A semiconductor package includes a block having opposing first and second main surfaces and sides between the first and second main surfaces, and an encapsulation material at least partly covering the block. One or both of the main surfaces of the block has recessed regions. The recessed regions do not extend completely through the block from one main surface to the other main surface. The encapsulation material fills the recessed regions to form an interlocked connection between the block and the encapsulation material. Additional semiconductor package embodiments are provided.