A relationship between 1/f noise and DC parameters in the pHEMT at 4.2 K

According to the Hooge empirical 1/f formula, a linear relationship between the squared equivalent input 1/f noise voltage and the ratio of drain current over squared transconductance has been developed. Low-power and low-frequency noise pHEMTs with gate lengths of 4 and 1 μm have been fabricated and characterized at 4.2K. The obtained noise and DC data are in good agreement with this developed expression when drain biases are fixed in both of quasi-linear and saturation regimes. This relationship provides the possibilities to evaluate the device noise level by its DC parameters and to determine the Hooge coefficient by directly measurable parameters.