Patent ID: 7700407
Filing Date: 2010-04-20
Classification: H01L

Abstract:
1. A method of forming a bump-on-lead flip chip interconnection having improved escape routing density, comprising: providing a die; providing a package substrate having traces formed on a die attach side of the package substrate; and attaching a plurality of composite bumps to pads on an active side of the die, each composite bump including a noncollapsible bump portion and a fusible bump portion, the composite bumps being mated onto corresponding interconnect sites on the traces such that the noncollapsible bump portion extends between the pad and the trace and the fusible bump portion melts to bond the noncollapsible bump portion to the interconnect site, the interconnect sites having parallel edges defining an interconnect site width, the interconnect site width being less than a width of the composite bump mated onto the interconnect site.