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Catalyst-free synthesis of sub-5 nm silicon nanowire arrays with massive lattice contraction and wide bandgap.

ABSTRACT: The need for miniaturized and high-performance devices has attracted enormous attention to the development of quantum silicon nanowires. However, the preparation of abundant quantities of silicon nanowires with the effective quantum-confined dimension remains challenging. Here, we prepare highly dense and vertically aligned sub-5 nm silicon nanowires with length/diameter aspect ratios greater than 10,000 by developing a catalyst-free chemical vapor etching process. We observe an unusual lattice reduction of up to 20% within ultra-narrow silicon nanowires and good oxidation stability in air compared to conventional silicon. Moreover, the material exhibits a direct optical bandgap of 4.16 eV and quasi-particle bandgap of 4.75 eV with the large exciton binding energy of 0.59 eV, indicating the significant phonon and electronic confinement. The results may provide an opportunity to investigate the chemistry and physics of highly confined silicon quantum nanostructures and may explore their potential uses in nanoelectronics, optoelectronics, and energy systems.

SUBMITTER: Gao S

PROVIDER: S-EPMC9209539 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature

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Catalyst-free synthesis of sub-5 nm silicon nanowire arrays with massive lattice contraction and wide bandgap.

Gao Sen S Hong Sanghyun S Park Soohyung S Jung Hyun Young HY Liang Wentao W Lee Yonghee Y Ahn Chi Won CW Byun Ji Young JY Seo Juyeon J Hahm Myung Gwan MG Kim Hyehee H Kim Kiwoong K Yi Yeonjin Y Wang Hailong H Upmanyu Moneesh M Lee Sung-Goo SG Homma Yoshikazu Y Terrones Humberto H Jung Yung Joon YJ

Nature communications 20220620 1

The need for miniaturized and high-performance devices has attracted enormous attention to the development of quantum silicon nanowires. However, the preparation of abundant quantities of silicon nanowires with the effective quantum-confined dimension remains challenging. Here, we prepare highly dense and vertically aligned sub-5 nm silicon nanowires with length/diameter aspect ratios greater than 10,000 by developing a catalyst-free chemical vapor etching process. We observe an unusual lattice ...[more]

PMID: 35725850

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Dataset Information

Catalyst-free synthesis of sub-5 nm silicon nanowire arrays with massive lattice contraction and wide bandgap.

Publications

Catalyst-free synthesis of sub-5 nm silicon nanowire arrays with massive lattice contraction and wide bandgap.

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