XeF[sub 2] etching of Si(111): The geometric structure of the reaction layer

Journal Article · Tue Jun 15 04:00:00 EDT 1993 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.47.15648· OSTI ID:6397386

Lo, C W; Shuh, D K; Chakarian, V; Durbin, T D; Varekamp, P R; Yarmoff, J A ^[1]

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1. Department of Physics, University of California, Riverside, California 92521 (United States) Materials Sciences Division, Lawrence Berkeley Laboratory, Berkeley, California 94720 (United States)

Si(111)-7[times]7 is exposed to XeF[sub 2] in ultrahigh vacuum and examined with soft-x-ray photoelectron spectroscopy (SXPS) and photon-stimulated desorption (PSD). The exposures encompass the entire range from chemisorption to steady-state etching. By taking into account the different surface sensitivities of SXPS and PSD, the microscopic structure of the surface fluorosilyl reaction layer is obtained as a function of exposure, and the reaction process is modeled. It is found that the reaction-layer structure passes through four distinct exposure regimes. Steric hindrance between the F atoms of neighboring fluorosilyl groups and defects in the substrate are responsible for the evolution of the reaction-layer structure. When steady-state etching is reached, the reaction layer evolves to a tree'' structure of fluorosilyl chains terminated at the surface by SiF[sub 3] groups.

• DOE Contract Number: AC02-76CH00016
• OSTI ID: 6397386
• Journal Information: Physical Review, B: Condensed Matter; (United States), Journal Name: Physical Review, B: Condensed Matter; (United States) Vol. 47:23; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360602* -- Other Materials-- Structure & Phase Studies
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201 -- Chemical & Physicochemical Properties
CHEMICAL REACTIONS
CHEMISORPTION
ELECTRON SPECTROSCOPY
ELEMENTS
ETCHING
FLUORIDES
FLUORINE COMPOUNDS
HALIDES
HALOGEN COMPOUNDS
KINETICS
PHOTOELECTRON SPECTROSCOPY
RARE GAS COMPOUNDS
REACTION KINETICS
SEMIMETALS
SEPARATION PROCESSES
SILICON
SORPTION
SPECTROSCOPY
SURFACE FINISHING
XENON COMPOUNDS
XENON FLUORIDES