196results about How to "Improve Microwave Performance" patented technology

The invention discloses a microwave medium ceramic material with a low-temperature sintering spinel structure and a preparation method thereof. The microwave medium ceramic material with the low-temperature sintering spinel structure contains 97-100 percent by weight of Li2MTi3O8 and 0-3 percent by weight of material with low melting point, wherein M is Zn or Mg; and the material with the low melting point is B2O3 or BaCu(B2O5) or V2O5. The material can be obtained by a solid-phase reaction. The microwave medium ceramic with a low-temperature sintering spinel structure (LTCC) has low sintering temperature (about 900DEG C) and excellent microwave performance: large dielectric constant (epsilon r), high Q*f value and small tau f; the microwave medium ceramic material does not react with Ag and can be co-fired by using pure Ag as an electrode; in addition, the invention can greatly reduce the manufacturing cost of a device, can be used for manufacturing a low-temperature cofiring ceramic system (LTCC), a multilayer medium resonator, a microwave antenna, a filter and other microwave devices.

The invention discloses a low temperature co-fired microwave dielectric ceramic material and a preparation method thereof. The ceramic material comprises a main powder material Li2ZnTi3O8, an auxiliary component TiO2 and low-melting-point LZB (Li2O-ZnO-BiO2) or LBS (Li2O-B2O3-SiO2) glass powder. The preparation method comprises the following steps of: adding TiO2 and the glass powder into the Li2ZnTi3O8 powder in a powder form; and then evenly mixing in a ball mill, drying, pelleting and sintering so as to obtain the ceramic material. In the invention, based on the Li2ZnTi3O8 powder as a reference, batching is carried out according to the proportions that the mass of the glass powder is 0.5-3wt% of that of Li2ZnTi3O8 and the mass of the TiO2 powder is 0-5wt% of that of Li2ZnTi3O8; and thematerial of the invention can be obtained by a traditional solid phase reaction method. The low temperature co-fired microwave dielectric ceramic material prepared by the method of the invention has low sintering temperature (about 875 DEG C) and good microwave dielectric property, and can be well co-fired with a Ag electrode; pure silver with high electricity conductivity and low cost is used asan electrode material, thus the manufacturing cost of a device can be greatly reduced; and the low temperature co-fired microwave dielectric ceramic material can be used for a low temperature co-fired ceramic (LTCC) system and manufacturing of microwave devices such as multilayer dielectric resonators, microwave antennas, filters and the like.

The invention discloses a Li2Zn3Ti4O12 microwave dielectric ceramic material and a low temperature sintering method thereof. The Li2Zn3Ti4O12 microwave dielectric ceramic material comprises 95% to 99.75% of Li2Zn3Ti4O12 and 0.25% to 5% of low melting point material by weight percent, wherein the low melting point material is one of H3BO3, BaCu(B2O5), V2O5 and Bi2O3. The method comprises the stepsof: firstly pre-calcining to synthesize a main powder body according to a molar ratio of Li2CO3: ZnO: TiO2=1:3:4; adding BaCu(B2O5), H3BO3, Bi2O3 or V2O5 to the main powder body; and granulating, tabletting and sintering. The prepared microwave dielectric ceramic material has low sintering temperature (about 900 DEG C), excellent microwave performance, large microwave constant (epsilon r), high Q*f value and small tau f, does not react with silver (Ag), and can be co-fired with pure silver as an electrode, largely reduce the manufacturing cost of a device, and be used for manufacturing microwave devices, such as low temperature co-fired ceramic (LTCC) system, multilayer dielectric resonators, microwave antennae, filters and the like.

The invention discloses a low-temperature co-fired Li2MgTi3O8 microwave dielectric ceramic material and a preparation method thereof. The material comprises a main powder material Li2MgTi3O8 and low-melting-point Li2O-MgO-B2O3 (LMB) glass powder. The glass powder is added into Li2MgTi3O8 powder in the form of powder and then the mixture is evenly mixed in a ball mill and is dried, granulated and fired to obtain the material. The proportions of components for preparing the material are determined by taking the Li2MgTi3O8 powder as a reference, wherein the weight of the glass powder accounts for 0.5-3 percent of the weight of Li2MgTi3O8 powder. The material can be obtained through the traditional solid-phase reaction synthesis method. The low-temperature co-fired microwave dielectric ceramic material prepared by adopting the preparation method has the advantages that the firing temperature is low (approximate 875 DEG C), the microwave dielectric performance is excellent, the dielectric constant (epsilon r) is large, the quality factor (Q-f) is high, the resonant frequency-temperature factor (tf) is close to zero, the effect of co-firing with an Ag electrode is good, high-conductivity low-cost pure silver can be used as an electrode material, the manufacturing cost of devices can be greatly reduced, and the low-temperature co-fired microwave dielectric ceramic material can be used for manufacturing microwave devices such as low-temperature co-fired ceramic (LTCC) systems, multilayer dielectric resonators, microwave antennas and filters.

The invention discloses a temperature-stable low-cost microwave dielectric ceramic material and a preparation method thereof. The microwave dielectric ceramic material has the following chemical composition formula of (1-x)Li2ZnTi3O8+xM, wherein x is more than or equal to 0.025 and less than or equal to 0.1, and M is TiO2 or CaTiO3. The preparation method comprises the following steps of: taking LiCO3, ZnO and TiO2 of which the purity is more than or equal to 99% as the main raw material at the following molar ratio: 1 mole of Li2CO3, 1 mole of ZnO and 3 moles of TiO2; pre-calcining to synthesize the main powder body of Li2ZnTi3O8; and then, adding TiO2 or CaTiO3 in the main powder body to regulate the temperature coefficient of resonance frequency of the main powder body so as to obtain the microwave dielectric material of which the dielectric constant, the Q*f value and the temperature coefficient of resonance frequency approach to zero. The sintering temperature of the microwave dielectric ceramic prepared with the preparation method is lower than 1100DEG C, the dielectric constant is 26-31, the Q*f value is 40000-70000GHz, and the temperature coefficient (tau f) of resonance frequency is small. The temperature-stable low-cost microwave dielectric ceramic material can be used for manufacturing microwave devices, such as resonators, antennae, filters and the like.

The present invention discloses a T-gate and N-surface GaN/AlGaN fin-type high electron mobility transistor. The problems are mainly solved that the maximum oscillating frequency of a current microwave power device is small, the ohmic contact resistor is large and the short channel effect is severe. The transistor comprises from down to up: a substrate (1), a GaN buffer layer (2), a ALGaN barrier layer (3), a GaN channel layer (4), a gate medium layer (5), a passivation layer (6), a source gate electrode and a drain gate electrode. The buffer layer and the channel layer employ N-surface GaN materials; the GaN channel layer and the ALGaN barrier layer form GaN/AlGaN heterojunction; the gate electrode employs T-type gate and is wrapped at two sides and the upper portion of the GaN/AlGaN heterojunction to form a three-dimensional gate structure. The T-gate and N-surface GaN/AlGaN fin-type high electron mobility transistor has good gate-control capability, small resistor and the maximum oscillating frequency, and is able to be a microwave power device with the small size.

The invention discloses a novel high-power microwave vacuum ceramic window which comprises two cone-shaped window bodies which are symmetrically arranged in a left-and-right mode and a ceramic piece in a middle position. A circular waveguide window frame is arranged on the outer side of the ceramic piece, and the ceramic piece is arranged along the radial direction of the window frame. An outer water sleeve is sleeved on the outer side of the window frame, and a water inlet connector and a water outlet connector are welded in the outer water sleeve. The left and the right ends of the window frame and the outer water sleeve are respectively assembled and connected with round waveguides of the cone-shaped window bodies of the left side and the right side of the ceramic window. Rectangular waveguides of the cone-shaped window bodies are connected with flanges, a fire striking detecting device is arranged on the right window body, the rectangular waveguides are gradually transformed to be the round waveguides through the left window body, and the round waveguides are gradually transformed to be the rectangular waveguides through the right cone-shaped window body. The novel high-power microwave vacuum ceramic window has the advantages of being good in microwave performance, high in vacuum tightness, high in safety, high in reliability, not rigorous for machining requirements, capable of achieving one-off vacuum welding and the like, and is suitable for general application of vacuum systems.

The invention discloses a silicon-based multichannel TR assembly. The silicon-based multichannel TR assembly, in the structure, comprises a multilayer silicon-based substrate 1 with signal transmission, passive element integration and chip carrier, a microwave single chip integrated circuit and a digital integrated circuit 2 for realizing various specific functions of the TR assembly, and a high-resistivity silicon cap 3 whose top is used for sealing and protection, wherein the multilayer silicon-based substrate at least comprises three layers of metal wiring, metal adopts a Cu material, the silicon-based surface uses multiple layers of dielectric materials with a low dielectric constant for isolation between metal layers and surface passivation protection, multiple through silicon vias (TSV) are made inside the silicon-based substrate as cooling channels for microwave chip grounding and inner high-power consumption elements and key parts for microwave signal vertical transmission; and external control and microwave interfaces are arranged around the silicon-based material. The silicon-based multichannel TR assembly and the design method have the advantages that a multichannel TR assembly within 40 GHz can be realized, the microwave performance is excellent, and miniaturization and low cost of the TR assembly can be realized.

The invention relates to a low temperature co-fired ceramic microwave dielectric material and a method for preparing the same. The material proportion is as follows: (1-x)Ba5+y(Nb1-kMnk)4O15-xBa1+zNb2O6 is added with a burning auxiliary agent which is 0.3 to 2.8 weight percent of the total materials, wherein the burning auxiliary agent is boron oxide, the boron oxide and zinc oxide, the boron oxide and copper oxide, the boron oxide and barium oxide, or the barium oxide, the boron oxide and the copper oxide; and x is more than or equal to 0 and less than 1, y is more than 0 and less than or equal to 0.3, z is more than or equal to 0 and less than or equal to 0.3, and k is more than or equal to 0 and less than or equal to 0.1. With the addition of Ba1+zNb2O6 and small amount of low melting point oxide, the sintering temperature of the low temperature co-fired ceramic microwave dielectric material is lowered to about 900 DEG C to obtain excellent microwave dielectric properties: the dielectric constant is between 39 and 42, the microwave characteristic is more than 15,000, and the resonant frequency temperature coefficient is about 30; and the material can be applied to the manufactures of microwave devices such as low temperature co-fired ceramic systems, multi-layer dielectric resonators, microwave antennas, filters.

A microwave power transducer of two-ends heating type is prepared as using GaAs as substrate, arranging a layer of AIGaAs film on said substrate, setting thermoelectric stack formed by a group of series-connected GaAs/AuGe thermocouple on AIGaAs film, using coplanar waveguide A on GaAs substrate as input transmission line of microwave signal to be measured and connecting coplanar waveguide with two parallel-connected DC heating resistances.

The invention belongs to the field of radio frequency MEMS, in particular to a K-type single-pole four-throw radio frequency MEMS switch. The K-type single-pole four-throw radio frequency MEMS switchis mainly composed of a substrate, a microwave transmission line, a driving electrode, an upper electrode, a lower electrode, a fixed anchor and contacts. The microwave transmission line and the driving electrode are arranged on the substrate. The upper electrode is of a straight plate structure, and the lower electrode is a double contact with an elastic beam. The microwave transmission line usesa power divider of a K-type structure to divide the input signal power into four equal signals for output. From the point of view of microwave transmission, the K-type structure is more efficient, and improves the smooth flow of current and the transmission performance between branches of the switch. The designed single-pole four-throw switch has smaller insertion loss and better isolation. In addition, release holes in cantilever beams reduce the stress on the whole cantilever beams and greatly improves the isolation of the switch.

The invention discloses a silicon-based suspended microstrip line structure and a manufacturing method therefor, and mainly solves problems in the prior art that the transmission loss of terahertz waves is large and a terahertz suspended microstrip line is low in machining precision. The structure comprises a suspended microstrip line (1), a silicon substrate (4), an air cavity (5) and a metal floor layer (6), wherein the silicon substrate (4) comprises an upper silicon substrate (41) and a lower silicon substrate (42). The metal floor layer (6) is located between the upper silicon substrate (41) and the lower silicon substrate (42). The microstrip line (1) is prepared on a BCB (benzocyclobutene) photoresist layer (2), and a silicon nitride layer (3) grows between the BCB photoresist layer (2) and the upper silicon substrate (41). The air cavity (5) is disposed in the upper silicon substrate (41) in an etched manner, and is located exactly below the microstrip line (1). The structure is low in loss, is simple in structure, is easy to machine, and can be used for the active and passive circuits at the terahertz band.

The invention provides a microwave attenuator which comprises a substrate, and a coplanar waveguide (1), a first absorption resistor (21), a second absorption resistor (22), a first micro-mechanical switch (31) and a second micro-mechanical switch (32) which are arranged on the substrate, wherein the coplanar waveguide (1) comprises a coplanar waveguide signal wire (11), and a first coplanar waveguide earth wire (1a) and a second coplanar waveguide earth wire (1b) which are arranged symmetrically with respect to the coplanar waveguide signal wire (11); and one end of the first absorption resistor (21) is connected with the coplanar waveguide earth wire (1a), the other end of the first absorption resistor (21) is disconnected with the coplanar waveguide signal wire (11), and the first micro-mechanical switch (31) is placed in the disconnection position. The microwave attenuator controls the access of the absorption resistors by switching on or off the micro-mechanical switches, thereby realizing reconfiguration of multiple attenuations of the microwave attenuator, namely realizing reconfiguration of the attenuator structure.

The invention discloses an ultralow-temperature-sintered composite microwave dielectric ceramic material and a preparation method thereof. The formula of the ceramic material is (Ag0.5Bi0.5)(MoxW1-x)O4, wherein 0.3<=x<=0.7. The ultralow-temperature-sintered composite microwave dielectric ceramic material has the characteristics of finely adjustable relative dielectric constant (32.2-34.5), favorable microwave behavior microwave dielectric ceramics (Qf=11500GHz-12000GHz), adjustable temperature coefficient of resonance frequency (-32ppm/DEG C to +19ppm/DEG C) and simple chemical composition. By adopting the solid-phase reaction sintering method, the invention is simple in technological operation, environment-friendly and suitable for industrial production.

The invention discloses a warping plate type intelligent detection microwave power sensor. The sensor comprises a substrate, a first coplanar waveguide ground wire, a coplanar waveguide signal wire, a second coplanar waveguide ground wire, a sensing electrode, a driving electrode, an SOC circuit and a warping plate type double-end cantilever beam, wherein the substrate, the first coplanar waveguide ground wire, the coplanar waveguide signal wire, the second coplanar waveguide ground wire, the sensing electrode, the driving electrode and the SOC circuit are sequentially arranged on the substrate, and the warping plate type double-end cantilever beam is arranged on the coplanar waveguide ground wire and is perpendicular to coplanar waveguide. The lower side of the middle of the warping plate type double-end cantilever beam is connected with the second coplanar waveguide ground wire, one end of the warping plate type double-end cantilever beam is arranged above the coplanar waveguide signal wire in a suspension mode, the other end of the warping plate type double-end cantilever beam is arranged above the sensing electrode and the driving electrode, and the SOC circuit is respectively connected with the second coplanar waveguide ground wire, the sensing electrode and the driving electrode through wires. The warping plate type intelligent detection microwave power sensor reduces influence of a small power sensing structure on a device reflective coefficient to the largest extent, ensures good transmission performance of a microwave signal, and meanwhile can improve flexibility and intellectualization.