Abstract: A power converter that is arranged in series with a motor to form a unitary structure through which an output shaft extends is provided with a plurality of coolers and a power semiconductor module mounted on a cooling surface of at least one of the plurality of coolers to supply electric power to a motor. Each of the plurality of coolers is disposed along an extending direction radially extending from an output shaft to be perpendicular to the output shaft. The cooling surface is provided along such an extending direction.

Abstract: A method of manufacturing a semiconductor device includes: preparing a semiconductor element having a first metal layer made of first metal on a surface thereof, and a metal substrate made of second metal, the metal substrate having a fourth metal layer made of fourth metal on a surface thereof, and mounting the semiconductor element on the surface thereof; providing metal nanopaste between the first metal layer and the fourth metal layer, the metal nanopaste being formed by dispersing fine particles made of third metal with a mean diameter of 100 nm or less into an organic solvent; and heating, or heating and pressurizing the semiconductor element and the metal substrate between which the metal nanopaste is provided, thereby removing the solvent. Further, each of the first, third and fourth metals is made of any metal of gold, silver, platinum, copper, nickel, chromium, iron, lead, and cobalt, an alloy containing at least one of the metals, or a mixture of the metals or the alloys.

Abstract: A method of manufacturing a semiconductor device includes: preparing a semiconductor element having a first metal layer made of first metal on a surface thereof, and a metal substrate made of second metal, the metal substrate having a fourth metal layer made of fourth metal on a surface thereof, and mounting the semiconductor element on the surface thereof; providing metal nanopaste between the first metal layer and the fourth metal layer, the metal nanopaste being formed by dispersing fine particles made of third metal with a mean diameter of 100 nm or less into an organic solvent; and heating, or heating and pressurizing the semiconductor element and the metal substrate between which the metal nanopaste is provided, thereby removing the solvent. Further, each of the first, third and fourth metals is made of any metal of gold, silver, platinum, copper, nickel, chromium, iron, lead, and cobalt, an alloy containing at least one of the metals, or a mixture of the metals or the alloys.

Abstract: A power conversion system for converting a dc voltage to a pulsed ac voltage includes a dc voltage source providing three or more electric potentials, and a switching circuit arranged to connect one of the potentials selectively to an output terminal. A controller produces a pulsed ac output voltage at the output terminal from the potentials of the dc voltage source by controlling an on time for connecting each of the potentials to the output terminal.

Abstract: A method of manufacturing a semiconductor device includes: preparing a semiconductor element having a first metal layer made of first metal on a surface thereof, and a metal substrate made of second metal, the metal substrate having a fourth metal layer made of fourth metal on a surface thereof, and mounting the semiconductor element on the surface thereof; providing metal nanopaste between the first metal layer and the fourth metal layer, the metal nanopaste being formed by dispersing fine particles made of third metal with a mean diameter of 100 nm or less into an organic solvent; and heating, or heating and pressurizing the semiconductor element and the metal substrate between which the metal nanopaste is provided, thereby removing the solvent. Further, each of the first, third and fourth metals is made of any metal of gold, silver, platinum, copper, nickel, chromium, iron, lead, and cobalt, an alloy containing at least one of the metals, or a mixture of the metals or the alloys.

Abstract: A stacked semiconductor module encompasses (a) a upper switching element having a first semiconductor chip, a first top electrode disposed at a top surface of the first semiconductor chip, a first bottom electrode disposed at a bottom surface of the first semiconductor chip, and a first control electrode configured to control conduction between the first top and first bottom electrodes; (b) a first wiring plate disposed beneath the upper switching element, electrically connected to the first bottom electrode; and (c) a lower switching element disposed beneath the wiring plate, having a second semiconductor chip, a second top electrode disposed at a top surface of the second semiconductor chip, electrically connected to the first wiring plate, a second bottom electrode disposed at a bottom surface of the second semiconductor chip, and a second control electrode configured to control conduction between the second top and second bottom electrodes.

Abstract: A power conversion system for converting a dc voltage to a pulsed ac voltage includes a dc voltage source providing three or more electric potentials, and a switching circuit arranged to connect one of the potentials selectively to an output terminal. A controller produces a pulsed ac output voltage at the output terminal from the potentials of the dc voltage source by controlling an on time for connecting each of the potentials to the output terminal.

Abstract: A power converter that is arranged in series with a motor to form a unitary structure through which an output shaft extends is provided with a plurality of coolers and a power semiconductor module mounted on a cooling surface of at least one of the plurality of coolers to supply electric power to a motor. Each of the plurality of coolers is disposed along an extending direction radially extending from an output shaft to be perpendicular to the output shaft. The cooling surface is provided along such an extending direction.

Abstract: A stacked semiconductor module encompasses (a) a upper switching element having a first semiconductor chip, a first top electrode disposed at a top surface of the first semiconductor chip, a first bottom electrode disposed at a bottom surface of the first semiconductor chip, and a first control electrode configured to control conduction between the first top and first bottom electrodes; (b) a first wiring plate disposed beneath the upper switching element, electrically connected to the first bottom electrode; and (c) a lower switching element disposed beneath the wiring plate, having a second semiconductor chip, a second top electrode disposed at a top surface of the second semiconductor chip, electrically connected to the first wiring plate, a second bottom electrode disposed at a bottom surface of the second semiconductor chip, and a second control electrode configured to control conduction between the second top and second bottom electrodes.