Design and Analysis of Microcantilever based Biosensor for Detection of Human Immunodeficiency Virus

This paper presents the effect of a microcantilever beam biosensor size on deflection using SU8 material. This design is optimized for detecting Human Immunodeficiency Virus (HIV) molecules in the human body. The microcantilever is designed as a thin beam, it consists SU8 square diaphragm anchored by four SU8 cantilevers, so to find the optimal microcantilever geometry, the cantilever’s length and width are varied, in the range of length 200-400 μm, width 75-175 μm, and thickness is set at 3 μm. Meanwhile, the diaphragm size was set at 505 μm × 505 μm × 3 μm. This MEMS-based cantilever beam design was designed using COMSOL Multiphysics software. The geometric dimensions with the best deflection that can be used in microcantilever biosensor applications are when the length is 400 µm, the width is 75 µm, and the thickness is 3 µm, which give a displacement of 3.08 × 10 ^-11 μm. Meanwhile, the relationship between the microcantilever size and the displacement is directly proportional, as the number of bound particles increases, the displacement also increases, and short and narrow cantilevers show higher displacement.