660 results about "Quantum well" patented technology

The invention provides a distributed feedback laser with a double-layer grating structure, and relates to the technical field of lasers, the laser forms an InGaAlAs multi-quantum well active region, an upper sampling grating layer and a lower phase shift grating layer on an n-type InP substrate in sequence, the upper grating layer is designed based on a reconstruction equivalent chirp technology, and the lower phase shift grating layer is designed based on a reconstruction equivalent chirp technology. Two sections of asymmetric modulation areas with sampling periods linearly gradually changing in opposite directions are arranged in the axial direction of the resonant cavity, and the lower grating layer is a quarter-wave phase shift grating matched with the period of the upper seed grating. Through the synergistic effect of equivalent phase modulation and phase shift generated by the double-layer grating, the photon density distribution in the cavity can be improved, the longitudinal space hole burning effect can be weakened, the sensitivity to end face phase fluctuation can be reduced, high single-mode power and large modulation bandwidth can be realized in a wide temperature range, and the double-layer grating is suitable for a high-speed optical communication and coarse wavelength division multiplexing transmission system.

The invention relates to the technical field of chip preparation, and provides a chip based on an annular photonic crystal and a preparation method thereof. The preparation method comprises the following steps: growing a nucleating layer on a substrate; growing a superlattice structure on one side, away from the substrate, of the nucleating layer; sequentially growing an n-type coating layer, an n-type waveguide layer, a quantum well and a p-type electron blocking layer on one side, deviating from the nucleating layer, of the superlattice structure; etching a plurality of annular cavities on the p-type electron barrier layer to form an annular photonic crystal; growing a p-type extension contact layer on one side, deviating from the quantum well, of the p-type electron blocking layer; and carrying out in-situ annealing treatment. According to the preparation method, the directivity of the photonic band gap can be effectively adjusted, uniform light waves in all directions on the side face can be formed, so that leakage of laser from a non-light-emitting area on the side face is restrained, the light emitting efficiency is improved, the annular photonic crystals are periodically distributed, and the light beam quality is effectively guaranteed.

The invention provides a semiconductor laser chip with a current modulation function and a preparation method, and relates to the field of semiconductor laser chips, and the semiconductor laser chip comprises a substrate layer, an n-type limiting layer, an n-type waveguide layer, a quantum well active region, a p-type waveguide layer, a first p-type limiting layer, a second p-type limiting layer and a contact layer which are sequentially stacked from bottom to top, the anti-reflection cavity surface and the high-reflection cavity surface are arranged on the two opposite sides of the second p-type limiting layer, the functional area is arranged between the anti-reflection cavity surface and the high-reflection cavity surface and comprises a current injection sub-area and a current blocking sub-area, the current injection sub-area is provided with a plurality of injection tips, the current blocking sub-area is provided with a plurality of blocking tips, and the injection tips and the blocking tips are arranged on the first p-type limiting layer. The injection tip is arranged between any two adjacent blocking tips; two grooves formed in the first p-type limiting layer penetrate through the second p-type limiting layer and the contact layer, and the two grooves are located in the two opposite sides of the current injection sub-region and the current blocking sub-region. According to the semiconductor laser chip, the light emitting power and the light beam quality of the semiconductor laser chip can be improved.

The invention discloses a deep ultraviolet LED epitaxial structure, a deep ultraviolet LED device comprising the same and a preparation method, and the epitaxial structure sequentially comprises a sapphire substrate, an AlN nanowire array layer, an AlN intrinsic layer and an AlGaN light-emitting structure layer from bottom to top. The AlGaN light-emitting structure layer further comprises an n-type AlGaN electron injection layer, a quantum well active layer, a p-type AlGaN electron blocking layer and other device structures. According to the invention, the vertically arranged AlN nanowire array is introduced to replace a traditional AlN buffer layer, so that lattice mismatching stress caused by a substrate is significantly released, and the dislocation density of an epitaxial layer is effectively reduced; meanwhile, the introduction of the AlN intrinsic layer further flattens the epitaxial interface and optimizes the lattice quality, thereby providing a high-quality template for the growth of a high-performance AlGaN material. The epitaxial structure is suitable for an LED device in a deep ultraviolet band, and the crystal quality, the electrical property and the luminous efficiency of the device can be improved.

The invention discloses a thermal-decay-resistant red light Micro LED epitaxial structure and a preparation method thereof. The epitaxial structure sequentially comprises a substrate layer, an n-type buffer layer, an n-type etching barrier layer, an n-type ohmic contact layer, an n-type limiting layer, a quantum well structure, a p-type spacer layer, a p-type electron barrier layer and a p-type ohmic contact layer from bottom to top. Wherein the quantum well structure is formed by alternating 1-5 pairs of InGaP well layers and three-section type p-type AlGaInP barrier layers, and the three sections of barrier layers adopt gradient energy level design and are all subjected to p-type doping; according to the invention, the problems of carrier loss and low recombination efficiency at high temperature in the prior art are solved by blocking electron overflow through the gradient energy level barrier and supplementing the hole concentration through p-type doping, so that the 85 DEG C external quantum efficiency attenuation rate is less than or equal to 10%, the service life is prolonged to more than 50,000 hours, and the process is compatible with mass production and is suitable for the fields of display, illumination and the like.

The invention provides a heterojunction quantum well and a preparation method thereof, and the method comprises the steps: providing a substrate, and forming a heterojunction quantum well at one side of the substrate through a chemical vapor deposition method; the heterojunction quantum well comprises a first barrier layer, a quantum well layer and a second barrier layer which are stacked in sequence, the first barrier layer is located between the quantum well layer and the substrate, the first barrier layer and the second barrier layer are both made of germanium-silicon, when the heterojunction quantum well is a silicon heterojunction quantum well, the quantum well layer is a silicon quantum well layer, and when the heterojunction quantum well is a silicon quantum well layer, the second barrier layer is a silicon quantum well layer. When the heterojunction quantum well is a germanium heterojunction quantum well, the quantum well layer is a germanium quantum well layer; in the process of forming the heterojunction quantum well, the precursor is decomposed in a target temperature range, and a product obtained through decomposition is deposited on one side of the substrate to obtain the heterojunction quantum well; the precursor is subjected to multi-stage reaction during decomposition, and the target temperature range is 300-550 DEG C; the interface quality of the heterojunction quantum well can be greatly improved, the surface roughness of the film layer can be reduced, and high-quality preparation of the heterojunction quantum well is realized.

The invention relates to the technical field of semiconductor photoelectrons, and discloses a vertical-cavity surface-emitting laser with an inverted structure and a preparation method of the vertical-cavity surface-emitting laser. The vertical cavity surface emitting laser with the inverted structure comprises a heterogeneous substrate, wherein a heat dissipation functional layer, a metal adhesion layer and a metal bonding layer are arranged on the surface of the heterogeneous substrate from bottom to top; the epitaxial structure comprises a p-type electrode, an ITO current expansion layer, a SiO2 current limiting layer, a first dielectric DBR layer, a p-type GaN layer, an electron blocking layer, a quantum well active region, an n-type GaN layer, a second dielectric DBR layer and an n-type electrode from bottom to top; and the p-type electrode is positioned at the bottom of the epitaxial structure and is bonded with the metal bonding layer to form an inverted structure. According to the vertical cavity surface emitting laser with the inverted structure provided by the invention, the heat dissipation function layer and the inverted structure design effectively improve the heat dissipation capability and the current uniformity of the device, and the service life, the performance stability and the reliability of the device are remarkably improved.

The invention relates to the technical field of semiconductor light-emitting devices, and particularly discloses an epitaxial structure for improving the internal quantum efficiency of a green Micro LED. The epitaxial structure comprises a substrate, and a buffer layer, an undoped GaN layer, an n-type GaN layer, a stress release layer, an active layer, a low-temperature Mg heavily-doped GaN layer, an electron barrier layer, a p-type GaN layer and a p-type GaN contact layer which are sequentially arranged on the substrate. The active layer comprises a plurality of periods of InGaN quantum well layers and an InAlGaN / GaN superlattice quantum barrier layer alternating structure, and a CAP layer formed by an AlGaN / GaN superlattice is arranged behind each quantum well layer. By adopting a wide-well narrow-barrier structure, a superlattice CAP layer for neutralizing a polarization electric field and a quaternary InAlGaN barrier structure for lattice matching and hole injection enhancement, multiple regulation and control of a polarization field, dislocation density and hole transport are realized, the internal quantum efficiency of a green-light Micro LED is remarkably improved, and the green-light Micro LED epitaxial structure is suitable for epitaxial preparation of a high-performance Micro LED chip.

The invention discloses a graphene integrated electrode LED epitaxial structure and a chip preparation method. The epitaxial structure sequentially comprises a GaAs substrate, an n-type GaAs buffer layer, an n-type limiting layer, a non-doped quantum well structure, a p-type spacer layer, a p-type electron barrier layer and a p-type GaP ohmic contact layer from bottom to top. The preparation method comprises the steps of epitaxial structure growth, p-type ITO transparent conductive layer preparation, bonding and substrate removal, mesa structure preparation, passivation isolation, graphene interconnection layer preparation and n-type electrode preparation. Graphene is used for replacing a traditional n-type GaAs ohmic contact layer and an ITO electrode, the problems of poor red light absorption, poor heat dissipation and mechanical brittleness of a traditional structure are solved, the red light transmittance of the chip is improved, the junction temperature under 3 currents is greatly reduced, the chip can bear tensile strain larger than 20%, the chip is suitable for flexible scenes, and the chip is suitable for high-performance large-scale production of red light Micro LEDs.

In order to provide an IR-QCL element which utilizes the characteristics of a ZnO-based semiconductor material, the present disclosure discloses a quantum cascade laser element 1000 that has a plurality of unit structures 10U in each of which a well layer of ZnO or ZnMgO and a barrier layer of ZnMgO or MgO are alternately and repeatedly stacked. Each unit structure includes a light emitting layer 10E and a continuum layer 10C. The light emitting layer includes: an upstream well layer 10W1 that is composed of a step quantum well having a first layer and a second layer, which have different MgO composition ratios from each other; and a downstream well layer 10W2 that has a smaller MgO composition ratio than any of the first layer and the second layer.

The invention belongs to the technical field of optical communication, and particularly relates to a narrow linewidth laser based on a cascaded micro-ring resonant cavity. The laser comprises a semiconductor laser inner cavity module, a gain chip module, a phase shifter, a cascade micro-ring resonant cavity module, a thermal tuning module and an outer cavity reflector. The gain chip is combined with an III-V group material at the top of the silicon waveguide through heterogeneous integration, and adopts an InAlGaAs quantum well to provide high gain; the phase shifter is used for matching the lasing wavelength with the resonant wavelength; the cascaded micro-ring resonant cavity is formed by cascading three micro-rings, and tuning of the laser is realized based on a vernier effect; the thermal tuning module is composed of three semi-annular metal strips and a straight waveguide-shaped metal strip. The outer cavity reflector module adopts a Sagnac ring structure; the laser inner cavity, the gain chip, the cascade micro-ring resonant cavity and the outer cavity reflector are directly connected through silicon waveguides. The laser has the characteristics of narrow linewidth and wide tuning range, is easy to highly integrate and interconnect, and has important application value.

The invention discloses a semiconductor laser and a preparation method thereof, which can be used in the field of semiconductor device preparation, and the method comprises the steps: firstly, providing a first conductive type substrate; then, epitaxially growing a buffer layer of a first conduction type, a lower optical waveguide limiting layer, a quantum well active light-emitting layer, an upper optical waveguide limiting layer, a corrosion barrier layer, a current injection layer and an intrinsic ohmic contact layer on the substrate in sequence to obtain a multi-layer epitaxial layer; then, etching the multi-layer epitaxial layer to the corrosion barrier layer based on a preset pattern to form a ridge-shaped table which starts from the intrinsic ohmic contact layer and is deeply cut off to the corrosion barrier layer; and finally, performing particle doping in a region corresponding to the ridge-shaped table, and converting one sides, close to the corrosion barrier layer, of the intrinsic ohmic contact layer, the current injection layer, the corrosion barrier layer and the upper optical waveguide limiting layer into a second conduction type. Therefore, current limitation can be realized without performing multiple epitaxy like a traditional buried heterojunction, and the production cost and the process difficulty are greatly reduced.

The invention discloses an AlGaInP red light LED chip structure with a polarization-induced tunnel junction and a preparation method thereof. The chip structure sequentially comprises a GaAs substrate, an n-type GaAs buffer layer, an n-type etching barrier layer, an n-type GaAs ohmic contact layer, an n-type limiting layer, a non-doped InGaP / quantum well structure, a p-type spacer layer, a p-type AlGaInP polarization-induced doping layer, an insertion layer and an n-type ohmic contact layer from bottom to top. Wherein the p-type AlGaInP polarization induction doping layer introduces a piezoelectric polarization electric field through an Al component gradual change design, high-density two-dimensional hole gas is formed through induction, and the high-Al component insertion layer and the n-type ohmic contact layer form a tunnel junction; according to the invention, the problems of low p-type doping efficiency and high resistivity of the AlGaInP material with high Al component are fundamentally solved, the epitaxial structure and the chip process are simplified, the series resistance of the chip is reduced, the luminous efficiency is improved, the yield is improved, and the method has remarkable technical and commercial values.

A device (1) for performing electrolysis of water is disclosed. The device comprising: a semiconductor structure (10) comprising a surface (11) and an electron guiding layer (12) below said surface (11), the electron guiding layer (12) of the semiconductor structure (10) being configured to guide electron movement in a plane parallel to the surface (11), the electron guiding layer (12) of the semiconductor structure (10) comprising an InGaN quantum well (14) or a heterojunction (18), the heterojunction (18) being a junction between AlN material and GaN material or between AlGaN material and GaN material; at least one metal cathode (20) arranged on the surface (11) of the semiconductor structure (10); and at least one photoanode (30) arranged on the surface (11) of the semiconductor structure (10), wherein the at least one photoanode (30) comprises a plurality of quantum dots (32) of InxGa(1-x)N material, wherein 0.4≤x≤1. Also a system comprising such device is disclosed.

The invention discloses an LED dimming system and method, and the system comprises a white light LED which is used for emitting a spectrum in a 400-650 nm wave band; at least three red light LEDs of blue light excitation fluorescent powder respectively emit red light with different central wavelengths, the central wavelength of the first red light LED is 660nm + / -2nm, the half-peak width is less than or equal to 15nm, and an I < n > GaA < l > P material vertical cavity surface emission structure is adopted; the central wavelength of the second red light LED is 730nm + / -3nm, the half-peak width is less than or equal to 20nm, and the second red light LED adopts an A < l > GaAs material quantum well structure; the center wavelength of the third red light LED is 780nm + / -5nm, the half-peak width is less than or equal to 25nm, and a GaAsP material gradient refractive index waveguide structure is adopted; the driving control module comprises three independent constant-current driving units which are used for respectively controlling the current and PWM duty ratio of each red light LED; the optical mixing module is composed of a two-stage integral rod and a micro lens array and is used for realizing uniform mixing of spectrums.

The invention provides a buried heterojunction structure, a preparation method thereof and a laser. The preparation method comprises the following steps: primary epitaxy: growing an N-type InP buffer layer, a multi-layer quantum well structure and a P-type InP protective layer on an N-type InP substrate by using an MOCVD (Metal Organic Chemical Vapor Deposition) technology; growing an etching stop layer on the P-type InP protection layer, wherein the etching stop layer is made of an III-V group material; depositing an insulating medium as a mask on the etching stop layer, and etching the etching stop layer and the basic structure layer in a dry or wet etching mode to form a mesa structure; removing the mask on the mesa structure by wet etching; secondary epitaxy: growing a current limiting layer on the mesa structure by adopting an MOCVD (Metal Organic Chemical Vapor Deposition) technology, wherein the current limiting layer covers the whole mesa structure; and forming a funnel-shaped opening on the current limiting layer by wet etching to expose the etching stop layer. According to the invention, the difficulty of growing the current limiting layer by using the MOCVD technology is greatly reduced; the problem of current leakage is effectively suppressed; the current injection efficiency is improved; and the method has good process repeatability and controllability.

According to the deep ultraviolet laser epitaxial structure and the epitaxial growth method thereof provided by the invention, the Al component of the first waveguide layer is linearly and progressively increased from the side close to the electron injection layer to the side close to the quantum well active layer; or the Al component of the second waveguide layer is linearly and progressively decreased from the side close to the quantum well active layer to the side close to the hole injection layer to form refractive index distribution which takes the barrier layer of the quantum well active layer as the highest refractive index point and gradually decreases towards one side (the n-type side or the p-type side), so that the light field is firmly bound near the quantum well active layer, and the light limiting capability is remarkably enhanced; meanwhile, high-low Al components of the p-type side (the second waveguide layer) gradually change to generate a strong polarization electric field, ionization of a p-type doped acceptor (such as Mg) can be promoted, two-dimensional hole gas (2DHG) can be induced, and the hole concentration is improved; the low-high Al components of the n-type side (the first waveguide layer) are gradually changed, so that two-dimensional electron gas can be induced, and the electron concentration is improved.

The invention discloses a preparation method and a structure of a novel electro-absorption modulated laser, and the method comprises the steps: symmetrically dividing a substrate into a double-end modulation region, a gain region, a grating region and a phase region, manufacturing a first mask pattern on the surface of the gain region, growing an active layer containing a quantum well structure in a mask gap through a selective region epitaxy technology, forbidden band red shift of the gain region is realized; manufacturing a mask covering the gain region and the modulation region, and etching a non-functional region to expose the substrate; a passive material with a wider band gap is grown in the exposed substrate area in a butt joint mode, and a photon limiting structure is formed; manufacturing a sampling grating through electron beam direct writing, growing a cladding layer and a contact layer, and etching an inverted table shallow ridge waveguide; and finally, etching an electrical isolation trench and manufacturing a double-sided electrode to complete device integration. Through the selective area epitaxial growth technology, active materials with two forbidden bandwidths of the gain area and the modulation area are achieved through one-time epitaxial growth, and a solution with extremely low cost is provided for the wavelength tunable electro-absorption modulated laser.

The invention relates to an anti-radiation five-junction solar cell and a preparation method thereof, and belongs to the technical field of semiconductor devices. The radiation-proof five-junction solar cell comprises a substrate, and a first buffer layer, a first component order change buffer layer, a fourth sub-cell, a second component order change buffer layer, a fourth tunnel junction, a fifth sub-cell and an electrode contact layer which are sequentially stacked on a first surface of the substrate, a second buffer layer, a third tunnel junction, a third sub-cell, a second tunnel junction, a second sub-cell, a first tunnel junction, a first sub-cell and a cap layer are sequentially stacked on the second surface of the substrate; and the base region thicknesses of the second sub-cell, the third sub-cell and the fourth sub-cell are smaller than the respective emitter region thicknesses. The anti-radiation five-junction solar cell comprises a plurality of sub-cells with quantum well structures, so that the anti-radiation performance of the solar cell can be effectively improved, and the last-stage use efficiency of the solar cell is further remarkably improved.

The invention provides an epitaxial structure of a semiconductor laser and a preparation method thereof. The epitaxial structure comprises a first waveguide layer, a first barrier layer, a first barrier layer, a quantum well layer, a second barrier layer, a second barrier layer and a second waveguide layer which are stacked from bottom to top. By adjusting different contents of an aluminum element and a gallium element in the first waveguide layer, the first barrier layer, the second barrier layer and the second waveguide layer, adjusting different contents of a gallium element and an indium element in the first barrier layer, and adjusting different contents of an aluminum element, a gallium element and an indium element in the second barrier layer, a first conduction band difference delta Ec11 is greater than 70meV, a second valence band difference delta Ev21 is greater than 240meV, and a second valence band difference delta Ev21 is greater than 240meV. The first valence band difference delta Ev11 and the second conduction band difference delta Ec21 are both smaller than or equal to 0 meV. The epitaxial structure can well balance the limiting effect on electrons and holes, so that the limiting capability of the epitaxial structure on current carriers is optimal, and the output efficiency of the device is improved.

The invention provides a high-stability single-mode semiconductor laser based on dynamic wavefront shaping and a control system, and relates to the technical field of semiconductor lasers, comprising a semiconductor laser gain module, a dynamic wavefront shaping module, a single-mode screening module and a laser output module which are optically coupled in sequence, wherein the semiconductor laser gain module is composed of a quantum well structure gain chip, a distributed feedback grating and a surface plasma structure are integrated on the surface of an active area of the gain chip, and the distributed feedback grating and the surface plasma structure are combined on the surface of the active area through a surface etching process. According to the invention, through the dynamic wavefront shaping module and the multi-parameter closed-loop control system, real-time adaptive regulation and control of the whole laser output process are realized. According to the system, wavefront distortion can be rapidly detected and compensated in a complex disturbance environment, and response delay and manual intervention of traditional static correction are remarkably reduced.

A laser diode includes an active region, confinement layers, and cladding layers. The active region includes one or more active layers that each exert a first strain in a first direction and one or more strain compensating layer that each exert a second strain in a second direction that is opposite the first direction. The confinement layers bound the active region. The cladding layers bound the confinement layers. In some embodiments, each active layer comprises InAs quantum dots in a InrGa1-rAs quantum well, where 0≤r≤1; and each strain compensating layer comprises a GaAs1-sPs layer, where 0<s≤1. The confinement layers may each comprise a (AlzGa1-z)wIn1-wP layer, where 0<w<1 and 0≤z<1. The cladding layers may each comprise a (AlyGa1-y)xIn1-xP layer, where 0<x<1 and 0≤y<1.

The invention relates to the technical field of semiconductors, and discloses a GaAs-based vertical-cavity surface-emitting laser with a small-size mesa structure and a preparation method thereof.The laser comprises an n-surface electrode layer, a substrate layer, a buffer layer and an n-DBR layer which are sequentially arranged from bottom to top, and an insulating layer located on the periphery is arranged above the n-DBR layer; a lower space layer, a quantum well active region, an upper space layer, a p-oxidation limiting structure layer, a p-DBR layer, a contact layer and a p-surface electrode layer which form a cylindrical mesa are sequentially arranged at the center of the insulating layer from bottom to top; the p-oxidation limiting structure layer comprises a low-refractive-index layer, an oxidation limiting layer and a high-refractive-index layer which are sequentially arranged from bottom to top, an aluminum oxide layer is formed on the periphery of the oxidation limiting layer through an oxidation process, an oxidation hole is formed in an unoxidized area in the center of the oxidation limiting layer, and the difference between the diameter of the cylindrical table board and the diameter of the oxidation hole is smaller than or equal to 15 microns. According to the invention, the threshold current can be reduced and the luminous power can be improved.

The invention relates to a terahertz near-field imaging light path calibration device and a terahertz near-field imaging light path calibration method. The device comprises a first visible light source, a second visible light source, a first collimation visible light source, a second collimation visible light source, a first light path collimation system, a second light path collimation system, a light path adjusting system, a circular reflector, a terahertz quantum cascade laser, a thermal detection array, a terahertz quantum well detector and an atomic force microscope platform. The THz laser source and the detector are simulated through the divergent visible light source, the lifting position point of the light path is calculated, light beams can be accurately coupled to the position of the needle point after being focused, errors caused by improper light path adjustment are reduced, meanwhile, the overlapping effect of light spots at the needle point is calibrated through the circular reflector and the thermal detection array, and the detection accuracy is improved. And the thermal detection array is used for observing the convergence effect of THz reflection light spots at the position of the detector, so that the effective focusing and coupling efficiency of THz waves in a near-field region of a probe sample can be improved.

The embodiment of the invention provides an optical module and an optical modulator. A hybrid integrated optical chip comprises the optical modulator, a wave separator and a wave combiner. The optical modulator comprises a silicon waveguide layer, an N-type InP layer, a quantum well layer and a P-type InP layer from bottom to top. The gradual change structures are formed at the two ends of the optical modulator respectively, and the silicon waveguide and the InP region waveguide at the same end have opposite gradual change trends, so that mode mutation when light is coupled between the silicon waveguide and the InP waveguide is reduced, and low-loss coupling of the light between the silicon waveguide and the InP waveguide is achieved. In a coupling region at one end of the light modulator, the width of the silicon waveguide is gradually narrowed, and the width of each layer of waveguide in the InP region is gradually widened, so that more light field energy to be modulated is upwards coupled to the InP region for modulation. And in a coupling region at the other end of the optical modulator, the width of the silicon waveguide is gradually increased, and the width of each layer of waveguide in the InP region is gradually reduced, so that more modulation light field energy is downwards coupled into the silicon ridge waveguide to be output.

The invention is suitable for the technical field of semiconductor LED display, and provides a high-color-gamut LED chip structure and a preparation method thereof. The high-color-gamut LED chip structure comprises a substrate material, a buffer layer, a first semiconductor layer, a green wave quantum well layer, an electron hole adjusting layer, a blue wave quantum well layer, a second semiconductor layer, a current blocking layer and a current expansion layer which are sequentially arranged from bottom to top, and further comprises a first metal electrode layer, a second metal electrode layer and a transparent insulating layer. The electron hole adjusting layer is used for controlling the distribution of electrons and holes in the green wave quantum well layer and the blue wave quantum well layer so as to adjust the wavelength and the spectral intensity of emergent light of the green wave quantum well layer; through introduction of the electron hole adjusting layer, the wavelength of a long wave and the corresponding spectral intensity can be effectively controlled, two wavelengths can be emitted from a single chip, and through introduction of double waves, the color gamut of a display screen can be improved.

The invention provides a vertical deep ultraviolet LED epitaxial structure and a preparation method thereof. The vertical deep ultraviolet LED epitaxial structure comprises a substrate, an intrinsic layer, a sacrificial layer, a first electron injection layer, an etching barrier layer, a second electron injection layer, a quantum well active layer, an electron barrier layer and a hole injection layer which are sequentially stacked from bottom to top. Wherein the etching barrier layer is made of an n-type doped AlGaN material or an n-type doped AlN material; the mass percentage content of an Al component of the etching barrier layer is 70%-100%; according to the invention, the etching barrier layer with a high Al component is inserted into the electron injection structure, and the high Al-N bond energy and strong chemical stability of the etching barrier layer are utilized, so that the subsequent epitaxial layer can be effectively prevented from being excessively corroded in the dry etching process of the sacrificial layer, and the interface damage is reduced; meanwhile, the etching barrier layer with the high Al component and the electron injection layer form a remarkable barrier difference, the high barrier can guide electrons to be transversely and uniformly diffused in the electron injection layer, and the current density uniformity of the quantum well active layer is improved.

The invention relates to the technical field of semiconductor manufacturing, in particular to a light-emitting diode and a light-emitting device. The light-emitting diode at least comprises an epitaxial laminated layer; the epitaxial laminated layer comprises an N-type semiconductor layer, an active layer and a P-type semiconductor layer which are laminated in sequence; the active layer comprises at least one first-class quantum well layer and at least one second-class quantum well layer, the In concentration of the first-class quantum well layer is larger than that of the second-class quantum well layer, and the first-class quantum well layer is not in direct contact with the surface of the N-type semiconductor layer. According to the light-emitting diode provided by the invention, through the position design of the first type of quantum well layer, the influence of the quantum limited stark effect on the first type of quantum well layer with relatively high In concentration can be effectively relieved, the regulation and control of the carrier injection level are improved, the luminous intensity proportion is effectively adjusted, and the color rendering property of a device is improved.

The invention discloses a three-dimensional asymmetric photonic crystal laser and a preparation method thereof. An epitaxial structure of the three-dimensional asymmetric photonic crystal laser comprises an N-type electrode, an N-type InP substrate, an N-type Al < x > < 1 > In < 1-x > < 1 > As upper limiting layer, a quantum well active region, a P-type Al < y > < 1 > In < 1-y > < 1 > As electron barrier layer, a P-type Ga < z > < 1 > In < 1-z > < 1 > Asz < 2 > P < 1-z > 2 functional layer, a P-type Al < x > < 2 > In < 1-x > < 2 > As lower limiting layer, a P-type InP connecting layer, a bottom insulating layer and a P-type electrode, wherein a three-dimensional asymmetric photonic crystal is etched on the P-type GaInAsP functional layer, and a chiral characteristic is introduced by destroying the symmetry of the photonic crystal, so that the P-type GaInAsP functional layer vertically emits a single-mode light beam with left-handed or right-handed circular polarization. By designing an asymmetric photonic crystal structure, efficient output of circularly polarized light beams is achieved, polarization selectivity and light beam quality are remarkably improved, and the advantages of low divergence angle and high light beam stability are achieved.

The utility model relates to the technical field of semiconductor photoelectronics, and provides a white light package adopting a blue-green double-peak single crystal chip, which comprises a package structure and an LED chip arranged in the package structure. The LED chip comprises a substrate, a blue-green double-peak single crystal chip and a red light conversion layer which are sequentially stacked from bottom to top, the blue-green double-peak single crystal chip comprises an electroluminescent blue light quantum well layer and a photoluminescent green light conversion layer, and the red light conversion layer comprises a red light wavelength conversion material containing perovskite quantum dots. A red light wavelength conversion material containing perovskite quantum dots is arranged in the red light conversion layer, the light absorption coefficient of the perovskite material is 105cm <-1 > magnitude, a backlight source with an extremely high display color gamut can be obtained, the color gamut can reach more than 100% of NTSC, the color gamut is far larger than the color gamut which can be achieved by a traditional red light fluorescent powder layer, and the display color gamut of the LED chip is further improved.