CN114284407A - Light emitting diode and light emitting device - Google Patents
Light emitting diode and light emitting device Download PDFInfo
- Publication number
- CN114284407A CN114284407A CN202111582726.7A CN202111582726A CN114284407A CN 114284407 A CN114284407 A CN 114284407A CN 202111582726 A CN202111582726 A CN 202111582726A CN 114284407 A CN114284407 A CN 114284407A
- Authority
- CN
- China
- Prior art keywords
- electrode
- light emitting
- layer
- emitting diode
- led
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000004065 semiconductor Substances 0.000 claims abstract description 36
- 238000003892 spreading Methods 0.000 claims abstract description 30
- 230000007480 spreading Effects 0.000 claims abstract description 30
- 239000000463 material Substances 0.000 claims abstract description 23
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 claims description 16
- 230000007704 transition Effects 0.000 claims description 11
- 239000011787 zinc oxide Substances 0.000 claims description 7
- JAONJTDQXUSBGG-UHFFFAOYSA-N dialuminum;dizinc;oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[O-2].[O-2].[Al+3].[Al+3].[Zn+2].[Zn+2] JAONJTDQXUSBGG-UHFFFAOYSA-N 0.000 claims description 6
- GYHNNYVSQQEPJS-UHFFFAOYSA-N Gallium Chemical compound [Ga] GYHNNYVSQQEPJS-UHFFFAOYSA-N 0.000 claims description 4
- BEQNOZDXPONEMR-UHFFFAOYSA-N cadmium;oxotin Chemical compound [Cd].[Sn]=O BEQNOZDXPONEMR-UHFFFAOYSA-N 0.000 claims description 4
- 229910052733 gallium Inorganic materials 0.000 claims description 4
- AMGQUBHHOARCQH-UHFFFAOYSA-N indium;oxotin Chemical compound [In].[Sn]=O AMGQUBHHOARCQH-UHFFFAOYSA-N 0.000 claims description 4
- KYKLWYKWCAYAJY-UHFFFAOYSA-N oxotin;zinc Chemical compound [Zn].[Sn]=O KYKLWYKWCAYAJY-UHFFFAOYSA-N 0.000 claims description 4
- XOLBLPGZBRYERU-UHFFFAOYSA-N tin dioxide Chemical compound O=[Sn]=O XOLBLPGZBRYERU-UHFFFAOYSA-N 0.000 claims description 4
- 229910001887 tin oxide Inorganic materials 0.000 claims description 4
- YVTHLONGBIQYBO-UHFFFAOYSA-N zinc indium(3+) oxygen(2-) Chemical compound [O--].[Zn++].[In+3] YVTHLONGBIQYBO-UHFFFAOYSA-N 0.000 claims description 4
- 229910003437 indium oxide Inorganic materials 0.000 claims description 3
- PJXISJQVUVHSOJ-UHFFFAOYSA-N indium(iii) oxide Chemical compound [O-2].[O-2].[O-2].[In+3].[In+3] PJXISJQVUVHSOJ-UHFFFAOYSA-N 0.000 claims description 3
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 claims description 3
- 239000010937 tungsten Substances 0.000 claims description 3
- XXLJGBGJDROPKW-UHFFFAOYSA-N antimony;oxotin Chemical compound [Sb].[Sn]=O XXLJGBGJDROPKW-UHFFFAOYSA-N 0.000 claims description 2
- 229910001930 tungsten oxide Inorganic materials 0.000 claims description 2
- 230000031700 light absorption Effects 0.000 abstract description 2
- 239000000758 substrate Substances 0.000 description 19
- 230000000694 effects Effects 0.000 description 14
- 229910005540 GaP Inorganic materials 0.000 description 12
- HZXMRANICFIONG-UHFFFAOYSA-N gallium phosphide Chemical compound [Ga]#P HZXMRANICFIONG-UHFFFAOYSA-N 0.000 description 12
- 230000008901 benefit Effects 0.000 description 10
- 238000000034 method Methods 0.000 description 9
- 230000008569 process Effects 0.000 description 9
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 7
- 238000005253 cladding Methods 0.000 description 5
- 239000004020 conductor Substances 0.000 description 5
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 description 5
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 4
- 239000011521 glass Substances 0.000 description 4
- 229910010272 inorganic material Inorganic materials 0.000 description 4
- 239000011147 inorganic material Substances 0.000 description 4
- 238000004519 manufacturing process Methods 0.000 description 4
- SKRWFPLZQAAQSU-UHFFFAOYSA-N stibanylidynetin;hydrate Chemical compound O.[Sn].[Sb] SKRWFPLZQAAQSU-UHFFFAOYSA-N 0.000 description 4
- JBRZTFJDHDCESZ-UHFFFAOYSA-N AsGa Chemical compound [As]#[Ga] JBRZTFJDHDCESZ-UHFFFAOYSA-N 0.000 description 3
- 229910001218 Gallium arsenide Inorganic materials 0.000 description 3
- 229910052581 Si3N4 Inorganic materials 0.000 description 3
- -1 Su8 Substances 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 3
- 229910052594 sapphire Inorganic materials 0.000 description 3
- 239000010980 sapphire Substances 0.000 description 3
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 description 3
- 229910052814 silicon oxide Inorganic materials 0.000 description 3
- 229920000089 Cyclic olefin copolymer Polymers 0.000 description 2
- 239000004593 Epoxy Substances 0.000 description 2
- JMASRVWKEDWRBT-UHFFFAOYSA-N Gallium nitride Chemical compound [Ga]#N JMASRVWKEDWRBT-UHFFFAOYSA-N 0.000 description 2
- 239000004642 Polyimide Substances 0.000 description 2
- 230000004888 barrier function Effects 0.000 description 2
- UMIVXZPTRXBADB-UHFFFAOYSA-N benzocyclobutene Chemical compound C1=CC=C2CCC2=C1 UMIVXZPTRXBADB-UHFFFAOYSA-N 0.000 description 2
- 239000000969 carrier Substances 0.000 description 2
- 239000003989 dielectric material Substances 0.000 description 2
- 239000002019 doping agent Substances 0.000 description 2
- 238000000407 epitaxy Methods 0.000 description 2
- 238000005530 etching Methods 0.000 description 2
- 238000000605 extraction Methods 0.000 description 2
- 239000011810 insulating material Substances 0.000 description 2
- 150000002500 ions Chemical class 0.000 description 2
- 239000000395 magnesium oxide Substances 0.000 description 2
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 2
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 description 2
- 239000012811 non-conductive material Substances 0.000 description 2
- BCCOBQSFUDVTJQ-UHFFFAOYSA-N octafluorocyclobutane Chemical compound FC1(F)C(F)(F)C(F)(F)C1(F)F BCCOBQSFUDVTJQ-UHFFFAOYSA-N 0.000 description 2
- 235000019407 octafluorocyclobutane Nutrition 0.000 description 2
- NQBRDZOHGALQCB-UHFFFAOYSA-N oxoindium Chemical compound [O].[In] NQBRDZOHGALQCB-UHFFFAOYSA-N 0.000 description 2
- BPUBBGLMJRNUCC-UHFFFAOYSA-N oxygen(2-);tantalum(5+) Chemical compound [O-2].[O-2].[O-2].[O-2].[O-2].[Ta+5].[Ta+5] BPUBBGLMJRNUCC-UHFFFAOYSA-N 0.000 description 2
- 229920003229 poly(methyl methacrylate) Polymers 0.000 description 2
- 229920000139 polyethylene terephthalate Polymers 0.000 description 2
- 239000005020 polyethylene terephthalate Substances 0.000 description 2
- 229920001721 polyimide Polymers 0.000 description 2
- 239000004926 polymethyl methacrylate Substances 0.000 description 2
- 235000012239 silicon dioxide Nutrition 0.000 description 2
- 229910001936 tantalum oxide Inorganic materials 0.000 description 2
- PIGFYZPCRLYGLF-UHFFFAOYSA-N Aluminum nitride Chemical compound [Al]#N PIGFYZPCRLYGLF-UHFFFAOYSA-N 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 229910002601 GaN Inorganic materials 0.000 description 1
- GPXJNWSHGFTCBW-UHFFFAOYSA-N Indium phosphide Chemical compound [In]#P GPXJNWSHGFTCBW-UHFFFAOYSA-N 0.000 description 1
- 229910010093 LiAlO Inorganic materials 0.000 description 1
- 239000004697 Polyetherimide Substances 0.000 description 1
- 229910004205 SiNX Inorganic materials 0.000 description 1
- 230000005856 abnormality Effects 0.000 description 1
- NIXOWILDQLNWCW-UHFFFAOYSA-N acrylic acid group Chemical group C(C=C)(=O)O NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 1
- 229910002113 barium titanate Inorganic materials 0.000 description 1
- JRPBQTZRNDNNOP-UHFFFAOYSA-N barium titanate Chemical compound [Ba+2].[Ba+2].[O-][Ti]([O-])([O-])[O-] JRPBQTZRNDNNOP-UHFFFAOYSA-N 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 239000012777 electrically insulating material Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 229920002313 fluoropolymer Polymers 0.000 description 1
- 229910052732 germanium Inorganic materials 0.000 description 1
- GNPVGFCGXDBREM-UHFFFAOYSA-N germanium atom Chemical compound [Ge] GNPVGFCGXDBREM-UHFFFAOYSA-N 0.000 description 1
- YQNQTEBHHUSESQ-UHFFFAOYSA-N lithium aluminate Chemical compound [Li+].[O-][Al]=O YQNQTEBHHUSESQ-UHFFFAOYSA-N 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- ORUIBWPALBXDOA-UHFFFAOYSA-L magnesium fluoride Chemical compound [F-].[F-].[Mg+2] ORUIBWPALBXDOA-UHFFFAOYSA-L 0.000 description 1
- 229910001635 magnesium fluoride Inorganic materials 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229910000484 niobium oxide Inorganic materials 0.000 description 1
- URLJKFSTXLNXLG-UHFFFAOYSA-N niobium(5+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[O-2].[O-2].[Nb+5].[Nb+5] URLJKFSTXLNXLG-UHFFFAOYSA-N 0.000 description 1
- 239000004417 polycarbonate Substances 0.000 description 1
- 229920000515 polycarbonate Polymers 0.000 description 1
- 229920001601 polyetherimide Polymers 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 229920001296 polysiloxane Polymers 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 229910002027 silica gel Inorganic materials 0.000 description 1
- 239000000741 silica gel Substances 0.000 description 1
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- LIVNPJMFVYWSIS-UHFFFAOYSA-N silicon monoxide Chemical compound [Si-]#[O+] LIVNPJMFVYWSIS-UHFFFAOYSA-N 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
- 229910052721 tungsten Inorganic materials 0.000 description 1
- 238000001039 wet etching Methods 0.000 description 1
Images
Landscapes
- Led Devices (AREA)
Abstract
The invention provides a light-emitting diode, which comprises an epitaxial structure, a first electrode and a second electrode, wherein the epitaxial structure is provided with a first surface and a second surface which are opposite, the epitaxial structure sequentially comprises an N-type GaP current spreading layer, an N-type semiconductor layer, a light-emitting layer, a P-type semiconductor layer and an ohmic contact layer from the first surface to the second surface, the first electrode and the second electrode are respectively and electrically connected with the N-type GaP current spreading layer and the ohmic contact layer, and the material of the ohmic contact layer comprises AlxGa(1‑x)As, x is more than 0 and less than or equal to 0.6. By means of the arrangement, the problem of red light absorption of the ohmic contact layer can be improved, and the light emitting efficiency is improved.
Description
Technical Field
The present invention relates to the field of semiconductor manufacturing technologies, and in particular, to a light emitting diode and a light emitting device.
Background
A Light Emitting Diode (LED) is a semiconductor Light Emitting element, generally made of a semiconductor such as GaN, GaAs, GaP, GaAsP, etc., and has a core of a PN junction with a Light Emitting characteristic, electrons are injected from an N region into a P region, holes are injected from the P region into the N region, and a part of minority carriers entering into an opposite region is recombined with majority carriers to emit Light. LEDs have the advantages of high luminous intensity, high efficiency, small size, long service life, etc., and are considered to be one of the most promising light sources currently.
As shown in fig. 1, the conventional light emitting diode 10 includes a substrate 100, a P-type current spreading layer 102, a P-type semiconductor layer 104, a light emitting layer 106, an N-type semiconductor layer 108, an N-type current spreading layer 110, an ohmic contact layer 112 (located only under the electrodes), and an N-electrode 114, which are sequentially stacked from bottom to top. The N-type current spreading layer 110 is AlGaInP. A P electrode 116 is provided on the P-type current spreading layer 102. The conventional light emitting diode 10 has the following problems: 1. in order to ensure good ohmic contact of the N side, GaAs is usually adopted as an ohmic contact layer, and can absorb red light, so that the light emitting efficiency is influenced, the manufacturing process of wet etching is increased, the process is more complicated, and the cost is increased; 2. in order to ensure a good current spreading effect on the N-side, the N-type current spreading layer 110 is grown thicker (the grown AlGaInP layer is thicker and the thickness is greater than 3um), so that after the mesa etching, the height difference between the N-electrode 114 and the P-electrode 116 is larger, which increases the difficulty of the subsequent process.
In addition, as shown in fig. 2, in order to obtain better ESD resistance and current spreading effect, the conventional light emitting diode 10 extends the shape of the N electrode 114, and especially for a small-sized chip (e.g., Mini LED), a finger portion extending from the electrode crosses the middle region of the semiconductor layer, so that there is a risk that the finger will be pushed to the finger, and the risk that the extension will be cracked is increased.
Disclosure of Invention
The invention provides a light emitting diode which comprises an epitaxial structure, a first electrode and a second electrode.
The epitaxial structure has opposing first and second surfaces. The epitaxial structure sequentially comprises an N-type GaP current expansion layer, an N-type semiconductor layer, a light emitting layer, a P-type semiconductor layer and an ohmic contact layer from the first surface to the second surface. The first electrode and the second electrode are respectively electrically connected with the N-type GaP current spreading layer and the ohmic contact layer, wherein the material of the ohmic contact layer comprises AlxGa(1-x)As，0＜x≤0.6。
In one embodiment, the value range of x is more than 0.5 and less than or equal to 0.6.
In one embodiment, the light emitting diode further includes a transparent conductive layer between the ohmic contact layer and the second electrode.
In an embodiment, the thickness of the transparent conductive layer is in a range of 200-5005.
In one embodiment, the material of the transparent conductive layer may include one or more of indium tin oxide, zinc indium oxide, tin oxide, cadmium tin oxide, tin antimony oxide, aluminum zinc oxide, zinc tin oxide, zinc oxide doped gallium, indium oxide doped tungsten, or zinc oxide.
In one embodiment, the epitaxial structure further includes a transition layer between the P-type semiconductor layer and the ohmic contact layer.
In one embodiment, the material of the transition layer comprises AlGaInP.
In one embodiment, the first electrode and the second electrode have a height difference therebetween, and the height difference is less than or equal to 3 μm.
In an embodiment, the light emitting diode further includes an insulating layer covering the substrate, the epitaxial structure, the first electrode, and the second electrode, and having a first opening and a second opening, the first opening being located above the first electrode, and the second opening being located above the second electrode.
In one embodiment, the second electrode includes a starting electrode and an extending electrode, the extending electrode is connected to the starting electrode, and the extending electrode extends from the starting electrode toward the first electrode.
In one embodiment, when looking down from above the light emitting diode toward the epitaxial structure, a first shortest distance is formed between the extension electrode and the first electrode, and the first shortest distance is greater than or equal to 1/2 of the length of the epitaxial structure.
In one embodiment, when looking down from the top of the light emitting diode toward the epitaxial structure, the ratio of the length of the extension electrode to the length of the light emitting diode structure is between 1:20 and 1:3, and the ratio of the width of the extension electrode to the width of the epitaxial structure is between 1:2 and 9: 10.
In one embodiment, the size of the light emitting diode is 300 μm or less.
In one embodiment, the light emitting diode radiates red light.
In an embodiment, the first electrode and the second electrode of the light emitting diode are located on the same side of the epitaxial structure.
The invention also provides a light-emitting device which adopts the light-emitting diode.
An advantage of the present invention is to provide a light emitting diode and a light emitting device using AlxGa(1-x)As materials form an ohmic contact layer, and the phenomenon that the ohmic contact layer absorbs red light to influence the whole light emitting effect is avoided.
Another advantage of the present invention is to provide a light emitting diode and a light emitting device, in which the transparent conductive layer is disposed in cooperation with the ohmic contact layer to achieve a current spreading effect, so as to reduce the height difference of the mesa of the light emitting diode and simplify the process. And, because transparent conducting layer has outstanding current extension effect, the electrode need not to design longer electrode finger and carries out the current extension, that is to say, can reduce electrode size and area, reduce cost reduces electrode shading area, promotes luminance, can avoid the thimble to burst the epitaxy simultaneously.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts; in the following description, the drawings are illustrated in a schematic view, and the drawings are not intended to limit the present invention.
FIG. 1 is a schematic structural diagram of a conventional LED;
FIG. 2 is a schematic top view of a conventional LED;
fig. 3 is a schematic structural diagram of a light emitting diode according to an embodiment of the invention;
fig. 4 is a schematic top view of a light emitting diode according to an embodiment of the invention;
fig. 5-7 are schematic structural views of an epitaxial structure at various stages in the fabrication process.
Reference numerals:
20-a light emitting diode; 22-a substrate; 23-a bonding layer; 24-an epitaxial structure; 241-N type semiconductor layer; 242-a light-emitting layer; 243-P type semiconductor layer; 244 — a first surface; 245-a second surface; 25-a transition layer; 26-N type GaP current spreading layer; 28-ohmic contact layer; 30-a transparent conductive layer; 32-an insulating layer; 321-a first opening; 322-a second opening; 34-a first electrode; 36-a second electrode; h1 — thickness of transparent conductive layer; h2-height difference; l1 — length of light emitting diode; l2 — length of extension electrode; w1 — width of light emitting diode; w2 — width of extended electrode; s-first shortest distance.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some embodiments of the present invention, but not all embodiments; the technical features designed in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other; all other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In the description of the present invention, it is to be understood that the terms "center", "lateral", "up", "down", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations and positional relationships based on those shown in the drawings, are only for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or component in question must have a particular orientation or be constructed and operated in a particular orientation, and therefore, should not be taken as limiting the present invention. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless otherwise specified. In addition, the term "comprises" and any variations thereof mean "including at least".
In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integrally formed connection; can be mechanically or electrically connected; the two components can be directly connected or indirectly connected through an intermediate medium, and the two components can be communicated with each other. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
Referring to fig. 3, fig. 3 is a schematic structural diagram of a light emitting diode 20 according to an embodiment of the invention. To achieve at least one of the advantages or other advantages, an embodiment of the present invention provides a light emitting diode 20. The light emitting diode 20 includes an epitaxial structure 24, a first electrode 34, and a second electrode 36.
An epitaxial structure 24 is disposed on the upper surface of the substrate 22 through a bonding layer 23. In the present embodiment, the substrate 22 is a sapphire substrate. Further illustratively, the substrate 22 may be a transparent substrate, the material of which includes an inorganic material or a group III-V semiconductor material. The inorganic material comprises silicon carbide (SiC), germanium (Ge), sapphire (sapphire), and lithium aluminate (LiAlO)2) Zinc oxide (ZnO), glass or quartz. The group iii-v semiconductor material includes indium phosphide (InP), gallium phosphide (GaP), gallium nitride (GaN), and aluminum nitride (AlN) material. The substrate 22 has sufficient strength to mechanically support the epitaxial structure 24 and is transparent to light exiting the epitaxial structure 24. The thickness of the substrate 22 is preferably 50 μm or more. In addition, to facilitate machining of the substrate 22 after bonding to the epitaxial structures 24, a thickness of no more than 300 μm is preferred.
The material of the bonding layer 23 may be an insulating material and/or a conductive material. Insulating materials include, but are not limited to, Polyimide (PI), benzocyclobutene (BCB), Perfluorocyclobutane (PFCB), magnesium oxide (MgO), Su8, Epoxy (Epoxy), acrylic (acryl resin), cyclic olefin polymer (COC), Polymethylmethacrylate (PMMA), polyethylene terephthalate (PET), Polycarbonate (PC), Polyetherimide (polyethylimide), fluorocarbon polymer (fluorocabon polymer), Glass (Glass), aluminum oxide (Al)2O3) Silicon oxide (SiO)x) Titanium oxide (TiO)2) Tantalum oxide (Ta)2O5) Silicon nitride (SiN)x) Or spin-on glass (SOG). The conductive material includes, but is not limited to, Indium Tin Oxide (ITO), indium oxide (InO), tin oxide (SnO), Cadmium Tin Oxide (CTO), Antimony Tin Oxide (ATO), Aluminum Zinc Oxide (AZO), Zinc Tin Oxide (ZTO), zinc oxide (ZnO), Indium Zinc Oxide (IZO), diamond-like carbon thin film (DLC), Gallium Zinc Oxide (GZO), or the like。
In some embodiments, the second surface 244 of the epitaxial structure 24 close to the substrate 22 may be a roughened surface, so that when the light emitted from the light emitting layer 242 passes through the bonding layer 23 and the second surface 244, the occurrence of total reflection can be reduced, and the light emitting performance of the light emitting diode 20 can be improved.
The epitaxial structure 24 has a first surface 244 and a second surface 245 opposite to each other, and sequentially comprises an N-type GaP current spreading layer 26, an N-type semiconductor layer 241, a light emitting layer 242, a P-type semiconductor layer 243 and an ohmic contact layer 28 from the first surface 244 to the second surface 245.
The N-type GaP current spreading layer 26 is disposed on the substrate 22 for current spreading to improve light extraction effect. An N-type semiconductor layer 241 is disposed on the N-type GaP current spreading layer 26, which may include an N-type cladding layer and an N-type confinement layer from bottom to top. The material of the N-type confinement layer may comprise AlGaInP at a thickness of 500-1000A (angstroms) for confining dopant ions in the N-type cladding layer into the light emitting region. The material of the N-type cap layer may include Si-doped AlINP with a thickness of 2000-6000A for providing electrons.
The light emitting layer 242 is disposed on the N-type semiconductor layer 241 and may be a Quantum Well (QW) structure. In some embodiments, the light emitting layer 242 may also be a Multiple Quantum Well structure (MQW), wherein the Multiple Quantum Well structure includes a plurality of Quantum Well layers (Well) and a plurality of Quantum Barrier layers (Barrier) alternately arranged in a repeating manner. The composition and thickness of the well layer in the light-emitting layer 242 determine the wavelength of light to be generated. In the present embodiment, the light emitted from the light emitting layer 242 is red light, and the material of the light emitting layer 242 includes AlGaInP. That is, the light emitting diode 20 radiates red light, and the light emitting diode 20 is a red light emitting diode.
The P-type semiconductor layer 243 is disposed on the light emitting layer 242, and may include a P-type confinement layer and a P-type cladding layer from bottom to top. The material of the P-type cladding layer may include Mg-doped AlINP with a thickness of 4000-6000A for providing holes. The material of the P-type confinement layer may comprise AlGaInP with a thickness of 500-1000A, which is used to confine the dopant ions in the P-type cladding layer into the light emitting region.
An ohmic contact layer 28 is disposed on the P-type semiconductor layer 243, and a material of the ohmic contact layer 28 includes AlxGa(1-x)As, x is more than 0 and less than or equal to 0.6. By means of AlxGa(1-x)As has almost no light absorption characteristic to AlGaInP red light diode, so As to improve the light emitting effect and light extraction efficiency of the LED 20. Preferably, to prevent the ohmic contact layer 28 from absorbing red light, the forbidden bandwidth of the ohmic contact layer 28 needs to be increased, i.e. the peak wavelength corresponding to the ohmic contact layer 28 is decreased, and considering that too high Al content may cause the subsequent transparent conductive layer 30 to affect the ohmic contact layer 28 during the etching process, x is preferably between 0.5 and 0.6, i.e. 0.5 < x ≦ 0.6.
A first electrode 34 is positioned on the N-GaP current spreading layer 26 and a second electrode 36 is positioned on the ohmic contact layer 28. The first electrode 34 and the second electrode 36 are electrically connected to the N-type GaP current spreading layer 26 and the ohmic contact layer 28, respectively. A height difference H2 is formed between the first electrode 34 and the second electrode 36, and the height difference H2 is less than or equal to 3 μm, so as to reduce the difficulty of the process. Specifically, the light emitting diode 20 further includes a transparent conductive layer 30. The transparent conductive layer 30 is located between the ohmic contact layer 28 and the second electrode 36, and is used for spreading current, so that the current distribution is more uniform, and the light emitting performance of the light emitting diode 20 is improved. By using the transparent conductive layer 30 and the ohmic contact layer 28, compared to the conventional led, the N-type current spreading layer 110 does not need to be formed thickly, so as to reduce the step difference of the mesa and simplify the process. Preferably, the thickness H1 of the transparent conductive layer 30 is in the range of 200-5005.
The transparent conductive layer 30 may be made of a transparent conductive material, and the reliability of the light emitting diode 20 chip may be improved by using the transparent conductive layer 30 of a conductive oxide. As an example, the transparent conductive material may include one or more of Indium Tin Oxide (ITO), Indium Zinc Oxide (IZO), indium oxide (InO), tin oxide (SnO), Cadmium Tin Oxide (CTO), Antimony Tin Oxide (ATO), Aluminum Zinc Oxide (AZO), Zinc Tin Oxide (ZTO), gallium doped zinc oxide (GZO), tungsten doped indium oxide (IWO), or zinc oxide (IWO), but the disclosure is not limited thereto.
In one embodiment, as shown in fig. 3, the epitaxial structure 24 further includes a transition layer 25. The light emitting diode 20 further comprises an insulating layer 32.
The transition layer 25 is positioned between the P-type semiconductor layer 243 and the ohmic contact layer 28. The material of the transition layer 25 includes AlGaInP to function as a transition layer to reduce generation of defects due to lattice mismatch between the P-type semiconductor layer 243 and the ohmic contact layer 28. The thickness of the transition layer 25 ranges from 0.1 to 0.6 μm.
The insulating layer 32 covers the substrate 22, the epitaxial structure 24, the first electrode 34, and the second electrode 36, and has a first opening 321 and a second opening 322. The first opening 321 is located above the first electrode 34, and the second opening 322 is located above the second electrode 36, so as to facilitate subsequent use of the light emitting diode 20. The insulating layer 32 has different effects according to the positions involved, for example, the sidewall covering the epitaxial structure 24 can prevent the conductive material from leaking to electrically connect the N-type semiconductor layer 241 and the P-type semiconductor layer 243, thereby reducing the short circuit abnormality of the light emitting diode 20, but the embodiment of the disclosure is not limited thereto. The material of the insulating layer 32 includes a non-conductive material. The non-conductive material is preferably an inorganic material or a dielectric material. The inorganic material may comprise silica gel (Silicone). The dielectric material including aluminum oxide (AlO), silicon nitride (SiNx), silicon oxide (SiOx), titanium oxide (TiOx), or magnesium fluoride (MgFx) may be an electrically insulating material. For example, the insulating layer 32 may be silicon dioxide, silicon nitride, titanium oxide, tantalum oxide, niobium oxide, barium titanate, or a combination thereof, which may be, for example, a bragg reflector (DBR) formed by repeatedly stacking two materials.
In one embodiment, as shown in FIG. 4, the second electrode 36 includes a start electrode 362 and an extension electrode 364. The extension electrode 364 is connected to the start electrode 362, and the extension electrode 364 extends from the start electrode 362 toward the first electrode 34. The current spreading effect can be further enhanced by the arrangement of the extension electrode 364.
When the light emitting diode 20 is viewed from above toward the epitaxial structure 24, that is, as shown in fig. 4, the extension electrode 364 and the first electrode 34 have a first shortest distance S, and the first shortest distance S is equal to or greater than 1/2 of the length L1 of the light emitting diode 20. In other words, the second electrode 36 and the first electrode 34 are both away from the middle region of the led 20, so as to prevent the thimble from pushing the electrodes, and reduce the risk of breaking the epitaxy. The second electrode 36 is biased to the left end of the light emitting diode 20, and the first electrode 34 is biased to the right end of the light emitting diode 20, compared to the first electrode 34. The ratio of the length L2 of the extension electrode 364 to the length L1 of the light emitting diode 20 is 1:20 to 1:3, and the ratio of the width W2 of the extension electrode 364 to the width W1 of the epitaxial structure 24 is 1:2 to 9: 10. By virtue of the excellent current spreading effect of the transparent conductive layer 30, the second electrode 36 does not need to design a longer electrode finger for current spreading, that is, the size and area of the electrode can be controlled within the above range, the middle region is avoided, the thimble is prevented from being pushed to the electrode, and the risk of epitaxial crack is reduced.
In one embodiment, the light emitting diode 20 may be a small-sized light emitting diode, and specifically, the size of the light emitting diode 20 may be less than 300 μm, that is, the length and width of the light emitting diode 20 are both less than or equal to 300 μm.
Referring to fig. 5-7, fig. 5-7 are schematic structural views of the epitaxial structure 24 at various stages in the fabrication process.
Referring to fig. 5, a buffer layer 52 and an etch stop layer 54 are sequentially grown on an epitaxial growth substrate 50. Buffer layer 52 may be gallium arsenide and etch stop layer 54 is used for subsequent removal of epitaxial growth substrate 50.
Next, referring to fig. 6, the semiconductor light emitting sequence is continued to grow, that is, the ohmic contact layer 28, the transition layer 25, the P-type semiconductor layer 243, the light emitting layer 242, the N-type semiconductor layer 241, and the N-type GaP current spreading layer 26 are sequentially grown on the etch stop layer 54.
Subsequently, referring to fig. 7, a semiconductor light emitting sequence is transferred onto the substrate 22 of the present embodiment through the bonding layer 23 to form an epitaxial structure 24 with the N-type semiconductor layer 241 on the bottom and the P-type semiconductor layer 243 on the top. Specifically, etch stop layer 54 in fig. 6 cuts the semiconductor light emitting sequence off epitaxial growth substrate 50 and connects the semiconductor light emitting sequence to substrate 22 through bonding layer 23. Then, the ohmic contact layer 28 is etched to the N-type GaP current spreading layer 26 to expose the N-type GaP current spreading layer 26, and the first electrode 34 is provided.
The present embodiment further provides a light emitting device, which uses the light emitting diode 20 provided in any of the above embodiments, and details of the structure and technical effects are not repeated.
In summary, an advantage of the present invention is to provide a light emitting diode 20 and a light emitting device, in which an AlxGa (1-x) As material is used to form the ohmic contact layer 28, so As to prevent the ohmic contact layer 28 from absorbing red light and affecting the overall light emitting effect.
Another advantage of the present invention is to provide a light emitting diode 20 and a light emitting device, in which the transparent conductive layer 30 is disposed in cooperation with the ohmic contact layer 28 to achieve a current spreading effect, so as to reduce a step height of the light emitting diode 20 and simplify the process. Moreover, since the transparent conductive layer 30 has an excellent current spreading effect, the electrode does not need to design a longer electrode finger for current spreading, that is, the size and area of the electrode can be reduced, the cost can be reduced, the thimble can be prevented from being pushed to the electrode, and the risk of the electrode being pushed to be cracked can be reduced.
In addition, it will be appreciated by those skilled in the art that, although there may be many problems with the prior art, each embodiment or aspect of the present invention may be improved only in one or several respects, without necessarily simultaneously solving all the technical problems listed in the prior art or in the background. It will be understood by those skilled in the art that nothing in a claim should be taken as a limitation on that claim.
Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.
Claims (16)
1. A light emitting diode, characterized by: the light emitting diode includes:
the epitaxial structure is provided with a first surface and a second surface which are opposite, and the epitaxial structure sequentially comprises an N-type GaP current spreading layer, an N-type semiconductor layer, a light emitting layer, a P-type semiconductor layer and an ohmic contact layer from the first surface to the second surface;
the first electrode is electrically connected with the N-type GaP current expansion layer;
a second electrode electrically connected to the ohmic contact layer;
wherein the material of the ohmic contact layer comprises AlxGa(1-x)As，0＜x≤0.6。
2. The led of claim 1, wherein: the value range of x is more than 0.5 and less than or equal to 0.6.
3. The led of claim 1, wherein: the light emitting diode further comprises a transparent conductive layer located between the ohmic contact layer and the second electrode.
4. The light-emitting diode according to claim 3, wherein: the thickness range of the transparent conductive layer is 200-500.
5. The light-emitting diode according to claim 3, wherein: the material of the transparent conductive layer can include one or more of indium tin oxide, zinc indium oxide, tin oxide, cadmium tin oxide, tin antimony oxide, aluminum zinc oxide, zinc tin oxide, zinc oxide doped with gallium, indium oxide doped with tungsten, or zinc oxide.
6. The led of claim 1, wherein: the epitaxial structure further comprises a transition layer located between the P-type semiconductor layer and the ohmic contact layer.
7. The light-emitting diode of claim 6, wherein: the material of the transition layer includes AlGaInP.
8. The led of claim 1, wherein: the first electrode and the second electrode have a height difference therebetween, and the height difference is less than or equal to 3 μm.
9. The led of claim 1, wherein: the light emitting diode further comprises an insulating layer, wherein the insulating layer covers the epitaxial structure, the first electrode and the second electrode and is provided with a first opening and a second opening, the first opening is located above the first electrode, and the second opening is located above the second electrode.
10. The led of claim 1, wherein: the second electrode includes a starting electrode and an extension electrode, the extension electrode is connected with the starting electrode, and the extension electrode extends from the starting electrode towards the direction of the first electrode.
11. The led of claim 10, wherein: when viewed from above the light emitting diode toward the epitaxial structure, a first shortest distance is provided between the extension electrode and the first electrode, and the first shortest distance is equal to or greater than 1/2 of the length of the light emitting diode.
12. The led of claim 10, wherein: when the light emitting diode is overlooked from the upper part of the light emitting diode to the epitaxial structure, the ratio of the length of the extension electrode to the length of the light emitting diode is 1: 20-1: 3, and the ratio of the width of the extension electrode to the width of the light emitting diode is 1: 2-9: 10.
13. The led of claim 1, wherein: the size of the light emitting diode is less than 300 mu m.
14. The led of claim 1, wherein: the light emitting diode radiates red light.
15. The led of claim 1, wherein: the first electrode and the second electrode are located on the same side of the epitaxial structure.
16. A light emitting device, characterized in that: use of a light emitting diode according to any of claims 1-15.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111582726.7A CN114284407A (en) | 2021-12-22 | 2021-12-22 | Light emitting diode and light emitting device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111582726.7A CN114284407A (en) | 2021-12-22 | 2021-12-22 | Light emitting diode and light emitting device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114284407A true CN114284407A (en) | 2022-04-05 |
Family
ID=80873937
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111582726.7A Pending CN114284407A (en) | 2021-12-22 | 2021-12-22 | Light emitting diode and light emitting device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114284407A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116364827A (en) * | 2023-05-29 | 2023-06-30 | 江西兆驰半导体有限公司 | Mini LED and preparation method thereof |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1331494A (en) * | 2000-06-29 | 2002-01-16 | 中国科学院半导体研究所 | Integrated device of laser and photoelectric switch |
| US20090278160A1 (en) * | 2008-05-09 | 2009-11-12 | Advanced Optoelectronic Technology Inc. | Radiation emitting semiconductor device |
| CN106328787A (en) * | 2016-08-30 | 2017-01-11 | 天津三安光电有限公司 | Light-emitting diode for plant illumination and manufacturing method thereof |
| CN110164989A (en) * | 2019-06-03 | 2019-08-23 | 长春理工大学 | N-type AlxGa1-xAs material system semiconductor surface Ohm contact electrode and preparation method thereof |
| CN110915005A (en) * | 2018-05-02 | 2020-03-24 | 天津三安光电有限公司 | Light emitting diode and manufacturing method thereof |
| CN113224214A (en) * | 2021-03-24 | 2021-08-06 | 华灿光电(苏州）有限公司 | Red light emitting diode epitaxial wafer and preparation method thereof |
| CN113380931A (en) * | 2021-04-22 | 2021-09-10 | 华灿光电(苏州）有限公司 | Red light emitting diode chip capable of improving luminous efficiency and preparation method thereof |
| CN113690354A (en) * | 2021-06-30 | 2021-11-23 | 华灿光电（浙江）有限公司 | GaAs-based light emitting diode chip and manufacturing method thereof |
-
2021
- 2021-12-22 CN CN202111582726.7A patent/CN114284407A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1331494A (en) * | 2000-06-29 | 2002-01-16 | 中国科学院半导体研究所 | Integrated device of laser and photoelectric switch |
| US20090278160A1 (en) * | 2008-05-09 | 2009-11-12 | Advanced Optoelectronic Technology Inc. | Radiation emitting semiconductor device |
| CN106328787A (en) * | 2016-08-30 | 2017-01-11 | 天津三安光电有限公司 | Light-emitting diode for plant illumination and manufacturing method thereof |
| CN110915005A (en) * | 2018-05-02 | 2020-03-24 | 天津三安光电有限公司 | Light emitting diode and manufacturing method thereof |
| CN110164989A (en) * | 2019-06-03 | 2019-08-23 | 长春理工大学 | N-type AlxGa1-xAs material system semiconductor surface Ohm contact electrode and preparation method thereof |
| CN113224214A (en) * | 2021-03-24 | 2021-08-06 | 华灿光电(苏州）有限公司 | Red light emitting diode epitaxial wafer and preparation method thereof |
| CN113380931A (en) * | 2021-04-22 | 2021-09-10 | 华灿光电(苏州）有限公司 | Red light emitting diode chip capable of improving luminous efficiency and preparation method thereof |
| CN113690354A (en) * | 2021-06-30 | 2021-11-23 | 华灿光电（浙江）有限公司 | GaAs-based light emitting diode chip and manufacturing method thereof |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116364827A (en) * | 2023-05-29 | 2023-06-30 | 江西兆驰半导体有限公司 | Mini LED and preparation method thereof |
| CN116364827B (en) * | 2023-05-29 | 2023-08-29 | 江西兆驰半导体有限公司 | Mini LED and preparation method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR102606543B1 (en) | Light-emitting device | |
| US10559717B2 (en) | Light-emitting device and manufacturing method thereof | |
| EP2403022B1 (en) | Manufacturing method of semiconductor light emitting diode | |
| US11942509B2 (en) | Light-emitting device | |
| KR100714638B1 (en) | Facet extraction type led and method for manufacturing the same | |
| TWI720026B (en) | Light-emitting device | |
| KR100867529B1 (en) | Vertical light emitting device | |
| JP2004071644A (en) | Nitride semiconductor light emitting device | |
| KR101111750B1 (en) | Semiconductor Light Emitting Device | |
| CN113851567B (en) | Light emitting diode chip and light emitting device | |
| US20220231196A1 (en) | Semiconductor light-emitting device | |
| TW202029529A (en) | Light-emitting device and manufacturing method thereof | |
| CN109494286B (en) | Semiconductor device with a plurality of semiconductor chips | |
| CN114284407A (en) | Light emitting diode and light emitting device | |
| CN108431970B (en) | Light emitting element | |
| KR20200065872A (en) | Light emitting device | |
| KR20170095675A (en) | Light emitting device | |
| KR100644215B1 (en) | Luminous device and the method therefor | |
| TWI816191B (en) | Light emitting device | |
| US20240290912A1 (en) | Light emitting diode and light emitting device | |
| US20240186455A1 (en) | Vertical-type light-emitting diode and light-emitting device | |
| CN220324473U (en) | Flip-chip light-emitting element and light-emitting device | |
| CN221727143U (en) | Light emitting diode, diode package and light emitting device | |
| US20240347671A1 (en) | Light-emitting diode and light-emitting device | |
| US20220131032A1 (en) | Micro light-emitting device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |