On the correlation between the retention time of FBRAM and the low-frequency noise of UTBOX SOI nMOSFETs

In this work, the low-frequency noise of UTBOX SOI nMOSFETs developed for Floating Body RAM (FBRAM) applications is reported and compared with the corresponding retention time. A clear trend is shown, relating a high retention time with a low noise spectral density S_Id. The one decade higher spread in S_Id compared with retention time indicates that other types of traps are responsible for both parameters. From the fact that for the same noise magnitude a different retention time can be observed in UTBOX nMOSFETs with a different channel processing strongly suggests that besides traps in the silicon film and at the interface, additional factors like the lateral electric field determine hole generation in the Si body.