Ion sputtering of GaAs(110): From individual bombardment events to multilayer removal

Journal Article · Fri Sep 01 04:00:00 EDT 1995 · Journal of Vacuum Science and Technology. B, Microelectronics Processing and Phenomena

DOI:https://doi.org/10.1116/1.588129· OSTI ID:165709

Wang, X; Pechman, R J; Weaver, J H ^[1]

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1. Department of Materials Science and Chemical Engineering, University of Minnesota, Minneapolis, Minnesota 55455 (United States)

We have investigated the effects of ion mass (Ar{sup +}, Xe{sup +}), energy (0.3--5 keV), trajectory, and sample temperature on the ion sputtering processes for GaAs(110). Scanning tunneling microscopy images reveal that most ion bombardment events at 300 K create pits that are 1--5 unit cells in size, indicating that direct knock-on collisions dominate. The average pit size increases moderately with ion energy but shows a significant variation with the incident angle. Vacancies are sufficiently mobile at 625--775 K that vacancy islands form and the yield can be determined directly. The sputtering yields for these nearly ideal surfaces exhibit structure that can be related to the nuclear stopping power and ion channeling, showing the influence of such geometric factors as surface path length, ion radius, and projected atom column density. Temperature dependent results for monolayer and multilayer sputtering show that adatoms ejected onto the surface refill vacancies but that the surface roughness, as measured by surface width, increases with ion fluence. While interlayer atomic transport is measurable at 625 K and increases with temperature, it is not sufficient to achieve layer-by-layer removal because As{sub {ital x}} desorption competes with interlayer transport above {similar_to}800 K. {copyright} {ital 1995} {ital American} {ital Vacuum} {ital Society}

• OSTI ID: 165709
• Journal Information: Journal of Vacuum Science and Technology. B, Microelectronics Processing and Phenomena, Journal Name: Journal of Vacuum Science and Technology. B, Microelectronics Processing and Phenomena Journal Issue: 5 Vol. 13; ISSN 0734-211X; ISSN JVTBD9
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
ARGON IONS
ATOM COLLISIONS
ATOM TRANSPORT
EV RANGE 100-1000
GALLIUM ARSENIDES
KEV RANGE 01-10
PHYSICAL RADIATION EFFECTS
SPUTTERING
TEMPERATURE DEPENDENCE
TEMPERATURE RANGE 0273-0400 K
TEMPERATURE RANGE 0400-1000 K
VACANCIES
XENON IONS