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  • Facile Process for Fabrication of Silicon Micro–Nanostructures of Different Shapes as Molds for Fabricating Flexible Micro–Nanostructures and Wearable Sensors
Title: Facile Process for Fabrication of Silicon Micro–Nanostructures of Different Shapes as Molds for Fabricating Flexible Micro–Nanostructures and Wearable Sensors
We report a method to fabricate silicon micro–nanostructures of different shapes by tuning the number of layers and the sizes of self-assembled polystyrene beads, which serve as the mask, and by tuning the reactive ion etching (RIE) time. This process is simple, scalable, and inexpensive without using any sophisticated nanomanufacturing equipment. Specifically, in this work, we demonstrate the proposed process by fabricating silicon micro- or nanoflowers, micro- or nanobells, nanopyramids, and nanotriangles using a self-assembled monolayer or bilayer of polystyrene beads as the mask. We also fabricate flexible micro–nanostructures by using silicon molds with micro–nanostructures. Finally, we demonstrate the fabrication of bandage-type electrochemical sensors with micro–nanostructured working electrodes for detecting dopamine, a neurotransmitter related to stress and neurodegenerative diseases in artificial sweat. All these demonstrations indicate that the proposed process provides a low-cost, easy-to-use approach for fabricating silicon micro–nanostructures and flexible micro–nanostructures, thus paving a way for developing wearable micro–nanostructures enabled sensors for a variety of applications in an efficient manner.  more » « less
Award ID(s):
2031826
PAR ID:
10470199
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
American Chemical Society
Date Published:
Journal Name:
ACS Applied Materials & Interfaces
Volume:
15
Issue:
9
ISSN:
1944-8244
Page Range / eLocation ID:
12202 to 12208
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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