Alps Electric Co., Ltd.

Kazuhiko Ueda

Akiyuki Yoshisato

Akihiko Inoue

Hiroshi Sakuma

Yasuhiro Ikarashi

Hiroaki Kukita

Seiichi Yokoyama

Yasuhio Ikarashi

A conductive material such as silver is charged in a via hole of an insulative substrate made of low-temperature-sintered ceramic. A lower electrode, a dielectric layer, and an upper electrode are formed in a thin film on the insulative substrate. Thus a thin-film capacitor element is formed in which the capacitance value of the capacitor is specified by the overlapping part of the lower electrode and the upper electrode opposed through the dielectric layer. The dielectric layer is shaped like a ring with the via hole (conductive material) as the center and the part exposed inward from the inner periphery of the dielectric layer is served as a lead section of the lower electrode. The lead section is connected to a ground electrode on the back of the insulative substrate through the conductive material.

Thin-film capacitor element with reduced inductance component

The invention provides a surface mounting type electronic circuit unit that is suitable for miniaturization. Thin film circuit elements including capacitors, resistors, and inductance elements are formed on an alumina substrate, a semiconductor bare chip of a diode and a transistor is fixed by means of wire bonding, and part of the capacitors is formed non-rectangular having rectangles projected from one side of another rectangle.

Electronic circuit unit suitable for miniaturization

Thin film circuit elements including capacitors, resistors, and inductance elements are formed on a large substrate, and semiconductor chips are wire bonded to the substrate. The elements and chips are sealed by potting a sealing resin. The large substrate is divided into multiple stripe substrates by dicing and a thin-film conductive layer is sputtered on cut surfaces of the stripe substrates, thereby electrically connecting edges of lower conductive patterns to edges of upper conductive patterns exposed from side surfaces of the sealing resin through the thin-film conductive layer. A Ni foundation layer and Au layer are successively plated on a surface of the thin-film conductive layer to form edge electrodes on side surfaces of the stripe substrates and the stripe substrates are divided finely into individual alumina substrates.

Surface-mounting type of electronic circuit unit suitable for miniaturization and a method for fabricating the unit

The invention provides a surface mounting type electronic circuit unit that is suitable for miniaturization and is suitable for simple output adjustment. Circuit elements including capacitors, resistors, and inductance elements and a conducting pattern connected to the circuit elements are formed on an alumina substrate by means of thin film forming technique, and a diode D and a semiconductor chip of a transistor are fixed to a connection land of the conducting pattern by means of wire bonding, wherein only the emitter resistor out of the base bias voltage dividing resistors and the emitter resistor of the transistor is trimmed for output adjustment.

Electronic circuit unit that is suitable for miniaturization and suitable for simple output adjustment

In a surface-mounting-type electronic-circuit unit, circuit elements, including capacitors, resistors, and inductive devices, and electrically conductive patterns connected to the circuit elements are formed on an alumina board as thin films. Semiconductor bare chips for a diode and a transistor are wire-bonded to connection lands in electrically conductive patterns. And end-face electrodes connected to grounding electrodes, input electrodes, and output electrodes of electrically conductive patterns are formed at side faces of the alumina board.

Compact, surface-mounting-type, electronic-circuit unit

An oscillator includes an oscillation circuit unit and an amplification circuit unit of the common-base type. The oscillation circuit unit includes an oscillation transistor and a resonance circuit, the collector of the oscillation transistor being grounded via a first capacitor. The amplification circuit unit includes an amplification transistor, the emitter thereof being directly connected to the collector of the oscillation transistor and the base thereof being grounded via a second capacitor. The resonance circuit is connected between the base of the oscillation transistor and the ground. An oscillation signal output from the collector of the oscillation transistor is input to the emitter of the amplification transistor while partially being bypassed to the ground via the first capacitor. Negative feedback is provided to the amplification transistor in association with the second capacitor.

Oscillator with constant output level over oscillation frequency range

The invention provides an electronic circuit unit that is suitable for miniaturization and excellent in high frequency characteristic. Capacitors and a wiring pattern are formed on an alumina substrate by means of thin film forming technique, and a part of the wiring pattern is served as the connection land for mounting a bare chip of a transistor. Among the capacitors, the top electrode of the capacitor is served also as a part of the connection land, and the bottom side collector electrode of the bare chip is connected to the connection land by use of conductive adhesive. Top electrodes of the residual capacitors are served as the bonding pad, and the base electrode and the emitter electrode on the top side of the bare chip are connected to the top electrodes of the respective capacitors by a wire.

Electronic circuit unit that is suitable for miniaturization and excellent in high frequency characteristic

To provide a surface-mounting type electronic circuit unit suitable for miniaturization, circuit elements including capacitors, resistors and inductance elements and a conductive pattern connected to these circuit elements are thinly formed on an alumina substrate, semiconductor bare chips for a diode and a transistor are bonded on a connection land of the conductive pattern via wire, an inductance element composed of a pair of conductors opposite at a predetermined interval on the aluminum board is thinly formed and a unbalance/balance converter is formed by these conductors.

Growing community of inventors

Fukushima-ken, Japan

Kazuhiko Ueda