Temperature dependent contact and channel sheet resistance extraction of GaN HEMT

In this paper, we carried out a detailed characterization and evaluation of temperature sensitive on-resistance R
_ON
(T) of Gallium Nitride (GaN) based High Electron Mobility Transistors (HEMT) through DC and low frequency S-parameters measurements. The measurements are carried out at different chuck temperatures (T
_chuck
) and the R
_ON
(T) is calculated for different values of gate-source bias (V
_GS
) of AlN/GaN/AlGaN HEMT on silicon carbide (SiC) substrate. Knowing R
_ON
(T) values for different geometries of the device, we present a practical and simplified method to evaluate the temperature dependent series contact resistance R
_se
(T) and channel sheet resistance R
_sh
(T) of the technology.