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.

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.

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.

Methods for die attachment of multichip and single components including flip chips may involve printing a sintering paste on a substrate or on the back side of a die. Printing may involve stencil printing, screen printing, or a dispensing process. Paste may be printed on the back side of an entire wafer prior to dicing, or on the back side of an individual die. Sintering films may also be fabricated and transferred to a wafer, die or substrate. A post-sintering step may increase throughput.

Methods for die attachment of multichip and single components including flip chips may involve printing a sintering paste on a substrate or on the back side of a die. Printing may involve stencil printing, screen printing, or a dispensing process. Paste may be printed on the back side of an entire wafer prior to dicing, or on the back side of an individual die. Sintering films may also be fabricated and transferred to a wafer, die or substrate. A post-sintering step may increase throughput.

An electroplating method that is a conventional method has had a problem that it is difficult to manufacture fine pillars without being affected by an undercut. Furthermore, an electroless plating method has had a problem that it is difficult to manufacture pillars having the same shape without any void. The inventors have performed intensive investigations to solve the above problems and, as a result, have found that fine conductive pillars with a high aspect ratio can be readily manufactured on a substrate having an electrode section in such a manner that after a conductive paste containing metal micro-particles is applied in a reduced pressure state, the conductive paste is exposed to standard pressure. The present invention has a particular effect on the manufacture of a metal pillar that is a terminal for flip-chip mounting.

An electroplating method that is a conventional method has had a problem that it is difficult to manufacture fine pillars without being affected by an undercut. Furthermore, an electroless plating method has had a problem that it is difficult to manufacture pillars having the same shape without any void. The inventors have performed intensive investigations to solve the above problems and, as a result, have found that fine conductive pillars with a high aspect ratio can be readily manufactured on a substrate having an electrode section in such a manner that after a conductive paste containing metal micro-particles is applied in a reduced pressure state, the conductive paste is exposed to standard pressure. The present invention has a particular effect on the manufacture of a metal pillar that is a terminal for flip-chip mounting.