摘要:
A surface acoustic wave device includes a piezoelectric substrate, an interdigital transducer (IDT) electrode, and a connecting portion that is electrically connected with the IDT electrode. The surface acoustic wave device further includes a wiring portion, a portion of which is disposed on the connecting portion, and a bump disposed on the wiring portion. The connecting portion includes a comb-shaped portion at an end of the connecting portion on which the wiring portion is disposed.
摘要:
A method for efficiently and inexpensively manufacturing a piezoelectric element that contains highly corrosion resistant electrodes and has excellent and stable electric characteristics is performing such that dicing occurs without forming any protective film beforehand. According to the method, a wafer is formed to have an electrode including an Al alloy disposed on a piezoelectric substrate made of a piezoelectric material. The wafer is cut while being exposed to plasma using a halogen-containing gas while cooling the wafer with cutting water. The cutting water preferably includes a compound that reacts with Al to form a protective film on a surface of an electrode including an Al alloy.
摘要:
A surface acoustic wave device includes a piezoelectric substrate, and comb-shaped electrodes each having a bus bar and a plurality of electrode fingers disposed on the piezoelectric substrate. At least one of the fingers and the bus bar are connected to each other via at least two different connecting portions at two different locations.
摘要:
A host vector system comprising Rhizopus species such as Rhizopus niveus (IFO4810) and a plasmid derived from Phycomycetes such as Mucor, Phycomyces and Absidia wherein the plasmid is contained in a chromosome and/or cytoplasm of the Rhizopus species. The host vector system is suitable for the extracellular production of proteins and enzymes. A process for preparing the host vector system is also provided.
摘要:
A surface acoustic wave device includes a piezoelectric substrate, an interdigital transducer (IDT) electrode, and a connecting portion that is electrically connected with the IDT electrode. The surface acoustic wave device further includes a wiring portion, a portion of which is disposed on the connecting portion, and a bump disposed on the wiring portion. The connecting portion includes a comb-shaped portion at an end of the connecting portion on which the wiring portion is disposed.
摘要:
A surface acoustic wave device includes a surface acoustic wave element, a packaging case, and a packaging electrode. The surface acoustic wave element has a piezoelectric substrate, an interdigital transducer, an electrode pad, an intermediate electrode, an upper electrode, and a bump electrode. The intermediate electrode is preferably made of NiCr including about 15 to about 30 weight percent of Cr. The electrode pad and upper electrode are made of Al. The bump electrode is press-bonded to the packaging electrode with an ultrasonic wave or heat applied to the bump electrode. The resulting surface acoustic wave device has excellent characteristics and the surface acoustic wave element is not removed or peeled from the packaging case during a drop test.
摘要:
A surface acoustic wave device includes a piezoelectric substrate, a first surface acoustic wave element having at least one interdigital transducer on the piezoelectric substrate, a second surface acoustic wave element having at least one interdigital transducer which is provided on the piezoelectric substrate. The at least one interdigital transducer of the second surface acoustic wave element has a thickness that is different from the interdigital transducer of the first surface acoustic wave element, and the second surface acoustic wave element has a frequency characteristic that is different from that of the first surface acoustic wave element. An insulating film is applied to the first and second surface acoustic wave elements. A thickness of the insulating film at a region on the first surface acoustic wave element is different from the thickness of a region on the second surface acoustic wave.
摘要:
A method of making surface acoustic wave device includes a piezoelectric substrate, a first surface acoustic wave element having at least one interdigital transducer on the piezoelectric substrate, a second surface acoustic wave element having at least one interdigital transducer which is provided on the piezoelectric substrate. The at least one interdigital transducer of the second surface acoustic wave element has a thickness that is different from the interdigital transducer of the first surface acoustic wave element, and the second surface acoustic wave element has a frequency characteristic that is different from that of the first surface acoustic wave element. An insulating film is applied to the first and second surface acoustic wave elements. A thickness of the insulating film at a region on the first surface acoustic wave element is different from the thickness of a region on the second surface acoustic wave.
摘要:
The method for preparation of sintered permanent magnets according to the present invention comprises the steps of: mixing fully fine powder of a crystalline mother alloy for permanent magnet containing a rare-earth element, Fe and B as the essential components with fine powder of zinc oxide, compaction molding the resulted mixture in the presence of a magnetic field, sintering the compacted mixture in vacuum to cause generation of oxygen and metallic zinc by thermal decomposition of the zinc oxide; segregation of a part of metallic component in the mother alloy at the boundary and inside of the mother alloy crystal; formation of amorphous metallic oxide by forced oxidation of the segregated metal with the generated oxygen; crystallization of the amorphous metallic oxide; formation of an epitaxial junction between the crystallized metallic oxide and the mother alloy crystal; and evaporation of the metallic zinc into the vacuum, and quenching the sintered compact.
摘要:
A method of forming an electrode pattern of a surface acoustic wave device easily and reliably prevents the occurrence of an abnormality in the shape of a resist pattern. In the electrode pattern forming method, a resist layer is formed on a top surface of a piezoelectric substrate, and then exposed to ultraviolet rays through a photomask provided above the top surface of the piezoelectric substrate to form a resist pattern on the surface of the piezoelectric substrate. Furthermore, a conductor film is formed on the top surface of the piezoelectric substrate, and the resist pattern is removed by a liftoff method to form an electrode pattern of the surface acoustic wave device. Exposure is performed using ultraviolet rays having a wavelength which is completely absorbed into the piezoelectric substrate without reaching the bottom surface of the piezoelectric substrate.