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Study of patterned GaAsSbN nanowires using sigmoidal model.

ABSTRACT: This study presents the first report on patterned nanowires (NWs) of dilute nitride GaAsSbN on p-Si (111) substrates by self-catalyzed plasma-assisted molecular beam epitaxy. Patterned NW array with GaAsSbN of Sb composition of 3% as a stem provided the best yield of vertical NWs. Large bandgap tuning of?~?75 meV, as ascertained from 4 K photoluminescence (PL), over a pitch length variation of 200-1200 nm has been demonstrated. Pitch-dependent axial and radial growth rates show a logistic sigmoidal growth trend different from those commonly observed in other patterned non-nitride III-V NWs. The sigmoidal fitting provides further insight into the PL spectral shift arising from differences in Sb and N incorporation from pitch induced variation in secondary fluxes. Results indicate that sigmoidal fitting can be a potent tool for designing patterned NW arrays of optimal pitch length for dilute nitrides and other highly mismatched alloys and heterostructures.

SUBMITTER: Johnson S

PROVIDER: S-EPMC7907112 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature

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Study of patterned GaAsSbN nanowires using sigmoidal model.

Johnson Sean S Pokharel Rabin R Lowe Michael M Kuchoor Hirandeep H Nalamati Surya S Davis Klinton K Rathnayake Hemali H Iyer Shanthi S

Scientific reports 20210225 1

This study presents the first report on patterned nanowires (NWs) of dilute nitride GaAsSbN on p-Si (111) substrates by self-catalyzed plasma-assisted molecular beam epitaxy. Patterned NW array with GaAsSbN of Sb composition of 3% as a stem provided the best yield of vertical NWs. Large bandgap tuning of ~ 75 meV, as ascertained from 4 K photoluminescence (PL), over a pitch length variation of 200-1200 nm has been demonstrated. Pitch-dependent axial and radial growth rates show a logistic sigmoi ...[more]

PMID: 33633245

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