Using sugar as a mask material (SAAMM) in micro-nano fabrication: a high-performance, green and simple method

Abstract

Sugar is a natural food and a common organic compound that widely exists in nature. Sugar features easy patterning, solubility in water, environmental friendliness, low cost, and easy combination with micro-nano process. In this study, sugar is proposed to be used as a micro-nano mask material in micro-nano fabrication. Results show that sugar can be easily used to fabricate various kinds of micro-nano mask patterns on different wettability substrates. The fabrication method based on sugar mask has many advantages; it is diverse, simple, pollution-free, and inexpensive. Besides, sugar is strongly compatible with micro-nano fabrication technology, because it can maintain good peeling properties, good viscosity, and good stability in subsequent micro-nano fabrication and achieve the high-quality transfer of mask patterns. In addition, graphite super-lubricity micro-nano movable devices are made through the proposed sugar mask method, which also has good and reliable performance compared with e-beam lithography. Compared with micro-nano fabrication based on photoresist masks, micro-nano fabrication based on the sugar mask is simpler and cheaper. In the micro-nano processing of the sugar mask, the lift-off and removal of residual sugar can be easily completed using water. In summary, we believe that sugar as a mask material is effective and can be widely used in micro-nano manufacturing.

Novel Three-Dimensional and Biocompatible Lift-Off Method for Selective Metallization of a Scleral Contact Lens Electrode for Biopotential Detection

“…Areas of the three-dimensional substrate could be masked with gelling sugar and removed with water after the coating process without leaving any residue. This approach was inspired by the contributions of Byford et al, (36) and Zhang et al, (25). Whereas Zhang et al showed that two-dimensional lift-off is possible using maltose as a water-soluble masking material, Byford et al demonstrated that three-dimensional printing is capable of creating lift-off masks using commercial 3D printing filament.…”

“…These polymers, being tailored to the physiology of the eye, are highly sensitive to the organic solvents, and any contact with, for example, acetone, isopropanol, or ethanol would lead to the loss of the lens transparency. Instead of a photosensitive coating, alternative materials for sacrificial layers such as gelatin (21), agar-agar (21,22), shellac (23), paraffin wax (24), sugar (25,26), or even ice (27) are available. These are already widely used to manufacture different microstructures, for instance, brain implants (26) or various microfluidic systems (22,24,27).…”

“…There are several techniques for bioprinting, with the main applications being inkjet, extrusion, or laser-assisted printing (31). Compared to conventionally utilized materials in a liftoff process, sugar has positive aspects such as environmental friendliness and cost efficiency (25). Thus, a two-dimensional lift-off process was already carried out using maltose (25).…”

“…Compared to conventionally utilized materials in a liftoff process, sugar has positive aspects such as environmental friendliness and cost efficiency (25). Thus, a two-dimensional lift-off process was already carried out using maltose (25). Utilizing commercially available 3D printing filament and an extrusion 3D printer, it was additionally demonstrated that a lift-off process is possible on three-dimensional structures in order to produce, for instance, three-dimensional, selectively metallized high-frequency circuits (36).…”