Abstract
We have successfully fabricated a thin-film flux-gate magnetic sensor (TFG sensor) on a 2.6mm square chip utilizing photofabrication technique, and a compact hybrid-integrated-circuit (HIC) driver for this TFG sensor. The sensor consists of a permalloy ring core, an excitation coil, and a differential pickup coil. The TFG sensor and the driver have been downsized, in order to expand their field of applications. We have also developed a "bi-axis TFG", which has two sensing axes meeting at right angle with each other and which is yet of the same size as the conventional "mono-axis TFG". The resolution for magnetic flux density of the TFG sensor is below 50nT, and the magnetic sensitivities of the mono-axis TFG and bi-axis TFG are 30mV/μT and 39mV/μT respectively. Excellent output linearity (0.2%f.s.) is ensured for magnetic flux density in the range from -100μT to 100μT.
