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.

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 hybrid bonding structure and a semiconductor including the hybrid bonding structure are provided. The hybrid bonding structure includes a solder ball and a solder paste bonded to the solder ball. The solder paste may include solder particles including at least one of In, Zn, SnBiAg alloy, or SnBi alloy, and ceramic particles. The solder paste may include a flux. The solder particles may include Sn(42.0 wt %)-Ag(0.4 wt %)-Bi(57.5−X) wt %, and the ceramic particles include CeO.sub.2(X) wt %, where 0.05≤X≤0.1.

A hybrid bonding structure and a semiconductor including the hybrid bonding structure are provided. The hybrid bonding structure includes a solder ball and a solder paste bonded to the solder ball. The solder paste may include solder particles including at least one of In, Zn, SnBiAg alloy, or SnBi alloy, and ceramic particles. The solder paste may include a flux. The solder particles may include Sn(42.0 wt %)-Ag(0.4 wt %)-Bi(57.5−X) wt %, and the ceramic particles include CeO.sub.2(X) wt %, where 0.05≤X≤0.1.