Abstract: A radio-frequency power amplifier device includes an input terminal for which a first radio-frequency signal for a CDMA mode within a first frequency band and a third radio-frequency signal for a TDMA mode within the first frequency band are selectively provided, a second input terminal for which a second radio-frequency signal for a CDMA mode within a second frequency band and a fourth radio-frequency signal for a TDMA mode within the second frequency band are selectively provided, a first power amplifier unit which to amplifies the provided first radio-frequency signal, a second power amplifier unit which amplifies the provided second radio-frequency signal, a third power amplifier unit which amplifies the provided third radio-frequency signal, and a fourth power amplifier unit which amplifies the provided fourth radio-frequency signal. These power amplifier units are arranged in order of the first power amplifier unit to the fourth power amplifier unit.

Abstract: The present invention aims at providing a heterojunction bipolar transistor having improved breakdown voltage on operation for high power output, and includes: a GaAs semiconductor substrate 100; an n+-type GaAs sub-collector layer 110; an n-type GaAs collector layer 120; a p-type GaAs base layer 130; an emitter layer 140; an n-type GaAs emitter cap layer 150; and an n-type InGaAs emitter contact layer 160. The emitter layer 140 has a multilayer structure including an n-type or non-doped first emitter layer 141 and an n-type second emitter layer 142 which are laminated in sequence. The first emitter layer 141 is made of a semiconductor material including Al, while the second emitter layer 142 is made of InxGa1-xP (0<x<1).

Abstract: An electronic device includes: a plurality of RF power amplifiers; and an impedance converting circuit. The RF power amplifiers amplify RF signals having different frequencies. The impedance converting circuit receives RF signals output from output terminals of the respective RF power amplifiers at a plurality of input terminals disposed to face the respective output terminals, and performs impedance conversion.

Abstract: A high frequency device includes a transmission/reception amplifier 13 that amplifies and outputs an input signal, and a transmission/reception switch 2 that gang switches internally so that during transmission an input of the transmission/reception amplifier 13 is connected to an up mixer and an output of the transmission/reception amplifier 13 is connected to an antenna unit 5, and so that during reception the output of the transmission/reception amplifier 13 is connected to a down mixer and the input of the transmission/reception amplifier 13 is connected to the antenna unit 5.

Abstract: There is provided a bipolar transistor that enables a desirably enhanced high-frequency performance to be obtained when used as an oscillation amplifier of an oscillation circuit, and that is miniaturized and reduced in cost. A capacitance adjustment line (11) connected to a base pad (7) forms a parasitic capacitor with respect to an N+ collector substrate by interposing an insulating film (3) and an N collector substrate therebetween, thereby increasing collector-base capacitance Ccb. This capacitor is incorporated into a bipolar transistor, which functions as an oscillation amplifier and has a small transistor operation region (2), at least as a part of a balance capacitor constituting the oscillation circuit in the course of production of a semiconductor.

Abstract: A semiconductor device has a plurality of external connection lead terminals including an input lead terminal, an output lead terminal, and an RF grounding lead terminal, a heat dissipation plate connected to the RF grounding lead terminal, a semiconductor device and a printed circuit board each mounted on the heat dissipation plate, and a mold resin for sealing the semiconductor device, the printed circuit board, and the heat dissipation plate such that at least a part of the back surface of the heat dissipation plate is exposed. The semiconductor device amplifies a signal inputted to the input lead terminal and outputs the amplified signal from the output lead terminal.

Abstract: In a high-frequency power amplifier of the present invention, when a short circuit occurs between a gate or source or between a base and emitter in one of unit cells comprising a multi-cell, influence on the operations of the other normal unit cells is suppressed by a direct-current interrupting characteristic of a diode disposed for each of the unit cells.

Abstract: A semiconductor device includes a SiC substrate and an ohmic electrode, a semiconductor member including a SiC member and a SiGe member being formed between the SiC substrate and the ohmic electrode, wherein the semiconductor member is composed of a SiGe member formed on a SiC member, and the ohmic electrode is formed on the SiGe member, whereby the ohmic electrode with a low resistance can be formed on the SiC substrate without conducting a heat treatment at a high temeprature.

Abstract: There is provided a bipolar transistor that enables a desirably enhanced high-frequency performance to be obtained when used as an oscillation amplifier of an oscillation circuit, and that is miniaturized and reduced in cost. A capacitance adjustment line (11) connected to a base pad (7) forms a parasitic capacitor with respect to an N+ collector substrate by interposing an insulating film (3) and an N collector substrate therebetween, thereby increasing collector-base capacitance Ccb. This capacitor is incorporated into a bipolar transistor, which functions as an oscillation amplifier and has a small transistor operation region (2), at least as a part of a balance capacitor constituting the oscillation circuit in the course of production of a semiconductor.

Abstract: The present invention aims at providing a heterojunction bipolar transistor having improved breakdown voltage on operation for high power output, and includes: a GaAs semiconductor substrate 100; an n+-type GaAs sub-collector layer 110; an n-type GaAs collector layer 120; a p-type GaAs base layer 130; an emitter layer 140; an n-type GaAs emitter cap layer 150; and an n-type InGaAs emitter contact layer 160. The emitter layer 140 has a multilayer structure including an n-type or non-doped first emitter layer 141 and an n-type second emitter layer 142 which are laminated in sequence. The first emitter layer 141 is made of a semiconductor material including Al, while the second emitter layer 142 is made of InxGa1-xP (0<x<1).

Abstract: There is provided a bipolar transistor that enables a desirably enhanced high-frequency performance to be obtained when used as an oscillation amplifier of an oscillation circuit, and that is miniaturized and reduced in cost. A capacitance adjustment line (11) connected to a base pad (7) forms a parasitic capacitor with respect to an N+ collector substrate by interposing an insulating film (3) and an N collector substrate therebetween, thereby increasing collector-base capacitance Ccb. This capacitor is incorporated into a bipolar transistor, which functions as an oscillation amplifier and has a small transistor operation region (2), at least as a part of a balance capacitor constituting the oscillation circuit in the course of production of a semiconductor.

Abstract: A bipolar transistor includes the first group of transistors 610a, the second group of transistors 610b, the third group of transistors 610c and the fourth group of transistors 610d. The groups of transistors have unit transistors with emitters, bases and collectors that are connected electrically in parallel and the number of unit transistors is different from group to group and 2, 4, 8, and 16, respectively.

Abstract: A semiconductor device includes a SiC substrate and an ohmic electrode, a semiconductor member including a SiC member and a SiGe member being formed between the SiC substrate and the ohmic electrode, wherein the semiconductor member is composed of a SiGe member formed on a SiC member, and the ohmic electrode is formed on the SiGe member, whereby the ohmic electrode with a low resistance can be formed on the SiC substrate without conducting a heat treatment at a high temeprature.

Abstract: A semiconductor device includes a SiC substrate and an ohmic electrode, a semiconductor member including a SiC member and a SiGe member being formed between the SiC substrate and the ohmic electrode, wherein the semiconductor member is composed of a SiGe member formed on a SiC member, and the ohmic electrode is formed on the SiGe member, whereby the ohmic electrode with a low resistance can be formed on the SiC substrate without conducting a heat treatment at a high temperature.

Abstract: A high frequency device includes a transmission/reception amplifier 13 that amplifies and outputs an input signal, and a transmission/reception switch 2 that gang switches internally so that during transmission an input of the transmission/reception amplifier 13 is connected to an up mixer and an output of the transmission/reception amplifier 13 is connected to an antenna unit 5, and so that during reception the output of the transmission/reception amplifier 13 is connected to a down mixer and the input of the transmission/reception amplifier 13 is connected to the antenna unit 5.

Abstract: A bipolar transistor includes the first group of transistors 610a, the second group of transistors 610b, the third group of transistors 610c and the fourth group of transistors 610d. The groups of transistors have unit transistors with emitters, bases and collectors that are connected electrically in parallel and the number of unit transistors is different from group to group and 2, 4, 8, and 16, respectively.

Abstract: The diode of the present invention includes: a cathode electrode and an anode electrode that are disposed on a semiconductor substrate and are spaced apart from each other; and a shielding metal member placed between the cathode and anode electrodes.

Abstract: There is provided a bipolar transistor that enables a desirably enhanced high-frequency performance to be obtained when used as an oscillation amplifier of an oscillation circuit, and that is miniaturized and reduced in cost. A capacitance adjustment line (11) connected to a base pad (7) forms a parasitic capacitor with respect to an N+ collector substrate by interposing an insulating film (3) and an N collector substrate therebetween, thereby increasing collector-base capacitance Ccb. This capacitor is incorporated into a bipolar transistor, which functions as an oscillation amplifier and has a small transistor operation region (2), at least as a part of a balance capacitor constituting the oscillation circuit in the course of production of a semiconductor.

Abstract: A package according to the present invention includes: a support for mounting a semiconductor component on the upper surface thereof; a positioning control plate, which is secured to the support and includes an opening or a notch; and a lead provided on the support for establishing electrical continuity between the semiconductor component mounted on the support and an external component. The positioning control plate houses at least a lower part of the semiconductor component inside the opening or the notch, thereby controlling a position of the semiconductor component on the support.

Abstract: The diode of the present invention includes: a cathode electrode and an anode electrode that are disposed on a semiconductor substrate and are spaced apart from each other; and a shielding metal member placed between the cathode and anode electrodes.