Method to improve crystalline regrowth

The migration of dislocations into pristine single crystal material during crystal growth of an adjacent conductive strap is inhibited by a conductive barrier formed at the interface between the layers. The conductive barrier may be formed by implanting carbon impurities or depositing Si:C layer that inhibits dislocation movement across the barrier layer, or by forming a passivation layer by annealing in vacuum prior to deposition of amorphous Si to prevent polycrystalline nucleation at the surface of single crystalline Si, or by implanting nucleation promoting species to enhance the nucleation of polycrystalline Si away from single crystalline Si.