A packaged radio frequency module includes a package substrate. A semiconductor die is attached to the package substrate and includes one or more radio frequency circuits fabricated therein. A molding compound encapsulates the semiconductor die. An electromagnetic shielding structure at least partially covers the molding compound, the electromagnetic shielding structure having an outer layer including cobalt. A phone board assembly can include the packaged radio frequency module attached to a printed circuit board. The packaged radio frequency module can be incorporated into a mobile device.