Suppressing the parasitic bipolar action of ultra-thin SOI MOSFET´s using back-side-bias-temperature treatment

A new suppression method for parasitic bipolar action is presented for fully depleted surface-channel nMOSFET´s on SOI by using the back-side-bias-temperature (BSBT) treatment technique. This method improves subthreshold characteristics, source-drain breakdown voltage, and hot-carrier instability without degrading device characteristics. BSBT treatment can suppress the parasitic bipolar action regardless of stress bias polarity. BSBT damage to the back-side interface between buried oxide and active silicon layer was investigated using several methods. The suppression mechanism proposed is the generation of fixed charges and interface traps at the back-side interface.