用于低功耗微型磁通门的Co_(77)Fe_(2.5)Mn_(1.4)Mo_(2.1)Si_(13)B_4非晶薄膜研究

Study on the Co_(77)Fe_(2.5)Mn_(1.4)Mo_(2.1)Si_(13)B_4 amorphous films used for low power consumption micro-fluxgate

采用直流磁控溅射方法制备了一种适用于微型磁通门的Co77Fe2.5Mn1.4Mo2.1Si13B4非晶软磁铁芯薄膜,并对薄膜进行了200℃外加面内横向磁场的真空退火。利用振动样品磁强计(VSM)、X射线扫描仪(XRD)以及扫描电子显微镜(SEM)测试了薄膜的磁滞回线、相组成、表面形貌并进行了成分分析;使用制备得到的薄膜作为双铁芯磁通门的铁芯,测试了磁通门的激励电流、灵敏度和线性范围。结果表明,制备得到的薄膜主要呈非晶态,具有较大的相对磁导率并且磁滞回线在小磁场下出现明显的拐点;用作磁通门铁芯薄膜时,能得到类似使用Co基非晶带材铁芯时的明显的磁通门信号;工作在40kHz时,磁通门传感器能以有效值22mA的激励电流获得2700V/T的输出电压灵敏度。因此,制备得到的薄膜适用于低功耗、高灵敏度微型磁通门传感器。

Co77Fe2.5Mn1.4Mo2.1Si13B4 amorphous films which used for micro fluxgate were prepared by DC mag netron sputtering. Then the selected films were installed in a furnace and subsequently annealed in a vacuum chamber with an in plane transverse magnetic field. The magnetic hysteresis loop, phase composition, surface appearance, and elemental composition of the films were investigated through vibrating sample magnetometer, X-ray diffraction, and scanning electron microscopy. Using the prepared films as cores of a dual-core fluxgate, the excitation current, sensitivity, and linear ranges of the fluxgate were tested. The results showed that the amorphous phase was predominant with high conductivity and the hysteresis had obvious inflection point at a small magnetic field. When the films used as cores of fluxgate, obvious fluxgate signal similar with using Co- based amorphous ribbons was obtained. When working at 40kHz, the fluxgate exhibited high sensitivity of 2700V/T with a small excitation current of 22mA. Therefore, the film material was suitable for the application in the low power consumption and high sensitivity micro fluxgate.