Device, method and system to mitigate stress on hybrid bonds in a multi-tier arrangement of chiplets
Techniques and mechanisms for mitigating stress on hybrid bonded interfaces in a multi-tier arrangement of integrated circuit (IC) dies. In an embodiment, first dies are bonded at a host die each via a respective one of first hybrid bond interfaces, wherein a second one or more dies are coupled to the host die each via a respective one of the first dies, and via a respective second hybrid bond interface. Stress at one of the hybrid bond interfaces is mitigated by properties of a first dielectric layer that extends to that hybrid bond interface. In another embodiment, stress at a given one of the hybrid bond interfaces is mitigated by properties of a dummy chip—or alternatively, properties of a patterned encapsulation structure—which is formed on the given hybrid bond interface.
1. A packaged device comprising:
a host die;
a first plurality of dies each bonded at the host die via a respective hybrid bond interface of a first plurality of hybrid bond interfaces;
a second one or more dies each coupled to the host die via a respective one of the first plurality of dies, and via a respective hybrid bond interface of a second one or more hybrid bond interfaces, wherein a first tier of a multi-tier configuration of multiple dies comprises the first plurality of dies, and wherein a second tier of the multi-tier configuration comprises the second one or more dies;
an encapsulation structure comprising a first body of a first mold compound material, and a second body of a second mold compound material;
wherein:
the first mold compound material and the second mold compound material have different compositions;
the first body and the second body each extend in a region between a first die and a second die of the multiple dies;
the first tier comprises the first die and the second die; and
the first body and the second body each extend to both:
a first vertical level of the first plurality of hybrid bond interfaces; and
a second vertical level of the second one or more hybrid bond interfaces.
2. The packaged device of claim 1 , wherein, in the region, the first body adjoins each of two opposite sides of the second body.
3. The packaged device of claim 1 , wherein a contiguous portion of the encapsulation structure extends across the region to each of the first die and the second die.
4. The packaged device of claim 3 , wherein each of the first body and the second spans at least a respective 10% of a total horizontal distance in the region between the first die and the second die.
5. The packaged device of claim 1 , wherein the one of the first tier or the second tier further comprises a third die coupled to the host die via a respective hybrid bond interface;
wherein the encapsulation structure further comprises a third body of the second mold compound material;
wherein the first body further extends into a second region between the second die and the third die; and
wherein the third body extends into the second region.
6. The packaged device of claim 1 , wherein the other of the first tier or the second tier comprises a third die and a fourth die each coupled to the host die via a respective hybrid bond interface;
wherein the encapsulation structure further comprises a third body of the second mold compound material;
wherein the first body further extends into a second region between the third die and the fourth die; and
wherein the third body extends into the second region.
7. The packaged device of claim 1 , wherein a coefficient of thermal expansion (CTE) of the second mold compound material is less than 5 parts per million per degree Kelvin (ppm/° K).
8. The packaged device of claim 1 , wherein a Young's modulus of the second mold compound material is less than 100 megaPascals (MPa).
9. The packaged device of claim 1 , wherein:
the region is a first region;
the encapsulation structure further comprises a third body of the second mold compound material;
the first body and the third body each extend in a second region between a third die and a fourth die of the multiple dies;
the second tier comprises the third die and the fourth die;
the first body and the third body each extend to the second vertical level; and
the first body and the third body each span a vertical height of the second tier.