Delta-doped AlGaN/AlN/GaN microwave HFETs grown by metalorganicchemical vapour deposition |
| |
Authors: | Wong M.M. Chowdhury U. Sicault D. Becher D.T. Denyszyn J.C. Zhu T.G. Feng M. Dupuis R.D. |
| |
Affiliation: | Microelectron. Res. Center, Texas Univ., Austin, TX; |
| |
Abstract: | The performance of an innovative delta-doped AlGaN/AlN/GaN heterojunction field-effect transistor (HFET) structure is reported. The epitaxial heterostructures were grown on semi-insulating SiC substrates by low-pressure metalorganic chemical vapour deposition. These structures exhibit a maximum carrier mobility of 1058 cm2/V s and a sheet carrier density of 2.35×1013 cm-2 at room temperature, corresponding to a large ns μn product of 2.49×1016 V s. HFET devices with 0.25 μm gate length were fabricated and exhibited a maximum current density as high as 1.5 A/mm (at VG=+1 V) and a peak transconductance of gm=240 mS/mm. High-frequency device measurements yielded a cutoff frequency of ft≃50 GHz and maximum oscillation frequency fmax≃130 GHz |
| |
Keywords: | |
|
|