Provided is a semiconductor package, including a first redistribution substrate, a first semiconductor chip on the first redistribution substrate, first bumps between the first redistribution substrate and the first semiconductor chip, a conductive structure on the first redistribution substrate and spaced apart from the first semiconductor chip, a second redistribution substrate on the first semiconductor chip, second bumps between the first semiconductor chip and the second redistribution substrate, a second semiconductor chip on the second redistribution substrate, a first mold layer between the first redistribution substrate and the second redistribution substrate, and on the first semiconductor chip, and a second mold layer on the second redistribution substrate and the second semiconductor chip, and spaced apart from the first mold layer.

A method for forming a package structure includes forming an under bump metallization (UBM) layer over a metal pad and forming a photoresist layer over the UBM layer. The method further includes patterning the photoresist layer to form an opening in the photoresist layer. The method also includes forming a first bump structure over the first portion of the UBM layer. The first bump structure includes a first barrier layer over a first pillar layer. The method includes placing a second bump structure over the first bump structure. The second bump structure includes a second barrier layer over a second pillar layer. The method further includes reflowing the first bump structure and the second bump structure to form a solder joint between a first inter intermetallic compound (IMC) and a second IMC.

A method for forming a package structure includes forming an under bump metallization (UBM) layer over a metal pad and forming a photoresist layer over the UBM layer. The method further includes patterning the photoresist layer to form an opening in the photoresist layer. The method also includes forming a first bump structure over the first portion of the UBM layer. The first bump structure includes a first barrier layer over a first pillar layer. The method includes placing a second bump structure over the first bump structure. The second bump structure includes a second barrier layer over a second pillar layer. The method further includes reflowing the first bump structure and the second bump structure to form a solder joint between a first inter intermetallic compound (IMC) and a second IMC.

Microelectronic assemblies, related devices and methods, are disclosed herein. In some embodiments, a microelectronic assembly may include a package substrate having a first surface and an opposing second surface; a first die having a first surface and an opposing second surface embedded in a first dielectric layer, where the first surface of the first die is coupled to the second surface of the package substrate by first interconnects; a second die having a first surface and an opposing second surface embedded in a second dielectric layer, where the first surface of the second die is coupled to the second surface of the first die by second interconnects; and a third die having a first surface and an opposing second surface embedded in a third dielectric layer, where the first surface of the third die is coupled to the second surface of the second die by third interconnects.

Microelectronic assemblies, related devices and methods, are disclosed herein. In some embodiments, a microelectronic assembly may include a package substrate having a first surface and an opposing second surface; a first die having a first surface and an opposing second surface embedded in a first dielectric layer, where the first surface of the first die is coupled to the second surface of the package substrate by first interconnects; a second die having a first surface and an opposing second surface embedded in a second dielectric layer, where the first surface of the second die is coupled to the second surface of the first die by second interconnects; and a third die having a first surface and an opposing second surface embedded in a third dielectric layer, where the first surface of the third die is coupled to the second surface of the second die by third interconnects.

A method includes forming a solder layer on a surface of one or more chips. A lid is positioned over the solder layer on each of the one or more chips. Heat and pressure are applied to melt the solder layer and attach each lid to a corresponding solder layer. The solder layer has a thermal conductivity of ≥50 W/mK.

A method includes forming a solder layer on a surface of one or more chips. A lid is positioned over the solder layer on each of the one or more chips. Heat and pressure are applied to melt the solder layer and attach each lid to a corresponding solder layer. The solder layer has a thermal conductivity of ≥50 W/mK.

A semiconductor package includes a first semiconductor chip comprising a semiconductor substrate and a redistribution pattern on a top surface of the semiconductor substrate, the redistribution pattern having a hole exposing an inner sidewall of the redistribution pattern, a second semiconductor chip on a top surface of the first semiconductor chip, and a bump structure disposed between the first semiconductor chip and the second semiconductor chip. The bump structure is disposed in the hole and is in contact with the inner sidewall of the redistribution pattern.

A semiconductor package includes a first semiconductor chip comprising a semiconductor substrate and a redistribution pattern on a top surface of the semiconductor substrate, the redistribution pattern having a hole exposing an inner sidewall of the redistribution pattern, a second semiconductor chip on a top surface of the first semiconductor chip, and a bump structure disposed between the first semiconductor chip and the second semiconductor chip. The bump structure is disposed in the hole and is in contact with the inner sidewall of the redistribution pattern.

A semiconductor device is disclosed. The semiconductor device comprises a redistribution structure, a processor die, and a metal post. The metal post has a first end, and a second end. The metal post is connected to the redistribution structure at the first end. The first end has a first width. The second end has a second width. The metal post has a waist width. The first width is greater than the waist width. The second width is greater than the waist width. The metal post has a side surface. The side surface is inwardly curved or outwardly curved.