Method and apparatus for depositing conductive paste in circuitized substrate openings

摘要

A method and apparatus for depositing conductive paste in openings of a circuitized substrate such as a multilayered printed circuit board to produce effective conductive thru-holes capable of being electrically coupled to selected conductive layers of the substrate. The invention comprises using vacuum to draw from the underside of the substrate while substantially simultaneously applying the paste onto the substrate's opposing surface. One example of means for accomplishing such paste application is a squeegee, and in one embodiment, two such squeegees may be used. A porous member is used to engage the substrate's undersurface during the vacuum draw, this member being positioned atop a base vacuum member through which the vacuum is drawn.