Abstract: A semiconductor device according to the present invention is a semiconductor device which includes: a semiconductor element; a gate drive circuit; and a connection terminal unit, wherein the semiconductor element includes: a gate electrode pad; and first and second ohmic electrode pads, the connection terminal includes: a first ohmic electrode terminal connected to the first ohmic electrode pad; a second ohmic electrode terminal connected to the second ohmic electrode pad; a gate drive terminal connected to the first ohmic electrode pad; and a gate terminal connected to the gate electrode pad, an input terminal of the gate drive circuit is connected to the gate drive terminal, an output terminal of the gate drive circuit is connected to the gate terminal, and a potential of the first ohmic electrode pad corresponds to a reference potential of the gate drive circuit.

Abstract: A field effect transistor includes a semiconductor stack formed on a substrate, and having a first nitride semiconductor layer and a second nitride semiconductor layer. A source electrode and a drain electrode are formed on the semiconductor stack so as to be separated from each other. A gate electrode is formed between the source electrode and the drain electrode so as to be separated from the source electrode and the drain electrode. A hole injection portion is formed near the drain electrode. The hole injection portion has a p-type third nitride semiconductor layer, and a hole injection electrode formed on the third nitride semiconductor layer. The hole injection electrode and the drain electrode have substantially the same potential.

Abstract: A two-wire AC switch suppressing heat from a bidirectional switch element inside the switch is provided. The two-wire AC switch 100a connected between an AC power supply 101 and a load 102 includes: a bidirectional switch element 103 which flows passing current bi-directionally, selects whether to flow or block the current, is connected in series with the AC power supply 101 and the load 102 to form a closed-loop circuit, and is made of a group-III nitride semiconductor; a full-wave rectifier 104 performing full-wave rectification on power supplied from the AC power supply 101; a power supply circuit 105 smoothing a voltage after the full-wave rectification to generate DC power; a first gate drive circuit 107 and a second gate drive circuit 108 each outputting a control signal to the bidirectional switch element 103; and a control circuit 106 controlling the first and second gate drive circuits 107 and 108.

Abstract: A semiconductor device includes a first transistor formed on a first element region, and a first protecting element including a second transistor formed on a second element region. A second protecting element ohmic electrode is connected to a first gate electrode, a first protecting element ohmic electrode is connected to a first ohmic electrode, and a first protecting element gate electrode is connected to at least one of the first protecting element ohmic electrode and the second protecting element ohmic electrode. The second element region is smaller in area than the first element region.

Abstract: In a high-voltage semiconductor switching element, in addition to a first emitter region that is necessary for switching operations, a second emitter region, which is electrically connected with the first emitter region through a detection resistor in current detection means and is electrically connected with the current detection means, is formed. No emitter electrode is formed on the second emitter region, while an emitter electrode is formed on a part of a base region that is adjacent to the second emitter region.

Abstract: A semiconductor device in which: reed-shaped portions of an emitter layer of a second conductivity type are discretely formed on a surface of a base layer in a first vertical direction that is a direction vertical to a direction from an emitter electrode to a collector electrode; in a region adjoining the emitter layer, an interface of the contact layer on a side of the collector electrode is formed up to directly beneath an interface of the gate electrode on a side of the emitter electrode; and directly beneath the emitter layer, the interface of the contact layer on the side of the collector electrode is formed closer to the emitter electrode than to the interface of the gate electrode on the side of the emitter electrode.

Abstract: In a base region of a first conductivity type, at least one emitter region of a second conductivity type and at least one sense region of the second conductivity type, spaced away from the emitter region, are selectively formed. The emitter region and the sense region are located so as to be aligned in a second direction perpendicular to a first direction going from a collector region of the first conductivity type, which is formed so as to be spaced away from the base region, toward the base region. The width of the sense region, the width of the emitter region, the width of a part of the base region that is adjacent to the sense region, and the width of a part of the base region that is adjacent to the emitter region in the second direction are set in such a manner that a sense ratio varies in a desired manner in accordance with variation in collector current.

Abstract: A semiconductor device includes a first diffusion region of a second conductivity type formed in an upper portion of a semiconductor substrate of a first conductivity type, a second diffusion region formed in a surface portion of the first diffusion region, a third diffusion region of the second conductivity type formed a predetermined distance spaced apart from the second diffusion region in the surface portion of the semiconductor substrate, a fourth diffusion region of the first conductivity type formed adjacent to the third diffusion region and electrically connected to the third diffusion region, a gate electrode formed on a part between the first diffusion region and the third diffusion region, and an insulating film formed thereon.

Abstract: In a base region of a first conductivity type, at least one emitter region of a second conductivity type and at least one sense region of the second conductivity type, spaced away from the emitter region, are selectively formed. The emitter region and the sense region are located so as to be aligned in a second direction perpendicular to a first direction going from a collector region of the first conductivity type, which is formed so as to be spaced away from the base region, toward the base region. The width of the sense region, the width of the emitter region, the width of a part of the base region that is adjacent to the sense region, and the width of a part of the base region that is adjacent to the emitter region in the second direction are set in such a manner that a sense ratio varies in a desired manner in accordance with variation in collector current.

Abstract: In a high-voltage semiconductor switching element, in addition to a first emitter region that is necessary for switching operations, a second emitter region, which is electrically connected with the first emitter region through a detection resistor in current detection means and is electrically connected with the current detection means, is formed. No emitter electrode is formed on the second emitter region, while an emitter electrode is formed on a part of a base region that is adjacent to the second emitter region.