Characterization of Highly Concentrated Bi Donors Wire-δ-Doped in Si

This is the authors' abstract. We don't add key points for this paper.

We studied the Bi wire-δ-doping process to achieve a high concentration of Bi donors in Si. Our process has two steps: (i) burial of Bi nanowires in Si by molecular beam epitaxy, and (ii) activation of Bi atoms in the δ-doped layer by laser annealing. The peak concentration of Bi atoms in the δ-doped layer is controlled by two parameters: the coverage of surfactant layer, and the growth temperature during the Si cap-layer growth, whose maximum concentration is larger than 10 20 cm -3 . Photoluminescence and electrical carrier transport measurements reveal that dense Bi atoms are activated upon heating the area at close to the melting point of Si. As a result, our doping process results in Bi donors in the wire-δ-doped layer with concentration of >10 18 cm -3 . This will be useful for establishing next-generation, quantum information processing platform.