STM study of surface reconstructions of Si(111):B

Journal Article · Thu Sep 15 00:00:00 EDT 1994 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.50.7453· OSTI ID:7050724

Shen, T; Wang, C; Lyding, J W; Tucker, J R ^[1]

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1. Department of Electrical and Computer Engineering and Beckman Institute, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States)

The scanning tunneling microscope is used to study the boron-doped Si(111) surface as a function of annealing times and temperatures. The surface structure is found to be determined by the concentration of B. When the substitutional B concentration is less than 1% of the top 1[times]1 bilayer atoms, the surface is largely 7[times]7 but surrounded by adatom-covered 1[times]1 regions (which have higher B concentration). When the B concentration is more than 3%, the whole surface will be adatom-covered 1[times]1 regions including ([radical]3 [times] [radical]3 )[ital R]30[degree] structures. The ([radical]3 [times] [radical]3 )[ital R]30[degree] domains will increase with the B concentration. Because 7[times]7 can only exist in the region with low B concentration, the growth of 7[times]7 is slowed down. Further annealing at 560 [degree]C can convert 2[times]2, [ital c](4[times]2) into 7[times]7 and 9[times]9. Sides of the 7[times]7 domain preferentially grow along the three equivalent [11[bar 2]] directions. The adatom-covered 1[times]1 regions are bounded by faulted halves of the 7[times]7 domains. The dark sites of 7[times]7 are observed and counted. They are further interpreted in terms of a B substitution model. The pattern of bright and dark atoms in ([radical]3 [times] [radical]3 )[ital R]30[degree] domains is analyzed and a criterion for a B stabilized Si-([radical]3 [times] [radical]3 )[ital R]30[degree] structure is obtained.

• DOE Contract Number: FG02-91ER45439
• OSTI ID: 7050724
• Journal Information: Physical Review, B: Condensed Matter; (United States), Vol. 50:11; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
SILICON
ANNEALING
CRYSTAL DOPING
BORON ADDITIONS
CHEMISORPTION
CRYSTAL STRUCTURE
EPITAXY
INTERFACES
SCANNING ELECTRON MICROSCOPY
SUBSTOICHIOMETRY
SURFACE PROPERTIES
ALLOYS
BORON ALLOYS
CHEMICAL REACTIONS
ELECTRON MICROSCOPY
ELEMENTS
HEAT TREATMENTS
MICROSCOPY
SEMIMETALS
SEPARATION PROCESSES
SORPTION
360602* - Other Materials- Structure & Phase Studies
360606 - Other Materials- Physical Properties- (1992-)