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Title: Termination of Ge surfaces with ultrathin GeS and GeS 2 layers via solid-state sulfurization
Reactions of Ge with S vapor, of interest as a potential approach for forming thin passivation layers on Ge surfaces, have been studied by photoelectron spectroscopy and Raman spectroscopy. Exposure of Ge(100) and Ge(111) to S drives the formation of Ge sulfide near-surface layers. At low temperatures, the reaction products comprise a thin GeS interlayer terminated by near-surface GeS 2 . Above 400 °C, exposure to sulfur gives rise to single-phase GeS 2 layers whose thickness increases with temperature. Arrhenius analysis of the GeS 2 thickness yields an activation energy (0.63 ± 0.08) eV, close to the barrier that controls Ge oxidation by O radicals. XPS measurements after extended ambient exposure show a stable, ultrathin near-surface GeS 2 without significant oxidation, indicating that Ge–sulfides may provide an effective surface passivation for Ge surfaces.  more » « less
Award ID(s):
1607795
PAR ID:
10155311
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Physical Chemistry Chemical Physics
Volume:
19
Issue:
48
ISSN:
1463-9076
Page Range / eLocation ID:
32473 to 32480
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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