Room Temperature Growth of Silica Nanowires on Top of Ultrathin Si Nanowires Synthesized with Sn‐Cu Bimetallic Seeds

Si nanowires (NWs) are grown by the vapor–liquid–solid method using Cu–Sn bimetallic catalysts in a plasma-enhanced chemical vapor deposition (PECVD) reactor. The microstructure of NWs is analyzed transmission electron microscopy and energy-dispersive X-ray spectroscopy. An amorphous SiO2 region, much larger than native oxide, present on top each crystalline SiNW: SiNWs with diameter below 10 nm, it takes form silica NW up to 50 nm length. new separates initial catalyst particle into one that stays contact SiNW or more lies at NW. former made Cu Cu3Si contains no Sn, whereas latter keeps amounts both elements. observed appears be result mechanism oxidation catalyzed Cu3Si. deposit after growth, PECVD reactor, protecting 2 thick layer hydrogenated Si, completely suppresses this mechanism. Reference for future applications based Cu–Sn-catalyzed quantum-sized provided.