In this paper, the impact of hot-carrier (HC)-induced interface damage and its spatial location on RF noise in 0.18-mum NMOSFETs have been characterized and analyzed. The experimental results revealed a significant increase in NF <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">min</sub> and R <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">n</sub> , which could be attributed to the additional channel noise component associated with the HC-induced interface damage. It is found that the presence of interface states at the source side has greater impact on the increase in channel noise, which is consistent with the recent theoretical simulation using the hydrodynamic and full Langevin-Boltzmann equation noise models based on impedance field representation. Our results provide direct experimental verification that the local noise at the source side plays a more important role in determining the overall channel noise.