A chip package and a method of fabricating the same are disclosed. The chip package includes a substrate with a first region, a second region surrounding the first region, and a third lane region surrounding the second region, a device layer disposed on the substrate, a via layer disposed on the device layer, an interconnect structure disposed on the via layer, and a stress buffer layer with tapered side profiles disposed on the interconnect structure. First and second portions of the via layer above the first and second regions include first and second set of vias. First, second, and third portions of the interconnect structure above the first, second, and third regions include conductive lines connected to the devices, a first set of dummy metal lines connected to the second set of vias, and a second set of dummy metal lines.