Abstract: A leadframe structure for use with an integrated circuit chip, comprising a chip mount pad having an area smaller than said chip intended for mounting; a plurality of support members, each attached externally to the perimeter of said pad and internally to said leadframe; and each said support member having at least one portion located within the perimeter of said chip in a configuration operable to absorb thermally induced deformations of said support member.

Abstract: A leadframe structure for use with an integrated circuit chip, comprising a chip mount pad having an area smaller than said chip intended for mounting; a plurality of support members, each attached externally to the perimeter of said pad and internally to said leadframe; and each said support member having at least one portion located within the perimeter of said chip in a configuration operable to absorb thermally induced deformations of said support member.

Abstract: A substrate for solder ball assembling a semiconductor device substantially parallel onto said substrate, said device having a plurality of terminals arrayed on a warped surface, comprising an electrically insulating surface including a plurality of discrete metallic areas; said areas having locations matching the locations of said device terminals, and further being suitable for solder ball attachment in surface mount reflow operation; and said areas further having at least one characteristic suitable for accommodating said device warping in solder reflow operation, whereby areas having higher amounts of said characteristic cause said solder balls to become thinner during reflow, resulting in lower solder joint heights, relative to the heights of the remaining solder joints.