A semiconductor package includes at least one second semiconductor chip stacked on a first semiconductor chip. An underfill layer is interposed between the first semiconductor chip and the at least one second semiconductor chip. The first semiconductor chip includes a first substrate, a first passivation layer disposed on the first substrate. The first passivation layer includes a first recess region. A first pad covers a bottom surface and sidewalls of the first recess region. The at least one second semiconductor chip includes a second substrate, a second passivation layer disposed adjacent to the first substrate, a conductive bump protruding outside the second passivation layer towards the first semiconductor chip and an inter-metal compound pattern disposed in direct contact with both the conductive bump and the first pad. The underfill layer is in direct contact with both the conductive bump and the inter-metal compound pattern.