AVS 50th International Symposium
    Semiconductors Tuesday Sessions
       Session SC-TuM

Paper SC-TuM6
Stress Evolution and Nitrogen Incorporation in GaAsN Films Grown by Reactive Molecular Beam Epitaxy

Tuesday, November 4, 2003, 10:00 am, Room 321/322

Session: Narrow Gap Semiconductors
Presenter: M. Reason, University of Michigan
Authors: M. Reason, University of Michigan
W. Ye, University of Michigan
X. Weng, University of Michigan
G. Obeidi, University of Michigan
V. Rotberg, University of Michigan
R.S. Goldman, University of Michigan
Correspondent: Click to Email
Narrow gap nitride semiconductors have shown significant promise for a wide range of applications including long-wavelength light-emitters, high performance electronic devices, and high efficiency solar cells. A consequence of the large N-As size difference is a predicted limited miscibility on the anion sublattice, which often leads to the formation of GaN-rich nanostructures.@footnote 1,2@ In the case of dilute GaAs@sub 1-x@N@sub x@, conflicting results have been reported regarding the mechanism of N incorporation, and recent optical studies have suggested that the shear deformation potential and/or the binary elastic constants have an unusual composition dependence.@footnote 3@ To date, studies of stress evolution in GaAsN have been limited to x-ray rocking curves (XRC), typically interpreted using a linear interpolation of elastic constants. We have investigated stress evolution in GaAsN films, using a combination of in-situ and ex-situ measurements. A comparison of Nuclear Reaction Analysis and Rutherford Backscattering Spectrometry in channeling and non-channeling conditions suggests significant composition-dependent incorporation of N into non-substitutional sites. Furthermore, a comparison of stresses measured via in-situ wafer curvature measurements, with those determined using a Vegard's Law interpretation of XRC, suggests a change in the mechanism of N incorporation for x@>=@0.015. The observed stress differences are likely the signature of significant bowing of the elastic properties of GaAsN. This work was supported in part by the DOE (Photovoltaics Beyond the Horizon Program), the Air Force Office of Scientific Research (MURI Program), and the TRW Foundation. @FootnoteText@@footnote 1@R.S. Goldman et al., Appl. Phys. Lett. 69, 3698 (1996), J. Electr. Mater. 26, 1342 (1997). @footnote 2@X. Weng, S.J. Clarke, W. Ye, R.S. Goldman, et al, J. Appl. Phys. 92, 4012 (2002). @footnote 3@Y. Zhang, A. Mascarenhas, H.P. Xin, and C.W. Tu, Phys. Rev. B 61, 4433 (2000).