CROSS-REFERENCE TO RELATED APPLICATION

The present application is based on PCT filing PCT/JP2018/020825, filed May 30, 2018, the entire contents of which are incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a semiconductor module and a power conversion device, and particularly to a semiconductor module having a direct lead bonding structure and a power conversion device to which the semiconductor module is applied.

BACKGROUND ART

In recent years, from the viewpoints of long-term reliability and loss reduction for a semiconductor module, a demand for high speed driving has also been increasing. One of the solutions regarding both of these viewpoints is a direct lead bonding (DLB) structure in which a lead frame is directly joined to a semiconductor chip with a joining material such as solder.

As compared with a wire-bonding structure, the DLB structure generally allows a longer lifetime and also allows easy reduction of the parasitic inductance that hinders high speed driving, but increases design restrictions as compared with a wire-bonding structure. For example, semiconductor chips connected in parallel cause a problem that a current between the semiconductor chips connected in parallel is more likely to deviate due to influences such as different parasitic inductances in a current loop for each semiconductor chip.

PTL 1 proposes a semiconductor module for solving the above-mentioned problem. In the semiconductor module proposed in PTL 1, wiring conductors are disposed to entirely face each other to reduce the parasitic inductance and also equalize the parasitic inductance in a current loop between the semiconductor chips electrically connected in parallel, thereby equalizing the current between the semiconductor chips.

CITATION LIST

Patent Literature

PTL 1: Japanese Patent Laying-Open No. 2015-018943

SUMMARY OF INVENTION

Technical Problem

According to the conventional method, two semiconductor chips electrically connected in parallel can achieve an effect of equalizing the current between the semiconductor chips. However, three or more semiconductor chips electrically connected in parallel in the same direction may produce a portion exhibiting a too large mutual inductance or, on the contrary, may produce a portion exhibiting a too small mutual inductance. This may make it difficult to equalize the current between the semiconductor chips, which may prevent elimination of the current deviation between the semiconductor chips electrically connected in parallel.

The present invention has been made to solve the above-described problems. One object of the present invention is to provide a semiconductor module that allows elimination of current deviation between semiconductor chips. Another object of the present invention is to provide a power conversion device to which the semiconductor module is applied.

Solution to Problem

A semiconductor module according to the present invention includes a base member, a plurality of semiconductor chips, a first wiring conductor, and a second wiring conductor. The base member has a main surface and includes at least one of a conductor and an insulator. The semiconductor chips are mounted on the main surface of the base member. The first wiring conductor is electrically connected to each of the semiconductor chips in a state where the semiconductor chips are electrically connected in parallel. The second wiring conductor is electrically connected to the first wiring conductor. The first wiring conductor and the second wiring conductor include: a facing section in which the first wiring conductor and the second wiring conductor are disposed to face each other; and a non-facing section in which the first wiring conductor and the second wiring conductor are disposed not to face each other.

A power conversion device according to the present invention includes: a main conversion circuit to convert received electric power and output converted electric power, wherein the main conversion circuit includes the semiconductor module; and a control circuit to output a control signal for controlling the main conversion circuit to the main conversion circuit.

Advantageous Effects of Invention

According to the semiconductor module of the present invention, the first wiring conductor and the second wiring conductor include the facing section and the non-facing section to thereby allow equalization of the current flowing through each of the plurality of semiconductor chips.

According to the power conversion device of the present invention, the semiconductor module is provided to thereby allow equalization of the current flowing through each of the plurality of semiconductor chips.

