An IGBT comprises trenches arranged in strips, first emitter diffusion layers formed so as to extend in a direction intersecting the trenches, and contact regions formed to have a rectangular shape. The portions of the contact regions on the first emitter diffusion layers have a smaller width than the other portions, the width extending in the direction intersecting the trenches. This configuration allows for an increase in the emitter ballast resistance of the emitter diffusion layers, resulting in enhanced resistance to electrical breakdown due to short circuit.