A device structure, along with methods of forming such, are described. The device structure includes a structure, a first passivation layer disposed on the structure, a buffer layer disposed on the first passivation layer, a barrier layer disposed on a first portion of the buffer layer, a redistribution layer disposed over the barrier layer, an adhesion layer disposed on the barrier layer and on side surfaces of the redistribution layer, and a second passivation layer disposed on a second portion of the buffer layer. The second passivation layer is in contact with the barrier layer, the adhesion layer, and the redistribution layer.