GIBART , P.

AlGaN/GaN high-electron mobility transistors (HEMTs) structures regrown by metalorganic vapour phase epitaxy (MOVPE) on semi-insulating (SI) GaN templates, after exposure to air, results in the presence of parasitic conducting channels at regrowth interface. Air contamination of the SI GaN templates generates this parallel conduction. The...

In order to get semi‐insulating GaN layers with a low dislocation density on sapphire, two kinds of Fe doping were explored by low pressure metalorganic vapour phase epitaxy (LP‐MOVPE): the modulation doping (MD) and the continuous doping (CD). The high crystalline quality and the semi‐insulating character are obtained in the case of the Fe‐MD...

New conditions for one‐step ELO were implemented to grow coalesced (11equation image0) non‐polar and (11equation image2) semi‐polar GaN layers starting, respectively, from R ‐ and M ‐plane sapphire. A great part of the stacking faults (SFs) and dislocations are filtrated resulting in GaN material with better structural and optical properties....

Highly resistive GaN (>1E+8 Ω#) is grown by MOVPE on sapphire with dislocation density in the range 1E+8 to 8E+8 /cm², using Fe modulation doping. High mobility 2DEGs are created at AlGaN/GaN:Fe interface for moderate Al composition: 2200 cm²/V/s at n_s∼7.6E+12 /cm². Good DC and RF small signal behaviour could be obtained in HEMTs processed on...

For the first time, to the knowledge of the authors, GaN MESFETs on silicon substrate have been realised using low-pressure metal-organic vapour phase epitaxy. The devices demonstrate good pinch-off voltage and good breakdown voltage characteristics. A maximum extrinsic transconductance of 30 mS/mm was achieved on a 100 * 0.5 µm2 device. At a...

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In this work, AlGaN/GaN high electron mobility transistors have been grown by ammonia source molecular beam epitaxy (MBE) on silicon (1 1 1), silicon carbide and GaN templates on sapphire. The structural and electrical properties of these layers have been studied in order to determine the impact of substrate choice and buffer layer on active...