Semiconductor packages and methods of forming the same are disclosed. One of the methods includes the following steps. A first die is provided, wherein the first die comprises a first substrate, a first interconnect structure over the first substrate, and a first pad disposed over and electrically connected to the first interconnect structure. A first bonding dielectric layer is formed over the first die to cover the first die. By using a single damascene process, a first bonding via penetrating the first bonding dielectric layer is formed, to electrically connect the first interconnect structure.