| 主权项 |
1. A semiconductor module used in an electric power steering apparatus, the semiconductor module comprising:
a substrate made of metal; an insulating layer formed on the substrate; a plurality of wiring patterns formed on the insulating layer; a bare-chip transistor mounted on one wiring pattern among the plurality of wiring patterns via a solder; and a metal plate connector formed of a metal plate, the metal plate connector jointing an electrode formed on a top surface of the bare-chip transistor and another wiring pattern among the plurality of wiring patterns, wherein the metal plate connector includes a flat plate portion, an electrode-jointing portion that is arranged on one end side of the flat plate portion in one direction and is jointed to the electrode of the bare-chip transistor via a solder, a substrate-jointing portion that is arranged on the other end side of the flat plate portion in the one direction and is jointed to the another wiring pattern via a solder, a first coupling portion that extends downward from the one end of the flat plate portion in the one direction and couples the one end of the flat plate portion in the one direction to one end of the electrode-jointing portion, and a second coupling portion that extends downward from the other end of the flat plate portion in the one direction and couples the other end of the flat plate portion in the one direction to one end of the substrate-jointing portion to form a bridge shape, the electrode-jointing portion is formed to be bent from the first coupling portion and extend outward in the one direction, and is formed such that a distance from the flat plate portion in a direction perpendicular to the flat plate portion is, compared to at the one end of the electrode-jointing portion, larger at the other end, such that a joint surface of the electrode-jointing portion is inclined with respect to a surface to be jointed of the electrode of the bare-chip transistor, which is opposed to the joint surface, the substrate-jointing portion is formed to be bent from the second coupling portion and extend outward in the one direction, and is formed such that the distance from the flat plate portion in the direction perpendicular to the flat plate portion is, compared to at the one end of the substrate-jointing portion, larger at the other end, such that a joint surface of the substrate-jointing portion is inclined with respect to a surface to be jointed of the another wiring pattern, which is opposed to the joint surface, the joint surface of the electrode-jointing portion that is opposed to the surface to be jointed of the electrode of the bare-chip transistor and the joint surface of the substrate-jointing portion that is opposed to the surface to be jointed of the another wiring pattern include an outgas releasing mechanism that makes outgas generated from the solders molten during solder jointing of the metal plate connector be released from the solders interposed between the joint surfaces and the surfaces to be jointed by making an air bubble of the outgas move obliquely upward along the joint surfaces being inclined, and the metal plate connector further including a mechanism that makes the outgas be released from the solders interposed between the joint surfaces and the surfaces to be jointed by making the solders molten during solder jointing of the metal plate connector flow along the first coupling portion and the second coupling portion to a lower surface of the flat plate portion and by making the air bubble of the outgas move in association with flowing of the solders. |
