Abstract: The present invention relates to a bipolar type semiconductor having the mesh emitter structure. The centers of intersections in said mesh emitter are hollowed and thereby parts of the base region are exposed. The internal base resistance can be reduced by employing such structure. Thereby, concentration of current into the centers of intersections of said mesh emitter at the time of turn-off can be prevented and the safe operating area of said semiconductor device can be enlarged. Moreover, the fall time of pertinent semiconductor device can be curtailed by reducing an internal base resistance and thereby the switching speed can be improved. In place of hollowing the intersections of the mesh emitter, the emitter regions in said intersections may be selectively shallowed, and furthermore opposite conductivity type regions may be formed within the emitter regions of said intersections.