Stacked semiconductor system having interposer of half-etched and molded sheet metal
A semiconductor system ( 900 ) has a flat interposer ( 510 ) with a first surface ( 401 a ) in a first plane, a second surface ( 401 b ) in a parallel second plane, and a uniform first height ( 401 ) between the surfaces; the interposer is patterned in metallic zones separated by gaps ( 412, 415 ), the zones include metal of the first height and metal of a second height ( 402 ) smaller than the first height; an insulating material fills the gaps and the zone differences between the first and the second heights. Semiconductor chips of a first ( 610 ) and a second ( 611 ) set have first terminals attached to metallic zones of the first interposer surface while the chips of the second set have their second terminals facing away from the interposer. A first leadframe ( 700 ) is attached to the second terminals of the second set chips, and a second leadframe ( 800 ) is attached to respective metallic zones of the second interposer surface.
1. An interposer for semiconductor devices comprising:
a sheet having a first surface in a first plane for attachment to at least one semiconductor die, a second surface in a parallel second plane for attachment to a lead frame, and a uniform first height between the surfaces;
the sheet patterned in metallic zones separated by gaps, the zones including at least a first metallic zone having a metal of the uniform first height across the entire first metallic zone, and at least a second metallic zone having the metal of a first height and a second height, the second height being smaller than the first height, and the uniform first height equal to the first height; and
an insulating material filling the gaps and an area between the first and the second heights.
2. The interposer of claim 1 wherein the metal is selected from the group consisting of copper, aluminum, iron-nickel alloys, and Kovar™.
3. The interposer of claim 1 wherein the insulating material is a molding compound.
4. The interposer of claim 1 wherein the first height is between about 100 and 300 μm.
5. The interposer of claim 1 , wherein the sheet is a generally flat sheet.
6. An interposer for semiconductor devices comprising:
a plurality of conductive zones, including at least a first zone having a metal of a uniform height, and at least a second zone having the metal of a first height and a second height, the second height being smaller than the first height and the first height equal to the uniform height; and
a plurality of insulating zones defined in between the plurality of conductive zones, and in an area between the first and the second heights;
wherein a lead frame is attached to the interposer.
7. The interposer of claim 6 , wherein the plurality of insulating zones includes a molding compound.
8. The interposer of claim 6 , wherein the metal is selected from the group consisting of copper, aluminum, iron-nickel alloy, and Kovar™.