Disclosed technology provides a solder ball including an outer layer having a first conductive material that is solid at an operating temperature of an electronic device, and an inner region having a second conductive material that flows at the operating temperature of the electronic device, wherein the inner region is surrounded by the outer layer. A method of manufacturing a solder ball includes forming an outer layer comprising a first conductive material that is solid at an operating temperature of an electronic device, wherein the outer layer surrounds an inner region, introducing a hole into the outer layer, injecting a second conductive material through the hole of the outer layer into the inner region, wherein the second conductive material flows at the operating temperature of the electronic device, and sealing the hole of the outer layer such that the second conductive material is retained within the inner region.

A semiconductor package includes an insulating layer; first pads respectively surrounded by the insulating layer; second pads electrically connected to the first pads; solders between and connected to the first pads and the second pads, and respectively surrounded by the insulating layer, and margin portions including an insulating material, surrounding the solders, and respectively surrounded by the insulating layer.