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

Sen Gao; Sanghyun Hong; Soohyung Park; Hyun Young Jung; Wentao Liang; Yonghee Lee; Chi Won Ahn; Ji Young Byun; Juyeon Seo; Myung Gwan Hahm; Hyehee Kim; Kiwoong Kim; Yeonjin Yi; Hailong Wang; Moneesh Upmanyu; Sung-Goo Lee; Yoshikazu Homma; Humberto Terrones; Yung Joon Jung

doi:10.1038/s41467-022-31174-x

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

Nat Commun. 2022 Jun 20;13(1):3467. doi: 10.1038/s41467-022-31174-x.

Authors

Sen Gao^#¹, Sanghyun Hong^#¹, Soohyung Park², Hyun Young Jung³, Wentao Liang⁴, Yonghee Lee⁵, Chi Won Ahn⁵, Ji Young Byun², Juyeon Seo¹, Myung Gwan Hahm⁶, Hyehee Kim¹, Kiwoong Kim⁷, Yeonjin Yi⁷, Hailong Wang⁸, Moneesh Upmanyu¹, Sung-Goo Lee⁹, Yoshikazu Homma¹⁰, Humberto Terrones¹¹, Yung Joon Jung^{12

13}

Affiliations

¹ Department of Mechanical and Industrial Engineering, Northeastern University, Boston, MA, USA.
² Korea Institute of Science and Technology, Seoul, Republic of Korea.
³ Department of Energy Engineering, Gyeongsang National University, Jinju, Republic of Korea.
⁴ Kostas Advanced Nano-Characterization Facility, Kostas Research Institute, Northeastern University, Burlington, MA, USA.
⁵ National Nano Fab Center, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea.
⁶ Department of Materials Science and Engineering, Inha University, Incheon, Republic of Korea.
⁷ Institute of Physics and Applied Physics, Yonsei University, Seoul, Republic of Korea.
⁸ CAS Key Laboratory of Mechanical Behavior and Design of Materials, Department of Modern Mechanics, University of Science and Technology of China, Hefei, China.
⁹ Advanced Materials Division, Korea Research Institute of Chemical Technology, Daejeon, Republic of Korea.
¹⁰ Department of Physics, Tokyo University of Science, Tokyo, Japan.
¹¹ Department of Physics, Applied Physics and Astronomy, Rensselaer Polytechnic Institute, Troy, NY, USA.
¹² Department of Mechanical and Industrial Engineering, Northeastern University, Boston, MA, USA. y.jung@northeastern.edu.
¹³ Kostas Advanced Nano-Characterization Facility, Kostas Research Institute, Northeastern University, Burlington, MA, USA. y.jung@northeastern.edu.

^# Contributed equally.

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.

Abstract

Grants and funding