CN1377095A - Semiconductor LED on oblique substrate - Google Patents

Semiconductor LED on oblique substrate Download PDF

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CN1377095A
CN1377095A CN01112063A CN01112063A CN1377095A CN 1377095 A CN1377095 A CN 1377095A CN 01112063 A CN01112063 A CN 01112063A CN 01112063 A CN01112063 A CN 01112063A CN 1377095 A CN1377095 A CN 1377095A
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layer
light
emitting diode
ground
conductivity type
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CN1182595C (en
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郭立信
许靖豪
吴伯仁
许文士
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ZHOULEI SCIENCE & TECHNOLOGY Co Ltd
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ZHOULEI SCIENCE & TECHNOLOGY Co Ltd
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Abstract

A light-emitting diode made from compound semiconductor material includes an active region that emits light and possesses a structure of multiple quanta traps. The active region is grasped and convered by the upper and lower two layers of InGaAIP and the upper coverture layer. The epitaxial layer of INGaAIP is formed on GaAs substrate with a declining angle <111> by using method of organic metal vapour phase extrapolation (OMVPE). The electrical property of the bevelled substrate is the same with the property of the lower converture layer. There is a light beam penetration layer i.e. the current diffusion layer, which possesses the second type electrical conductivity, above the upper coverture layer of current to be diffused and for emitting light beam to be expanded.

Description

Semiconductor light-emitting-diode on the oblique substrate
The relevant a kind of semiconductor light-emitting-diode of the present invention.
Is a considerable semi-conducting material based on the alloy of InGaAlP for the manufacturing process of the light-emitting diode of wavelength between ruddiness and green glow.In 0.5(Ga 1-xAl x) 0.5P alloy and GaAs ground are lattice match (lattice match), and the direct conversion energy gap of a 1.9eV to 2.3Ev arranged, and the molecular composition of Al is greatly about between 0＜x＜0.7 in this energy gap.As the composition of Al During greatly about x～0.7 0.5(Ga 1-xAl x) 0.5P has indirect energy rank.In when the composition x of Al～1 0.5(Ga 1-xAl x) 0.5P has another energy rank indirectly, is about 2.3eV.High efficiency luminous in order to obtain, must there be powerful carrier luminous again in conjunction with (recombination) and high efficiency light-emitting diode.Based in the light-emitting diode of InGaAlP at shorter wavelength, just have between the visible light of ruddiness and yellow-green light and switch through luminous for high brightness of transducing crack always.
In addition, In 0.5(Ga 1-xAl x) 0.5P have be close to that perfect lattice is aimed at (alignment) and at GaAs on V/III/V/III family interface semiconductor substrate, the characteristic that discharge balance (charge balance) arranged, this characteristic represents that it is atom level stratum (atomic level) epitaxial growth (epitaxial growth), similarly be accurately to control multiple quantum trap (Multiple quantum well, one good standby element of thickness MQW) and composition, therefore be the epitaxial growth material of a good light-emitting diode (LED), also thereby cause In 0.5(Ga 1-xAl x) 0.5P possesses very big attraction on the visible light emitting diode manufacturing process.
Fig. 1 shows a traditional type light emitting diode construction, and structure comprises the long heterostructure of being made up of the InGaAlP alloy system at least (double heterostructure, DH), DH is by a n shape In among the figure on n shape GaAs ground 101 0.5(Ga 1-xAl x) 0.5P lower level packages coating (cladding layer) 102, do not ooze assorted active layers In 0.5(Ga 1-xAl x) 0.5 P 103, a p shape In 0.5(Ga 1-xAl x) 0.5P higher level coating layer 104, a p shape GaP current-diffusion layer 105, upper strata metal 106 and underlying metal 107 are formed.
Fig. 1 shows that a light-emitting diode is a p-n composition surface, imposes a forward bias voltage drop and makes the hole be injected into active area 103 by p shape coating layer 104 and electronics by n type coating layer 102.Active area 103 is owing to electronics radiates visible light with the hole combining again of one's respective area.Electronics and hole are injected into and cross over active area (active region) 103 as minority carrier, and can be by photism or non-photism and again in conjunction with (recombine).Its emission wavelength of LED based on InGaAlP can be by adjusting active area (In 0.5(Ga 1-xAl x) 0.5P) composition of Al and changing in 103 comes corresponding one specific emission wavelength by a correct energy gap.For example, when shorter wavelength, as gold-tinted or yellow-green light, active layers In 0.5(Ga 1-xAl x) 0.5 P 103 must be made up of for light more Al and radiates.The thickness of active layers 103 also has its importance, and is shorter than incident carrier diffusion length (carrier diffusion lenghth) usually, so that the carrier recombinant.The luminous efficiency of thicker active layers 103 can reduce because of low-density carrier.The thickness of active layers 103 is greatly between 0.3 to 0.5 μ m.Active area 103 is to inject (injection) and combine (recombination) again to produce the zone of light for carrier.The requirement of material quality of active area 103 is very high, its objective is in order to obtain high efficiency luminous.Therefore, active area 103 needs very low background intrinsic (intrinsic) impurity, and this will reduce the density of non-photism recombination center (nonradiative recombination center).It mainly is that degree of depth trap (deep traps) by active area 103 middle-high densities is caused that the height of active area 103 oozes assorted background, can cause causing the combination again of non-photism in the process that light radiates.The reaction chamber (chamber) of clean and a low impurity, for growing up to of active area be necessary.Usually, In 0.5(Ga 1-xAl x) 0.5P active layers 103 is the non-districts that mix of oozing, and can be p shape or n shape, oozes assorted density greatly about 5*10 15To 1*10 17/ cm 2Between.On the other hand, the background of active area 103 is oozed assorted degree to be increased and increases along with the composition of Al, and this is because the factor that the Al concentration increase of active area 103 causes impurity concentration to increase.
For the light divergence of shorter wavelength, the composition of Al increases in the active area 103, will follow the minimizing of the internal quantum efficiency (internal quantum efficiency) of emission light.As mentioned above, active area 103 in higher Al form, will follow the increase of rank, degree of depth position (deep level), and the combination again of non-photism can be caused in rank, degree of depth position, also just reduces luminous efficient.
N-type and p-type coating layer (102 and 104) are the source (source) of incident carrier, and than active area 103 higher energy rank are arranged, with the carrier of restriction injection and the light that sends.These coating layers need the favorable conductive rate and suitable ooze assorted concentration and enter active area 103 and reach high efficiency luminous so that enough incident carrier to be provided.Coating layer In 0.5(Ga 1-xAl x) 0.5The thickness of P is enough thick, is back to coating layer to prevent carrier by active area 103, but is unlikely thick in the emission effciency that influences LED.As a result, a large amount of emission carriers overflow to coating layer, leakage current because the non-photism of overflow carrier again in conjunction with and produce.Usually, (doube heterostructure DH) understands decay along with diminishing of wavelength (degrade) to luminous efficiency at traditional LED double-heterostructure.
On p shape coating layer 104, there is a current-diffusion layer 105 effectively to scatter for light.Current-diffusion layer 105 is that the light that one (layer) wanted active layers to be sent makes its semiconductor that penetrates away, be the equal of a window layers, and described semiconductor is penetrability for light by active area 103 light emitted wavelength.In addition, electric current diffusion window layers 105 must be scattered entering the electric current of active region 103 with coating layer (102 and 104) effectively equably, therefore needs high mix concentration and the thickness of oozing.
For overcoming above-mentioned difficulty, the light that makes that LED need design has more high efficiency when being launched by light-emitting diode, among the present invention, can put forward based on the request of the LED number of InGaAlP, to make an efficient light-emitting diode.
The purpose of this invention is to provide a kind of light-emitting diode of growing up and to make with compound semiconductor materials that improves luminous emission efficiency.
A kind of light-emitting diode according to an aspect of the present invention is characterized in, which comprises at least: a Metal Contact base; One first conductivity type GaAs ground, it is on described Metal Contact base, and described ground is cut sth. askew along＜111〉A angles, and described mis-cut angle is greater than 10 °; The one described first conductivity type InGaAlP layer, it is positioned at above the described ground; One active layers, it is positioned at above the described first conductivity type InGaAlP layer, and described active layers does not have the atom order; One second conductivity type InGaAlP layer, it is positioned at above the described active layers, and it is electrically opposite with the described first conductivity type InGaAlP layer; One window layers, it is positioned at above the described second conductivity type InGaAlP layer; And a Metal Contact footstock, it is positioned at above the described window layers.
A kind of light-emitting diode according to a further aspect of the invention is characterized in, which comprises at least: a Metal Contact base; One first conductivity type GaAs ground, it is on described Metal Contact base, and described ground is cut sth. askew along＜111〉A angles, and described mis-cut angle is greater than 10 °; One light reflector is positioned on the described ground, described light reflector ooze assorted concentration greater than 2*1017/cm2; The one described first conductivity type InGaAlP layer, it is positioned at above the described light reflector, and the described first conductivity type InGaAlP layer has one to ooze assorted concentration: between between the 0.4*1018/cm2 to 1*1018/cm2; One active layers is positioned at above the described first conductivity type InGaAlP layer, and described active layers comprises a strain In at least y(Ga 1-x1Al X1) 1-yP/In 0.5(Ga 1-x2Al X2) 0.5The P multiple quantum trap, described In y(Ga 1-x1Al X1) 1-yThe P well has one＜001〉lattice constant, it is greater than the lattice constant of the described GaAs ground of cutting sth. askew about 0.2% to 0.6%; One electron reflection layer has an In 0.5Al 0.5The P layer that is jammed, it is on described active layers, and the described layer thickness that is jammed is about between 20 to 40nm; One second conductivity type InGaAlP layer, it is positioned at above the described electron reflection layer, and it is electrically opposite with the described first conductivity type InGaAlP layer; One window layers, it is positioned at above the described second conductivity type InGaAlP layer; And a Metal Contact footstock, it is positioned at above the described window layers.
A kind of light-emitting diode according to another aspect of the invention is characterized in, which comprises at least: a Metal Contact base; One first conductivity type GaAs ground, it is on described Metal Contact base; One resilient coating, it is positioned at above the described first conductivity type GaAs ground; The one described first conductivity type InGaAlP layer, it is positioned at above the described ground; One active layers, it is positioned at above the described first conductivity type InGaAlP layer; One second conductivity type InGaAlP layer, it is positioned at above the described active layers, and it is electrically opposite with the described first conductivity type InGaAlP layer; It is positioned at one light extract layer (extraction layer) above the described second conductivity type InGaAlP layer, and described light extract layer is used for stopping and scattering the light of being dispersed out by the second conductivity type InGaAlP layer; And a Metal Contact footstock, it is positioned at above the described window layers.
A kind of light-emitting diode according to a further aspect of the present invention is characterized in, which comprises at least: a Metal Contact base; One first conductivity type GaAs ground, it is on described Metal Contact base, and described ground is cut sth. askew along＜111〉A angles, and described mis-cut angle is greater than 10 °; The one described first conductivity type InGaAlP layer, it is positioned at above the described ground; One active layers, it is positioned at above the described first conductivity type InGaAlP layer; One second conductivity type InGaAlP layer, it is positioned at above the described active layers, and it is opposite with the described first conductivity type InGaAlP layer electrically; One light extract layer (extraction layer), it is positioned at above the described second conductivity type InGaAlP layer, and described light extract layer is used for blocking the growth direction electric current and scatters light; And a Metal Contact footstock, it is positioned at above the described light extract layer.
A kind of light-emitting diode according to a further aspect of the invention is characterized in, which comprises at least: a Metal Contact base; One first conductivity type GaAs ground, it is on described Metal Contact base, and described ground is cut sth. askew along＜111〉A angles, and described mis-cut angle is greater than 10 °; One light reflector, it is on described ground; One first conductivity type InGaAlP layer, it is positioned at above the described light reflector; One active layers, it is positioned at above the described first conductivity type InGaAlP layer, and described active layers comprises a strain In at least y(Ga 1-x1Al X1) 1-yP/In 0.5(Ga 1-x2Al X2) 0.5The P multiple quantum trap, described In y(Ga 1-x1Al X1) 1-yThe P well has one＜001〉lattice constant, it is greater than the lattice constant of the described GaAs ground of cutting sth. askew about 0.2% to 0.6%; One Iny (Ga1-x1Alx1) 1-yP electron reflection layer, on described active layers, described electron reflection layer has the In0.5Al0.5P layer that is jammed, and the described layer thickness that is jammed is about between 20 to 40nm; One second conductivity type InGaAlP layer, it is positioned at above the described electron reflection layer, and it is opposite with the described first conductivity type InGaAlP layer electrically; One light extract layer (extraction layer), it is positioned at above the described second conductivity type InGaAlP layer, and described light extract layer is used for blocking the electric current of growth direction and scatters light; And a Metal Contact footstock, it is positioned at above the described light extract layer.
Adopt technique scheme of the present invention,, therefore can be made into a high efficiency light-emitting diode, have more high efficiency when light is launched by light-emitting diode because the structure with the combination of InGaAlP layer of light-emitting diode is better than conventional art.
Be clearer understanding purpose of the present invention, characteristics and advantage, will go through preferred embodiment of the present invention below.These embodiment use a particular example of the present invention in order to describe, and are not in order to limit this
Scope of invention.
The light-emitting diode schematic cross-section that Fig. 1 is traditional;
The light-emitting diode schematic cross-section of Fig. 2 first embodiment of the invention;
The light-emitting diode schematic cross-section of Fig. 3 second embodiment of the invention;
The light-emitting diode schematic cross-section of Fig. 4 third embodiment of the invention;
Take the light emitting diode of In GaAlP as the basis, its glow color can be by changing In in the active layers0.5(Ga 1-xAl x) 0.5The constituent of P alloy A l reaches the correct energy gap of a corresponding specific emission wavelength, and changes the In of active area0.5(Ga 1-xAl x) 0.5P causes energy gap width (width of the band gap) to become simultaneously Little, its structure will be tended to than orderliness (order). In order to reach identical wavelength of transmitted light, active area The Al composition need have higher content, still, so but can cause the high impurity density of active area, and cause low Emission efficiency. Arrange orderly structure, for example, atom changing because of orderliness or composition in the semiconductive thin film Change can cause the static displacement (static displacement) of atom to be created in lattice tetrahedron (tetragonal) Localized variation in the deformation is at In0.5(Ga 1-xAl x) 0.5In the P alloy system, Indium (In) have than Ga or The tetrahedron that the Al atom is bigger (tetrahedral) covalent radius (covalent radius) 9. Therefore, tetrahedron (tetrahedral) otherness of covalent radius can produce similar gathering (clustering of like species). The local deformation that the result relatively produces crystal structure shrinks and prolongation (dilation). By spinodal decomposition (spinodal Decomposition) heating power idea is positioned at the solubility of phase diagram (phase diagram) (miscibility) a certain component alloy in the energy gap can produce orderliness to out of order under a certain transition temperature Turnover. Experiment is the consideration that kinetic energy and surface texture order form with the difference of heating power theory. By us Experiment, it is basic that In0.5 (Ga1-XAlX) 0.5P film is followed spinodal decomposition thermodynamics Theory, tendency has certain order structure in various degree between growth temperature 660-770 degree. Light-emitting diodes Pipe is approximately higher than greatly 700 in the growth temperature is outside one's consideration and prolongs growth, is one aspect of the present invention. On the other hand,＜001 〉 The again growth of GaAs is＜110〉the subtabulation surface layer of direction has changeability compression and zone along exhibition. Cause For indium (Indium) has than Ga or bigger tetrahedron (tetrahedral) covalent radius of Al, at its growth face Changeability on (growing surface) prolongs and compressibility, is the suitable long tuberculosis position (energy of energy Favorable nucleation site), for In, Al or Ga, extremely be fit to their growth. This point Hinting, except above-mentioned rule and irregular transition temperature, the formation of regular texture and the surface of ground Structure is relevant. By our experiment, the degree of rule can be by at the bottom of the GaAs that uses different wrong corner cut degree Material and being improved. Regular and irregular transition temperature is to descend because of the increase of ground GaAs cutting angle. On the surface that mistake is cut the GaAs ground, periodically extend and the resurfacing zone of shrinking, can be improved by the increase of the wrong corner cut degree of ground GaAs and reduce. Found out by above result, along with the wrong corner cut of GaAs ground The increase of degree, the atom sequence rule degree in InGaAlP can reduce significantly.
Under a certain growth temperature, In0.5(Ga 1-xAl x) 0.5Regular texture is regarded as reducing a factor of quantum efficiency in the P alloy system, therefore must increase Al at In0.5(Ga 1-xAl x) 0.5The composition of P active area, obtain specific can rank the quantum well of width, therefore, can pass through In0.5(Ga 1-xAl x) 0.5The P epitaxial growth is cut in a mistake On the ground, and so that reducing to, transition temperature is lower than 700 ℃.
In addition, the In that contains Al0.5(Ga 1-xAl x) 0.5Quantum efficiency in the P multiple quantum trap can be by increasing ground Wrong corner cut degree and being improved. Cutting sth. askew more towards＜111 of GaAs ground〉the A surface, can expose the more Cation terminal step edges (cation terminated step edges). Incorporating of impurity of absorption is logical Cross a stepped trap (step traps), and and the bond between lip-deep absorption impurity and terminal ladder of growing up Shape is relevant. Cation stops step edges to be had a single bond and more weak absorption position is provided. Therefore, rank Ladder trap effect (step trapping efficiency) can along with the surface of growing up along＜111 the angle of chamfer of A Spend increase and reduce its adhesion effect. So the adding of active region impurity (for example silicon or oxygen) will be along with angle Increase and reduce. These foreign bodys can be used as the deep layer of light emitting area and the center of non-luminous again combination, And affect the emission effciency of LED. Among the present invention, take GaAs ground and mis-cut angle along person＜111 A Be equal to or greater than the 10 degree light that are regarded as launching and have better efficient.
In addition, the film light slippery take InGaAlP as the LED on basis and quality can be by long at oblique substrates GaAs structure and being improved. Be used in the past improving the applied epitaxy technology of semi-conductive surface flatness as Liquid phase epitaxial method (Liquid Phase Epitaxy, LPE) or vapour phase epitaxy method (Chemical Vapor Deposition, CVD) to improve the smoothness of film. Among the present invention, then take InGaAlP as the basis Light emitting diode (LED) is also used organic metal vapour phase epitaxy method (Organometalic Vapor Phase Epitaxy, OMVPE) long (off-cut) angle of cutting sth. askew greater than 10 ° the long ground GaAs of angle on, change Kind film light slippery. By our research, the smoothness of LED structure can be along with the increase of the wrong corner cut degree of ground And increase, the improvement of this smoothness is that the epitaxial growth on basis is especially obvious on the GaAs ground for non-matching (mismatch) heterojunction structure of 3-5 family such as GaP, AlGaP and InGaAlP. These epitaxial loayers such as GaP, The unmatched degree of lattice between AlGaP and InGaAlP alloy and the ground is approximately 0-3.6%, and with close The composition of gold is relevant. In the deposition process, the growth of film initial stage is tended to grow at ground on non-matching ground The crystal of some shapes such as island, the size of these islands is along with the non-matching degree of film and ground increases and increases Greatly. This will cause forming highdensity wire difference row (thread dislocation) on the film, and increase deposition The surface roughness of film. These highdensity crystal defects and coarse film surface can be by increasing the surface Crystalline temperature number and minimizing tuberculosis island area reach does a gradient (gradient) in the lattice paprmeter of non-matching heterojunction structure Change and be improved. Film tuberculosis is counted out to be increased and the reducing of island area, and is on the other hand in the present invention Emphasis. Can use the GaAs ground and cut sth. askew one greater than 10 ° of angles, and with an InGaAlP intermediate layer Be inserted into LED In0.5(Ga l-xAl x) 0.5Be used as between P epitaxial loayer and the window layers gradient layer reach this one Effect. Cut in mistake on (off-cut) ground, the ground step edges can increase and increase along with the wrong corner cut degree of ground. These step edges provide the tuberculosis point of a low energy position to deposit film. Therefore, the higher and face of density Long-pending littler island tuberculosis is cut the increase that can cause membrane quality on the ground and is reached more level and smooth degree in mistake, thin The change of film quality can increase the luminous delivery efficiency of LED. In addition, the smoothness of film surface can increase The scope of component manufacturing process, for example the quality of the metallic contact manufacturing of light emitting diode and encapsulation, film, send out The improvement of the efficient of light body, component manufacturing process scope (process window of device fabrication) All be that the present invention is attainable, this is by making In among the LED0.5(Ga 1-xAl x) 0.5P foundation structure is grown up in mistake Obtain on 10 ° of corner cut degree or the above GaAs ground.
The top every characteristic of summing up, first embodiment among the present invention, as shown in Figure 2, it is the profile of a light-emitting diode, comprises a light reflector and a quaternary alloy In at least 0.5(Ga 1-xAl x) 0.5P, long on n type inclination ground GaAs 208, this structure comprises 209, one n types of n type GaAs resilient coating AlAs/Al at least xGa 1-xAs-or In 0.5(Ga 1-xAl x) 0.5P is decentralized Bragg reflecting layer (distributed Bragg reflector, DBR) 210, the one n type In on basis 0.5(Ga 1-xAl x) 0.5Assorted In is not oozed in P lower level packages coating (cladding layer) 211, one strains (strain) y(Ga 1-xAl x) 1-yP/In 0.5(Ga 1-xAl x) 0.5P multiple quantum trap (multiple quantum well, MQW) 212, one p-type In 0.5(Ga 1-xAl x) 0.5The In that P higher level coating layer 213, approaches 0.5(Ga 1-xAl x) 0.5P middle be jammed layer 214, one p-type GaP or AlGaAs current spreading layer 215, one top-level metallics contact 216 contact 217 with a underlying metal.
The profile of Fig. 2 light-emitting diode is very similar to Fig. 1 traditional type double-heterostructure, except being by Fig. 2 one deformation In in Fig. 1 InGaAlP-active area 103 y(Ga 1-xAl x) 1-yP/In 0.5(Ga 1-xAl x) 0.5P multiple quantum well 212 replaces.One n-type light reflector AlAs/Al xGa 1-xAs-, AlAs/In 0.5(Ga 1-xAl x) 0.5P-or In 0.5(Ga 1-xAl x) 0.5P-is that (distributed Braggreflector, DBR) 210 pendulum are at In for basic decentralized Bragg reflecting layer 0.5(Ga 1-xAl x) 0.5The bottom of P-LED structure is to provide the light reflection.In addition, an In 0.5(Ga 1-xAl x) 0.5The P electric current be jammed the layer 214, the pendulum at p-type In 0.5(Ga 1-xAl x) 0.5 P coating layer 213 is middle with p-type GaP, AlGa or AlGaAs window layers 215.
The LED structure has the about 0.2-0.4 μ of one deck m silicon to ooze assorted GaAs resilient coating 209 among Fig. 2, and length is oozed on the assorted inclination ground 208 at silicon.GaAs resilient coating 209 is to be used for improving GaAs ground grow up lip-deep slickness and uniformity.Growth GaAs resilient coating 209 is necessary for the preferable quality of LED multiple quantum well 212 heterogeneous interface (hetero-interfaces) films.Then (distributed Bragg reflector, DBR) 210 grow on GaAs resilient coating 209 so that the light reflection to be provided GaAs resilient coating 209, one decentralized Bragg reflecting layers.The growth material in this layer light reflector is to be selected from forbidding and forming with the material that active area 212 is similar to very much by rank band height (prohibited band height) of energy rank.What the selection of this layer growth material need be considered the difference of lattice match (lattice matching), energy gap band and reflection coefficient and indivedual reflector oozes the assorted limit (doping limit of individual reflecting layer).Generally speaking, one ten to 20 Bragg reflecting layer (distributed Bragg reflector, DBR) 210 cycle can increase 1.5 times of light external quantum efficiency (external quantum efficiency of emitting light) to general LED but do not use Bragg reflecting layer (distributed Bragg reflector, situation DBR).AlAs/Al xGa 1-xThe wavelength X of the reflected wave of As Bragg reflecting layer 210 is decided by the thickness in indivedual reflector, and its functional relation the following is d=λ/4n, and n is the reflection coefficient of Bragg reflecting layer 210 each layers.The purpose of Bragg reflecting layer is to be used for reflecting the incident ray of being come in by active area 212, Al xGa 1-xThe energy gap of As must be greater than the energy gap of active area 212 to prevent the absorption of any light.
In addition, must strengthen as much as possible with the preferable reflection efficiency again of acquisition Bragg reflecting layer 210 in the layer of Bragg reflecting layer 210 each layers difference with layer reflection coefficient.But Bragg reflecting layer 210 is also being played the part of needs high density (〉=2*10 17/ cm 2) the electric current of conduction carrier inject the function of transfer layer.Because the n-type oozes the intrinsic limitation (intrinsic limitation) of assorted concentration in the Bragg reflecting layer of AlAs-ground, the restriction of Bragg reflecting layer 210 is to reach a low forward operation bias voltage and to obtain in the Bragg reflecting layer reflectivity simultaneously more than or equal to the efficient of 90-95%.Generally speaking, the cycle based on the Bragg reflecting layer (DBR) 210 of InGaAlP-is approximately between ten to 20.The standby element of another Bragg reflecting layer 210 is In 0.5(Ga 1-xAl x) 0.5P-ground alloy, it can reach higher electrical conductivity than Bragg reflecting layer 210 grounds of AlAs/AlGaAs-ground, and still, it has but been offset by growth the controlled of lattice match on the GaAs substrate.
Among Fig. 2, n-type lower level packages coating In 0.5(Ga 1-xAl x) 0.5 P 211 is used for supplying with carrier to inject active area 212 and carrier is confined to active area 212.N-type In 0.5(Ga 1-xAl x) 0.5The molecular composition of Al is greatly about between 0.7＜x＜1 in the P-coating layer 211, and relevant system with the radiation wavelength of active area 212.The thickness of n-type coating layer 211 must be thicker than the diffusion length of carrier, is diffused into coating layer to avoid carrier by active area, general n type In 0.5(Ga 1-xAl x) 0.5 P coating layer 211 is greatly about 0.3-0.8 μ m.N-type coating layer 211 oozes the difference of the assorted degree of depth in the present invention, the variation of a gradient or stage variation are arranged, and carrier density is about 5*10 17/ cm 2To 1*10 18/ cm 2Between.
Oozing of p-type coating layer 213 assorted presents gradient or phase change along with the degree of depth in the present invention, and carrier concentration is approximately 5*10 17/ cm 2To 1*10 18/ cm 2Between.The light output efficiency of LED and n-type and p-type coating layer ooze assorted concentration and section has much relations, correct In 0.5(Ga 1-xAl x) 0.5P coating layer p-n junction ooze the p-n in active area that assorted section produced connect the face position for after the electric current injection in active area efficient electronics be necessary with luminiferous the combination again in hole.The overflow meeting of any indivedual injection carriers because the position deviation that p-n connects face with ooze mix molecule in active region diffusion and cause non-emission to combine the generation at (nonradiativerecombination) center again, and cause the minimizing of the efficient of radiating light.P-type In in the present invention 0.5(Ga 1-xAl x) 0.5The thickness ratio that the low/height of P-coating layer 214 oozes assorted degree be about 0.1 0.3 between, guaranteeing carrier combination more accurately, and can not produce too big voltage drop or carrier overflow phenomena at coating layer.Good radiological unit need be from multiple quantum trap n-type far away and p-type coating layer ooze assorted density about 0.75 ~ 1*10 18/ cm 2And ooze assorted density and arrive 0.75*10 about 0.4 greatly near the lower coating layer of the n-type of multiple quantum trap and p-type 18/ cm 2
And then n type In 0.5(Ga 1-xAl x) 0.5P coating layer 211, the In of one deck deformation y(Ga 1-xAl x) 1-yP/In 0.5(Ga 1-xAl x) 0.5P (strained) multiple quantum well 212 is used as active layers in the middle of swinging in n type and p type coating layer.Be to be the efficient and the content that reduces aluminium in the quantum well that the multiple quantum trap of superlattice (superlattice) is used for increasing active layers with InGaAlP in the present invention.Quantum well structures can increase the efficient of radiating light in LED.Quantum well is formed by be jammed (the barrier with a higherband gap) of a narrow band gap " well " with a higher energy gap.As a result, the energy in electronics and hole is quantized (limitation) and can not moves freely in the electric current incident direction.But still can on the vertical plane of incident current, move freely and combination again.At multiple quantum well In y(Ga 1-xAl x) 1-yP/In 0.5(Ga 1-xAl x) 0.5Among the P 212, in the conduction band, push away short conductive strips can rank upwards, and that the carrier that is confined to valence band pushes away short valence band is can rank downward.The multiple quantum well structure can move effective wavelength to a shorter wavelength of (shift) radiating light.Therefore, the content of aluminium can reduce in a large number in the active area 212, and it is long therefore to go into the source for a specific radiating light, and the volume minor structure of LED will increase the lifetime of non-radiative reorganization, and reduces being absorbed of light radiation.In addition, multiple quantum well In y(Ga 1-xAl x) 1-yP/In 0.5(Ga 1-xAl x) 0.5The gross thickness of P 212 is about 50 to 150nm, and is in present application, littler than the thickness of heterostructure active area (200-500nm) among Fig. 2.This will cause active area to inject the increase of carrier density and accelerate light combination again.The multiple quantum well structure has reduced Al content, and the carrier lifetime of radiation reorganization has also shortened.Therefore, LED multiple quantum well active area 212 quantum efficiencies can roll up.Between 0 to 0.3, between green-gold-tinted, it adjusts with the thickness of person's quantum well 212 and the number of quantum well corresponding wavelength the aluminium ingredient of alloy between ruddiness greatly in the multiple quantum well 212.Aluminium is formed the alloy In of direct gap in multiple quantum well 0.5(Ga 1-xAl x) 0.5P, the wavelength of transmitted light of multiple quantum well 212 and the thickness of well have great association.When the thickness of multiple quantum well reduces, its conductive strips quantization carrier will effectively secondaryly can be with (sub-band) up to push away, and covalency band quantization carrier can be taken to down effective pair and pushes away.The quantization band structure of multiple quantum well 212 is quite responsive at well thick about 1 to 10nm.As a result, because the quantization of energy stage structure, wavelength can shorten when electronics combined with the hole again.In 0.5(Ga 1-xAl x) 0.5Between 1 to 10nm, the optimal luminescent efficient cycle is 10 to 50 to the general gross thickness of P alloy greatly.On the other hand, luminous internal quantum is also relevant to (well/resistance) thickness ratio that is jammed with well.General efficient carrier again in conjunction with the time, well and the ratio that is jammed greatly about 0.75 1.25 between.
Lattice deformation (lattice strain) also is the significant consideration of LED multiple quantum well 212 designs.The biaxial strain of multiple quantum well structure (biaxial strain) can rank divide valence band and degenerate (quantized band structure) in quantizing band structure.This will influence the optical characteristics and the electricity characteristic of film band structure and film substrate.Compressibility will have positive contribution to the luminous efficiency of LED with the property upheld stress.Affact the asymmetric stress of lattice of multiple quantum well 212, being equivalent to can stage structure and the rank division of valence band energy.For constrictive biaxial stress, heavy hole (heavy hole) can become a ground state (ground states) in rank, and described ground state has a lower effective mass characteristic (lower effective mass character) on the top of valence band (valence band).This compressible stress can be strengthened the motion of carrier and the combination again of the vertical plane of incident current, and cause the increase (internal quantumefficiency) of the internal quantum efficiency in the quantum well, light hole (light hole) is for the property upheld deformation biaxial stress on the other hand, be a ground state (ground state), and have the higher effective quality.Though when being subjected to stretching stress, effective mass is bigger in quantum well, electronics and hole more a spot of k spatial distribution (poor k-space) reduce spontaneous emission ratio, and can increase internal quantum like this.Therefore, compressibility all can be contributed light emission efficiency in the quantum well to some extent with the property upheld stress in multiple quantum well.According to we research with LED in the degree of not matching of other structures surpass at 1% o'clock, multiple quantum well In y(Ga 1-xAl x) 1-yP-212 can loosen.The LED lifetime is tested demonstration, greater than 1% degree of not matching (mismatch), installs easily and degenerates, and this is because inside degree of the not matching stress (internal misfit stress) that acts on the heterostructure is the source of inappropriate dislocation in multiple quantum well.And, cause point defect during operation in the manufacturing of element.Light output efficiency is upheld or shrinkage stress is limited in order to improve in quantum well, and the multiple quantum well of InGaAlP and the lattice between the GaAs ground are not matched between 0.2% to 0.6%.In the present invention, the best delivery efficiency of LED can be by prolonging about 0.3 to 0.6% crystal degree of not matching of growth direction, and the compressibility strain that produces and obtaining.
Fig. 3 shows a LED multiple quantum well structure, comprises a DBR among the figure at least, a quaternary compound In 0.5(Ga 1-xAl x) 0.5The P alloy, long on n-type inclination ground GaAs 318, described structure comprises GaAs resilient coating 319, AlAs/Al at least xGa 1-xAs-, AlAs/In 0.5(Ga 1-xAl x) 0.5P or In 0.5(Ga 1-xAl x) 0.5P-ground decentralized Bragg reflecting layer (distributed Bragg reflector, DBR) 320, one n type In 0.5(Ga 1-xAl x) 0.5P lower level packages coating 321, one deformation In y(Ga 1-xAl x) 1-yP/In 0.5(Ga 1-xAl x) 0.5P multiple quantum well 322, one In y(Ga 1-xAl x) 1-yP-ground electron reflection layer 323, one p type In 0.5(Ga 1-xAl x) 0.5P higher level coating layer 324, one thin In 0.5(Ga 1-xAl x) 0.5P electric current layer 325, one p-type GaP or p type-328 compositions of AlGaAs current spreading layer 326, one top Metal Contact 327, one substrates contact that are jammed.
Among Fig. 3, a thin type becomes be jammed layer 325 or multilayer electronic reflector 323 and is inserted into above the p-shape coating layer 324 to increase the resistances barrier height (barrier height) of coating layer.Electron reflection layer 323 also is to grow up with the OMVPE method, needs interface contrast very accurately, the thickness of layer and the accurate control of composition.Thin deformation be jammed layer 325 have one can rank be equal to or greater than coating layer can rank and put in zone and go into coating layer to improve luminous efficiency to prevent the carrier overflow near active layers 322.P-type In 0.5Al 0.5P electron reflection layer 323 is deformation (strained), and its position has suitable thickness and stress to prevent producing electrons tunnel (tunneling) effect by active region 322 near active area 322.On the other hand, the super crystal structure of electron reflection layer 323 is to be used for reflection electronic, and its thickness is greatly about N/4 deBrogile electron wavelength, and wherein N is an odd number.The maximum reflectivity of reflection electronic is by the super brilliant In of P type 0.5(Ga 1-xAl x) 0.5P/In 0.5Al 0.5The composition of P, thickness, cycle are adjusted.The In that P mixes in electron reflection layer 323 0.5(Ga 1-xAl x) 0.5P and unadulterated active region 322 quantum wells have same composition.
Work as In 0.5(Ga 1-xAl x) 0.5P/In 0.5Al 0.5The cycle of the super crystal of P increases, and the light of active area 322 penetrates efficient also to be increased.This is the reason that increases because of the reflectivity in electron reflection 323.But this phenomenon is in the scope of thickness at 2-5nm of individual other electron reflection layer, and is obvious especially when having gradient (gradient) or interim (step) thickness to increase, the In of the electron reflection layer 323 of multiple layer 0.5(Ga 1-xAl x) 0.5The varied in thickness of P (gradient), expression is by the reflected energy of the different incident high-energy electrons of active area, therefore, carrier is confined to gradient or ladder like the zone and obtain high electron impact energy, and the diversity of electron reflection layer (varietyin electron reflector) can be obtained by the gradient variation of the thickness of layer.
Among the present invention, electron reflection 323 comprises the deformation In that is jammed at least 0.5Al 0.5P then has the In near active layers 322 0.5(Ga 1-xAl x) 0.5P/In 0.5Al 0.5The overflow carrier that the super crystal structure layer of P is come by active layers with reflection, the deformation layer In that be jammed 0.5Al 0.5P thickness is approximately 20-40nm, In 0.5(Ga 1-xAl x) 0.5P/In 0.5Al 0.5About 10-40 of super crystal structure cycle of P, In 0.5(Ga 1-xAl x) 0.5P/In 0.5Al 0.5P is super, and crystal structure thickness is approximately 2-5nm, at In 0.5(Ga 1-xAl x) 0.5The super crystal structure layer of P has fixing, the thickness profile stage or gradient.
Among Fig. 3, then multiple quantum well 322 and electron reflection 323 are p-type In 0.5(Ga 1-xAl x) 0.5P-higher level coating layer 324.P-type In 0.5(Ga 1-xAl x) 0.5The effect of P coating layer 324 is that carrier is injected into active area 322, and the carrier limitation is stayed active area 322.In 0.5(Ga 1-xAl x) 0.5The Al of P coating layer 324 forms greatly about between 0.7＜x＜1, and is relevant with active area 322 radiative wavelength, at red (625nm) between yellow-green (570nm).The thickness of p-type coating layer 324 must enter coating layer with the carrier that prevents active area 322 greater than the diffusion length of injecting carrier.In addition, p type coating layer 324 must be thicker than n type coating layer 321, and this is because the diffusible relation that the p type oozes assorted element such as Zn or Mg in the LED developmental process.One typical p-type In 0.5(Ga 1-xAl x) 0.5Low coating layer 324 thickness of P are greatly between 0.7 to 1.5 μ m.Have graded or second order segmentation to ooze assorted p-type coating layer, it oozes assorted concentration at 4*10 in the present invention 17/ cm 2To 1*10 18/ cm 2Between.The light external efficiencies of LED with ooze assorted degree and n-type and p-type coating layer to ooze the degree of mixing relevant.In 0.5(Ga 1-xAl x) 0.5To ooze that assorted section combines for effective photism with p-n " correct " bonding station of active area 322 again be necessary for " correct " n-type and p type coating layer among the P-324.Cause at misalignment that the overflow of any incident carrier will engage because of p-n and the non-radiative center of active area (inter diffusion) (nonradiative recombination center) that diffuses into of oozing the assorted factor combines and lowers the efficient of light.In the present invention, there is gradient to ooze the In of assorted coating layer 0.5(Ga 1-xAl x) 0.5P 324, thickness ratio that it is high/low to ooze assorted degree between 0.1 to 0.3, with ensure coating layer accurately carrier descend or the carrier overflow in conjunction with not producing big voltage again.
Good light-emitting diode assembly need have the high assorted concentration of oozing away from the n-type of multiple quantum well 322 and p type coating layer, and (0.75 to 1*10 18/ cm 2) (0.4 to 0.75*10 for concentration 322 with there be low the oozing of a lower n-type and p type coating layer to mix near multiple quantum well 18/ cm 2Between.
Then p-type coating layer is that one deck oozes the In that assorted density approaches greater than p-type coating layer 324 0.5(Ga 1-xAl x) 0.5P intermediate layer 325, being used for guaranteeing to inject carrier can smooth-goingly pass and scatter, and for the high conductance of guaranteeing this intermediate layer in order to electric current perpendicular to efficient the scattering on the plane of its injection direction, the composition of detail interbed 325Al (x is between 0.1 to 0.5) is than p type In 0.5(Ga 1-xAl x) 0.5P coating layer 324 is also little, and will with P type coating layer lattice match.Thickness is the low-resistance channels that are used for producing the injection current vertical plane greatly about 50-100nm and ooze the assorted density intermediate current spread layer 325 higher than p-type conductance layer.In addition, intermediate layer In 0.5(Ga 1-xAl x) 0.5P-325 has an energy gap bigger than active area 322, is adsorbed by the light of active area 322 emissions preventing.But because these intermediate layer 325 very thin thickness and have one than p-type coating layer 324 high than window layers 326 low ooze assorted density, can be used as the impedance path of electric current at the be jammed layer and the electric current incident growth direction vertical plane of growth direction.Because electric current dispersion zone scope is very big, injected current density can density can reduce because scattering the increasing of panel in the element.This will cause the lifting of LED light emission efficiency, and this electric current in P type coating layer 324 and active area 322 scatters effect will be by In 0.5(Ga 1-xAl x) 0.5P be jammed the layer thickness, composition and doping level and decide typical In 0.5(Ga 1-xAl x) 0.5The doping content in the intermediate layer of P approximately is the 2-4 1-3*10 just doubly of P type coating layer 324 18And the composition of Al, this layer greatly between 0.2-0.4.
A kind of In that makes 0.5(Ga 1-xAl x) 0.5The approach that the P light-emitting diode produces the maximum function performance is at P type In 0.5(Ga 1-xAl x) 0.5The P layer adds layer window layer 326 on 325 top.Use GaP, AlGaP or AlGaAs to be used as window layers, and as the idea literature research mistake in the past of the distribution function of LED electric current, and be published in the patent documentation.GaP or GaAsP have a relative light-permeable energy gap for the light that is come out by 322 radiation of LED active area.Utilizing the OMVPE method to grow up among the present invention in direction＜111 of cutting sth. askew〉the LED structure comprises P type GaP, AlGaP or AlGaAs window layers 326 on the GaAs ground of angle.This idea derives from 1,976 one pieces of documents, epitaxial deposition AlGaAs, GaP or other family's semiconductor surface with LPE or CVD epitaxial growth mode to improve the flatness of deposit film.And in the present invention, III-V compounds of group such as GaP, Al xGa 1-xP (x＜1) and Al yGa 1-y(0.5＜y) radiates wavelength with the growth of MOVPE method at LED ought disperse injection current as window layers to As in the 650-565nm scope, because they are transparent for radiation wavelength 650-565nm; In addition, these three kinds of GaP, Al xGa 1-xP (x＜0.1) and Al yGa 1-y(0.5＜y) high-dopant concentration (capacity) also is to select one of factor of considering to As, and they can be with heavily oozing assorted density (＞2*10 18/ cm 2) reach wider electric current and scatter.When incident carrier (the oozing assorted degree) increase of window layers, the efficient of LED also increases.This is because along with the increase of oozing assorted concentration, and injecting carrier in the window layers 326 also can increase along being parallel to the assorted degree of oozing of each laminar surface direction.Typical window layers 326 is oozed assorted concentration greatly about 3-8*10 18/ cm 2Between.But window layers 326 is oozed assorted degree and is higher than 1*10 19/ cm 2Have lattice defect and produce, and the lifetime that can lower LED.In addition, luminous efficiency also has relation with the thickness of window layers 326.When window layers 326 thickness increase because than scatter area and all can be increased by the light that the LED side sheds of the electric current of width, the output of LED also can increase.Heavily ooze assorted degree (＞1*10 18/ cm 2) GaP, Al xGa 1-xP (x＜0.1) and Al yGa 1-yAs (0.7＜y) and the window layers of thickness between 10-15 μ m continued to use in the present invention, the 630nm wavelength, brightness reaches the LED of 60mcd; 590nm wavelength, brightness reach the LED of 100mcd; 572nm wavelength, brightness reach the LED of 40mcd.
Fig. 4 is one with In y(Ga 1-xAl x) 1-yP is basis and with the LED component structure light-emitting diode of the superlattice of (001) lattice constant of gradient or stepped, comprises a quaternary compound In among the figure at least 0.5(Ga 1-xAl x) 0.5The decentralized Bragg reflecting layer (DBR) 431 of P alloy, long on n-type inclination ground GaAs429.Described element comprises a n type GaAs resilient coating 430, one decentralized Bragg reflecting layers (DBR) 431, one n type In at least 0.5(Ga 1-xAl x) 0.5P lower layers packet coating 43, one deformation In y(Ga 1-xAl x) 1-yP/In 0.5(Ga 1-xAl x) 0.5P multiple quantum well 433, one In y(Ga 1-xAl x) 1-yP ground electron reflection 434, one p type In 0.5(Ga 1-xAl x) 0.5The In that P higher level coating layer 435, approaches 0.5(Ga 1-xAl x) 0.5The P electric current layer 436, that is jammed has the p type In that gradient form to change y(Ga 1-xAl x) 1-yP alloy superlattice structure 437, the one p type GaP or 439, one ends of p type AlGaP current spreading layer 438, one top-level metallics contact, belong to Metal Contact 440 and form.
One deck light extract layer (light extraction layer) is arranged among Fig. 4, in fact described light extract layer comprises three layers, from bottom to top be respectively be jammed layer 436, lattice gradient layer 437 and window layers 438 of electric current, the main function of light extract layer is to stop the light that is radiated out by following p type InGaAlP layer, and makes these light carry out more efficient radiation.Whole framework is as follows among Fig. 4, and a p type In is arranged y(Ga 1-xAl x) 1-yP (001) lattice constant gradient or stepped superlattice for basis 437 pendulum in the middle of intermediate current is jammed layer 436 and p type window layers 438.P type In y(Ga 1-xAl x) 1-yThe superlattice 437 that P has the variation of gradient composition are to be used for In 0.5(Ga 1-xAl x) 0.5Between P alloy 436 and the p type GaP window layers 438 as the usefulness of gradient layer.GaP window layers 438 and In 0.5(Ga 1-xAl x) 0.5P alloy layer 436 the lattice constant of being jammed differs greatly between 3.6%, and GaP/In 0.5(Ga 1-xAl x) 0.5The critical thickness of the heterostructure of P is greatly between 5-10nm.The GaP epitaxial loayer can be at In like this 0.5(Ga 1-xAl x) 0.5The P intermediate current is jammed and forms the crystal of shape such as island on the layer 436.When these epitaxial crystal islands in conjunction with after because the crystal of the merging one highdensity striped dislocation of these extension islands can be created in above the GaP window layers 438, and cause rough surface.These defectives can worsen the quality of film and the function of LED element.Highdensity crystal defect can cause the light absorbent core in window layers, and reduces the external efficiencies of light and lower its lifetime.In addition, these lattice defects can increase manufacturing process and packing as the difficulty of routing, contact point.Therefore, making the unmatched heterostructure GaP/In of lattice 0.5(Ga 1-xAl x) 0.5During P, must think on this.One has the p type In of the composition of In and Al graded y(Ga 1-xAl x) 1-yThe super crystal 4 37 of P is the difference that is used for regulating the lattice constant between Ga and the InGaAlP, also is some of the present invention simultaneously, and In and Al form (x and y) at In y(Ga 1-xAl x) 1-yIn the super crystal structure 437 of P ground is with graded, and thickness then is 0 to 100 between the 300nm, and its growth speed and has a high V/III family ratio greater than about 100 greatly between 0.05 to 0.2 μ m/ hour.In y(Ga 1-xAl x) 1-yP ground gradient layer 437 keeps 2 to 4 times greater than p type In 0.5(Ga 1-xAl x) 0.5P coating layer 435 ooze assorted concentration.
The above is preferred embodiment of the present invention only, is not in order to limit the present invention; All other do not break away from the equivalence of being finished under the disclosed spirit and changes or replacement, all should be included in the scope of patent protection of the present invention.

Claims (66)

1. a light-emitting diode is characterized in that, which comprises at least:
One Metal Contact base;
One first conductivity type GaAs ground, it is on described Metal Contact base, and described ground is cut sth. askew along＜111〉A angles, and described mis-cut angle is greater than 10 °;
The one described first conductivity type InGaAlP layer, it is positioned at above the described ground;
One active layers, it is positioned at above the described first conductivity type InGaAlP layer, and described active layers does not have the atom order;
One second conductivity type InGaAlP layer, it is positioned at above the described active layers, and it is electrically opposite with the described first conductivity type InGaAlP layer;
One window layers, it is positioned at above the described second conductivity type InGaAlP layer; And
One Metal Contact footstock, it is positioned at above the described window layers.
2. light-emitting diode as claimed in claim 1 is characterized in that, also comprises a GaAs resilient coating, and it is between described ground and the described first conductivity type InGaAlP layer.
3. light-emitting diode as claimed in claim 2 is characterized in that, the thickness of described resilient coating is between 0.2 to 0.5 μ m.
4. light-emitting diode as claimed in claim 1 is characterized in that, also comprises a reflection layer, and it is positioned on the described ground, described reflection layer ooze assorted concentration greater than 2*10 17/ cm 2
5. light-emitting diode as claimed in claim 4 is characterized in that, described reflection layer has a reflection wavelength α, and (α=β-5nm or α=β+5nm) and carrier are electrically identical with described ground near the wavelength β of described active area for its.
6. light-emitting diode as claimed in claim 4 is characterized in that described reflection layer is to be selected from by AlAs/Al X1Ga 1-x1As-ground (x1 〉=0.5), In 0.5(Ga 1-x2Al X2) 0.5P-ground (x2 〉=0.1) and AlAs/In 0.5(Ga 1-x2Al X2) 0.5The superlattice structure of group's ground of P-is formed.
7. light-emitting diode as claimed in claim 6 is characterized in that, the composition x1 of described aluminium and x2 at wavelength of transmitted light greater than 630nm, x1 less than 0.6 and x2 greater than 0.1; At wavelength of transmitted light greater than 590nm, x1 less than 0.7 and x2 greater than 0.2; At wavelength of transmitted light greater than 570nm, x1 less than 0.8 and x2 greater than 0.3.
8. light-emitting diode as claimed in claim 6 is characterized in that described reflection layer is to be selected from by AlAs/Al xGa 1-xAs-ground In 0.5(Ga 1-xAl x) 0.5The P-ground is with AlAs/In 0.5(Ga 1-xAl x) 0.5The super crystal structure of group of P-is formed, and described super each layer of crystal structure is not less than 0.15 with the reflection coefficient difference of interlayer.
9. light-emitting diode as claimed in claim 4 is characterized in that, the lattice degree of not matching of described light reflector and described ground is less than 0.3%.
10. light-emitting diode as claimed in claim 1 is characterized in that, the described first conductivity type InGaAlP layer oozes assorted concentration at 0.4*10 18/ cm 2To 1*10 18/ cm 2Between.
11. light-emitting diode as claimed in claim 10 is characterized in that, the described section of mixing that oozes comprises that at least a low/height oozes assorted concentration rate: between 0.1 to 0.5.
12. light-emitting diode as claimed in claim 1 is characterized in that, described active layers comprises the In of a strain at least y(Ga 1-x1Al X1) 1-yP/In 0.5(Ga 1-x2Al X2) 0.5P multiple quantum trap structure, described multiple quantum trap structure has an In y(Ga 1-x1Al X1) 1-yP＜001〉lattice constant, it is than described oblique substrate GaAs＜001〉lattice constant big 0.2% to 0.6% between.
13. light-emitting diode as claimed in claim 12 is characterized in that, thickness is than between 0.75-1.25 between described strain multiple quantum trap layer and the layer.
14. light-emitting diode as claimed in claim 1 is characterized in that, also comprise in the electron reflection layer, an In 0.5Al 0.5The P layer that is jammed, it is on described active layers, and the described layer thickness that is jammed is between 20-40nm.
15. light-emitting diode as claimed in claim 14 is characterized in that, described electron reflection layer comprises In at least 0.5(Ga 1-xAl x) 0.5P/In 0.5Al 0.5The super crystal structure of P, it is inserted between described active area and described the 2nd InGaAlP layer.
16. light-emitting diode as claimed in claim 14 is characterized in that, the growth layer that described electron reflection layer is selected from by fixing, stage and graded is combined the about 2-5nm of each layer thickness.
17. light-emitting diode as claimed in claim 4 is characterized in that, a described InGaAlP layer has a gradient variation, and described gradient variation section is at 0.4*10 18/ cm 2To 1*10 18/ cm 2Between.
18. light-emitting diode as claimed in claim 17 is characterized in that, described gradient variation section comprises that also a low/height oozes assorted concentration rate: between 0.1 to 0.5.
19. light-emitting diode as claimed in claim 18 is characterized in that, described active region comprises a strain (strain) In at least y(Ga 1-x1Al X1) 1-yP/In 0.5(Ga 1-x2Al X2) 0.5The P multiple quantum trap, described In y(Ga 1-x1Al X1) 1-yThe P well has one＜001〉lattice constant, it is greater than the lattice constant of the described GaAs ground of cutting sth. askew about 0.2% to 0.6%.
20. light-emitting diode as claimed in claim 19 is characterized in that, the thickness ratio between described strain (strained) multiple quantum trap layer and the layer is about between 0.75 to 1.25.
21. light-emitting diode as claimed in claim 19 is characterized in that, also comprises an electron reflection layer, described electron reflection layer has an In 0.5Al 0.5The P layer that is jammed, it is on described active layers, and the described layer thickness that is jammed is about between 20 to 40nm.
22. light-emitting diode as claimed in claim 21 is characterized in that, described electron reflection layer comprises In at least 0.5(Ga 1-xAl x) 0.5P/In 0.5Al 0.5The super crystal structure of P, it is inserted between described active layers and the 2nd InGaAlP layer.
23. light-emitting diode as claimed in claim 21 is characterized in that, the growth layer that described electron reflection layer is selected from by fixing, stage and graded is combined, and each layer thickness is about between the 2-5nm.
24. light-emitting diode as claimed in claim 21 is characterized in that, described light-emitting diode be utilize the organic metal vapour phase epitaxy method in a reaction chamber with temperature less than growing up under 750 Celsius temperatures.
25. a light-emitting diode is characterized in that, which comprises at least:
One Metal Contact base;
One first conductivity type GaAs ground, it is on described Metal Contact base, and described ground is cut sth. askew along＜111〉A angles, and described mis-cut angle is greater than 10 °;
One light reflector is positioned on the described ground, described light reflector ooze assorted concentration greater than 2*10 17/ cm 2
The one described first conductivity type InGaAlP layer, it is positioned at above the described light reflector, and the described first conductivity type InGaAlP layer has one to ooze assorted concentration: between 0.4*10 18/ cm 2To 1*10 18/ cm 2Between;
One active layers is positioned at above the described first conductivity type InGaAlP layer, and described active layers comprises a strain In at least y(Ga 1-x1Al X1) 1-yP/In 0.5(Ga 1-x2Al X2) 0.5The P multiple quantum trap, described In y(Ga 1-x1Al X1) 1-yThe P well has one＜001〉lattice constant, it is greater than the lattice constant of the described GaAs ground of cutting sth. askew about 0.2% to 0.6%;
One electron reflection layer has an In 0.5Al 0.5The P layer that is jammed, it is on described active layers, and the described layer thickness that is jammed is about between 20 to 40nm;
One second conductivity type InGaAlP layer, it is positioned at above the described electron reflection layer, and it is electrically opposite with the described first conductivity type InGaAlP layer;
One window layers, it is positioned at above the described second conductivity type InGaAlP layer; And
One Metal Contact footstock, it is positioned at above the described window layers.
26. light-emitting diode as claimed in claim 25 is characterized in that, also comprises a GaAs resilient coating, it is at described ground and above the described InGaAlP layer.
27. light-emitting diode as claimed in claim 26 is characterized in that, the thickness of described resilient coating is between 0.2 to 0.5 μ m.
28. light-emitting diode as claimed in claim 25, it is characterized in that, there is a reflection wavelength α in described light reflector, and it approaches described active layers wavelength β and makes that (α=β-5nm or α=β+5nm), the conductivity of its carrier and described active layers tool are same electrically.
29. light-emitting diode as claimed in claim 25 is characterized in that, described reflection layer is to be selected from by AlAs/Al X1Ga 1-x1As-ground (x1 〉=0.5), In 0.5(Ga 1-x2Al X2) 0.5P-ground (x2 〉=0.1), and AlAs/In 0.5(Ga 1-x2Al X2) 0.5The super crystal structure of group's ground of P-constitutes.
30. light-emitting diode as claimed in claim 29 is characterized in that, described aluminium divides subconstiuent to form x1 and x2, when wavelength greater than 630nm, x1 less than 0.6 and x2 greater than 0.1; When wavelength greater than 590nm, x1 less than 0.7 and x2 greater than 0.2; When wavelength greater than 570nm, x1 less than 0.8 and x2 greater than 0.3.
31. light-emitting diode as claimed in claim 29 is characterized in that, described light reflector is selected from by AlAs/Al xGa 1-xAs-base (based) ground, In 0.5(Ga 1-xAl x) 0.5P-ground, and AlAs/In 0.5(Ga 1-xAl x) 0.5The super crystal structure of group's ground of P-constitutes, and the reflection coefficient difference of each layer is not less than 0.15.
32. light-emitting diode as claimed in claim 25 is characterized in that, the lattice degree of not matching of described light reflector and described ground is less than 0.3%.
33. light-emitting diode as claimed in claim 25 is characterized in that, the described section of mixing that oozes comprises that also a low/height oozes the thickness ratio of assorted concentration: between 0.1 to 0.5.
34. light-emitting diode as claimed in claim 25 is characterized in that, described strain multiple quantum well (strained multi-quantum well) thickness is than between 0.75 to 1.25.
35. light-emitting diode as claimed in claim 25 is characterized in that, described electron reflection layer comprises In at least 0.5(Ga 1-xAl x) 0.5P/In 0.5Al 0.5The super crystal structure of P, it is inserted in the middle of described active layers and described the 2nd InGaAlP layer.
36. light-emitting diode as claimed in claim 25 is characterized in that, described electron reflection layer comprises at least by fixing, ladder and graded thickness and being formed that each layer thickness is approximately 2 to 5nm.
37. light-emitting diode as claimed in claim 25 is characterized in that, described light-emitting diode is to spend under the Celsius temperatures to be lower than 750 in a reaction chamber (chamber), uses the organic metal vapour phase epitaxy method and grows up on described ground.
38. a light-emitting diode is characterized in that, which comprises at least:
One Metal Contact base;
One first conductivity type GaAs ground, it is on described Metal Contact base;
One resilient coating, it is positioned at above the described first conductivity type GaAs ground;
The one described first conductivity type InGaAlP layer, it is positioned at above the described ground;
One active layers, it is positioned at above the described first conductivity type InGaAlP layer;
One second conductivity type InGaAlP layer, it is positioned at above the described active layers, and it is electrically opposite with the described first conductivity type InGaAlP layer;
It is positioned at one light extract layer (extraction layer) above the described second conductivity type InGaAlP layer, and described light extract layer is used for stopping and scattering the light of being dispersed out by the second conductivity type InGaAlP layer; And
One Metal Contact footstock, it is positioned at above the described window layers.
39. light-emitting diode as claimed in claim 38 is characterized in that, described ground is cut sth. askew along＜111〉A angles, and described mis-cut angle is greater than 10 °.
40. light-emitting diode as claimed in claim 38 is characterized in that, described light extract layer (extraction layer) comprises at least:
The one electric current layer that is jammed, it is on described the 2nd InGaAlP layer, and the described electric current layer that is jammed comprises the In of the one and second conductivity type InGaAlP same sex at least 0.5(Ga 1-xAl x) 0.5P layer, described electric current be jammed the layer thickness be 10-100nm;
One gradient layer, it is positioned at described electric current is jammed above the layer, to relax described electric current the be jammed layer and the then otherness of the lattice constant of top one deck; And
One window layers, it is positioned at above the described gradient layer with spread current.
41. a light-emitting diode is characterized in that, which comprises at least:
One Metal Contact base;
One first conductivity type GaAs ground, it is on described Metal Contact base, and described ground is cut sth. askew along＜111〉A angles, and described mis-cut angle is greater than 10 °;
The one described first conductivity type InGaAlP layer, it is positioned at above the described ground;
One active layers, it is positioned at above the described first conductivity type InGaAlP layer;
One second conductivity type InGaAlP layer, it is positioned at above the described active layers, and it is opposite with the described first conductivity type InGaAlP layer electrically;
One light extract layer (extraction layer), it is positioned at above the described second conductivity type InGaAlP layer, and described light extract layer is used for blocking the growth direction electric current and scatters light; And
One Metal Contact footstock, it is positioned at above the described light extract layer.
42. light-emitting diode as claimed in claim 41 is characterized in that, described light extract layer comprises at least:
The one electric current layer that is jammed, it is on the described second conductivity type InGaAlP layer, and the described electric current layer that is jammed comprises the In of the one and second conductivity type InGaAlP layer same sex at least 0.5(Ga 1-xAl x) 0.5P layer, described electric current be jammed the layer thickness be 10-100nm;
One gradient layer, it is positioned at described electric current is jammed above the layer, in order to relax described electric current the be jammed layer and the then otherness of the lattice constant of top one deck; And
One window layers, it is positioned at above the described gradient layer with spread current.
43. light-emitting diode as claimed in claim 42 is characterized in that, the described electric current layer that is jammed comprises the In of one second conductivity at least 0.5(Ga 1-xAl x) 0.5The P-layer, the In of described second conductivity 0.5(Ga 1-xAl x) 0.5The assorted density of oozing of P-layer is approximately higher than the assorted density 2-4 of oozing of a described InGaAlP layer greatly doubly.
44. light-emitting diode as claimed in claim 42 is characterized in that, described second conductivity type current be jammed the layer In 0.5(Ga 1-xAl x) 0.5It is between 0.1 to 0.5 that P aluminium divides subconstiuent to form x.
45. light-emitting diode as claimed in claim 42 is characterized in that, the energy rank of described light extract layer (comprising three layers) are higher than the energy rank of described active area.
46. light-emitting diode as claimed in claim 42 is characterized in that, described gradient layer has one to ooze assorted concentration: be jammed between the layer between the described window layers and second conductivity.
47. light-emitting diode as claimed in claim 42 is characterized in that, the assorted concentration of oozing of described window layers has a stage or gradient type variation: between 2*10 18/ cm 2To 8*10 18/ cm 2Between.
48. light-emitting diode as claimed in claim 47 is characterized in that, to ooze assorted concentration away from window layers/coating layer interface described low ooze assorted concentration ratio near window layers/coating layer interface described for described window layers.
49. light-emitting diode as claimed in claim 42 is characterized in that, described light-emitting diode be utilize the organic metal vapour phase epitaxy method in a reaction chamber with temperature less than growing up under the Celsius temperature 750 degree conditions.
50. a light-emitting diode is characterized in that, which comprises at least:
One Metal Contact base;
One first conductivity type GaAs ground, it is on described Metal Contact base, and described ground is cut sth. askew along＜111〉A angles, and described mis-cut angle is greater than 10 °;
One light reflector, it is on described ground;
One first conductivity type InGaAlP layer, it is positioned at above the described light reflector;
One active layers, it is positioned at above the described first conductivity type InGaAlP layer, and described active layers comprises a strain In at least y(Ga 1-x1Al X1) 1-yP/In 0.5(Ga 1-x2Al X2) 0.5The P multiple quantum trap, described In y(Ga 1-x1Al X1) 1-yThe P well has one＜001〉lattice constant, it is greater than the lattice constant of the described GaAs ground of cutting sth. askew about 0.2% to 0.6%;
One In y(Ga 1-x1Al X1) 1-yP electron reflection layer, on described active layers, described electron reflection layer has an In 0.5Al 0.5The P layer that is jammed, the described layer thickness that is jammed is about between 20 to 40nm;
One second conductivity type InGaAlP layer, it is positioned at above the described electron reflection layer, and it is opposite with the described first conductivity type InGaAlP layer electrically;
One light extract layer (extraction layer), it is positioned at above the described second conductivity type InGaAlP layer, and described light extract layer is used for blocking the electric current of growth direction and scatters light; And
One Metal Contact footstock, it is positioned at above the described light extract layer.
51. light-emitting diode as claimed in claim 50 is characterized in that, described light-emitting diode be utilize the organic metal vapour phase epitaxy method in a reaction chamber with temperature less than growing up under 750 Celsius temperatures.
52. light-emitting diode as claimed in claim 50 is characterized in that, described light extract layer (extraction layer) comprises at least:
The one electric current layer that is jammed, it is on described the 2nd InGaAlP layer, and the described electric current layer that is jammed comprises the In of the one and second conductivity type InGaAlP layer same sex 0.5(Ga 1-xAl x) 0.5P layer, described electric current be jammed the layer thickness be 10-100nm;
One gradient layer, it is positioned at described electric current and is jammed above the layer; And
One window layers, it is positioned at above the described gradient layer.
53. light-emitting diode as claimed in claim 50 is characterized in that, also comprises a light reflector, it is positioned on the described ground, described light reflector ooze assorted concentration greater than 2*10 17/ cm 2
54. light-emitting diode as claimed in claim 50 is characterized in that, there is a reflection wavelength α in described light reflector, and (α=β-5nm or α=β+5nm) and its be identical with described ground electrically near the wavelength β of described active area for its.
55. light-emitting diode as claimed in claim 50 is characterized in that, described reflection layer is selected from by AlAs/Al X1Ga 1-x1As-ground (x1 〉=0.5), In 0.5(Ga 1-x2Al X2) 0.5P-ground (x2 〉=0.1) and AlAs/In 0.5(Ga 1-x2Al X2) 0.5The superlattice structure of group's ground of P-is formed.
56. light-emitting diode as claimed in claim 55 is characterized in that, described aluminium divides subconstiuent to form x1 and x2, when wavelength greater than 630nm, x1 less than 0.6 and x2 greater than 0.1; When wavelength greater than 590nm, x1 less than 0.7 and x2 greater than 0.2; When wavelength greater than 570nm, x1 less than 0.8 and x2 greater than 0.3.
57. light-emitting diode as claimed in claim 50 is characterized in that, described light reflector is selected from by AlAs/Al xGa 1-xThe As-based ground, In 0.5(Ga 1-xAl x) 0.5P-ground, and AlAs/In 0.5(Ga 1-xAl x) 0.5The super crystal structure of group's ground of P-constitutes, and the reflection coefficient difference of each layer is not less than 0.15.
58. light-emitting diode as claimed in claim 50 is characterized in that, the lattice degree of not matching of described light reflector and described ground is less than 0.3%.
59. light-emitting diode as claimed in claim 50 is characterized in that, a described InGaAlP layer has the assorted process of oozing of a gradient variation, and described gradient variation section is at 0.4*10 18/ cm 2To 1*10 18/ cm 2Between.
60. light-emitting diode as claimed in claim 50 is characterized in that, described light extract layer (extraction layer) comprises at least:
The one electric current layer that is jammed, it is on described the 2nd InGaAlP layer, and the described electric current layer that is jammed comprises the In of the one and second conductivity type InGaAlP layer same sex 0.5(Ga 1-xAl x) 0.5P layer, described electric current be jammed the layer thickness be 10-100nm;
One gradient layer, it is positioned at described electric current is jammed above the layer, in order to relax described electric current the be jammed layer and the then otherness of the lattice constant of top one deck; And
One window layers, it is positioned at above the described gradient layer with spread current.
61. light-emitting diode as claimed in claim 60 is characterized in that, the described electric current layer that is jammed comprises the In of one second conductivity at least 0.5(Ga 1-xAl x) 0.5The P-layer, the In of described second conductivity 0.5(Ga 1-xAl x) 0.5The assorted density of oozing of P-layer is approximately higher than an InGaAlP layer 2-4 greatly doubly.
62. light-emitting diode as claimed in claim 60 is characterized in that, described second conductivity type current be jammed the layer In 0.5(Ga 1-xAl x) 0.5It is between 0.1 to 0.5 that P aluminium divides subconstiuent to form x.
63. light-emitting diode as claimed in claim 60 is characterized in that, described electric current be jammed layer can rank be higher than described active area can rank.
64. light-emitting diode as claimed in claim 60 is characterized in that, described gradient layer has one to ooze assorted concentration: be jammed between the layer between the described window layers and second conductivity.
65. light-emitting diode as claimed in claim 60 is characterized in that, described window layers has a stage or gradient type variation: between 2*10 18/ cm 2To 8*10 18/ cm 2Between.
66. light-emitting diode as claimed in claim 60 is characterized in that, to ooze assorted concentration away from window layers/coating layer interface described low ooze assorted concentration ratio near window layers/coating layer interface described for described window layers.
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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102185053A (en) * 2011-04-02 2011-09-14 映瑞光电科技(上海)有限公司 Light-emitting diode and manufacturing method thereof
CN105304739A (en) * 2014-05-21 2016-02-03 阿聚尔斯佩西太阳能有限责任公司 Solar cell stack
CN109994582A (en) * 2018-01-02 2019-07-09 山东浪潮华光光电子股份有限公司 A kind of dbr structure reducing GaAs base epitaxial wafer angularity
CN112038456A (en) * 2015-02-10 2020-12-04 晶元光电股份有限公司 Light emitting element
CN113013302A (en) * 2021-02-26 2021-06-22 东莞市中麒光电技术有限公司 Preparation method of InGaN-based red light LED chip structure

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102185053A (en) * 2011-04-02 2011-09-14 映瑞光电科技(上海)有限公司 Light-emitting diode and manufacturing method thereof
CN105304739A (en) * 2014-05-21 2016-02-03 阿聚尔斯佩西太阳能有限责任公司 Solar cell stack
CN105304739B (en) * 2014-05-21 2017-11-07 阿聚尔斯佩西太阳能有限责任公司 Solar cell is stacked
CN112038456A (en) * 2015-02-10 2020-12-04 晶元光电股份有限公司 Light emitting element
CN109994582A (en) * 2018-01-02 2019-07-09 山东浪潮华光光电子股份有限公司 A kind of dbr structure reducing GaAs base epitaxial wafer angularity
CN113013302A (en) * 2021-02-26 2021-06-22 东莞市中麒光电技术有限公司 Preparation method of InGaN-based red light LED chip structure

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