emitting element 400 or 500 can be used in each embodiment of the packaging structure of the present invention, and to avoid repetition, only the light-emitting element 400 is used as a representative. As shown in FIG. 6, a carrier 601 having a reflective inner wall 602 uses a connecting material 605 to connect the transparent substrate 404 of the light-emitting element 400 to the platform 603 of the carrier 601, wherein the first plane 404a of the transparent substrate and its parallel The surface (the second plane 404b ) stands on the platform. Preferably, the transparent substrate is substantially perpendicular to the platform of the carrier. In addition, the p-electrode and n-electrode of the light-emitting diode are electrically connected to the p-electrode 606 and n-electrode 607 of the carrier respectively, forming a packaging structure 10 of a light-emitting diode. The light emitting direction generated by the active layer of the light emitting diode chip is omnidirectional (omnidirectional), wherein the light incident on the first plane 404a of the transparent substrate will pass through the transparent substrate and be emitted from the second plane 404b of the transparent substrate, After being reflected by the inner wall 602 of the reflective surface of the carrier, it leaves the package structure 10 . In addition, a lens (lens) 604 can be added above the entire package structure 10 to increase the light extraction efficiency of the entire package structure.

FIG. 7 is a structural side view of the second embodiment of the packaging structure of the present invention. The carrier 701 has a reflective surface 703 , and the transparent substrate 404 of the light-emitting element 400 is stood on the carrier 701 with a connecting material 704 , preferably, it is substantially perpendicular to the carrier 701 . The p/n electrodes of the light emitting diodes are electrically connected to the p/n electrodes of the carrier respectively, and the inside of the packaging structure is filled with diffusers 702, so that the light generated by the light emitting elements is scattered by the diffusers. Finally, all the light (as shown by the arrow in the figure) penetrates the transparent substrate 404 and exits from the second plane 404b, becoming the encapsulation structure 20 of the side-emitting light-emitting element.

FIG. 8 is a side view of a design structure 30 applied to a liquid crystal display backlight according to an embodiment of the present invention. The bottom of the carrier 801 has a reflective layer 802, and the packaging structure 10 of multiple light-emitting elements is connected in the carrier 801 by using a connecting material 804, and the p/n electrodes of the light-emitting diodes are respectively electrically connected with the p/n electrodes of the carrier, wherein each The packaging structure and method of a light-emitting element are the same as those in FIG. 6 above, and will not be repeated here. When the light emitted by the packaging structure of multiple light-emitting elements is designed to uniformly emit the required mixed light through the design of thin film materials 803 with different functions (such as: prism sheet, Prism Sheet), it can be used as the structure 30 of the LCD backlight.

FIG. 9 is a schematic diagram of another design structure 40 and a polarizer 902 applied to a backlight source of a liquid crystal display according to an embodiment of the present invention. A polarizer (Polarizer) 902 with a reflective layer 901 on the bottom, and a film material 903 on the top layer. After matching the liquid crystal display backlight 40 composed of a plurality of packages 20 of side-emitting light-emitting elements, the side light emitted by the backlight 40 is guided into the polarizer 902 (as shown by the arrow in the figure), and the downward The light is reflected back into the polarizer through the reflective layer 901 , and finally all the light is mixed and polarized and emitted from the film material 903 , and then enters other structures of the liquid crystal display (such as the liquid crystal layer). The light traveling direction is shown by the arrow.

Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art may make various modifications and modifications without departing from the spirit and scope of the present invention. Therefore The protection scope of the present invention should be defined by the appended claims.

Claims (9)

1. A structure of a light-emitting element, comprising: a transparent substrate having a first plane and a second plane; A light-emitting diode chip, including a substrate and an epitaxial structure, is disposed on the first plane, and emits light through the second plane; and The carrier is connected to the end of the transparent substrate beyond the light-emitting diode chip through the connection material so that the light-emitting diode chip does not contact the carrier, and the included angle between the carrier and the first plane is 45-135 degrees. 2. The light emitting device structure according to claim 1, wherein the carrier is electrically connected to the light emitting diode chip. 3. The light-emitting element structure according to claim 1, wherein the light-emitting diode chip has an active layer, and the area of the first plane is not smaller than the area of the active layer. 4. The structure of the light-emitting device as claimed in claim 1, wherein the angle between the carrier and the first plane is about 90 degrees. 5. The structure of the light-emitting device as claimed in claim 1, wherein the transparent substrate comprises fluorescent powder. 6. The structure of the light emitting device as claimed in claim 1, wherein the light emitting diode chip comprises a phosphor layer. 7. The light emitting device structure as claimed in claim 1, wherein the light generated by the light emitting diode chip is omnidirectional. 8. The light-emitting element structure according to claim 1, wherein the carrier comprises a reflective layer. 9. The light-emitting element structure according to claim 1, further comprising a lens.