The effect of air/AlGaN and GaN/substrate polarization charges on the performances of GaN-based HEMTs have been investigated. We find that surface charges and, with a minor extend, GaN/substrate charges are responsible for the observed premature saturation of the dc output characteristics. Moreover, our work show that the polarization charges and holes trap appear as the source of the drain cur...

AlGaN/GaN high-electron-mobility transistors (HEMT) have been grown by radio frequency molecular beam epitaxy (RF-MBE) on 3” Si substrates. A record low contact resistance Rc ~ 0.11 .mm has been achieved for GaN HEMTs on Si by using non alloyed ohmic contacts regrown by MBE. Owing to the low contact resistance a 75-nm gate length unpassivated HEMT shows intrinsic current gain cut-off frequency ...

Acknowledgments 1 Acknowledgments I would like to acknowledge prof. Labat, prof. Nathalie Malbert and prof. André Touboul for their guidance, support, and the freedom to explore my own ideas; Alessandro Chini, prof. Gaudenzio Meneghesso, prof Enrico Zanoni and all the members of their group, as well as the members of the NNL laboratory, for the great cooperative work in Italy; Mohsine Bouya, Ar...

Submitted for the MAR08 Meeting of The American Physical Society Fabrication and characterization of InAs/AlGaSb HEMTs with high-k gate insulators TOSHIHIKO MAEMOTO, KENJI FUJIWARA, TATSUYA INOUE, NAOKI AMANO, MASATOSHI KOYAMA, SHIGEHIKO SASA, MASATAKA INOUE, OSAKA INSTITUTE OF TECHNOLOGY TEAM — We report on the fabrication and characterization of InAs/AlGaSb high electron mobility transistors ...

Depletion-mode quaternary barrier In0.13Al0.83 Ga0.04N high-electron-mobility transistors (HEMTs) with regrown ohmic contacts and T-gates on a SiC substrate have been fabricated. Devices with 40-nm-long footprints show a maximum output current density of 1.8 A/mm, an extrinsic dc transconductance of 770 mS/mm, and cutoff frequencies fT /fmax of 230/300 GHz at the same bias, which give a record-...

The heterogeneous integration of GaAs HEMTs on a polyimide-covered AlN ceramic substrate was demonstrated using a fluidic self-assembly (FSA) technique. We used thin device blocks for the FSA, which have various advantages. In particular, they can reduce the drain-source capacitance Cds of the assembled HEMTs if the substrate has a low dielectric constant. This is a novel kind of semiconductor-...

GaN-based high-electron-mobility transistors (HEMTs) are very promising candidates for the next generation of high-power and high-frequency electronics. However, trapping effects have been one of the most important barriers in the development of the GaN semiconductor since its infancy. In recent years, significant research efforts have been focused on understanding and suppressing trapping effe...

For the needs of high electron mobility transistors (HEMTs) optimization a reliable software simulation tool is required. Due to the high electric field in the device channel a hydrodynamic approach is used to properly model the electron transport. We modify an existing hydrodynamic mobility model in order to achieve a better agreement with Monte Carlo (MC) simulation data and measured DC and A...

AlGaN/GaN high electron mobility transistors (HEMTs) represent a rapidly maturing technology plagued by reliability issues which are not well understood. One such issue is the relationship between gate leakage and the formation of reaction-based defects at the interface between the gate metal and the underlying epitaxial semiconductor layers. Here, the combination of chemical etching-based depr...

GaN-based high-electron-mobility transistors (HEMTs) are very promising candidates for the next generation of high-power and high-frequency electronics. However, trapping effects have been one of the most important barriers in the development of the GaN semiconductor since its infancy. In recent years, significant research efforts have been focused on understanding and suppressing trapping effe...