SCS Nano-Structures Fabricated by Hybrid process of HNA selective etching and oxidization

In this paper, we developed a hybrid process of fabricating single crystal silicon nanostructures by HNA selective etching followed by an oxidization with a common photolithography. HNA etch heavy and light doped silicon with the etching selectivity about 160:1. On the other hand, silicon will be consumed by an oxidization process. Based on these characteristics, we first fabricate some bigger structures with an optical lithography, and then processed the structures with heavy doping, diffusion, HNA etching, oxidization and BHF etching. At last, silicon nano-structures with the line width of ~50nm were successfully fabricated. The results are almost catches up with the electron beam lithography, but with much low cost, time saving and reliability. The line width fabricated with this method can be further decreased by a precise controlling of the process parameters, include doping energy and concentration, annealing and oxidization time.