Morphology of the implantation-induced disorder in GaAs studied by Raman spectroscopy and ion channeling

Journal Article · Sun Jun 01 04:00:00 EDT 1997 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.55.16205· OSTI ID:530213

Desnica, U V; Desnica-Frankovic, I D; Ivanda, M; Furic, K ^[1]; Haynes, T E ^[2]

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1. R. Boskovic Institute, P.O. Box 1016, Zagreb (Croatia)
2. Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

Disorder was introduced into GaAs by implantation of {sup 30}Si{sup +}ions, using a very wide range of ion doses, dose rates, and implant temperatures, and studied by Raman scattering (RS) and Rutherford backscattering ion channeling (RBS). RS spectra were deconvoluted consistently and systematically into up to four components, one of them being an apparent background signal interpreted here as a boson peak. Arguments are given that this signal represents the second amorphous phase different from a continuous random network. An intercascade distance model (ICD) was postulated, which estimates the average distance, L{sub ICD}, between implantation-induced cascades as a function of ion dose. An analogous parameter, L{sub RBS}, was calculated from the RBS damage fraction f{sub RBS}. From RS data the correlation length L{sub RS}, representing the size of crystalline regions with preserved translational symmetry, was determined by fitting the LO signal within the spatial correlation model. All three L{close_quote}s agree nicely, proving the equivalency of the correlation length and intercascade distance. This enabled a straightforward comparison of relevant signals and a direct correlation between RS and RBS. While measure of damage in RBS (f{sub RBS}) reflects the disordered volume fraction of the implanted layer, RS measures simultaneously the lowering of the translational symmetry (an effect that prevails at lower doses) and the fraction of disordered volume (prevailing at higher doses). A considerable difference in sensitivity between RS and RBS to particular defects enabled the differentiation of six different types of implantation-introduced disorder. {copyright} {ital 1997} {ital The American Physical Society}

• Research Organization: Oak Ridge National Laboratory
• DOE Contract Number: AC05-96OR22464
• OSTI ID: 530213
• Journal Information: Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 24 Vol. 55; ISSN 0163-1829; ISSN PRBMDO
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
AMORPHOUS STATE
GALLIUM ARSENIDES
ION CHANNELING
ION IMPLANTATION
ORDER-DISORDER TRANSFORMATIONS
RAMAN SPECTROSCOPY
SILICON IONS