Abstract: A substrate embedded with a passive device, including a substrate, on which a cavity is formed; a passive device in the cavity, the passive being pre-molded; and a conductive material for adhering the passive device to the cavity, the conductive material being laminated on the cavity.

Abstract: A method for manufacturing a substrate embedded with a passive device, comprising the steps of (a) molding the passive device and (b) mounting the molded passive device in a cavity formed on the substrate, is disclosed. The substrate embedded with a passive device and the manufacturing method thereof in accordance with the present invention can prevent warpage of the substrate caused by disproportioned properties of materials.

Abstract: Disclosed is a working panel for a multilayer printed circuit board. The working panel for a multilayer printed circuit board is constructed in a manner such that first and second strips, having circuit layers and insulating layers which are layered on the upper and lower sides of a core in the opposite order with respect to each other, are appropriately disposed, by which the working panel can resist warpage due to thermal stress applied during the substrate fabrication process, thus imparting industrially useful effects that promise improvements in the standardization, productivity and yield of products.

Abstract: Disclosed is a drill bit for making a hole through stacked PCBs includes a drill part formed with drilling edges on an outer surface thereof and brought into contact with the PCBs, that is, a workpiece in which to make the hole; a reamer part formed on the rear end of the drill part and having at least one reaming edge for finishing the surface of the hole; and a shank part formed on the rear end of the reamer part and mounted to a machine tool.