TWI420702B - Led chip, method for manufacturing the same and backlight module using the same - Google Patents

Description

Light-emitting diode die and manufacturing method thereof, backlight module

The invention relates to a light-emitting diode die and a manufacturing method thereof, and a backlight module using the same.

A Light Emitting Diode (LED) is a semiconductor component that converts current into light of a specific wavelength range. The light-emitting diode is widely used in the field of illumination because of its high brightness, low operating voltage, low power consumption, easy matching with integrated circuits, simple driving, and long life.

Conventional light-emitting diode dies typically include a substrate and a semiconductor light-emitting structure grown on the surface of the substrate. The semiconductor light-emitting structure mainly emits light toward the front surface thereof, so that the light-emitting diode grains obtain more light in the direction opposite to the direction, and the light-emitting diode grains receive less light and less light intensity. In some work situations, such as a backlight module using a light-emitting diode die, it is often required that the light output of the light-emitting diode die is uniform, that is, the lateral light intensity of the light-emitting diode die needs to be strengthened. Generally, the light-emitting effect is changed by adding a lens to the light-emitting diode die. However, this method also brings about an increase in the process and production cost, and increases the overall volume of the light-emitting diode crystal grains, which is disadvantageous for subsequent use of the product.

A light-emitting diode die includes a substrate, a first semiconductor layer formed on the substrate, a light-emitting layer formed on the first semiconductor layer, a second semiconductor layer formed on the light-emitting layer, and disposed on the first semiconductor layer a first electrode and a second electrode disposed on the second semiconductor layer, wherein the surface of the first semiconductor layer away from the substrate comprises a first region and a second region surrounding the first region, the light emitting layer and the second semiconductor layer And the second electrode is sequentially formed on the second region, the first electrode is formed on the first region, and the top of the first electrode is higher than the surface of the light-emitting layer away from the substrate, such that the light-emitting layer is emitted toward the first electrode The light is reflected by the first electrode and is emitted toward the outer side of the light-emitting diode die.

A method for fabricating a light-emitting diode die includes the steps of: providing a substrate; forming a first semiconductor layer on the substrate; forming a first region on the surface of the first semiconductor layer away from the substrate; and surrounding the first region a second region; a light emitting layer and a second semiconductor layer are sequentially formed on the second region of the first semiconductor; a first electrode is disposed on the first region of the first semiconductor layer and electrically connected to the first semiconductor layer, wherein the The top of the first electrode is at least higher than the surface of the luminescent layer away from the substrate; and the second electrode is disposed on the second semiconductor layer.

A backlight module includes a base, a plurality of light emitting diode modules disposed on the base, and a light guide plate disposed above the light emitting diode module, wherein the light emitting diode module includes a light emitting diode die. The light emitting diode die includes a substrate, a first semiconductor layer formed on the substrate, a light emitting layer formed on the first semiconductor layer, a second semiconductor layer formed on the light emitting layer, and disposed on the first semiconductor layer a first electrode and a second electrode disposed on the second semiconductor layer, wherein the surface of the first semiconductor layer away from the substrate includes a first region and a second region surrounding the first region, the light emitting layer, the second semiconductor layer, and a second electrode is sequentially formed on the second region, the first electrode is formed on the first region, and a top of the first electrode is higher than a surface of the light emitting layer away from the substrate, such that the light emitting layer is emitted toward the first electrode The light is reflected by the first electrode and is emitted toward the outside of the light-emitting diode die.

The light-emitting diode of the present invention is in use, and the light emitted from the light-emitting layer toward the first electrode is emitted toward the outer side of the light-emitting diode die through the reflection of the first electrode, so that the light is emitted by the first electrode. The light emitted from the layer is concentrated toward the outer side of the light-emitting diode crystal grain to enhance the lateral light emission of the light-emitting diode crystal grain, and at the same time weaken the positive light output of the light-emitting diode crystal grain, thereby making the light-emitting diode of the present invention The output of the polar body grains is uniform.

Referring to FIG. 1 , a light emitting diode die 100 according to an embodiment of the invention includes a substrate 10 , a first semiconductor layer 20 formed on the substrate 10 , and a light emitting layer 30 formed on the first semiconductor layer 20 . a second semiconductor layer 40 on the light-emitting layer 30, a first electrode 50 disposed on the first semiconductor layer 20, and a second electrode 60 disposed on the second semiconductor layer 40. The first semiconductor layer 20 and the second semiconductor layer 40 are used to provide flowing electrons/holes, so that electrons and holes can be combined in the light-emitting layer 30 between the first semiconductor layer 20 and the second semiconductor layer 40. The photons are radiated to the surroundings.

The substrate 10 may be made of sapphire, tantalum carbide (SiC), germanium (Si), gallium nitride (GaN) or the like. In the present embodiment, sapphire is preferred to control the manufacturing cost of the light-emitting chip.

In this embodiment, the first semiconductor layer 20 is preferably an N-type gallium nitride layer, the light-emitting layer 30 is preferably a multi-quantum well gallium nitride layer, and the second semiconductor layer 40 is preferably a P-type nitrogen. Gallium layer.

An upper portion of the first semiconductor layer 20 is recessed downward to form a receiving portion 22. The light-emitting layer 30 is formed on the top surface of the first semiconductor layer 20 other than the accommodating portion 22. The second semiconductor layer 40 is formed on the top surface of the light emitting layer 30. The luminescent layer 30 and the second semiconductor layer 40 are both annular and disposed around the accommodating portion 22 .

The first electrode 50 is made of a metal material having a high reflectance such as silver, aluminum, chromium, or the like. The first electrode 50 is disposed in the receiving portion 22 of the first semiconductor layer 20 . In the embodiment, the first electrode 50 is located at the center of the accommodating portion 22 . The top of the first electrode 50 is higher than the second semiconductor layer 40. It can be understood that the side wall surface of the first electrode 50 facing the light emitting layer 30 may be a slope to obtain a desired reflection effect. The second electrode 60 is disposed on the top surface of the second semiconductor layer 40. The second electrode is annular and disposed around the receiving portion 22. In this embodiment, the second electrode 60 is a transparent conductive layer formed on the top surface of the second semiconductor layer 40, and may be made of indium tin oxide (ITO), nickel gold alloy (Ni/Au) or the like. Indium tin oxide is used to reduce the hindrance to light.

As shown in FIG. 1, the light-emitting diode die 100 of the present invention, in use, is partially projected onto the first electrode 50 by a portion of the light emitted from the light-emitting layer 30 toward the middle of the light-emitting diode die 100. The first electrode 50 The light is made of a metal material having a high reflectivity, and the light is reflected by the first electrode 50 to be emitted toward the outer side of the light emitting diode die 100. Thus, the light emitting layer 30 is emitted toward the light emitting layer 30 by the first electrode 50. The light reflection is concentrated on the outer side of the light-emitting diode die 100 to enhance the lateral light emission of the light-emitting diode die 100 while weakening the positive light output of the light-emitting diode die 100, thereby making the light-emitting diode of the present invention The light output of the bulk crystal grains 100 is uniform.

Hereinafter, a method of manufacturing the light-emitting diode die 100 according to an embodiment of the present invention will be described in detail. The manufacturing method of the LED die 100 includes the following steps:

Step one, providing a substrate 10;

Step 2, a first semiconductor layer 20 is grown on the substrate 10;

Step three, the first semiconductor layer 20 is recessed from the top surface to form a receiving portion 22;

Step 4, sequentially forming the light-emitting layer 30 and the second semiconductor layer 40 on the region of the first semiconductor layer 20 surrounding the accommodating portion 22;

Step 5, the first electrode 50 is electrically connected to the first semiconductor layer 20 in the accommodating portion 22, wherein the top of the first electrode 50 is at least higher than the surface of the luminescent layer 30 away from the substrate 10;

In step six, the second electrode 60 is electrically connected to the second semiconductor layer 40 on the second semiconductor layer 40.

Specifically, the substrate 10 may be made of sapphire, tantalum carbide (SiC), germanium (Si), gallium nitride (GaN) or the like, and is preferably sapphire in this embodiment to control the manufacturing cost of the light-emitting chip. .

In this embodiment, the first semiconductor layer 20 is preferably an N-type gallium nitride layer, the light-emitting layer 30 is preferably a multi-quantum well gallium nitride layer, and the second semiconductor layer 40 is preferably a P-type nitrogen. Gallium layer. The first semiconductor layer 20, the light-emitting layer 30, and the second semiconductor layer 40 may each be subjected to Metal-Organic Chemical Vapor Deposition (MOCVD), Molecular Beam Epitaxy (MBE), or It is formed by a method such as Hydride Vapor Phase Epitaxy (HVPE).

The accommodating portion 22 is formed in an intermediate portion of the first semiconductor layer 20 by etching. The luminescent layer 30 and the second semiconductor layer 40 are both annular and disposed around the accommodating portion 22 .

The first electrode 50 is made of a metal material having a high reflectance such as silver, aluminum, chromium, or the like. The first electrode 50 is disposed in the receiving portion 22 of the first semiconductor layer 20 . In the embodiment, the first electrode 50 is located at the center of the accommodating portion 22 . The top of the first electrode 50 is higher than the top surface of the second semiconductor layer 40. The second electrode 60 is disposed on the top surface of the second semiconductor layer 40. The second electrode is annular and disposed around the receiving portion 22. In this embodiment, the second electrode 60 is a transparent conductive layer formed on the top surface of the second semiconductor layer 40, and may be made of indium tin oxide (ITO), nickel gold alloy (Ni/Au) or the like. Indium tin oxide is used to reduce the hindrance to light.

Referring to FIG. 2 , a backlight module 200 according to an embodiment of the present invention includes a pedestal 70 , a plurality of LED modules 80 disposed on the pedestal 70 , and a light guide plate 90 disposed above the LED module 80 . . The LED module 80 includes a substrate 81, a first electrical connection portion 82 and a second electrical connection portion 83 disposed on a surface of the substrate 81, and is disposed on the substrate 81 and coupled to the first electrical connection portion 82 and the first The two-electrode connecting portion 83 is electrically connected to the light-emitting diode die 100 and the package 84 corresponding to the light-emitting diode die 100 is disposed. The light-emitting diode die 100 is the light-emitting diode die 100 in the above embodiment, and therefore will not be described again. In this embodiment, the first electrode 50 of the LED die 100 is electrically connected to the first electrical connection portion 82 by a wire (not shown), and the second electrode 60 is connected by another wire (not labeled). The second electrical connection portion 83 is electrically connected. The light guide plate 90 includes a light incident surface (not shown) and a light exit surface (not shown). The light incident surface is disposed toward the light emitting diode die 100 of the LED module 80. The light entrance surface may be opposite to the light exit surface or may be adjacent to the light exit surface. When the light incident surface is opposite to the light emitting surface, the backlight module 200 can be formed as a direct type backlight module; when the light incident surface is adjacent to the light emitting surface, the backlight module 200 can be configured as an edge light type backlight module.

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.

100‧‧‧Lighting diode crystal grains

10‧‧‧Substrate

20‧‧‧First semiconductor layer

22‧‧‧ 容部

30‧‧‧Lighting layer

40‧‧‧Second semiconductor layer

50‧‧‧First electrode

60‧‧‧second electrode

200‧‧‧Backlight module

70‧‧‧Base

80‧‧‧Lighting diode module

81‧‧‧Base

82‧‧‧First electrical connection

83‧‧‧Second electrical connection

84‧‧‧Package

90‧‧‧Light guide plate

1 is a schematic cross-sectional view of a crystal of a light-emitting diode of the present invention.

2 is a schematic cross-sectional view of a backlight module of the present invention.

100‧‧‧Lighting diode crystal grains

10‧‧‧Substrate

20‧‧‧First semiconductor layer

22‧‧‧ 容部

30‧‧‧Lighting layer

40‧‧‧Second semiconductor layer

50‧‧‧First electrode

60‧‧‧second electrode

Claims (10)

A light-emitting diode die includes a substrate, a first semiconductor layer formed on the substrate, a light-emitting layer formed on the first semiconductor layer, a second semiconductor layer formed on the light-emitting layer, and disposed on the first semiconductor layer The first electrode and the second electrode disposed on the second semiconductor layer are improved in that the surface of the first semiconductor layer away from the substrate includes a first region and a second region surrounding the first region, the light emitting layer, The second semiconductor layer and the second electrode are sequentially formed on the second region, the first electrode is formed on the first region, and the top of the first electrode is higher than the surface of the light emitting layer away from the substrate, so that the light emitting layer faces The light emitted by the first electrode is reflected by the first electrode and is emitted toward the outer side of the light-emitting diode die. The illuminating diode dies according to claim 1, wherein the first region is recessed downward from a central portion of the first semiconductor layer away from the substrate. The illuminating diode dies of claim 1, wherein the top of the first electrode is higher than the surface of the second semiconductor layer away from the substrate. The illuminating diode dies of claim 1, wherein the first electrode is made of silver, aluminum or chrome. The illuminating diode dies of claim 1, wherein the second electrode is a transparent conductive layer formed on a surface of the second semiconductor layer away from the substrate. A method for fabricating a light-emitting diode die includes the following steps:
Providing a substrate;
Forming a first semiconductor layer on the substrate;
Forming a first region and a second region surrounding the first region on a surface of the first semiconductor layer away from the substrate;
Forming a light emitting layer and a second semiconductor layer on the second region of the first semiconductor;
a first electrode is disposed on the first region of the first semiconductor layer and electrically connected to the first semiconductor layer, wherein a top of the first electrode is higher than a surface of the light emitting layer away from the substrate;
A second electrode is disposed on the second semiconductor layer. The method for fabricating a light-emitting diode according to claim 6, wherein the first region is formed by recessing the first semiconductor layer away from the central portion of the surface of the substrate. The method for fabricating a light-emitting diode according to claim 7, wherein the first region is formed by etching. The method for fabricating a light-emitting diode according to claim 6, wherein the first electrode is made of silver, aluminum or chromium. A backlight module includes a base, a plurality of light emitting diode modules disposed on the base, and a light guide plate disposed above the light emitting diode module, wherein the light emitting diode module includes a patent application The luminescent diode crystal grain according to any one of the items 1 to 5.