Damage accumulation during ion implantation of unstrained Si sub 1 minus x Ge sub x alloy layers

Journal Article · Mon Jul 06 04:00:00 EDT 1992 · Applied Physics Letters; (United States)

DOI:https://doi.org/10.1063/1.107669· OSTI ID:7070554

Haynes, T E; Holland, O W ^[1]

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1. Solid State Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6048 (United States)

The growth of damage induced by ion implantation in unstrained Si{sub 1{minus}x}Ge{sub x} epilayers is examined as a function of epilayer composition and of implant temperature and dose rate. Relaxed, epitaxial layers having compositions {ital x}=0.15, 0.50, and 0.80 were implanted with {sup 30}Si{sup +} ions at energies of 80--90 keV, doses of 1 and 6{times}10{sup 14}/cm{sup 2}, and temperatures between {minus}100 and +140 {degree}C. Damage in the implanted layers was measured by ion channeling at room temperature (RT). For RT implantation, the amount of ion-induced damage increased with Ge fraction {ital x} at a rate much greater than expected from calculations of the displacement rate. In addition, the damage growth was suppressed in each of these alloys as the implantation temperature was increased such that over a range of ion doses, the damage yield approached zero at a temperature, {ital T}{sub 0}, which increased with the Ge fraction, {ital x}. Furthermore, the damage was found to become strongly dependent on the dose rate at elevated implantation temperatures near {ital T}{sub 0}. Based upon comparisons to a simple model, these observations suggest that increasing the Ge fraction progressively reduces the mobilities of primary defects within the collision cascades.

• DOE Contract Number: AC05-84OR21400
• OSTI ID: 7070554
• Journal Information: Applied Physics Letters; (United States), Journal Name: Applied Physics Letters; (United States) Vol. 61:1; ISSN APPLA; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360605* -- Materials-- Radiation Effects
ALLOY SYSTEMS
ALLOYS
BINARY ALLOY SYSTEMS
CHARGED PARTICLES
CHEMICAL COMPOSITION
DEFECTS
EPITAXY
GERMANIUM ALLOYS
GROWTH
ION IMPLANTATION
IONS
PHYSICAL RADIATION EFFECTS
RADIATION EFFECTS
SILICON ALLOYS
SILICON IONS
TEMPERATURE DEPENDENCE