METHOD OF FILLING PIERCING HOLE OR NON-PIERCING HOLE FORMED IN MULTILAYER CIRCUIT BOARD OR WAFER WITH FILLER

摘要

PROBLEM TO BE SOLVED: To provide a method of perfectly filling fine holes in a multilayer circuit board or a wafer with a liquid viscous material or the melt of a low-melting-point alloy, wherein each of the holes even has a hole diameter of 25 micrometers or smaller and an aspect ratio of 5 or higher.;SOLUTION: The method of filling piercing holes or non-piercing holes formed in a multilayer circuit board or a wafer with a filler is constituted such that the filler is mimeographically printed on the multilayer circuit board or a wafer under vacuum atmosphere, and thereafter the atmosphere is changed to have the atmospheric pressure or a pressure that exceeds the atmospheric pressure, and the holes are filled with the filler utilizing the differential pressure, while an ultrasonic vibration is applied to the multilayer circuit board or to the wafer throughout the mimeogaphic printing process and the differential pressure filling process. The candidates for the filler include a liquid viscous material, a low-melting-point alloy powder, and a low-melting-point alloy melt.;COPYRIGHT: (C)2007,JPO&INPIT