Stacked semiconductor die assemblies with thermal spacers and associated systems and methods
Stacked semiconductor die assemblies with thermal spacers and associated systems and methods are disclosed herein. In one embodiment, a semiconductor die assembly can include a thermally conductive casing defining a cavity, a stack of first semiconductor dies within the cavity, and a second semiconductor die stacked relative to the stack of first dies and carried by a package substrate. The semiconductor die assembly further includes a thermal spacer disposed between the package substrate and the thermally conductive casing. The thermal spacer can include a semiconductor substrate and plurality of conductive vias extending through the semiconductor substrate and electrically coupled to the stack of first semiconductor dies, the second semiconductor die, and the package substrate.
1. A semiconductor die assembly, comprising:
a thermally conductive casing having a sidewall, wherein thermally conductive casing defines a cavity;
a stack of first semiconductor dies within the cavity;
a second semiconductor die mechanically and electrically coupled to the stack of first dies, the second semiconductor die having a face facing the toward the stack of first semiconductor dies, wherein the sidewall of the thermally conductive casing is attached directly to the face of the second semiconductor die by a thermal adhesive;
a package substrate carrying the second semiconductor die; and
a thermal spacer disposed between the package substrate and the thermally conductive casing, wherein the thermal spacer includes a semiconductor substrate and plurality of conductive vias extending through the semiconductor substrate and electrically coupled to the stack of first semiconductor dies, the second semiconductor die, and the package substrate.
2. The semiconductor die assembly of claim 1 wherein the thermal spacer is configured to transfer heat such that individual first semiconductor dies operate at a lower heat than without the thermal spacer.
3. The semiconductor die assembly of claim 1 wherein the thermal spacer is configured to electrically couple the second semiconductor die to the stack of first semiconductor dies without processing any signals communicated through the thermal spacer.
4. The semiconductor die assembly of claim 1 wherein the thermal spacer does not include memory nor logic circuitry.
5. The semiconductor die assembly of claim 1 wherein the thermal spacer is disposed within the cavity and between the second semiconductor die and the stack of first semiconductor dies.
6. The semiconductor die assembly of claim 1 wherein the thermal spacer is disposed outside of the cavity and between the second semiconductor die and the package substrate.
7. The semiconductor die assembly of claim 1 wherein the thermal spacer comprises a blank silicon die.
8. The semiconductor die assembly of claim 1 wherein the thermal spacer is disposed in the cavity, and wherein the die assembly further comprises an underfill material at least partially encapsulating the thermal spacer and the stack of first semiconductor dies.
9. The semiconductor die assembly of claim 1 wherein the thermal spacer includes conductive features attached to the plurality of conductive vias at one or more sides of the thermal spacer, and wherein the die assembly further comprises an underfill material at least partially encapsulating the conductive features.
10. The semiconductor die assembly of claim 9 wherein the conductive features are further attached to either the second semiconductor die or the stack of first semiconductor dies.
11. The semiconductor die assembly of claim 1 wherein:
the thermal spacer is a first thermal spacer;
the semiconductor die assembly further comprises a second thermal spacer stacked relative to and electrically coupled to the first thermal spacer; and
the first and second thermal spacers are disposed between the stack of first semiconductor dies and the second semiconductor die.
12. The semiconductor die assembly of claim 1 wherein:
the thermal spacer is a first thermal spacer;
the semiconductor die assembly further comprises a second thermal spacer stacked relative to and electrically coupled to the first thermal spacer;
the first thermal spacer is disposed between the second semiconductor die and the stack of first semiconductor dies; and
the second thermal spacer is disposed between the second semiconductor die and the package substrate.
13. A semiconductor die assembly, comprising:
a thermally conductive casing, wherein the thermally conductive casing defines a cavity;
a stack of first semiconductor dies within the cavity;
a second semiconductor die mechanically and electrically coupled to the stack of first dies;
a package substrate carrying the second semiconductor die; and
a thermal spacer disposed between the package substrate and the thermally conductive casing, wherein the thermal spacer includes a semiconductor substrate and plurality of conductive vias extending through the semiconductor substrate and electrically coupled to the stack of first semiconductor dies, the second semiconductor die, and the package substrate;
wherein the stack of first semiconductor dies has a first footprint;
wherein the second semiconductor die has a second footprint larger than the first footprint, wherein the second semiconductor die has a peripheral region extending laterally outward with respect to the stack of first semiconductor dies;
wherein the thermal spacer has a third footprint that is at least as large as the first footprint along at least one axis, but no larger than the second footprint along the at least one axis.
14. A semiconductor die assembly, comprising:
a logic die having a face;
a memory die stacked relative to the logic die;
a thermally conductive casing extending at least partially around the memory die and at least partially enclosing the memory die within an enclosure, wherein the thermally conductive casing has a sidewall attached directly to the face of the logic die by a thermal adhesive;
a thermal spacer outside of the enclosure, wherein the thermal spacer includes a peripheral portion extending beyond the memory die, and the thermal spacer is configured to carry the thermally conductive casing proximate the peripheral portion.
15. The semiconductor die assembly of claim 14 wherein the logic die and the thermal spacer have generally the same planform shape.
16. The semiconductor die assembly of claim 14 wherein the logic die has a generally larger planform shape than the thermal spacer.
17. The semiconductor die assembly of claim 14 wherein the logic die is disposed within the enclosure and between the thermal spacer and the memory die.
18. The semiconductor die assembly of claim 14 wherein the logic die has a generally larger planform shape than the memory die, but a generally smaller planform shape than the thermal spacer.
19. The semiconductor die assembly of claim 14 , further comprising a package substrate configured to carry the thermal spacer, wherein the thermal spacer and the package substrate have generally the same planform shape.
20. The semiconductor die assembly of claim 14 wherein the memory die is one of a plurality of memory dies electrically coupled together in a stack.
21. A semiconductor system, comprising:
a package substrate;
a thermally conductive casing having a conductive sidewall;
a plurality of semiconductor dies configured to be carried by the package substrate and at least partially disposed within the thermally conductive casing, the plurality of semiconductor dies including a plurality of memory dies, a logic die having a face, and a thermal spacer stacked relative the logic die and the memory dies, wherein the memory dies are stacked relative to the logic die; and
a driver electrically coupled to the plurality of semiconductor dies via the package substrate;
wherein the conductive sidewall is attached directly to the face of the logic die by a thermal adhesive.