40results about How to "Good quality factor" patented technology

The invention discloses a thin film piezoelectric sonic sensor. The thin film piezoelectric sonic sensor comprises a substrate layer, a ground electrode layer and a piezoelectric layer which are arranged in a laminated mode, and one or more transducers are arranged on the side, away from the ground electrode layer, of the piezoelectric layer; and photonic crystals at least formed in the piezoelectric layer are correspondingly arranged on the two sides of the transducers, and the resonant frequency of the thin film piezoelectric sonic sensor is located in band gaps of the photonic crystals. According to the thin film piezoelectric sonic sensor, the photonic crystals are at least arranged on the piezoelectric layer, the mechanical vibration stability of the piezoelectric layer is improved, the sonic wave reflectivity is improved, the energy loss of sonic wave transmission is lowered, and the quality factor of the sensor is improved. The invention discloses a photonic crystal. The photonic crystal comprises a matrix and a scatterer formed on the matrix, the matrix is formed by at least two media layers in a laminated mode, and materials of any one of the media layers are different from those of other media layers. According to the photonic crystal, the sonic wave energy loss can be effectively reduced, and the quality factor of the sensor can be effectively improved when the photonic crystal is applied to the thin film piezoelectric sonic sensor.

The invention provides a bulk acoustic wave resonator, a manufacturing method thereof, a filter and a radio frequency communication system. A bottom electrode concave part and a top electrode concavepart formed on the periphery of a piezoelectric resonance layer and suspended above a cavity can prevent transverse waves generated by the piezoelectric resonance layer from being transmitted to the periphery of the cavity and reflect the transverse waves back to an effective working area, so that sound wave loss is reduced, the quality factor of the resonator is improved, and finally the performance of a device can be improved. Furthermore, the overlapping parts of a bottom electrode overlapping part and the cavity and the overlapping parts of a top electrode overlapping part and the cavity are suspended, and the bottom electrode overlapping part and the top electrode overlapping part are mutually staggered, so that a parasitic parameter can be greatly reduced, the problems of electric leakage, short circuit and the like can be avoided, and the reliability of the device can be improved.

The invention belongs to the field of preparation of air filtering materials, relates to a polyimide / polyurethane aerogel film air filtering material as well as preparation and application thereof, and particularly discloses a PI / TPU aerogel film with mesopores and macropores in a certain proportion, which is obtained by introducing polyurethane (TPU) to adjust a pore structure during preparation of PI aerogel. The filter material has the advantages of high filter efficiency, low piezoresistance and high quality factor, is relatively simple to prepare, and has a good industrial prospect.

The invention relates to a preferred structure of a film bulk acoustic resonator with a high quality factor. The structure comprises a substrate with a groove in the upper surface, a bottom electrodelayer located above the substrate and a piezoelectric layer, and is characterized by further comprising a top electrode layer with a special-shaped air bridge structure, and an acoustic springback structure capable of playing a role in springback of transverse acoustic waves is arranged in the air bridge structure; the sound springback structure is a convex or trapezoidal polyhedron opposite to abridge cavity of the special-shaped air bridge structure and is horizontally arranged in an area above the bridge cavity of the special-shaped air bridge structure. The top end surface of the sound springback structure is embedded and clung to a bridge cavity upward top surface groove of the special-shaped air bridge structure; an air gap is reserved between the bottom end face of the sound springback structure and the suspended structure in the area below the bridge cavity of the special-shaped air bridge structure, and the left side face and the right side face of the sound springback structure are embedded into and tightly attached to the grooves in the adjacent inner side faces of the bridge cavity supporting structure of the special-shaped air bridge structure respectively. The quality factor of the film bulk acoustic resonator can be remarkably improved.

The invention provides a bulk acoustic wave resonator, a manufacturing method thereof, a filter and a radio frequency communication system. A top electrode concave part formed on the periphery of a piezoelectric resonance layer and suspended above a cavity can prevent transverse waves generated by the piezoelectric resonance layer from being transmitted to the periphery of the cavity and reflect the transverse waves back to an effective working area, so that the sound wave loss is reduced, the quality factor of the resonator is improved, and finally, the performance of a device can be improved. Furthermore, the overlapping parts of a bottom electrode overlapping part and the cavity and the overlapping parts of a top electrode overlapping part and the cavity are suspended, and the bottom electrode overlapping part and the top electrode overlapping part are mutually staggered, so that a parasitic parameter can be greatly reduced, the problems of electric leakage, short circuit and the like can be avoided, and the reliability of the device can be improved.

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.

The invention discloses a single-tuned filter and an optimal quality factor calculation method thereof. The single-tuned filter mainly comprises a capacitor C, an inductor L and a resistor R which are sequentially connected in series, wherein the other end of the capacitor C is connected with an alternating current voltage line; and the other end of the resistor R is grounded. The method comprises the following steps of: A, calculating the maximum equivalent frequency offset of a system; B, determining a maximum impedance angle of the system; and C, calculating an optimal quality factor of the filter. By the single-tuned filter and the method, the terminal voltage of the filter can be ensured to have a minimum value at characteristic frequency when the system has the maximum impedance angle, so filtering effects and system stability are ensured.

The invention relates to a preferred structure of a high quality factor thin film bulk acoustic resonator, comprising a substrate with a groove on the upper surface, a bottom electrode layer above the substrate, and a piezoelectric layer, and is characterized in that it also includes a The top electrode layer of the special-shaped air bridge structure, which is equipped with an acoustic rebound structure that can rebound the transverse sound wave; the acoustic rebound structure is a convex or opposite bridge cavity of the special-shaped air bridge structure. The trapezoidal polyhedron is arranged horizontally in the area above the bridge cavity of the special-shaped air bridge structure. The top surface of the acoustic rebound structure is embedded and closely attached to the groove on the top surface of the bridge cavity of the special-shaped air bridge structure. The acoustic rebound structure There is an air gap between the bottom end surface and the suspension structure in the area below the bridge cavity of the special-shaped air bridge structure. The left and right sides of the acoustic rebound structure are respectively embedded and adjacent to the bridge cavity support structure of the special-shaped air bridge structure. The grooves on the inner side fit snugly. The invention can significantly improve the quality factor of the film bulk acoustic wave resonator.

The invention discloses a method for manufacturing a stacked inductor and a device obtained therefrom, wherein the method comprises the steps of: coating a first photoresist, performing a photolithography process on the bottom of an enhanced gate and the bottom of a first metal layer of the inductor; coating a first photoresist Two photoresist, perform photolithography process on the top of the enhanced gate and the top of the first metal layer of the inductor; deposit metal to form the enhanced gate and the first metal layer of the inductor; passivate the enhanced gate and the first metal layer of the inductor process, forming a first passivation layer; etching the depletion gate and the first passivation layer of nitride connected to the second metal layer of the inductor; coating a third photoresist to perform depletion gate and photolithography process of the second metal layer of the inductor; depositing metal to form the depletion gate and the second metal layer of the inductor. The inductance of the spiral stack shape prepared by this scheme has a better quality factor under high frequency conditions and also has a larger inductance value. And the process is carried out simultaneously with the existing transistor process without increasing the process cost.

A thin film piezoelectric sonic sensor, comprising: a substrate layer (2), a ground electrode layer (3), and a piezoelectric layer (4) which are stacked. At least one transducer (5) is provided on the side of the piezoelectric layer (4) distant from the ground electrode layer (3); phononic crystals (1) at least formed in the piezoelectric layer (4) are correspondingly provided on the two sides of the transducer (5), and the resonant frequency of the thin film piezoelectric sonic sensor is located in a band gap of the phononic crystals (1). According to the thin film piezoelectric sonic sensor, the phononic crystals (1) are at least provided on the piezoelectric layer (4), the mechanical vibration stability of the piezoelectric layer (4) is improved, the sonic wave reflectivity is improved, the energy loss of sonic wave transmission is lowered, and the quality factor of the sensor is improved. A phononic crystal (1) comprises a matrix and a scatterer formed on the matrix; the matrix is formed by at least two stacked dielectric layers; materials of any one of the dielectric layers are different from those of other dielectric layers. The phononic crystal (1) can effectively reduce the sonic wave energy loss, and effectively improve the quality factor of the sensor when the phononic crystal is applied to the thin film piezoelectric sonic sensor.

The invention discloses a low-permittivity dielectric material for a single-cavity filter and a preparation method thereof. The structure of the low-permittivity dielectric material of the single-cavity filter is (1-z / 2)Mg 2 SiO 4 -(z / 2)M 2 SiO 4 -mCa （x / 2） ln (2 / 3‑x / 3) TiO 3 ‑ySnO 2 ‑(0.05~0.15)wt%AF. Preparation method of low dielectric constant dielectric material for single cavity filter, including Ca （x / 2） ln (2 / 3‑x / 3) TiO 3 Pre-preparation of crystalline phases, batching, primary grinding, spray drying, sintering, secondary grinding and spray granulation. According to the above content, the present invention proposes a low-permittivity dielectric material for a single-cavity filter and a preparation method thereof, one of the purposes of which is to provide a low-permittivity dielectric material with high quality factor and high flexural strength; The second is to provide a preparation method with simple preparation, easy-to-obtain raw materials, large-scale production and cost disclosure.

The invention belongs to the technical field of microwave dielectric ceramics, and particularly relates to a low-dielectric microwave dielectric ceramic material and an LTCC material thereof. A compound with a chemical general formula of Ca2RE8Si6O26 (wherein RE is selected from the group consisting of Nd, Sm and Er) is used for preparing the microwave dielectric ceramic material, and the LTCC material is further prepared. The ceramic material has a low relative dielectric constant (wherein Epsilon r is in a range of 13.4-14.0), an excellent quality factor (wherein the value of Q*f is in a range of 16300-18600 GHz) and a relatively wide sintering temperature (1350-1400 DEG C); meanwhile, the microwave dielectric ceramic has a negative resonant frequency temperature coefficient (wherein Tauf is no less than -38.1 ppm / DEG C and no more than -17.8 ppm / DEG C). The sintering temperature of the microwave dielectric ceramic material can be reduced to 950 DEG C or below after a certain amountof a sintering aid, namely CaO-La2O3-B2O3-SiO2 glass is added, and the microwave dielectric ceramic can be used as an LTCC material.

The present invention provides a bulk acoustic wave resonator, a manufacturing method thereof, a filter, and a radio frequency communication system. The raised portion of the bottom electrode and the raised portion of the top electrode formed on the periphery of the piezoelectric resonant layer and suspended above the cavity can block The shear wave generated by the piezoelectric resonant layer is transmitted to the periphery of the cavity, and the shear wave is reflected back to the effective working area, thereby reducing and reducing the acoustic wave loss, improving the quality factor of the resonator, and finally improving the performance of the device. Furthermore, the overlapping parts of the bottom electrode lap and the top electrode lap and the cavity are all suspended, and the bottom electrode lap and the top electrode lap are staggered from each other, which can greatly reduce parasitic parameters and avoid leakage, Short circuit and other problems can improve device reliability.

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 provides a winding method of a braided coil, belongs to the technical field of the magnetic field coupling type wireless electric energy transmission, and especially relates to a windingmethod of the braided coil. The problem that the quality factor is reduced when the eddy loop is formed between the coil turns, the inter-turn proximity effect is large, the coil AC internal resistance is large, and the working efficiency is high in the magnetic coupling type wireless electric energy transmission system is solved, and the Litz wire is used for winding. The winding method is mainly used for winding the braided coil of the magnetic field coupling type wireless electric energy transmission system.

Microwave dielectric ceramics with low loss and low frequency temperature coefficient and a preparation method thereof belong to the field of microwave dielectric materials and their manufacturing technology. The ratio of elements Ba, Eu, Nd and Ti contained in the microwave dielectric ceramics satisfies the chemical formula Ba6-3x(Eu1- y, Ndy)8+2xTi18O54, where x=0-1 and y=0.2-0.8; the microwave dielectric ceramic is made from barium carbonate, neodymium oxide, europium oxide and butyl titanate as main raw materials. The present invention provides a formula for a new microwave medium material containing rare earth, which expands the selection range of microwave medium application materials; and provides a reasonable new process for the material of the present invention, that is, the preparation of powder and solid-phase reaction by sol-gel method Combining the method to prepare ceramics, the microwave dielectric ceramics have a good quality factor, a low frequency temperature coefficient, and at the same time reduce the sintering temperature, thereby reducing the energy consumption of material preparation.