Role of lattice mismatch and surface chemistry in the formation of epitaxial semiconductor-insulator interfaces

Journal Article · Sun Apr 15 00:00:00 EDT 1990 · Physical Review, B: Condensed Matter; (USA)

DOI:https://doi.org/10.1103/PhysRevB.41.8420· OSTI ID:6836809

Olmstead, M A ^[1]; Bringans, R D ^[2]

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1. Department of Physics, University of California, Berkeley, Berkeley, California 94720 (USA)
2. Xerox Corporation, Palo Alto Research Center, 3333 Coyote Hill Road, Palo Alto, California 94304 (USA)

The formation of SrF{sub 2}/Si(111) and Ge/CaF{sub 2}/Si(111) interfaces is studied with photoemission and compared to previous results for the CaF{sub 2}/Si(111) interface. The interface between SrF{sub 2} and Si(111) is found to be nonstoichiometric, similar to the interface between CaF{sub 2} and Si(111): the bonding is between Si and the cation, with a layer of fluorine missing at the interface. In the case of Ge growth on CaF{sub 2}/Si(111), a variety of effects are noted: The CaF{sub 2}/Si(111) valence-band offset is reduced by about 1 eV upon deposition of Ge at room temperature. The sticking coefficient of the Ge is significantly increased by preparing the CaF{sub 2} surface with electron bombardment to remove the top layer of fluorine. For both the irradiated and nonirradiated cases, annealing of thin room-temperature-deposited films resulted in Ge island formation.

• OSTI ID: 6836809
• Journal Information: Physical Review, B: Condensed Matter; (USA), Vol. 41:12; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CALCIUM FLUORIDES
CHEMICAL BONDS
GERMANIUM
SILICON
STRONTIUM FLUORIDES
ANNEALING
ELECTRICAL INSULATORS
EPITAXY
INTERFACES
LATTICE PARAMETERS
MEDIUM TEMPERATURE
PHOTOEMISSION
SEMICONDUCTOR MATERIALS
STOICHIOMETRY
SURFACE PROPERTIES
VALENCE
ALKALINE EARTH METAL COMPOUNDS
CALCIUM COMPOUNDS
CALCIUM HALIDES
ELECTRICAL EQUIPMENT
ELEMENTS
EMISSION
EQUIPMENT
FLUORIDES
FLUORINE COMPOUNDS
HALIDES
HALOGEN COMPOUNDS
HEAT TREATMENTS
MATERIALS
METALS
SECONDARY EMISSION
SEMIMETALS
STRONTIUM COMPOUNDS
360602* - Other Materials- Structure & Phase Studies