Abstract: A semiconductor package includes a module substrate having opposite top and bottom surfaces, a semiconductor chip provided with bumps and mounted on the top surface of the module substrate via the bumps, and a metal member having a top portion disposed at a level higher than the semiconductor chip with reference to the top surface of the module substrate and including the semiconductor chip in plan view and a side portion extending from the top portion toward the module substrate. The module substrate includes a first metal film disposed on or in at least one of the bottom surface and an internal layer of the module substrate. The first metal film is electrically connected to the bumps and reaches a side surface of the module substrate. The side portion is thermally coupled to the first metal film at the side surface of the module substrate.

Abstract: A bipolar transistor includes a collector layer, a base layer, and an emitter layer that are formed in this order on a compound semiconductor substrate. The emitter layer is disposed inside an edge of the base layer in plan view. A base electrode is disposed on partial regions of the emitter layer and the base layer so as to extend from an inside of the emitter layer to an outside of the base layer in plan view. An insulating film is disposed between the base electrode and a portion of the base layer, with the portion not overlapping the emitter layer. An alloy layer extends from the base electrode through the emitter layer in a thickness direction and reaches the base layer. The alloy layer contains at least one element constituting the base electrode and elements constituting the emitter layer and the base layer.

Abstract: A collector layer, a base layer, and an emitter layer that are disposed on a substrate form a bipolar transistor. An emitter electrode is in ohmic contact with the emitter layer. The emitter layer has a shape that is long in one direction in plan view. A difference in dimension with respect to a longitudinal direction of the emitter layer between the emitter layer and an ohmic contact interface at which the emitter layer and the emitter electrode are in ohmic contact with each other is larger than a difference in dimension with respect to a width direction of the emitter layer between the emitter layer and the ohmic contact interface.

Abstract: A semiconductor module comprises a first member including a semiconductor substrate made of a compound semiconductor and a first electronic circuit on the semiconductor substrate is mounted on a mounting surface of a module substrate, and a second member including a semiconductor layer formed of a single semiconductor thinner than the semiconductor substrate of the first member and a second electronic circuit on the semiconductor layer is bonded to an upper surface of the first member. First and second pads are respectively connected to the first electronic circuit on the first member and the second electronic circuit on the second member. A first wire connects the first pad and a substrate side pad. A second wire connects the second pad and a substrate side pad. An inter-member connection wire made of a conductor film on the first and second members connects the first and second electronic circuits.

Abstract: In a semiconductor device, plural cells are disposed side by side on a substrate in a first direction. Each of the plural cells includes a bipolar transistor, an emitter electrode contained in a base layer of the bipolar transistor as viewed from above, and a base electrode. The bipolar transistors of the plural cells are connected in parallel with each other. Among the plural cells, the breakdown resistance of at least one second cell, which is other than a first cell disposed at each end, is higher than that of the first cell. It is possible to provide a semiconductor device that can reduce the deterioration of the breakdown resistance when flip-chip mounting is employed, as well as when face-up mounting is employed.

Abstract: A semiconductor device includes an emitter electrode above an emitter layer of a bipolar transistor. An interlayer insulating film is on the emitter electrode. An emitter contact hole is in the interlayer insulating film and is surrounded by the emitter electrode when viewed in plan view. An emitter wire is on the interlayer insulating film. The emitter wire is coupled to the emitter electrode through the emitter contact hole. When viewed in plan view, the emitter electrode and the emitter contact hole are elongated in one direction. The length of the emitter contact hole is 85% or less of the length of the emitter electrode. Of two side ends of the emitter electrode, the distance from each side end to the emitter contact hole is 5% or more of the length of the emitter electrode. This configuration further enhances the temperature uniformity in the bipolar transistor in operation.

Abstract: A cavity elongated in one direction is formed in a protective film covering the conductive pattern of the topmost conductive layer of a multilayer wiring substrate. The cavity exposes part of the conductive pattern. A first via-conductor extends downward from the conductive pattern of the topmost conductive layer at least until that of a second conductive layer. Second via-conductors extend downward from the conductive pattern of the second or third conductive layer at least until that of a conductive layer one below. As viewed from above, the first via-conductor and the cavity partially overlap each other. At least two second via-conductors are disposed to sandwich the cavity therebetween. The difference between the smallest gap between the cavity and the second via-conductor at one side and that between the cavity and the second via-conductor at the other side is smaller than the smallest gap between the cavity and the second via-conductors.

Abstract: A compound semiconductor device comprises a heterojunction bipolar transistor including a plurality of unit transistors, a capacitor electrically connected between a RF input wire and a base wire for each unit transistor of the unit transistors, and a bump electrically connected to emitters of the unit transistors. The unit transistors are arranged in a first direction. The bump is disposed above the emitters of the unit transistors while extending in the first direction. The transistors include first and second unit transistors, the respective emitters of the first and second unit transistors being disposed on first and second sides, respectively, of a second direction, perpendicular to the first direction, with respect to a center line of the bump extending in the first direction. The capacitor is not covered by the bump, and respective lengths of the respective base wires connected respectively to the first and second unit transistors are different.

Abstract: A collector layer is disposed on a substrate. The collector layer is a continuous region when viewed in plan. A base layer is disposed on the collector layer. An emitter layer is disposed on the base layer. An emitter mesa layer is disposed on the emitter layer. Two base electrodes are located outside the emitter mesa layer and within the base layer when viewed in plan. The two base electrodes are electrically connected to the base layer. Two capacitors are disposed on or above the substrate. Each of the two capacitors is connected between a corresponding one of the two base electrodes and a first line above the substrate. Two resistance elements are disposed on or above the substrate. Each of the two resistance elements is connected between a corresponding one of the two base electrodes and a second line on or above the substrate.

Abstract: A collector layer, a base layer, an emitter layer, and an emitter mesa layer are placed above a substrate in this order. A base electrode and an emitter electrode are further placed above the substrate. The emitter mesa layer has a long shape in a first direction in plan view. The base electrode includes a base electrode pad portion spaced from the emitter mesa layer in the first direction. An emitter wiring line and a base wiring line are placed on the emitter electrode and the base electrode, respectively. The emitter wiring line is connected to the emitter electrode via an emitter contact hole. In the first direction, the spacing between the edges of the emitter mesa layer and the emitter contact hole on the side of the base wiring line is smaller than that between the emitter mesa layer and the base wiring line.

Abstract: An electrically conductive sub-collector layer is provided in a surface layer portion of a substrate. A collector layer, a base layer, and an emitter layer are located within the sub-collector layer when viewed in plan. The collector layer is connected to the sub-collector layer. An emitter electrode and a base electrode are long in a first direction when viewed in plan. The emitter electrode overlaps the emitter layer. The base electrode and the emitter electrode are discretely located away from each other in a second direction orthogonal to the first direction. A collector electrode is located on one side in the second direction with respect to the emitter electrode and is not located on the other side when viewed in plan. A base line is connected to the base electrode in a manner so as to adjoin a portion other than longitudinal ends of the base electrode.

Abstract: A power amplifier comprising amplifier circuits of multiple stages. Each of the amplifier circuits of multiple stages includes a bipolar transistor and a base electrode. The bipolar transistor included in each of the amplifier circuits of multiple stages includes a collector layer, a base layer placed on the collector layer, and an emitter mesa placed on part of the region of the base layer. The emitter mesa has a shape elongated in one direction in plan view. The base electrode includes a base main portion arranged in such a manner as to be separated from the emitter mesa with a gap in a direction orthogonal to a lengthwise direction of the emitter mesa in plan view. The base main portion has a shape elongated in a direction parallel to the lengthwise direction of the emitter mesa in plan view and is electrically connected to the base layer.

Abstract: An amplifier IC mounted on a multilayer board includes input, output, and common terminals. The multilayer board includes common, input, and output terminals on board side. These terminals are connected to the corresponding terminals on device side via bumps. On the lower surface of the multilayer board, a lower surface common terminal is arranged at a location overlapping the common terminal in plan view. First, second, and third via conductors are sequentially arranged toward the lower surface common terminal from the common terminal. An input via conductor is connected to the input terminal on board side. In plan view, the area of the first common via conductor is larger than any one of the areas of the second and third common via conductors and the input via conductor. In plan view, the area of bump of the common terminal is larger than the area of bump of the input terminal.

Abstract: A heterojunction bipolar transistor includes a collector layer, a base layer, and an emitter layer that are stacked on a substrate. The collector layer includes a graded semiconductor layer in which an electron affinity increases from a side closer to the base layer toward a side farther from the base layer. An electron affinity of the base layer at an interface closer to the collector layer is equal to an electron affinity of the graded semiconductor layer at an interface closer to the base layer.

Abstract: A power amplifier module includes a first substrate and a second substrate, at least part of the second substrate being disposed in a region overlapping the first substrate. The second substrate includes a first amplifier circuit and a second amplifier circuit. The first substrate includes a first transformer including a primary winding having a first end and a second end and a secondary winding having a first end and a second end; a second transformer including a primary winding having a first end and a second end and a secondary winding having a first end and a second end; and multiple first conductors disposed in a row between the first transformer and the second transformer, each of the multiple first conductors extending from the wiring layer on a first main surface to the wiring layer on a second main surface of the substrate.

Abstract: A semiconductor device has a semiconductor substrate, and multiple first bipolar transistors on the first primary surface side of the semiconductor substrate. The first bipolar transistors have a first height between an emitter layer and an emitter electrode in the direction perpendicular to the first primary surface. The semiconductor device further has at least one second bipolar transistor on the first primary surface side of the semiconductor substrate. The second bipolar transistor have a second height, greater than the first height, between an emitter layer and an emitter electrode in the direction perpendicular to the first primary surface. Also, the semiconductor has a first bump stretching over the multiple first bipolar transistors and the at least one second bipolar transistor.

Abstract: A semiconductor device includes a collector layer, a base layer, and an emitter layer that are disposed above a substrate. An emitter mesa layer is disposed on a partial region of the emitter layer. In a plan view, the base electrode is disposed in or on a region which does not overlap the emitter mesa layer. The base electrode allows base current to flow to the base layer. In the plan view, a first edge forming part of edges of the emitter mesa layer extends in a first direction, and a second edge forming part of edges of the base electrode faces the first edge. A gap between the first edge and the second edge in a terminal portion located in an end portion of the emitter mesa layer in the first direction is wider than a gap in an intermediate portion of the emitter mesa layer.

Abstract: A bipolar transistor including a first collector layer, a second collector layer, a base layer, and an emitter layer is disposed on a substrate. Etching characteristics of the second collector layer are different from etching characteristics of the first collector layer and the base layer. In plan view, an edge of an interface between the first collector layer and the second collector layer is disposed inside an edge of a lower surface of the base layer, and an edge of an upper surface of the second collector layer coincides with the edge of the lower surface of the base layer or is disposed inside the edge of the lower surface of the base layer.

Abstract: A semiconductor device includes a plurality of unit transistors that are arranged on a surface of a substrate in a first direction. Input capacitive elements are arranged so as to correspond to the unit transistors. An emitter common wiring line is connected to emitter layers of the unit transistors. A via-hole extending from the emitter common wiring line to a back surface of the substrate is disposed at a position overlapping the emitter common wiring line. A collector common wiring line is connected to collector layers of the unit transistors. The input capacitive elements, the emitter common wiring line, the unit transistors, and the collector common wiring line are arranged in this order in a second direction. Base wiring lines that connect the input capacitive elements to base layers of the corresponding unit transistors intersect the emitter common wiring line without physical contact.

Abstract: A bipolar transistor comprising a subcollector layer, and a collector layer on the subcollector layer. The collector layer includes a plurality of doped layers. The plurality of doped layers includes a first doped layer that has a highest impurity concentration thereamong and is on a side of or in contact with the subcollector layer. Also, the first doped layer includes a portion that extends beyond at least one edge of the plurality of doped layers in a cross-sectional view.