A memory unit includes a resistive sense memory cell configured to switch between a high resistance state and a low resistance state upon passing a current through the resistive sense memory cell and a semiconductor transistor in electrical connection with the resistive sense memory cell. The semiconductor transistor includes a gate element formed on a substrate. The semiconductor transistor includes a source contact and a bit contact. The gate element electrically connects the source contact and the bit contact. The resistive sense memory cell electrically is connected to the bit contact. The source contact is more heavily implanted with dopant material then the bit contact.