SEMICONDUCTOR DEVICE

Provided is a semiconductor device in which an intermediate potential conductor plate faces a positive conductor plate and a negative conductor plate in order to reliably reduce inductance. The semiconductor device includes: an insulating substrate (11) on which at least four semiconductor elements forming a three-level power conversion circuit are mounted; a base plate (3) on which the insulating substrate is provided; a positive conductor plate (21) with a positive DC potential which is connected to one semiconductor element among the semiconductor elements; a negative conductor plate (22) with a negative DC potential which is connected to another semiconductor element among the semiconductor elements; and an intermediate potential conductor plate (23) with an intermediate potential which is connected to the remaining two semiconductor elements among the semiconductor elements. The positive conductor plate, the negative conductor plate, and the intermediate potential conductor plate are provided on the base plate. The positive conductor plate and the negative conductor plate are arranged close to the intermediate potential conductor plate so as to face the intermediate potential conductor plate.