A power semiconductor module which is one of semiconductor devices includes a laminated substrate, a semiconductor chip, a housing, and terminals. The laminated substrate is formed by laminating, for example, a circuit board, an insulating plate, and a metal plate in order. Also, the semiconductor chip is electrically and mechanically connected to one region of the circuit board by a joining material. Also, the housing houses a metal substrate and the semiconductor chip, and the inside of the housing is filled with a seal material. One end of each of the terminals is electrically and mechanically connected to each of electrodes and the circuit board, which are provided on the front surface of the semiconductor chip, by respective joining materials, and the other end of the terminals is led outside the housing. The joining materials are, for example, solder.
The power semiconductor module has roughly two types of terminals, and one of them is a main terminal. The main function of the main terminal is to cause a main current to flow by way of the semiconductor chip or the like. The other is a control terminal, which is also called a sense terminal. The main function of the control terminal is to input a control signal into the semiconductor chip and to lead a temperature detection signal.
The sectional area of a portion of the main terminal joined to the circuit board has a predetermined area necessary according to current rating. Also, from the viewpoint of securing reliability, the main terminal and the circuit board are soldered in a shape such that they can be sufficiently joined. Meanwhile, in the control terminal only a microcurrent flows therethrough or only a voltage is applied thereto. Because of this, the area of a portion of the control terminal joined to the front surface electrode of the semiconductor chip or to the circuit board has a predetermined area corresponding to the package shape of a product regardless of the current rating of the main current. The region of the front surface electrode of the semiconductor chip, or of the circuit board, which is joined to the terminal, has a larger area than the leading end of the terminal.
PTL 1 illustrates a terminal which is formed of a conductive plate and has a leading end folded in an L-shape. Also, PTL 2 describes a terminal which is formed of a wire pin and a cylindrical portion in which to insert the wire pin.
USPTO Backgrounds
USPTO Backgrounds