Abstract: The direct tunneling current of a short channel MOSFET with a HALO structure is investigated, and a new direct tunneling gate current model is obtained.It is found that the extension regions of the gate/source and gate/drain decrease the direct tunneling gate current density because the flat band voltage between the gate/source and gate/drain is higher than that of the substrate.The extension regions reduce direct tunneling current continuously as the channel length decreases.A new direct tunneling gate current model is obtained by comparing the simulation and experimental results.This model is applicable to the devices with an ultra thin gate oxide (2～4nm),a short channel (0.13～0.25μm),and a HALO structure.

Key words: nMOSFET, HALO structure, direct tunneling current, source/drain extension region