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64results about How to "Improve concentration distribution" patented technology

Charge storage-type insulated gate bipolar transistor with trench gate and manufacturing method of charge storage-type insulated gate bipolar transistor

The invention discloses a charge storage-type insulated gate bipolar transistor with a trench gate and a manufacturing method of the charge storage-type insulated gate bipolar transistor and belongs to the field of semiconductor power devices. A trench emitter structure is introduced into an N-type drift region of a traditional CSTBT structure, a P-type layer and a series diode structure are sequentially introduced to the lower part and the surface of the trench emitter structure, and meanwhile, the insulated gate bipolar transistor has a trench gate structure which partially penetrates into an N-type charge storage layer along the vertical direction, so that the problem of a contradictory relationship between the positive conduction performance and the voltage resistance of a device due to improvement of the doping concentration of the N-type charge storage layer in the traditional CSTBT is solved through the improvement; the saturation current density of the device is reduced and a short-circuit safety operation area of the device is improved; the switching speed of the device is improved and the switching loss is reduced; the breakdown voltage of the device is improved and the reliability is improved; compromise between a positive conduction voltage drop and the turn-off loss is optimized; and meanwhile, the manufacturing method of the device is compatible with a manufacturing technology of an existing CSTBT device.
Owner:UNIV OF ELECTRONIC SCI & TECH OF CHINA

Trench gate charge storage type insulated gate bipolar transistor and manufacturing method therefor

The invention discloses a trench gate charge storage type insulated gate bipolar transistor and a manufacturing method therefor, and belongs to the technical field of a semiconductor power device. Byovercoming the adverse influence of an N type charge storage layer in the conventional structure, more excellent voltage withstand performance is obtained; and compared with the conventional mode, thecompromising characteristic among the switching performance, switch-on voltage drop and switching loss of the device is realized by increasing the trench gate depth and reducing cellular width, and the problem of reliability degradation is solved. By introducing a series diode structure into a P type body region, the channel voltage of an MOSFET is clamped at a quite small value, thereby loweringdevice saturated current density and improving the short-circuit safety working region of the device; by introducing a split electrode and a split electrode dielectric layer to the trench gate structure, the threshold voltage and switching speed of the device are ensured while the switching performance of the device is improved; and by virtue of the floating P type body region, the compromising characteristic between the forward switch-on voltage drop and switching loss of the device is improved. In addition, the manufacturing process of the CSTBT device is compatible with the conventional manufacturing process.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA

Method for improving denitration rate of SCR (Selective Catalytic Reduction) denitration system of power station boiler

The invention discloses a method for improving the denitration rate of an SCR (Selective Catalytic Reduction) denitration system of a power station boiler. The method comprises the following steps: (1) measuring concentration distribution of NOx at the outlet of an SCR denitration reactor; (2) calculating the unevenness Cv of concentration distribution of NOx according to the measuring result in the step (1); (3) when Cv is greater than 20%, adjusting the valve opening in an area corresponding to an ammonia injection grid according to the concentration distribution of NOx at the outlet of the SCR denitration reactor; (4) repeating the steps (1) to (3) until Cv is less than or equal to 20%. Through optimization and adjustment by the invention, the evenness of distribution of NOx at the outlet of the SCR denitration reactor is remarkably improved, and the relative standard deviation of NOx is reduced from 46.4% to 14.8%. On the premise of ensuring that ammonia escape does not exceed standard, the denitration rate is improved from 77% to 83%. The method disclosed by the invention has important guiding meaning and engineering application value to safe, efficient and stable operation of the SCR denitration system of the power station boiler.
Owner:ELECTRIC POWER RES INST OF GUANGDONG POWER GRID

Reverse blocking type IGBT and manufacturing method therefor

The invention discloses a reverse blocking type IGBT and a manufacturing method therefor, and belongs to the technical field of a power semiconductor device. By introducing a floating P type body region on one side of a trench gate and introducing a trench collector structure in a collector region and a field stop layer, the positive breakdown voltage of a device is improved without influencing the threshold voltage and switch-on of an IGBT device; the gate-collector capacitance is lowered, and adverse influence caused by a Miller effect can be relieved; the overall gate capacitance is lowered, the switching speed of the device is improved, the switching loss of the device is lowered, and the compromising relation between forward switch-on voltage drop and switch-off loss of the conventional CSTBT device is improved; the problems of current, voltage oscillation and EMI in the device starting dynamic process can be avoided, and device reliability is improved; the current carrier enhancement effect at the emitter end of the device is improved, the current carrier concentration distribution in a drift region can be improved, and compromising between forward switch-on voltage drop andswitch-off loss can be further improved; and the reverse breakdown voltage of the device is improved, and high forward characteristic of the device is ensured while excellent reverse blocking performance is obtained.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA

Trench-gate charge storage type IGBT and manufacturing method therefor

The invention discloses a trench-gate charge storage type IGBT and a manufacturing method therefor, and belongs to the technical field of semiconductor power devices. A trench-gate emitter structure connected with a P-type volume region is introduced to an N-type drift region at one side of a trench gate in a conventional CSTBT device, thereby enabling the gate-collector capacitance into gate-emitter capacitance, and improving the adverse effect of Miller capacitance. A thick dielectric layer of the trench-gate emitter structure avoids an electric field concentration effect at the bottom of atrench, and improves the breakdown voltage of a device. The depth of a gate electrode is enabled to be less than the junction depth of an N-type charge storage layer, thereby reducing the overall gatecapacitance under the condition that the connection of an IGBT is not affected, improving the switching speed of the device, reducing the switching loss of the device, and improving the compromise characteristics between a positive conduction voltage and the switching-off loss. According to the invention, the existing of the P-type volume region can reduce the extraction area of a hole, and improves the carrier concentration distribution of the whole N-type drift region. Moreover, the noise impact is reduced, and the EMI effect is avoided.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA

Semiconductor process equipment and mixed gas inlet device thereof

The embodiment of the invention provides semiconductor process equipment and a mixed gas inlet device thereof. The mixed gas inlet device comprises a mixed gas inlet block and a cover body assembly; a first annular cavity and multiple gas inlet channels are formed in the mixed gas inlet block, the top of the first annular cavity communicates with the multiple gas inlet channels, and the bottom of the first annular cavity communicates with a gas mixing channel in the cover body assembly; the multiple gas inlet channels extend in the tangential direction of the first annular cavity, and gas outlets of the multiple gas inlet channels are evenly distributed in the circumferential direction of the first annular cavity; and the mixed gas inlet block is arranged in the middle of the top of the cover body assembly, the bottom of the cover body assembly covers the top of a process chamber, and the gas mixing channel is formed in the cover body assembly and used for re-mixing process gas in the mixed gas inlet block and inputting the process gas into the process chamber after uniform flow. According to the embodiment of the invention, the concentration distribution of the process gas is effectively improved before the process gas reaches the surface of a wafer so that the film forming uniformity of the wafer can be greatly improved while the process time is effectively shortened.
Owner:BEIJING NAURA MICROELECTRONICS EQUIP CO LTD

Percutaneously absorbable preparation

InactiveUS20100010043A1Favorable plasma drug concentration profileImprove concentration distributionBiocideNervous disorderPercutaneous absorptionKetone
The present invention provides a percutaneously absorbable preparation comprising 2-[(1-benzylpiperidin-4-yl)methyl]-5,6-dimethoxyindan-1-one and / or a hydrochloride thereof wherein the percuneously absorbable preoaration is able to administer to a patient such that Cmax per unit surface area of the percutaneously absorbable preparation is 0.025 to 0.5 ng / ml·cm2 in a plasma concentration profile.
Owner:EISIA R&D MANAGEMENT CO LTD +1

Plane gate IGBT and manufacturing method therefor

The invention belongs to the technical field of a power semiconductor device, and relates to a plane gate IGBT and a manufacturing method therefor. On the basis of the conventional plane gate IGBT device structure, a surface recombination device structure is introduced, so that the gate electrode capacitance, particularly the gate electrode-collector electrode capacitance of the device is reduced, the switching speed of the device is improved, and the switching loss of the device is lowered; and meanwhile, the forward conduction voltage drop and the drift region carrier concentration distribution of the device are improved, the performance of the device is enhanced, and degradation of the blocking performance of the device is prevented.
Owner:UNIV OF ELECTRONIC SCI & TECH OF CHINA

Trench gate charge storage type IGBT and manufacturing method thereof

The invention discloses a trench gate charge storage type IGBT, and belongs to the technical field of semiconductor power devices. A conventional trench gate structure is widened, and a side wall gateelectrode structure is employed for forming a mesa structure located below a base region. moreover, a shielding trench structure for shielding the electric field of a charge storage layer is introduced, thereby improving the carrier injection enhancement effect, and improving the compromise between a forwarding ON voltage drop Vceon and the OFF loss Eoff. The electric field concentration effect at the tip of the bottom of a trench is alleviated, and the breakdown voltage of a device is effectively improved. The gate capacitance of the device, especially the Miller capacitance CGC and the gatecharge QG, is reduced, the switching speed of the device is improved, the switching loss of the device is reduced, and the requirements for the capability of a gate drive circuit are reduced. The constraint on the doping concentration of an N-type charge storage layer and the withstand voltage of the device from the thickness are avoided, the saturation current density is reduced, and a short-circuit safe operating region (SCSOA) of the device is improved. Moreover, an EMI effect is effectively inhibited when the device is turned on. In addition, the manufacturing method is compatible with aconventional trench gate charge storage type IGBT manufacturing method.
Owner:UNIV OF ELECTRONIC SCI & TECH OF CHINA

Bi-directional trench gate charge storage type IGBT (insulated-gate bipolar transistor) and manufacturing method thereof

The invention provides a bi-directional trench gate charge storage type IGBT (insulated-gate bipolar transistor) and belongs to the technical field of a semiconductor power device. By means of widening of a traditional trench gate structure, formation of a mesa structure below a base region by a side wall gate electrode structure as well as introduction of a shielding trench structure, carrier injection enhancement effect is increased while symmetric forward / reverse conduction and turn-off characteristics of the device are realized, and compromise between forward voltage drop Vceon and turn-off loss Eoff is improved; electric field concentration effect at a sharp corner of the bottom of a trench is reduced, and breakdown voltage of the device is effectively increased; gate capacitance of the device is reduced, so that switching speed of the device is increased, switching loss of the device is reduced, and the requirement for capacity of a gate driven circuit is reduced; limitation of doping concentration and thickness of an N-type charge storage layer to device withstand voltage is avoided; saturation current density is reduced, and a short circuit safe operating area of the deviceis improved; further, EMI (electro-magnetic interference) effect produced when the device is conducted is effectively inhibited. Besides, a manufacturing method is compatible with a traditional CSTBTmanufacturing method.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA

Reverse blocking type IGBT and manufacturing method therefor

The invention discloses a reverse blocking type IGBT and a manufacturing method therefor, and belongs to the technical field of a semiconductor power device. By introducing trench emitter and trench collector structures, the reverse breakdown voltage of a device is improved without influencing the threshold voltage and switch-on of an IGBT device; the overall gate capacitance is lowered, the switching speed of the device is improved, the switching loss and driving power consumption of the device are lowered, and the compromising relation between forward switch-on voltage drop and switch-off loss of the conventional CSTBT structure is improved; the problems of current, voltage oscillation and EMI in the device starting dynamic process can be avoided, and device reliability is improved; theelectric field concentration effect at the bottom of the trench is improved, the forward breakdown voltage of the device is improved, and reliability of the device is further improved; and the currentcarrier enhancement effect at the emitter end of the device is further improved, the current carrier concentration distribution in a drift region can be improved, and compromising between forward switch-on voltage drop and switch-off loss can be further improved. The manufacturing method disclosed in the invention is compatible with the existing manufacturing process of a CSTBT device.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA

Gas turbine combustor with active fuel distribution control function

InactiveCN106091009AIncrease the degree of premixingEmission reductionContinuous combustion chamberCombustion chamberCombustor
Disclosed is a gas turbine combustor with an active fuel distribution control function. The gas turbine combustor comprises an end cover, a fixing plate and a fuel distribution control unit. The fuel distribution control unit comprises a motor, a transmission mechanism and a rotating plate. The end cover is fixedly connected with the fixing plate, and an internal cavity is formed between the end cover and the fixing plate. The fixing plate is provided with K positioning holes located at a first circumference, and a main fuel tube is arranged in each positioning hole. The motor is arranged outside the end cover. The rotating plate is arranged in the internal cavity. The motor is connected with the rotating plate through the transmission mechanism. The rotating plate is provided with m groups of allocation holes located at a second circumference. The numbers Qi of the allocation holes in the groups are different, and Qi is smaller than or equal to K. The motor drives the rotating plate to rotate so that the i group of allocating holes can be aligned with the Qi main fuel tube, and accordingly Qi main fuel channels are formed. According to the gas turbine combustor, different numbers of main fuel channels are formed on different load conditions, so that the combustion stability of the combustor is guaranteed and the pollution emission amount is lowered.
Owner:HARBIN INST OF TECH

Insulated gate bipolar translator (IGBT) device with two short-circuit positive electrodes

The invention discloses an insulated gate bipolar translator (IGBT) device with two short-circuit positive electrodes, and belongs to the technical field of semiconductor power devices. A positive electrode structure of the device is a two-positive-electrode short-circuit structure. The IGBT device comprises a first P+ hole emission layer, a second P+ hole emission layer, a metal collector and a silicon dioxide barrier layer, wherein the silicon dioxide barrier layer is positioned on the back face of the first P+ hole emission layer; the metal collector is positioned on the side face of the first P+ hole emission layer and below the second P+ hole emission layer, and the two P+ hole emission layers are contacted with each other; the second P+ hole emission layer is positioned at the bottom of an N- drift region and staggered in parallel with the first P+ hole emission layer; and an electronic trench is formed between the first P+ hole emission layer and the second P+ hole emission layer. The positive electrode structure of the IGBT device is improved, so that the hole injection efficiency is improved, the current carrier concentration distribution in the drift region is optimized, the conductivity modulation performance in the device body is improved, a negative differential resistance (NDR) region is eliminated effectively, the cut-off loss of the IGBT device is reduced effectively, and finally, compromise optimization for conductivity pressure drop and cut-off loss is realized.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA +1

Trench gate charge storage type IGBT (Insulated Gate Bipolar Translator) and manufacturing method thereof

The invention relates to a trench gate charge storage type IGBT (Insulated Gate Bipolar Translator), and belongs to the technical field of semiconductor power devices. According to the invention, a shielding trench structure which is equipotential with emitter metal is introduced on the basis of the traditional CSTBT device structure, and the trench depth of the shielding trench structure is enabled to be greater than that of a charge storage layer so as to shield an electric field of the charge storage layer. The introduction of the shielding trench structure plays an effective charge compensation effect for the charge storage layer, thus improves restrictions imposed on withstand voltage of the device by the doping concentration and thickness of the charge storage layer, and improves thebreakdown voltage of the device, thereby being conducive to improving the compromise between forward turn-on voltage drop Vceon and turn-off loss Eoff of the device, obtaining a wider short-circuit safe working area, being conducive to reducing the saturation current density of the device at the same time, and further improving the short-circuit safe working area of the device. In addition, the trench gate charge storage type IGBT significantly reduces the grid capacitance of the device and especially reduces the grid-collector capacitance, so that the switching speed of the device is improved, and the switching loss of the device and requirements for the ability of a gate driving circuit are reduced.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA

Granularity-controllable magnesium hydroxide reaction crystallization apparatus and process

The invention discloses a granularity-controllable magnesium hydroxide reaction crystallization apparatus and process. The reaction crystallization apparatus consists of a reaction crystallizer (1), a conveying pump (2) and a pipeline (3). The reaction crystallizer (1) comprises a jacket-type kettle body (4), a guide barrel (5), a longitudinal separation plate (6), a stirring paddle (7), an electric stirrer (8), a magnesium chloride feeding pipe (9), a sodium hydroxide feeding pipe (10), a feed distributor (11), a magnesium hydroxide discharging pipe (12) and a magnesium hydroxide feeding pipe (13). The invention also provides the magnesium hydroxide reaction crystallization process. By utilizing the apparatus and the process provided by the invention, the granularity-controllable production of the magnesium hydroxide can be realized, the magnesium hydroxide with different granularities can be prepared, and the requirements of different users on the granularity of a magnesium hydroxide product can be met. The granularity-controllable magnesium hydroxide reaction crystallization apparatus and process have the advantages of flexibility and adjustability in product granularity and narrow granularity distribution.
Owner:HEBEI UNIVERSITY OF SCIENCE AND TECHNOLOGY

Double split trench gate charge storage type insulated gate bipolar transistor (IGBT) and manufacturing method thereof

The present invention belongs to the power semiconductor device technology field, in particular relates to a trench gate charge storage type IGBT. According to the present invention, by introducing a double split electrode equipotential with an emitter and a dielectric layer between the double split electrode and a gate electrode at the bottom and the side surface of the gate electrode in a device trench, and on the condition of not influencing the threshold voltage and the conduction of the IGBT, the grid capacitance is reduced, thereby improving the switching speed of the device, and reducing the switching loss of the device. Meanwhile, a wide bottom split electrode and a floating P-type base region further enable the carrier concentration distribution of a whole N-type drift region to be improved, and enable a short circuit safe operating area, a breakdown characteristic, the performance and the reliability of the device to be improved. The manufacturing method of the double split trench gate charge storage type IGBT provided by the present invention does not need the additional process steps, and is compatible with a conventional trench gate charge storage type insulated gate bipolar transistor manufacturing method.
Owner:UNIV OF ELECTRONIC SCI & TECH OF CHINA

A charge storage type insulated gate bipolar transistor and a preparation method thereof

The invention relates to a charge storage type insulated gate bipolar transistor and a preparation method thereof, belonging to the technical field of power semiconductors. By improving the charge storage layer of the traditional charge storage type IGBT device, a semiconductor material used for the charge storage layer remote from the drift region has a larger band gap than a semiconductor material used for the charge storage layer close to the drift region, so that the semiconductor materials with different forbidden band widths form the same-type heterojunction at their contact interfaces,thereby forming a potential barrier that prevents minority carriers in the drift region from entering the base region. As a result, the carrier distribution concentration in the drift region is improved, the conductivity modulation effect of the IGBT is enhanced, the forward conduction voltage drop Vceon of the device is reduced, the breakdown voltage of the IGBT is optimized, and the tradeoff between the forward conduction voltage drop Vceon and the shutdown loss Eoff is achieved. Moreover, by adjusting the doping concentration of materials with different bandgap widths in the charge storagelayer and the combination of materials with different bandgap widths, the invention can further optimize the working characteristics of the device.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA

An insulated gate bipolar transistor and a preparation method thereof

The invention relates to an insulated gate bipolar transistor and a preparation method thereof, belonging to the technical field of power semiconductors. On the basis of the traditional charge storagetype IGBT device structure, A heterojunction structure is formed in the base region, thereby forming a potential barrier that prevents minority carriers in the drift region from flowing into the baseregion, thereby greatly increasing the minority carrier concentration near the emitter side in the drift region, The carrier concentration distribution in drift region is improved and the conductivity modulation effect of IGBT is enhanced, which reduces the forward conduction voltage drop Vceon and optimizes the tradeoff between the forward conduction voltage drop Vceon and the shutdown loss Eoffof IGBT. It overcomes the shortcoming that the traditional charge storage layer reduces Vceon and breakdown voltage at the same time. Moreover, the device performance can be further optimized by adjusting the combination of semiconductor materials with different forbidden band widths to form heterojunction structures.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA

Bidirectional IGBT and manufacturing method therefor

The invention discloses a bidirectional IGBT and a manufacturing method therefor, and belongs to the technical field of power semiconductor devices. According to the invention, a split electrode whichis equipotential with a surface metal and a thick dielectric layer located at a peripheral side of the split electrode are introduced to a conventional trench gate structure, and a floating P-type body region is introduced to one side of a split trench gate structure, thereby achieving the symmetric forwarding and reverse on / off characteristics of an IGBT structure under the condition that a threshold voltage and connection of an IGBT device are not affected. The adverse effect caused by the Miller effect is improved, and the drive power consumption is reduced. The current and voltage oscillation and EMI problems are avoided in a start dynamic process of the device. The short-circuit safety working area of the device is improved. The gate capacitance is reduced, the switching speed of thedevice is improved, and the switching loss of the device is reduced. The concentration of an electric field at the bottom of a trench is improved, and the breakdown voltage of the device is improved.The carrier enhancement effect of an emitter electrode is improved, the carrier concentration distribution of the whole N-type drift region is improved, and the compromise between the forwarding conduction voltage drop and switching-off loss is improved.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA

Non-uniform blanking method for aluminum electrolytic bath

InactiveCN105839145AGuaranteed uptimeReduce regional concentration differencesElectrolysisComputer science
The invention discloses a non-uniform feeding method for an aluminum electrolytic cell. According to the characteristics of the flow form of the electrolyte in the tank and the distribution of the alumina concentration, the capacity of the constant container at each feeding point is selected, and the obtained constant container is configured using a simulation method. Carry out comparative evaluation to determine the appropriate non-uniform constant container configuration; at the same time, according to the selected constant container capacity, adjust the feeding interval to ensure that the total feeding volume of the electrolytic cell remains unchanged within a certain period of time. By applying the method of the present invention, the size of each constant container can be adjusted in a targeted manner according to the difference in the flow characteristics of each region of the electrolyte in the cell, the regional concentration difference of alumina in the electrolyte can be reduced, the concentration distribution of alumina can be optimized, and the smooth operation of the electrolytic cell can be promoted.
Owner:CENT SOUTH UNIV

Semiconductor Storage Device and Method for Manufacturing the Same

[Problems] To provide a semiconductor storage device with excellent electrical characteristics (write / erase characteristics) by means of favorable nitrogen concentration profile of a gate insulating film, and to provide a method for manufacturing such a device.[Means for Solving Problems] a semiconductor device fabricating method according to a first aspect of the invention, a method for fabricating a semiconductor storage device that operates by transferring charges through a gate insulating film formed between a semiconductor substrate and a gate electrode, includes a step for introducing an oxynitriding species previously diluted by plasma excitation gas, into a plasma processing apparatus, generating an oxynitriding species by means of a plasma, and forming an oxynitride film on the semiconductor substrate as the gate insulating film. The oxynitriding species contains NO gas at a ratio of 0.00001 to 0.01% to the total volume of gas introduced into the plasma processing apparatus.
Owner:TOKYO ELECTRON LTD +1

Preparation method of organic silicon modified antibacterial waterborne polyurethane

The invention discloses a preparation method of organic silicon modified antibacterial waterborne polyurethane. The preparation method comprises the following steps: 1) carrying out vacuum dehydrationon polymer dihydric alcohol for 1 to 3 hours at 85 to 120 DEG C to obtain a product A; 2) cooling a temperature of the product A to 35 to 70 DEG C, then adding diisocyanate and a catalyst I into theproduct A to obtain a mixture, and performing stirring and reaction on the mixture under nitrogen protection to obtain a product B; 3) adding a chain extender I and a chain extender II into the product B, and performing reaction for 1 to 9 hours at 40 to 85 DEG C to obtain a product C; 4) cooling a temperature of the product C to 35 to 40 DEG C, adding a suitable amount of acetone for viscosity reduction, then adding alkoxy silane with secondary amino and performing reaction for 2 to 12 hours to obtain a product D; 5) adding an antibacterial agent containing an alkoxy silicone group into the product D to obtain a mixture, powerfully stirring the mixture at stirring speed of 800rpm or above, adding water into the mixture and removing the acetone to obtain the anti-pollution antibacterial waterborne polyurethane with solid content of 10 to 40 percent. The preparation method of the organic silicon modified antibacterial waterborne polyurethane has the characteristics of good antibacterialperformance, low cost, simple process, environmental protection, high water resistance and mechanical strength, high hardness and difficulty in softening.
Owner:QIANNAN NORMAL UNIV FOR NATTIES

Ultraviolet light-emitting diode (LED) epitaxial structure and growth method thereof

The invention provides an ultraviolet light-emitting diode (LED) epitaxial structure. The epitaxial structure sequentially comprises an AlN Buffer layer, a high-temperature UGaN layer, a composite N-type GaN layer, a multi-quantum well (MQW) structure, an active region light-emitting quantum-well layer, an electron blocking layer (EBL) and a P-type GaN layer from bottom to top, wherein the active region light-emitting quantum-well layer comprises n layers of In<x>Ga<1-x>N / Al<y>Ga<1-y>N multi-quantum wells, each layer of In<x>Ga<1-x>N / Al<y>Ga<1-y>N multi-quantum well comprises a main barrier and a movable barrier, the movable barrier is embedded into the main barrier, the main barrier comprises Al<y>Ga<1-y>N, the height of the main barrier is gradiently increased with the increase of Al constituent, the movable barrier comprises GaN, and the thickness of each layer of movable barrier is 1-20 nanometers. By the ultraviolet LED epitaxial structure and a growth method thereof, the stress in the quantum wells is reduced, the hole injection efficiency is improved, electrons of an active layer is prevented from overflowing, and the carrier recombination probability and the internal quantum efficiency of an ultraviolet LED are improved.
Owner:宁波安芯美半导体有限公司

Formation method of fin field effect transistor

A formation method of a fin field effect transistor comprises the steps of providing a substrate, wherein fin parts are formed on the surface of the substrate, and the fin parts comprise a first fin part and a second fin part located on the top surface of the first fin part; forming a sacrificial layer on the surface of the substrate, wherein the surface of the side wall of the first fin part is also covered by the sacrificial layer; forming a side wall film covering the surfaces of the sacrificial layer and the second fin part; back etching the side wall film, and forming a side wall on the surface of the side wall of the second fin part; etching and removing the sacrificial layer and exposing the surface of the side wall of the first fin part; forming a conductive layer on the surfaces of the substrate and the side wall of the first fin part, wherein anti-punchthrough ions are contained in the conductive layer; forming a dielectric layer on the surface of the conductive layer, wherein the dielectric layer is exposed out of the surface of the side wall; and removing the side wall. The method of the present invention enables the electrical property of the formed fin field effect transistor to be improved.
Owner:SEMICON MFG INT (SHANGHAI) CORP +1

High-strength toughness carburized and air-cooled steel for tunneling tool and production method thereof

The invention discloses high-strength toughness carburized and air-cooled steel for a tunneling tool and a production method thereof. The steel comprises the following ingredients in percentage by weight: 0.1-0.40% of C, 0.7-1.3% of Si, 1.7-2.4% of Mn, 0.1-0.3% of Mo, 0.04-0.2% of V, 0.70-2.0% of Cr, 0.01-0.02% of rare earth elements Ce and La and the balance of iron. The production method comprises the following steps of: smelting the materials into an ingot blank in the ratio, forging and rolling into a finished material at the temperature of 1100 DEG C, heating at the temperature of 900 DEG C, and then carrying out air cooling, namely obtaining a bainite structure at a cooling rate of 1-100 DEG C / min, obtaining a bainite+martensite structure at a cooling rate of 100-200 DEG C / min, and annealing at the temperature of 100-300 DEG C; and carburizing the steel at the temperature of 900-920 DEG C, and then carrying out conventional air cooling at a cooling rate of 10-200 DEG C / min. The production method disclosed by the invention has the beneficial effects that toughness and ductility can be enhanced, optimal strength and toughness combination is formed between the material and components such as the tunnelling tool, and the service life and fatigue life of the tunnelling tool are obviously prolonged.
Owner:贵州惠沣众一机械制造有限公司

Magnetic control chemical chain combustion reaction device and method

The invention relates to a magnetic control chemical chain combustion reaction device and method and belongs to the field of chemical chain combustion. The magnetic control chemical chain combustion reaction device comprises a fuel reaction channel, an air reaction channel, a cyclone separator, three magnetic field generators and a rotary magnetic field generation device, wherein a body of each magnetic field generator is a cavity; the two ends of each cavity are wound with magnet exciting coils; the magnetic field generators are horizontally arranged; the fuel reaction channel penetrates through the cavities of all the magnetic field generators and is divided into a magnetic field section a and a non-magnetic field section b by the magnetic field generators; and the rotary magnetic field generation device makes magnetic oxygen carriers reduced in the fuel reaction channel rapidly enter the air reaction channel by the magnetic force function. Compared with a traditional chemical chain CH4 gas fuel combustion device, the problem of oxygen carrier agglomeration is solved, and deoxidation carriers are subjected to movement and a reaction in the reaction device automatically, controllably and efficiently.
Owner:NORTHEASTERN UNIV

Preparation method of field stop insulated-gate bipolar transistor

The invention provides a preparation method of a field stop insulated-gate bipolar transistor. The method comprises the steps as follows: a P-type substrate is provided; N-type impurities are implanted into the P-type substrate twice, namely one-time arsenic ion implantation and one-time phosphorus ion implantation; the implantation energy of phosphorus ion implantation is greater than that of arsenic ion implantation; heat diffusion is carried out to form an N-type field stop layer; an N-type drift region is formed on the first surface of the field stop layer in an epitaxy manner; a front-side structure of the field stop insulated-gate bipolar transistor is formed; back thinning treatment is carried out on the P-type substrate; and back metalized treatment is carried out on the field stop insulated-gate bipolar transistor. By one-time low-energy arsenic implantation and one-time high-energy phosphorus implantation, N-type impurity concentration distribution of a field stop layer can be optimized by the difference between the arsenic ion diffusion rate and the phosphorus ion diffusion rate during twice implantation.
Owner:CSMC TECH FAB2 CO LTD

A three-phase flow reaction device for olefin hydroformylation and its operating method

The invention belongs to the field of reactor engineering, and relates to a three-phase flow reaction device for olefin hydroformylation, which includes a reactor, a heat exchanger and a gas distributor, and the center of the top of the heat exchanger passes through a pipe bent at right angles It communicates with the reactor, and the center of its bottom end is also communicated with the reactor through a pipe, and an axial flow pump is provided at the bend of the pipe from the bottom end, and the gas distributor is set at the bottom end of the reactor, and the reactor There is also a wire mesh demister horizontally arranged inside the upper end of the tank. The present invention is used for the hydroformylation reaction through the coupling of the gas-liquid-solid three-phase circulating fluidized reactor and the heat exchanger, so that the liquid-solid phase forms a dynamic circulation between the reactor and the tubular heat exchanger, The mass transfer and heat transfer process is effectively promoted, the conversion rate of raw gas and the selectivity of target product aldehydes are significantly improved, the total heat transfer coefficient of the heat exchanger is increased, and the required heat transfer area is reduced; through the gas-liquid-solid three-phase Fluidization realizes the good effect of promoting reaction mass transfer and heat transfer of external circulation heat exchanger.
Owner:河南能源集团研究总院有限公司

Charge storage type insulated gate bipolar transistor and preparation method thereof

The invention discloses a charge storage type insulated gate bipolar transistor and a preparation method thereof, and belongs to the technical field of power semiconductors. On the basis of a traditional charge storage type IGBT device structure, a charge storage layer and a drift region form a heterojunction structure, so that the energy band on one side, close to an emitting electrode, of the drift region is bent, so as to form a barrier for blocking a few carriers in the drift region from flowing away from a base region, and the concentration of a few carriers in the current position is increased. According to the invention, the carrier distribution concentration of the drift region is improved, and the conductance modulation effect of the IGBT is enhanced, so that the positive conducting voltage drop Vceon of the device is reduced, and the compromise between the positive conducting voltage drop Vceon of the IGBT and the turn-off loss Eoff is optimized; and the defect that the breakdown voltage is reduced when the Vceon of the traditional charge storage layer is reduced is overcome; and a combination of different forbidden band width semiconductor materials for forming the heterojunction structure can be adjusted, so that the working characteristics of the device can be further optimized.
Owner:UNIV OF ELECTRONIC SCI & TECH OF CHINA
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