providing a circuit board with a plurality of SIP packaging modules arranged thereon, the plurality of SIP packaging modules being packaged by a common covering layer;

cutting the covering layer to form half-cut trenches separating each of the plurality of SIP packaging modules from each other, and to form grooves in each of the plurality of SIP packaging modules, wherein each of the half-cut trenches separates two SIP packaging modules from each other, and each of the grooves separates each of a plurality of chips to be shielded in each of the SIP packaging module;

forming a metal overlay on an exposed surface of the SIP packaging module to form a conformal shielding and a compartment shielding at the same time, the metal overlay formed on an outer surface of the SIP packaging module and at positions where the half-cut trenches are located thereby constitutes the conformal shielding to prevent the SIP packaging module from external electromagnetic interference, and the metal overlay at positions where the grooves are located thereby constitutes the compartment shielding to avoid mutual interference between the plurality of chips in each of the SIP packaging; and

cutting the half-cut trenches to obtain a plurality of separated SIP packaging modules.