1. Field of the Invention
Embodiments discussed herein relate to semiconductor devices.
2. Background of the Related Art
A semiconductor device called a power semiconductor module includes a semiconductor chip having formed therein semiconductor elements, such as an IGBT (Insulated Gate Bipolar Transistor), a MOSFET (Metal Oxide Semiconductor Field Effect Transistor), and an FWD (Free Wheeling Diode), and is widely used as a power conversion device.
Then, a power semiconductor module with a three-level inverter circuit is recently applied in the fields of wind power generation, solar power generation, and the like where an increase in efficiency is demanded, (e.g., see Japanese Laid-open Patent Publication No. 2006-324585).
In the power semiconductor module of Japanese Laid-open Patent Publication No. 2006-324585, when a voltage is applied from a connection terminal, a current will be output from another connection terminal through an element inside the module and through the conductive layer for wiring. Because the capacity of a current that is output in this manner is large but the current path from a portion where the current is input to a portion where the current is output is long, it is difficult to suppress the inductance of a wiring.
Moreover, because the conductive layer for wiring is needed on a laminated substrate in addition to the conductive layer for mounting an element, a laminated substrate having a larger area is needed in order to achieve an increase in current capacity. Therefore, in order to achieve an increase in capacity, an increase in size of the power semiconductor module is inevitable. Moreover, because the current path becomes longer due to an increase in size, it becomes more difficult to suppress the inductance of a wiring.