CN105161590B - A nitride-based light-emitting diode - Google Patents

Abstract

The present invention discloses a kind of nitride light emitting diode, including a substrate, it is disposed with over the substrate and non-mixes a layer u GaN, n-type conductive layer n GaN, active area and limiting layer P AlGaN, V-type hole etching layer is provided with the limiting layer P AlGaN, V-type hole nucleating layer is provided with the etching layer of V-type hole, the three-dimensional fast layer in V-type hole is provided with the nucleating layer of V-type hole, cheated in the V-type and the two-dimentional fast layer in V-type hole is provided with three-dimensional fast layer, cheated in the V-type and P-type conduction layer is disposed with two-dimentional fast layer, p-type contact layer and ITO conductive layer.The quantity of active area is injected in present invention increase p type island region domain hole, improves internal quantum efficiency；Reduce V-type to cheat to form leak channel, improve the reliability of light emitting diode, it is possible to increase the internal quantum efficiency of bluish-green optical chip.

Description

A nitride-based light-emitting diode

technical field

The invention relates to the technical field of light-emitting diodes, and in particular provides a nitride-based light-emitting diode.

Background technique

In recent years, the development of nitride-based light-emitting devices such as nitride-based light-emitting diode devices having a nitride-based semiconductor device layer made of a nitride-based semiconductor has been actively developed. In particular, recently, in order to use nitride-based light-emitting diode elements as light sources of lighting fixtures, developments to improve the light output characteristics of the elements and to increase the additional current have been promoted.

However, in the actual application of LEDs, it faces the problems of efficiency-droop and device reliability deterioration caused by increasing current injection.

Contents of the invention

In order to solve the above problems, the present invention provides a nitride-based light-emitting diode.

To achieve the above object, the technical solution adopted in the present invention is:

A nitride-based light-emitting diode, including a substrate, on which an undoped layer u-GaN, an n-type conductive layer n-GaN, an active region and a confinement layer P-AlGaN are sequentially arranged, and the A V-shaped pit etching layer is arranged on the confinement layer P-AlGaN, a V-shaped pit nucleation layer is arranged on the V-shaped pit etching layer, and a V-shaped pit three-dimensional rapid layer is arranged on the V-shaped pit nucleation layer. A V-shaped two-dimensional rapid layer is arranged on the V-shaped three-dimensional fast layer, and a P-type conductive layer, a P-type contact layer and an ITO conductive layer are sequentially arranged on the V-shaped two-dimensional fast layer.

Preferably, the constituent material of the V-shaped pit etching layer includes GaN; the thickness of the V-shaped pit etching layer is 1-2 nm.

Preferably, the constituent material of the V-shaped pit nucleation layer includes GaN, AlGaN, AlGaInN III-V compound; the thickness of the V-shaped pit nucleation layer is 5-10 nm.

Preferably, the constituent material of the V-shaped pit three-dimensional fast layer includes GaN III-V compound; the thickness of the V-shaped pit three-dimensional fast layer is 10-40nm.

Preferably, the constituent material of the V-shaped pit two-dimensional fast layer includes GaN III-V compound; the thickness of the V-shaped pit two-dimensional fast layer is 50-100 nm.

Preferably, both the V-shaped pit nucleation layer and the V-shaped three-dimensional fast layer are composed of non-doped III-V materials; the V-shaped two-dimensional fast layer is composed of P-type doped III-V materials.

Preferably, an n-electrode is also included, and the n-electrode is fabricated on the part of the n-type conductive layer n-GaN exposed by the etching process.

Preferably, an electrode isolation layer is also included, and the electrode isolation layer is made on the n-electrode and the active region, the confinement layer P-AlGaN, the V-type pit etching layer, the V-type pit nucleation layer, and the V-type pit Between the three-dimensional fast layer, the V-shaped pit two-dimensional fast layer, the P-type conductive layer, the P-type contact layer and the ITO conductive layer.

Preferably, a p-electrode is also included, and the p-electrode is fabricated on the ITO conductive layer.

The invention increases the number of holes injected into the active area in the P-type region, improves the internal quantum efficiency, reduces the leakage channel formed by the V-shaped pit, improves the reliability of the light-emitting diode, and effectively improves the internal quantum efficiency of the blue-green light chip.

Description of drawings

The accompanying drawings described here are used to provide a further understanding of the present invention, and constitute a part of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention, and do not constitute improper limitations to the present invention. In the attached picture:

Fig. 1 is a structural representation of the present invention;

Fig. 2 is a schematic diagram of reaction chamber pressure in each step of the present invention;

Fig. 3 is a schematic diagram of reaction chamber temperature in each step of the present invention;

Fig. 4 is the growth rate schematic diagram in each step of the present invention;

Fig. 5 is a schematic diagram of the rotation speed of the large plate in each step of the present invention.

detailed description

In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention clearer and clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

As shown in Figure 1, the present invention provides a nitride-based light-emitting diode, including a substrate; on the substrate, an undoped layer u-GaN, an n-type conductive layer n-GaN, an active region and Confinement layer P-AlGaN, a V-type pit etching layer is arranged on the confinement layer P-AlGaN, a V-type pit nucleation layer is arranged on the V-type pit etching layer, and a V-type pit nucleation layer is arranged on the V-type pit nucleation layer A V-shaped pit three-dimensional fast layer is arranged on the V-shaped pit three-dimensional fast layer, a V-shaped pit two-dimensional fast layer is arranged on the V-shaped pit three-dimensional fast layer, a P-type conductive layer, a P-type conductive layer, and a P Type contact layer and ITO conductive layer.

Please refer to Figures 2-5, when the V-shaped pit etching layer is formed on the confinement layer P-AlGaN, a low reaction chamber pressure (50mbar), a high reaction chamber temperature (900 degrees), and a low growth rate (TMGa flow rate) are used. 4sccm), high plate rotation speed (1000r/s) epitaxy conditions, last for 800s, effectively etch the conical bottom of the V-shaped pit, reduce the sharpness of the bottom of the V-shaped pit, and form a small flat area at the bottom. In GaN growth, the growth rate depends on the transport rate of TMGa. The epitaxial conditions of low growth rate and high reaction chamber temperature can effectively etch the sharp corner position at the bottom of the V-shaped pit on the one hand, and protect the confinement layer P-AlGaN on the plane on the other hand.

Please continue to refer to those shown in Figures 2-5. When the V-shaped pit nucleation layer is set on the V-shaped pit etching layer, a high reaction chamber pressure (700mbar), a medium reaction chamber temperature (800 degrees), and a medium growth rate (TMGa Flow rate 30sccm), low disk rotation speed (100rpm) epitaxy conditions, lasted 150s, formed 3D island-shaped gallium nitride on the small platform at the bottom of the V-shaped pit. Using the above epitaxial conditions, more nucleation can be performed at the etched flat position at the bottom of the V-shaped pit, and there is no nucleation on the slope of the V-shaped pit as much as possible, so as to avoid the subsequent filling of the V-shaped pit. The quality of the upper crystal deteriorates, reducing the number of holes that can effectively enter the active region.

Please continue to refer to Figures 2-5, when setting the V-shaped pit three-dimensional fast layer on the V-shaped pit nucleation layer, use high reaction chamber pressure (700mbar), medium reaction chamber temperature (900 degrees), and medium growth rate (TMGa flow rate 45sccm), low disk rotation speed (100 rpm) epitaxy conditions, lasted for 400s, and formed 3D island-shaped gallium nitride on the small platform at the bottom of the V-shaped pit. The above-mentioned epitaxial conditions can make the nucleation at the bottom of the V-shaped pit grow rapidly, and form an effective barrier layer at the bottom of the V-shaped pit to prevent leakage of electrons and holes.

Please continue to refer to those shown in Figures 2-5. When the V-shaped pit two-dimensional fast layer is formed on the V-shaped pit three-dimensional fast layer, low reaction chamber pressure (150mbar), high reaction chamber temperature (1000 degrees), and high growth rate are used. The epitaxy conditions of speed (TMGa flow rate 80sccm) and high disk rotation speed (1000 rpm) lasted for 50s to quickly pave the island-shaped gallium nitride and fill the V-shaped pit. Through the above epitaxial conditions, the V-shaped pit can be quickly filled, and a better interface is formed on the slope of the V-shaped pit, which is conducive to increasing the number of holes entering the active region for effective recombination.

Preferably, the constituent material of the V-type pit etching layer includes GaN; the thickness of the V-type pit etching layer is 1-2nm; the V-type pit etching layer can protect the confinement layer P-AlGaN, and the confinement layer P-AlGaN After a long time of high-temperature baking, the surface crystal quality will not deteriorate, so the thinner the better, to avoid the bottom of the V-shaped pit from being effectively etched. The constituent materials of the V-shaped pit nucleation layer include GaN, AlGaN, and AlGaInN III-V compounds; the effective etching at the bottom of the V-shaped pit is small, and the thickness of the V-shaped pit nucleation layer is preferably 5-10 nm. The constituent materials of the V-shaped pit three-dimensional fast layer include GaN III-V compound; the thickness of the V-shaped pit three-dimensional fast layer is 10-40nm; Layers will cause the interface of the V-pit slope to deteriorate during the subsequent filling process. The constituent material of the two-dimensional fast layer of the V-type pit includes GaN III-V compound; the thickness of the two-dimensional fast layer of the V-type pit is preferably 50-100nm; since the thickness of the P-type region needs to be thinner, the two-dimensional fast layer of the V-type pit needs to be thinner. The thickness of the layer cannot be too thick. Both the V-shaped pit nucleation layer and the V-shaped pit three-dimensional rapid layer are composed of non-doped III-V materials; both the V-shaped pit nucleation layer and the V-shaped pit three-dimensional fast layer are non-doped and can be effectively deposited on the bottom of the V-shaped pit. Form a barrier layer that blocks the leakage of electrons and holes; the V-shaped pit two-dimensional fast layer is composed of P-type doped three- and five-group materials; the V-shaped pit two-dimensional fast layer is doped, which can provide more access to the active area for further processing The number of holes that are effectively recombined.

Preferably, an n-electrode is also included, and the n-electrode is fabricated on the part of the n-type conductive layer n-GaN exposed by the etching process; an electrode isolation layer is also included, and the electrode isolation layer is fabricated on the n-electrode And the active region, confinement layer P-AlGaN, V-type pit etching layer, V-type pit nucleation layer, V-type pit three-dimensional fast layer, V-type pit two-dimensional fast layer, P-type conductive layer, P-type contact layer and between the ITO conductive layers; a p-electrode is also included, and the p-electrode is made on the ITO conductive layer.

The invention gradually forms a V-shaped pit etching layer, a V-shaped pit nucleation layer, a V-shaped pit three-dimensional fast layer, a V-shaped pit two-dimensional fast layer, and a P-type conductive layer on the confinement layer P-AlGaN, replacing the traditional confinement layer A P-type conductive layer is formed on the P-AlGaN; this structure allows holes to migrate effectively to the active region and avoids ineffective recombination in the leakage channel, thereby improving the internal quantum efficiency and reducing the leakage of the LED.

Specifically, the present invention first adopts the epitaxial conditions of low reaction chamber pressure, high reaction chamber temperature, low growth rate, and high disk rotation speed, which can effectively etch the bottom of the V-shaped pit and reduce the sharpness of the bottom of the V-shaped pit. Form a small platform; then use high reaction chamber pressure, low reaction chamber temperature, medium growth rate, and low disk rotation speed to form 3D island-like gallium nitride on the small platform at the bottom of the V-shaped pit; then use low reaction chamber pressure, high reaction chamber Temperature, high growth rate, high disk rotation speed, pave the island-shaped gallium nitride, and gradually fill the V-shaped pit; effectively form a non-doped region at the bottom of the V-shaped pit, effectively blocking holes and electrons from leaking from the dislocation line Causes non-luminescent recombination of electron holes.

The invention increases the number of holes injected into the active area in the P-type area, improves the internal quantum efficiency, reduces the leakage channel formed by the V-shaped pit, improves the reliability of the light-emitting diode, and can improve the internal quantum efficiency of the blue-green light chip.

The foregoing description shows and describes preferred embodiments of the present invention, and as previously stated, it is to be understood that the present invention is not limited to the form disclosed herein and should not be construed as excluding other embodiments but may be applied to various other embodiments. Combinations, modifications and circumstances, and can be modified within the scope of the inventive concept described herein, by the above teachings or by skill or knowledge in the relevant field. However, changes and changes made by those skilled in the art do not depart from the spirit and scope of the present invention, and should all be within the protection scope of the appended claims of the present invention.

Claims (9)

1. A nitride-based light-emitting diode, comprising a substrate, characterized in that: an undoped layer u-GaN, an n-type conductive layer n-GaN, an active region and a confinement layer P are sequentially arranged on the substrate - AlGaN, a V-shaped pit etching layer is arranged on the confinement layer P-AlGaN, a V-shaped pit nucleation layer is arranged on the V-shaped pit etching layer, and a V-shaped pit nucleation layer is arranged on the V-shaped pit nucleation layer The V-shaped pit three-dimensional fast layer, the V-shaped pit nucleation layer and the V-shaped pit three-dimensional fast layer are composed of non-doped III-V compound materials, and the V-shaped pit three-dimensional fast layer is provided with a V-shaped pit two A two-dimensional fast layer, on which a P-type conductive layer, a P-type contact layer and an ITO conductive layer are sequentially arranged on the V-shaped pit two-dimensional fast layer. 2 . The nitride-based light-emitting diode according to claim 1 , wherein the material of the V-shaped pit etching layer includes GaN; and the thickness of the V-shaped pit etching layer is 1-2 nm. 3 . 3. A nitride-based light-emitting diode according to claim 1, characterized in that: the constituent materials of the V-shaped pit nucleation layer include GaN, AlGaN, AlGaInN III-V compounds; the V-shaped pit nucleation layer The thickness is 5-10nm. 4. A kind of nitride-based light-emitting diode according to claim 1, characterized in that: the constituent material of the V-shaped pit three-dimensional fast layer comprises GaN III-V compound; the thickness of the V-shaped pit three-dimensional fast layer is 10- 40nm. 5. A kind of nitride-based light-emitting diode according to claim 1, characterized in that: the constituent material of the V-shaped pit two-dimensional fast layer comprises GaN III-V compound; the thickness of the V-shaped pit two-dimensional fast layer is 50-100nm. 6 . A nitride-based light-emitting diode according to claim 1 , wherein the two-dimensional fast layer of the V-shaped pit is made of a P-type doped III-V compound material. 7 . 7 . The nitride-based light-emitting diode according to claim 1 , further comprising an n-electrode, the n-electrode is formed on the part of the n-type conductive layer n-GaN exposed by the etching process. 8. A nitride-based light-emitting diode according to claim 7, characterized in that: it further comprises an electrode isolation layer, and the electrode isolation layer is formed on the n-electrode and the active region, the confinement layer P- Between AlGaN, V-type pit etching layer, V-type pit nucleation layer, V-type pit three-dimensional rapid layer, V-type pit two-dimensional fast layer, P-type conductive layer, P-type contact layer and ITO conductive layer. 9 . The nitride-based light-emitting diode according to claim 1 , further comprising a p-electrode, and the p-electrode is fabricated on the ITO conductive layer.