JP4084787B2 - Gallium nitride light emitting diode - Google Patents

Description

The present invention relates to a gallium nitride-based light emitting diode, and in particular, achieves an object of mutual matching between a lattice constant and a gallium nitride (GaN) material by using an aluminum indium nitride (Al _x In _1-x N) material of a p-type cladding layer. The present invention relates to a gallium nitride-based light-emitting diode that prevents the characteristics of crystal defects.

  The well-known indium gallium nitride (InGaN) / gallium nitride (GaN) multiple quantum well light emitting diode (MQW LEDs) structure has a p-type aluminum gallium nitride (AlGaN) cladding layer and an indium gallium nitride (InGaN) active light emitting layer. Is covered and protected. However, observing the actual operation reveals that there are many drawbacks. For example, the most stringent two terms are as follows. First, the difference between the lattice constant and the distance between the indium gallium nitride / gallium nitride multiple quantum well light emitting diode structure is very large, and it is easy to form an excessive mechanical stress due to the piezoelectric field effect (piezo-electric field effect). It affects the light emission characteristics of the epitaxial crystal itself, and even destroys the epitaxial crystal itself. Next, if the clad layer aluminum gallium nitride (AlGaN) is not grown at 1000 degrees Celsius or higher, good epitaxial characteristics cannot be obtained, and indium gallium nitride (InGaN) / gallium nitride (GaN) multiple quantum well growth of the active light emitting layer The temperature is about 700 to 850 degrees Celsius. Therefore, when the active light emitting layer is heated to 1000 degrees Celsius or more, its own low-temperature grown multiple quantum well structure is easily destroyed. The light emission efficiency of the (LEDs) structure is affected.

  In view of the above problems, the present invention uses a lattice constant mutual matching technique to manufacture a gallium nitride based light emitting diode, which is much advanced compared to the shortcomings of gallium nitride based light emitting diodes manufactured by conventional techniques. A function shall be achieved.

FIG. 1 is a lattice matching line display diagram in which a III-nitride material is applied to a light emitting diode. The group III nitride has a wide energy gap characteristic (Eg _(AIN) = 6.3 eV; Eg _{( GaN)} = 3.4 eV; Eg _(InN) = 0.7 eV), and the wavelength cover range is from ultraviolet light to red. It is light, and the lattice constant a ₀ of gallium nitride (GaN) is 3.18Å, and the technical idea of the present invention can be seen from FIG.

An object of the present invention is to employ an aluminum indium nitride (Al _x In _1-x N) material, achieve the purpose of mutual matching of the lattice constant and the gallium nitride (GaN) material, and due to excessive stress generated during epitaxial growth. An object of the present invention is to prevent the characteristic of the formed epitaxial defect. Furthermore, from FIG. 1, another object of the present invention is clearly shown. That is, the energy gap of aluminum indium nitride (Al _x In _1-x N) material is larger than that of gallium nitride (GaN) material, and if the p-type cladding layer is used, it is possible to prevent electron overflow. Increasing the probability of coupling in the layer, providing good electrical characteristics, and using aluminum indium nitride (Al _x In _1-x N) as a p-type coating layer, effectively making it a photon due to its wide energy gap characteristics On the other hand, it is to form a limit to finally increase the luminous efficiency. A third object of the present invention is to utilize the fact that the growth temperature of the aluminum indium nitride (Al _x In _1-x N) cladding layer is lower than the growth temperature of p-type aluminum gallium nitride (AlGaN) of the well-known technology, It is to protect the indium gallium (InGaN) active light emitting layer and to increase the luminous efficiency of the device.

The invention of claim 1 is a gallium nitride based light emitting diode,
A substrate made of aluminum oxide single crystal (sapphire);
A buffer layer located on the substrate and made of aluminum gallium indium nitride (Al _1-xy Ga _x In _y N), of which 0 ≦ X <1 and 0 ≦ Y <1;
An n-type gallium nitride (GaN) layer located on the buffer layer;
An active light emitting layer located on the n-type gallium nitride (GaN) layer and made of indium gallium nitride (InGaN);
Located on top of the active luminescent layer, and a p-type cladding layer material is Ru is magnesium doped (Mg-doped) aluminum nitride in Ji arm,
A contact layer located on the p-type cladding layer and made of magnesium-doped (Mg-doped) p-type gallium nitride (GaN);
A gallium nitride-based light-emitting diode characterized by comprising:
A second aspect of the present invention is the gallium nitride-based light emitting diode according to the first aspect, wherein the p-type cladding layer has a thickness of 50 to 3000 mm.
According to a third aspect of the present invention, there is provided the gallium nitride based light-emitting diode according to the first aspect, wherein the growth temperature of the p-type cladding layer is between 600 and 1200 degrees Celsius. Yes.
According to a fourth aspect of the present invention, in the gallium nitride based light-emitting diode according to the first aspect, the gallium nitride based light-emitting diode further comprises an electrode layer positioned on the contact layer or the n-type gallium nitride (GaN) layer. It is a light emitting diode.
The invention of claim 5 is a gallium nitride based light emitting diode,
A substrate made of aluminum oxide single crystal (sapphire);
A buffer layer located on the substrate and made of aluminum gallium indium nitride (Al _1-xy Ga _x In _y N), of which 0 ≦ X <1 and 0 ≦ Y <1;
An n-type gallium nitride (GaN) layer located on the buffer layer;
An active light emitting layer located on the n-type gallium nitride (GaN) layer and made of indium gallium nitride (InGaN);
A p-type cladding layer located on the active light-emitting layer and made of AlInGaN doped with Mg ;
A contact layer located on the p-type cladding layer and made of magnesium-doped (Mg-doped) p-type gallium nitride (GaN);
A gallium nitride-based light-emitting diode characterized by comprising:
A sixth aspect of the present invention is the gallium nitride-based light emitting diode according to the fifth aspect, wherein the p-type cladding layer has a thickness of 50 to 3000 mm.
A seventh aspect of the present invention is the gallium nitride based light-emitting diode according to the fifth aspect, wherein the growth temperature of the p-type cladding layer is between 600 and 1200 degrees Celsius. Yes.
The invention according to claim 8 is the gallium nitride based light emitting diode according to claim 5, further comprising an electrode layer located on the contact layer or the n-type gallium nitride (GaN) layer. It is a light emitting diode.
The invention of claim 9 is a gallium nitride based light emitting diode,
A substrate made of aluminum oxide single crystal (sapphire);
A buffer layer located on the substrate and made of aluminum gallium indium nitride (Al _1-xy Ga _x In _y N), of which 0 ≦ X <1 and 0 ≦ Y <1;
An n-type gallium nitride (GaN) layer located on the buffer layer;
An active light emitting layer located on the n-type gallium nitride (GaN) layer and made of indium gallium nitride (InGaN);
A first cladding layer, which is a double cladding layer positioned on the active light emitting layer, and is made of AlInGaN doped with Mg and positioned on the active light emitting layer. When located on the first cladding layer, and the double-clad layer comprising a second cladding layer, which is the material is magnesium (Mg) doped with aluminum nitride in Ji arm,
A contact layer located on the double clad layer and made of magnesium-doped (Mg-doped) p-type gallium nitride (GaN);
A gallium nitride-based light-emitting diode characterized by comprising:
According to a tenth aspect of the present invention, in the gallium nitride based light-emitting diode according to the ninth aspect, the thickness of the first cladding layer is between 50 and 3000 and the growth temperature is between 600 and 1200 degrees Celsius. A gallium nitride-based light emitting diode is provided.
According to an eleventh aspect of the present invention, in the gallium nitride based light-emitting diode according to the ninth aspect, the thickness of the second cladding layer is between 50 and 3000 and the growth temperature is between 600 and 1200 degrees Celsius. A gallium nitride-based light emitting diode is provided.
The invention of claim 12 is the gallium nitride-based light-emitting diode according to claim 9, further comprising an electrode layer positioned on the contact layer or the n-type gallium nitride (GaN) layer. It is a light emitting diode.
The invention of claim 13 is a gallium nitride based light emitting diode,
A substrate made of aluminum oxide single crystal (sapphire);
A buffer layer located on the substrate and made of aluminum gallium indium nitride (Al _1-xy Ga _x In _y N), of which 0 ≦ X <1 and 0 ≦ Y <1;
An n-type gallium nitride (GaN) layer located on the buffer layer;
An active light emitting layer located on the n-type gallium nitride (GaN) layer and made of indium gallium nitride (InGaN);
Double clad layer overlying the active luminescent layer is (double cladding layer), a first cladding layer which is the material is magnesium doped aluminum nitride in Ji arm located on the active light-emitting layer (first cladding layer) And the above double clad layer comprising a second clad layer that is located on the first clad layer and is made of AlInGaN doped with Mg ;
A contact layer located on the double clad layer and made of magnesium-doped p-type gallium nitride ;
A gallium nitride-based light-emitting diode characterized by comprising:
According to a fourteenth aspect of the present invention, in the gallium nitride based light-emitting diode according to the thirteenth aspect, the thickness of the first cladding layer is between 50 and 3000 and the growth temperature is between 600 and 1200 degrees Celsius. A gallium nitride-based light emitting diode is provided.
According to a fifteenth aspect of the present invention, in the gallium nitride based light-emitting diode according to the thirteenth aspect, the thickness of the second cladding layer is between 50 and 3000 and the growth temperature is between 600 and 1200 degrees Celsius. A gallium nitride-based light emitting diode is provided.
The invention according to claim 16 is the gallium nitride based light-emitting diode according to claim 13, further comprising an electrode layer positioned on the contact layer or the n-type gallium nitride (GaN) layer. It is a light emitting diode.

The present invention is an aluminum nitride-in Ji arm and cladding material, to achieve the lattice constant and gallium nitride (GaN) material mutual matching purposes of preventing poor effect on the epitaxial crystal by the generation of stress excessive during the epitaxial growth. And using the aluminum nitride in Ji beam materials to p-type cladding layer, by the energy gap is larger than the gallium nitride (GaN) materials, to prevent electron overflow, thereby binding the emission layer of an electronic electric pairs increase the probability, as well as effectively to form extreme (confinement) to photons, by the growth temperature of the aluminum nitride in Ji Solid Rudd layer is low, to protect indium gallium nitride (InGaN) active emission layer, and finally Increase luminous efficiency.

  FIG. 2 shows a first embodiment of the gallium nitride based light emitting diode of the present invention. It comprises a substrate 11, a buffer layer 12, an n-type gallium nitride (GaN) layer 13, an active light emitting layer 14, a p-type cladding layer 15 and a contact layer 16.

The substrate 11 is made of aluminum oxide single crystal (sapphire). The material of the buffer layer 12 located on the substrate 11 is aluminum gallium indium nitride (Al _{1 -xy} Ga _x In _y N), of which 0 ≦ X <1 and 0 ≦ Y <1. The n-type gallium nitride (GaN) layer 13 is located on the buffer layer 12. The active light-emitting layer 14 located on the n-type gallium nitride (GaN) layer 13 is made of indium gallium nitride (InGaN). P-type cladding layer 15 overlying the active light-emitting layer 14 and is made of magnesium-doped (Mg-doped) aluminum nitride in Ji beam. The thickness of the p-type cladding layer 15 is between 50 and 3000 mm. The growth temperature of the p-type cladding layer 15 is between 600 degrees Celsius and 1200 degrees Celsius.

  The contact layer 16 located on the p-type cladding layer 15 is made of magnesium-doped (Mg-doped) p-type gallium nitride (GaN).

  The first embodiment of the gallium nitride based light emitting diode of the present invention may further include an electrode layer 17 located on the contact layer 16 or the n-type gallium nitride (GaN) layer 13.

  FIG. 3 shows a second embodiment of the gallium nitride based light emitting diode of the present invention. The second embodiment of the gallium nitride based light-emitting diode according to the present invention includes a substrate 21, a buffer layer 22, an n-type gallium nitride (GaN) layer 23, an active light-emitting layer 24, a p-type cladding layer 25, and a contact layer 26. It has.

The substrate 21 is made of aluminum oxide single crystal (sapphire). The buffer layer 22 located on the substrate 21 is made of aluminum gallium indium nitride (Al _{1 -xy} Ga _x In _y N), and 0 ≦ X <1 and 0 ≦ Y <1 among them. The n-type gallium nitride (GaN) layer 23 is located on the buffer layer 22. The active light emitting layer 24 located on the n-type gallium nitride (GaN) layer 23 is made of indium gallium nitride (InGaN). P-type cladding layer 25 located on the active light-emitting layer 24, Ru is the AlInGaNa which the material is doped with Mg. The p-type cladding layer 25 has a thickness of 50 to 3000 mm. The growth temperature of the p-type cladding layer 25 is between 600 degrees Celsius and 1200 degrees Celsius.

  The second embodiment of the gallium nitride based light emitting diode of the present invention can further comprise an electrode layer 27 located on the contact layer 26 or the n-type gallium nitride (GaN) layer 23.

  FIG. 4 shows a third embodiment of the gallium nitride light emitting diode of the present invention. The third embodiment of the gallium nitride based light emitting diode of the present invention includes a substrate 31, a buffer layer 32, an n-type gallium nitride (GaN) layer 33, an active light emitting layer 34, and a double cladding layer 35. And a contact layer 36.

The substrate 31 is made of aluminum oxide single crystal (sapphire). The buffer layer 32 located on the substrate 31 is made of aluminum gallium indium nitride (Al _{1 -xy} Ga _x In _y N), and 0 ≦ X <1 and 0 ≦ Y <1 among them. The n-type gallium nitride (GaN) layer 33 is located on the buffer layer 32. The active light-emitting layer 34 located on the n-type gallium nitride (GaN) layer 33 is made of indium gallium nitride (InGaN). The double clad layer 35 disposed on the active light emitting layer 34 includes a first clad layer 351 and a second clad layer 352. A first cladding layer 351 on the active light emitting layer 34 is made of AlInGaN doped with Mg. The thickness of the first cladding layer 351 is between 50 and 3000 and the growth temperature is between 600 and 1200 degrees Celsius. The second cladding layer on the first cladding layer (first cladding layer) 351 (second cladding layer) 352 , the material is Ru is aluminum nitride in Ji arm of magnesium (Mg) doped. The thickness of the second cladding layer 352 is between 50 and 3000 and the growth temperature is between 600 and 1200 degrees Celsius.

  The contact layer 36 located on the double clad layer 35 is made of magnesium-doped (Mg-doped) p-type gallium nitride (GaN).

  The third embodiment of the gallium nitride based light emitting diode of the present invention may further include an electrode layer 37 positioned on the contact layer 36 or the n-type gallium nitride (GaN) layer 33.

  FIG. 5 shows a fourth embodiment of the gallium nitride based light emitting diode of the present invention. The fourth embodiment of the GaN-based light emitting diode according to the present invention includes a substrate 41, a buffer layer 42, an n-type gallium nitride (GaN) layer 43, an active light emitting layer 44, and a double cladding layer 45. And a contact layer 46.

The substrate 41 is made of aluminum oxide single crystal (sapphire). The material of the buffer layer 42 located on the substrate 41 is aluminum gallium indium nitride (Al _{1 -xy} Ga _x In _y N), of which 0 ≦ X <1 and 0 ≦ Y <1. The n-type gallium nitride (GaN) layer 43 is located on the buffer layer 42. The active light emitting layer 44 located on the n-type gallium nitride (GaN) layer 43 is made of indium gallium nitride (InGaN). The double clad layer 45 located on the active light emitting layer 44 includes a first clad layer 451 and a second clad layer 452. The first cladding layer on the active light-emitting layer 44 (first cladding layer) 451 is Ru is magnesium (Mg) doped aluminum nitride in Ji beam. The thickness of the first cladding layer 451 is between 50 and 3000 and the growth temperature is between 600 and 1200 degrees Celsius. The second cladding layer (second cladding layer) 452 on the first cladding layer 451 is made of AlInGaN doped with Mg. The thickness of the second cladding layer 452 is between 50 and 3000 and the growth temperature is between 600 and 1200 degrees Celsius.

The contact layer 46 located on the double clad layer 45 is made of magnesium-doped aluminum indium nitride (Al _1-x In _x N) p-type gallium nitride (GaN), of which 0 ≦ X <1.

  The fourth embodiment of the gallium nitride based light emitting diode of the present invention may further include an electrode layer 47 located on the contact layer 46 or the n-type gallium nitride (GaN) layer 43.

  The above is a description of the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention. Any modification or alteration in detail that can be made based on the present invention shall fall within the scope of the claims of the present invention. .

FIG. 3 is a lattice matching line display diagram in which a group III nitride material is applied to a light emitting diode. 1 is a first embodiment diagram of a gallium nitride based light-emitting diode according to the present invention. FIG. FIG. 4 is a diagram showing a second embodiment of the gallium nitride light-emitting diode according to the present invention. FIG. 4 is a diagram showing a third embodiment of the gallium nitride based light-emitting diode according to the present invention. It is a 4th Example figure of the gallium nitride type light emitting diode of this invention.

Explanation of symbols

11 substrate 12 buffer layer 13 n-type gallium nitride layer 14 active light-emitting layer 15 p-type cladding layer 16 contact layer 17 electrode layer 21 substrate 22 buffer layer 23 n-type gallium nitride layer 24 active light-emitting layer 25 p-type cladding layer 26 contact layer 27 Electrode layer 31 Substrate 32 Buffer layer 33 n-type gallium nitride layer 34 Active light emitting layer 35 Double clad layer 351 First clad layer 352 Second clad layer 36 Contact layer 37 Electrode layer 41 Substrate 42 Buffer layer 43 n-type gallium nitride layer 44 Active Light emitting layer 45 Double clad layer 451 First clad layer 452 Second clad layer 46 Contact layer 47 Electrode layer

Claims (16)

In gallium nitride based light-emitting diodes,
A substrate made of aluminum oxide single crystal (sapphire);
A buffer layer located on the substrate and made of aluminum gallium indium nitride (Al _1-xy Ga _x In _y N), of which 0 ≦ X <1 and 0 ≦ Y <1;
An n-type gallium nitride (GaN) layer located on the buffer layer;
An active light emitting layer located on the n-type gallium nitride (GaN) layer and made of indium gallium nitride (InGaN);
Located on top of the active luminescent layer, and a p-type cladding layer material is Ru is magnesium doped (Mg-doped) aluminum nitride in Ji arm,
A contact layer located on the p-type cladding layer and made of magnesium-doped (Mg-doped) p-type gallium nitride (GaN);
A gallium nitride-based light-emitting diode comprising:   2. The gallium nitride light emitting diode according to claim 1, wherein the thickness of the p-type cladding layer is between 50 and 3000 mm.   2. The gallium nitride based light emitting diode according to claim 1, wherein the growth temperature of the p-type cladding layer is set between 600 degrees Celsius and 1200 degrees Celsius.   2. The gallium nitride light emitting diode according to claim 1, further comprising an electrode layer positioned on the contact layer or the n-type gallium nitride (GaN) layer. In gallium nitride based light-emitting diodes,
A substrate made of aluminum oxide single crystal (sapphire);
A buffer layer located on the substrate and made of aluminum gallium indium nitride (Al _1-xy Ga _x In _y N), of which 0 ≦ X <1 and 0 ≦ Y <1;
An n-type gallium nitride (GaN) layer located on the buffer layer;
An active light emitting layer located on the n-type gallium nitride (GaN) layer and made of indium gallium nitride (InGaN);
A p-type cladding layer located on the active light-emitting layer and made of AlInGaN doped with Mg ;
A contact layer located on the p-type cladding layer and made of magnesium-doped (Mg-doped) p-type gallium nitride (GaN);
A gallium nitride-based light-emitting diode comprising:   6. The gallium nitride based light-emitting diode according to claim 5, wherein the thickness of the p-type cladding layer is between 50 and 3000 mm.   6. The gallium nitride based light-emitting diode according to claim 5, wherein the growth temperature of the p-type cladding layer is between 600 and 1200 degrees Celsius.   6. The gallium nitride based light emitting diode according to claim 5, further comprising an electrode layer positioned on the contact layer or the n-type gallium nitride (GaN) layer. In gallium nitride based light-emitting diodes,
A substrate made of aluminum oxide single crystal (sapphire);
A buffer layer located on the substrate and made of aluminum gallium indium nitride (Al _1-xy Ga _x In _y N), of which 0 ≦ X <1 and 0 ≦ Y <1;
An n-type gallium nitride (GaN) layer located on the buffer layer;
An active light emitting layer located on the n-type gallium nitride (GaN) layer and made of indium gallium nitride (InGaN);
A first cladding layer, which is a double cladding layer positioned on the active light emitting layer, and is made of AlInGaN doped with Mg and positioned on the active light emitting layer. When located on the first cladding layer, and the double-clad layer comprising a second cladding layer, which is the material is magnesium (Mg) doped with aluminum nitride in Ji arm,
A contact layer located on the double clad layer and made of magnesium-doped (Mg-doped) p-type gallium nitride (GaN);
A gallium nitride-based light-emitting diode comprising:   The gallium nitride based light-emitting diode according to claim 9, wherein the first cladding layer has a thickness of 50 to 3000 and a growth temperature of 600 to 1200 degrees Celsius. Gallium nitride light emitting diode.   The gallium nitride based light-emitting diode according to claim 9, wherein the thickness of the second cladding layer is between 50 and 3000 and the growth temperature is between 600 and 1200 degrees Celsius. Gallium nitride light emitting diode.   10. The gallium nitride light emitting diode according to claim 9, further comprising an electrode layer positioned on the contact layer or the n-type gallium nitride (GaN) layer. In gallium nitride based light-emitting diodes,
A substrate made of aluminum oxide single crystal (sapphire);
A buffer layer located on the substrate and made of aluminum gallium indium nitride (Al _1-xy Ga _x In _y N), of which 0 ≦ X <1 and 0 ≦ Y <1;
An n-type gallium nitride (GaN) layer located on the buffer layer;
An active light emitting layer located on the n-type gallium nitride (GaN) layer and made of indium gallium nitride (InGaN);
Double clad layer overlying the active luminescent layer is (double cladding layer), a first cladding layer which is the material is magnesium doped aluminum nitride in Ji arm located on the active light-emitting layer (first cladding layer) And the above double clad layer comprising a second clad layer that is located on the first clad layer and is made of AlInGaN doped with Mg ;
A contact layer located on the double clad layer and made of magnesium-doped p-type gallium nitride ;
A gallium nitride-based light-emitting diode comprising:   The gallium nitride based light-emitting diode according to claim 13, wherein the thickness of the first cladding layer is between 50 and 3000 and the growth temperature is between 600 and 1200 degrees Celsius. Gallium nitride light emitting diode.   The gallium nitride based light-emitting diode according to claim 13, wherein the thickness of the second cladding layer is between 50 and 3000 and the growth temperature is between 600 and 1200 degrees Celsius. Gallium nitride light emitting diode.   14. The gallium nitride light emitting diode according to claim 13, further comprising an electrode layer positioned on the contact layer or the n-type gallium nitride (GaN) layer.

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