Abstract
In this paper, we report the effect of 90-nm-gate InAlGaN/GaN HEMTs with 40 and 100 nm GaN channel thickness. The HEMTs with 40/100 nm channel layer exhibit an I DS sat of 839/931 mA/mm, and gm of 271/250 mS/mm, respectively. These results indicate that the thin channel devices have better control on channel conductivity, resulting in a higher peak gm. As for the RF performance, the cut-off frequency (F T ) of the devices with 40/100 nm channel thickness is 112.3 GHz/94.2 GHz, respectively.