AlGaN/GaN MISHEMT with hBN as gate dielectric

J.C. Gerbedoen (1) , Ali Soltani (1) , M. Mattalah (1) , M. Moreau (2) , P. Thevenin (3) , Jean-Claude de Jaeger (1)

1 IEMN - Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520
2 LASIRE - Laboratoire Avancé de Spectroscopie pour les Intéractions la Réactivité et l'Environnement - UMR 8516
3 LMOPS - Laboratoire Matériaux Optiques, Photonique et Systèmes

Metal/Insulator/Semiconductor AlGaN/GaN High Electron Mobility Transistors (MISHEMTs) on sapphire substrate were fabricated with hexagonal Boron Nitride (hBN) thin film as gate dielectric. The hBN thin film, deposited by MW-PECVD, is an insulator permitting to obtain a low leakage current gate, an interface state density as low as 5 × 1011 cm⁻² eV⁻¹ for hBN/AlGaN interface and low roughness surface less than 0.4 nm. HBN thin film is deposited to have optical c-axis oriented weakly tilted to the perpendicular at the AlGaN barrier surface and to increase the lateral electrical resistivity. DC measurement on MISHEMT exhibits promising performance for microwave power devices associated to a good gate charge control in enhancement mode.

Mots clés: Gate dielectric; HBN thin film; HEMTs; MISHEMTs; Gate dielectric

Domaines: Matériaux

J.C. Gerbedoen, Ali Soltani, M. Mattalah, M. Moreau, P. Thevenin, et al.. AlGaN/GaN MISHEMT with hBN as gate dielectric. Diamond and Related Materials, 2009, 18, pp.1039 - 1042. ⟨10.1016/j.diamond.2009.02.018⟩. ⟨hal-00435395⟩