Patent ID: 6686280
Filing Date: 2004-02-03
Classification: H01L

Abstract:
A process for filling an opening, comprising:providing an integrated circuit having an upper surface; removing a portion of said upper surface to a depth, thereby forming an opening having a bottom surface, a mouth, and side walls; depositing a first seed layer of metal to a first thickness to coat the integrated circuit upper surface, the bottom surface, and the side walls of the opening; sputter etching said first seed layer, to reduce its thickness by a first amount, thereby preferentially removing some overhanging material present at the mouth of the opening; depositing a second seed layer over said first seed layer; sputter etching said second seed layer to reduce its thickness by a second amount, thereby preferentially removing any remaining overhanging material present at the mouth of the opening; and depositing additional metal, whereby said opening becomes completely filled with void free metal.