Kabushiki Kaisha Toshiba

Toshiba Electronic Devices & Storage Corporation

Masami Nagaoka

Atsushi Kameyama

Kazuya Nishihori

Toshiki Seshita

Ikuo Fujiwara

Tadahiro Sasaki

Kenichi Tomita

Mayumi Morizuka

Yoshiko Ikeda

Katsue Kawakyu

Hirotsugu Wakimoto

Yoshiaki Kitaura

Keita Masuda

Tomotoshi Inoue

Atsushi Ishimaru

Naotaka Uchitomi

Hitoshi Mikami

Kenji Ishida

A semiconductor device includes an insulating layer, a semiconductor layer on the insulating layer, and a control electrode on the semiconductor layer. The semiconductor layer includes first and second semiconductor parts and a separation trench between the first and second semiconductor parts. The first and second semiconductor parts extending along the insulating film. The first semiconductor part includes first and second regions of a first conductivity type, and a fifth region of a second conductivity type between the first and second regions. The second semiconductor part includes third and fourth regions of the second conductivity type, and a sixth region of the second conductivity type between the third and fourth regions. The control electrode extends over the fifth and sixth regions. The semiconductor layer further including a seventh region of the second conductivity type at a bottom of the separation trench and electrically connecting the fifth and sixth regions.

Semiconductor device having semiconductor region at bottom of separation trench and connecting two semiconductor regions over which control electrode extends

According to an embodiment, a semiconductor switch includes a first insulating film on a semiconductor substrate, a first semiconductor layer on the first insulating film, a semiconductor switch circuit on the first semiconductor layer, and a wiring on the first insulating film. The first insulating film being between the wiring and the substrate. The wiring connects the semiconductor switch circuit and a terminal. A polycrystalline semiconductor layer is between the wiring and the first insulating film.

Semiconductor switch

A MESFET of a GaAs semiconductor device having a p-pocket LDD structure is used for a high-frequency power amplifier of a mobile communication device, in order to decrease current consumption and to increase the continuous operating time of a battery. The high-frequency power amplifier is provided with a gate-bias adjusting feedback element between the drain and gate of the MESFET. Thus, even if there is a great difference between the filled and terminated potentials of the discharge voltage of the battery for supplying electric power to the amplifier, electric power can be supplied near the terminated potential for a long time, so that the mobile communication device can be continuously used for a long time.

High-frequency power amplifier and mobile communication device using same

In order to minimize the chip area and improve the linear characteristics obtained when large signals are inputted, a high frequency switch device comprises first, second and third terminals (3, 4, 6); a first circuit composed of a first FET (11), and a first inductor (21) and a first capacitor (25) both connected with the first FET (11) in parallel to each other, one end of the first circuit being connected to the first terminal (3); and a second circuit composed of a second FET (12), and a second inductor (22) and a second capacitor (26) both connected with the second FET (12) in parallel to each other, one end of the second circuit being connected to the first circuit and the other end of the second circuit being connected to the second terminal (4). Further, the high frequency switch device is characterized in that a first control signal is applied to a gate of the first FET (11) via a resistance (31); a second control signal is applied to a gate of the second FET (12) via a resistance (33); the third terminal (6) is connected to a common junction point of the first and second circuits; and a predetermined potential is applied to the common junction point.

High frequency switch device, front end unit and transceiver

The invention provides a high frequency amplifier in which a variable attenuator consisting of a bypass FET, which has a drain connected to a first-stage amplifying FET via a resistor, and a source grounded via a capacitor, is located on a main signal line leading to the gate of the amplifying FET, in order to control the gate potential of a bypass FET using a gain control voltage source, thereby varying the gain of the amplifier.

High frequency amplifier having a variable attenuator connected to the

There is provided a semiconductor amplifier including a metal-semiconductor field-effect transistor (MESFET) of a source-ground type, having a threshold voltage of a predetermined value within a range of -0.5V to 0V (more preferably, -0.4V to -0.04V), and driving by a single power supply without applying a bias on a gate of the MESFET. According to the above semiconductor amplifier, very high efficiency can be realized while maintaining a sufficiently high output power.

Metal semiconductor field effect transistor of source-ground type

An integrated circuit includes an amplifier for amplifying input electric power having a predetermined frequency determined depending on an application and a series capacitor connected to an output side of the amplifier and becoming a conductive state with respect to the electric current having the predetermined frequency but an open state with respect to the electric current having a frequency that is an odd multiple of the predetermined frequency. In the integrated circuit, the frequency that is the odd multiple thereof is processed by only the capacitor.

Integrated circuit amplifier

A metal semiconductor device, in which an electrode is formed on a semiconductor substrate to form a Schottky junction therebetween, and the electrode has an oxide film having a first thickness on its upper surface and a non-oxidized portion having a second thickness from the Schottky junction. A method for producing the metal semiconductor device is also disclosed, in which a conductor layer formed on the semiconductor substrate is oxidized in a gas containing oxygen, and a capless annealing of the semiconductor substrate having the oxidized conductor layer thereon is conducted in an atmosphere containing arsenic.

Growing community of inventors

Ebina, Japan

Masami Nagaoka