38results about How to "Lower Frequency Temperature Coefficient" patented technology

A TE01 mode dielectric filter comprises a cavity, a cover plate, dielectric resonators, T-shaped coupling rods, tuning screws, SMA electric connectors and fastening screws. The TE01 mode dielectric filter is characterized in that cross couplings of the filter are all positive, and a main coupling is provided with two negative couplings positioned between the dielectric resonators R1 and R2 and between the dielectric resonators R6 and R7 respectively by the aid of the novel T-shaped coupling rods. Due to the fact that all cross couplings of the filter are positive and implemented through coupling holes, compared with a traditional dielectric filter with negative cross couplings implemented through probes, the TE01 mode dielectric filter has the advantages that introduced parasitic couplings are small, introducing redundant cross couplings for overcoming influences of the parasitic couplings is not needed, and reliability of the filter is improved. In addition, the novel T-shaped coupling rods are low in chromatic dispersion and simple in processing, fine tuning of coupling can be realized by the aid of the tuning screws, repeatedly demounting the cover for altering the sizes of the coupling rods during debugging of the filter is avoided, and accordingly debugging workload is reduced.

The invention provides a ceramic material and a preparation method thereof. The ceramic material has the general formula shown in formula I. The invention provides a polytetrafluoroethylene-ceramic composite material, which is prepared from ceramic powder and polytetrafluoroethylene, and the ceramic powder has the general formula shown in formula I. The invention provides a preparation method of a polytetrafluoroethylene-ceramic composite material, comprising: under the action of a silane coupling agent, mixing ceramic powder, polytetrafluoroethylene and a demulsifier to obtain a polytetrafluoroethylene-ceramic Composite material, the demulsifier includes alcohol compound or ether compound; the ceramic powder has the general formula shown in formula I. The invention provides a substrate, which is prepared from the above-mentioned polytetrafluoroethylene-ceramic composite material. The polytetrafluoroethylene-ceramic composite material provided by the invention has higher dielectric constant, lower loss, higher quality factor and higher thermal conductivity. xLi2TiO3‑(1‑x)ZnNb2O6 Formula I.

A novel microwave dielectric ceramic and a preparation method of the novel microwave dielectric ceramic belong to a microwave dielectric material and the technical field of microwave dielectric material manufacture. The microwave dielectric ceramic is composed of K, Dy, Ho, Er, Yb, Lu and Ti in modes of carbonate and oxide, a chemical formula of the microwave dielectric ceramic is K0.5Re4.5Ti4O15, and the Re is equal to the Dy, Ho, Er, Yb, Lu in the formula. The novel microwave dielectric ceramic provides a new material containing a rare earth microwave dielectric and expands selecting ranges of microwave dielectric application materials. A matched process is provided for the microwave dielectric ceramic, and the microwave dielectric ceramic with a good ceramic forming ratio is obtained.

A B-substituted BNT microwave dielectric ceramic material and its preparation method belong to the technical field of a functional material. The general chemical formula of the microwave dielectric ceramic material is Ba3.75Nd9.5Ti18-y(M,N)yO54, wherein y is less than or equal to 2.5 and greater than or equal to 0.6; the microwave dielectric ceramic material is prepared by steps of: burdening BaO, Nd2O3, TiO2, oxides of metallic elements M and N according to mole ratio of the general chemical formula, carrying out ball-milling, presintering and sintering; an oxide of the element M is Nb2O5; and an oxide of the element N is one or more compounds selected from Al2O3, MgO, ZnO, Co2O3 and NiO. According to the invention, simultaneous substitution of high and low valence elements is carried out in the B position of Ba6-3xNd8+2xTi18O54. The microwave dielectric ceramic material prepared by a one-step synthesis process has high dielectric constant, low loss characteristic and low frequency-temperature coefficient, can meet requirements in the microwave communication industry, and is especially suitable for manufacturing of RFID tags.

The invention provides a high-mechanical-quality-factor elastic alloy and a manufacturing method of the high-mechanical-quality-factor elastic alloy and belongs to the technical field of elastic alloy. The high-mechanical-quality-factor elastic alloy comprises, by weight, not larger than 0.005% of C, 19.10-21.50% of Ni, 9.00-12.00% of Co, 3.00-6.00% of Mo, 0.40-1.20% of Ti and the balance Fe and inevitable impurities. The high-mechanical-quality-factor elastic alloy is smelted by means of a vacuum induction furnace and is forged to be a square billet with the edge being 60-90mm long, and thenthe square billet is hot-rolled into rod materials. The finished rod materials are processed through two steps of solution treatment at the temperatures of 1050-1150 DEG C and 810-860 DEG C correspondingly, the finished rod materials are aged at the temperature of 480-620 DEG C for 2-8 h, and then the finished rod materials are air-cooled to the indoor temperature. The high-mechanical-quality-factor elastic alloy has the advantages of being high in mechanical quality factor and low in frequency-temperature coefficient and being applied to inertial navigation components, harmonic oscillators and other high-precision elements.

The invention discloses a forming method of an MEMS (Micro-Electro-Mechanical System) device. The method comprises the following steps: providing a substrate, wherein CMOS (Complementary Metal Oxide Semiconductor) devices are formed in the substrate; forming a sacrificial layer on the substrate; forming first through holes in the sacrificial layer, wherein the first through holes are positioned in the CMOS devices; forming a SiGe layer on the sacrificial layer and in the first through holes, wherein the first through holes are fully filled with the SiGe layer; generating a silicon oxide layer on the SiGe layer through a thermal oxide growth process; and after the silicon oxide layer is formed, removing the sacrificial layer. SiO<2> generated by the thermal oxide growth process is combined with SiGe by bonding, so that an interface characteristic between the silicon oxide layer and the SiGe layer can be enhanced, the bonding force between the silicon oxide layer and the SiGe layer is enhanced, and the problem of peeling is solved in comparison to SiO<2> formed by chemical vapor deposition.

The present invention provides a high dielectric microwave dielectric ceramic material, the general chemical formula of the material is (Ca0.35Li0.25Nd0.35)(Ti1-xDx)O3, wherein 0.01≤x≤0.05, the composition of D is VW, and V represents the valence state Higher than tetravalent Ta, W represents a single or multiple elements whose valence is lower than tetravalent and the average ionic radius is close to Ti4+, V and W can be substituted simultaneously or separately; the present invention also provides a high dielectric microwave dielectric ceramic The preparation method of the material comprises the steps of: batching, ball milling, drying and sieving, pre-calcination, granulation, compression molding, and sintering; the material prepared by the invention has a high dielectric constant and a relatively high Q×f value, and can be adjusted Frequency temperature coefficient. The formula does not contain volatile toxic metals such as Pb and Cd, and has stable performance, which can meet the application requirements of modern microwave devices. The raw materials are abundantly supplied in China and the price is relatively low, which makes it possible to reduce the cost of high-performance microwave ceramics.

The invention discloses a low temperature sintering coke verd antique high frequency / microwave medium ceramics. The expression of the ceramics is Bi3xM2-3x)(ZnxNb2-x)O7, and M is Zn2+, Ca2+ or Cd2+, or Sr2+, and 0.5<=x<=0.64. The invention has the following feature: high dielectric constant, low medium consumption, wide covering range of temperature coefficient dielectric constant, low sintering temperature, simple technology, etc.

The invention discloses microwave dielectric ceramics and a preparation process thereof, belonging to the technical field of microwave dielectric materials and manufacture thereof. The microwave dielectric ceramics comprises carbonate, oxide and Na, Gd, Dy, Er, Lu and Ti organic matters, and has a chemical formula of Na0.5Re4.5Ti4O15, wherein Re=Gd, Dy, Er and Lu. The invention provides a novel rare-earth-containing microwave dielectric material, and the selection range of a microwave dielectric application material is enlarged; and aiming at the microwave dielectric ceramics, the invention provides a novel matched process, namely, the microwave dielectric ceramics with better ceramic formation is obtained by combination of a process of preparing a powder material by adopting a sol-gel process and a process of preparing the ceramics by adopting a solid-phase reaction process.

The invention belongs to the technical field of microwave dielectric ceramic materials, and in particular relates to a barium niobate system microwave dielectric ceramic material. The barium niobate system microwave dielectric ceramic material of the present invention, with BaCO 3 , Nb 2 o 5 , ZnO, CoO and NiO as raw materials to synthesize the main sintered block, and SiO 2 , BaO, CaO, B 2 o 3 , Li 2 O is used as a raw material to synthesize low-melting glass powder, and then the main sinter and the low-melting glass powder are mixed and dispersed to obtain the required barium niobate system microwave dielectric ceramic material. The dielectric constant of the microwave dielectric ceramic material reaches 33-36, f*Q>80000 at 25°C, and the frequency temperature coefficient calculated by testing the resonant frequencies f of -40°C, 25°C, and 110°C is low, only ‑5~5ppm / ℃, its performance meets the requirements of microwave dielectric ceramic devices; at the same time, the material also has good dielectric properties in the millimeter wave frequency band; it can be used to produce ceramic devices such as filters and resonators.