Low-frequency noise degradation caused by STI interface effects in SOI-MOSFETs

Abstract

The low-frequency noise characteristics of SOI MOSFETs with shallow trench isolation (STI) structure are investigated for various device sizes with three different gate shapes. Devices with channel region butted to the STI show an increase of low-frequency noise as the channel width is reduced. In comparison, the devices without the STI butted to the channel region show much less increase of noise power spectral density with channel width. From the charge pumping and noise measurement results, the interface-state generated by the STI process is identified as the cause of these anomalous phenomena.