A comparison was made of the strain relaxation of In0.08Ga0.92As and In0.12Ga0.88As0.99N0.01 epitaxial thin films which had been grown onto GaAs(001) by means of elemental-source molecular-beam epitaxy. The epilayers were essentially identical with regard to their compressive lattice mismatch (0.62%) and thickness (600nm). The strain state of the samples was deduced by in situ substrate curvature monitoring and by ex situ X-ray diffraction and plan-view transmission electron

microscopy. A lower rate of strain relaxation, and a 25% higher residual strain were observed in the nitride. This was attributed to the presence of N interstitials in the InGaAsN epilayers and/or to higher N bond strengths.

Comparison of Strain Relaxation in InGaAsN and InGaAs Thin Films. M.Adamcyk, J.H.Schmid, T.Tiedje, A.Koveshnikov, A.Chahboun, V.Fink, K.L.Kavanagh: Applied Physics Letters, 2002, 80[23], 4357-9