MAGNETIC FIELD DETECTION DEVICE

摘要

A magnetic filed detection device is provided to detect a bio molecular material in a magnetic biosensor chip by limiting a stray filed in the device. A large magnetic resistance thin film is deposited on a substrate(1). A magnetic resistance device(20) with a circular ring structure is formed by performing an etching process. A metal thin film layer made of Au is deposited on the substrate and the magnetic resistance device. An electrode pad(24) is formed by a dry etching method or a lift up method using a negative light sensitive mask. An insulator thin film layer is deposited on the substrate, the magnetic resistance device, and the electrode pad. An insulator protective layer(28) is formed by removing the insulator thin film layer partially. A light sensitive magnetic bead thin film is deposited on the substrate, the electrode pad, and the insulator protective layer. A magnetic bead confining layer(32) is formed by removing the light sensitive magnetic bead thin film selectively.