After a gate electrode is formed on a main surface of a semiconductor substrate, low concentration layers are formed on the main surface of the semiconductor substrate by implanting impurities therein, with using the gate electrode as a mask. Thereafter, first sidewalls and second sidewalls are formed on the both side surfaces of the gate electrode. Subsequently, nitrogen or the like is ion-implanted into the semiconductor substrate, with using the first sidewalls, the second sidewalls and the gate electrode as a mask, thereby forming a crystallization-control region (CCR) on the main surface of the semiconductor substrate. Then, after the second sidewalls are removed, high concentration layers for a source and a drain are formed on the main surface of the semiconductor substrate.