Kabushiki Kaisha Toshiba

Eiji Takagi

Yuji Iseki

Takeshi Miyagi

Naoko Ono

Kunio Yoshihara

Yasushi Shizuki

Takeshi Hanawa

Kazuhito Higuchi

Keiichi Yamaguchi

Kouhei Morizuka

Motoyasu Morinaga

Mitsuo Konno

Yasuo Ashizawa

Junko Akagi

Junko Onomura

Yasuhiro Kuriyama

A high frequency semiconductor device has a semiconductor substrate such as the semi-insulating GaAs; a first metal layer disposed above the semiconductor substrate; a first dielectric thin film disposed on the first metal layer; and a second metal layer having a second metal strip disposed on the first dielectric thin film. Here, the first metal layer has a first metal strip, first and second ground metal plates sandwiching the first metal strip. And the first dielectric thin film is not disposed uniformly on the surface of the first ground metal plate so that the dielectric structure on the first metal strip differs from the dielectric structure under the second metal strip. The CPW is constituted by the first metal strip, the first and second ground metal plates, and the TFMSL is constituted by the second metal strip and the first ground metal plate. By employing the structure such that there is no dielectric thin film on the CPW portion, or that the thickness of the dielectric thin film on the CPW portion is configured to be less than the thickness of the dielectric thin film associated with the TFMSL portion, the effective dielectric constant &isin; of the CPW portion is made lower than that of the conventional CPW, which employs a uniform and homogenous dielectric structure so that the CPW portion has the same thickness of the TFMSL portion. As the result, the adjustable range of the characteristic impedance Z of the high frequency transmission line, merged in the high frequency semiconductor integrated circuit, increases. Then the high-performance integrated circuits such as MMICs having the low transmission loss, the low crosstalk can be achieved.

Microwave semiconductor device having coplanar waveguide and micro-strip line

Disclosed is an ultra high frequency radio communication apparatus having: a receiver antenna; a transmitter antenna; an IC chip being electrically connected to the receiver antenna and the transmitter antenna; a substrate on which the receiver antenna, the transmitter antenna and the IC chip are mounted; an input terminal for inputting to the IC chip a base band input signal; an output terminal for outputting a base band output signal from the IC chip; and a control signal terminal for inputting a control signal for controlling the IC chip to the IC chip. The IC chip is placed in a shielding space such that the cut-off frequency of the shielding space is higher than the frequency of a carrier signal for radio communication.

Ultra high frequency radio communication apparatus

A wiring board for high-frequency signals, which comprises, a substrate, a dielectric layer formed on the substrate and provided on its surface with a U-shaped groove having an arcuate bottom for forming a wiring therein, and a signal wiring formed in the U-shaped groove, which is featured in that an upper end portion of the signal wiring is protruded out of the surface of the dielectric layer. A distance (H) from a protruded top surface of the signal wiring to a bottom of the U-shaped groove and a width (W) of the U-shaped groove preferably meet a relationship of 2&lt;(W/H)&lt;50, and the height of the portion of signal wiring which is protruded out of the surface of the dielectric layer is preferably in the range of 10 nm to 10 .mu.m.

Wiring board for high-frequency signals and semiconductor module for

A semiconductor device comprising a semiconductor chip, a sheet-like metal member electrically connected to a major surface of the semiconductor chip and serving as a ground electrode for the chip, and input/output electrodes electrically connected to the semiconductor chip and situated in the same plane as that of the sheet-like metal member, the chip, the metal member, and the input/output electrodes being encapsulated in an electrically insulating member having a bottom surface and adapted to be mounted on a surface of a circuit board. The sheet-like metal member is brought out from inside the electrically insulating member without being bent and has its one end face situated in substantially the same plane as the bottom surface of the electrically insulating member which faces to the surface of the circuit board when the metal member is mounted on the circuit board and the major surface of the chip is approximately prependicular to the end face of the sheet-like metal member.

Semiconductor device for ultrahigh frequency band and semiconductor

Growing community of inventors

Yokosuka, Japan

Eiji Takagi