Effects of Co-doping on the Transport Characteristics of Nanoscale n-type Silicon-on-Insulator Transistors

In conventional downscaled Si transistors, the role of discrete dopants in nano-channels becomes critical; uniform high doping is desirable. Even in such highly-doped transistors, however, quantum dots formed by clusters of donors may work for single-electron tunneling (SET), and can be further assisted by co-doping. Here, we first analyze transport characteristics of co-doped Si nanowires by simulations, extending then the analysis to experiments on co-doped SOI-FETs with nanoscale channels. SET behavior is reported, and B-acceptors may contribute to the formation of tunnel barriers in such channels, suggesting a simple technique for Si SET devices.