Semiconductor devices and methods of manufacture thereof are disclosed. A preferred embodiment includes providing a workpiece having a first orientation and at least one second orientation. The semiconductor device is implanted with a dopant species using a first implantation process in the first orientation of the workpiece. The semiconductor device is implanted with the dopant species using a second implantation process in the at least one second orientation of the workpiece, wherein the second implantation process is different than the first implantation process.