Gao Sen, Hong Sanghyun, Park Soohyung, Jung Hyun Young, Liang Wentao, Lee Yonghee, Ahn Chi Won, Byun Ji Young, Seo Juyeon, Hahm Myung Gwan, Kim Hyehee, Kim Kiwoong, Yi Yeonjin, Wang Hailong, Upmanyu Moneesh, Lee Sung-Goo, Homma Yoshikazu, Terrones Humberto, Jung Yung Joon
Department of Mechanical and Industrial Engineering, Northeastern University, Boston, MA, USA.
Korea Institute of Science and Technology, Seoul, Republic of Korea.
Nat Commun. 2022 Jun 20;13(1):3467. doi: 10.1038/s41467-022-31174-x.
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.
对小型化和高性能设备的需求极大地推动了量子硅纳米线的发展。然而，制备大量具有有效量子限制尺寸的硅纳米线仍然具有挑战性。在此，我们通过开发一种无催化剂化学气相蚀刻工艺，制备出了长度/直径比大于10000的高密度垂直排列的亚5纳米硅纳米线。我们观察到，与传统硅相比，超窄硅纳米线内晶格异常减少高达20%，且在空气中具有良好的氧化稳定性。此外，该材料表现出4.16 eV的直接光学带隙和4.75 eV的准粒子带隙，激子结合能高达0.59 eV，表明存在显著的声子和电子限制。这些结果可能为研究高度受限的硅量子纳米结构的化学和物理性质提供契机，并探索它们在纳米电子学、光电子学和能源系统中的潜在应用。
