摘要:
A surface acoustic wave device is manufactured by directly or indirectly bonding a lid to a substrate having a surface acoustic wave element to seal the element under the lid. The lid is made of at least one material selected from the group comprising lithium niobate, lithium tantalete, lithium borate, glass and quartz. The substrate is made of at least one material selected from the group comprising quartz, lithium niobate, lithium tantalete and lithium borate.
摘要:
Integrated circuits utilizing piezoelectric elements can be advantageously constructed by bonding elements together via direct bonds. Such integrated circuits include an electro-acoustic hybrid integrated circuit such as a voltage controlled oscillator wherein a semiconductor substrate having an active element is bonded through direct bonding to a surface acoustic wave resonator or a quartz oscillator as an electro-acoustic element. A quartz device can also be provided which includes a quartz plate, excitation electrodes on opposite surfaces, and a holding member made of a material having a thermal expansion coefficient substantially equal to that of the quartz plate. The holding member is connected to the quartz plate by direct bonding without using any adhesives. Because the thermal expansion coefficients of the quartz plate and the holding member are equal, no thermal stress occurs in the bonding area. As a result, virtually no stress is applied to the quartz plate and the frequency-temperature characteristic can be improved. A piezoelectric filter according to the invention includes an oscillatory piezoelectric plate made of quartz, lithium tantalate, lithium niobate or lithium borate and having an oscillatory portion; a glass plate to which the piezoelectric plate is directly bonded; and first and second oscillatory electrode members which are provided on opposite faces of the oscillatory portion, respectively, such that at least one of the oscillatory electrode members is divided into a plurality of counter electrodes.
摘要:
A piezoelectric acoustic wave device includes a substrate and a piezoelectric plate. The piezoelectric plate includes a resonating part, and has a top electrode at least on the top surface of the resonating part. The substrate and the piezoelectric plate are directly bonded at an area where they are in contact with each other by a chemical bond such as a covalent bond and an ionic bond. A depression is formed in at least one of the substrate and the piezoelectric plate. The method of manufacturing the piezoelectric acoustic wave device includes the steps of forming a depression in at least one of the substrate and the piezoelectric plate, filling the depression with an intermediate support layer, cleaning the surfaces of the substrate and the piezoelectric plate to directly bond to each other by a chemical bond, forming electrodes, and removing the intermediate support layer.
摘要:
Integrated circuits utilizing piezoelectric elements can be advantageously constructed by bonding elements together via direct bonds. Such integrated circuits include an electro-acoustic hybrid integrated circuit such as a voltage controlled oscillator wherein a semiconductor substrate having an active element is bonded through direct bonding to a surface acoustic wave resonator or a quartz oscillator as an electro-acoustic element. A quartz device can also be provided which includes a quartz plate, excitation electrodes on opposite surfaces, and a holding member made of a material having a thermal expansion coefficient substantially equal to that of the quartz plate. The holding member is connected to the quartz plate by direct bonding without using any adhesives. Because the thermal expansion coefficients of the quartz plate and the holding member are equal, no thermal stress occurs in the bonding area. As a result, virtually no stress is applied to the quartz plate and the frequency-temperature characteristic can be improved. A piezoelectric filter according to the invention includes an oscillatory piezoelectric plate made of quartz, lithium tantalate, lithium niobate or lithium borate and having an oscillatory portion; a glass plate to which the piezoelectric plate is directly bonded; and first and second oscillatory electrode members which are provided on opposite faces of the oscillatory portion, respectively, such that at least one of the oscillatory electrode members is divided into a plurality of counter electrodes.
摘要:
The following steps are performed when processing electronic components such as piezoelectric devices. At Step 1 inter-atom bond is created between a functional member such as a quartz crystal plate and a first substrate, and the functional member and the quartz crystal plate are directly joined together. At Step 2, the functional member and a second substrate are fixed together with an adhesive agent or by a direct bond. At Step 3, the first substrate is removed chemically or mechanically, with said functional member and said second substrate still being joined together. A step of polishing said functional member for the adjustment of thickness thereof may be done between Step 1 and Step 2. For example, a silicon dioxide thin film may be provided between the functional member and the first substrate. Since no adhesive layer exists between the functional member and the first substrate, this improves the degree of plane of the functional member when joined to the first substrate. Therefore, functional member thickness accuracy becomes extremely high and mass productivity is also improved.
摘要:
A balanced-type surface acoustic wave filter is provided which can attain a balanced-type of high frequency circuit without connecting a balance-unbalanced conversion circuit. A substrate of tantalic acid lithium substrate with 36 degrees rotation, Y cut, and X propagation is used, and aluminium is used for electrode to form resonators. Then, two resonators in a serial arm and two resonators in a parallel arm are connected in the form of symmetry and lattice to form a balanced-type surface acoustic wave filter. In this configuration, antiresonance frequency in the serial arms and resonance frequency in the parallel arms are substantially equal to each other.
摘要:
In a surface acoustic wave (SAW) filter, on a 36.degree. Y-cut X-propagation lithium tantalate substrate, series branch SAW resonators, which are connected in series between an input terminal and an output terminal, and parallel branch SAW resonators, which are connected between respective pairs of the series branch resonators by wirings and which are grounded, are provided. Two series branch resonators and one parallel branch resonator are connected in a T shape, so as to form a fundamental unit. In the SAW filter, three fundamental units are serially connected. An interdigital transducer (IDT) included in each resonator is made of a metal film containing aluminum as the main component. The thickness of the metal film is in the range of 8% to 10% of the electrode pitch of the IDT of the parallel branch resonator.
摘要:
A three electrode type SAW longitudinal coupling filter includes a piezoelectric substrate having an electromechanical coupling factor (K.sup.2) higher than 10% and, three sets in total of input electrodes and output electrodes. Each of the electrodes includes a plurality of a electrode fingers of comb shape and are formed on the piezoelectric substrate. Reflectors are disposed at opposite sides of the input electrodes and output electrodes. The number of pairs of electrode fingers of the input electrodes is differentiated from the number of pairs of electrode fingers of the output electrodes. By the above arrangement, a large pass-band width can be obtained with small ripples and with an increase of the attenuation amount outside the band region.
摘要:
The present invention relates to an electronic part used for mobile communications apparatuses and the like, and more particularly to an electronic part, such as an acoustic surface-wave device, a piezoelectric ceramic device or the like, which requires an oscillation space near the surface of the functional device chip thereof, and a method of production thereof. With this method, a space retainer for forming a sealed space at the functional portion of the chip can be hermetically sealed and have high moisture resistance, and the process of forming the space retainer can be carried out easily.The electronic part of the present invention comprises a functional device chip, a space retainer for forming a sealed space at the functional portion of the chip, a circuit substrate to which the chip is secured, electrode interconnection portions for establishing electric connection between the chip and the circuit substrate, and a sealing resin for covering and sealing at least the space retainer, wherein the space retainer comprises a support layer made of a synthetic resin film, provided with an opening enclosing the functional portion and joined onto the main surface, and a cover formed and joined onto the support layer so as to cover the functional portion and form a sealed space between the cover and the functional portion.
摘要:
A high-frequency surface acoustic wave filter is such that a plurality of comb electrodes are formed on a piezoelectric substrate, and said high-frequency surface acoustic wave filter has:said piezoelectric substrate;an input terminal;an output terminal; andat least two ground terminals provided on said piezoelectric substrate,wherein said ground terminals are neither connected on said piezoelectric substrate nor connected in a package containing said piezoelectric substrate.