摘要:
An acoustic wave filter having excellent steepness is provided without adding any exterior components or any new manufacturing steps. A plurality of filters (10-1) each having a first resonator (2a-1) placed in a serial arm and having a resonance frequency frs and an anti-resonance frequency fas, and a second resonator (4a-1) placed in a parallel arm and having a resonance frequency frp and an anti-resonance frequency fap are provided on a same substrate, where the resonance frequency frs of the first resonator is higher than the resonance frequency frp of the second resonator; the anti-resonance frequency fas of the first resonator is higher than the anti-resonance frequency fap of the second resonator; and the filters (10-1) are connected in multiple stages. At least one of the filters (10-1) connected in multiple stages has a third resonator (6-1) having a resonance frequency frp and an anti-resonance frequency fap. The third resonator (6-1) is formed on the substrate and connected to the serial arm in parallel with respect to the first resonator (2a-1).
摘要:
A piezoelectric thin film resonator includes a substrate, a lower electrode formed on the substrate, a piezoelectric film formed on the lower electrode, and an upper electrode formed on the piezoelectric film, the lower electrode and the upper electrode opposing each other through the piezoelectric film to form an opposing region, the opposing region including a space at a boundary of the opposing region. The space extends from an innerside to an outer side of the opposing region and is formed in or on the piezoelectric film.
摘要:
A method of manufacturing an elastic wave device is provided with a lamination step of forming, on a substrate (1), a plurality of elastic wave devices, each of which includes a lower electrode (2), a piezoelectric film (3), and an upper electrode (4); a measuring step for measuring the operation frequency distribution of the elastic wave devices on the substrate (1); and an adjusting step for forming an adjusting region, in which the thickness of the elastic wave device is different from the thicknesses of other portions in a resonance portion of each elastic wave device, corresponding with the distribution of the operation frequencies. The adjusting region is formed so that the size of the area of the adjusting region of the resonator portion of each elastic wave device is different in accordance with the operation frequency distribution that is measured. Thus, the frequency characteristics of the elastic wave devices are easily adjusted by a small number of steps.
摘要:
A resonator includes a substrate, a lower electrode, a piezoelectric film provided on the lower electrode, and an upper electrode provided on the piezoelectric film. The lower electrode includes a first film provided on the substrate, and a second film that is provided on the first film and has a specific gravity greater than that of the first film. The piezoelectric film is provided on the second film. The upper electrode includes a third film provided on the piezoelectric film, and a fourth film provided on the third film, the third film having a specific gravity greater than that of the fourth film. The third film is thicker than the second film.
摘要:
A method for manufacturing a semiconductor device having a compound semiconductor layer that is provided on a substrate and includes a cladding layer of a first conductivity type, an activation layer, a cladding layer of a second conductivity type that is the opposite of the first conductivity type, includes the steps of: forming a diffusion source layer on the compound semiconductor layer; forming a first diffusion region in the compound semiconductor layer by carrying out a first heat treatment, so that the first diffusion region includes a light emitting facet for emitting light from the activation layer; removing the diffusion source layer; forming a first SiN film having a refractive index of 1.9 or higher on the compound semiconductor layer; and turning the first diffusion region into the second diffusion region by carrying out a second heat treatment.
摘要:
A piezoelectric thin film resonator includes a substrate, a lower electrode formed on the substrate, a piezoelectric film formed on the lower electrode, and an upper electrode formed on the piezoelectric film, the lower electrode and the upper electrode opposing each other through the piezoelectric film to form an opposing region, the opposing region including a space at a boundary of the opposing region. The space extends from an innerside to an outer side of the opposing region and is formed in or on the piezoelectric film.
摘要:
A powder conveying unit conveys powder input from a powder inlet of a powder containing chamber into the powder containing chamber. A powder detecting unit detects a full state of the powder conveyed by the powder conveying unit in the powder containing chamber. A sensor chamber is provided outside the powder containing chamber connected with each other. The powder detecting unit is provided in the sensor chamber, a bottom surface of the sensor chamber is at higher level than a bottom surface of the powder containing chamber, and the bottom surface of the sensor chamber is inclined downward toward the powder containing chamber.
摘要:
A filter includes multiple piezoelectric thin-film resonators each having a substrate, a lower electrode formed on the substrate, a piezoelectric film formed on the lower electrode, and an upper electrode provided on the piezoelectric film so that the upper electrode and the lower electrode face each other across the piezoelectric film. The multiple piezoelectric thin-film resonators include a first resonator in which at least a part of an outer curved portion of the piezoelectric film of the first resonator is located further out than an outer curved portion of a region in which the upper electrode and the lower electrode face each other across the piezoelectric film. The multiple piezoelectric thin-film resonators includes a second resonator in which at least a part of an outer curved portion of the piezoelectric film of the second resonator substantially coincides with an outer curved portion of a region in which the upper electrode and the lower electrode face each other across the piezoelectric film or is further in than the outer curved portion of the region.
摘要:
A filter element includes resonators that are arranged in series arms and parallel arms in a circuit. In this filter element, at least one of the series-arm resonators includes a plurality of single-terminal pair piezoelectric thin-film resonators connected in parallel.
摘要:
A polyamide composition comprising a polycondensate of 60 to 100 mole % of terephthalic acid component units and 40 to 0 mole % of units of an aromatic carboxylic acid other than terephthalic acid with an aliphatic alkylene-diamine having 6 to 18 carbon atoms and having a gel proportion of 6 to 90% as measured at 50.degree. C. in concentrated sulfuric acid.