We report the integration of a scanning force microscope with ion beams. The scanning probe images surface structures non-invasively and aligns the ion beam to regions of interest. The ion beam is transported through a hole in the scanning probe tip. Piezoresistive force sensors allow placement of micromachined cantilevers close to the ion beam lens. Scanning probe imaging and alignment is demonstrated in a vacuum chamber coupled to the ion beam line. Dot arrays are formed by ion implantation in resist layers on silicon samples with dot diameters limited by the hole size in the probe tips of a few hundred nm.

Spins of single donor atoms are attractive candidates for large scale quantum information processing in silicon. Formation of devices with a few qubits is crucial for validation of basic ideas and development of a scalable architecture. We describe our development of a single ion implantation technique for placement of single atoms into device structures. Collimated highly charged ion beams are aligned with a scanning probe microscope. Enhanced secondary electron emission due to high ion charge states (e.g., 31 P 13+ , or 126 Te 33+ ) allows efficient detection of single ion impacts. Studies of electrical activation of low dose, low energy implants of 31 P in silicon show a drastic effect of dopant segregation to the SiO 2 /Si interface, while Si 3 N 4 /Si retards 31 P segregation. We discuss resolution limiting factors in ion placement, and process challenges for integration of single atom arrays with control gates and single electron transistors.

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