K. Saghafi, M. K Moravvej-Farshi, R. Faez, A. Shahhoseini,
Volume 5, Issue 4 (December 2009)
Abstract
In this paper, we have investigated the effects of asymmetry in the source and drain capacitance of metallic island single electron transistors. By comparing the source and drain Fermi levels, in the ground and source referenced biasing configurations, with the island’s discrete charging energy levels for various gate voltages, we have derived a set of closed form equations for the device threshold voltage. Extending our technique, for the first time, we have also modeled the “kink effect” appearing in the device ID-VDS characteristic, next to the threshold voltage. To demonstrate how accurate the calculated values of the threshold and kink voltages obtained from the analytically derived formulas are, next, we have used the master equation based on the orthodox theory to simulate the device parameters, numerically. Comparisons of the numerical results, obtained from both techniques, have demonstrated the tolerances in our analytical calculations, for the worst case, are less than 1%.
S. Haji Nasiri, M. K. Moravvej-Farshi, R. Faez,
Volume 8, Issue 1 (March 2012)
Abstract
Time domain analysis of multilayer graphene nanoribbon (MLGNR) interconnects, based on transmission line modeling (TLM) using a six-order linear parametric expression, has been presented for the first time. We have studied the effects of interconnect geometry along with its contact resistance on its step response and Nyquist stability. It is shown that by increasing interconnects dimensions their propagation delays are increased and accordingly the system becomes relatively more stable. In addition, we have compared time responses and Nyquist stabilities of MLGNR and SWCNT bundle interconnects, with the same external dimensions. The results show that under the same conditions, the propagation delays for MLGNR interconnects are smaller than those of SWCNT bundle interconnects are. Hence, SWCNT bundle interconnects are relatively more stable than their MLGNR rivals.
