High Sensitivity Biomolecular Recognition Device Based on Giant Magnetoresistance Effect

摘要

The structure and microfabrication, the detecting theory and the way of biomolecular recognition device based on giant magnetoresistance (GMR) effect are introduced, also the signal detecting and processing instrumentation are presented. Here the GMR biosensor was fabricated with magnetic tunnel junction (MJT) material. The biomolecular recognition device contains an array of MJT sensors, single MJT sensor size is 10 μm×20 μm, tunneling magnetoresistance ratio (TMR) at room temperature is 52.2%, the typical values of junction resistance-area product Rs is 2.6 kΩμm{sup}2, detecting sensitivity of this system is about 8×10{sup}(-4) A·m{sup}(-1). Bioadaptation layer of this device was fabricated with PDMS the thickness of which is less than 100 nm.