Mechanical Approach to Nanomachining of Silicon Using Oxide Characteristics Based on Tribo Nanolithography (TNL) in KOH Solution

Abstract

The TNL (Tribo Nanolithography) method in aqueous solution uses the atomic force microscopy as a machining tool for the nanoscale fabrication of silicon. A specially designed cantilever with a diamond tip allows the formation of oxide patterns easily by a simple scratching process. A rectangular structure with a slope can be fabricated by a process in which a thin oxide layer rapidly forms in the substrate at the diamond-tip sample junction along the scanning path of the tip, and, simultaneously, the area uncovered with the oxide layer is being etched. Etching in KOH and HF is conducted to verify corrosion characteristics of oxide.

Characteristics of mask layer on (100) silicon induced by tribo-nanolithography with diamond tip cantilevers based on AFM

“…However, TNL-induced oxide pattern is not always excellent etch mask because the selectivity may change according to the amorphous state or geometrical state, which depends on the various experimental conditions. From our experiments, it can be known that the amorphous layer induced by TNL process has the etch characteristics similar to the SiO 2 , which withstands against KOH solution where dissolves in HF solution [8]. From those results, it can be clearly known that the amorphous layer was completely removed and has no further etch resistance against KOH solution after dipping in HF for 20 min.…”

“…Recently, we reported a new nanofabrication technique, TNL (tribo-nanolithography), which consists of sequential processes, nano-scratching and wet chemical etching [7,8]. The simple scratching can form an amorphous layer on the silicon substrate, which acting as an etching mask.…”

Nanoscale fabrication in aqueous KOH solution using tribo-nanolithography

“…From our previous study, we know that the thickness of the amorphous layer formed by the TNL method is proportional to the normal load. 10 Hence, this result indicates that a hard amorphous layer is formed at any normal load, and it has enough corrosion resistance for 5 mass % KOH solution without having any influence on the inclination of the structure.…”

Three-Dimensional Lithography Using Combination of Nanoscale Processing and Wet Chemical Etching

“…Additionally, threedimensional structures can be fabricated by controlling the etching mask. Herein we describe a method of three-dimensional fabrication using TNL [19,[22][23][24][25][26][27][28] with wet chemical etching.…”