US Patent 9070677 Semiconductor packages including graphene layers

A semiconductor package comprises a lower package comprising a lower substrate, a lower semiconductor chip on the lower substrate, a lower graphene layer on the lower semiconductor chip, and a lower molding layer between the lower substrate and the lower graphene layer. An upper package is on the lower substrate, the upper package spaced apart from the lower package, the upper package comprising an upper substrate, an upper semiconductor chip, and an upper molding layer. Lower conductive bumps are positioned between the lower substrate and the upper substrate, the lower bumps comprising a ground bump and a signal transmitting bump.