摘要:
An energy storage circuit includes a first capacitor connected with a power generating element via a first diode and a second capacitor connected with the power generating element via a second diode and a switch. The conduction state of the switch is controlled using the potential difference between its second and third electrodes (driving voltage V). The driving voltage when the switch enters its conductive state is higher than the driving voltage when the switch enters its non-conductive state.
摘要:
A thin film piezoelectric bulk acoustic wave resonator has a multilayer structure including a piezoelectric thin film, a first metal electrode film, and a second metal electrode film. At least a part of the piezoelectric thin film is interposed between the first and second metal electrodes. A resonance part and a connection part are formed on an insulating substrate as films by a thin film forming apparatus. The resonance part vibrates in radial extension mode with a center of the piezoelectric thin film used as a node, the piezoelectric thin film of two resonance parts is polarized in a direction perpendicular to a film surface, and a width of the connection part is one-fourth or less of a width of two resonance parts.
摘要:
The film bulk acoustic wave resonator includes a laminate structure composed of a piezoelectric layer, and first and second electrode layers interposing at least part of the piezoelectric layer, in which the first metal electrode is dispersively formed on an electrode plane facing the second metal electrode, and a gap is formed in a substrate correspondingly to the laminate-structured resonance part. Except for an area of a wire electrode electrically connected to the first electrode layer and an area of a wire electrode electrically connected to the second electrode layer, the piezoelectric layer, first electrode layer and second electrode layer do not come in contact with the insulating substrate but are supported on a hollow. Also, a prop is formed in the gap to support the laminate structure.
摘要:
An object of the present invention is to provide an inexpensive thin film piezoelectric bulk acoustic wave resonator that allows fine-tuning of a resonant frequency. Another object is to provide an inexpensive filter with dramatically improved frequency characteristics, using thin film piezoelectric bulk acoustic wave resonators that can be formed on one substrate. A thin film piezoelectric bulk acoustic wave resonator of the present invention has a laminated structure including a piezoelectric thin film, and a first metal electrode film and a second metal electrode film between which part of the piezoelectric thin film is sandwiched; the first metal electrode film has a plurality of holes formed on an electrode plane opposite to the second metal electrode film and having a depth equivalent to at least the thickness of the first metal electrode film; and if a combined thickness of top and bottom electrode layers and the piezoelectric thin film is ht, the covering ratio σ of the electrode plane of the first metal electrode film satisfies a condition 0
摘要:
A mask structure has two (or more) groups of device patterns formed on one transparent support plate. Each of the device patterns has a transparent partial pattern. One or both of the groups of device patterns are provided with phase shifting patterns for improvement of the resolution in the lithography. The transparent partial pattern in each of the device patterns in each of the device pattern groups is determined such that each of the transparent partial patterns held by one of the device pattern groups is adapted for combination with one transparent partial pattern held by the other device pattern group by two or more times of transmission of an exposure beam through the mask structure. Manufacturing of solid-state devices is possible by use of the mask structure, in which exposure of a photo-sensitive film on a substrate to an exposure beam through the mask structure is repeated two or more times with a relative position between the mask structure and the substrate being changed.
摘要:
A thin-film piezoelectric acoustic wave resonator that has a large k2, can trap acoustic energy in a resonating part, does not excite spurious resonance, or can finely adjust resonance frequency and a high-frequency filter using the thin-film piezoelectric acoustic wave resonator are provided without increasing the number of processes. At both ends of a vibrating part (1), fixing parts (8) are physically connected, and between the vibrating part (1) and each of the fixing parts (8), an acoustic insulating part (10) and a phase rotating part (11) are physically connected. As with the vibrating part (1), the acoustic insulating part (10) and the phase rotating part (11) are made up of an upper metal film (3), a piezoelectric thin film, and a lower metal film, and an acoustic wave reflector (6) is provided on each of an upper surface, a lower surface, and side surfaces of the vibrating part (1), the acoustic insulating part (10), and the phase rotating part (11). The vibrating part (1) has a width smaller than its length (La) and also smaller than its thickness, and width/thickness is smaller than 1.
摘要:
A compact resonator has a wide bandwidth and a small variation of the specific vibration frequency. The resonator is a thin film tuning-fork type inflection resonator in which a thin film made of a piezoelectric material is formed on a substrate on which a lower electrode is formed, and an upper electrode is formed on the piezoelectric thin film.
摘要:
A surface acoustic wave device in the present invention is provided with a piezoelectric substrate, a supporting substrate being jointed to the piezoelectric substrate and including a material different in expansion coefficient from the piezoelectric substrate and an interdigital electrode for exciting a surface acoustic wave, the electrode being arranged on the surface of the piezoelectric substrate. Either the interdigital electrode or the piezoelectric substrate is configured so that the interdigital electrode is 40% or more to 70% or less as long as the piezoelectric substrate in the direction to which a surface acoustic wave propagates.
摘要:
A thin film piezoelectric bulk acoustic wave resonator has a multilayer structure including a piezoelectric thin film, a first metal electrode film, and a second metal electrode film. At least a part of the piezoelectric thin film is interposed between the first and second metal electrodes. A resonance part and a connection part are formed on an insulating substrate as films by a thin film forming apparatus. The resonance part vibrates in radial extension mode with a center of the piezoelectric thin film used as a node, the piezoelectric thin film of two resonance parts is polarized in a direction perpendicular to a film surface, and a width of the connection part is one-fourth or less of a width of two resonance parts.
摘要:
The present invention provides a film bulk acoustic wave resonator (FBAR) filter that can keep the Q factor high. The FBAR filter comprises a first FBAR with a first resonant frequency and a second FBAR with a second resonant frequency, formed on a same substrate. The FBAR filter has such a structure that a first underlayer is formed between the substrate and a first bottom electrode layer and a second underlayer is formed between the substrate and a second bottom electrode layer, the first underlayer thickness being different from the second underlayer thickness.