We report a non-lithographical method for the fabrication of ultra-thin silicon (Si) nanowire (NW) and nano-sheet arrays through metal-assisted- chemical-etching (MacEtch) with gold (Au). The mask used for metal patterning is a vertical InAs NW array grown on a Si substrate via catalyst-free, strain-induced, one-dimensional heteroepitaxy. Depending on the Au evaporation angle, the shape and size of the InAs NWs are transferred to Si by Au-MacEtch as is (NWs) or in its projection (nano-sheets). The Si NWs formed have diameters in the range of 25-95nm, and aspect ratios as high as 250 in only 5min etch time. The formation process is entirely free of organic chemicals, ensuring pristine Au-Si interfaces, which is one of the most critical requirements for high yield and reproducible MacEtch.
ASJC Scopus subject areas
- Materials Science(all)
- Mechanics of Materials
- Mechanical Engineering
- Electrical and Electronic Engineering