Back to results
US 7,294,928 B2Granted
Components, methods and assemblies for stacked packages
AssigneeTessera, Inc.
InventorsKyong-Mo Bang, David Gibson, Young-Gon Kim, John B. Riley
Life of this patent
Estimating the term…
Abstract
A bottom unit including a bottom unit semiconductor chip is mounted to a circuit board and one or more top elements such as packaged semiconductor chips are mounted to the bottom unit. Both mounting operations can be performed using the same techniques as commonly employed for mounting components to a circuit board. Ordinary packaged chips can be employed as the top elements, thereby reducing the cost of the assembly and allowing customization of the assembly by selecting packaged chips. The assembly achieves benefits similar to those obtained with a preassembled stacked chip unit, but without the expense of special handling of the bare dies included in the packaged chips.
Claims26
A semi-finished circuit board assembly comprising:
- (a) a circuit board having a top surface and contact pads exposed at said top surface;
- (b) a bottom unit including at least one bottom unit chip, said bottom unit having mounting connections facing downwardly toward said circuit board and top connections facing upwardly away from said circuit board, at least some of said mounting connections being aligned with at least some of said contact pads, at least some of said top connections being unoccupied and available to receive one or more additional microelectronic elements, at least some of the unoccupied top connections of said bottom unit overlying at least one said bottom unit chip,
- wherein said bottom unit includes a substrate incorporating a dielectric element having an upper surface facing upwardly away from said circuit board and a lower surface facing downwardly toward said circuit board, a plurality of mounting pads exposed at the lower surface of said dielectric element and a plurality of top connection pads exposed at the top surface, said at least one bottom unit chip being mounted beneath said lower surface, said mounting connections including said mounting pads, said top connections including said top connection pads.
A multichip assembly comprising:
- (a) a bottom unit including at least one bottom unit semiconductor chip, said bottom unit having downwardly-facing mounting pads and upwardly-facing top connection pads;
- (b) mounting masses of a fusible electrically conductive bottom bonding material disposed in contact with said mounting pads;
- (c) a first packaged semiconductor chip having terminals overlying at least some of said top connection pads;
- (d) a top conductive bonding material connecting at least some of said top connection pads and at least some of said terminals of said first packaged semiconductor chip;
- and
- (e) a circuit panel having a top surface and contact pads exposed at said top surface, said mounting masses bonding said mounting pads and said contact pads of said circuit panel,
- said top conductive bonding material having lesser height than said mounting masses.
4 more elements
An assembly comprising:
- (a) a bottom unit including a first bottom unit semiconductor chip, a substrate having a portion extending over said bottom unit semiconductor chip, upwardly-facing top connection pads and downwardly-facing mounting pads on said substrate, at least some of said top connection pads being disposed in said portion of said substrate, said mounting pads being adapted for connection to contact pads on a circuit board, said bottom unit semiconductor chip being permanently connected to said substrate;
- and
- (b) a first top microelectronic element at least partially overlying said portion of said substrate and said bottom unit chip, said top microelectronic element being removably mounted to said substrate and connected to said top connection pads.
An assembly including:
- (a) a bottom unit semiconductor chip having a front surface, a rear surface and edges extending between said surfaces;
- (b) a substrate having a central portion extending above said bottom unit semiconductor chip, said bottom unit semiconductor chip being mounted to said central portion of said substrate with a surface of the chip facing upwardly toward the substrate, said substrate also having one or more peripheral portions projecting outwardly beyond the edges of the chip;
- (c) first and second top microelectronic elements disposed above said substrate so that the first and second top microelectronic elements overlie different areas of said substrate, at least one of said top microelectronic elements extending over said central portion and at least one of said top microelectronic elements extending over said peripheral portion;
- and
- (d) mounting terminals on said substrate electrically connected to at least one of said chips and adapted for mounting said substrate to a circuit board,
- wherein said bottom unit semiconductor chip has greater surface area than either of said first and second top microelectronic elements alone.
3 more elements
Dependencies are inferred from the claim text.