  Single electron transistor (SET) is an advanced tool to exploit in quantum
devices. Working of such devices at room-temperature is essential for practical
utilization. Dopant based single-electron devices are well studied at
low-temperature although a few devices are developed for high-temperature
operation with certain limitations. Here, we propose and theoretically exhibit
that nitrogen (N) donor in silicon is an important candidate for effective
designing of such devices. Theoretical calculation of density-of-states using
semi-empirical DFT method indicates that N-donor in silicon has deep ground
state compared to a phosphorus (P) donor. N-donor spectrum is explored in
nano-silicon along with the P-donor. Comparative data of Bohr radius of N-donor
and P-donor is also reported. The simulated current-voltage characteristics
confirm that N-doped device is better suited for SET operation at
room-temperature.
