30results about How to "Improved current scaling performance" patented technology

The invention provides a strained superlattice tunnel junction ultraviolet LED (light emitting diode) epitaxial structure and a production method thereof. The epitaxial structure from top to bottom comprises: an epitaxial growth substrate, an AlN buffer layer, an n-type AlGaN layer, a multiple quantum wells, an electron blocking layer, a strained superlattice, an n-type degenerate doped AlGaN layer, and an n-type Si-doped AlGaN layer. The strained superlattice comprises a p-type AlGaN layer and an AlyGa1-yN / AlxGa1-xN. An AlGaN energy band, under effects of a polarized electric field, moves as a whole along a low energy direction. A superlattice structure contacts a heavily doped n-type AlGaN to form a p-AlGaN / SSL / n *-AlGaN tunnel junction. Electrons of a p-type AlGaN valence band, under effects of an external electric field, carried out tunneling through a tunnel effect to one side of the n-type AlGaN, and a hole is formed in the p-type AlGaN. The n-AlGaN is used as the cladding material instead of the p-type AlGaN, so that the problem of the p-type ohmic contact is avoided.

The invention discloses an LED chip and a preparation method thereof, and belongs to the technical field of semiconductors. The LED chip comprises a substrate, an undoped AlN buffer layer, an undoped GaN layer, an N-type GaN layer, a multi-quantum well layer, a P-type Al<y>Ga<1-y>N layer, a P-type GaN layer and a graphene film layer, wherein the undoped AlN buffer layer, the undoped GaN layer, the N-type GaN layer, the multi-quantum well layer, the P-type Al<y>Ga<1-y>N layer, the P-type GaN layer and the graphene film layer are sequentially stacked on the substrate; y is smaller than 0.5 and greater than 0.1; the multi-quantum well layer comprises an InGaN layer and a GaN layer which are alternately stacked; a groove which extends to the N-type GaN layer is formed in the graphene film layer; an N-type electrode is arranged on the N-type GaN layer; a P-type electrode is arranged on the graphene film layer; and multiple TiO2 nanorods are arranged on the graphene film layer in an array manner. The graphene film layer can be directly adopted as a seed layer through formation of the TiO2 nanorods, and the seed layer is tightly combined and is not easily destroyed, so that the light-emitting efficiency of an LED can be obviously improved.

The invention relates to an avalanche commutation diode special for a 16000A / 200-400V welding machine and a preparation method thereof. The invention solves the problems that an avalanche commutation diode special for a single welding machine has small capacity and that parallel connection and flow equalization are needed during the use of the avalanche commutation diode. An N-type (100) radial single crystal silicon piece, which has specific resistance Rho n of 5-10 Ohm-cm, diameter of 70 mm and thickness of 0.17-0.19 mm, is adopted; at the temperature of 1250 DEG C, double-surface once diffusion is carried out; the surface concentration of a surface higher-concentration region of a diffusion region is 0.06-n A, a junction depth X jP is 58-62 microns, and residual minority carrier lifetime Tao p of a base region is 9-13 Mu S; cathode-anode titanium-nickel-gold undergoes ohmic contact; a cathode table surface undergoes spray sand molding, corrosion, cleaning, passivation protection andintermediate test; and a shell is arranged, the thickness of a pipe is 5-6 mm, cold pressure welding packaging is conducted under the protection of nitrogen gas, and the thickness of the pipe is 5-6mm after the packaging. The avalanche commutation diode has stronger current expansion capability, larger capacity, better quality, higher reliability and lower use cost.

The invention provides a diode structure design with uniform luminous intensity. An epitaxial wafer structure comprises a substrate, an N-type layer, a multi-quantum well active region and a P-type layer from bottom to top; preparation of a chip technology is carried out; a current adjusting structure is arranged at the position, close to an N electrode, in the N-type layer; a resistance value of a region at the position, close to the N electrode, in the N-type layer is increased by the current adjusting structure; the current carrier aggregation effect of the position close to the N electrode is reduced by controlling the summarized occupied volume and the transverse and longitudinal etching depths of the current adjusting structure in the N-type layer; relatively multiple current carriers flow to the position close to a P electrode; the number of electrons which flow to the position close to the P electrode in the N-type layer is increased; different positions of a same LED chip are relatively uniform in light-emitting; and meanwhile, the current carrier aggregation effect is relieved, so that the reliability of an LED is further improved.

The utility model discloses a light emitting diode chip and a preparation method thereof, and belongs to the technical field of semiconductors. The preparation method includes that an epitaxial wafer of the light emitting diode chip is provided, a transparent conducting layer, a first electrode and a second electrode are arranged on the epitaxial wafer, the second electrode is arranged on the transparent conducting layer, a metal layer is arranged on the transparent conducting layer in a depositing mode, photoresist is evenly coated on the metal layer, a root hair matrix of the photoresist can be manufactured by using of photoetching technique, and the root hair matrix is in a long strip shape and extend from the second electrode. A layer of silicide is coated on the metal layer which is provided with the root hair matrix in a depositing mode. Silicide except silicide on the side face of the root hair matrix is removed by using dry etching. The dry etching is removed by using organic solvent so that silicide root hairs are obtained. The silicide root hairs are formed by the silicide on two sides of the root hair matrix and used as covering films to etch the metal layer and removed after etching is finished, so that current expanding root hairs are obtained. Through the scheme, current expanding capacity is improved.

The present invention discloses a manufacture method of a light emitting diode having a high extension effect. The manufacture method comprises the following steps: providing an epitaxial substrate; growing the epitaxial layer of the light emitting diode through adoption of MOCVD; forming protection glue at the surface of the epitaxial layer of the light emitting diode, and performing alternate vacuum evaporation of a plurality of layers of Ni-Fe alloy membranes and Si3N4 membranes at two of four side faces of the epitaxial layer of the light emitting diode; performing alternate vacuum evaporation of a plurality of layers of Si3N4 membranes and Ni-Fe alloy membranes at the other two of four side faces of the epitaxial layer of the light emitting diode; and removing the protection glue at the surface of the epitaxial layer of the light emitting diode, exposing a p electrode and a n electrode, and forming an independent light emitting diode device through separation of epitaxial wafers. According to the invention, N-type and P-type current expansion of a light emitting diode is effectively enhanced without increasing the light blocking area of electrodes, and the N-type current expansion effect of a large-size chip is improved.

The invention discloses a large-power vertical structure LED epitaxial structure. The large-power vertical structure LED epitaxial structure includes a pre-paved Al layer, an AlN buffer layer, an AlGaN buffer layer, a u-type GaN layer, a first graphene layer, an n-type GaN layer, a multi-quantum well, a p-type GaN layer, and a second graphene layer, wherein all the above layers and the multi-quantum well are grown on an Si substrate; and the first graphene layer and the second graphene layer are formed by vapor deposition. The large-power vertical structure LED epitaxial structure has better photoelectric performance and has wide application.

The invention relates to a fast-recovery commutation diode used for high frequency electroplating and a production method thereof, wherein the fast-recovery commutation diode has the high frequency property and is suitable for 30KHz / 2-5KA / (200-400)V high frequency electroplating with both high voltage and high current density. An N-type (100) radial single crystal silicon piece, which has specificresistance Rho n of 5-9 Ohm-cm, diameter of 48-70 mm and thickness of 175-185 microns, is adopted; silicon piece diffusion is conducted, and double-surface once diffusion is carried out at temperature of 1250 DEG C; the diffusion piece detection is carried out; phosphorosilicate glass and borosilicate glass are used for absorption, the temperature is slowly lowered from 1250 DEG C to 1050 DEG C,the speed rate is 1 DEG C per minute, and isothermal absorption is carried out for 2-3 h; slow temperature reduction is continued till furnace temperature is reduced to 600 DEG C, then furnace delivery is carried out, and minority carrier lifetime Tao p is caused to reach 12-16 Mu S; platinum diffusion is carried out at low temperature so that the minority carrier lifetime Tao p is controlled to be 4-6 Mu S; 12 Mev electron irradiation is carried out so that the minority carrier lifetime Tao p of a base region is 0.9-1.1 Mu S; the two surfaces of the silicon piece are plated with titanium-nickel-gold by means of vapor deposition and then undergo table-board spray sand molding, desanding, cleaning, corrosion, passivation protection, intermediate test, shell arrangement and packaging, and after tests testify qualification, the finished product is produced.

The invention provides a high-power ultraviolet light emitting diode and a manufacturing method thereof. Firstly, N-type through holes are arranged to electrically connect a conductive layer with a first conductive layer, which improves the current expansion capability of the ultraviolet light emitting diode. Secondly, uniformly-distributed expanded through-holes are formed in a transparent conductive layer to make the transparent conductive layer, a metal mirror and a second conductive layer form ohmic contact. The N-type through holes and the extended through holes are arranged in a staggered manner along the vertical direction of the transparent conductive layer. The number of the N-type through holes is reduced while the effect of current expansion is guaranteed, and the area loss of the active layer caused by too many through holes is avoided.

The invention discloses a Mini LED chip and a manufacturing method, comprising a GaN substrate, a P-type contact surface and a current stabilization layer, a P-type current injection layer, a P-type welding interface metal layer, a buffer insulating layer, a stress Release layer, insulating full-spectrum reflective layer, N-type welding interface metal layer, N-type current injection layer, N-type contact surface and current stabilization layer; the present invention uses P-type contact surface and current stabilization layer, P-type current injection layer, The use of special functional layers such as buffer insulation layer, stress release layer, N-type current injection layer, N-type contact surface and current stabilization layer solves the problems of current resistance, insulation layer stress, insulation layer adhesion and pad and The problem of the adhesion of the solder paste makes the Mini LED chip have excellent reliability and various performances, and at the same time, it can ensure the production efficiency and production yield of the Mini LED chip.

The invention relates to an MIS structured ultraviolet LED based on local surface plasmon enhancement and a preparation method thereof. According to the invention, silver metal nanoparticles are introduced into the MIS structured ultraviolet LED to form a local surface plasmon; the MIS structured LED adopts a graphene film to serve as a conductive layer so as to enhance the current expansibility and improve the ultraviolet light emitting rate of the device; and the metal nanoparticles are arranged on the graphene layer, and emitted photons are enabled to have resonance coupling with the metalnanoparticles by using the local surface plasmon enhancement effect, so that the internal quantum efficiency of the device is improved, and the light emitting intensity of the device is enhanced. TheMIS structured ultraviolet LED based on the local surface plasmon enhancement provided by the invention has the advantages of simple structure, simple and convenient preparation and easy production.

The invention discloses a light-emitting diode and a manufacturing method thereof. Firstly, a first scribe line with a first line width is etched on an epitaxial wafer, and then a second scribe line with a second line width is etched at the first scribe line. The width is smaller than the first line width, thereby reducing the area to be removed by etching the P-type GaP current spreading layer, and improving the current spreading ability; When the ablation groove of the third line width is laser ablated at the track, the melt produced by the ablation of the laser on the P-type GaP current spreading layer is reduced, thereby reducing the absorption loss of the melt on the light emitted by the light-emitting diode, and improving the efficiency of the light-emitting diode. luminous efficiency. And, roughen the exposed surface of the P-type GaP current spreading layer away from the substrate and its sidewall, thereby reducing the total reflection phenomenon in this region and increasing the edge luminous efficiency.