Low-frequency 1/f noise in MOSFET’s at low current levels

Abstract
Low‐frequency 1/f noise in Si n‐channel MOSFET’s is measured at 300 and 77 K. It is found that the equivalent input‐noise resistance Rng increases at low current levels from 100 to 10−2 μA in both the saturation and linear regions. A theory is developed to account for this characteristic, assuming the activated conduction at low electron concentrations due to the surface potential roughness as proposed by Chen and Muller. Theoretical calculations are made for the linear region of operation. Excellent agreement is obtained between the theory and the experiment at both temperatures.