Full-band Monte-Carlo simulations of short channel double-gate SOI nMOSFETs were used to assess possible enhancement of drain current in devices featuring a conduction band offset between the source and the channel as those obtained using non-conventional source/drain materials. We found that the coupling between carrier transport and device electrostatics tends to balance the enhancement of charge injection provided by the band discontinuity, so that the largest contribution to the current enhancement given by alternative S/D materials is due to the strain that they induce in the channel. (c) 2007 Elsevier Ltd. All rights reserved.