Greyscale lithography-based fabrication of thin polymeric cantilevers for MEMS/NEMS applications

Abstract

Highly photosensitive epoxy-based polymer SU8 is becoming extensively used for MicroElectro-Mechanical Systems (MEMS) and microfluidic devices not only as a negative photoresist but also as the basic constitutional material because of the easy fabrication of devices with tailored dimensions from µm to mm sizes. Here, we have shown a one-step process for the fabrication of thin cantilever arrays of thickness upto 1-2 µm using MASKLESS GRAYSCALE LITHOGRAPHY (MGL). Microfabricated polymeric disposable cantilevers can be utilized for label-free biochemical sensing with desirable advantages such as high sensitivity due to low Young’s modulus, low cost compared to its Silicon counterpart and ease in reproducible fabrication. Microcantilever arrays of different shapes were fabricated reproducibly by optimizing the process parameters. Arrays of suspended cantilevers can be used for the fabrication of chemical/biochemical sensors as SU-8 is highly resistant to chemicals and biocompatible making it a suitable material for such sensors.