The present disclosure relates to a latch-up test structure, including: a substrate of a first conductive type; a first well region of a second conductive type, located in the substrate of the first conductive type; a first doped region of the first conductive type, located in the first well region of the second conductive type; a first doped region of the second conductive type, located in the first well region of the second conductive type; and a second doped region of the first conductive type, a second doped region of the second conductive type, a third doped region of the first conductive type, and a third doped region of the second conductive type that are arranged at intervals in the substrate of the first conductive type.

The present disclosure provides a latch-up test structure, including: a substrate of a first conductive type; a first well region of the first conductive type, located in the substrate of the first conductive type; a first doped region of the first conductive type, located in the first well region of the first conductive type; a first doped region of a second conductive type, located in the first well region of the first conductive type; and a second doped region of the first conductive type, a second doped region of the second conductive type, a third doped region of the first conductive type, and a third doped region of the second conductive type that are arranged at intervals in the substrate of the first conductive type.

The present disclosure provides a latch-up test structure, including: a substrate of a first conductive type; a first well region of the first conductive type, located in the substrate of the first conductive type; a first doped region of the first conductive type, located in the first well region of the first conductive type; a first doped region of a second conductive type, located in the first well region of the first conductive type; and a second doped region of the first conductive type, a second doped region of the second conductive type, a third doped region of the first conductive type, and a third doped region of the second conductive type that are arranged at intervals in the substrate of the first conductive type.

A compound semiconductor device includes a heterojunction bipolar transistor and a bump. The heterojunction bipolar transistor includes a plurality of unit transistors. The bump is electrically connected to emitters of the plurality of unit transistors. The plurality of unit transistors are arranged in a first direction. The bump is disposed above the emitters of the plurality of unit transistors while extending in the first direction. The emitter of at least one of the plurality of unit transistors is displaced from a center line of the bump in the first direction toward a first side of a second direction which is perpendicular to the first direction. The emitter of at least another one of the plurality of unit transistors is displaced from the center line of the bump in the first direction toward a second side of the second direction.

On a single-crystal semiconductor substrate with an upper surface including a first direction in which an inverted mesa step extends and a second direction in which a forward mesa step extends in response to anisotropic etching in which an etching rate depends on crystal plane orientation, a bipolar transistor including a collector layer, a base layer, and an emitter layer that are epitaxially grown, and a base wire connected to the base layer are arranged. A step is provided at an edge of the base layer, and the base wire is extended from inside to outside of the base layer in a direction intersecting the first direction in a plan view. An intersection of the edge of the base layer and the base wire has a disconnection prevention structure that makes it difficult for step-caused disconnection of the base wire to occur.

A semiconductor structure including a substrate and a deep trench isolation structure is provided. The deep trench isolation structure is disposed in the substrate and is not electrically connected to any device. The deep trench isolation structure includes a heat dissipation layer and a dielectric liner layer. The heat dissipation layer is disposed in the substrate. The dielectric liner layer is disposed between the heat dissipation layer and the substrate.

A bipolar junction transistor is provided with an emitter structure that is positioned above the upper surface of the base region. The thickness of the emitter and the interfacial oxide thickness between the emitter and the base is configured to optimize a gain for a given type of transistor. A method of fabricating PNP and NPN transistors on the same substrate using a complementary bipolar fabrication process is provided. The method enables the emitter structure for the NPN transistor to be defined separately to that of the PNP transistor. This is achieved by epitaxially growing the emitter layer for the PNP transistor and growing the emitter layer for the NPN transistor in a thermal furnace.

For example, a semiconductor device includes one or more first subcontacts electrically conducted to a substrate. At least one of the one or more first subcontacts is formed in an element arrangement region, and has a lower impedance than the substrate. Preferably, at least one of the one or more first subcontacts is adjacent to a circuit element formed in the element arrangement region. Preferably, on the substrate, which is of a first conductivity type, an epilayer of a second conductivity type is formed, and the one or more first subcontacts include a first line having a lower impedance than the substrate, and a semiconductor region of the first conductivity type penetrating through the epilayer to electrically conduct the first line and the substrate to each other.

For example, a semiconductor device includes one or more first subcontacts electrically conducted to a substrate. At least one of the one or more first subcontacts is formed in an element arrangement region, and has a lower impedance than the substrate. Preferably, at least one of the one or more first subcontacts is adjacent to a circuit element formed in the element arrangement region. Preferably, on the substrate, which is of a first conductivity type, an epilayer of a second conductivity type is formed, and the one or more first subcontacts include a first line having a lower impedance than the substrate, and a semiconductor region of the first conductivity type penetrating through the epilayer to electrically conduct the first line and the substrate to each other.

A first sub-collector layer functions as an inflow path of a collector current that flows in a collector layer of a heterojunction bipolar transistor. A collector ballast resistor layer having a lower doping concentration than the first sub-collector layer is disposed between the collector layer and the first sub-collector layer.