259results about How to "Fast switching speed" patented technology

The invention provides a low-on-resistance trench gate silicon carbide VDMOS and a preparation method thereof, and the method comprises the steps: depositing metal on the lower side surface of a silicon carbide substrate, and forming a drain metal layer; epitaxially growing on the upper side surface of the silicon carbide substrate to form a drift layer; performing ion implantation to form a low-resistance region; forming a barrier layer, etching, performing ion implantation, and forming a P + well region, a P-type well region and an N-type source region; a barrier layer is formed again, and the insulating medium is etched and deposited; forming a barrier layer again, etching and depositing metal, and forming a suspension gate; forming a barrier layer again, etching the barrier layer, and depositing to form an insulating medium layer; forming a barrier layer again, etching and depositing metal, and forming a gate metal layer; the barrier layer is re-formed, the barrier layer is etched to form a through hole, the drift layer is etched to the upper side face of the P-type well region, metal is deposited, a source electrode metal layer is formed, the barrier layer is removed, preparation is completed, gate-drain capacitance is reduced, the switching speed of the device is increased, and switching loss is reduced.

The invention provides a heterogeneous trench gate silicon carbide VDMOS and a preparation method thereof, and the method comprises the steps: depositing metal on the lower side surface of a silicon carbide substrate, and forming a drain metal layer; epitaxially growing on the upper side surface of the silicon carbide substrate to form a drift layer; forming a barrier layer above the drift layer, and performing etching and ion implantation to form a P-type well region, an N-type source region and a masking region; forming a barrier layer again, and etching and depositing the insulating medium to form a first insulating medium region; forming a barrier layer again, and etching to form a groove; forming a barrier layer again, etching and depositing metal, and forming a suspension gate; forming a barrier layer again, and etching and depositing the insulating medium to form a second insulating medium region; forming a barrier layer again, etching and depositing metal, and forming a gate metal layer; the preparation method comprises the following steps: preparing a source electrode metal layer, re-forming a barrier layer, etching, depositing metal, forming a source electrode metal layer, removing the barrier layer, and completing the preparation, thereby realizing the characteristics of low switching loss, high switching speed and low on-resistance.

The invention discloses an asphalt viscosity testing device for road and bridge construction, and relates to the technical field of asphalt viscosity testing. Liquid asphalt reaching the detection temperature circularly flows between the heating mechanism and the viscosity testing mechanism, so that the asphalt can be continuously heated in the flowing process, the temperature of the asphalt is kept in a relatively stable state, and the inner walls of components such as a conveying pipe and a return pipe can be heated in the long-time flowing process of the asphalt, so that the viscosity of the asphalt is improved. Before the asphalt viscosity is detected, the temperature of the asphalt and the temperature of a component in contact with the asphalt can be kept consistent, so that the condition of heat loss before the asphalt is detected is avoided, and the accuracy of asphalt viscosity detection can be improved; the plurality of viscosity testing units are used for synchronously testing the viscosity of the asphalt at a plurality of positions at the same time, and the viscosity value of the asphalt at the testing temperature can be comprehensively evaluated, so that the condition that the testing data have relatively large deviation due to misoperation or equipment failure is avoided.

The invention relates to a novel asymmetric groove SiC MOSFET device with low resistance and Miller capacitance, and belongs to the technical field of semiconductor devices. The device comprises a substrate; the drift region is formed on one surface of the substrate; the N-CSL is formed on the surface of the drift region; the low-barrier diode is formed on one side of the surface of the N-CSL; the second P-well is formed on the other side of the surface of the N-CSL; the trench gate and the auxiliary trench gate are formed on the surface of the low-barrier diode and located on the two sides of the low-barrier diode; the P-base is formed on the surface of the N-CSL and is positioned between the second P-well and the trench gate; the source N + region is formed on the surface of the P-base and is positioned between the second P-well and the trench gate; a source electrode formed on the top of the device; and the drain electrode is formed on the other surface of the substrate. The specific on-resistance of the device can be reduced, the Miller capacitance and the gate charge of the device are reduced, and the switching speed of the device is improved.

The invention provides a varied doping high-reliability planar gate silicon carbide VDMOS and a preparation method thereof, and the method comprises the steps: depositing metal on the lower side surface of a silicon carbide substrate, and forming a drain metal layer; epitaxially growing on the upper side surface of the silicon carbide substrate to form a drift layer; a barrier layer is formed, etching and ion implantation are carried out, and a first N-type region, a second N-type region and a P-type well region are formed; a barrier layer is formed again, etching and ion implantation are carried out, and an N-type source region is formed; a barrier layer is formed again, etching and ion implantation are carried out, and a third N-type region is formed; a barrier layer is formed again, and a gate dielectric layer is formed through etching and deposition; and re-forming a barrier layer, etching, depositing metal, forming a gate metal layer and a source metal layer, and removing the barrier layer to complete preparation. The transverse layout of the on-resistance of the device is accurately controlled, so that the current is uniformly distributed in the device, heat concentration is avoided, and the reliability of the device is improved.

The invention discloses a power device and a preparation method thereof, a power module, a power conversion circuit and a vehicle, and the power device comprises a semiconductor body which comprises a first surface and a second surface which are oppositely arranged, and also comprises a well region and a contact region; the well region is at least located at one side of the contact region adjacent to the second surface; the gate structure is located on the first surface; the first piezoelectric material layer is located on one side of the gate structure away from the second surface; the first piezoelectric material layer covers the gate structure and a part of the contact region; the first electrode layer is located on the second surface; the first electrode layer comprises a first electrode and a second piezoelectric material layer, and the second piezoelectric material layer is located on the side, away from the second surface, of the first electrode; the second piezoelectric material layer is provided with a plurality of cavities, and the plurality of cavities penetrate through the second piezoelectric material layer; the first electrode covers the second surface, and the plurality of cavities are filled with the first electrode. The power consumption can be reduced, and the switching speed and the conductivity of the device can be improved.

The invention discloses a split gate IGBT (Insulated Gate Bipolar Translator) structure, and belongs to the field of semiconductor devices. Comprising collector metal, a P-type collector region, an N-type field stop layer and an N-type drift region which are sequentially arranged from bottom to top, an N-type storage layer, a P-type body region and emitter metal are sequentially arranged above the N-type drift region, an N + contact region is arranged in the P-type body region, a first oxide layer medium is arranged in the middle of the bottom of the emitter metal, a cross-shaped groove is formed in the N-type drift region, and a second oxide layer medium is arranged in the cross-shaped groove. The cross-shaped groove divides the N-type drift region, the N-type storage layer, the P-type body region and the N + contact region into a left part and a right part. The top of the cross-shaped groove is provided with a gate oxide layer, the bottom of the cross-shaped groove is provided with a second oxide layer medium, the top of the cross-shaped groove is provided with gate polycrystalline silicon which divides the gate oxide layer into a left part and a right part, and the left wide part and the right wide part of the cross-shaped groove are both internally provided with separation gate polycrystalline silicon. According to the split gate IGBT structure provided by the invention, the Miller capacitance and the conduction voltage drop can be effectively reduced.

The invention discloses a frequency band switching method and device for a vehicle-mounted hot spot, a medium and electronic equipment. The method comprises the following steps: acquiring first signal intensity, first interference intensity and first network quality of the vehicle-mounted hot spot in a current connection frequency band; jointly judging whether the first signal strength, the first interference strength and the first network quality meet a first parameter condition or not; if yes, obtaining a target connection frequency band; and switching the vehicle-mounted hotspot from the current connection frequency band to the target connection frequency band. According to the invention, the frequency band switching speed can be improved.

Disclosed is a display device with a switchable viewing angle. According to an exemplary embodiment of the present disclosure, the display device having a switchable viewing angle includes: a first polarizer that transmits P-wave or S-wave light; a viewing angle control layer disposed above the first polarizer and including a lower electrode and an upper electrode, and a liquid crystal layer disposed between the lower electrode and the upper electrode to selectively change light of the P-wave or the S-wave to the S-wave or the P-wave; and a second polarizer disposed over the viewing angle control layer and having a transmission axis perpendicular to the transmission axis of the first polarizer. Accordingly, a mode may be switched to a privacy mode and a sharing mode, and in the sharing mode, brightness may be improved without increasing power consumption.

The invention provides a video image processing method and device of an unmanned aerial vehicle pan-tilt camera and a storage medium. The method comprises the steps of collecting multiple paths of first yuv images; rTSP protocol communication between the client and the pan-tilt camera is established; in response to the acquired lens switching instruction sent by the client, acquiring a corresponding first yuv image according to the lens switching instruction; in response to the condition that the original resolution of the obtained first yuv image is different from the target resolution, zooming the first yuv image to a preset resolution to obtain a second yuv image, creating a first memory area based on the preset resolution, and carrying and storing the second yuv image to the first memory area by using ive operation; creating a second memory area based on the target resolution, creating a blank yuv image of the target resolution and storing the blank yuv image in the second memory area, and setting the yuv value of the blank yuv image to be a black pixel value by using ive operation to obtain a filled yuv image; and carrying and covering the second yuv image to the filled yuv image by using ive operation to obtain a first target yuv image.

The utility model discloses an IGBT (Insulated Gate Bipolar Transistor) protection circuit, which comprises a driving module, the input control end of the driving module is connected with the cathode of a Zener diode D0, and the cathode of the Zener diode D0 is also connected to the emitter E of an insulated gate bipolar transistor Q0. The grid electrode G of the insulated gate bipolar transistor Q0 is connected to the driving output end of the driving module through a resistor R6, and the collector electrode C of the insulated gate bipolar transistor Q0 is connected with the overcurrent detection output end of the driving module through a fast recovery diode FR107. According to the technical scheme, transient voltage spikes can be effectively restrained, the IGBT is protected against overvoltage damage, the anti-interference capacity of the circuit is enhanced, a fast recovery diode FR107 is further arranged at the overcurrent detection output end of the driving module, the switching speed can be increased, the overvoltage phenomenon during switching-off is reduced, the service life of the IGBT and the driving module is prolonged, and the service life of the IGBT and the driving module is prolonged. And the working reliability of the whole circuit is improved.

The utility model provides a high-voltage switch assembly and a power distribution switch. The high-voltage switch assembly comprises a plurality of SiC MOS tube modules, a control module and an isolation driving module connected with the SiC MOS tube modules. The SiC MOS tube module is connected to a direct current bus; any one of the SiC MOS tube modules is connected with one of the isolation driving modules; and the control module is connected to the isolation driving module so as to control the turn-off or turn-on of the SiC MOS tube module through the isolation driving module. The high-voltage direct-current system can meet the requirement of a power distribution network within the 1500V high-voltage direct-current level, and the cost of the high-voltage direct-current system is

The invention discloses a vertical 4H-SiC photoconductive switch, which comprises a SiC substrate, a front electrode, a passivation layer and a back electrode, and is characterized in that the front electrode is located on the upper surface of the SiC substrate, and the passivation layer is located on the upper surface of the SiC substrate and is arranged at the edge of the front electrode; the back electrode is located on the lower surface of the SiC substrate; wherein the front electrode comprises an annular electrode and a mesh electrode, and the mesh electrode is arranged in the inner circle of the annular electrode and connected with the annular electrode; a plurality of concentric terminal protection rings are also arranged in the SiC substrate below the outer side of the front electrode, and the circle centers of the longitudinal projections of the plurality of terminal protection rings coincide with the circle centers of the longitudinal projections of the annular electrodes. According to the structural design, the electric field concentration effect near the electrode caused by non-uniform distribution of the electric field on the surface of the photoconductive switch is relieved, premature breakdown of the device is avoided, and the voltage endurance capability of the photoconductive switch is doubled; and meanwhile, the uniformity of current distribution in the photoconductive switch is improved.

The utility model provides a power supply control circuit and security inspection equipment, and relates to the technical field of security inspection. The power supply control circuit comprises a first power supply module; one of the first power supply module and the second power supply module comprises an uninterruptible power supply unit, and the other one of the first power supply module and the second power supply module comprises a commercial power supply unit; the power supply switching module comprises a first end, a second end and a third end, the first end is connected with the first power supply module, the second end is connected with the second power supply module, and the third end is connected with a target device; the power supply switching module is configured to disconnect the first end and the third end when the power supply of the first end is abnormal, and connect the second end and the third end within a first preset time; when power supply of the first end returns to normal, the second end and the third end are disconnected, the first end and the third end are connected within a second preset time, and the first preset time and the second preset time are configured in the mode that when switching operation is executed, the target device does not lose power.

The invention discloses a low-cost all-vertical gallium nitride Schottky barrier diode and a preparation method thereof. The diode comprises a transmission layer; the drift layer is located on the lower surface of the transmission layer; the positive electrode is located in the middle of the lower surface of the drift layer; the negative electrode is located in the middle of the transmission layer; the first dielectric layer is located on the lower surface of the remaining drift layer and the side wall and part of the lower surface of the positive electrode; the second dielectric layer is located on the upper surface of the remaining transmission layer and the side wall and part of the upper surface of the negative electrode; the positive electrode thickening layer is located on the lower surface of the first dielectric layer and the lower surfaces of the remaining negative electrodes; the conductive substrate is positioned on the lower surface of the positive electrode thickening layer; the additional positive electrode is positioned in the middle of the lower surface of the conductive substrate; the negative electrode thickening layer is located on the upper surface of a part of the second dielectric layer and the upper surface of the remaining negative electrode. According to the invention, a completely longitudinal conductive vertical device structure is realized, the forward current density of the device is improved, and the on-resistance is reduced.

The invention provides a switching power supply and a driving circuit and a driving method thereof, the driving circuit comprises a level shift circuit, a pulse generation circuit, a high-side driving circuit and a low-side driving circuit, an output signal of the level shift circuit is used for adjusting the potential of a first node in the high-side driving circuit, and an output signal of the pulse generation circuit is used for adjusting the potential of a second node in the low-side driving circuit. The high-side driving circuit drives the high-side switch unit to be switched on after the potential of the first node reaches a switching-on trigger potential, and the high-side driving circuit drives the high-side switch unit to be switched on after detecting that the driving signal of the low-side switch unit is changed into an invalid state and the high-side control signal is changed into an effective state; an additional potential adjusting path is established for the first node, so that the time for the potential of the first node to reach the turn-on trigger potential is shortened, namely the dead zone time from turn-off of the low-side switch unit to turn-on of the high-side switch unit is shortened, the switching speed of the high-side switch unit is increased, the reduction of dead zone loss and switching loss is realized, and the switching efficiency is improved. And the working efficiency of the switching power supply is improved.

The utility model discloses a silicon carbide MOSFET device comprising at least one cell, and each cell comprises a silicon carbide substrate of a first doping type; an epitaxial layer of a first doping type; the well regions of the second doping type are located in the epitaxial layer, and JFET regions are arranged between the adjacent well regions; the source region of the first doping type is located in the well region; the contact region of the second doping type is located in the well region and is adjacent to the source region; the field oxide layer is located on the surface of the epitaxial layer and located above the JFET region; the gate oxide layer comprises a first gate oxide layer and a second gate oxide layer, and the first gate oxide layer and the second gate oxide layer are located on the two sides of the field oxide layer respectively and are adjacent to the field oxide layer respectively; the gate conductors comprise a first gate conductor and a second gate conductor, the first gate conductor covers the surface of the first gate oxide layer and part of the surface of the field oxide layer, the second gate oxide layer covers the surface of the second gate oxide layer and part of the surface of the field oxide layer, and the first gate conductor and the second gate conductor are separated from each other.

This invention discloses a contactless chip testing system. The platform includes a PC, a data parsing / forwarding module, a source signal excitation module, a gating array, and a chip slot under test. The platform allows for simultaneous multi-selection via a PC's visual interface, enabling automated integrated testing of resistance, capacitance, package integrity, voltage, and overall power consumption between any chip pins. Compared to traditional mechanical probe-based contact testing systems, this invention is more compact. Furthermore, it employs an automatically gating physical path switching method, resulting in a higher switching rate and more efficient package testing.

The utility model provides a semiconductor device and an IGBT chip. According to the semiconductor device, the temperature sensor is embedded between the adjacent power devices, so that the temperature of the device can be accurately monitored in real time in the device, the working temperature of the device can be timely regulated and controlled, and the first electrode layer can simultaneously cover the cellular area and a part of the temperature sensing area; therefore, the source region of the power device and the first end of the temperature sensor are short-circuited to form Kelvin contact, so that external stray inductance can be shielded, the switching speed of the device is improved, and the switching loss is reduced.

The present invention relates to a hub type automatic focusing lens, comprising a main mirror seat, an upper cover, a hub assembly, a motor assembly, a field of view positioning assembly and a limit switch, wherein the hub assembly and the motor assembly are both arranged in the main mirror seat, the upper cover is fixedly connected to one side of the main mirror seat, the limit switch is fixedly connected to the inner side of the upper cover, the motor assembly drives the hub assembly to rotate to 0° or 90°, the hub assembly is also provided with a trigger device for colliding and triggering the limit switch to stop the motor assembly, and the field of view positioning assembly is arranged on one side of the main mirror seat and is used to lock the hub assembly when it rotates to 0° or 90°. Beneficial effects: fast focusing speed and good optical axis consistency. The manufacturing and installation process requirements are relatively low, meeting the requirements of mass production. The azimuth direction is changed only by interactive transformation between the two positions of 0° and 90°, and the switching speed is extremely fast, meeting the requirements of fastness and maneuverability.

The invention discloses a GaN vertical complementary field effect transistor (VCFET) and an inverter, the VCFET comprises a substrate, a first transistor, a second transistor and a common gate electrode, and the first transistor and the second transistor are sequentially and vertically stacked on the substrate; the first transistor is an n-type transistor, the second transistor is a p-type transistor, and an integral structural form of a GaN buffer layer, an n-tube GaN channel layer, an AlGaN barrier layer, a p-tube GaN channel layer and a p-tube GaN doping layer is formed; the control of the n-type channel and the p-type channel at the same time is realized through a common gate electrode. On the basis of the structure, the source electrode of the p-type transistor is connected with a high level, the source electrode of the n-type transistor is connected with a low level, the drain electrodes of the two transistors are connected together and serve as an output end at the same time, and the gate electrodes serve as an input end, so that the phase inverter can be realized. According to the VCFET, the electronic transmission characteristics of high efficiency and low power consumption are realized, the occupied area is smaller while the high performance is maintained, and the integration level is improved.

The invention discloses a trench gate type IGBT (Insulated Gate Bipolar Translator) and a manufacturing method thereof, and belongs to the technical field of semiconductors, the manufacturing method of the trench gate type IGBT comprises the following steps: providing a substrate; etching the substrate to form a groove; depositing polycrystalline silicon at the bottom of the groove to form an emitter region; continuously depositing an insulating medium with a first preset height on the top of the emitter region; the two sides of the insulating medium are etched to form two containing cavities with second preset heights, and the second preset heights are smaller than the first preset height; depositing polycrystalline silicon in the accommodating cavity to form a gate region; the insulating medium between the two containing cavities continues to be etched, an opening extending to the emitter region is formed between the containing cavities, the critical size of the opening is smaller than the critical size of the remaining insulating medium, and the opening is filled with polycrystalline silicon so that the emitter region can be led out. By setting the relative positions of the gate region and the emitter region, the contact area of the collector and the gate region is reduced, so that the Cres of the IGBT can be reduced, the switching speed of the IGBT can be improved, and the switching loss of the IGBT can be reduced.

The present invention discloses a PNP type Schottky collector region AlGaN / GaN HBT device, which comprises, from bottom to top, a substrate, a buried oxide layer, a collector region, a base region and an emitter region, wherein the collector region comprises a lower P-type single crystal silicon layer and an upper metal silicide layer, the base region comprises an N-type AlGaN layer, and the emitter region comprises a P-type GaN layer; a collector electrode is arranged on the P-type single crystal silicon layer, a base electrode is arranged on the N-type AlGaN layer, and an emitter electrode is arranged on the P-type GaN layer. The present invention has good contact interface characteristics, can improve the switching speed and cut-off frequency of the device, has a simple process and is compatible with existing silicon-based processes.

The utility model belongs to electrical equipment, and particularly relates to a silicon carbide inversion induction heating power supply, which comprises a three-phase input circuit, a voltage chopper circuit, a silicon carbide inversion circuit, an output circuit and a connection relation thereof. The high-frequency induction heating power supply adopts the silicon carbide inverter, has the characteristics of large single-tube current, high switching speed, low on-resistance, low failure rate, small switching loss, high temperature resistance and the like, and greatly improves the inversion efficiency and reliability of the high-frequency induction heating power supply; an RDC inversion absorption plate is designed and is specially designed for high-frequency inversion of the SiC module, and due to the fact that the switching speed of the SiC module is high, high voltage can be generated when the SiC module is switched on and off, and the RDC inversion absorption plate can be used for absorption in time; a transformer RC absorption assembly is further designed, is connected in parallel to the two ends of a primary winding of the isolation transformer and is used for absorbing high-frequency parasitic oscillation generated by the primary side of the transformer, preventing the output end of the inverter bridge from generating high-frequency parasitic oscillation current, reducing oscillation current of the SiC module and reducing heating of the SiC module.

The application relates to a full GaN power electronic monolithic integrated circuit and a preparation method thereof, which comprises, from bottom to top, an insulating composite substrate, an AlN layer, a Si layer, a GaN / AlGaN buffer layer, a GaN layer and an AlGaN layer; a 2DEG layer is formed between the GaN layer and the AlGaN layer; the AlGaN layer is etched, a p-GaN layer is grown; a p-GaN layer gate portion is etched and filled with a passivation layer, and a gate metal is grown; source metal and drain metal are respectively grown on both sides of the p-GaN layer gate area; a deep groove is arranged between a driving circuit and a low-voltage tube, between a high-voltage tube and the low-voltage tube, and a medium is filled in the deep groove; and the full GaN power electronic monolithic integrated circuit is obtained through a top via and an interconnection process. The application can realize high efficiency and low power consumption, low parasitic effect, and reduce leakage current and switching loss.

The invention discloses a solid polymer electrolyte adhesive film for an electrochromic device as well as a preparation method and application of the solid polymer electrolyte adhesive film. The preparation method comprises the following steps: heating and premixing an ethylene-vinyl acetate copolymer and a lithium salt additive to prepare a first solid product; and carrying out rolling treatment and constant-temperature and constant-humidity treatment on the first solid product to prepare the solid polymer electrolyte adhesive film for the electrochromic device. The solid polymer electrolyte adhesive film prepared by the method has relatively high ionic conductivity and good optical and thermal properties and mechanical properties, and meanwhile, meets the processing and application requirements of sandwich type WO3-NiO electrochromic devices.

The application relates to the technical field of heat exchange, and discloses a column-tube type heat exchanger for fluid heat exchange, which comprises a shell, the inside of the shell is uniformly distributed with inner mounting plates, the outside of the inner mounting plates is rotationally connected with outer mounting plates, the inside of the shell is provided with two inner end plates, the outside of the inner end plates is rotationally connected with outer end plates, the outside of one side of the outer end plates is fixedly connected with a ratchet wheel, the inside of the other side of the outer end plates is rotationally connected with a fixing frame, the upper end of a driving bin two is slidably connected with a sliding shaft, and the upper end of the sliding shaft is fixedly connected with a limiting block. Through the relative rotation of the outer mounting plates and the inner mounting plates, the window area and the flow position of the clear water flow channel formed between the outer mounting plates and the inner mounting plates continuously and dynamically change, the clear water in the shell is forced to continuously change the flow direction, the clear water is prevented from long-term flowing through the local heat exchange area along the fixed flow channel, the outer surfaces of all the heat exchange tubes can be fully contacted with the low-temperature clear water, and balanced and deep heat exchange of the whole tube area is realized.

The utility model relates to electrical measurement and automation test technical field, concretely relates to a kind of AC-DC withstand voltage insulation tester, it includes: main control unit, for executing test program and controlling each module coordinated work;High voltage output module, for generating the AC / DC high voltage required by test;Precise current detection module, for detecting the leakage current of measured piece;Multi-channel test interface, for connecting multiple measured equipment;Automatic switching unit, for automatically switching test channel;Data storage module, for automatically recording test data;Man-machine interface, for displaying test information and receiving operation instruction.The utility model is jointly constituted by innovative design an advanced test system with automation, high precision, high efficiency, intelligent management in one, realizes qualitative leap in test quality, operation convenience, production efficiency and safety etc., fully meets the rigorous requirement of modern industry to electrical safety test equipment.