Electrical-stress-induced degradation in AlGaN/GaN high electron mobility transistors grown under gallium-rich, nitrogen-rich, and ammonia-rich conditions

We have evaluated the long-term electrical reliability of GaN/AlGaN high-electron-mobility transistors grown under Ga-rich, N-rich, and NH3-rich conditions. Vpinch-off shifts positively after stress for devices grown under Ga-rich and N-rich conditions, while it shifts negatively for NH3-rich devices. Density functional theory calculations suggest that the hot-electron-induced release of hydrogen from hydrogenated Ga-vacancies is primarily responsible for the degradation of devices grown in Ga-rich and N-rich conditions, while hydrogenated N-antisites are the dominant defects causing degradation in devices grown under NH3-rich conditions.

[1]  R. J. Shul,et al.  GAN : PROCESSING, DEFECTS, AND DEVICES , 1999 .

[2]  U. Mishra,et al.  The impact of surface states on the DC and RF characteristics of AlGaN/GaN HFETs , 2001 .

[3]  Christiane Poblenz,et al.  Structural and morphological properties of GaN buffer layers grown by ammonia molecular beam epitaxy on SiC substrates for AlGaN/GaN high electron mobility transistors , 2008 .

[4]  C. Walle,et al.  First-principles calculations for defects and impurities: Applications to III-nitrides , 2004 .

[5]  Hyungtak Kim,et al.  Hot electron induced degradation of undoped AlGaN/GaN HFETs , 2003, Microelectron. Reliab..

[6]  Ronald D. Schrimpf,et al.  Theory of hot-carrier-induced phenomena in GaN high-electron-mobility transistors , 2010 .

[7]  Christiane Poblenz,et al.  Structural Properties of GaN Buffer Layers on 4H-SiC(0001) Grown by Plasma-Assisted Molecular Beam Epitaxy for High Electron Mobility Transistors , 2004 .

[8]  P. Chao,et al.  HEMT degradation in hydrogen gas , 1994, IEEE Electron Device Letters.

[9]  P. Waltereit,et al.  Power performance of AlGaN-GaN HEMTs grown on SiC by plasma-assisted MBE , 2004, IEEE Electron Device Letters.

[10]  Steven A. Ringel,et al.  Deep level optical and thermal spectroscopy of traps in n-GaN grown by ammonia molecular beam epitaxy , 2008 .

[11]  Steven A. Ringel,et al.  Hydrogen passivation of deep levels in n–GaN , 2000 .

[12]  Christiane Poblenz,et al.  X- and Ka-band power performance of AlGaN/GaN HEMTs grown by ammonia-MBE , 2008 .