Possibility of Transport Through a Single Acceptor in a Gate-All-Around Silicon Nanowire PMOSFET

Abstract

Temperature-dependent electrical transport measurements of cylindrical shaped gate-all-around silicon nanowire p-channel MOSFET were performed. At 4.2 K, they show current oscillations, which can be analyzed by single hole tunneling originated from nanowire quantum dots. In addition to this single hole tunneling, one device exhibited strong current peaks, surviving even at room temperature. The separations between these current peaks corresponded to the energy of 25 and 26 meV. These values were consistent with the sum of the bound-state energy spacing and the charging energy of a single boron atom. The radius calculated from the obtained single-atom charging energy was also comparable to the light-hole Bohr radius.Index Terms-Gate-all-around (GAA), silicon nanowire FET (SNWFET), single-acceptor atom, temperature dependence.

Current-voltage spectroscopy of dopant-induced quantum-dots in heavily n-doped junctionless nanowire transistors

“…If we suppose the cross-section of initial channel is less than 2 Â 2 nm 2 , there might be 11 dopants within the conduction channel length of 280 nm. However, at very low temperatures, only fewer dopants can be ionized to work as quantum dots, 11 which are distributed randomly in the long conduction channel. To determine the exact positions of the current oscillation features, Figure 2(b) shows the curves of the transconductance g m as a function of gate voltage V g (i.e., g m ¼ @I ds =@V g ) and the gate voltage positions of the g m valleys at varying V ds .…”