Patent ID: 11398414

Abstract:
Heat dissipation techniques include using metal features having one or more slanted or otherwise laterally-extending aspects. The metal features include, for example, tilted metal pillars, or metal bodies or fillets having an angled or sloping sidewall, or other metal features that extend both vertically and laterally. Such metal features increase the effective heat transfer area significantly by spreading heat in the in-plane (lateral) direction, in addition to the vertical direction. In some embodiments, slanted trenches are formed in photoresist/mold material deposited over a lower die, using photolithography and a multi-angle lens, or by laser drilling mold material deposited over the lower die. The trenches are then filled with metal. In other embodiments, metal features are printed on the lower die, and then molding material is deposited over the printed features. In any such cases, heat is conducted from a lower die to an upper die and/or an integrated heat spreader.