Provided is a semiconductor package including a first bump pad on a first substrate, a second bump pad on a second substrate, a core material for reverse reflow between the first bump pad and the second bump pad, and a solder member forming a solder layer on the core material for reverse reflow. The solder member is in contact with the first bump pad and the second bump pad. Each of a first diameter of the first bump pad and a second diameter of the second bump pad is at least about 1.1 times greater than a third diameter of the core material for reverse reflow. The core material for reverse reflow includes a core, a first metal layer directly coated on the core, and a second metal layer directly coated on the first metal layer.

Provided is a semiconductor package including a first bump pad on a first substrate, a second bump pad on a second substrate, a core material for reverse reflow between the first bump pad and the second bump pad, and a solder member forming a solder layer on the core material for reverse reflow. The solder member is in contact with the first bump pad and the second bump pad. Each of a first diameter of the first bump pad and a second diameter of the second bump pad is at least about 1.1 times greater than a third diameter of the core material for reverse reflow. The core material for reverse reflow includes a core, a first metal layer directly coated on the core, and a second metal layer directly coated on the first metal layer.

The subject matter contained herein discloses methods for forming a vertical metallic pillar overlying an under bump metal pad further overlying a semiconductor substrate, and applying a discrete solder cap on a top surface of the pillar, wherein the metallic pillar is defined by at least one photoresist layer. The method includes heating a multi-element metallic paste containing a variable amount of metallic powder, a melting point depressant and a flux such that the metal powder sinters to form the metallic pillar and simultaneously adheres the metallic pillar to the underbump metal pad.

The subject matter contained herein discloses methods for forming a vertical metallic pillar overlying an under bump metal pad further overlying a semiconductor substrate, and applying a discrete solder cap on a top surface of the pillar, wherein the metallic pillar is defined by at least one photoresist layer. The method includes heating a multi-element metallic paste containing a variable amount of metallic powder, a melting point depressant and a flux such that the metal powder sinters to form the metallic pillar and simultaneously adheres the metallic pillar to the underbump metal pad.

A semiconductor package of a pin-grid-array type includes a bump pad on a first substrate, a metal socket on a second substrate, a core material for reverse reflow on the bump pad, and solder paste or a solder bump forming a solder layer on the core material for reverse reflow. The solder paste or the solder bump is in contact with the bump pad. The core material for reverse reflow and the solder paste or the solder bump bonded to the core material for reverse reflow are used as a pin and detachably attached to the metal socket. The core material for reverse reflow includes a core, a first metal layer directly coated on the core, and a second metal layer directly coated on the first metal layer.

A semiconductor package of a pin-grid-array type includes a bump pad on a first substrate, a metal socket on a second substrate, a core material for reverse reflow on the bump pad, and solder paste or a solder bump forming a solder layer on the core material for reverse reflow. The solder paste or the solder bump is in contact with the bump pad. The core material for reverse reflow and the solder paste or the solder bump bonded to the core material for reverse reflow are used as a pin and detachably attached to the metal socket. The core material for reverse reflow includes a core, a first metal layer directly coated on the core, and a second metal layer directly coated on the first metal layer.

An electrical interconnect structure includes a bond pad having a substantially planar bonding surface, and a solder enhancing structure that is disposed on the bonding surface and includes a plurality of raised spokes that are each elevated from the bonding surface. Each of the raised spokes has a lower wettability relative to a liquefied solder material than the bonding surface. Each of the raised spokes extend radially outward from a center of the solder enhancing structure.

An electrical interconnect structure includes a bond pad having a substantially planar bonding surface, and a solder enhancing structure that is disposed on the bonding surface and includes a plurality of raised spokes that are each elevated from the bonding surface. Each of the raised spokes has a lower wettability relative to a liquefied solder material than the bonding surface. Each of the raised spokes extend radially outward from a center of the solder enhancing structure.

Provided is a semiconductor package including a first bump pad on a first substrate, a second bump pad on a second substrate, a core material for reverse reflow between the first bump pad and the second bump pad, and a solder member forming a solder layer on the core material for reverse reflow. The solder member is in contact with the first bump pad and the second bump pad. Each of a first diameter of the first bump pad and a second diameter of the second bump pad is at least about 1.1 times greater than a third diameter of the core material for reverse reflow. The core material for reverse reflow includes a core, a first metal layer directly coated on the core, and a second metal layer directly coated on the first metal layer.

Provided is a semiconductor package including a first bump pad on a first substrate, a second bump pad on a second substrate, a core material for reverse reflow between the first bump pad and the second bump pad, and a solder member forming a solder layer on the core material for reverse reflow. The solder member is in contact with the first bump pad and the second bump pad. Each of a first diameter of the first bump pad and a second diameter of the second bump pad is at least about 1.1 times greater than a third diameter of the core material for reverse reflow. The core material for reverse reflow includes a core, a first metal layer directly coated on the core, and a second metal layer directly coated on the first metal layer.