US Patent 9991226 Semiconductor packages having asymmetric chip stack structure

A semiconductor package may include first chip stack including first chips which are stacked on a package substrate and offset to form a first reverse stepwise sidewall. The semiconductor package may include a second chip stack including second chips which are stacked on the package substrate and offset to form a second reverse stepwise sidewall. The first protrusion corner of the first chip stack may protrude toward the second chip stack.