AVS 50th International Symposium
    Semiconductors Thursday Sessions
       Session SC-ThM

Paper SC-ThM7
Characterization of High Quality GaAs(100) Films Grown on Ge(100) Substrates

Thursday, November 6, 2003, 10:20 am, Room 326

Session: Heteroepitaxy and Strain Engineering
Presenter: A. Wan, Princeton University
Authors: A. Wan, Princeton University
V.M. Menon, Princeton University
D. Wasserman, Princeton University
A. Kahn, Princeton University
S.R. Forrest, Princeton University
S.A. Lyon, Princeton University
Correspondent: Click to Email
We have grown GaAs (100) films by MBE on off-axis Ge(100) substrates cut 6° towards the (110) plane and 6º towards the (111) plane. The motivation for this work is the integration of GaAs and lattice matched InGaAsN on Si and SiGe. Vicinal surfaces with regular arrays of double steps are crucial in eliminating anti-phase domains in III-V/elemental systems.@footnote 1@ We used electron diffraction, STM, AFM, X-ray and ultraviolet photoemission, electron channeling, photoluminesence (PL) and Raman spectroscopy to investigate the quality of the GaAs films. We observed two domains (1 x 2 and 2 x 1) on the surfaces of the Ge substrates both after annealing and after Ge buffer growth, on each of the off-cut orientations. GaAs films grown on Ge substrates cut towards the (110) exhibited poor morphology, with evidence of faceting and polycrystalline domains, whereas films grown on substrates cut towards the (111) exhibited much higher crystalline quality with a (4 x 2) recontruction. Low temperature PL exhibited a sharp narrow peak at 1.51 eV on samples grown on substrates cut towards (111), indicative of high quality material. We also investigated the effects of using different growth conditions including migration enhanced epitaxy, which have been reported to reduce both the APD and doping at the GaAs/Ge.@footnote 2,3@ We conclude that high quality GaAs can be grown at a variety of growth temperatures and conditions on off axis Ge(100) substrates cut 6° towards the (111). @FootnoteText@ @footnote 1@J.M. Zhou et al., Appl. Phys Lett. 68, 628 (1996) @footnote 2@R.M. Sieg et al., J. Vac. Sci. Technol. B 16, 1471 (1998) @footnote 3@J.A. Carlin et al., Appl. Phys Lett. 76, 1884 (2000).