Abstract
We have studied PHEMTs optimization by means of fabrication of PHEMTs. All PHEMTs have been fixed with a gate length of 0.1 ${\mu}{\textrm}{m}$, a gate head size of 0.75${\mu}{\textrm}{m}$, and two gate fingers. We have measured the characteristics of PHEMTs with variation of source-drain spacing, pad size, and gate width. As a result, we have found the enhanced characteristics of $I_{dss}$, $S_{21}$, $h_{21}$, $f_{T}$, $f_{max}$, and $G_{ms}$ with increasing gate width. Also, $g_{m}$ has improved with decreasing source-drain spacing, and $S_{21}$ has improved with deceasing pad size.e.e.e.e.