TW200814355A - High brightness light emitting diode - Google Patents

Abstract

The invention provides a high brightness light emitting diode. It includes: a plate substrate; a quantum unit formed by a layer of gallium nitride series semiconductor on the said substratefor producing light by quantum effect; and two electrodes forming ohm contact with the quantum unit for providing electrical power. Each electrode comprises: an insulation layer formed by insulation material which becomes heterojunction energy band with quantum unit; a reflection layer with high reflection coefficient material formed on the insulation layer for compensating the Fresnel loss of reflection layer; and at least one electric conduction layer formed on the reflection layer with electric conduction material to conduct the diffusion current. It can form a Schottky rectified contact. The current can concentrate and pass through the central region to increase the inner quantum effect of the said region. The present invention increases the total brightness of emitting light and reduce the overheat problem of component at the same time.

Description

200814355 IX. Description of the invention: [Technical field to which the invention pertains] The present invention relates to a solid-state light-emitting element, and more particularly to a high-intensity light-emitting diode. [Prior Art] The light-emitting diode has the advantages of long life, low power consumption, small volume, low driving voltage, fast reaction rate, high recognition rate, etc. It is a new-generation light source, and its trace applications can be seen everywhere in daily life. Referring to FIG. 1, in general, the light-emitting diode i includes a rectangular plate-shaped substrate 11 layer. A GaN-based semiconductor material is epitaxially formed on the substrate n, and a layer is formed on the substrate. The top surface of the current diffusion layer 13' and the two electrodes 14 provide electrical energy. The ghost substrate is composed of a material whose lattice constant matches the quantum unit, such as sapphire. The quantum unit 12 has a layer connected to the substrate and includes a central region 124 and a first cladding layer 121 surrounding the outer region 125 of the central region 124, a layer from the first An active layer 123 formed on the top surface of the central portion 124 of the first type of cladding layer 121, and a second type of cladding layer 122 formed on the top surface of the active layer 123, the first type and the second type are covered. The layers 121, 122 form a quantum moon b flat with respect to the active layer 123 to generate light by a photoelectric effect. The central region 124 of the first type cladding layer 121 of the quantum unit 12, the active layer 123 and the second type cladding layer 122, and the current diffusion layer 13 formed on the second type cladding layer 122 constitute a main outward light emitting component. Mesa platform area 100. 5 200814355 The current diffusion layer η is made of a material that can transmit light and has a uniform current dispersion, such as bismuth tin oxide (known in the industry), so that the current level can be uniformly spread laterally when the electrode η is applied with electric energy. After passing through the quantum unit 12, it is circulated and raised to improve luminous efficiency. * The two electrodes 14 are formed in a sheet shape by a metal such as copper or silver and/or an alloy thereof, and are disposed at two diagonal corners of the light-emitting diode 相对 relatively far apart from each other, and are respectively associated with the quantum unit 12 Type-coating layer i2i and cough

The current spreading layer 13 is in contact with each other to supply electrical energy to the quantum unit 12 to cause the quantum unit 12 to generate light. When electric energy is applied from the two electrodes 14, the current diffusion mode is as shown by an imaginary line arrow in the figure, and the circumferential surface of the electrode 14 from which the sheet is in ohmic contact with the current diffusion layer 13 is laterally dispersed horizontally through the current diffusion layer 13. Circulating, and the bottom surface of the electrode 14 in ohmic contact with the current diffusion layer 13 is directly passed downwardly through the current diffusion layer 14 and then diffuses vertically downward through the second type of the cladding layer 122 of the quantum unit 12, the active layer. 123 and the first type of cladding layer 121, and since the impedance of the substrate 11 is relatively greater than the first type of cladding layer 121, the current flows horizontally to the other piece along the bottom of the first type of cladding layer 121 and the first The electrode 14 of the one-type cladding layer 121 in ohmic contact forms a path, so that the quantum unit 12 generates photons by the photoelectric effect, thereby causing the light-emitting diode 1 to emit light. Since the process of current spreading is performed by selecting the channel with the smallest impedance and the shortest path, most of the current will pass directly from the bottom surface of the electrode 14 in ohmic contact with the current diffusion layer 13 through the current diffusion layer 13 ' The vertical downward diffusion flow generates light through the quantum unit 12, and the other portion 6 200814355 knife electric/cucumber θ self-ww: the flow diffusion layer 13 is horizontally dispersed and then circulated; the direct diffusion flow is generated by the quantum unit 12 Light, therefore, the area where the internal quantum effect occurs in the region below the electrode 14 in which the sheet is in ohmic contact with the current diffusion layer 13 is more than the other partial regions (mainly the Mesa platform region 100), and becomes the main light. The area is generated, and at the same time, the light generated by the area is reflected by the sheet electrode 14 back to the inside of the light-pole body 1 and converted into internal heat, which cannot be emitted outward, and also 'Not only the waste current flowing through this area is wasted, but also the problem of overheating. Therefore, if the diffusion path of the LED current can be effectively planned, the current can be relatively concentrated through the region that can directly emit light (M(10) platform area), which can not only increase the luminance of the light-emitting diode i, but also: It can solve the problem of overheating of components. SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a high brightness light emitting diode without element overheating problems. Thus, the high-intensity light-emitting diode of the present invention comprises a plate-shaped substrate, a --layer quantum unit, a first electrode, and a second electrode. The subunit is formed on the substrate by a gallium nitride based semiconductor material and has a layer connected to the substrate and includes a central region of the ghost and a first type of cladding layer surrounding the outer region of the central region. An active layer formed from a top surface of the central portion of the first type of cladding layer, a layer from the top surface of the active layer: a second type of cladding layer formed thereon, and two layers respectively formed on the first type of cladding layer a recessed hole in the outer ring region of the layer and the surface of the second type of cladding layer, the first and second type 7 200814355 batch coating forms a quantum energy barrier with respect to the active layer and LV soil + i

The first electrode of the sheet is disposed in the one of the recessed holes, wherein the first insulating layer is made of an insulating material, and the first insulating layer is made of a material from the top surface of the first insulating layer. The first conductive layer is formed with the top of the layer facing upward and the cladding layer is in ohmic contact. The second electrode of the sheet is disposed in the other recessed hole and is compatible with the sheet

Contacted second conductive layer.

The area underneath the second electrode is such that the current is relatively concentrated through other regions that can directly illuminate outward, and at the same time, a barrier energy band is formed, forming a Schottky rectifying contact (Sch〇uky c〇ntact). In turn, the brightness of the light-emitting body is increased, and at the same time, the problem of overheating of the components is solved. The above and other technical contents, features and effects of the present invention will be apparent from the following detailed description of the preferred embodiments of the invention. Before the present invention is described in detail, it is to be noted that in the following description, similar elements are denoted by the same reference numerals. Referring to FIG. 2, a first preferred embodiment of the high-brightness light-emitting diode 2 of the present invention includes a rectangular substrate 21 and a layer of a gallium nitride-based semiconductor material formed on the substrate. a quantum unit 22 on 21, a current diffusion layer 23 formed on the top surface of the quantum unit 22, a first electrode 3, and a second electric source 4 for cooperating with the first electrode 3 of the sheet for supplying electric energy 〇

The block substrate 21 has a base layer 211 which is made of a material having a high thermal conductivity and which conducts internal heat, and a layer which is formed of a material having a high reflectance on the bottom layer 211 for reflecting light. The S subunit 22 has a layer connected to the surface of the main reflective layer 212 of the substrate 21 and includes a central region 224 and a first type of cladding layer 221 and a layer surrounding the outer region 225 of the central region 224. An active layer 223 formed from a top surface of the central portion 224 of the first type of cladding layer 221, and a second type of cladding layer 222 formed from a top surface of the active layer 223, two of which are respectively formed on the first type The outer annular region 225 of the layer 221 and the concave hole 226 on the surface of the second type cladding layer 222. The first and second type cladding layers 221 and 222 form a quantum energy barrier with respect to the active layer 223 to generate light by a photoelectric effect. The central region of the first-type cladding layer 221 of the quantum unit 22, the active layer milk and the first-type cladding layer 222, and the current diffusion layer 23 formed on the second-type cladding layer 222 constitute a component that mainly emits light outward. The ^ platform area is said. The two (four) holes 226 are disposed at opposite corners of the light-emitting diode 2 at a distance from each other, and the recess 226 formed in the outer ring region 225 of the first-type cladding layer 221 has a depth not exceeding the first a bottom surface of the -type cladding layer 221 connected to the substrate 21, and the recessed hole similarity formed in the second type cladding layer 222 does not exceed the second type of cladding layer 222 and the active layer such as the connection 2 200814355, the current diffusion layer 23 is made of a material that can transmit light and can uniformly disperse current, for example, indium tin oxide (known in the industry as ITO), and the current level can be uniformly and laterally diffused when the electrode 14 is applied with electric energy. And further: vertically diffusing through the quantum unit 12 to enhance internal luminous efficiency. The first electrode 3 of the sheet is disposed in a recess 226 formed in the 225 of the first type cladding layer 221 and has a layer of insulating layer 31 made of an insulating material, and the layer is made of a material having a high reflection coefficient. a first reflective layer 32 formed on the faint edge ==, and a layer formed of a conductive material from the surface of the metal 1^=3? and coated with the first type of cladding layer such as a phase pattern #221 4 electrical layer 33, The first insulating layer 31 and the adjacent first plenum layer 22! The base rectification is caused by the difference of the materials, and the first reflection and the second =1 can be replenished; Such as nitrogen cut oxidation...χ), 4匕铭("A1 η, long v 1A〇2 j '

Ta〇) 2/, emulsified wrong (Zr〇2), zinc oxide (Zn〇), oxidized buckle (h〇5), magnesium fluoride (MgF2), titanium nitride (T-(shot layer 32盥 first tomb)贲麻. ^Hand composition 苐一反钦, steel, copper uranium I 4 is an example · such as gold, Ming, silver, recorded, Pakistan, 鈒 special metal, and / or these metals $ μ yv gold, while paying attention The material of the first reflective layer 32 is formed: the resultant value is greater than the resistance of the material constituting the first guide w 33. The resistance of the material of the layer 33, in addition, the reed together = 3 can be respectively The above metal, and/or alloy forms at least a double 'bumpy structure, and a better conductive effect can be obtained. The layer v electric 4 pieces of the second electrode 4 are disposed on the 10 200814355 concave formed on the second type cladding layer 222 The hole 226 passes through the mine and has a second insulating layer 41 made of an insulating material on the outside surface, and has a high reflection coefficient material from the first layer. The top of the layer 41 faces the upper reflective layer 42, and one layer is made of a conductive material from the Λ' Β ^ir m, ^ a top of the reflective layer 42 faces up and down and the current is diffused with the layer, and the layer 13 is electrically Pifu simultaneously access the second-type layer, an ohmic layer 222 sprite dip dream - Soil push Λ ^ Sin complex of the second insulating layer and the adjacent portion = coating, because of differences in the current spreading layer material can result in a heterogeneous

The step r forms a Schottky rectifying contact, and the second reflecting layer 42 can cause secondary reflection of light to compensate for the loss of Philippine smear; similarly, the insulating material constituting the first I-edge layer 41 is, for example, nitrided. Broken (then, oxidized stone (Sax), titanium oxide (Ti〇2), alumina (9) ^ small oxidized (7) ~), zinc oxide (ZnO), oxidation button (Ta2 〇 5), magnesium fluoride (Μ #〗), nitrogen: 匕Ti (TlN) #, the material constituting the second reflective layer 42 and the second conductive layer 43 is metal such as gold, Ming, silver, money, Chin, 锢, copper, rhyme, money, table, etc. And/or the alloy 5 formed by the metals, it should be noted that the resistance of the material constituting the second reflective layer 42 must be greater than the resistance of the material constituting the second conductive layer 43. In addition, the layer of the second conductive layer 43 At least one layer of the conductive film may be formed by the above-mentioned metal and/or alloy, respectively, to obtain a better conductive effect. When electric energy is applied from the first and second electrodes 3, 4, the current diffusion mode is as indicated by an imaginary line arrow in the figure, since the current is blocked by the first insulating layer 31 of the first electrode 3, and from the first electrode 3 The side surface of the first conductive layer 33 electrically connected to the current diffusion layer 23 is laterally horizontally dispersed through the current diffusion layer 23, and is diffused downward from the current diffusion layer 23 to flow through the quantum unit 22 of the 11th 200814355 type 2 cladding layer 222. The active layer 223 and the first type of cladding layer 221 are further horizontally and horizontally diffused along the bottom of the first type of cladding layer 221, and are further flowed upward due to the second insulating layer 41 of the second electrode 4 being blocked. The peripheral surface of the second conductive layer 43 of the two electrodes 4 enters the second electrode 4 to form a path, and the quantum unit 22 generates photons by internal quantum effects, thereby causing the light-emitting diode 2 to emit light. Since the first and second insulating layers 3i, 4i of the first and second electrodes 3, 4 are blocked, the area under the H and the two electrodes 3, 4 has almost no current diffusion flow, and therefore, the quantum unit 22 corresponds to The portion of this region is a region where photons are hardly generated. Therefore, light generated in this region does not return to the inside of the element due to the reflection of the first and second electrodes 3 and 4, which causes the component to overheat. - most of the current flows from the side surface of the first conductive layer of the first electrode 3 to the side of the first conductive layer: the current diffusion layer 23 is horizontally and horizontally distributed, and then flows to the area where the excess element j 22 flows downward, and flows to the first portion. The side peripheral surface of the second conductive layer 43 of the two electrodes 4 forms a passage, so that the quantum unit 22 (4) should be a region to generate photons with internal quantum effects. That is, most of the current is concentrated and diffused through the corresponding elements of the quantum unit. The light can be directly extracted from the area of the Mesa platform area of the Mesa platform area, and all the supplied currents are effectively generated in the wood, thereby effectively improving the luminance of the element. "In addition, some of the light that has not yet been directly emitted from the Mesa platform area" is again passed through the main reflection layer 212 of the block substrate 21 and the first and second electrodes of the first and second electrodes 3: The reflective layers 32, 42 form primary and secondary reflections, which compensate for the Fresnel loss' and are emitted outward from the Mesa platform area. The overall illumination brightness is increased by 12 200814355 and the heat generation problem can be avoided at the same time. Referring to FIG. 3, a second preferred embodiment of the high-brightness light-emitting diode of the present invention is similar to that described in the first preferred embodiment except that the first and first electrodes 3 and 4 are different. The first and second insulating layers 3 are in the form of 41, and since other structures have been described in detail in the foregoing description, the detailed description thereof will not be repeated here.

The first and second insulating layers 31, 41 of the first and second electrodes 3, 4 respectively have a plurality of perforations to form a predetermined image, and when electric energy is applied from the first and second electrodes 3, 4, current is diffused. The mode is shown by the imaginary line arrow in the figure, wherein most of the current is blocked by the first insulating layer 31, and the first conductive layer 33 side electrically connected from the first electrode 3' to the current spreading layer 23 is provided. After the circumferential surface passes through the flow, the scattered layer 23 is horizontally dispersed horizontally, and then vertically diffused downwardly through the lining to generate light 7L 22; a small part of the current is due to the first insulating layer 31, and the majority of the diffusion of the occlusion is formed. The effect of the channel, followed by such imaginary diffusion channels, flows down through the quantum unit 22 to produce light. Although the current is concentrated and diffused through the Mesa platform region corresponding to the component which can mainly emit light, and then the light can be directly emitted to the outside, the luminance of the light-emitting diode 2 can be improved, and the corresponding first and second electrodes can be avoided. 3, 4, when the lower area produces light and is intended to be emitted outward, it will be blocked by the first and second electrodes 3', 4' from being reflected back into the element, thereby causing internal heat problems. In the second preferred embodiment, the first and second electrodes 3, 4, the first and second are specifically designed to reduce the working life of the component. The insulating layers 31, 4i have a plurality of perforations 13 200814355

Pre-w, the effect of the diffusion conduction that causes most of the current to diffuse by the perforations is such that part of the current can be diffused through the imaginary channels, and in the region below the first and second electrodes 3, 4, Producing light, and then dispersing the current to avoid the problem of reducing the working life of the component; at the same time, in order to avoid the problem that the light generated in these regions is converted into internal heat due to the limitation of the first and second electrodes 3, 4, In the present example, similar to the above description, the second reflective layer 212 of the substrate 21 is combined with the second and second electrodes 3, 4 of the second and second electrodes 3, 4 to make the light The -secondary and secondary reflections are generated to compensate for the loss of the phenotype, and then the light is emitted directly from the corresponding PCT (10) platform region to simultaneously increase the luminance of the component. .································································································· The layer constitutes the first and second electrodes, and the enhancement of the metabolite layer by the insulating layer ensures that the current diffuses and conducts in the current diffusion layer to further concentrate the current through the quantum corresponding to the flat region 100 which can directly emit light outward. The unit 22 generates light that is directly emitted outward to effectively increase the electrical and optical redundancy of the component. At the same time, it also minimizes the generation of light corresponding to the region under the first and second electrodes that is not easy to directly emit light, thereby avoiding light generated in this region. The problem of overheating of the S component due to the blocking reflection of the first and second electrodes, thereby causing the problem of overheating of the S component; in addition, the present invention also utilizes the first, the reflective layer of the drain, and the design of the main reflective layer of the substrate, The secondary and secondary reflections of the light produced by the internal quantum effect to compensate for the loss of the Philippine sensation, so that the internally generated light can be more effectively concentrated from the Mesa platform area, and the overall component is improved. The illuminating brightness does not achieve the purpose of the present invention. The above is only the preferred embodiment of the present invention, and is not limited to the scope of the present invention. The simple equivalent changes and modifications made in the scope of the patent and the description of the invention are still within the scope of the invention. [Simplified illustration] FIG. 1 is a schematic cross-sectional view showing a conventional light-emitting diode Body, and said the state of internal current diffusion; one = 2 is a cross-sectional view, illustrating a high-brightness light-emitting diode of the present invention - a preferred embodiment, and illustrating its internal current diffusion; Figure 3 is a cross-sectional view showing the high-brightness light-emitting diode of the present invention in a preferred embodiment, and illustrating the state of internal current diffusion. 15 200814355 [Main component symbol description] 100 Mesa platform area 226 recessed hole 2 Light-emitting diode 23 current diffusion layer 21 substrate 3, 3, first electrode 211 bottom layer 31, '31, first insulating layer 212 main reflective layer 32 first reflective layer 22 quantum unit 33 Conductive layer 221 first type cladding layer 4, 4, first electrode 222 second type cladding layer 41, 41, second insulating layer 223 active layer 42 second reflective layer 224 central region 43 second conductive layer 225 outer ring region 16

Claims (1)

200814355 Patent application scope: a brightness light-emitting diode comprising a plate-shaped substrate; a quantum unit 'formed on the substrate by a gallium nitride-based semiconductor material and having a layer connected to the substrate and including a block a central zone and a first-type coating layer surrounding the outer ring zone of the central zone, an active layer formed from the top surface of the central zone of the first-type cladding layer, a layer " an active layer top surface Forming a second type of coating layer, and two sub-divisions (4): in the outer ring region of the disc-type coating layer and the concave hole on the surface of the second type coating layer, the first- and second-type coating layers are opposite to the activity The layer is formed into a quantum energy barrier to generate light by a photoelectric effect; a piece of the first electrode is disposed in a recess formed in the % region outside the first cladding layer and has a first insulating layer composed of an insulating material a layer of a first reflective layer 5 formed of a material having a high reflectance from the top surface of the first insulating layer and a layer formed of a conductive material from the top surface of the first reflective layer and ohmic with the first type of cladding layer Contacted first conductive layer; and - sheet second The pole is disposed in the surface of the second type of cladding layer: and can cooperate with the first electrode of the sheet to supply electrical energy to the quantum unit. The anode has a second insulating layer composed of an insulating material and a layer of germanium. The first reflective layer formed from the top surface of the second insulating layer has a surface reflection coefficient material and the layer is made of a conductive material from the top surface of the second reflective layer and is in ohmic contact with the second type of cladding layer. The r-th conductive layer. 2. The high-brightness light-emitting diode according to the first item of the patent scope, in the case of 2008 200835355, the § hai block substrate has one, the layer is formed by a material having a high reflection coefficient The main reflective layer on the bottom layer. 3. The high-brightness light-emitting diode according to the second aspect of the patent application, further comprising a layer of a current diffusion layer formed of a transparent and electrically conductive material. 3 4. According to the high-brightness light-emitting diode according to item 3 of the patent scope, the first and second insulating layers of the first and second electrodes are respectively selected from the group consisting of: Nitride, oxidized stone, titanium oxide, oxidation绍, Oxidation error, Zinc oxide 'oxidation, magnesium fluoride, titanium nitride. 5. According to the high-brightness light-emitting diode according to item 4 of the patent application scope, the basin: constitutes the first and second electrodes The resistance of the material of the two reflective layers is greater than the first and second conductive resistance values of the first and second electrodes. ^ Τ, the first and second conductive layers of the first and second electrodes respectively comprise at least one layer selected from the following a conductive film formed by a group consisting of gold, aluminum, silver, iridium, titanium, ruthenium, copper, platinum, palladium, rhodium, and the like. 7. According to the high brightness described in the sixth item of the application a light emitting diode, wherein the first and second reflective layers of the first and second electrodes are respectively selected from the group consisting of gold, aluminum, silver, tantalum, titanium, indium, steel, palladium, palladium, Oh, and the combination of these. 8. The high-intensity light-emitting diode according to item 7 of the patent application scope, the first and second insulating layers of the first and second electrodes respectively have a plurality of perforations for allowing current to flow through the diffusion to form a predetermined state. kind. 18