[en] Deep submicron partially depleted silicon on insulator (PDSOI) nMOSFETs were fabricated based on the 0.35 μm SOI process developed by the Institute of Microelectronics of the Chinese Academy of Sciences (IMECAS). Mechanisms determining short-channel effects (SCE) in PDSOI nMOSFETs are clarified based on experimental results of threshold voltage dependence upon gate length. The effects of body bias, drain bias, temperature and body contact on the SCE have been investigated. The SCE in SOI devices is found to be dependent on body bias, drain bias and body contact. Floating body devices show a more severe reverse short channel effect (RSCE) than devices with body contact structure. Devices with low body bias and high drain bias show a more obvious SCE. (semiconductor devices)