The influence of positive bias temperature instability(PBTI)on 1/f noise performance is systematically investigated on n-channel fin field-effect transistor(FinFET).The FinFET with long and short channel(L = 240 nm,16 nm respectively)is characterized under PBTI stress from 0 s to 104 s.The 1/f noise features are analyzed by using the unified physical model taking into account the contributions from the carrier number and channel mobility fluctuations.The Id-Vg,Id-Vd,Ig-Vg tests are conducted to support and verify the physical analysis in the PBTI process.It is found that the influence of the channel mobility fluctuations may not be neglected.Due to the mobility degradation in a short-channel device,the noise level of the short channel device also degrades.Trapping and trap generation regimes of PBTI occur in high-k layer and are identified based on the results obtained for the gate leakage current and 1/f noise.