The Multivalley Effective Conduction Band-Edge Method for Monte Carlo Simulation of Nanoscale Structures

Abstract

The trend toward continuous integration of the nanometer scale and the rise of nonconventional device concepts such as multigate transistors present important challenges for the semiconductor community. Simulation tools have to be adapted to this new scenario where classical approaches are not sufficiently accurate, and quantum effects have to be taken into account. This paper proposes a method of including quantum corrections in Monte Carlo (MC) simulations without solving the SchrÖdinger equation. The approach, based on the effective conduction band-edge (ECBE) method, considers the effects of an arbitrary effective mass tensor, describing valley characteristics and confinement directions while avoiding the use of effective mass as a fitting parameter. The performance of the multivalley ECBE method is tested using an ensemble MC simulator to study benchmark devices for next International Technology Roadmap for Semiconductors technological nodes, a 25-nm channel length bulk-MOSFET and a double-gate silicon-on-insulator MOSFET in both steady-state and transient situations.