Method of forming tapered plug-filled via in electrical interconnection
 A process for contouring a via formed in a dielectrics whereby a layer of a refractory metal is formed on the dielectric and in the via. The refractory metal layer is removed until a surface of the refractory metal within the via is below the upper surface of the dielectric. An etching process removes a portion of the dielectric and a tapered shape is formed at the intersection of the via and the upper surface of the dielectric. A second layer of metal is formed over the dielectric, with the second layer of metal extending into the vias and contacting the refractory metal with the tapered shape providing improved step coverage of the second layer of metal at the via. 
Honeywell Inc.
H Y
H01L Y10S
inventional additional
Daniel W. John B. James C.
Youngner Straight Anderson