Electron transport through a few-donor cluster flanked by acceptors is studied by first-principles and semi-empirical simulations in gated Si-nanowire transistors with n + electrostatically-doped source/drain. Local density-of-states spectra are probed by electrical characteristics at room temperature for clarifying modifications induced by acceptor-atoms on the energy states of the few-donor cluster. It is found that acceptor-atoms located between the few-donor cluster and the leads mainly shift the cluster potential, introducing a minor distortion to its energy spectrum. The results change only weakly as the acceptor-atoms are moved towards the Si nanowire surface, and systematically depend on the number of acceptors.

As CMOS device is scaling down significantly, the sensitivity of Integrated Circuits (ICs)

No abstract

No abstract

Silicon (Si) nano-electronics is advancing towards the end of the Moore’s Law, as gate lengths of just a few nanometers have been already reported in state-of-the-art transistors. In the nanostructures that act as channels in transistors or depletion layers in pn diodes, the role of dopants becomes critical, since the transport properties depend on a small number of dopants and/or on their random distribution. Here, we present the possibility of single-charge tunneling in codoped Si nanodevices formed in silicon-on-insulator films, in which both phosphorus (P) donors and boron (B) acceptors are introduced intentionally. For highly doped pn diodes, we report band-to-band tunneling (BTBT) via energy states in the depletion layer. These energy states can be ascribed to quantum dots (QDs) formed by the random distribution of donors and acceptors in such a depletion layer. For nanoscale silicon-on-insulator field-effect transistors (SOI-FETs) doped heavily with P-donors and also counter-doped with B-acceptors, we report current peaks and Coulomb diamonds. These features are ascribed to single-electron tunneling (SET) via QDs in the codoped nanoscale channels. These reports provide new insights for utilizing codoped silicon nanostructures for fundamental applications, in which the interplay between donors and acceptors can enhance the functionalities of the devices.