Structure and method of making capped chips including vertical interconnects having stud bumps engaged to surfaces of said caps
A capped chip is provided which includes a chip and a cap member, the chip having a front surface and a plurality of bond pads exposed at the front surface, the cap member having a bottom surface facing the front surface of the chip and having a top surface opposite the front surface. A plurality of through holes extend from the bottom surface of the cap member to the top surface. The capped chip assembly further includes a plurality of metallic interconnects extending from the bond pads at least partially through the through holes, the metallic interconnects including stud bumps joined to the bond pads, the stud bumps contacting and engaging at least one of (i) the top surface of the cap member surrounding the through holes and (ii) inner surfaces of the through holes.
1. A capped chip, comprising:
a chip having a front surface and a plurality of bond pads exposed at said front surface;
a cap member having a bottom surface facing said front surface of said chip and having a top surface opposite said front surface, said bottom surface spaced from said front surface to define a void between said chip and said cap member, said cap member further having a plurality of through holes extending from said bottom surface to said top surface; and
a plurality of metallic interconnects extending from said bond pads at least partially through said through holes, said metallic interconnects including stud bumps joined to said bond pads, said metallic interconnects contacting and engaging at least one of (i) said top surface of said cap member surrounding said through holes and (ii) inner surfaces of said through holes.
2. A capped chip as claimed in claim 1 , wherein said through holes do not have solderable metallizations.
3. A capped chip as claimed in claim 1 , wherein said metallic interconnects include a seal medium having a different composition from said stud bumps, said seal medium sealing said stud bumps to said cap member.
4. A capped chip as claimed in claim 3 , wherein said seal medium includes a conductive organic material.
5. An assembly including a capped chip as claimed in claim 1 , and further comprising an interconnection element, said interconnection element including pressure contacts pressed against said stud bumps to electrically interconnect said interconnection element to said capped chip.
6. A capped chip as claimed in claim 1 , wherein said metallic interconnects are coplanar with said top surface.
7. A capped chip as claimed in claim 6 , wherein sidewalls of said through holes are oriented at an angle of about 90 degrees to said top surface.
8. An assembly including a capped chip as claimed in claim 1 , further comprising a circuit panel having a plurality of terminals, wherein said metallic interconnects are joined to said terminals of said circuit panel.
9. A capped chip as claimed in claim 1 , wherein said stud bumps consist essentially of at least one metal selected from the group consisting of gold and copper.
10. A capped chip as claimed in claim 1 , further comprising wettable metal layers overlying inner walls of said through holes, said metallic interconnects including a fusible metallic material which wets said wettable metal layers and said stud bumps.