ASYMMETRICAL CHARACTERISTICS OF LIGHTLY-DOPED DRAIN MOSFETS

Asymmetrical and degraded characteristics of drain-source non-overlap LDD MOSFETs resulting from shadowing effects are observed. The substrate and gate current behaviour are explained by two-dimensional simulation of the channel electric field. The lifetime of LDD devices is also tested and compared with conventional MOSFETs. The non-overlap degree and location affect the operation performance as well as the device lifetime. Experiments show that devices with source non-overlap are worse than those with drain non-overlap.