Microstructure pattern etching by reactive ion etching (RIE) for future reproductivity of nanogap biosensor

This article is a study about reactive ion etching as applied to etch substrate directionality, which is the important feature of RIE. The biosensors based on polysilicon material should be sensitive and selective for the detection of bio molecule. The objective of this research is to design, and fabricate polysilicon microstructures. The proposed microstructures were designed initially by using AutoCAD software and then transferred to commercial chrome mask. Standard photolithography process coupled with reactive ion etching (RIE) was used for fabrication of proposed microstructures. The fabrication process start by microstructures formation on resist and then by reactive ion etching (RIE) the proposed polysilicon microstructures was created onto sample wafer. Future work will focuse on to reduce the microstructures size by thermal oxidation process until the structures break at junction and create gaps of nano sizes. For biomolecules sensing applications, the sizes of the gaps must be small enough to allow the biomolecule inserted into the gaps space to connect both leads to keep the molecules in a relaxed and undistorted state.