A 2D simulation code resolving the Schrodinger and Poisson equations coupled with the ballistic transport equation in double-gate (DG) devices has been developed. This code has been used to investigate the operation of DG metal-oxide-semiconductor field-effect transistors (MOSFETs) in the decananometer range (5-20 nm) with ultrathin gate oxides and film bodies (1.5 nm). Particular emphasis is on the impact of quantum tunneling on the DG MOSFET scaling in terms of short-channel effects, off-state current, and subthreshold slope. (C) 2003 The Electrochemical Society.