Patent ID: 6163957
Filing Date: 2000-12-26
Classification: H01L,H05K,Y10S,Y10T

Abstract:
A method of making a multilayer substrate from a first circuit layer and a second circuit layer, each circuit layer having a first surface, a second surface, and at least one electrical pad disposed on its first surface, the method comprising:(a) tack laminating a bonding sheet onto the second surface of the first circuit layer by heat pressing, the bonding sheet having a first surface bonded to the second surface of the first circuit layer and a second surface, the bonding sheet further having a release layer releaseably adhered to the second surface of the bonding sheet;(b) laser drilling an aperture which passes through the release layer, the bonding sheet, and the first circuit layer and which terminates on a pad at the first surface of the first circuit layer;(c) filling the aperture with a non-volatile conductive composition with the release layer adhered to the bonding sheet, the conductive composition contacting the pad of the first circuit layer;(d) removing the release layer from the bonding sheet; and(e) laminating the bonding sheet to the first surface of the second circuit layer by heat pressing such that the aperture confronts a pad of the second circuit layer, and such that the conductive composition forms an electrical connection between the pad of the first circuit layer and the pad of the second circuit layer.