The present application discloses a semiconductor device. The semiconductor device includes a package structure including a first side and a second side opposite to the first side; an interposer structure positioned over the first side of the package structure; a first die positioned over the interposer structure; a second die positioned over the interposer structure; and a plurality of bottom interconnectors positioned on the second side of the package structure, and respectively including: a bottom exterior layer positioned on the second side of the to package structure; and a cavity enclosed by the bottom exterior layer.