When a trench that penetrates a semiconductor substrate in a scribe region in a solid-state imaging element of a back side illumination type, occurrence of contamination of the solid-state imaging element caused by an etching step for foaming the trench or a dicing step for singulating a semiconductor chip is prevented. When a silicide layer that covers a surface and the like of an electrode of a transistor is formed, in order to prevent formation of the silicide layer that covers a main surface of the semiconductor substrate in the scribe region, the main surface of the semiconductor substrate is covered with an insulation film before a forming step for the silicide layer.

A laser crystallization method includes forming a plurality of first protrusions and depressions on a surface of an amorphous silicon layer, wherein a first protrusion and an adjacent first depression of the plurality of first protrusions and depressions, together, have a first pitch, and irradiating the amorphous silicon layer with a laser beam to form a polycrystalline silicon layer.

A semiconductor device is provided. The semiconductor device includes a semiconductor substrate, a P-well and an N-well disposed in the semiconductor substrate, a source disposed in the N-well and a drain disposed in the P-well, a shallow trench isolation (STI) structure disposed in the P-well, a gate structure disposed on the semiconductor substrate, wherein a portion of the gate structure extends into the semiconductor substrate and is disposed in a location corresponding to the STI structure.