A new 2-D simulation code resolving the Schrodinger and Poisson equations coupled with the ballistic transport equation in double-gate (DG) devices has been developed. The present approach also includes the quantum mechanical tunneling of carriers through the source-to-drain barrier and the wave function penetration in the gate oxide. This code has been used to investigate the operation of DG SOI MOSFETs in the deca-nanometer range (5-20 nm) with ultrathin gate oxide and film bodies (1.5 nm). The present study particularly emphasizes on the impact of quantum tunneling on the DG SOI MOSFET scaling in terms of short-channel effects, off-state current and subthreshold slope. (C) 2003 Elsevier Science Ltd. All rights reserved.