Nihon Dempa Kogyo Co., Ltd.

Toshimasa Tsuda

Tatsunori Onzuka

Kenji Kawahata

Junichiro Yamakawa

Hiroshi Hoshigami

Yasushi Yamamoto

Kazuo Akaike

Susumu Yoshimoto

Mikio Takano

Minoru Sakai

Hiroyuki Sasaki

Tomotaka Kuroda

Makoto Hatano

Daisuke Nishiyama

Kenichi Kikuchi

Kietsu Saito

Hiroya Ishikawa

Ryouichi Fujiyama

Seiji Abe

Natsuhiko Sakairi

A solder material includes an alloy of at least five elements including Sn, Cu, Sb, and In, and 20 mass % or less of Ag. The solidus temperature of the solder material is higher than 290&#xb0; C., the liquidus temperature of the solder material is 379&#xb0; C. or less and is higher than the solidus temperature, and the temperature difference between the liquidus temperature and the solidus temperature is 70&#xb0; C. or less.

Solder material and electronic component

A piezoelectric component includes a piezoelectric element that includes: a piezoelectric plate; a comb-shaped electrode and an input/output electrode on a principal surface of the piezoelectric plate; a cover layer disposed above the comb-shaped electrode; and a rib to form a void between the comb-shaped electrode and the cover layer. The cover layer includes a photosensitive thermosetting resin in which translucent filler is contained.

Piezoelectric component having a cover layer including resin that contains translucent filler

A manufacturing method, which realizes general versatility of an external connection terminal by reducing deterioration of characteristics and a decrease in yield rate of a piezoelectric device in an external connection terminal forming process, and a piezoelectric device manufactured by this method are provided. Before a piezoelectric device is sealed together with a ceiling layer to form a package, an electrode structure serving as an external connection terminal is provided beforehand on a substrate mounted with a key area of the device, and after formation of the key area of the device, the piezoelectric device is sealed and packaged together with the ceiling layer. The piezoelectric device of the present invention can accommodate a three-dimensional structure by providing a rewiring layer on a principal surface of the substrate.

Piezoelectric device and manufacturing method therefor

There is provided a voltage controlled oscillator that is compact and can be manufactured at low cost. The voltage controlled oscillator is structured to include: a resonance part including a variable capacitance element and an inductance element, the variable capacitance element having a capacitance that varies according to a control voltage for frequency control input from an external part, and a series resonant frequency of the resonance part being adjusted according to the capacitance; an amplifying part amplifying a frequency signal from the resonance part; and a feedback part including a capacitance element for feedback and feeding the frequency signal amplified by the amplifying part back to the resonance part to form an oscillation loop together with the amplifying part and the resonance part, wherein the amplifying part is provided in an integrated circuit chip, and the resonance part and the capacitance element for feedback are formed as circuit components separate from the integrated circuit chip. The circuit components are selected according to an oscillation frequency.

Voltage controlled oscillator

A piezoelectric component including a piezoelectric device having wiring electrodes disposed adjacent to a comb electrode and an insulation layer formed on an upper surface of a piezoelectric section. A rewiring layer is formed on an upper surface of the insulation layer and a protective film layer covers the entire upper surface of the rewiring layer excluding the comb electrode. An outer periphery wall section is formed by laminating a photosensitive resin film onto the protective film layer and a ceiling section is formed by laminating the photosensitive resin film onto top openings of the outer periphery wall section. Electrode posts are formed so as to pass through the outer periphery wall section and the ceiling section.

Piezoelectric component and manufacturing method thereof

To provide a voltage controlled oscillator having small size and capable of obtaining a low phase noise characteristic over a large span of adjustable range of frequency. A quartz crystal having a characteristic (dielectric loss tangent: tan &#x3b4;) better than that of fluorocarbon resin, LTCC or the like conventionally used as a substrate of a resonance part, and on which a fine pattern of metal film can be formed through a photolithography method, is used as a quartz-crystal substrate, and a conductive line is formed on the quartz-crystal substrate to form an inductance element in the resonance part. Accordingly, since the resonance part having a high Q value can be formed, it is possible to obtain a voltage controlled oscillator having small size and low loss over a wide frequency range.

Voltage controlled oscillator and electronic component

A piezoelectric component manufacturing method is provided. The method includes preparing an integrated piezoelectric substrate, and forming comb-shaped electrodes and wiring electrodes having element wiring connecting to the comb-shape electrodes on a primary surface of the piezoelectric substrate, forming an SiOlayer, performing a characteristics inspection on the piezoelectric substrate and marking defective piezoelectric elements, coating said SiOlayer surface with photosensitive resin, and then exposing and developing to form an insulating layer. The method includes vapor-depositing a metal layer, and removing said metal layer adhered to resist by an organic solvent when removing the resist, to form a rewiring layer, coating said rewiring layer with photosensitive resin, affixing a photosensitive resin film to a top end surface of said photosensitive resin layer, forming electrode posts in the holes by electroplating, and dicing said piezoelectric substrate along scribe lines to obtain individual piezoelectric components.

Method of manufacturing a piezoelectric component

To provide a voltage controlled oscillator capable of being treated as a lumped constant circuit, having small size and capable of obtaining an oscillation frequency in a high frequency band. A resonance part in a voltage controlled oscillator has variable capacitance elements whose electrostatic capacitance varies in accordance with a control voltage for frequency control input from the outside and an inductance element, an amplifying part amplifies a frequency signal from the resonance part, and a feedback part, having feedback capacitance elements, forms an oscillation loop together with the amplifying part and the resonance part by making the frequency signal amplified in the amplifying part to be fed back to the resonance part. Further, the resonance part and the feedback part are provided on a quartz-crystal substrate.

There is provided a voltage controlled oscillator using a Colpitts circuit capable of suppressing deterioration (decrease) in variable range (adjustable range) of an output frequency due to the influence of an inductance component on a conductive line, which connects a connection point between two capacitors of a feedback part and an emitter of a transistor. In a VCO using a Colpitts circuit, with respect to capacitorsof a feedback part, a first feedback capacitance element (capacitor)is disposed so as to directly couple a terminal for base (connection part) and a terminal for emitter on a base substrate, to which a terminal part(T) extending from a base of a transistorand a terminal part(T) extending from an emitter of the transistorare fitted, respectively, and a second feedback capacitance element (capacitor)is disposed so as to directly couple the terminal for emitter and the terminal for grounding (ground electrode).

An object of the present invention is to economically manufacture a piezoelectric component having superior molding pressure resistance and reduced height. The present invention comprising: a piezoelectric substrate with piezoelectric devices formed on a principle surface; a device wiring section formed on the principle surface; protective film having a terminal electrode connected to the wiring section formed on its upper surface; a rewiring layer on an upper surface of the protective film and connected to a wiring section of another electrode; an inorganic material-buffer layer covers an entire upper surface of the rewiring layer excluding the piezoelectric devices; a photosensitive film-outer periphery wall, formed on an upper surface of the buffer layer; a photosensitive film-first ceiling layer, having mica filler added thereto is formed on an upper surface of the outer periphery wall; an insulating material mesh-shaped member, installed on an upper surface of the first ceiling layer; a photosensitive resin film-second ceiling layer with mica filler added thereto covers an upper surface of the mesh-shaped member; and through electrodes that pass through the first and second ceiling layers, the outer periphery wall, and the mesh-shaped member, thus between the outer periphery wall, the first ceiling layer, and the principle surface of the piezoelectric substrate, there is a hollow that accommodates the piezoelectric devices.

A method for forming a piezoelectric component includes forming a plurality of sets of first piezoelectric elements having comb-shaped electrodes and wiring electrodes on a principal surface of a piezoelectric substrate base material, forming a protective film, a seed layer, and terminal electrodes, and removing the seed layer by etching. The method further includes preparing another piezoelectric substrate and performing resin-sealing by laminating a photosensitive resin film onto a principal surface side of the piezoelectric substrate base material. Cu electroplating is performed upon the terminal electrodes, and the piezoelectric substrate base material is cut along dicing lines to obtain individual piezoelectric components. The piezoelectric component includes a first piezoelectric element and a plurality of second piezoelectric elements with the second piezoelectric elements sealed by a resin seal layer such that a hollow section is formed between opposing principal surfaces thereof.

A piezoelectric component with a piezoelectric element includes a piezoelectric substrate, at least one oscillating section formed on the piezoelectric substrate, and an element wiring section connected to the oscillating section. A side face side hollow section forming layer and a lid face side hollow section forming layer made of photosensitive resin surround the top face and side face of the oscillating section while forming a gap so as to provide a hollow section.

There is provided an electronic component excellent in moisture resistance capable of ensuring electrical connection between electrodes and hermeticity of a sealed region including a vibrating part and suppressing an increase in size. An electronic component including a piezoelectric element provided with a vibrating part and a first electrode on one face of a piezoelectric substrate and a printed circuit substrate having a second electrode is constituted by including: a bump provided in advance on one of the first electrode and the second electrode and connected to the other of the first electrode and the second electrode; an annular first metal layer surrounding the vibrating part; and a solder material with a solidus temperature lower than the bump, sealing a space between the first metal layer and the printed circuit substrate to make a placement region of the vibrating part a hermetic space, whereby moisture permeation into the hermetic space and the outward spread of the solder material can be suppressed, and a space for the bump to spread by being melted can be omitted. Moreover, the electrical connection between the electrodes and the sealing of the placement region can be performed in separate processes, so that high hermeticity can be obtained.

Growing community of inventors

Saitama, Japan

Toshimasa Tsuda