Patent ID: 6767818
Filing Date: 2004-07-27
Classification: H01L

Abstract:
A method for forming electrically conductive bumps on a wafer comprising the steps of:providing a wafer having an active surface, a plurality of conductive elements formed on the active surface, and a passivation layer insulating said plurality of conductive elements from each other, sputter depositing a first metal layer on top or said plurality of conductive elements and said passivation layer, printing a plurality of bumps of an insulating material each on top of one of said plurality of conductive elements, heat treating said plurality of bumps at a temperature of at least 100Â° C., sputter depositing a second metal layer on top of said plurality of bumps and said first metal layer, and patterning and removing said first and said second metal layer in areas in-between said plurality of bumps.