TY - JOUR
T1 - In-situ probing of near and below sputter-threshold ion-induced nanopatterning on GaSb(1 0 0)
AU - El-Atwani, O.
AU - Allain, J. P.
AU - Ortoleva, S.
N1 - Funding Information:
This work is in part supported by the Department of Energy’s Early Career Award and the NRC Faculty Development grant . B. Heim, A. Cimaroli, D.L. Rokusek, E.K. Walker, and D. Zigon are acknowledged for assistance with LEISS and XPS analysis and experimental runs.
PY - 2012/2/1
Y1 - 2012/2/1
N2 - This work presents in-situ near and below sputter-threshold studies for GaSb(1 0 0) at energies 50, 100 and 200 eV and current densities near 50 μAcm -2. Variation of incident particle energy probes the energy deposition distribution and its relation to surface composition. In-situ analysis is conducted over irradiation modification using Ar singly-charged ions at normal incidence of the surface using complementary techniques including: X-ray photoelectron spectroscopy (XPS) and ion-scattering spectroscopy (LEISS). The former probes 1-3 nm and the latter technique probes the first 1-2 ML or 0.3-0.6 nm. Ex-situ analysis includes HR-SEM to correlated surface morphology with surface composition studied in-situ during irradiation. Results indicate ordering of nanodot formation at fluence threshold of about 10 17 cm -2. Both XPS and LEISS identify Ga 2O 3 islands formation due to GaSb chemical affinity for oxygen followed by an initial enhancement of Ga/Sb = 1.20 ratio and then a sharp drop in Ga relative concentration with LEISS reaching a Sb-dominated terminating 1-2 nm region corresponding to the implantation depth between 50 and 200 eV. XPS shows a slight enrichment of Ga in sub-surface layers that levels to a 1:1 stoichiometry of the crystalline GaSb(1 0 0) surface.
AB - This work presents in-situ near and below sputter-threshold studies for GaSb(1 0 0) at energies 50, 100 and 200 eV and current densities near 50 μAcm -2. Variation of incident particle energy probes the energy deposition distribution and its relation to surface composition. In-situ analysis is conducted over irradiation modification using Ar singly-charged ions at normal incidence of the surface using complementary techniques including: X-ray photoelectron spectroscopy (XPS) and ion-scattering spectroscopy (LEISS). The former probes 1-3 nm and the latter technique probes the first 1-2 ML or 0.3-0.6 nm. Ex-situ analysis includes HR-SEM to correlated surface morphology with surface composition studied in-situ during irradiation. Results indicate ordering of nanodot formation at fluence threshold of about 10 17 cm -2. Both XPS and LEISS identify Ga 2O 3 islands formation due to GaSb chemical affinity for oxygen followed by an initial enhancement of Ga/Sb = 1.20 ratio and then a sharp drop in Ga relative concentration with LEISS reaching a Sb-dominated terminating 1-2 nm region corresponding to the implantation depth between 50 and 200 eV. XPS shows a slight enrichment of Ga in sub-surface layers that levels to a 1:1 stoichiometry of the crystalline GaSb(1 0 0) surface.
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U2 - 10.1016/j.nimb.2011.01.067
DO - 10.1016/j.nimb.2011.01.067
M3 - Article
AN - SCOPUS:80955163931
SN - 0168-583X
VL - 272
SP - 210
EP - 213
JO - Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms
JF - Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms
ER -