Anisotropic Dry Etching ( RIE ) for Micro and Nanogap Fabrication

The main objective of this research is to develop a micro and nanogap structure using dry anisotropic etching –Reactive Ion EtchingRIE. Amorphous silicon material is used in the micro and nanogap structure and gold as electrode. The fabrication processes of the micro and nanostructure are based on conventional photolithography, wet etching for the Al pattern and wet etching for a-Si pattern using RIE process. Reactive ion etching (IP-RIE) has been applied and developed as essential method for etching micro and nanogap semiconductors. The fabrication and preparation methods to fabricate micro and nanogaps using RIE properties are discussed along with their advantages towards the nanotechnology and biodetection. In this research, 2 masks designs are proposed. First mask is the lateral micro and nanogap and the second mask is for gold pad electrode pattern. Lateral micro and nanogaps are introduced in the fabrication process using amorphous silicon and gold as an electrode. As a result we need to deposit Al layer over the amorphous silicon semiconductor material before coating a photoresist to protect the a-Si layer during the etching and using the Al layer as a hard mask. The requirement time to etch 1μm amorphous silicon pattern completely by using IPRIE to fabricate the micro and nanogap structure its take approximately 30sec. These results are better than those using wet anisotropic etching