Semiconductor device having planarized passivation layer and method of fabricating the same

A semiconductor device includes a semiconductor substrate divided into a pad region and a cell region and having an active surface and an inactive surface opposite to the active surface, a plurality of metal lines on the active surface of the semiconductor substrate, passivation layers on the active surface of the semiconductor substrate, and a plurality of bumps in the cell region. The passivation layers include a first passivation layer covering the plurality of metal lines and having a non-planarized top surface along an arrangement profile of the plurality of metal lines, and a second passivation layer on the non-planarized top surface of the first passivation layer and having a planarized top surface on which the plurality of bumps are disposed.