placing first semiconductor dies to a semiconductor wafer comprising second semiconductor dies, the semiconductor wafer comprising a semiconductor substrate and an interconnect structure disposed on the semiconductor substrate;

forming grooves on the semiconductor wafer, the grooves extending through the interconnect structure, and the semiconductor substrate being revealed by the grooves;

forming an insulating encapsulation over the semiconductor wafer to laterally encapsulate the first semiconductor dies and fill the grooves; and

performing a wafer sawing process to saw the insulating encapsulation and the semiconductor wafer along the grooves, wherein a portion of the insulating encapsulation remains on sidewalls of the interconnect structure after performing the wafer sawing process.