High-permittivity ceramics make it possible to noticeably miniaturize passive microwave devices. These ceramics must fulfil the requirements of high permittivity, very low dielectric losses and an extremely low temperature dependence of permittivity to yield temperature-stable resonators. Recent progress has been made in understanding the physics of microwave ceramics, particularly the property-structure relationship, in developing new materials with higher permittivity, better temperature stability and considerably lower sintering temperature, and in making co-fired multilayer devices possible, as well as in developing new microwave devices such as oscillators, antennas and band-pass filters.

Microwave ceramics for resonators and filters

An electronic device and a fabricating method for fabricating the electronic device, the electronic device comprising; a surface acoustic wave device 3 having a main surface thereon having a transducer portion 4 and wiring patterns 5 connected electrically to the transducer portion; a printed circuit board 1 having wiring patterns 2 formed at least on one main surface thereof; a plurality of conductive bumps 6 which connect electrically both of the mutually opposed wiring patterns and form a space portion 10 between the surface acoustic wave device 3 and a printed circuit board 1; and resin portion 11 which, by heating/melting and hardening, makes an intimate contact with other main surface of the device and coats the device 3 and seals the device 3 together with the printed circuit board 1, wherein, by employing a highly thixotropic and viscous thermo-setting resin compared with a conventional one, an electronic device having a simple structure can be provided and fabricating process for fabricating the electronic device can be simplified.

Electronic component and method of production thereof

A high-frequency switch module which comprises a high-frequency switch circuit connected among an antenna, a transmission circuit, and a reception circuit and comprising switching elements and a surface acoustic wave filter connected between the high-frequency switch circuit and the reception circuit, uses a laminate constituted of dielectric layers having electrode patterns as the multilayered board, and has a phase correction circuit disposed between the switch circuit and the surface acoustic wave filter, wherein the high-frequency switch circuit comprises a switching element, a transmission line, and a capacitor as main elements, with at least a part of the transmission line and the capacitor constituted of an electrode pattern in the laminate, and with the surface acoustic wave filter mounted on the laminate.

High-frequency switch module

An electromagnetic bandgap structure and a printed circuit board that solve a mixed signal problem are disclosed. In accordance with embodiments of the present invention, the electromagnetic bandgap structure includes a first metal layer; a first dielectric layer, stacked in the first metal layer; a second metal layer, stacked in the first dielectric layer, and having a holed formed at a position of the second dielectric layer; a second dielectric layer, stacked in the second metal layer; a metal plate, stacked in the second dielectric layer; a first via, penetrating the hole formed in the second metal layer and connecting the first metal layer and the metal plate; a third dielectric layer, stacked in the metal plate and the second dielectric layer; a third metal layer, stacked in the third dielectric layer; and a second via, connecting the second metal layer to the third metal layer.

Electromagnetic bandgap structure and printed circuit board

An electronic component having a multi-layered printed circuit board made of an organic material, a plurality of electronic components mounted in a face-down position on the multi-layered printed circuit board, a metal cover for covering the plurality of electronic components remaining a space or a cavity between the top surface of the printed circuit board and the inner surface of the metal cover having a flange surrounding the outskirts of the metal cover to be adhered to the top surface of the multi-layered printed circuit board, and a heat conductive member packed between the bottom surface of the electronic components, wherein the multi-layered printed circuit board has at least one through-hole vertically penetrating the multi-layered printed circuit board at a location corresponding to the flange and is lined by a metal film, and the multi-layered printed circuit board has a heat conductive layer arranged along the rear surface of the multi-layered printed circuit board, the heat conductive layer being connected to a metal lining of the through-hole.

Electronic component utilizing face-down mounting

A surface acoustic wave device including a dielectric substrate having an input electrode and an output electrode and a grounding electrode on a first surface of the dielectric substrate, and an outer electrode on a second surface of the dielectric substrate; and a surface acoustic wave element having an electrode pad and a comb-shaped electrode disposed on a first surface of the surface acoustic wave element. The surface acoustic wave element is bonded to the dielectric substrate via a metal bump and a conductive resin formed on the electrode pad. The surface acoustic wave device further includes an insulating resin deposited on the periphery of the metal bump, and a guard layer shorter in height than the surface acoustic wave element formed adjacent the surface acoustic wave element on the first surface of the dielectric substrate.

Surface acoustic wave devices having a guard layer

A high frequency ceramic multi-layer substrate includes a stripline (1) embedded between two dielectric layers (2,2') having ground electrodes (3,4) at the top surface and at the bottom surface thereof and an electric circuit formed on another dielectric layer (5) applied to one of the ground electrodes. The stripline is connected to the electric circuit through via holes (6,6') provided through the dielectric layers. The equivalent length from the stripline to the electric circuit is a fourth of the wavelength of an input high frequency signal, to result in high frequency attenuation circuit. Another high frequency ceramic multi-layer substrate includes further another electrode provided via another dielectric layer of larger dielectric constant to form a capacitor with one of the ground electrodes, and a further dielectric layer for forming an electric circuit thereon is applied to the electrode. The stripline is connected to the electric circuit through via holes provided through dielectric layers. The electric circuit may be an impedance matching circuit of the stripline or a direct current bias circuit (8). This multi-layer structure makes the high frequency substrate compact and improves high frequency characteristics.

High frequency ceramic multi-layer substrate

PURPOSE:To obtain a satisfactory spurious characteristic in a high frequency band by laminating a layer where an electrode pattern is formed and preventing the occurrence of floating electrode between capacitor electrodes and between a strip line electrode and capacitor electrodes. CONSTITUTION:Capacitor electrodes 2, 3, and 4 form electrostatic capacities between earth electrodes 5 and 6, between earth electrodes 8 and 9, and between earth electrodes 6 and 7 respectively. The electrode 2 is connected to one connection terminal of a strip line electrode 1 by an external electrode, and the electrode 3 is connected to the other connection terminal of the electrode 1 by the external electrode. The electrode 4 is connected to the center part of the electrode 1 through a via hole 10. In an LPF having this constitution, capacitor electrodes 2 to 4 are made independent of one another through ground electrodes 5 to 9, and the elect trode 1 interposed between ground electrodes 5 to 9 is used as a coil electrode. Consequently, floating electrodes don't occur between capacitor electrodes neither between the strip line electrode and capacitor electrodes, and as the result, a satisfactory spurious characteristic is obtained in a high frequency band.

Chip type high frequency low pass filter

Microwave characteristics of alumina-glass composite multi-layer substrates with co-fired copper conductors

The invention is intended to present a surface acoustic wave device capable of preventing spreading of insulating resin and reducing in size. The constitution comprises a multi-layer substrate possessing input and output electrodes and grounding electrode on the mounting surface side of a dielectric layer, and possessing an outer electrode on the other surface of said electric layer, with said input and output electrodes and grounding electrode connected electrically with the outer electrode respectively, a surface acoustic wave element mounting a principal surface forming an electrode pad and comb-shaped electrode by face-down method, a metal bump applying a conductive resin on said electrode pad, and an insulating resin formed on the periphery of the metal bump, wherein said input and output electrodes, grounding electrode and surface acoustic wave element are electrically connected through the metal bump respectively, and a guard layer shorter in height than the surface acoustic wave element is formed outside of the surface acoustic wave element, on the mounting surface side of said multi-layer substrate.

Katsuyuki Miyauchi

Papers

Surface acoustic wave devices having a guard layer

High frequency ceramic multi-layer substrate

Chip type high frequency low pass filter

Microwave characteristics of alumina-glass composite multi-layer substrates with co-fired copper conductors

Surface acoustic wave devices