Using Monte Carlo simulation, device performance of double gate MOSFET with 25 nm-gate length is evaluated. The influences of the body thickness, of the gate overlap or underlap, of the oxide thickness, of the back gate length, and of the RC parasitic effects have been investigated. We show that well-tempered devices with excellent subthreshold behaviour and good dynamic operation may be achieved with 10 run-thick body if the gate-source/drain overlap is reduced to 0 and parasitic RC effects are controlled. To boost performance and to obtain greater allowance to parasitic RC effects, strained body may be used. Finally, the scaling strategy resulting from the study of 25 nm-long devices is successfully applied to design double gate MOSFET with shorter gate lengths. (c) 2007 Elsevier Ltd. All rights reserved.