Patent ID: 7566632
Filing Date: 2009-07-28
Classification: H01L

Abstract:
1. A method for joining semiconductor wafers, said method comprising: bonding a top of a first wafer to a temporary holder; one of creating and exposing at least one conductive thru vias on a bottom of said first wafer, wherein said thru vias comprise conductors that extend from said top of said first wafer completely through said first wafer to said bottom of said first wafer; patterning a first mask comprising one of an oxide and a nitride on said bottom of said first wafer; forming conductive key studs in locations on said first wafer as controlled by said first mask, such said key studs one of comprise said thru vias and contact said thru vias; removing said first mask to expose said key studs; forming a second mask comprising one of an oxide and a nitride on a second wafer; forming an adhesive on said second mask; patterning lock openings through said second mask and said adhesive, and into said second wafer, wherein said lock openings expose conductors within said second wafer; positioning said first wafer with respect to said second wafer such that said key studs are positioned within said lock openings and said key studs contact said conductors within said second wafer; applying heat and pressure between said first wafer and said second wafer to cause said adhesive on said second mask to bond said first wafer to said second wafer; and removing said temporary holder from said top of said first wafer.