Incorporation of nitrogen in nitride-arsenides: Origin of improved luminescence efficiency after anneal

Journal Article · Sun Apr 15 04:00:00 EDT 2001 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.1352675· OSTI ID:40204942

Spruytte, Sylvia G; Coldren, Christopher W; Harris, James S; Wampler, William; Krispin, Peter; Ploog, Klaus; Larson, Michael C

A key to the utilization of nitride-arsenides for long wavelength optoelectronic devices is obtaining low defect materials with long nonradiative lifetimes. Currently, these materials must be annealed to obtain device quality material. The likely defect responsible for the low luminescence efficiency is associated with excess nitrogen. Photoluminescence and capacitance--voltage measurements indicate the presence of a trap associated with excess nitrogen which decreases in concentration upon anneal. Our films are grown by elemental source molecular beam epitaxy and the background impurity concentration is low, thus we have investigated the role of crystalline defects. High resolution x-ray diffraction showed improved crystal quality after anneal. We observed that the lattice parameter does not decrease linearly with nitrogen concentration for levels of nitrogen above 2.9 mol% GaN. The fact that Vegard's law is not observed, despite theoretical calculations that it should, indicates that nitrogen incorporates in locations other than the group V lattice sites. X-ray photoelectron spectroscopy revealed that nitrogen exists in two bonding configurations in not-annealed material: a Ga--N bond and another nitrogen complex in which N is less strongly bonded to gallium atoms. Annealing removes this second nitrogen complex. A combined nuclear reaction analysis and channeling technique showed that not annealed GaNAs contains a significant concentration of interstitial nitrogen that disappears upon anneal. We believe that this interstitial nitrogen is responsible for the deviation from Vegard's law and the low luminescence efficiency of not annealed GaNAs and GaInNAs quantum wells.

• Sponsoring Organization: (US)
• OSTI ID: 40204942
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 8 Vol. 89; ISSN 0021-8979
• Publisher: The American Physical Society
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
EFFICIENCY
LATTICE PARAMETERS
LUMINESCENCE
MOLECULAR BEAM EPITAXY
NITROGEN
NUCLEAR REACTION ANALYSIS
ORIGIN
PHOTOELECTRON SPECTROSCOPY
X-RAY DIFFRACTION