11results about How to "High breakdown field strength" patented technology

The invention provides a high-k gate dielectric composite material, a preparation method thereof and a beta-Ga2O3 MOS (Metal Oxide Semiconductor) power device. The composite material comprises a beta-Ga2O3 substrate; the SiO2 interface buffer layer is formed on at least one surface of the beta-Ga2O3 substrate; the Al2O3 transition layer is formed on the surface of the SiO2 interface buffer layer; the AlON interface layer is formed on the surface of the Al2O3 transition layer; and the HfO2 high-k main dielectric layer is formed on the surface of the AlON interface layer. Experimental results show that the composite material provided by the invention has a dielectric constant of 15-30, a forbidden bandwidth of greater than 5eV, an interface state density of less than 1 * 10 < 12 > cm <-2 > eV <-1 > and a breakdown field strength of 7MV / cm-15MV / cm, can effectively improve the interface characteristics of a beta-Ga2O3 MOS power device when being used for the beta-Ga2O3 MOS power device, improves the reliability of a gate medium, and is suitable for being applied to high-voltage and high-temperature power devices.

The present disclosure relates to a complex-phase ceramic and a preparation method and application thereof, the electrical performance of the ceramic single crystal boundary is improved by introducing yttrium element and complex phase, and then the electrical performance of the entire ceramic system is improved; the prepared yttrium element doped calcium copper titanate and strontium copper titanate complex phase ceramic system has excellent breakdown field strength and giant dielectric performance, and can improve the performance of capacitor energy storage elements, memory functional devices, multilayer ceramic capacitors and other functional devices.

The invention discloses a polyimide dielectric film containing carboxyl betaine and a preparation method thereof. The carboxyl betaine-containing polyimide dielectric film is prepared from carboxyl betaine-containing polyimide, and the carboxyl betaine-containing polyimide is prepared by the following steps: firstly, taking a precursor of carboxyl betaine, m-phenylenediamine and bisphenol a type diether dianhydride as monomers, and carrying out condensation polymerization to obtain polyamide acid; carrying out complete imidization on the polyamide acid under the action of a catalyst isoquinoline to obtain polyimide containing a precursor; and reacting the polyimide containing the precursor with sodium bromoacetate to obtain polyimide containing carboxyl betaine. The zwitterions are introduced into the polyimide structure to improve the dielectric and energy storage performance of the polyimide dielectric film, and meanwhile, the preparation method has the advantages of being low in cost, simple in process, controllable and adjustable in performance, suitable for large-scale application and the like.

The application discloses an iron-based barium sodium niobate ceramic material with high energy storage performance and a preparation method thereof. 4‑2x Sm 2x Na2Fe x Nb 10‑x O 30 , wherein 1<=x<=1.25. Barium carbonate, samarium oxide, sodium carbonate, ferrous oxide and niobium pentoxide are used as raw materials, and a standard solid-phase method is adopted to sinter the iron-based barium sodium niobate ceramic material. In the product formula, iron is used to replace niobium in the barium sodium niobate, which is lead-free, environment-friendly, rich in iron reserves and low in price, and is beneficial to control the cost of raw materials. In addition, the iron replacement is beneficial to enhance the relaxor ferroelectric performance of the material, can obtain a more slender hysteresis loop, and improves the energy storage efficiency of the material. The prepared ceramic material has few pores and cracks, high density, and the microstructure is obviously improved, the grain size is more fine and uniform, the ferroelectric polarization intensity and the breakdown field strength are significantly improved, the problem that the barium sodium niobate material is difficult to sinter is solved, and the ferroelectric performance and the energy storage performance are significantly improved.

The invention provides a diamond device and a preparation method thereof, and relates to the technical field of diamond devices. The device comprises a diamond substrate; a conducting channel is arranged on the diamond substrate; one side of the conductive channel is provided with a source electrode, and the other side is provided with a drain electrode. A graphite grid electrode is embedded in the diamond substrate under the conducting channel; and the diamond substrate surrounds the graphite grid electrode on the whole circumference in a cross section perpendicular to the direction of the source-drain connecting line. A grid electrode is arranged below a conducting channel, and a graphite grid electrode with a buried grid structure is arranged in a diamond substrate. The in-situ diamond between the graphite grid electrode and the conductive channel plays a role of grid insulation. The in-situ diamond material has extremely high breakdown field strength, and the high-quality in-situ diamond is used as the gate medium, so that the breakdown characteristic of the diamond device can be remarkably improved. Diamond is adopted as the gate insulating layer, the gate insulating layer and the conductive channel layer are both diamond, the thermal expansion coefficient is the same, and thermal stress is reduced.

The application relates to the technical field of cable materials, in particular to an insulating cable material and a preparation method thereof. A large number of'sea-island' interface structures exist in a PP / SEBS blended material body, and charges generated by electrode injection and polarization are prone to accumulating at the'sea-island' interface, so that space charge accumulation is caused, and the voltage breakdown field strength of the material is reduced. Based on the above problems, the application provides an insulating cable material, wherein long-carbon-chain modified graphene is added in the material system; the long carbon chain makes the nano-graphene sheet layer structure not prone to agglomeration; the long carbon chain can also act as a 'bridge' to accelerate the migration speed of carriers in SEBS in all directions, so that the difference between the number of carriers reaching and leaving the'sea-island' interface in the polarization process of the PP / SEBS blended material is reduced, and the space charge accumulation phenomenon at the interface is effectively improved.

The application provides a high-frequency transformer functional insulating material of plasmonic orientation boron nitride and a preparation method and application thereof, and relates to the technical field of insulating materials. The functional insulating material is obtained by sequentially covering, from an inner layer to an outer layer, a thermosetting resin matrix layer, a silicon-rich transition layer, an oriented boron nitride sheet layer, a boron nitride gradient insulating layer and a densified surface layer on the surface of a metal conductor. The insulating material can realize heat diffusion enhancement, electric field distribution homogenization and space charge inhibition, and exhibits high breakdown strength, high local discharge starting voltage and good long-term insulating stability under high-frequency non-sinusoidal voltage, and is suitable for insulating reinforcement of the winding end, the outgoing line end and the core clamping piece area of a high-frequency transformer of a super-speed train, and has a good application prospect.

The invention discloses high-strength electrical epoxy resin and a preparation method thereof in the technical field of epoxy resin. The high-strength electrical epoxy resin comprises the following components in parts by weight: 30-50 parts of bisphenol F epoxy resin, 50-70 parts of bisphenol A epoxy resin, 15-25 parts of a functionalized epoxy monomer, 30-40 parts of a hyperbranched curing agent, 5-8 parts of a reactive diluent, 0.5-1 part of an antioxidant, 10-15 parts of aluminum hydroxide and 1-2 parts of a silane coupling reagent. By introducing the functionalized epoxy monomer and the hyperbranched curing agent, the technical effects of remarkably improving the tensile strength of the epoxy resin, improving the interfacial compatibility of the inorganic filler and the resin matrix, increasing the volume resistivity and reducing the dielectric loss are achieved.

The invention provides orthogonal-tetragonal multilayer heterostructure antiferroelectric ceramic and a preparation method thereof. Tetragonal phase antiferroelectric presintering powder is prepared, orthogonal phase antiferroelectric presintering powder is prepared, the tetragonal phase antiferroelectric presintering powder and the orthogonal phase antiferroelectric presintering powder are respectively subjected to secondary ball milling, drying and sieving and then subjected to tape casting treatment, and the antiferroelectric ceramic with the orthogonal-tetragonal multilayer heterostructure is obtained. A single-layer film A and a single-layer film B are obtained; and carrying out heterogeneous lamination temperature isostatic pressing treatment on the single-layer film A and the single-layer film B according to modes of AAAA, ABBA, BAAB, ABAB and BBBB to obtain the multi-layer heterostructure anti-ferroelectric ceramic, carrying out glue removal on the multi-layer heterostructure anti-ferroelectric ceramic, and calcining to obtain the orthogonal-tetragonal multi-layer heterostructure anti-ferroelectric ceramic. According to the multilayer heterostructure constructed by the invention, the breakdown field strength and the macroscopic polarization response of the material are synergistically improved through the interface blocking effect induced by the interlayer interface and the MWS interface polarization effect, so that the energy storage density is effectively improved.

This invention discloses a cross-linked polyethylene insulation material for medium-voltage DC cables and its preparation method. By weight, it comprises the following raw materials: 100-110 parts LDPE, 5-8 parts modified filler, 0.4-0.6 parts antioxidant, 0.2-0.3 parts cross-linking aid, and 0.4-0.7 parts initiator. The modified filler, prepared by a specific method, combined with an optimized cross-linking and antioxidant system, significantly improves the overall performance of the insulation material. This modified filler, through the synergistic effect of its deep trap energy levels in the core and the shallow trap energy levels of the outer organic molecules, increases the DC resistivity and breakdown field strength of the material. Simultaneously, the flexible long-chain structure grafted onto the filler surface improves its interfacial compatibility with the polyethylene matrix, giving the material excellent mechanical properties that meet the stringent requirements for long-term safe and stable operation of medium-voltage DC cables.

This invention discloses a polynorbornene imide insulating material, its preparation method, and its applications, belonging to the technical field of electrical insulation materials and their preparation. This invention solves the problem of poor insulation performance in existing polynorbornene imide dielectric films. This invention obtains FPNI by fluorinating polynorbornene imide (PNI), a polymer dielectric film with a wide bandgap and a high glass transition temperature organic rigid backbone. Furthermore, by doping FPNI with the wide bandgap organic molecule 4,4-dihydroxydicyclohexane (OH), not only is hydrogen bonding crosslinking between hydroxyl and fluorine atoms achieved, but the wide bandgap OH also brings higher electronic transition energy levels, resulting in a crosslinked polymer film with excellent insulation performance and a breakdown field strength of 619.53 MV / m.