Controlled Implantation of Phosphorous Atoms into a Silicon Surface Lattice with a Scanning Tunneling Microscopy Tip

Controlling the position of dopants in a silicon lattice is a fundamental technique for future electronic devices with nanometer-sized components and for quantum applications in a Si platform, such as single-atom/defect-based qubits. Here, we demonstrate a controllable method to implant phosphorous (P) atoms into the Si surface lattice through a two-step atomic manipulation procedure using a scanning tunneling microscopy tip: first, P4 molecules adsorbed on a Si(111)-7 × 7 surface are vertically picked up and dropped off at designated locations; second, a voltage pulse triggers a breakdown of the P4 molecule, resulting in a stable P structure. First-principles calculations suggest that the manipulation product consists of a single covalently bonded P atom. Spectroscopic measurements reveal a local charge redistribution of the Si dangling bond states around the final P structure. This method will be applicable for innovation in Si-based devices with precisely spaced or patterned P dopants.