Sub-100 nm Si nanowire and nano-sheet array formation by MacEtch using a non-lithographic InAs nanowire mask.
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 ∼25-95 nm, and aspect ratios as high as 250 in only 5 min 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.
Department of Electrical and Computer Engineering, Micro and Nanotechnology Laboratory, Materials Research Laboratory, University of Illinois, Urbana, IL 61801, USA.
Jae Cheol
JC
Shin
Chen
C
Zhang
Xiuling
X
Li