Green ceramic via metallization technique

摘要

The present invention provides a method for metallizing vias in co-fired ceramic green tape. A vacuum operated pick and place anvil comprising a porous block is used to pick up conductor balls from a bed. Air pressure is used to create a vacuum which pulls the conductor balls to the porous block. A stencil having openings is placed on a contact surface of the anvil, thereby permitting only one conductor ball to attach to each opening in the stencil. With the conductor balls attached to the anvil, the anvil is lowered onto the green tape. Next the anvil pushes the conductor balls into the tape until the conductor balls break through the opposite side of the tape. The anvil is retracted leaving the conductor balls lodged in the tape. It is possible to provide a green tape with pre-formed vias so that forcing the conductor balls into the tape is a simpler task. The locations of the openings in the stencil determines the location of the vias or must correspond to the vias in a tape having pre-formed vias. If the conductor balls protrude from any surface of the tape, the anvil or similar device can be used to flatten the protrusion.