The effect of annealing a 75nm-thick layer of indium gallium arsenide nitride (InGaAsN) in 1.0 x 10(-6) Torr of nitrogen trifluoride (NF3) has been studied by photoluminescence spectrometry, X-ray diffraction, X-ray photoelectron spectroscopy, and hydrogen adsorption infrared spectroscopy. A red shift of 25 nm in the peak was observed following heating in NF3 at 530 degrees C. The compressive strain of the InGaAsN was reduced under annealing in NF3 ambient, while it increased under annealing in AsH3 ambient. It is concluded that N atoms diffuse into the alloy during the NF3 exposure at 530 degrees C and increase the nitrogen concentration from about 1.2-1.7%. (C) 2007 Elsevier B.V. All rights reserved.