A method of forming a semiconductor device includes implanting an amorphizing species into a crystalline semiconductor substrate, the substrate having a transistor gate structure formed thereupon. Carbon is implanted into amorphized regions of the substrate, with specific implant conditions tailored such that the peak concentration of carbon species coincides with the end of the stacking faults, where the stacking faults are created during the recrystallization anneal. The implanted carbon pins partial dislocations so as to prevent the dislocations from disassociating from the end of the stacking faults and moving to a region in the substrate directly below the transistor gate structure. This removes the defects, which cause device leakage fail.